Abstract 14626: Propofol and Dexmedetomidine Related Transient High-grade Symptomatic Av Block

Abstract

Introduction: Dexmedetomidine and propofol are both associated with risk of sinus bradycardia and hypotension. High grade AV block has rarely been reported with these medications. We present a case of high grade AV block (Mobitz II) in the setting of co administration of dexmedetomidine and propofol resulting in hypotension, that resolved with discontinuation of propofol. Case: 85 year old female with history significant for hypertension and CLL was admitted to the ICU with ARDS secondary to COVID-19 requiring mechanical ventilation. Along with management of ARDS, dexmedetomidine and propofol were administered for adequate sedation while trying to limit high dose of propofol. On day one of administration of the combination (16 mcg/kg/min propofol and 0.6 mcg/kg/hr dexmedetomidine), patient developed Mobitz II AV block associated with hypotension with systolic pressure in 60s. Propofol was discontinued and AV block and hypotension resolved. Patient continued to improve and was eventually extubated and transferred to the telemetry floor. Her telemetry during hospital course did not reveal any further high grade AV block and thus patient did not require placement of a pacemaker. Discussion: Optimizing sedation in intubated patients and knowledge of associated adverse effects is warranted to minimize mechanical ventilation time and prevent life threatening complications. Dexmedetomidine has been associated with a reduction in mechanical ventilation duration but an increased risk of bradycardia and hypotension as compared to midazolam and propofol. (1) Hypotension is common with propofol but sinus bradycardia and arrythmias have also been reported. (2) Rarely propofol can precipitate high grade AV block that can be life threatening if not promptly addressed. (3) Co administration of dexmedetomidine and propofol can be associated with exaggeration of individual side effects. Mindfulness of such adverse effects can not only help prevent life threatening complications but also decrease chances of unnecessary pacemaker placements. Conclusion: Propofol though associated with sinus bradycardia, may result in high grade AV block when co-administered with dexmedetomidine that is usually reversible with discontinuation of the offending drug.