Effect of different anesthetic agents on oculocardiac reflex in pediatric strabismus surgery.
OBJECTIVE
The oculocardiac reflex (OCR) occurs frequently during pediatric strabismus surgery. The aim of this study was to assess the effects of various anesthetic regimens on the incidence of OCR during the surgery.


METHODS
Two hundred and eighty children, 1 to 9 years old, undergoing elective strabismus surgery, were randomly assigned to eight groups; ketamine-sevoflurane (KS), ketamine-desflurane (KD), ketamine-propofol (KP), ketamine-remifentanil (KR), midazolam-sevoflurane (MS), midazolam-desflurane (MD), midazolam-propofol (MP), and midazolam-remifentanil (MR). No premedication was given. Anesthesia was induced using ketamine 1 mg kg(-1) or midazolam 0.15 mg kg(-1) with 66% N(2)O in O(2). Laryngeal mask airways (LMAs) were placed with rocuronium 0.5 mg kg(-1). Anesthesia was maintained with sevoflurane 2-3 vol. %, desflurane 5-6 vol. %, propofol 7-8 mg kg(-1) h(-1), or remifentanil 0.75 microg kg(-1) over 1 min, followed by a continuous infusion of remifentanil 0.5 microg kg(-1) min(-1) with 66% N(2)O in O(2). Heart rate (HR) was recorded during extraocular muscle (EOM) manipulation. OCR was defined as a reduction in HR of more than 20% induced by the traction of an EOM.


RESULTS
In patients given ketamine, OCR occurred more frequently in the KP (65.7%) and KR (62.9%) groups than in the KD (29.4%) and KS (37.1%) groups (P < 0.05). In patients given midazolam, OCR occurred more frequently in the MP (54.3%) and MR (60.6%) groups than in the MD (36.4%) and MS (31.4%) groups (P < 0.05).


CONCLUSIONS
Propofol or remifentanil anesthesia was associated with a higher incidence of OCR during pediatric strabismus surgery than sevoflurane and desflurane anesthesia, when either ketamine or midazolam was used as an induction agent.
Choi
So Ron
SR
Department of Anesthesiology and Pain Medicine, Dong-A University Hospital, Seo-gu, Busan, Korea.
Park
Sang Won
SW
Lee
Jong Hwan
JH
Lee
Seung Cheol
SC
Chung
Chan Jong
CJ
D000732:Androstanols; D000758:Anesthesia; D000768:Anesthesia, General / Q000009:adverse effects*; D000777:Anesthetics / Q000009:adverse effects*; D000778:Anesthetics, Dissociative; D018685:Anesthetics, Inhalation; D018686:Anesthetics, Intravenous; D002648:Child; D002675:Child, Preschool; D000077335:Desflurane; D005260:Female; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D007223:Infant; D007431:Intraoperative Complications / Q000139:chemically induced* / Q000453:epidemiology / Q000503:physiopathology*; D007530:Isoflurane / Q000031:analogs & derivatives; D007649:Ketamine; D008297:Male; D008738:Methyl Ethers; D008874:Midazolam; D016343:Monitoring, Intraoperative; D019148:Neuromuscular Blockade; D003473:Neuromuscular Nondepolarizing Agents; D013508:Ophthalmologic Surgical Procedures; D012024:Reflex, Oculocardiac / Q000187:drug effects*; D000077123:Rocuronium; D000077149:Sevoflurane; D013285:Strabismus / Q000601:surgery*
D000732:Androstanols; D000777:Anesthetics; D000778:Anesthetics, Dissociative; D018685:Anesthetics, Inhalation; D018686:Anesthetics, Intravenous; D008738:Methyl Ethers; D003473:Neuromuscular Nondepolarizing Agents; D000077149:Sevoflurane; D007649:Ketamine; D000077335:Desflurane; D007530:Isoflurane; D008874:Midazolam; D000077123:Rocuronium