Choking risk among psychiatric inpatients

Choking is a life-threatening and not infrequent occurrence in psychiatric hospitals. There is, however, little information available about the risk factors or methods to prevent choking. We conducted a retrospective analysis of the 8 patients who had a cardiopulmonary arrest due to choking and received resuscitation at our hospital during the 6-year period from April 2005 to March 2011. The study involved 6 males and 2 females, all of whom were patients with schizophrenia taking antipsychotics orally. They were aged from 56 to 79 (mean ± SD: 69.0 ± 7.5 years), with the duration of illness from 28 to 54 years (39.9 ± 7.9 years). In 6 of the 8 cases, choking was diagnosed immediately on the basis of the situation at the time of cardiopulmonary arrest. In the remaining 2 cases, cardiopulmonary arrest was initially unexplained, and choking was only diagnosed subsequently. Choking was caused by bread in all cases. Tracheal intu-bation was carried out in all cases and resulted in successful resuscitation, causing no subsequent change in functions compared with the prechoking condition. All 8 patients had been receiving multiple antipsychotics before the event (mean number of drugs used 2.5 ± 0.7), with a total dose level ranging from 600 to 1800 mg/day chlorpromazine equivalents (mean 1113 ± 341 mg/day). Seven of the 8 patients had mild to moderate involuntary movements, and 5 patients were diagnosed with antipsychotic-induced tar-dive dyskinesia. During the 5-year period before the choking event, 7 of the 8 patients had at least 1 treatment interruption, and some patients had up to 4 interruptions. On average, patients had 2.3 interruptions (mean 2.3 ± 1.2 times) during the preceding 5-year period. Anti-Parkinsonian drugs were used in 6 of the 8 patients with mean dose of 2.6 ± 1.7 mg/day (biperiden equivalents). In 6 patients, hypnotic benzodiazepines had been prescribed at a mean dose of 10.6 ± 9.2 mg/day (diazepam equivalents). Pharyngeal reflex was checked after recovery by depressing the lingual root with a tongue depressor and was found to be was absent in all cases. Six of the 8 patients had frequent abnormal eating behaviors (such as fast eating, hidden eating) before the event. Only 2 of the 8 patients had a history of aspiration pneumonia. The cases of choking in our study were characterized by a high proportion of male patients, long duration of illness, use of multiple antipsychotics, a history of interrupted antipsychotic use, …