Comparison of the Effects of Haloperidol and Midazolam on Reduction of Adverse Psychotomimetic Reactions after Induction of Anesthesia with Ketamine in Adults

As an anesthetic agent, ketamine is associated with a number of adverse psychological reactions after patient recovery (Motamed et. al., 2012). Midazolam is currently used to mitigate such adverse reactions. However, they still cause discomfort in patients and sometimes their next of kin. The present study aimed to compare the effect of midazolam and haloperidol on decreasing these adverse psychological reactions. In this clinical trial, patients who were subjected to anesthesia induction by ketamine were randomly divided into haloperidol, midazolam, and distilled water (as control) groups. All patients underwent orthopedic surgery with a maximum duration of 2 hours. After the recovery of the patients, a questionnaire was completed by the anesthesiologist. In addition to demographic data, the questionnaire included a number of questions about adverse psychological reactions such as inaudible speech, uncontrollable crying and laughter, strange feelings, illusions, anxiety, and agitation. After completing the questionnaires, the data were introduced into SPSS and analyzed with statistical tests. A total of 60 patients including 30 men and 30 women were enrolled in the study. The mean age of the patients was 32.9 +/- 9.5 years ranging from 16 to 50 years. Twenty patients received the premedication (pre-anesthetic drug) haloperidol before the induction of anesthesia, 26 patients received midazolam, and 14patients received distilled water. The patients were similar in terms of age, gender, and ASA group. The recovery time for midazolam and haloperidol was significantly longer than that of distilled water (p=0.02). In addition, the number of adverse psychological reactions were significantly higher in the midazolam (p=0.02) and haloperidol (p=0.04) groups than in the distilled water group. However, they occurred less often in midazolam group than the haloperidol group with no significant difference. Haloperidol can reduce the adverse psychological reactions of ketamine, but this reduction is not as prominent as midazolam.