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TRAUMA
Dr Abdollahi
Trauma and associated life-threatening injuries account
for 10% to 15% of all patients hospitalized. Rapid
transport of a trauma victim to a trauma center rather than to the nearest hospital has resulted in improved outcome for the victim.
A level I trauma center is characterized by the
immediate availability of medical and nursing personnel
(emergency medicine physician, trauma surgeon, neurosurgeon, orthopedic surgeon, plastic surgeon, anesthesiologist,critical care specialist, radiologist, and nurses), as well as the facilities needed to treat trauma patients (emergency room, operating rooms, radiology suite, intensive care unit [ICU], central laboratory, and blood bank).
INITIAL EVALUATION
On arrival at the hospital, the patient's airway, breathing, circulation, and neurologic status (Glasgow Coma Scale, computed tomography [CT], magnetic resonance imaging) must be rapidly evaluated with the advanced trauma life support (ATLS) protocol. The first priority is establishment
of an airway and administration of oxygen.
Occasionally, the trauma victim's trachea has been intubated by the paramedic before arrival at the hospital.
Confirmation of tube placement as reflected by a sustained end-tidal CO2 waveform needs to be established and documented immediately on arrival at the hospital.
Early tracheal intubation in selected patients has been
a major factor in decreasing mortality from trauma.
Nasotracheal intubation should not be attempted if there
is the possibility of a basal skull fracture. If airway obstruction exists and tracheal intubation cannot be accomplished, emergency cricothyrotomy or tracheostomy is indicated.
All trauma victims are assumed to be at risk for pulmonary aspiration of gastric contents .
Cervical Spine Injury
In patients with a possible cervical spine injury (present
in 1.5% to 3% of all major trauma victims), orotracheal intubation should be attempted only with the patient's head stabilized in a neutral position (a rigid collar decreases flexion and extension to about 30% of normal and rotation and lateral movement to about 50% of norma!).
CT is the best way to diagnose cervical spine injury, although two thirds of all trauma victims have multiple injuries that may interfere with the ability or safety of performing routine CT.
Thoracic Trauma
Thoracic trauma may involve the lungs or cardiovascular system, or both. An upright inspiratory chest radiograph is preferred for visualization of a pneumothorax (high index of suspicion if rib fractures are present), although the more likely radiograph will be an anteroposterior supine film.
Pneumothorax or hemothorax is treated with a tube thoracostomy (tube placed in the fourth or fifth interspace in the midaxillary line and directed posteriorly and attached to suction). Intrathoracic vascular injury is suggested by a widening mediastinum, whereas lung contusion is predictable when a flail chest is present.
Abdominal Trauma
Abdominal injuries after blunt trauma are most often splenic rupture or laceration of the liver, with both resulting in profound hemorrhage. Intra-abdominal hemorrhage is diagnosed by diagnostic peritoneal lavage (DPL), abdominal ultrasound, or CT. Continued hematuria after placement of a bladder catheter indicates a possible bladder injury and the need for a cystogram or intravenous pyelogram.
Orthopedic Trauma
If suspicion of a pelvic fracture is entertained, the patient should be placed in a pelvic binder and transferred to interventional radiology for an emergency angiogram and possible intravascular embolization instead of rushing the patient to the operating room.
Evaluation of the extremities includes palpation of distal pulses and visual inspection for symmetry of the extremities to detect evidence of bleeding, especially in the thighs after femur fractures. Early immobilization of fractures is indicated.
Management of Anesthesia
General anesthesia is necessary for most trauma patients who require surgical intervention. A "trauma operating room" should be designated and appropriately equipped . There is no ideal anesthetic drug or technique for a trauma patient.
If the patient's trachea has not already been intubated, rapid-sequence induction of anesthesia is indicated. In the presence of hypovolemia, etomidate (0.1 to 0.3 mg/kg IV) or ketamine (1.0 to 3.0 mg/kg IV) is often selected for induction of anesthesia because these drugs are usually able to maintain stable hemodynamics. In patients with suspected or known cervical spine injury, avoidance of excessive head movement during direct laryngoscopy is necessary.
Frequently, the dose of anesthetic tolerated by the
patient is too small to prevent movement, thus necessitating skeletal muscle paralysis with a neuromuscular blocking drug. In this regard, some patients may experience recall of intraoperative events.
