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a LANGE medical book

CURRENTDiagnosis & Treatment

Critical CareT H I R D E D I T I O N

Edited by

Frederic S. Bongard, MDProfessor of Surgery

David Geffen School of MedicineUniversity of California, Los Angeles

Chief, Division of Trauma and Critical CareDirector of Surgical EducationHarbor-UCLA Medical Center

Torrance, California

Darryl Y. Sue, MDProfessor of Clinical Medicine


Director, Medical-Respiratory Intensive Care UnitDivision of Respiratory and Critical Care Physiology and Medicine

Associate Chair and Program DirectorDepartment of Medicine

Harbor-UCLA Medical CenterTorrance, California

Janine R. E. Vintch, MDAssociate Clinical Professor of Medicine


Divisions of General Internal Medicine and Respiratory and Critical Care Physiology and MedicineHarbor-UCLA Medical Center

Torrance, California

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http://dx.doi.org/10.1036/007143657X

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iii

ContentsAuthors viiPreface xi

1. Philosophy & Principles of Critical Care 1

Darryl Y. Sue, MD, & Frederic S. Bongard, MD

General Principles of Critical Care 1Role of the Medical Director of the Intensive

Care Unit 8Critical Care Scoring 10Current Controversies &

Unresolved Issues 12

2. Fluids, Electrolytes, & Acid-Base 14

Darryl Y. Sue, MD, & Frederic S. Bongard, MD

Disorders of Fluid Volume 14Disorders of Water Balance 22Disorders of Potassium Balance 34Disorders of Phosphorus Balance 42Disorders of Magnesium Balance 47Disorders of Calcium Balance 51Acid-Base Homeostasis & Disorders 56

3. Transfusion Therapy 71

Elizabeth D. Simmons, MD

Blood Components 71Blood Component Administration 79Complications of Transfusion 79Current Controversies &

Unresolved Issues 82

4. Pharmacotherapy 88

Darryl Y. Sue, MD

Pharmacokinetic Parameters 88Pharmacokinetic Considerations 88Medication Errors & Prevention in

the ICU 95

5. Intensive Care Anesthesia & Analgesia 97

Tai-Shion Lee, MD, & Biing-Jaw Chen, MD

Physiologic Effects of Anesthesia inthe Critically Ill 97

Airway Management 101Pain Management in the ICU 103Muscle Relaxants in Intensive Care 106Sedative-Hypnotics for the

Critically Ill 110Malignant Hyperthermia 115

6. Nutrition 117

John A. Tayek, MD

Nutrition & Malnutrition in the Critically IllPatient 117

Nutritional Therapy 126Nutritional Support in Specific Diseases 130New Treatment Strategies for the Malnourished

Critically Ill Patient 134

7. Imaging Procedures 137

Kathleen Brown, MD, Steven S. Raman, MD,& Nam C. Yu, MD

Imaging Techniques 137Iodinated Contrast Agents 138Use of Central Venous Catheters for Contrast

Injection 139Imaging of Support & Monitoring Devices

in the ICU 139Imaging in Pulmonary Diseases 144Imaging in Pleural Disorders 161Imaging of the Abdomen & Pelvis 167Imaging of Acute Gallbladder & Biliary

Tract Disorders 181Imaging in Emergent & Urgent Genitourinary

Conditions 184

8. Intensive Care Monitoring 187

Kenneth Waxman, MD, Frederic S. Bongard, MD,& Darryl Y. Sue, MD

Electrocardiography 187Blood Pressure Monitoring 188Central Venous Catheters 193Pulmonary Artery Catheterization 196Cardiac Output 199Pulse Oximetry 201Airway CO2 Monitoring 203Transcutaneous Blood Gases 204Respiratory Mechanics 204Respired Gas Analysis 206Clinical Applications 206

9. Transport 208

Samuel J. Stratton, MD, MPH

Interhospital Transport 208Equipment & Monitoring 211Education & Training 212Reimbursement Standards & Costs 213Current Controversies & Unresolved Issues 214

For more information about this title, click here

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� CONTENTSiv

10. Ethical, Legal, & Palliative/End-of-LifeCare Considerations 215

Paul A. Selecky, MD

Ethical Principles 215Conflicts Between Ethical Principles 216Ethical Decision Making 216Advance Care Planning 217Medicolegal Aspects of Decision Making 217Withholding & Withdrawing Life Support 218Organ Donation 219Role of the Health Care Professional 219Web Sites for Health Care Ethics Information

& Policies 221

11. Shock & Resuscitation 222

Frederic S. Bongard, MD

Hypovolemic Shock 222Distributive Shock 230Cardiac Shock 242

12. Respiratory Failure 247

Darryl Y. Sue, MD, & Janine R. E. Vintch, MD

Pathophysiology of Respiratory Failure 247Treatment of Acute Respiratory Failure 253Acute Respiratory Failure

from Specific Disorders 280

13. Renal Failure 314

Andre A. Kaplan, MD

Nondialytic Therapy for Acute Renal Failure 330Dialytic Therapy for the Critically Ill Patient 334Critical Illness in Patients with Chronic

Renal Failure 342

14. Gastrointestinal Failure in the ICU 345

Gideon P. Naudé, MD

Pancreatitis 345Bowel Obstruction 351Obstruction of the Large Bowel 354Adynamic (Paralytic) Ileus 355Diarrhea & Malabsorption 356Pancreatic Insufficiency 357Lactase Deficiency 357Diarrhea 357

15. Infections in the Critically Ill 359

Laurie Anne Chu, MD, & Mallory D. Witt, MD

Sepsis 359Community-Acquired Pneumonia 362Urosepsis 365Infective Endocarditis 367

Necrotizing Soft Tissue Infections 370Intraabdominal Infections 372Infections in Special Hosts 373Principles of Antibiotic Use in the ICU 376Evaluation of the ICU Patient with New Fever 379Nosocomial Pneumonia 379Urinary Catheter–Associated Infections 382Intravenous Catheter–Associated Infections 384Clostridium Difficile–Associated Diarrhea 386Hematogenously Disseminated Candidiasis 388Antimicrobial Resistance in the ICU 389Botulism 392Tetanus 394

16. Surgical Infections 397

Timothy L. Van Natta, MD

Evaluation and Management of Infection byBody Site 400

17. Bleeding & Hemostasis 409


Approach to the Bleeding Patient 427Current Controversies & Unresolved Issues 427

18. Psychiatric Problems 431

Stuart J. Eisendrath, MD,& John R. Chamberlain, MD

Delirium 431Depression 436Anxiety & Fear 438Staff Issues 440

19. Care of the Elderly Patient 443

Shawkat Dhanani, MD, MPH,& Dean C. Norman, MD

Physiologic Changes with Age 443Management of the Elderly Patient in the ICU 445Special Considerations 447

20. Critical Care of the Oncology Patient 451

Darrell W. Harrington, MD, & Darryl Y. Sue, MD

Central Nervous System Disorders 451Metabolic Disorders 457Superior Vena Cava Syndrome 465

21. Cardiac Problems in Critical Care 467

Shelley Shapiro, MD, PhD,& Malcolm M. Bersohn, MD, PhD

Atrial Arrhythmias 486Ventricular Arrhythmias 488

�CONTENTS v

Heart Block 491Cardiac Problems During Pregnancy 493Toxic Effects of Cardiac Drugs 494

22. Coronary Heart Disease 498

Kenneth A. Narahara, MD

Physiologic Considerations 498Myocardial Ischemia (Angina Pectoris) 499Acute Coronary Syndromes: Unstable Angina

and Non-ST-Segment-ElevationMyocardial Infarction 502

Acute Myocardial Infarction withST-Segment Elevation 505

23. Cardiothoracic Surgery 514

Edward D. Verrier, MD, & Craig R. Hampton, MD

Aneurysms, Dissections, & Transectionsof the Great Vessels 514

Postoperative Arrhythmias 518Bleeding, Coagulopathy, & Blood Product

Utilization 520Cardiopulmonary Bypass, Hypothermia,

Circulatory Arrest, & VentricularAssistance 525

Postoperative Low-Output States 529

24. Pulmonary Disease 534

Darryl Y. Sue, MD, & Janine R. E. Vintch, MD

Status Asthmaticus 534Life-Threatening Hemoptysis 540Deep Venous Thrombosis & Pulmonary

Thromboembolism 545Anaphylaxis 562Angioedema 563

25. Endocrine Problems in theCritically Ill Patient 566

Shalender Bhasin, MD, Piya Ballani, MD, & Ricky Phong Mac, MD

Thyroid Storm 566Myxedema Coma 570Acute Adrenal Insufficiency 572Sick Euthyroid Syndrome 576

26. Diabetes Mellitus, Hyperglycemia,& the Critically Ill Patient 581

Eli Ipp, MD, & Chuck Huang, MD

Diabetic Ketoacidosis 581Hyperglycemic Hyperosmolar

Nonketotic Coma 593Management of the Acutely Ill Patient

with Hyperglycemia or Diabetes Mellitus 594

Hyperglycemia 594Hypoglycemia 595Other Complications of

Diabetes Mellitus 597

27. HIV Infection in the Critically IllPatient 598

Mallory D. Witt, MD, & Darryl Y. Sue, MD

Complications of HIV Disease:An Overview 598

Other Infectious Causes of Pneumonia andRespiratory Failure 604

28. Dermatologic Problemsin the Intensive Care Unit 609

Kory J. Zipperstein, MD

Common Skin Disorders 609Drug Reactions 612Purpura 619Life-Threatening Dermatoses 623Cutaneous Manifestations of Infection 626

