UMEM Educational Pearls

Lorazepam Infusions

  • There is some literature that propofol may be better for sedation in the mechanically ventilated patient, yet many emergency physicians still do not have access to the medication
  • Lorazepam infusions are frequently used in many EDs for sedation of the mechanically ventilated patient
  • Patients receiving continuous infusions of lorazepam are at risk for propylene glycol toxicity
  • Propylene glycol toxicity primarily causes a metabolic acidosis and acute tubular necrosis
  • Critically ill patients with renal or hepatic dysfunction are at increased risk of toxicity
  • Monitoring propylene glycol levels are impractical
  • Rather, check the osmol gap: a gap > 10 - 15 reflects significany propylene glycol accumulation
  • Hemodialysis effectively removes propylene glycol


Devlin JW, Roberts RJ. Pharmacology of commonly used analgesics and sedatives in the ICU: benzodiazepines, propofol, and opioids. Crit Care Clin 2009;25:431-49.