US EPA

3036797 

Journal Article 

Propylene glycol-induced lactic acidosis in a patient receiving continuous infusion pentobarbital 

Miller, MA; Forni, A; Yogaratnam, D 

2008 

Yes 

Annals of Pharmacotherapy
ISSN: 1060-0280
EISSN: 1542-6270 

42 

10 

1502-1506 

English 

18698010 

10.1345/aph.1L186 

WOS:000259545900019 

OBJECTIVE: To report a case of probable propylene glycol (PG) toxicity in a patient receiving continuous infusion of pentobarbital for refractory status epilepticus.

CASE SUMMARY: A 59-year-old woman with a declining mental status was admitted to the intensive care unit for management of status epilepticus. After failing to achieve the therapeutic endpoint of electroencephalogram burst suppression with a continuous infusion of propofol, the sedative regimen was changed to continuous infusion of pentobarbital. The patient received a loading dose of 450 mg (5 mg/kg), and the maintenance infusion was titrated to a dose of 10 mg/kg/h to achieve burst suppression. Twelve hours after the pentobarbital infusion was started, the patient developed an anion gap metabolic acidosis, elevated serum lactate level, hyperosmolality, and increased osmolal gap. The pentobarbital infusion was discontinued, and the patient's acidosis and hyperosmolality resolved.

DISCUSSION: Pentobarbital contains 40% v/v of PG, which was thought to be a potential source of the patient's metabolic derangements. Reports of toxicity with drugs containing PG, particularly intravenous lorazepam, have been well described in the literature. What we describe, however, is one of few reports involving intravenous pentobarbital. The Naranjo probability scale supports a probable drug-related adverse event in our patient.

CONCLUSIONS: PG toxicity is a potential complication associated with intravenous pentobarbital. Practitioners should be aware of the PG content of pentobarbital and should be familiar with the signs and symptoms associated with PG toxicity. 

lactic acidosis; pentobarbital; propylene glycol; toxicity