Empiric antibiotic selection framework
›Antibiotic strategy
›Coverage targets
›Staphylococcus aureus
›MSSA baseline coverage in all regimens
›MRSA coverage if MRSA risk or high unit prevalence
›Gram-negative bacilli
›Pseudomonas coverage in most HAP ICU settings
›Dual antipseudomonal coverage if high mortality risk or MDR risk
›De-escalation plan
›Narrow based on culture and susceptibility
›Stop MRSA agent if MRSA unlikely and cultures negative
›Duration targets
›7 days typical if clinical response and source control adequate
›Longer course only for slow response or complicated infection
›Initial empiric regimens by risk
›HAP without MDR risk and low MRSA risk
›Single antipseudomonal beta-lactam
›Piperacillin-tazobactam IV 4.5 g every 6 hours
›Extended infusion per local protocol when used
›Renal dosing adjustment by creatinine clearance
›Cefepime IV 2 g every 8 hours
›Neurotoxicity risk in renal impairment
›Renal dosing adjustment by creatinine clearance
›Ceftazidime IV 2 g every 8 hours
›Renal dosing adjustment by creatinine clearance
›Meropenem IV 1 g every 8 hours
›ESBL risk or prior ESBL colonization context
›Renal dosing adjustment by creatinine clearance
›HAP with MRSA risk
›Add anti-MRSA agent
›Vancomycin IV 15 mg/kg every 8 to 12 hours
›AUC-guided monitoring target 400 to 600
›Trough-only monitoring not preferred when AUC available
›Linezolid IV 600 mg every 12 hours
›Thrombocytopenia monitoring
›Serotonergic drug interaction awareness
›HAP with MDR risk or high mortality risk
›Dual antipseudomonal agents from different classes
›Beta-lactam backbone
›Piperacillin-tazobactam IV 4.5 g every 6 hours
›Renal dosing adjustment by creatinine clearance
›Sodium load consideration in heart failure
›Cefepime IV 2 g every 8 hours
›Renal dosing adjustment by creatinine clearance
›Encephalopathy risk in renal impairment
›Meropenem IV 1 g every 8 hours
›ESBL coverage
›Seizure risk in predisposed patients
›Second antipseudomonal class
›Levofloxacin IV 750 mg daily
›QT prolongation risk
›Tendinopathy and CNS effect risk
›Ciprofloxacin IV 400 mg every 8 hours
›QT prolongation risk
›Drug interaction review
›Amikacin IV 15 to 20 mg/kg daily
›Therapeutic drug monitoring
›Nephrotoxicity and ototoxicity risk
›Gentamicin IV 5 to 7 mg/kg daily
›Therapeutic drug monitoring
›Nephrotoxicity and ototoxicity risk
›Tobramycin IV 5 to 7 mg/kg daily
›Therapeutic drug monitoring
›Nephrotoxicity and ototoxicity risk
›Add anti-MRSA agent if MRSA risk or unknown prevalence
›Vancomycin IV 15 mg/kg every 8 to 12 hours
›AUC-guided monitoring target 400 to 600
›Renal function monitoring daily in unstable patients
›Linezolid IV 600 mg every 12 hours
›Platelets at least twice weekly during therapy
›Neuropathy risk with prolonged use
Supportive care and complications
›Non-antibiotic management
›Oxygen and ventilation support
›High-flow nasal cannula escalation for increased work of breathing
›If intubated, lung-protective ventilation 6 mL/kg predicted body weight
›Fluids and vasopressors
›Norepinephrine infusion titration to MAP goal
›Add vasopressin if escalating norepinephrine dose
›Airway clearance
›Incentive spirometry when appropriate
›Chest physiotherapy for secretion burden
›Bronchoscopy for mucus plugging or diagnostic sampling
›Pleural space management
›If complicated effusion or empyema, drainage pathway
›Pleural fluid studies if drained
›Antipyretics and analgesia
›Acetaminophen dosing per hepatic function
›Avoid oversedation masking respiratory decline
Stewardship and reassessment
›48 to 72 hour checkpoint
›Clinical response markers
›Temperature trend
›WBC trend
›Oxygen requirement trend
›Micro result integration
›De-escalate to narrowest effective agent
›Stop second antipseudomonal agent if low MDR risk and improving
›Nonresponse evaluation
›If no improvement, CT chest for complications
›If resistant pathogen suspected, broaden based on local antibiogram
›If alternative diagnosis suspected, PE or heart failure workup