Hemodynamic stability results from control of surgical bleeding and restoration of the patient's blood volume. Arterial blood gases, pH, and hematocrit are measured at frequent intervals during anesthesia and surgery. On a less frequent basis, it may be useful to analyze blood for electrolytes, glucose, and coagulation factors.
Fluid Resuscitation
Hypotension plus cellular hypoxia as a result of massive hemorrage is the resone for production of lactic acid . Goal-directed fluid resuscitation should be initiated immediately after the establishment of venous access because it serves to improve poorly perfused organs, including the liver and skeletal muscles.
Initially, administration of a crystalloid solution such as lactated Ringer's or Plasma-Lyte solution restores intravascular fluid volume to help maintain venous return and cardiac output.
SELECTION OF INTRAVENOUS FLUIDS
There is no advantage in using colloid for initial
resuscitation. When hemorrhage is extreme, it will be
necessary to eventually administer blood products.
Dilutional thrombocytopenia may accompany the massive blood transfusion necessary to reestablish intravascular fluid volume, whereas disseminated intravascular coagulation may accompany persistent hypotension.
Rarely, transfusion-related acute lung injury (ALI) can also occur in trauma victims receiving blood transfusions. A fluid warmer device should be used for all intravenous fluids to minimize the likelihood of hypothermia. The ambient operating room temperature should be kept warm. A massive transfusion protocol should be established.
Invasive monitoring, including an intra-arterial and
central venous pressure catheter, is recommended
Transport from the Operating Room
Severely injured patients often require continued postoperative support of major organ function in an rcu, especially mechanical ventilation of the lungs. Patients usually remain intubated, sedated, and paralyzed during transport to the Icu. Appropriate and necessary drugs and equipment should accompany the patient to the Icu. A transport ventilator is preferred if the patient's oxygenation or ventilation (or both) needs to be continuously supported.
Head Injuries
Depressed Linear
Stellate
BasilarSkull Fractures
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TRAUMATIC BRAIN (HEAD) INJURY
Traumatic brain injury (TBl) reflects an insult to the brain
from an external mechanical force (high-energy acceleration or deceleration) that might cause a temporary or permanent impairment of physical and cognitive functions along with changes in mental status. TBl resulting from head injury is the leading cause of death in individuals younger than 45 years and accounts for approximately 40% of all deaths from acute injuries in the United States.
Recognition
The hallmark of closed head injury is loss of consciousness.
CT should be performed early because it is the most important diagnostic test (evidence of increased intracranial pressure [ICP], types of hematoma, and hemorrhage), and the level of consciousness should be classified according to the Glasgow Coma Scale .
Patient age, imaging studies, pupillary response, mean arterial pressure, and initial Glasgow Coma Scale score have been used to predict the overall outcome in TBI patients.
Head Trauma Assessment
Glasgow Scale
Eye Opening
Motor Response
Verbal Response
Head Trauma Assessment
Glasgow Scale--Eye Opening
4 = Spontaneous
3 = To voice
2 = To pain
1 = Absent
Head Trauma Assessment
Glasgow Scale--Verbal
5 = Oriented
4 = Confused
3 = Inappropriate words
2 = Moaning, Incomprehensible
1 = No response
Head Trauma Assessment
Glasgow Scale--Motor
6 = Obeys commands
5 = Localizes pain
4 = Withdraws from pain
3 = Decorticate (Flexion)
2 = Decerebrate (Extension)
1 = Flaccid
Hypotension, hyperthermia, hypoxia, and elevated ICP
are strong predictors of a poor outcome. Patients with a
Glasgow Coma Scale score of less than 8 by definition
have severe TBI, and the mortality rate is about 33% to
55%. In contrast, the mortality rate is lower (around 2.5%) in patients with mild to moderate TBI (Glasgow Coma Scale score of 8 or greater).
CriticaL Care
Critical care of a head-injured patient is based on recognition and treatment of hazardous increases in ICP.Interventions designed to provide cerebral protection and resuscitation have been successful in patients who experience TBI. Invasive monitoring, including intraarterial and central venous catheter, is recommended. Fluid resuscitation to maintain adequate hemodynamics is important.
Low-volume resuscitation with hypertonic solution saline, dextran, or a hemoglobin-based oxygen carrier may be favored over conventional crystalloid therapy. Jugular venous oxygen saturation (Sjo2), potentially representing cerebral tissue oxygenation, may be used to guide therapy.
