Efficacy of dexmedetomidine in preventing postoperative delirium in patients with schizophrenia / 中华麻醉学杂志

ABSTRACT

Objective To evaluate the efficacy of dexmedetomidine in preventing postoperative de-lirium in the patients with schizophrenia. Methods Ninety patients with schizophrenia of both sexes, with American Society of Anesthesiologists physical status Ⅰ or Ⅱ, aged 20-60 yr, weighing 45-90 kg, with a history of long-term use of antipsychotics, scheduled for elective emergency operation under general anes-thesia, were divided into 3 groups ( n=30 each) using a random number table method: high-dose dexme-detomidine group ( group HD ) , low-dose dexmedetomidine group ( group LD ) and control group ( group C) . In HD and LD groups, dexmedetomidine was intravenously injected in doses of 1. 0 and 0. 5 μg∕kg, respectively, over 10 min prior to induction of anesthesia, followed by continuous infusion at 0. 4 and 0. 2μg · kg-1 · h-1 , respectively, until the end of operation. Anesthesia was maintained with propofol, remifentanil and sevoflurane, and bispectral index value was maintained at 40-55. Patient-controlled intra-venous analgesia was performed within 48 h after operation, and visual analogue scale score was main-tained≤3. The end-tidal concentration of sevoflurane ( ETsev) was recorded at 30 min after endotracheal intubation. The sleep quality was evaluated and scored at 6 h and 1, 2 and 3 days after operation. The oc-currence of delirium during emergency from anesthesia and within 3 days after operation was recorded. The occurrence of postoperative adverse reactions such as bradycardia, hypotension and hypoxemia was also re-corded. Results Compared with group C, the ETsev, sleep quality scores at each time point after opera-tion and incidence of delirium during emergency from anesthesia and within 3 days after operation ( 3％) were significantly decreased in group HD, and the ETsev, sleep quality scores at 6 h after operation and in-cidence of delirium during emergency from anesthesia were significantly decreased ( P<0. 05) , and no sig-nificant change was found in the incidence of delirium within 3 days after operation in group LD ( P>0. 05) . The ETsev and incidence of delirium within 3 days after operation were significantly lower in group HD than in group LD ( P<0. 05) . There was no significant difference in the incidence of bradycardia, hypotension or hyoxemia among C, HD and LD groups (P>0. 05). Conclusion Dexmedetomidine given as a loading dose of 1. 0μg∕kg followed by a maintenance dose of 0. 4μg·kg-1 ·h-1 can prevent postoperative delirium effectively in the patients with schizophrenia.