(691) Efficacy of Rectal Quetiapine in a Complicated Patient With Delirium and No Enteral Access

Introduction: The removal or reversal of inciting factors and non-pharmacologic therapy remain the mainstay of delirium management in the intensive care unit (ICU). Although routine use of antipsychotics is not recommended, there is mixed evidence to support use to relieve psychiatric symptoms related to suspected neurotransmitter changes noted in delirium. Antipsychotic options for the treatment of agitation, unrelated to pain, are limited in patients without enteral access. Pharmacokinetic data of quetiapine compounded as a rectal suppository or a topical cream have been described but clinical efficacy data are lacking.

Description: A 58-year-old man was admitted status post cardiac arrest complicated by prolonged extracorporeal membrane oxygenation, respiratory and renal failure, refractory hypotension, and a drug-resistant sternal wound infection (treated with meropenem). After tracheostomy and percutaneous endoscopic gastrostomy (PEG) tube placement, a gastro-cutaneous fistula formed between the PEG tube and sternal incision site. A post-pyloric Dobhoff tube was considered for nutrition and medication administration, but given Billroth II anatomy would reflux into the stomach and fistula. The patient was placed on strict nil per os with continuous gastric suction to decrease fistula output.

Psychiatry was consulted for ongoing agitation in the setting of delirium. Pharmacologic options were limited given drug-drug interactions, hypotension, and prolonged QTc. The patient’s delirium and insomnia were previously responsive to enteral quetiapine 100 mg nightly, therefore, the decision was made to trial a quetiapine 50 mg tablet rectally. Of note, rectal administration may yield up to 90% greater plasma concentrations than enteral administration. The patient tolerated rectal quetiapine 50-75 mg nightly for 18 days without further incident of agitation or need for >2 doses of as needed intravenous olanzapine. The patient and nursing staff reported improvement in sleep and symptoms of distress related to delirium.

Discussion: Multiple factors led to limited pharmacologic options for insomnia and hyperactive delirium in a patient with a complicated and prolonged ICU stay. Our experience is the first clinical report of quetiapine tablets administered rectally.