Administration of barbiturates is recommended when
ICP remains increased despite traditional therapy.
MANAGEMENTOF INTRACRANIAL PRESSURE
A catheter placed through a burr hole in a cerebral ventricle or a transducer placed on the surface of the brain is used to monitor ICP. Normally, ICP is around 15 mm Hg. Cerebral perfusion pressure is the difference between mean arterial pressure and ICP. Patients with a Glasgow Coma Scale score less than 8 should probably have their ICP monitored in a neurosurgery ICU.
An abrupt increase in ICP during continuous monitoring is known as a plateau wave . Painful stimulation in an otherwise unresponsive patient can initiate a plateau wave. Hence, the liberal use of analgesics to avoid pain is indicated even in unresponsive patients. Efforts to minimize the secondary injury from hypoxia or decreased cerebral perfusion will ultimately be the main goal for the care ofTBI patients.
Head Trauma Assessment
Cerebral Perfusion Pressure = Mean Arterial Pressure - Intracranial Pressure
CPP = MAP - ICP
04/19/23 39
TREATMENT
Early tracheal intubation plus mechanical ventilation of
the patient's lungs to avoid arterial hypoxemia has been
shown to improve outcome in the presence of TBI.
Hyperventilation may be deleterious because of cerebral vasoconstriction.
Methods to decrease ICP
1. Posture;
2. Administration of osmotic diuretics,
3. Hypertonic saline,
4. Barbiturates;
5. Institution of cerebrospinal fluid drainage;
6. Craniectomy, lobectomy, and craniotomy.
A frequent recommendation is to treat sustained increases in ICP greater than 20 mm Hg. Treatment may be indicated when ICP is less than 20 mm Hg if the appearance of an occasional plateau wave suggests low intracranial compliance.
POSTUR
Elevation of the head to about 30 degrees is useful in the care of head-injured patients to encourage venous outflow from the brain and thus lower ICP. It should also be appreciated that extreme flexion or rotation of the head can obstruct the jugular veins and restrict venous outflow from the brain. Placement of a central catheter via the subclavian or the internal jugular vein should be guided by the ultrasonic technique.
If central venous pressure monitoring is needed, the patient's neck should be prepared and draped before the patient is placed in the Trendelenburg position. The procedure should be terminated if ICP increases during placement.
Hyperventilation
In the past, deliberate hyperventilation of an adult patient's lungs to a Paco2 between 25 and 30 mmHg to decrease ICP has been recommended. It was presumed that the beneficial effects of hyperventilation of the lungs on ICP reflect decreased cerebral blood flow and resulting decreases in intracranial blood volume.
However, deliberate hyperventilation as a treatment to lower ICP has been questioned because of data showing an increase in mediators, lactate, and glutamate, even with a short period of hyperventilation.
.
Hyperventilation of a head-injured patient's lungs as a technique to reduce ICP is recommended only
in the presence of a mass lesion and impending herniation before definitive surgical intervention
Osmotic Diuretics
Administration of hyperosmotic drugs, such as mannitol
(0.25 to 1 g/kg IV over a period of 15 to 30 minutes),
decreases ICP by producing a transient increase in the
osmolarity of plasma, which acts to draw water from
tissues, including the brain.
However, if the blood-brain barrier is disrupted, mannitol may pass into the brain and cause cerebral edema by drawing water into the brain. The duration of the hyperosmotic effect of mannitol is about 6 hours. The brain eventually adapts to sustained increases in plasma osmolarity such that chronic use of
hyperosmotic drugs is likely to become less effective.
The diuresis induced by mannitol may result in acute
hypovolemia and adverse electrolyte changes (hypokalemia, hyponatremia), thus emphasizing the need to replace intravascular fluid volume with infusions of crystalloid and colloid solutions. A rule of thumb is to replace urine output with an equivalent volume of crystalloids, most often lactated Ringer's solution.
Glucose and water solutions are not recommended because they are rapidly distributed in total-body water, including the brain. If the blood glucose concentration decreases more rapidly than the brain glucose concentration, the brain water becomes relatively hyperosmolar, and water enters the
central nervous system and exaggerates the existing
cerebral edema.
