Critical Care and Surgical Infection
Sepsis and organ support
Sepsis is life-threatening organ dysfunction from infection, defined by an increase in SOFA score of at least 2. Septic shock is sepsis with persistent hypotension requiring vasopressors and lactate above 2 mmol/L despite fluids. The one-hour bundle: measure lactate, take blood cultures before antibiotics, give broad-spectrum antibiotics, 30 mL/kg crystalloid for hypotension or lactate of 4 or more, and start vasopressors (noradrenaline first-line) to a mean arterial pressure of at least 65 mmHg.
Organ support: lung-protective ventilation for ARDS (6 mL/kg predicted body weight, plateau below 30 cmH2O), renal replacement for refractory acute kidney injury, and early enteral nutrition within 24–48 hours.
Infection control and stewardship
Nosocomial infections include ventilator-associated pneumonia, catheter-related bloodstream infection, catheter-associated urinary tract infection, surgical site infection and Clostridioides difficile. Prevention bundles (hand hygiene, chlorhexidine skin preparation, daily sedation holds, head elevation) matter more than newer antibiotics. Stewardship means right drug, dose, route and duration; de-escalate on culture results; avoid treating colonisation.
Traps
Do not wait for cultures before antibiotics in septic shock. Procalcitonin is not a rule-out test. A normal lactate does not exclude sepsis. Fluid overload is harmful in ARDS and kidney injury; reassess after each bolus. Distinguish the old SIRS criteria from Sepsis-3.
Rule of thumb
If the patient is hypotensive and infected, the clock starts now: cultures, antibiotics and fluids within one hour. Every hour of delay in septic shock increases mortality.