29. Critical Care of Vascular Disease& Emergencies 632

James T. Lee, MD, & Frederic S. Bongard, MD

Vascular Emergencies in the ICU 632Critical Care of the Vascular

Surgery Patient 651

30. Critical Care of Neurologic Disease 658

Hugh B. McIntyre, MD, PhD, Linda Chang, MD,& Bruce L. Miller, MD

Encephalopathy & Coma 658Seizures 662Neuromuscular Disorders 666Cerebrovascular Diseases 673

31. Neurosurgical Critical Care 680

Duncan Q. McBride, MD

Head Injuries 680Aneurysmal Subarachnoid Hemorrhage 686Tumors of the Central Nervous System 688Cervical Spinal Cord Injuries 690

32. Acute Abdomen 696

Allen P. Kong, MD, & Michael J. Stamos, MD

Specific Pathologic Entities 700Current Controversies & Unresolved Issues 701

� CONTENTSvi

33. Gastrointestinal Bleeding 703

Sofiya Reicher, MD, & Viktor Eysselein, MD

Upper Gastrointestinal Bleeding 703Lower Gastrointestinal Bleeding 710

34. Hepatobiliary Disease 714

Hernan I. Vargas, MD

Acute Hepatic Failure 714Acute Gastrointestinal Bleeding from

Portal Hypertension 716Ascites 717Hepatorenal Syndrome 719Preoperative Assessment & Perioperative

Management of Patients with Cirrhosis 720Liver Resection in Patients with Cirrhosis 720

35. Burns 723

David W. Mozingo, MD, William G. Cioffi, Jr., MD,& Basil A. Pruitt, Jr., MD

I. Thermal Burn Injury 723Initial Care of the Burn Patient 727Principles of Burn Treatment 730Care of the Burn Wound 735Postresuscitation Period 741Nutrition 743II. Chemical Burn Injury 749III. Electrical Burn Injury 750

36. Poisonings & Ingestions 752

Diane Birnbaumer, MD

Evaluation of Poisoning in the Acute CareSetting or ICU 752

Treatment of Poisoning in the ICU 754Management of Specific Poisonings 757

37. Care of Patients withEnvironmental Injuries 786

James R. Macho, MD, & William P. Schecter, MD

Heat Stroke 786Hypothermia 788Frostbite 791Near-Drowning 793Envenomation 795Electric Shock & Lightning Injury 798Radiation Injury 800

38. Critical Care Issues in Pregnancy 802

Marie H. Beall, MD, & Andrea T. Jelks, MD

Physiologic Adaptation to Pregnancy 802General Considerations in the Care of the

Pregnant Patient in the ICU 804Management of Critical Complications

of Pregnancy 807

39. Antithrombotic Therapy 821


Physical Measures 821Antiplatelet Agents 821Anticoagulants 825New Anticoagulants 831Defibrinating Agents 832Oral Anticoagulants 832Thrombolytic Therapy 836Antithrombotic Therapy in Pregnancy 838Antiphospholipid Antibody Syndrome 839Thrombosis in Cancer Patients 840Future Directions 840

Index 843

vii

AuthorsPiya Ballani, MDSouthern California Endocrine Medical Group, Anaheim,

[email protected] Problems in the Critically Ill Patient

Marie H. Beall, MDClinical Professor of Obstetrics and Gynecology, David

Geffen School of Medicine, University of California,Los Angeles; Vice Chair, Department of Obstetrics andGynecology, Harbor-UCLA Medical Center, Torrance,California

[email protected] Care Issues in Pregnancy

Malcolm M. Bersohn, MD, PhDProfessor of Medicine, David Geffen School of Medicine,

University of California, Los Angeles; Director,Arrhythmia Service, Veterans Administration GreaterLos Angeles Health Care System, Los Angeles, California

[email protected] Problems in Critical Care

Shalender Bhasin, MDProfessor of Medicine, Boston University School of

Medicine; Chief, Section of Endocrinology, Diabetes, andNutrion, Boston Medical Center, Boston, Massachusetts

[email protected] Problems in the Critically Ill Patient

Diane Birnbaumer, MD, FACEPProfessor of Clinical Medicine, David Geffen School of

Medicine, University of California, Los Angeles; AssociateResidency Program Director, Harbor-UCLA MedicalCenter, Torrance, California

[email protected] & Ingestions

Frederic S. Bongard, MDProfessor of Surgery, David Geffen School of Medicine,

University of California, Los Angeles; Chief, Division ofTrauma and Critical Care, Director of SurgicalEducation, Harbor-UCLA Medical Center, Torrance,California

[email protected] & Principles of Critical Care; Fluids, Electrolytes,

& Acid-Base; Intensive Care Monitoring; Shock &Resuscitation; Critical Care of Vascular Disease &Emergencies

Kathleen Brown, MDProfessor of Clinical Radiology, David Geffen School

of Medicine, University of California,Los Angeles, California

[email protected] Procedures

John R. Chamberlain, MDAssistant Clinical Professor, Department of Psychiatry,

University of California, San Francisco; AssistantDirector, Psychiatry and the Law Program, Universityof California, San Francisco, San Francisco, California

[email protected] Problems

Linda Chang, MDProfessor of Medicine, John A. Burns School of Medicine,

University of Hawaii; Queens Medical Center, Honolulu,Hawaii

[email protected] Care of Neurologic Disease

Biing-Jaw Chen, MDClinical Associate Professor, David Geffen School of

Medicine, University of California, Los Angeles,Harbor-UCLA Medical Center, Torrance, California

[email protected] Care Anesthesia & Analgesia

Laurie Anne Chu, MDSouthern California Permanente Medical Group, Kaiser

Bellflower Medical Center, Bellflower, [email protected] in the Critically Ill

William G. Cioffi, Jr., MDJ. Murray Beardsley Professor & Chairman, Department

of Surgery, Brown Medical School; Surgeon-in-Chief,Department of Surgery, Rhode Island Hospital,Providence, Rhode Island

[email protected]

Shawkat Dhanani, MD, MPHAssociate Clinical Professor, David Geffen School of

Medicine, University of California, Los Angeles; Director,Geriatric Evaluation and Management Unit, VeteransAdministration Greater Los Angeles Healthcare System,Los Angeles, California

[email protected] of the Elderly Patient

Copyright © 2008 by The McGraw-Hill Companies, Inc. Click here for terms of use.

� AUTHORSviii

Stuart J. Eisendrath, MDProfessor of Clinical Psychiatry, Department of Psychiatry,

University of California, San Francisco; Director ofClinical Services, Langley Porter Psychiatric Hospitaland Clinics, San Francisco, California

[email protected] Problems

Viktor Eysselein, MDProfessor of Medicine, David Geffen School of Medicine,

University of California, Los Angeles; Clinical Professorof Medicine, Harbor-UCLA Medical Center, Torrance,California

[email protected] Bleeding

Craig R. Hampton, MDStaff Surgeon, St. Luke’s Cardiothoracic Surgical Associates,

St. Luke's Hospital, Duluth, [email protected] Surgery

Darrell W. Harrington, MDChief, Division of General Internal Medicine,

Harbor-UCLA Medical Center, Torrance, [email protected] Care of the Oncology Patient

Chuck Huang, MDPrivate Practice, Internal Medicine and Endocrinology,

Grants Pass, OregonDiabetes Mellitus, Hyperglycemia, & the Critically Ill Patient

Eli Ipp, MDProfessor, David Geffen School of Medicine, University

of California, Los Angeles; Head, Section of Diabetesand Metabolism, Harbor-UCLA Medical Center,Torrance, California

[email protected] Mellitus & the Critically Ill Patient

Andrea T. Jelks, MDAssociate Clinical Professor, Stanford University Medical

Center; Maternal Fetal Medicine Specialist, Santa ClaraValley Medical Center, San Jose, California

[email protected] Care Issues in Pregnancy

Andre A. Kaplan, MDProfessor of Medicine, University of Connecticut Health

Center; Chief, Blood Purification, John DempseyHospital, Farmington, Connecticut

[email protected] Failure

Allen P. Kong, MDResident Physician, Department of Surgery,

University of California, Irvine, Orange, [email protected] Abdomen

James T. Lee, MDFellow, Peripheral Vascular and Endovascular Surgery,

Division of Vascular Surgery, Harbor-UCLA MedicalCenter, Torrance, California

[email protected] Care of Vascular Disease & Emergencies

Tai-Shion Lee, MDClinical Professor, David Geffen School of Medicine,

University of California, Los Angeles, Harbor-UCLAMedical Center, Torrance, California

[email protected] Care Anesthesia & Analgesia

Ricky Phong Mac, MDClinical Endcrinology Fellow, Division of Endocrinology,

Metabolism and Molecular Medicine, Charles R. DrewUniversity of Medicine and Science, Los Angeles,California

Endocrine Problems in the Critically Ill Patient

James R. Macho, MD, FACSEmeritus Professor of Surgery, University of California, San

Francisco; Director, Bothin Burn Center and Chief ofCritical Care Medicine, Saint Francis Memorial Hospital,San Francisco, California

