Cardiovascular emergencies in dialysis patients
Professor. Salwa Ibrahim, MD MRCP (UK)Cairo University
Agenda
• Spectrum of CV emergencies in dialysis patients
• Management
Acute Pericarditis
Uremic pericarditis
• Pericarditis either before or within 8 weeks of initiating renal replacement therapy
Pathophysiology
• Pericarditis arises from accumulation of biochemical irritants
• Calcium alterations, high PTH, and uremic toxins have been blamed
Dialysis Related Pericarditis
• Pericarditis after 8 weeks of renal replacement therapy
May be secondary to Inadequate dialysisVolume overloadHypercatabolic conditions Hyperparathyroidism Infection (especially viral)
•
Clinical Presentation
• Chest Pain (41-100%)
• Cough or dyspnea (31-57%)
• Malaise (54-66%) • Weight Loss (40%) • Fever (75-100%)
Diagnosis
• ECG does not show typical ST segment and T wave changes
• Echo is used to assess the size of the effusion
Treatment
• Uremic Pericarditis
• Intensive HD or PD causes rapid improvement
• Systemic anticoagulation should be avoided because of the high risk of hemorrhage
Dialysis Related Pericardial Effusion
• Large (>250cc pericardial effusion, posterior echo free space more than 1cm)
– Drainage
• If hemodynamically unstable needs drainage
• Medium and Small Effusions– Intensive Dialysis (5-7/week)– Serial monitoring by
echocardiography
Ischemic Heart Disease
Risk factors of IHD in dialysis
Traditional risk factors• Age• Male gender• Smoking• Family history• Hypertension• Diabetes mellitus• LVH
Risk factors unique for dialysis• Anemia• Hyperpathyroidism• Uremia• Hyperphosphatemia• Malnutrition• Volume overload• AVF
K/DOQI
• The K/DOQI guidelines recommend to screen ESRD for CVD at the start of dialysis
1. ECG2. Echocardiography3. Coronary artery calcium scoring for selected cases4. Coronary angiography for revascularization candidates
How to manage Angina during dialysis session
History, physical examination, ECG and cardiac enzyme evaluation should be performed.
If dialysis is continued, the administration of oxygen and aspirin, reduction of the desired ultrafiltration and/or blood pump speed, and administration of nitrates or morphine
Prevention
• Anemia management (Hb level 10.5-12.5g/dl)
• Careful PRBCs transfusion if target not met
• Gentle HD to avoid hypotension
Angina during dialysis may be prevented with the administration of nitrates and/or beta blockers prior to the treatment.
The efficacy of these agents is diminished since they commonly result in hypotension, thereby reducing the ability to effectively remove extracellular fluid.
2013 Kidney Disease Global Outcomes (KDIGO) organization clinical practice guideline in on lipid management and
treatment
Acute Myocardial Infarction
• Acute MI is common among ESRD with poor outcome
• Atherosclerosis/arteriolosclerosis contribute to LVH and increased myocardial oxygen demands and reduced coronary perfusion
• Cardiac troponin is misleading in dialysis cases
• Cardiac troponin I is more sensitive than cardiac troponin T or CK-MB
Management
• Prevention : ASA/ clopidogrel, BB, ACEI and nitrates
• Thrombolytics and glycoprotein IIb/IIIa antagonists are beneficial as in general population
• LMWH is superior to UFH but likely to be associated with bleeding
Revascularization
• CABG and angioplasty/ stenting should be considered in urgent cases as in general
Sudden death
Ritz, E. et al. J Am Soc Nephrol 2008;19:1065-1070
Causes of death in the 4D (Die Deutsche Diabetes Dialyse) study
Epidemiology of sudden death in Dialysis
• In the United States Renal Data System database 62% of
cardiac deaths (or 27% of all deaths) are attributable to arrhythmic mechanisms.