Hypertonic Saline
Hypertonic saline decreases ICP, improves cerebral
perfusion pressure, and enhances hemodynamic function in TBI patients. In addition to its osmotic effect on edematous brain tissue, hypertonic saline also has vasoregulatory, neurochemical, and immunologic effects.
Nevertheless, there is no significant outcome difference
in patients who receive either 7.5% hypertonic solution
or 20% mannitol.
Corticosteroids
Corticosteroids such as dexamethasone or methylprednisolone have been used to decrease ICP for more than 30 years. The mechanism for the beneficial effect of corticosteroids is not known, but it may involve stabilization of capillary membranes or a decrease in the production of cerebrospinal fluid, or both.
Nevertheless, there is no reduction in mortality in patients treated with methylprednisolone in the first 2 weeks after TBl, thus suggesting that steroids should no longer be routinely administered to these patients.
Decompression Craniectomy
Emergency decompression craniectomy is a surgical procedure performed to resolve the elevated ICP and prevent herniation after head insults, especially severe TBI.
Barbiturates
Administration of barbiturates may be recommended
when ICP remains increased despite deliberate controlled hyperventilation of the lungs and drug-induced diuresis.
.
This recommendation is based on the predictable ability
of these drugs to decrease ICP, presumably by decreasing cerebral blood volume secondary to cerebral vasoconstriction and decreased cerebral blood flow. The goal of barbiturate therapy is to maintain ICP at less than 20 mm Hg without the occurrence of plateau waves
Discontinuation of the barbiturate infusion can be considered when ICP has remained in a normal range for 48 hours.
Failure of barbiturates to decrease ICP is a grave
prognostic sign.
A hazard of barbiturate therapy to lower ICP is hypotension, which can jeopardize the maintenance of adequate cerebral perfusion pressure.
Such hypotension is particularly likely in the presence
of decreased intravascular fluid volume. Dopamine
or dobutamine may be necessary in the event of
barbiturate-induced hypotension secondary to myocardial depression. Transthoracic echocardiography can be useful for evaluating cardiac function in head injured patients.
Blunt Cardiac Injury
CHEST INJURIES
Chest injuries are a significant cause of mortality in injured patients and account for 20% of trauma-related deaths in the United States. Both blunt and penetrating chest injuries are treated with similar principles of management. The initial evaluation of patients with chest injuries should emphasize the presence of an adequate airway and ventilation.
Thoracic Trauma
Penetrating Chest Injuries• Majority are stab wounds
or gunshot wounds (GSW)
• Lower mortality rates--less likely to include multiorgan injury
• 85% of penetrating chest wounds can be treated with tube thoracostomy and supportive measures
Penetrating Chest Injuries
• 25,000 deaths per year in the U.S. due to GSWs to the chest
Penetrating Chest Trauma
• Wounds that enter or exit inferior to the nipple or the posterior tip of scapula may perforate the dome of the diaphragm.
• Any penetrating wound such as this should be considered to have an abdominal component until proven otherwise.
Work-up of Penetrating Chest Trauma
• Physical examination– Look, Listen, Feel– Contusions, diminished or absent
breath sounds, SQ emphysema can readily be found
• CXR- best, least expensive and fastest initial evaluation
• Ultrasound-may soon replace CXR as initial radiographic study in chest trauma
• Angiography- to look for great vessel injuries
• CT Scan: for better evaluation of chest wall and parenchyma
• Transesophogeal Echocardiography
Penetrating Chest Injuries
• Operative intervention required for:– Massive or persistent
bleeding– Massive air leak– Tracheobronchial injuries– Esophageal perforation– Cardiac or great vessel
injuries– Post-traumatic empyema
Penetrating Chest Trauma
Wounds that enter or exit inferior to the nipple or the posterior tip of scapula may perforate the dome or the diaphragm.
Any penetrating wound such as this should be considered to have an abdominal component until proven otherwise.