[email protected] of Patients with Environmental Injuries

Duncan Q. McBride, MDAssociate Professor of Clinical Neurosurgery, Department

of Neurosurgery, David Geffen School of Medicine,University of California, Los Angeles; Chief, Division ofNeurosurgery, Harbor-UCLA Medical Center, Torrance,California

[email protected] Critical Care

Hugh B. McIntyre, MDProfessor of Neurology, David Geffen School of Medicine,

University of California, Los Angeles, Harbor-UCLAMedical Center, Torrance, California


�AUTHORS ix

Bruce L. Miller, MDClausen Distinguished Professor of Neurology, University

of California, San Francisco; Memory and Aging Center,San Francisco, California


David W. Mozingo, MDProfessor of Surgery and Anesthesiology, University of

Florida; Chief, Division of Acute Care Surgery, Director,Shands Burn Center, Gainesville, Florida

[email protected]

Kenneth A. Narahara, MDProfessor of Medicine, David Geffen School of Medicine,

University of California, Los Angeles, School ofMedicine; Assistant Chair for Clinical Affairs,Department of Medicine, Director, Coronary Care,Division of Cardiology, Harbor-UCLA Medical Center,Torrance, California

[email protected] Heart Disease

Gideon P. Naudé, MDChairman, Department of Surgery, Tuolumne General

Hospital, Sonora, [email protected] Failure in the ICU

Dean C. Norman, MDChief of Staff, Veterans Administration Greater Los Angeles

Healthcare System; Professor of Medicine, University ofSouthern California, Los Angeles, California

[email protected] of the Elderly Patient

Basil A. Pruitt, Jr., MD, FACS, FCCMClinical Professor, Department of Surgery, University of

Texas Health Science Center at San Antonio; Consultant,U.S. Army Institute of Surgical Research, San Antonio,Texas

[email protected]

Steven S. Raman, MDAssociate Professor, Department of Radiology, David Geffen

School of Medicine, University of California,Los Angeles, California


Sofiya Reicher, MDAssistant Clinical Professor of Medicine, David Geffen

School of Medicine, University of California, Los Angeles,California

[email protected] Bleeding

William P. Schecter, MDProfessor of Clinical Surgery and Vice Chair, University

of California, San Francisco, San Francisco, California;Chief of Surgery, San Francisco General Hospital, SanFrancisco, California

[email protected] of Patients with Environmental Injuries

Paul A. Selecky, MDClinical Professor of Medicine, David Geffen School of

Medicine, University of California, Los Angeles,California; Medical Director, Pulmonary Department,Hoag Hospital, Newport Beach, California

[email protected], Legal, & Palliative/End-of-Life Care Considerations

Shelley Shapiro, MD, PhDClinical Professor of Medicine, David Geffen School of

Medicine, University of California, Los Angeles,California

[email protected] Problems in Critical Care

Elizabeth D. Simmons, MDPartner, Southern California Permanente Medical Group,

Los Angeles, [email protected] Therapy; Bleeding & Hemostasis; Antithrombotic

Therapy

Michael J. Stamos, MDProfessor of Surgery and Chief, Division of Colon and Rectal

Surgery, University of California, Irvine, Orange, [email protected] Abdomen

Samuel J. Stratton, MD, MPHProfessor of Emergency Medicine, University of California

Irvine, Orange, [email protected]

� AUTHORSx

Darryl Y. Sue, MDProfessor of Clinical Medicine, David Geffen School

of Medicine, University of California, Los Angeles,California; Director, Medical-Respiratory Intensive CareUnit, Division of Respiratory and Critical CarePhysiology and Medicine, Associate Chairand Program Director, Department of Medicine,Harbor-UCLA Medical Center, Torrance, California

[email protected] & Principles of Critical Care; Fluids, Electrolytes,

& Acid-Base; Pharmacotherapy; Intensive CareMonitoring; Respiratory Failure; Critical Careof the Oncology Patient; Pulmonary Disease; HIVInfection in the Critically Ill Patient

John A. Tayek, MDAssociate Professor of Medicine-in-Residence, David Geffen

School of Medicine, University of California, Los Angeles,Harbor-UCLA Medical Center, Torrance, California

[email protected]

Timothy L. Van Natta, MDAssociate Professor of Surgery, David Geffen School of

Medicine, University of California, Los Angeles,Harbor-UCLA Medical Center, Torrance, California

[email protected] Infections

Hernan I. Vargas, MDAssociate Professor of Surgery, David Geffen School

of Medicine, University of California, Los Angeles,California; Chief, Division of Surgical Oncology, Harbor-UCLA Medical Center, Torrance, California

[email protected] Disease

Edward D. Verrier, MDWilliam K. Edmark Professor of Cardiovascular Surgery,

Vice Chairman, Department of Surgery, Universityof Washington, Seattle, Washington; Chief, Divisionof Cardiothoracic Surgery, University of Washington,Seattle, Washington

[email protected] Surgery

Janine R. E. Vintch, MDAssociate Clinical Professor of Medicine, David Geffen

School of Medicine, University of California, LosAngeles, Divisions of General Internal Medicine andRespiratory and Critical Care Physiology and Medicine,Harbor-UCLA Medical Center, Torrance, California

[email protected] Failure; Pulmonary Disease

Kenneth Waxman, MDDirector of Surgical Education, Santa Barbara Cottage

Hospital, Santa Barbara, [email protected] Care Monitoring

Mallory D. Witt, MDProfessor of Medicine, David Geffen School of Medicine,

University of California, Los Angeles, California;Associate Chief, Division of HIV Medicine, Harbor-UCLA Medical Center, Torrance, California

[email protected] in the Critically Ill; HIV Infection in the

Critically Ill Patient

Nam C. Yu, MDResident Physician, Department of Radiology, David Geffen

School of Medicine, University of California,Los Angeles, California


Kory J. Zipperstein, MDChief, Department of Dermatology, Kaiser-Permanente

Medical Center, San Francisco, [email protected] Problems in the Intensive Care Unit

xi

PrefaceThe third edition of Current Diagnosis & Treatment: Critical Care is designed to serve as a single-source reference for the adultcritical care practitioner. The diversity of illnesses encountered in the critical care population necessitates a well-rounded andthorough knowledge of the manifestations and mechanisms of disease. In addition, unique to the discipline of critical care isthe integration of an extensive body of medical knowledge that crosses traditional specialty boundaries. This approach isreadily apparent to intensivists, whose primary background may be in internal medicine or one of its subspecialties, surgery,or anesthesiology. Thus a central feature of this book is a unified and integrated approach to the problems encountered incritical care practice. Like other books with the Lange imprint, this book emphasizes recall of major diagnostic features,concise descriptions of disease processes, and practical management strategies based on often recently acquired evidence.

INTENDED AUDIENCEPlanned by two internists and a surgeon to meet the need for a concise but thorough source of information, Current Diagnosis& Treatment: Critical Care is intended to facilitate both teaching and practice of critical care. Students will find its consid-eration of basic science and clinical application useful during clerkships on medicine, surgery, and intensive care unit electives.House officers will appreciate its descriptions of disease processes and organized approach to diagnosis and treatment. Fellowsand those preparing for critical care specialty examinations will find those sections outside their primary disciplines particu-larly useful. Clinicians will recognize this succinct reference on critical care as a valuable asset in their daily practice.

Because this book is intended as a reference on various aspects of adult critical care, it does not contain chapters onpediatric or neonatal critical care. These areas are highly specialized and require entire monographs of their own. Further, wehave not included detailed information on performing bedside procedures such as central venous catheterization or arterial lineinsertion. Well-illustrated pocket manuals are available for readers who require basic technical information. Finally, we havechosen not to include a chapter on nursing or administrative topics, details of which can be found in other works.

ORGANIZATIONCurrent Diagnosis & Treatment: Critical Care is conceptually organized into three major sections: (1) fundamentals of crit-ical care applicable to all patients, (2) topics related primarily to critical care of patients with medical diseases, and (3) essentials ofcare for patients requiring care for surgical problems. Early chapters provide information about the general physiology andpathophysiology of critical illness. The later chapters discuss pathophysiology using an organ system– or disease-specificapproach. Where appropriate, we have placed the medical and surgical chapters in succession to facilitate access to information.

OUTSTANDING FEATURES� Concise, readable format, providing efficient use in a variety of clinical and academic settings� Edited by both surgical and medical intensivists, with contributors from multiple subspecialties� Illustrations chosen to clarify basic and clinical concepts� Careful evaluation of new diagnostic procedures and their usefulness in specific diagnostic problems� Updated information on the management of severe sepsis and septic shock, including hydrocortisone therapy� New information on the serotonin syndrome� Carefully selected key references in Index Medicus format, providing all information necessary to allow electronic retrieval

ACKNOWLEDGMENTSThe editors wish to thank Robert Pancotti and Ruth W. Weinberg at McGraw-Hill for unceasing efforts to motivate us and keepus on track. We are also very grateful to our families for their support.

