Oral preanaesthetic medication for children: double-blind randomized study of a combination of midazolam and ketamine vs midazolam or ketamine alone

Abstract

Anxiolysis and sedation with oral midazolam are common practice in paediatric anaesthesia. However, good or excellent results are seen in only 50-80% of cases. For this reason, we investigated if addition of a low dose of oral ketamine (MIKE: ketamine 3 mg kg-1, midazolam 0.5 mg kg-1) resulted in better premedication compared with oral midazolam 0.5 mg kg-1 or ketamine 6 mg kg-1 alone, in a prospective, randomized, double-blind study. We studied 120 children (mean age 5.7 (range 2-10) yr) undergoing surgery of more than 30 min duration. After oral premedication in the ward and transfer, the child's condition in the induction room was evaluated by assigning 1-4 points to the quality of anxiolysis, sedation, behaviour at separation from parent and during venepuncture (transfer score). On days 1 and 7 after operation, parents were interviewed for changes in behaviour (eating, sleep, dreams, toilet training), recollection and satisfaction, using a standardized questionnaire. The groups were similar in age, sex, weight, intervention and duration of anaesthesia. The transfer score was significantly better in the MIKE group (12.5 (95% confidence interval (CI) 11.9-13.1)) than in the ketamine or midazolam groups (10.6 (9.8-11.4) and 11.5 (10.7-12.3), respectively). Success rates for anxiolysis and behaviour at separation were greater than 90% with the combination, approximately 70% with midazolam and only 51% with ketamine alone. The incidence of salivation, excitation and psychotic symptoms was low in all groups. Vertigo and emesis before induction were significantly more frequent after ketamine premedication. During recovery, there were no differences in sedation or time of possible discharge. After 1 week, parents reported nightmares (ketamine five, midazolam three, MIKE one), restless sleep (five/four/four) or negative memories (three/four/one). There were no major or continuing disturbances in behaviour or development. In summary, significantly better anxiolysis and separation were observed with a combination of ketamine and midazolam, even in awake children (sedation was not successful according to the preset criteria), than with midazolam or ketamine alone. Duration of action and side effects of the combination were similar to those of midazolam. The combination of both drugs in strawberry flavoured glucose syrup (pH 4.5 approximately) is chemically stable for 8 weeks.

Oral premedication in children: A randomized study of a combination of oral midazolam, ketamine with atropine vs midazolam and atropine vs ketamine and atropine

“…[16][17][18][19] Funk et and Warner et al in their study observed better anxiolysis on separation from parents with combination of midazolam and ketamine than either of the drugs alone and the same is strengthened by our study result. 18,19 We chose 30 minutes from administration of premedication to assess sedation and anxiety level, as previous studies have reported that 15 to 30 minutes time interval provided optimal efficacy of midazolam. 6,20 In our study we found a significant improvement in sedation and anxiolysis with the combination than with midazolam or ketamine alone.…”

A double blinded comparative study of oral premedication in children with midazolam alone or in combination with ketamine

“…19 In a similar study performed by Ghai B et al showed that uniform and acceptable sedation scores were seen in both the groups (group-M 95.9%; group-MK 97.96%). 20 Present study results were also comparable with Foroutan A et al where in their comparative study exhibited satisfactory sedation compared with midazolam (86%) and ketamine (83%) groups.…”

“…19 Whereas in a similar study by Ghai B et al the mean postanesthesia recovery time, i.e. time to achieve Aldrete score of 10 was comparable between the two groups (128±35 minutes in group M and 120±24 minutes in group MK).…”

“…But there was no significant difference between the two groups. 19 The higher percentage of success in both group was probably due to use of EMLA cream in their study.…”

Ansiedade, a criança e os pais

“…A cetamina pode provocar agitação e alucinação durante o período pós-operatório. Alguns trabalhos relataram que o uso concomitante de benzodiazepínicos não altera a incidência destas complicações 65,66 . Além disso, a ocorrência de pesadelos e sono agitado no pós-operatório foi a mesma entre as crianças que receberam cetamina, midazolam ou a associação dos dois fármacos 65 .…”