Penetrating Chest Trauma:Indications for Mechanical Ventilation
Intrapulmonary Foreign Bodies
• When left in lung:– 20% developed into
chronic bronchitis– 6% : lung abscess– 10%:
bronchopleural fistula
– 5%: Empyema
Pulmonary Parenchymal Laceration
Massive air leaks and hemorrhage require immediate operation
High Velocity Missile Injuries
• Wounds due to high velocity missiles that travel > 25,000 ft/s are being seen with ever-increasing frequency
• Military and civilian
Operative Intervention for Hemothorax
• As noted previously
• Hemothorax: massive = initial drainage more than 1,000 cc or
• Continuous bleeding of 200 cc/hr for 2 hrs
Blunt Cardiac Injury
EKG (for any blunt chest injury, persistent tachycardia, ST-T changes or ectopy)
Cardiac enzymes (CPK, CK-MB and Troponin I)
Echocardiography (TEE)
Categories of chest wall injuries
• Scapular fractures– 3% of blunt trauma cases– 54% have pulmonary
contusions– 11% have associated
ipsilateral subclavian, axillary or brachial artery injury
• Over 1/3 are missed on initial evaluation
Categories of chest wall injuries
• Flail chest– Fx of at least 4
consecutive ribs in 2 or more places
– Incompetent segment of chest wall large enough to impair respirations
– Paradoxic motion hinders creation of the expected ipsilateral negative inspiratory force
Categories of chest wall injuries
Flail chestCombination of pulmonary contusion and flail
chest has a mortality of 42%
Pulmonary contusion with flail chest: 75% require ventilation
Flail chest ALONE: 48% require ventilation tx
Aggressive respiratory txs and IS with pain control
Pulmonary Contusion
Increase in pulmonary vascular resistance and A-aO2 difference
Diagnosis:
Dyspnea
Tachypnea
Hemoptysis
Cyanosis
Hypotension
Pulmonary Contusion
Treatment
Oxygen to maintain PaO2 above 60 mmHg
Vigorous chest physiotherapy
Use colloids instead of crystalloids when rapid volume replacement is needed
Place PA catheter when large or rapid volume replacement is needed
Use of steroids and antibiotics are controversial
Intra-thoracic Trauma: Great Vessel and Mediastinal Trauma
Aorta
Pulmonary vessels
Tracheobronchial lacerations
Esophageal lacerations
Intra-thoracic Trauma: Great Vessel and Mediastinal Trauma—
Work-upPlain CXR to identify thoracic aorta injuries
Look for air in the mediastinum
Persistent airleak should cue into:
Bronchopulmonary or tracheobronchial injury
Mediastinitis, tube feedings in chest tube or saliva in chest tube should cue into:
Esophageal injury
Intra-thoracic Trauma: Great Vessel and Mediastinal Trauma—
Work-upBronchoscopy
Esophagoscopy
CT
Serial CXR
Initial CXR of Concern
Indications for Angiography
Lateral deviation of the NGT in esophagus
Widened mediastinum (>8cm)
Loss of visualization of the aortic knob
Hematoma of the Left cervical pleura (pleural cap)
Depressed left main stem bronchus
Rt lateral deviation of the trachea
Indications for Angiography
• Widened mediastinum (>8cm)
Indications for Angiography
• Forward displacement of the trachea on the lateral CXR
• Fx of the 1st or 2nd rib• Massive chest trauma w/
multiple rib fx• Fx or dislocation of the
thoracic spine• Major deceleration injury
The chest radiograph is analyzed for the presence
of pneumothorax, hemothorax, pulmonary contusion,
deviation of the tracheobronchial tree, widening of the
mediastinum, and abnormal mediastinal shadows. These findings determine the need for additional diagnostic or therapeutic interventions.
Tension Pneumothorax
Tension pneumothorax is a relatively common cause of
respiratory distress in a patient with chest trauma. Placement of a chest tube without waiting for a chest radiograph is warranted in patients with penetrating chest trauma who are in significant respiratory distress or have systemic hypotension. Patients with chest trauma may also have significant hemorrhage that requires prompt administration of crystalloid solutions and blood.
Urgent Thoracotomy
The need for urgent thoracotomy because of chest trauma is rare. In fact, because lobectomy and pneumonectomy are associated with high mortality in trauma patients, treatment techniques have been developed that emphasize rapid and minimal lung resection.
Guidelines for the need for emergency thoracotomy include an initial blood loss of 1500 mL on placement of the chest tube and continued bleeding of 200 to 300 mL/hr. Additional indications for thoracotomy consist of injuries to the heart or great vessels and tracheal, bronchial, or esophageal injuries. Diaphragmatic repair is usually performed via an
abdominal approach.
MANAGEMENT OF ANESTHESIA
Before induction of general anesthesia for trauma
patients undergoing emergency thoracotomy, it is
critical to exclude the presence of a pneumothorax that
could become a tension pneumothorax with the institution of mechanical ventilation of the patient's lungs.