Frederic S. Bongard, MDDarryl Y. Sue, MD

Janine R. E. Vintch, MDJuly 2008


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� 1

1Philosophy & Principles

of Critical Care

Darryl Y. Sue, MDFrederic S. Bongard, MD

Critical care is unique among the specialties of medicine.While other specialties narrow the focus of interest to a sin-gle body system or a particular therapy, critical care isdirected toward patients with a wide spectrum of illnesses.These have the common denominators of marked exacerba-tion of an existing disease, severe acute new problems, orsevere complications from disease or treatment. The rangeof illnesses seen in a critically ill population necessitateswell-rounded and thorough knowledge of the manifesta-tions and mechanisms of disease. Assessing the severity ofthe patient’s problem demands a simultaneously global andfocused approach, depends on accumulation of accuratedata, and requires integration of these data. Although prac-titioners of critical care medicine—sometimes calledintensivists—are often specialists in pulmonary medicine,cardiology, nephrology, anesthesiology, surgery, or criticalcare, the ability to provide critical care depends on the basicprinciples of internal medicine and surgery. Critical caremight be considered not so much a specialty as a “philoso-phy” of patient care.

The most important development in recent years hasbeen an explosion of evidence-based critical care medicinestudies. For the first time, we have evidence for many of thethings that we do for patients in the ICU. Examples includelow tidal volume strategies for acute respiratory distresssyndrome, tight glycemic control, prevention of ventilator-associated pneumonia, and use of corticosteroids in septicshock (Table 1–1). The resulting improvement in outcomeis gratifying, but even more surprising is how often evi-dence contradicts long-held beliefs and assumptions.Probably the best example is recent studies that concludethat the routine use of pulmonary artery catheters in ICUpatients adds little or nothing to management. Much moreneeds to be studied, of course, to address other unresolvedissues and controversies.

Do intensivists make a difference in patient outcome?Several studies have shown that management of patients byfull-time intensivists does improve patient survival. In fact,

several national organizations recommend strongly that full-time intensivists provide patient care in all ICUs. It can beargued, however, that local physician staffing practices;interactions among primary care clinicians, subspecial-ists, and intensivists; patient factors; and nursing andancillary support play large roles in determining out-comes. In addition, recent studies show that patients dobetter if an ICU uses protocols and guidelines for routinecare, controls nosocomial infections, and provides feed-back to practitioners.

The general principles of critical care are presented in thischapter, as well as some guidelines for those who are respon-sible for leadership of ICUs.

GENERAL PRINCIPLES OF CRITICAL CARE

� Early Identification of ProblemsBecause critically ill patients are at high risk for developingcomplications, the ICU practitioner must remain alert toearly manifestations of organ system dysfunction, complica-tions of therapy, potential drug interactions, and other pre-monitory data (Table 1–2). Patients with life-threateningillness in the ICU commonly develop failure of otherorgans because of hemodynamic compromise, side effectsof therapy, and decreased organ function reserve, espe-cially those who are elderly or chronically debilitated. Forexample, positive-pressure mechanical ventilation is asso-ciated with decreased perfusion of organs. Many valuabledrugs are nephro- or hepatotoxic, especially in the face ofpreexisting renal or hepatic insufficiency. Older patientsare more prone to drug toxicity, and polypharmacy pres-ents a higher likelihood of adverse drug interactions. Just aspatients with acute coronary syndrome and stroke benefitfrom early intervention, an exciting finding is the evidencethat the first 6 hours of management of septic shock are veryimportant.


� CHAPTER 12

Identifying and acting on new problems and complica-tions in the ICU demands frequent and regular review of allinformation available, including changes in symptoms, phys-ical findings, and laboratory data and information from mon-itors. In some facilities, early identification and treatment areprovided by rapid-response teams. Once notified that a patientoutside the ICU may be deteriorating, the team is mobilized

to provide a mini-ICU environment in which critical care canbe delivered early, even before the patient is actuallytransferred.

� Effective Use of the Problem-OrientedMedical Record

The special importance of finding, tracking, and being awareof ICU issues demands an effective problem-oriented med-ical record. In order to define and follow problems effec-tively, each problem should be reviewed regularly andcharacterized at its current state of understanding. For exam-ple, if the general problem of “renal failure” subsequently hasbeen determined to be due to aminoglycoside toxicity, itshould be described in that way in an updated problem list.However, even the satisfaction of identifying a cause of therenal failure may be short-lived. The same patient subse-quently may develop other related or unrelated renal prob-lems, thereby forcing reassessment.

In our opinion, ICU problems must not be restricted to“diagnoses.” We list intravascular catheters and the date they

Table 1–1. Recent developments in evidence-basedcritical care medicine.

Table 1–2. Recommendations for routine patient care inthe ICU.

• Assess current status, interval history, and examination.

• Review vital signs for interval period (since last review).

• Review medication record, including continuous infusions:Duration and doseChanges in dose or frequency based on changes in renal, hepatic,

or other pharmacokinetic functionChanges in route of administrationPotential drug interactions

• Correlate changes in vital signs with medication administration andother changes by use of chronologic charting.

• Integrate nursing, respiratory therapists, patient, family, and otherobservations.

• Review, if indicated:Respiratory therapy flow chartHemodynamics recordsLaboratory flowsheetsOther continuous monitoring

• Review all problems, including adding, updating, consolidating, orremoving problems as indicated.

• Periodically, review supportive care:Intravenous fluidsNutritional status and supportProphylactic treatment and supportDuration of catheters and other invasive devices

• Review and contrast risks and benefits of intensive care.

• Corticosteroids improve outcome in exacerbations of chronic obstruc-tive respiratory disease (COPD).

• A low tidal volume strategy decreases mortality in acute respiratorydistress syndrome (ARDS).

• A lower hemoglobin decision point for transfusion of red blood cellsin many ICU patients results in similar outcome and greatly reduceduse of blood products.

• Tight glycemic control in postoperative surgical patients, most ofwhom did not have diabetes, resulted in less mortality and fewercomplications.

• Elevating the head of the bed to 30–45 degrees in ICU patientsreduces the incidence of nosocomial pneumonia.

• Daily withholding of sedation in the ICU decreases the number ofICU days and results in fewer evaluations for altered level ofconsciousness.

• Daily spontaneous breathing trials lead to faster weaning frommechanical ventilation and shorter duration of ICU stay.

• Low-dose (physiologic) vasopressin may reduce the need for pres-sors in septic shock.

• Fluid resuscitation using colloid-containing solutions is not more ben-eficial than crystalloid fluids.

• Low-dose dopamine does not improve renal function or diuresis anddoes not protect against renal dysfunction.

• Acetylcysteine or sodium bicarbonate protect against radiocontrastmaterial–induced acute renal failure.

• Patients with bleeding esophageal varices have a higher rebleedingrisk if they have infection, especially spontaneous bacterial peritonitis.

• Noninvasive positive-pressure ventilation decreases the need forintubation in patients with COPD exacerbation.

• Noninvasive positive-pressure ventilation is associated with fewerrespiratory infections than conventional ventilation.

• Early goal-directed therapy for sepsis (specific targets for centralvenous pressure, hemoglobin, and central venous oxygen contentduring the first 6 hours of care) decreases mortality.

�PHILOSOPHY & PRINCIPLES OF CRITICAL CARE 3

were inserted on the problem list. This helps us to rememberto consider the catheter as a site of infection if the patienthas a fever. Other “nondiagnoses” on our problem listinclude nutritional support, prevention of deep veinthrombosis and decubitus ulcers, drug allergies, patientpositioning, and prevention of stress ulcers. It may be use-ful to include nonmedical issues as well so that they can bediscussed routinely. Examples are psychosocial difficul-ties, unresolved end-of-life decisions, and other questionsabout patient comfort. Finally, we share the patient’sproblem-oriented record with nonphysicians caring for thepatient, a process that enhances communication, simplifiesinteractions between staff members, and furthers the goalsof patient care.

� Monitoring & Data DisplayA tremendous amount of patient data is acquired in theICU. Although ICU monitoring is often thought of aselectrocardiography, blood pressure measurements, andpulse oximetry, ICU data include serial plasma glucoseand electrolyte determinations, arterial blood gas deter-minations, documentation of ventilator settings andparameters, and body temperature determinations. Takinga daily weight is invaluable in determining the net fluidbalance of a patient.

Flowcharts of laboratory data and mechanical ventilatoractivity, 24-hour vital signs, graphs of hemodynamic data, andlists of medications are indispensable tools for good patientcare, and efforts should be made to find the most effective andefficient ways of displaying such information in the ICU.Methods that integrate the records of physicians, nurses, respi-ratory therapists, and others are particularly useful.

Computer-assisted data collection and display systemsare found increasingly in ICUs. Some of these systemsimport data directly from bedside monitors, mechanicalventilators, intravenous infusion pumps, fluid collectiondevices, clinical laboratory instruments, and other devices.ICU practitioners may enter progress notes, medicationsadministered, and patient observations. Advantages of thesesystems include decreased time for data collection and theability to display data in a variety of formats, including flow-charts, graphs, and problem-oriented records. Such data canbe sent to remote sites for consultation, if necessary.Computerized access to data facilitates research and qualityassurance studies, including the use of a variety of prognos-tic indicators, severity scores, and ICU decision-makingtools. Computerized information systems have the potentialfor improving patient care in the ICU, and their benefit topatient outcome continues to be studied.

The next step is to integrate ICU data with treatment,directly and indirectly. One excellent example is glycemiccontrol so that up-to-date blood glucose measurementswill be linked closely to insulin protocols—at first withthe nurse and physician “in the loop” but potentially with

real-time feedback and automated adjustment of insulininfusions.

