Sepsis and Septic Shock
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Direct answer
Sepsis is life-threatening organ dysfunction caused by a dysregulated host response to infection, defined operationally as suspected infection with a rise of two or more points in the sequential organ failure assessment (SOFA) score, which approximates a doubling of mortality risk. Septic shock is the subset in which vasopressors are needed to maintain a mean arterial pressure of 65 mmHg or above together with a serum lactate above 2 mmol per litre despite adequate fluid resuscitation. Management is the time-critical hour-1 bundle — cultures, broad-spectrum antibiotics, 30 mL per kg crystalloid, vasopressors and lactate — with source control and daily reassessment.
What you must remember
- Sepsis-3 (2016) retired "severe sepsis": organ dysfunction is already part of sepsis; the bedside qSOFA (respiratory rate 22 or more, altered mentation, systolic blood pressure 100 mmHg or less) flags patients in whom sepsis should be considered, while systemic inflammatory response criteria remain useful for screening and infection suspicion.
- SOFA elements: PaO2/FiO2 ratio, platelets, bilirubin, mean arterial pressure or vasopressor need, Glasgow coma scale, and creatinine or urine output — a two-point rise defines sepsis-related organ dysfunction.
- The hour-1 bundle elements, started at recognition: measure lactate (remeasure if above 2 mmol per litre), draw blood cultures before antibiotics, give broad-spectrum antimicrobials within one hour, infuse 30 mL per kg crystalloid for hypotension or lactate of 4 mmol per litre or more, and apply vasopressors during or after fluids to hold mean arterial pressure at 65 mmHg or above.
- Fluids: crystalloids are first choice, with balanced solutions favoured per recent trials; assess responsiveness dynamically and stop when tolerance appears — positive cumulative balance harms in sepsis with acute kidney injury and ARDS.
- Vasopressors and hormones: norepinephrine is first-line (central access preferred, peripheral use short-term acceptable); vasopressin is the usual second agent; adrenaline is reserved for selected refractory shock; dobutamine supports low cardiac output; hydrocortisone 200 mg per day intravenously is added when shock remains vasopressor-dependent.
- Source control is therapy, not an accessory: drain the empyema, remove the infected catheter, relieve the obstructed biliary or urinary tree — ideally within the first hours; de-escalate antimicrobials on culture results and stop empiric cover when infection is excluded.
- Monitoring and endpoints: mean arterial pressure 65 mmHg or above, urine output 0.5 mL per kg per hour or better, lactate clearance, capillary refill and conscious level; survivors need rehabilitation for the physical, cognitive and emotional disability that follows critical illness.
Running the hour-1 bundle on a real patient
A 68-year-old with a urinary catheter arrives febrile, confused, rate 26, pressure 82/48, lactate 4.6. The clock starts at recognition, everything inside the first hour in fixed order. Measure lactate, remeasuring if above 2. Draw two blood culture sets before any antibiotic. Give broad-spectrum antimicrobials within the hour; in an Indian intensive care setting the empiric choice weighs local resistance, a carbapenem or beta-lactam with aminoglycoside where ESBL producers prevail. Infuse 30 mL per kg of balanced crystalloid. Start norepinephrine during or after fluids if mean arterial pressure stays below 65 mmHg. Reassess dynamically — urine output, falling lactate, capillary refill — then pursue source control: change the catheter, drain the collection, decompress the duct. De-escalate when cultures return, and add hydrocortisone only if shock remains vasopressor-dependent.
Where students slip
Words first: Sepsis-3 retired "severe sepsis", and a stem still using it is testing whether you notice. The qSOFA is the second trap — a bedside prompt, not a diagnostic test. On management, the tested answer is 30 mL per kg with reassessment, not open-ended infusion. The pharmacology favourite is norepinephrine first-line with vasopressin second; intramuscular adrenaline belongs to anaphylaxis, and reaching for it in septic shock is the classic planted wrong option.
Frequently asked questions
How does Sepsis-3 define sepsis?
Suspected infection with organ dysfunction — a two-point or greater rise in the SOFA score — replacing the retired category of severe sepsis.
What defines septic shock?
Vasopressor requirement to maintain mean arterial pressure of 65 mmHg or above plus serum lactate above 2 mmol per litre despite adequate volume resuscitation.
What happens within the first hour?
Lactate measurement, blood cultures before antimicrobials, broad-spectrum antimicrobials, 30 mL per kg crystalloid for hypotension or lactate 4 or more, and vasopressors for mean arterial pressure below 65 mmHg.
Which vasopressor is first-line and what is the target?
Norepinephrine, titrated to a mean arterial pressure of 65 mmHg or above, with vasopressin added as the second agent.
When is hydrocortisone added?
When shock persists on adequate vasopressor support — 200 mg per day intravenously — acknowledging faster shock reversal rather than proven survival benefit.
What is source control?
Draining, debriding or removing the anatomic source of infection — abscess drainage, device removal, duct decompression — alongside antimicrobials.