Prevalence of i.v. thiopental use in psychiatric emergency settings in Japan

Because i.v. barbiturates such as thiopental carry the risk of apnea and laryngeal spasm in asthmatic patients, reducing the use of barbiturate in emergency situations is important. The purpose of the present study was therefore to investigate the prevalence of i.v. thiopental as a choice of sedation in behavioral emergency settings, we conducted a cross-sectional multicenter study.

Psychiatric emergency departments of seven hospitals were studied during a 4-month period. Patients with a score >15 on the Excited Component of the Positive and Negative Syndrome Scale (PANSS-EC) who received i.v. medication were included in the study. Drugs were chosen according to the Japanese guidelines, in which the first injection was either haloperidol or benzodiazepine in accordance with clinical requirements. A second injection, which was the opposite drug to the first injection was administered as needed. Only when excitement obviously increased following the first injection, which was considered uncontrollable without thiopental according to expert experience, was thiopental given as a second injection. A total of 137 patients were included. The mean age was 40.4 years (SD 13.1), and the rate of male gender, drug-naïve, and F2 (schizophrenia, schizotypal and delusional disorders) on the ICD-10 were 48.9%, 29.9%, and 65.7%, respectively.

The rate of patients treated with thiopental as a second injection was 8.0% (n = 11). All of the first injections in patients treated with thiopental were not haloperidol but benzodiazepines (P = 0.0072).

Because this multicenter study has an epidemiological character, the prevalence of i.v. thiopental use in psychiatric emergency settings in Japan is considered to be 8.0%.