� Supportive & Preventive CareMany studies have pointed out the high prevalence of gas-trointestinal hemorrhage, deep venous thrombosis, decu-bitus ulcers, inadequate nutritional support, nosocomialand ventilator-associated pneumonias, urinary tract infec-tions, psychological problems, sleep disorders, and otheruntoward effects of critical care. Efforts have been made toprevent, treat, or otherwise identify the risks for thesecomplications. As outlined in subsequent chapters, effec-tive prevention is available for some of these risks (Table 1–3);for other complications, early identification and aggres-sive intervention may be of value. For example, aggressivenutritional support for critically ill patients is often indi-cated both because of the presence of chronic illness andmalnutrition and because of the rapid depletion ofnutritional reserves in the presence of severe illness.Nutritional support, prevention of upper gastrointestinalbleeding and deep venous thrombosis, skin care, and othersupportive therapy should be included on the ICUpatient’s problem list. To these, we have added glycemiccontrol because of recent data indicating reduced morbid-ity and mortality in medical and surgical patients whoseplasma glucose concentration is maintained in a relativelynarrow range.

Because of expense and questions of effectiveness andsafety, studies of preventive treatment of ICU patients con-tinue. For example, a multicenter study reported that clini-cally important gastrointestinal bleeding in critically illpatients was seen most often only in those with respiratoryfailure or coagulopathy (3.7% for one or both factors).Otherwise, the risk for significant bleeding was only 0.1%.The authors suggested that prophylaxis against stress ulcercould be withheld safely from critically ill patients unlessthey had one of these two risk factors. On the other hand,about half the patients in this study were post–cardiac sur-gery patients, and the majority of patients in many ICUs haveone of the identified risk factors. Thus there may not be suf-ficient compelling evidence to discontinue the practice ofproviding routine prophylaxis for gastrointestinal bleedingin all ICU patients.

Other routine practices have been challenged. For exam-ple, several studies show that routine transfusion of redblood cells in ICU patients who reached an arbitrary hemo-globin level did not change outcome when compared withallowing hemoglobin to fall to a lower value. Further studiesare needed to define the role of other preventive strategies.Important questions include differences in the need forglycemic control, critical differences in the intensity and typeof therapy needed to prevent thrombosis, the optimal hemo-globin for patients with myocardial infarction, and the bene-fit of tailored nutritional support.

� CHAPTER 14

(continued )

Things To Think About Reminders

General ICU Care

1. Nosocomial infections, especially line- and catheter-related.2. Stress gastritis.3. Deep venous thrombosis and pulmonary embolism.4. Exacerbation of malnourished state.5. Decubitus ulcers.6. Psychosocial needs and adjustments.7. Toxicity of drugs (renal, pulmonary, hepatic, CNS).8. Development of antibiotic-resistant organisms.9. Complications of diagnostic tests.

10. Correct placement of catheters and tubes.11. Need for vitamins (thiamine, C, K).12. Tuberculosis, pericardial disease, adrenal insufficiency, fungal sepsis,

rule out myocardial infarction, pneumothorax, volume overload orvolume depletion, decreased renal function with normal serum crea-tinine, errors in drug administration or charting, pulmonary vasculardisease, HIV-related disease.

1. Discontinue infected or possibly infected lines.2. Need for H2 blockers, antacids, or sucralfate.3. Provide enteral or parenteral nutrition.4. Change antibiotics?5. Chest x-ray for line placement.6. Review known drug allergies (including contrast agents).7. Check for drug dosage adjustments (new liver failure or renal failure).8. Need for deep venous thrombosis prophylaxis?9. Pain medication and sedation.

10. Weigh patient.11. Give medications orally, if possible.12. Does patient really need an arterial catheter?13. Give thiamine early.

Nurition

1. Set goals for appropriate nutrition support.2. Avoid or minimize catabolic state.3. Acquired vitamin K deficiency while in ICU.4. Avoidance of excessive fluid intake.5. Diarrhea (lactose intolerance, low serum protein, hyperosmolarity,

drug-induced, infectious).6. Minimize and anticipate hyperglycemia during parenteral nutritional

support.7. Adjustment of rate or formula in patients with renal failure or liver

failure.8. Early complications of refeeding.9. Acute vitamin insufficiency.

1. Calculate estimated basic caloric and protein needs. Use 30 kcal/kgand 1.5 g protein/kg for starting amount.

2. Regular food preferred over enteral feeding; enteral feeding preferredover parenteral in most patients.

3. Increased caloric and protein requirements if febrile, infected, agitated,any inflammatory process ongoing, some drugs.

4. Adjust protein if renal or liver failure is present. Adjust again if dialysisis used.

5. Measure serum albumin as primary marker of nutritional status.6. Give vitamin K, especially if malnourished and receiving antibiotics.7. Consider volume restriction formulas (both enteral and parenteral).8. Give phosphate early during refeeding.9. Control hyperglycemia (glucose



Acute Respiratory Failure, COPD

1. Adequacy of oxygenation.2. Exacerbation due to infection, malnutrition, congestive heart failure.3. Airway secretions.4. Other medical problems (coexisting heart failure).5. Hypotension and low cardiac output response to positive-pressure

ventilation.6. Hyponatremia, SIADH.7. Severe pulmonary hypertension.8. Sleep deprivation.9. Coexisting metabolic alkalosis.

1. Should patient be intubated or mechanically ventilated?Noninvasive mechanical ventilation?

2. Bronchodilators.3. Consider corticosteroids, ipratropium.4. Sufficient supplemental oxygen.5. Antibiotic coverage for common bacterial causes of exacerbations.

Evaluate for pneumonia as well as acute bronchitis.6. Early nutrition support.7. Check theophylline level, if indicated.8. Ventilator management: low tidal volume, long expiratory time, high

inspiratory flow, watch for auto-PEEP. 9. Think about weaning early.

Acute Respiratory Failure, ARDS

1. Sepsis as cause, from pulmonary or nonpulmonary site (abdominal,urinary).

2. Possible aspiration of gastric contents.3. Fluid overload or contribution form congestive heart failure.4. Anticipate potential multiorgan system failure.5. Assess the risks of oxygen toxicity versus complications of PEEP.6. Consider the complications of high airway pressure or large tidal vol-

ume in selection of type of mechanical ventilatory support.7. Low serum albumin (contribution from hypo-oncotic pulmonary

edema).

1. Early therapeutic goal of Fi02

� CHAPTER 16

Table 1–3. Things to think about and reminders for ICU patient care. (continued)

(continued )


Hyponatremia

1. Consider volume depletion (nonosmolar stimulus for ADH secretion).2. Consider edematous state with hyponatremia (cirrhosis, nephrotic

syndrome, congestive heart failure).3. SIADH with nonsuppressed ADH.4. Drugs (thiazide diuretics).5. Adrenal insuffieiency, hypothyroidism.

1. Measure urine Na+, Cl–, creatinine, and osmolality.2. Calculate or measure serum osmolality.3. Volume depletion? Give volume challenge?4. Ask if patient is thirsty (may be volume-depleted).5. Review medication list.6. Primary treatment may be water restriction.7. Consider need for hypertonic saline (carefully calculate amount)

and furosemide.8. Other treatment (demeclocycline).

Hypernatremia

1. Diabetes insipidus (CNS or renal disease, lithium?) 2. Diabetes mellitus.3. Has patient been water-depleted for a long-time?4. Concomitant volume depletion?5. Is the urine continuing to be poorly concentrated?

1. Calculate water deficit and ongoing water loss.2. Replace with hypotonic fluids (0.45% NaCl, D5W) at calculated rate.3. Replace volume deficit, if any, with normal saline.4. Measure urine osmolality, Na+, Cl–, creatinine.5. Does patient need desmopressin acetate (central diabetes insipidus)?

Hypotension

1. Volume depletion.2. Sepsis. (Consider potential sources; may need to treat empirically.)3. Cardiogenic. (Any reason to suspect?)4. Drugs or medications (prescribed or not).5. Adrenal insufficiency.6. Pneumothorax, pericardial effusion or tamponade, fungal sepsis,

tricyclic overdose, amyloidosis.

1. Volume challenge; decide how and what to give and how to monitor.2. If volume-depleted, correct cause.3. Gram-positive or gram-negative sepsis (or candidemia) may also cause

hypotension and shock.4. Give naloxone if clinically indicated.5. Echocardiogram (left ventricular and right ventricular function, pericardial

disease, acute valvular disease) may be helpful.6. Does the patient need a Swan-Ganz catheter?7. Cosyntropin stimulation test or empiric corticosteroids.

Swan-Ganz Catheters

1. Site of placement (safety, risk, experience of operator).2. Coagulation times, platelet count, bleeding time, other

bleeding risks.3. Document in medical record.4. Estimate need for monitoring therapy.5. Predict whether interpretation of data may be difficult (mechanical

ventilation, valvular insufficiency, pulmonary hypertension).

1. Check for contraindications.2. Write a procedure note.3. Make measurements and document immediately after placement.4. Obtain chest x-ray afterward.5. Level transducer with patient before making measurement; eliminate

bubbles in lines or transducer.6. Discontinue as soon as possible.7. Use Fick calculated cardiac output to confirm thermodilution

measurements.8. Send mixed venous blood for O2 saturation.

