Antibiotic Stewardship in the ICU: Practical Decisions on Who, When, and How to De-escalate

A recent review published in Critical Care finds that clinicians should deliver immediate broad‑spectrum antibiotics for patients with septic shock, whereas rapid, targeted evaluation permits selective initiation in other sepsis presentations. By contrast, septic shock requires time‑sensitive empiric MRSA and pseudomonal coverage, while non‑shock sepsis allows a measured 3–5 hour assessment using rapid diagnostics, procalcitonin trends, and structured ADE workflows to enable early narrowing.

Patient‑level triggers that justify empiric MRSA or antipseudomonal coverage include prior colonization with resistant organisms, recent broad‑spectrum antibiotics, recent healthcare exposures (including prior hospitalization or long‑term care), and severe presenting illness; institutional antibiogram thresholds (pragmatically ~10% carriage/likelihood for life‑threatening infections) guide the decision. Moreover, routine combination empiric therapy does not confer mortality benefit and increases nephrotoxicity, so clinicians should reserve combination regimens for narrowly defined high‑risk situations (e.g., suspected highly resistant Gram‑negative pathogens where early concordant coverage is critical, or specific invasive infections such as endocarditis or necrotizing soft‑tissue infection — aztreonam + ceftazidime‑avibactam is an example for suspected MBL).

That tradeoff makes rapid diagnostics and biomarkers essential at the bedside. Daily ADE and structured stewardship workflows reduce antibiotic exposure without harm and may lower mortality. Consequently, immediate operational levers that change bedside prescribing include standardized order‑sets with stop‑dates, embedded pharmacist and microbiology review on rounds, targeted CDS with audit‑and‑feedback, and protocolized procalcitonin use tied to clinical criteria.