THE ASSOCIATION BETWEEN THE OCULOCARDIAC REFLEX AND POSTOPERATIVE VOMITING IN CHILDREN UNDERGOING STRABISMUS SURGERY

The oculocardiac reflex (OCR) is a potentially serious complication of ophthalmic surgery which is most commonly elicited during paediatric strabismus surgery. Post-operative vomiting (POV) is also extremely co mmon after such procedures and may result in admission following plann ed day-case surgery. Although many factors play a part in the occurren ce of POV, stimulation of the trigemino-vagal reflex are is thought to explain the particularly high rate of vomiting after strabismus surge ry. The OCR and the vaso-vagal response share this neuronal pathway, t he bradycardia of the OCR often being the only objective feature of th e vaso-vagal response while the patient is anaesthetised. The aim of t his study was to investigate the possible association between the occu rrence of the OCR and subsequent POV in children undergoing strabismus surgery. We have studied this relationship in 79 children, aged betwe en 1 and 13 years, undergoing strabismus surgery under standardised an aesthetic conditions. A positive OCR was regarded as a drop in heart r ate of 10% or more, or the onset of a dysrhythmia. An intraoperative O CR was elicited in 51 (64.6%) of the 79 children, whilst 29 (36.7%) de veloped POV in the subsequent 24 h period. There was a significant ass ociation between a positive intraoperative OCR and POV (p = 0.01): chi ldren with a positive OCR were 2.6 times more likely to vomit than tho se without the reflex. We conclude that there is an association betwee n the occurrence of the OCR and POV and discuss possible preventive st rategies.