Upper Gastrointestinal Bleeding

1. Rapid stabilization of patient (hemoglobin and hemodynamics).2. Identification of bleeding site.3. Does patient have a nonupper GI bleeding site?4. Consider need for early operation.5. Review for bleeding, coagulation problems.6. Determine when “excessive” amounts of blood products given.7. Do antacids, H2 blockers, PPIs play a role?8. Reversible causes or contributing causes.

1. Monitor vital signs at frequent intervals.2. Monitor hematocrit at frequent intervals.3. Choose hematocrit to maintain.4. Consider need and timing of endoscopy.5. Consult surgery.6. Patients with abnormally long coagulation time may benefit from fresh-

frozen plasma (calculate volume of replacement needed).7. Platelet transfusions needed?8. Desmopressin acetate (renal failure).


� Attention to Psychosocial& Other Needs of the Patient

Psychosocial needs of the patient must be a major considera-tion in the ICU. The psychological consequences of criticalillness and its treatment have a profound impact on patientoutcome. Leading factors include the patient’s lack of controlover the local environment, severe disruption of the sleep-wake cycle, inability to communicate easily and quickly withcritical care providers, and pain and other types of physicaldiscomfort. Inability to communicate with family members,as well as concern about employment status, activities of dailyliving, finances, and other matters, further inflates the emo-tional costs of being seriously ill. The intensivist and otherstaff members must pay close attention to these problemsand issues and consider psychological problems in the differ-ential diagnosis of any patient’s altered mental status.Adequate yet appropriate sedation and analgesia are manda-tory to preserve the balance of comfort with patient assess-ment and interaction needs.

There is increased awareness of the potential harm topatients and caregivers from the ICU environment. The

noise level is high (reported to exceed 60–84 dB, where abusy office might have 70 dB and a pneumatic drill at 50 feetmight be as loud as 80 dB), notably from mechanical venti-lators, conversations, and telephones but especially fromaudio alarms on ICU equipment. One study found that care-givers were unable to discern and identify alarms accurately,including alarms that indicated critical patient or equipmentconditions.

Sleep disruption deserves much more attention. Very dis-ruptive sleep architecture has been identified in patients inthe ICU. Frequent checking of vital signs and phlebotomywere most disruptive to patients, and environmental factorswere less of a problem to patients surveyed. Most recently, inaddition, the impact of duty hours, sleep, and time off on thecognitive and patient care ability of house officers is beingstudied and reported.

� Understand the Limits of Critical CareAll physicians involved with critical care must be familiarwith the limitations of such care. Interestingly, physiciansand other care providers may have to be reminded that


Fever, Recurrent or Persistent

1. New, unidentified source of infection.2. Lack of response of identified or presumed source of infection.3. Opportunistic organism (drug-resistant, fungus, virus, parasite,

acid-fast bacillus).4. Drug fever.5. Systemic noninfectious disease.6. Incorrect empiric antibiotics.7. Slow resolution of fever (deep-seated infection: endocarditis,

osteomyelitis).8. Infected catheter site or foreign body (medical appliance).9. Consider infections of sinuses, CNS, decubitus ulcers; septic arthritis.

1. Examine catheter sites (old and new), surgical wounds, sinuses, backand buttocks, large joints, pelvic organs, catheters and tubes, skinrashes, hands and feet.

2. Consider pleural, pericardial, subphrenic spaces; perinephric infection;spleen, prostate, intra-abdominal abscess; bowel infarction or necrosis.

3. Abscess in area of previous known infection.4. Review prior culture results and antibiotic use.5. Consider change in empiric antibiotics.6. Culture usual locations plus any specific areas.7. Discontinue or change catheters.8. Consider candidemia or disseminated candidiasis.9. Discontinue antibiotics?

10. Abdominal ultrasound, CT scan, gallium, leukocyte scans.

Pancytopenia (After Chemotherapy)

1. Fever, presumed infection, response to antimicrobials.2. Thrombocytopenia and spontaneous bleeding.3. Drug fever.4. Transfusion reactions.5. Staphylococcus, candida, other opportunistic infections.6. Infection sites in patient without granulocytes may have induration,

erythema, without fluctuance.7. Pulmonary infiltrates and opportunistic infection.

1. Fever workup; see above.2. Special sites: soft tissues, perirectal abscess, urine fungal cultures,

lungs.3. Bronchoscopy with bronchoalveolar lavage.4. Empiric antibiotics, continue until afebrile, doing well, granulocytes

>1000/μL.5. Empiric or directed vancomycin, antifungal drugs, antiviral drugs, antitu-

berculous drugs.6. Check intravascular catheters, bladder, catheter.7. Platelet transfusions, prophylaxis for spontaneous bleeding (or if

already bleeding).

Table 1–3. Things to think about and reminders for ICU patient care. (continued)

� CHAPTER 18

critical illness is and always will be associated with highmorbidity and mortality rates. The outcome of some dis-ease processes simply cannot be altered despite the avail-ability of modern comprehensive treatment. On the basisof medical evidence and after consultation with thepatient and family, some patients will continue to receiveaggressive treatment; for others, withdrawal or withhold-ing of ICU care may be the most appropriate and correctdecision.

It is not surprising that critical care physicians, togetherwith medical ethicists, have played a major role in devel-oping a body of ethical constructs concerned with suchissues as forgoing of care, determination of brain death,and withholding feeding and hydration. The critical carephysician must be familiar with ethical and legal conceptsof patient autonomy, informed consent and refusal, appli-cation of advanced directives for health care, surrogatedecision makers, and the legal consequences of decisionsmade in this context. The cost of care in the ICU will bescrutinized increasingly because of economic constraintson health care.

There is evidence that care in the ICU improves outcomein only a small subgroup of patients admitted. Some patientsmay be so critically ill with a combination of chronic andacute disorders that no intervention will reverse or even ame-liorate the course of disease. Others may be admitted withvery mild illness, and admission to the ICU rather than anon-ICU area does not improve the outcome. On the otherhand, two other subgroups emerge from this analysis of ICUpatients. First, a small subgroup with a predictably poor out-come may have an unexpectedly successful result from ICUcare. A patient with cardiogenic shock with a predicted mor-tality rate of over 90% who survives because of aggressivemanagement and reversal of myocardial dysfunction wouldfall into this group. The other small group consists ofpatients admitted for monitoring purposes only or for minortherapeutic interventions who develop severe complicationsof treatment. In these patients with predicted favorable out-comes, unanticipated adverse effects of care may result insevere morbidity or death.

Areas of critical care outcome research have, for example,focused on the elderly, those with hematologic and othermalignancies, patients with complications of AIDS, andthose with very poor lung function from chronic obstructivepulmonary disease, interstitial lung disease, acute respiratorydistress syndrome, multiorgan failure, or pancreatitis. Muchmore needs to be learned about prognosis and factors thatdetermine outcome, but it is essential that data be usedappropriately and not applied indiscriminately for individualpatient decisions.

Alternatives to current care should be reviewed periodi-cally and considered in every patient in the ICU. Somepatients may no longer require the type of care available inthe ICU; transfer to a lower level of care may benefit thepatient medically and emotionally and may decrease the

risk of complications and the costs of treatment. Admissioncriteria should be reviewed regularly by the medical staff.Similarly, ongoing resource utilization efforts should bedirected at determining which types of patients are bestserved by continued ICU care.

ROLE OF THE MEDICAL DIRECTOROF THE INTENSIVE CARE UNITThe medical director of the ICU has administrative andregulatory responsibilities for this patient care area. Asmedical director, leadership is vital in establishing policiesand procedures for patient care, maintaining communica-tion across health care disciplines, developing and ensuringquality care, and helping to provide education in a rapidlyand constantly changing medical field. The medical direc-tor and the ICU staff may choose to coordinate care in anumber of areas.

� Protocols, Practice Guidelines,& Order Sets

A survey of outcomes from ICUs concluded that establishedprotocols for management of specific critical illnesses con-tribute to improved results. The medical director and medicalstaff, nursing staff, and other health care practitioners maychoose to develop protocols that define uniformity of care orensure that complete orders are written. Some protocols maybe highly detailed, complete, and focused on a single clinicalcondition. An example might be a protocol for treatment ofpatients with suspected acute myocardial infarction—theprotocol could specify the frequency, timing, and types of car-diac enzyme or troponin determination and the timing forECGs and other diagnostic tests. Certain standardized med-ications, such as aspirin, heparin, angiotensin-convertingenzyme inhibitors, and beta-adrenergic blockers, might beincluded in such a protocol, and the physician could chooseto give these or not depending on the particular clinical situ-ation. Protocols are used by many ICUs for community-acquired pneumonia, ventilator-associated pneumonia,sepsis, ventilator weaning, and other clinical situations.

Another type of protocol can be “driven” by critical carenurses or respiratory therapists. In these protocols, nurses ortherapists are given orders to assess the effectiveness and sideeffects of therapy and are given freedom to adjust therapybased on these results. A protocol for aerosolized bronchodila-tor treatment might specify administration of albuterol bymetered-dose inhaler, but the respiratory therapist woulddetermine the optimal frequency and dose on the basis of howmuch improvement in peak flow or FEV1 was obtained andhow much excessive tachycardia was encountered.

The ICU medical director may consider limiting the useof certain medications based on established protocols. Forexample, some antibiotics may be restricted because of cost,toxicity, or potential for development of microbial resistance.