Management of these patients often includes an intra arterial and central venous pressure catheter, as well as peripheral large-bore intravenous catheters placed above the diaphragm. Because of the presence of lung injury, these patients' lungs need to be ventilated with low tidal volume ventilation (6 mL/kg ideal body weight) and a small amount of positive end-expiratory pressure.
Placement of a double-lumen endotracheal tube to
perform one-lung ventilation may be warranted for lung
resection or repair of the esophagus or large intra thoracic vessels. These patients are usually transferred to the Icu with the trachea intubated and the lungs mechanically ventilated.
ABDOMINAL INJURY
Abdominal injury accounts for a small, but significant
number of trauma-related deaths, especially when the
abdominal injury is not recognized. One of the major
reasons for a fatal outcome is that the peritoneal cavity
and retroperitoneal space are potential reservoirs for
large and occult blood loss.
During initial evaluation of the trauma victim, peritoneal signs of abdominal trauma are often subtle and difficult to diagnose because of the intense pain associated with extra-abdominal injuries or
because of the presence of TBl and altered mental status.
Thus, during the initial evaluation of a severely traumatized patient, the first step is to diagnose the presence of abdominal trauma.
Classification
Traumatic abdominal injuries are classified as penetrating or blunt injuries. Penetrating injuries associated with overt signs of peritoneal irritation or acute blood loss (or both) are clear indications for surgery.
If there is no violation of the peritoneum, local exploration is usually sufficient. Blunt trauma is generally caused by collisions or falls. The severity of the injury is determined by the acceleration-deceleration process sustained by the victim.
The organs most commonly injured are the liver, spleen, and kidneys.
Diagnosis
Ultrasound performed in the emergency department is
an important diagnostic tool for detecting the presence
of an abdominal injury, including the presence of blood
in the abdomen. Diagnostic peritoneal lavage (DPL) is a
sensitive method for detecting the presence of serious
intra-abdominal bleeding.
The classic indication for DPL is suspicion of intra-abdominal bleeding associated with arterial hypotension. In stable patients, an abdominal
CT scan with radiocontrast is often performed instead of
DPL. A CT scan allows the clinician to detect the location and magnitude of intra-abdominal injuries in hemodynamically stable patients.
CT may also be important for investigating genitourinary injuries when intravenous radiocontrast is used.
Management of Anesthesia
Severe abdominal injuries require general anesthesia and often placement of an intra-arterial and central venous pressure catheter. In many institutions, a large-bore catheter is placed in a femoral vein on arrival at the emergency department..
It is important to recognize that the femoral venous catheter should not be used for rapid blood transfusions when abdominal venous injuries are suspected.
It is good practice to place an additional large-bore catheter above the diaphragm for rapid intravenous administration of volume to these patients
PELVIC FRACTURES
Pelvic fractures are the third most frequent injury in
victims of motor vehicle accidents and are often associated with other abdominal injuries. The overall mortality from pelvic fractures is between 15% and 50%, depending on the extent of the injuries. The combination of pelvic fracture and severe TBI has high mortality..
The initial treatment of pelvic fractures associated with bleeding is nonoperative, and they are managed by angiographic embolization.
In addition to this treatment, patients may require external fixation of the fractures to allow mobilization.
Alternatively, stabilization of the pelvis can be
achieved with the use of military antishock trousers (MAST).
The anesthesiologist has a critical role to play during the initial resuscitation of patients with severe pelvic fractures.
These patients frequently require the administration
of large volumes of blood, thus necessitating activation of the massive transfusion protocol. As with other abdominal injuries, it is also imperative to place large-bore intravenous catheters above the diaphragm.
BLUNT SPLENIC AND LIVER INJURIES
There has been a change in the management of blunt
splenic and liver injuries toward a more conservative
approach. Patients without signs of hemodynamic instability or intra-abdominal bleeding can be monitored closely in the ICU after the initial evaluation and placement of large-bore intravenous catheters.
Usually, it is mandatory to obtain sequential hematocrit measurements during the first 24 hours and to frequently examine these patients for detection of any signs of new intra-abdominal bleeding.
Furthermore, these patients are at risk for abdominal
compartment syndrome because of the increased vascular permeability associated with severe trauma.
