What to check in managing sepsis in patients with Chronic Kidney Disease (CKD)?

Management of Sepsis in Patients with Chronic Kidney Disease

In septic patients with CKD, you must immediately check hemodynamic parameters (MAP, lactate, urine output), obtain blood cultures before initiating broad-spectrum antibiotics within 1 hour, assess volume status for aggressive crystalloid resuscitation (30 mL/kg), and monitor renal function with creatinine and electrolytes to guide antibiotic dosing adjustments and determine need for renal replacement therapy. 1

Immediate Assessment and Monitoring Parameters

Hemodynamic Monitoring

• Measure mean arterial pressure (MAP) targeting ≥65 mmHg 2, 1
• Check central venous pressure (8-12 mmHg goal), pulmonary wedge pressure (12-15 mmHg goal), and central venous oxygen saturation (≥70% goal) 2
• Monitor lactate levels and urine output (target ≥0.5 mL/kg/h) 2, 1
• Place arterial catheter as soon as practical if vasopressors are required 2

Laboratory Parameters to Check

• Obtain blood cultures immediately before antibiotic administration 2, 1
• Measure serum creatinine and calculate creatinine clearance to guide antibiotic dosing 2, 3
• Check electrolytes, particularly potassium, as hyperkalemia may necessitate urgent RRT 2
• Monitor blood glucose levels, initiating insulin when two consecutive values exceed 180 mg/dL 2, 1
• Assess for metabolic acidosis (pH), though sodium bicarbonate is not recommended for pH ≥7.15 2, 1

Renal Function Assessment

• Calculate baseline estimated glomerular filtration rate (eGFR) to classify CKD stage 4
• Monitor for acute kidney injury development using KDIGO serum creatinine criteria 5, 4
• Assess for definitive RRT indications: severe acidosis, hyperkalemia, uremic complications, or refractory volume overload 2, 1, 6

Fluid Resuscitation Strategy

Initial Fluid Administration

• Administer at least 30 mL/kg of crystalloid fluid within the first 3 hours of sepsis recognition, even in patients with CKD or on hemodialysis 1, 7
• Use isotonic crystalloids (0.9% saline or balanced crystalloids) rather than colloids 2, 8
• Do NOT withhold standard fluid resuscitation due to concerns about volume overload—patients with CKD tolerate this bolus without increased complications 7

Volume Status Assessment

• Use fluid responsiveness (dynamic measures) rather than static fluid balance to guide ongoing resuscitation 2, 7
• Do NOT use urine output alone as a guide to administer or withhold further volume loading 2
• Assess for signs of tissue hypoperfusion despite adequate volume status 2

Antimicrobial Management

Timing and Selection

• Initiate broad-spectrum empiric antibiotics within 1 hour of sepsis recognition—each hour of delay decreases survival by 7.6% 2
• Initial treatment options include meropenem, imipenem/cilastatin, or piperacillin/tazobactam monotherapy 2
• Knowledge of local microbiology data is crucial for antibiotic selection 2

Dose Adjustments for Renal Impairment

• For piperacillin/tazobactam with creatinine clearance 20-40 mL/min: reduce to 2.25 g every 6 hours 3
• For creatinine clearance <20 mL/min: reduce to 2.25 g every 8 hours 3
• For hemodialysis patients: 2.25 g every 12 hours plus 0.75 g supplemental dose after each dialysis session 3
• Carefully check and adjust all antimicrobial dosages in patients undergoing RRT, as standard doses may be inadequate 2, 9

Critical Pitfall to Avoid

• Do NOT withhold potentially nephrotoxic antibiotics (e.g., vancomycin, aminoglycosides) due to nephrotoxicity concerns—treatment of sepsis takes absolute priority over potential kidney injury 1, 6, 8
• Ensure adequate resuscitation before attributing worsening renal function to antibiotic nephrotoxicity, as volume depletion is a major contributor 1

Vasopressor Support

Initiation and Selection

• If MAP remains <65 mmHg despite initial fluid resuscitation, initiate norepinephrine (0.1-1.3 µg/kg/min) as first-line vasopressor 2, 1, 8
• Add vasopressin (0.03 U/min) or epinephrine if additional agent needed to maintain MAP 2
• Do NOT use dopamine for renal protection—it does not prevent renal failure and may cause adverse effects 2

Renal Replacement Therapy Considerations

Indications for RRT Initiation

• Initiate RRT only for definitive indications: severe acidosis, hyperkalemia, uremic complications, or refractory volume overload 1, 6, 8
• Do NOT initiate RRT solely for elevated creatinine or oliguria without other indications 1, 6, 8
• In rapidly developing oliguric acute renal failure, do not delay RRT initiation given increased risk of extrarenal complications 2

RRT Modality Selection

• Intermittent hemodialysis (IHD) and continuous renal replacement therapy (CRRT) are equivalent in terms of mortality 2, 1
• Use CRRT in hemodynamically unstable patients to facilitate fluid balance management during aggressive resuscitation 2, 1, 8
• Continue scheduled hemodialysis regimen, but consider transitioning to CRRT if hemodynamically unstable 1
• Increasing RRT dose intensity does not improve mortality or accelerate kidney recovery 2

Metabolic Management

Glucose Control

• Target blood glucose ≤180 mg/dL using protocolized insulin therapy—avoid tight control (80-120 mg/dL) as it increases mortality and hypoglycemia 2, 1, 8
• Monitor glucose every 1-2 hours until stable, then every 4 hours 1, 8
• If blood glucose cannot be measured regularly, do NOT use insulin 2

Acid-Base Management

• Do NOT use sodium bicarbonate to treat metabolic acidosis arising from tissue hypoperfusion with pH ≥7.15 2, 1
• Acidosis may have protective effects and bicarbonate effectiveness is uncertain 2

Additional Critical Monitoring

Nephrotoxin Exposure

• Minimize nephrotoxin exposure—each additional nephrotoxin increases AKI odds by 53%, and combining 3+ nephrotoxins doubles AKI risk 1, 6
• Do NOT use NSAIDs entirely 2, 1
• Avoid furosemide unless hypervolemia, hyperkalemia, or renal acidosis is present 2

VTE Prophylaxis

• Administer pharmacologic VTE prophylaxis with low-molecular-weight heparin (LMWH) or unfractionated heparin 1, 8
• Use dalteparin (preferred LMWH with low renal metabolism) or switch to unfractionated heparin if creatinine clearance <30 mL/min 1, 8

Nutritional Support

• Initiate early enteral nutrition within 48 hours if tolerated, starting with low-dose feeding (up to 500 calories/day) 1
• During initial sepsis phase, limit caloric intake to 20-25 kcal/kg ideal body weight 2

Prognostic Awareness

• Sepsis-associated acute renal failure carries a 70% mortality rate 2, 1
• Patients with CKD discharged after sepsis have significantly higher risks of readmission for AKI, eGFR decline ≥50%, end-stage renal disease, and mortality 5, 10
• AKI stage ≥2 on CKD is strongly associated with adverse long-term outcomes 4