• Ventricular fibrillation/tachycardia were the predominant rhythm disturbance
Sudden Death
• Two peaks
First few hours after the first HD of the week( rapid electrolyrte shifts)
Before the first HD of the week end of the long interval- (hyperkalemia)- dead in bed syndrome
Bleyer AJ et al: KI ( 2006) 69: 2268-2273
Risk factors for sudden death in dialysis patients
LVH and heart failure
Coronary artery calcification
Abnormal myocardial structure and function fibrosis, microvessel disease
Electrolyte shifts and hypervolemia (related to dialysis sessions)
Hyperphosphatemia
QT prolonging medication
Sympathetic overactivity and autonomic nerve dysfunction
Low dialysate potassium is associated with the risk of sudden death
Low vitamin D is associated with the risk of SD
Management of cardiac arrest during dialysis
• Check responsiveness• Open airway• Check breathing• Give 2 effectives breaths• Check circulation• Precordial thump• Start CPR• Attach defibrillator
Prevention of sudden death in dialysis
Prevention of sudden death
• Routine very low potassium dialysate should be avoided• beta-blockers and (ACEIs) are proven therapies for reducing
mortality in patients with congestive heart failure. • A small prospective randomized trial of carvedilol in 114
dialysis patients with dilated cardiomyopathy. • They found a significant reduction in CVS mortality and a
trend toward reduction in sudden death• The largest prospective trial of ACEIs in dialysis patients, found
no reduction in CVS events for fosinopril compared to placebo in prevention of sudden death
Implantable cardioverter defibrillators (ICDs)
• Observational data suggest that for cardiac arrest survivors on dialysis, the benefit of ICD implantation is not attenuated by ESRD.
• A 42% reduction in all-cause mortality for patients receiving ICDs, even after adjustment for comorbid illness.
• The role of ICDs for primary prevention of sudden cardiac death in dialysis patients remains uncertain.
Arrhythmia
Cardiac Arrhythmias
• Acute : Ventricular Tachycardia Ventricular Fibrillation
Acute Arrhythmias
• Dialysis session should be terminated
• Urgent Cardioversion as per ACLS Guidelines
• Amiodarone –1stline drug: Ventricular Tachycardia
Intradialytic Hypotension
Definition
• IDH is defined as a decrease in SBP by ≥20 mm Hg associated with symptoms that include: nausea; vomiting; restlessness; dizziness; and anxiety.
• It can induce cardiac arrhythmias, predisposes to coronary and/or cerebral ischemic events.
Higher UF rates are associated with greater CV mortality
Etiology
• Age, anemia• Female Gender • Presence of diabetes mellitus• Hyperphosphataemia• Presence of coronary artery disease • Use of nitrates/antihypertensives• Autonomic neuropathy• Warm dialysate/acetate buffer• Eating during sessions• Pericardial effusion• Septicemia• Occult bleeding• arrhythmia
Pathophysiology
• Interplay of four factors
1. Ultra-filtration
2. Refill blood volume
3. Dialysate (Na+, Ca++, Temp)
4. Patient sensitivity to volume withdrawn
Prevention
• Dry Weight Assessment
• Clinical assessment , IVC diameter
• BNP level
• Echocardiography, ECG
Prevention
• Intradialytic Blood Volume monitoring
• Slow longer dialysis
• Sequential UF/dialysis
• Na+ > or equal 144mEq
• Bicarbonate dialysate
• Low temperature (36.5-35)
• High dialysate calcium
Blood Volume Monitoring
Measures hematocrit in arterial blood
Crit-Line® Technology
Blood volume change – surrogate marker for vascular refilling
Increase in hematocrit relative to decrease in fluid removal
The Inverse Relationship between blood volume and hematocrit
0 1 2 3 4
0
-5
-10
-15
-20
27
29
31
33
35
%B
V (
Lo
ss)
Hc
t
Hct =RCVBV
X 100
Not reliable in clinical studies
Treatment of IDH
• Place patient head down
• 100 cc bolus NS
• Reduce UF to zero
• Midodrine in refractory cases
• 6-week Sertraline therapy (SSRI)
Air embolism
Air embolism
Fatal cause of chest pain and dyspnea during dialysis.
Disconnection of connecting caps and/or blood lines can lead to air embolism in patients being dialyzed with central venous catheters.
Foam in the venous blood line should raise the suspicion that air is entering the dialysis system.
Clinical manifestations
Symptoms of the air embolism depend upon the patient's position
In the seated patient, air tends to migrate into the cerebral venous system without entering the heart leading to loss of consciousness and seizure
Those who are recumbent, air tends to enter the heart and then the lungs leading to dyspnea, cough, chest pain
Management
• Clamp the venous blood line
• Stop the blood pump
• Put the patient in the recumbent position on the left side with the chest and head titled downwards
• Cardiorespiratory support
• Supplemental Oxygen
• Aspiration of air from the atrium/ventricle
Infective endocarditis
Clinical Presentation
• Complication of catheter related bacteremia
• MV/AV affection is common because of calcification
• Fever, leucocytosis, new murmur
Management
• Blood cultures/THE/TEE
• Empirical therapy with vancomycin+aminoglycosides
• Valve replacement (valve destruction, recurrent embolization, failure to respond)