Thermal (Burn ) injury
Continuous improvement in the care of burned patients
for the last 30 years has resulted in an increase in survival after the initial insult. It is not uncommon to see patients with burns affecting 70% to 80% of the total body surface area to survive this injury.
Critical factors that affect mortality in these patients include age older than 60 years, third-degree burns over more than 40% of the total body surface area, and smoke inhalation. Mortality increases in proportion to the number of risk factors present. In addition, the mortality rate of burned patients is also affected by the presence of significant coexisting diseases and delays in treatment.
Initial Evaluation
The initial clinical evaluation of an acutely burned patient includes a careful analysis of the burned body surface area, the depth of the burns, the mechanisms of injury (electrical, smoke inhalation), and the presence of associated traumatic injuries . Furthermore, information should be obtained as soon as possible about the presence of significant comorbid conditions that may affect the survival of a severely burned patient.
04/19/23 113
Initial Fluid Resuscitation
The initial treatment of burned patients includes an
assessment of the fluid resuscitation requirements for the first 24 hours. The most commonly used guideline for calculation of fluid replacement needs is the Parkland formula (4 mL/kg/% burn); the replacement fluid is given as lactated Ringer's solution. Half the volume should be given during the first 8 hours and the other half during the following 16 hours.
After the first 24 hours, protein repletion is frequently needed and is typically provided by 5% albumin (0.3 to 0.5 mL/kg/total body surface area of burned tissue). In addition to colloid replacement, a
burned patient should receive maintenance fluid, which
can be estimated as basal maintenance (1500 mL/m2 +evaporative water loss [(25 + % burn) x m2 x 24]).
04/19/23 116
Clinical evidence of adequate fluid resuscitation includes normalization of systemic blood pressure, urine output (> 1 mL/kg/hr), and values for blood lactate, base deficit,plasma sodium concentration, and central venous pressure
Urine output is not a reliable guide to the adequacy of
resuscitation after the first 24 to 48 hours following a
burn injury because of the presence of osmotic diuresis
associated with glucose intolerance and high caloric feeding.
Furthermore, a non-anion gap arterial base deficit may
reflect the excessive intravenous administration of 0.9%
sodium chloride solution.
In elderly patients or those with significant preexisting cardiac disease, hemodynamic parameters should be monitored carefully, possibly with placement of a pulmonary artery catheter, to prevent the
development of acute congestive heart failure as a result of vigorous fluid resuscitation. Rapid fluid resuscitation can be associated with the development of severe tissue edema compromising limb perfusion or an abdominal compartment syndrome.
Management of Anesthesia
Burned patients will require general anesthesia, initially
for escharotomy of the limbs, thorax, and/or abdomen and later for excision of the burned skin and grafting. If the injuries do not preclude conventional airway management, standard anesthesia induction and tracheal intubation procedures are appropriate.
However, succinylcholine should not be administered when the burn injury is older than 24 hours because drug-induced hyperkalemia may result in cardiac arrest. The trachea of a severely burned patient should remain intubated after the initial escharotomies because the aggressive fluid management that occurs during the following 24 to 48 hours to compensate for the burn shock often causes airway edema and compromise.
The patient's lungs should be ventilated with low-tidal volume ventilation (6 mL/kg ideal body weight)
if smoke inhalation injury or acute lung injury from another origin is present. Placement of an intra-arterial and central venous catheter should be done under sterile conditions.
.
Particular attention should be paid to the impaired
temperature regulation associated with severe burns.
Excision of burned skin is accompanied by substantial
blood loss, which can be estimated at 0.5 mL/cm2 of burned area
At the conclusion of surgery, transport of severely
burned patients to the ICU should be planned carefully
because accidental extubation during the transport of
these patients may result in an inability to ventilate the
patient's lungs by mask because of face and neck burns.
Lean body weight or mass
Ideal Body Weight (men) = 50 + 2.3 ( Height(in) - 60 ) ( Devine formula)
Ideal Body Weight (women) = 45.5 + 2.3 ( Height(in) - 60 ) (Robinson formula)
04/19/23 125
Lean body weight or mass
Ideal Body Weight (men) = 50 + 2.3 ( Height(in) - 60 ) ( Devine formula)
Ideal Body Weight (women) = 45.5 + 2.3 ( Height(in) - 60 ) (Robinson formula)
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