Neuromuscular blocking agents may be restricted to use onlyby certain qualified personnel because of need for specialexpertise in dosing or patient support. Protocols can takeseveral different forms, and patient care in the ICU may ben-efit from their development.

Physician practice guidelines are being developed formany aspects of medical practice. Although some critics ofguidelines argue that these are unnecessarily restrictive andthat elements of medical practice cannot be rigidly defined,practice guidelines may be useful for diagnosing and treatingpatients in the ICU. Guidelines may vary from recommenda-tions for dose and adjustment of heparin infusion for antico-agulation to specific minimum standards of care for statusasthmaticus, unstable angina, heart failure, or malignanthypertension. Practice guidelines will be found commonly inthe ICU of the near future, and ICU directors will be calledon to develop, review, accept, or modify guidelines for indi-vidual ICUs.

The next step beyond practice guidelines is ICU ordersets. Order sets, either paper or paperless, can streamlinepractice guidelines accepted by the ICU staff. Highly recom-mended orders can be preselected, whereas guidance may begiven for other choices. A major feature of order sets will bereduction of errors because the order sets include preprintedmedication names, recommended dosages, and potentialdrug interactions. Computerized order entry goes beyondthe ICU order set, permitting immediate dosage calculations,for example, or other real-time recommendations. Althoughsome have questioned the “one size fits all” nature of ordersets, evidence suggests that there is an increase in the correctapplication of evidence-based treatment with implementa-tion of ICU order sets.

� Quality AssuranceThe ICU medical director participates in quality-of-careevaluation. Quality of care may be assessed by measure-ment of patient satisfaction, analyzing frequency of deliv-ery of care, monitoring of complications, duration ofhospitalization, analysis of mortality data, and other ways.Patient outcome eventually may emerge as the most effec-tive global determination of the quality of care, but suchmeasures suffer from the difficulty in stratifying severity invery complex patients with multiple medical problems. Thedevelopment of protocols and programs to measure andenhance the quality of care is beyond the scope of this pres-entation. However, the medical and nursing leadership of theICU must play key roles in any such projects.

The medical director also plays an important role ingranting privileges to practice in the ICU. Competence inand experience with medical procedures must be investi-gated, documented, and maintained for all physicians whouse the service. While this is especially important for invasiveprocedures such as placement of pulmonary artery cathetersand endotracheal intubation, consideration also should be

given to developing and granting privileges for mechanicalventilator management, management of shock, and othernonprocedural care. Similarly, the skills and knowledge ofnurses, respiratory therapists, and other professionals in theICU should be determined, documented, and matched totheir duties. The ICU medical director has the responsibilityto develop standards for those who care for the patients inthat unit.

Effective quality improvement activities go far beyondsimple data collection and reporting. A dedicated group ofhealth care providers should meet regularly to review thedata, establish trends, and suggest methods for improve-ment. The importance of “closing the loop” in the qualityimprovement process cannot be overstated. Monitoring ofoutcomes after instituting change is an important part of thisactivity and is mandatory if patient care is to be effectivelyand expeditiously improved.

� Infection ControlNosocomial infections are important problems in the ICU,and their prevention and management can provide insightinto the effectiveness of protocols and quality assurancefunctions. Infection control is particularly importantbecause of increased antimicrobial resistance of organismssuch as methicillin-resistance Staphylococcus aureus (MRSA),multidrug-resistant Acinetobacter, vancomycin-resistantenterococci (VRE), and Clostridium difficile. As describedelsewhere, nosocomial infections are often preventable byadherence to procedures and policies designed to limitspread of infection between patients and between ICU staffand patients. The ICU medical director must take the lead inestablishing infection control protocols, including proce-dures for aseptic technique for invasive procedures, stan-dards for universal precautions, duration of invasive catheterplacement, suctioning of endotracheal tubes, appropriate useof antibiotics, procedures in the event of finding antibiotic-resistant microorganisms, and the need for isolation ofpatients with communicable diseases. Consequently, animportant measure of the quality of care being provided isthe nosocomial infection rate in the ICU, especially intravas-cular infections secondary to indwelling catheters. The ICUmedical director should work closely with the nursing staffand hospital epidemiologist in the event of excessive nosoco-mial infections. Often a breach in procedures can be identi-fied and corrected. Importantly, it has been demonstratedthat simple measures to prevent infection at the time ofplacement of intravenous catheters is highly effective.

� Education & ErrorsThe ICU medical director is required to provide educationalresources for the staff of the ICU, including critical carenurses, respiratory therapists, occupational therapists, andother physicians. This may be in the form of lectures, small

� CHAPTER 110

group discussions, audiovisual presentations, or preparedhandouts or directed readings. An effective strategy is tofocus presentations on problems recently or commonlyencountered; recent experience may help to clarify andamplify the more didactic portion. Very often in critical careareas there is a need for personnel to develop skills for usingnew equipment such as monitors, catheters, and ventilators.Appropriate time and feedback should be planned with theintroduction of such equipment before it can be assumedthat it can be used for patient care.

In the teaching hospital, the faculty and attending staff notonly must convey the principles of critical care practice butalso must foster an attitude of rigorous critical review of data,cooperation between medical and other personnel, and atten-tion to detail. The new focus on reduction of medical errorshas greatly changed the way critical care medicine is prac-ticed. The potential for errors is enormous in the ICU. Datashow that changing error reporting from a potentially puni-tive system to one in which future errors are prevented is key.

� CommunicationThe ICU medical director serves as a communication linkbetween physician staff, including primary care and consult-ing physicians, and the nursing and other health care profes-sional staff in the ICU. Most of this communication willoccur naturally as a result of interaction during patient care,quality assurance activities, and other administrative meet-ings. On occasion, further communication is needed toaddress specific complaints, procedures, or policies.Depending on the organization of the hospital, the ICU alsomay be served by a multidisciplinary committee that canparticipate in development of protocols and policies. Thiscommittee may function with respect to a single ICU in ahospital or may have responsibility for standardization ofactivities in several ICUs in the area.

� BurnoutA different topic is burnout among ICU physicians, nurses,and other health care workers. Valuable data are now avail-able about the risks of burnout and its effects on patientcare, productivity, and career planning. Burnout is oneeffect of psychosocial stress and is related to duration ofwork hours, the impact of taking care of patients with criti-cal illness, the effects of poor patient outcome despite max-imal effort, and organizational issues. Intensivists, ICUnurses, and respiratory therapists may experience occupa-tional burnout.

� Outcomes & AlternativesIn many facilities, ICU beds are limited in number, andincoming patients with varying degrees of morbidityoften must be evaluated and compared to determine whomight best be treated in the ICU. A number of published

studies have confirmed that a good proportion of patientsadmitted to ICUs receive diagnostic studies and monitor-ing of physiologic variables only—ie, no therapy that couldnot be given outside the ICU. On the other hand, otherpatients admitted to the ICU do receive such “intensive”therapy, and some of these have better outcomes. BecauseICU beds are a limited resource in all hospitals, ICU med-ical directors must develop familiarity with the overall out-comes and results of patients admitted to their ICU beds.They will be called on not infrequently to make decisionsabout admissions, discharge, and transfer from the ICU,and these decisions at times may be arrived at painfully. Aswith all decisions affecting patient care, the medical direc-tor must weigh the body of medical knowledge available;the wishes of patients, families, and physicians; and thelikelihood or not that intensive care will benefit the patient.At times, these decisions will involve only “medical judg-ment”; at other times, the choice will reflect an ethical,legal, or philosophical perspective.

Specific practice guidelines for individual diseases havebeen developed for the purpose of identifying particularpatients. Recognition that many patients previously admittedto ICUs did not require or receive major diagnostic or thera-peutic interventions led to the design of progressive care,“step-down,” or noninvasive monitoring units in some hos-pitals. Equipped and staffed generally for electrocardiogra-phy, pulse oximetry, and sometimes for noninvasiverespiratory impedance plethysmography—but not forintravascular instrumentation—these units have potential ashighly effective, less costly alternatives to ICUs. A number ofstudies have provided justification for intermediate careunits either as an area for patients leaving the ICU or as anarea devoted to care of certain kinds of medical problems—primarily mild respiratory failure, cardiac arrhythmias, ormoderately severe electrolyte disorders.

CRITICAL CARE SCORINGThe combination of an increasing patient population anddiminished funding for hospital services is creating a needfor optimized distribution of medical resources. This chal-lenge is being met in a number of ways, including regional-ization of care, specialization of critical care facilities (bothbetween and within hospitals), and better allocation of avail-able personnel and equipment. To this end, the intensivistmust be prepared to make both administrative and medicaldecisions about which patients will benefit most from admis-sion to a critical care unit. Data in 1987 indicated that up to40% of patients in ICUs were inappropriately admittedeither because they probably would have died regardless ofthe care provided or because their illnesses were not life-threatening enough to require ICU care. Indeed, a substantialnumber of patients treated in critical care units at teachinghospitals are admitted for “observation and monitoring”only.


Illness scoring has become a popular method for triagewithin and between hospitals. Many such scores have beenintroduced over the past two decades in an attempt to prior-itize illness and injury for ICU admission purposes. Suchscores must be used with full appreciation of their limita-tions. While they are useful for comparing institutional per-formances and outcomes in studies of certain groups ofpatients, great caution must be exercised when applyingthese protocols to individual patients.

The most commonly used trauma and critical care scoresare discussed below and are illustrated in the accompanyingtables.

Glasgow Coma Scale

The Glasgow Coma Scale assesses the extent of coma in patientswith head injuries (Table 1–4). The scale is based on eye open-ing, verbal response, and motor response. The total is the sumof each of the individual responses and varies between 3 pointsand 15 points. Mortality risk is correlated with the total scoreand with a similar Glasgow Outcome Scale. Examination of thepatient and calculation of the score can be accomplished in lessthan 1 minute. The scale is easy to use and highly reproduciblebetween observers. It has been incorporated into several otherscoring systems. The Glasgow Coma Scale is useful for prehos-pital trauma triage as well as for assessment of patient progressafter arrival and during critical care admission.

Trauma Score and Revised Trauma Score

Because of the increasing number of trauma patients admittedto critical care facilities, familiarity with trauma scales is impor-tant. The Trauma Score is based on the Glasgow Coma Scaleand on the status of the cardiovascular and respiratory systems.

Weighted values are assigned to each parameter and summedto obtain the total Trauma Score, which ranges from 1 to 16(Table 1–5). Mortality risk varies inversely with this score.

After extensive use and evaluation of the Trauma Score, itwas found to underestimate the importance of head injuries.In response to this, the Revised Trauma Score (RTS) was intro-duced and is now the most widely used physiologic traumascoring tool. It is based on the Glasgow Coma Scale, systolicblood pressure, and respiratory rate. For evaluation of in-hospital outcome, coded values of the Glasgow Coma Scale,blood pressure, and respiratory rate are weighted and summed(Table 1–6). Better prognosis is associated with higher values.

CRAMS Scale

The Circulation, Respiration, Abdomen, Motor, Speech(CRAMS) Scale is another trauma triage scale that has found

A. Systolic blood pressure B. Respiratory rate C. Respiratory effort D. Capillary refill

>90 470–90 359–69 235 210 10 0

Normal 1Shallow or retractions 0

Normal 2Delay 1None 0

E. 4 GCS points

1. Eye openingSpontaneous 4To voice 3To pain 2None 1

2. Motor response Obedient 6Purposeful 5Withdrawal 4Flexion 3Extension 2None 1

3. Verbal response Oriented 5Confused 4Inappropriate 3Incomprehensible 2None 1

(1 + 2 + 3)14–15 511–13 48–10 35–7 23–4 1

TRAUMA SCORE (A + B + C + D + E) ______

Table 1–5. Trauma Score.

Eye Motor Verbal

4 = Spontaneous 6 = Obedient 5 = Oriented

3 = To Voice 5 = Purposeful 4 = Confused

2 = To pain 4 = Withdrawal 3 = Inappropriate

1 = None 3 = Flexion 2 = Incomprehensible

2 = Extension 1 = None

1 = None

Table 1–4. The Glasgow Coma Scale.

� CHAPTER 112

regional acceptance (Table 1–7). It is frequently used todecide which patients require triage to a trauma center.Patients with lower CRAMS Scale scores would be expectedto require critical care unit admission.

Injury Severity Score (ISS)

The ISS attempts to quantitate the extent of multiple injuriesby assignment of numerical scores to different body regions(head and neck, face, thorax, abdomen, pelvic contents,extremities, and external). A book of codes is available thatprovides information on the scoring of each injury. The worstinjury in each region is assigned a numerical value, which isthen squared and added to those from each of the other areas.The total score ranges from 1 to 75 and correlates with mor-tality risk. The major limitation of the ISS is that it considersonly the highest score from any body region and considersinjuries with equal scores to be of equal importance irrespec-tive of body region. Similarly, since the ISS is an anatomicscore, a small injury with a significant potential for deleteriousoutcome (closed head injury) may lead to the false impressionof a minimally injured patient. ISS is the most commonly usedmeasure of the severity of anatomic injury and provides arough survival estimate for the severely injured patient.

Acute Physiology, Age, Chronic HealthEvaluation (APACHE)

The APACHE scoring system (APACHE III) is probably themost widely used critical care scale. It permits comparisonsbetween groups of patients and between facilities. It was notdesigned to evaluate individual patient outcomes. To thisend, APACHE III was introduced to objectively estimatepatient risk for mortality and other important outcomesrelated to patient stratification. While some centers haveadopted the APACHE III score, it is not used widely exceptfor study of trends in patient groups.

CURRENT CONTROVERSIES& UNRESOLVED ISSUESThe usefulness of scales such as the APACHE III scoring sys-tem remains to be determined long after their introduction.Furthermore, the ability of experienced physicians to makesuch management decisions may be as good as such scalesand perhaps often better. Some authors have concluded thatICU scoring systems can be used to compare outcomeswithin and between ICUs and can provide adequate adjust-ment of mortality rates based on preadmission severity forthe purpose of assessing quality of care.

REFERENCESAngus DC et al: Critical care delivery in the United States:

Distribution of services and compliance with Leapfrog recom-mendations. Crit Care Med. 2006;34:1016–24. [PMID: 16505703]

Curtis JR et al: Intensive care unit quality improvement: A “how-to”guide for the interdisciplinary team. Crit Care Med. 2006;34:211–8. [PMID: 16374176]

Daley RJ et al: Prevention of stress ulceration: Current trends in crit-ical care. Crit Care Med 2004;32:2008–13. [PMID: 15483408]

GlasgowComa

Scale (GCS)

SystolicBlood Pressure(SPB) (mm Hg)

RespiratoryRate (RR)

(Breaths/min) Coded Value

13–15 >89 10–29 4

9–12 76–89 >29 3

6–8 50–75 6–9 2

4–5 1–49 6–9 1

3 0 1–5 0

1RTS = 0.9368 GCSc + 0.7326 SBPc + 0.2908 RRc, where the sub-script c refers to coded value.

Table 1–6. Revised Trauma Score.1 Table 1–7. The CRAMS Scale.1

Circulation

Normal capillary refilll and BP >100 mm HgDelayed capillary refill or 85


Embriaco N et al: High level of burnout in intensivists: Prevalenceand associated factors. Am J Respir Crit Care Med 2007;175:686–92. [PMID: 17234905]

Garland A: Improving the ICU, part 1. Chest 2005;127:2151–64.[PMID: 15947333]

Garland A: Improving the ICU, part 2. Chest 2005;127:2165–79.[PMID: 15947334]

Harris CB et al: Patient safety event reporting in critical care: A studyof three intensive care units. Crit Care Med 2007;35: 1068–76.[PMID: 17334258]

Pronovost P et al: An intervention to decrease catheter-relatedbloodstream infections in the ICU. N Engl J Med 2006;355:2725–32. [PMID: 17192537]

Sinuff T et al: Mortality predictions in the intensive care unit:Comparing physicians with scoring systems. Crit Care Med2006;34:878–85. [PMID: 16505667]

Vincent JL: Evidence-based medicine in the ICU: Importantadvances and limitations. Chest 2004;126:592–600. [PMID:15302748]

DISORDERS OF FLUID VOLUMEIn normal persons, water, distributed between the intracellu-lar and extracelluar spaces, makes up 50–60% of total bodyweight. Critical illness not only can result from abnormalitiesin the amount and distribution of water but also can causestrikingly abnormal disorders of water and solutes.

Distribution of Body Water

Total body water is distributed freely throughout the bodyexcept for a very few areas in which movement of water is lim-ited (eg, parts of the renal tubules and collecting ducts). Waterdiffuses freely between the intracellular space and the extra-cellular space in response to solute concentration gradients.Therefore, the amount of water in different compartmentsdepends entirely on the quantity of solute present in thatcompartment.

The two major fluid compartments of the body are theintracellular space, in which the major solutes are potassiumand various anions, and the extracellular space, for whichsodium and other anions are the major solutes. Sodium movesinto and potassium out of cells passively along concentrationgradients. Thus active transport of sodium and potassium byNa+,K+-ATP-dependent pumps on the cell membrane deter-mines the relative quantities of these cations on the inside andoutside of each cell. The distribution of Na+ and K+ determinesthe relative volumes. In normal individuals, about two-thirds oftotal body water is intracellular and one-third is extracellular.

Addition of solute to either compartment will increase thevolume of that compartment by redistribution of water fromthe compartment of lower solute (higher water) concentrationinto the compartment to which the solute was added. Thusthe solute concentration in both compartments will increase(see “Water Balance”). To restore normal volumes, the bodywill seek to eliminate or redistribute the added solute and cor-rect the increased solute concentration (eg, stimulation of thirstor conservation of water). Similarly, the loss of solute from a

compartment results in a shrinkage of that compartment. Thebody then tries to restore the lost solute to reestablish theoriginal volume and distribution of solute and water.

Distribution of Extracellular Volume

Extracellular volume is divided into the interstitial and theintravascular space. The distribution of water between thesetwo compartments is complex in normal subjects and moreso during disease states in which edema (increase in intersti-tial volume) or accumulation of fluid in normally nearly dryspaces (eg, peritoneal cavity or pleural space) is present.Normally, intravascular volume is maintained by the oncoticpressure of large molecules that are confined to the intravas-cular space, by movement of lymph from the interstitial tothe intravascular space, and by forces that maintain extracel-lular volume. Countering these are the hydrostatic pressuredeveloped by the heart and circulation and interstitial fluidoncotic pressure, which tend to push fluid out of theintravascular space. The volume of the intravascular com-partment determines the adequacy of the circul

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