EVALUATION OF ORAL KETAMINE FOR PAIN RELIEF DURING NORMAL LABOUR AT EBONYI STATE UNIVERSITY TEACHING HOSPITAL, ABAKALIKI

Abstract

INTRODUCTION: The hallmark of good obstetric practice both in developed and developing countries is a good labour analgesia; which is easily administered, affordable, accessible, acceptable, efficient, effective and noninvasive .
This prospective single blind randomized study was to evaluate if a subanaesthetic dose of oral ketamine can provide adequate pain relief to parturients in active phase of labour. Furthermore, to determine the minimum effective dose of oral ketamine administered to parturients in established first stage of labour that will produce clinically adequate analgesia and allow the parturient cooperate fully with her assistants during delivery; to determine the effect (if any) on the newborn using Apgar score parameters and to determine adequacy of analgesia so provided for suturing episiotomy and vaginal laceration.
METHODS: The study was conducted at the Ebonyi State University Teaching Hospital, Abakaliki over a period of one year; from January 2008 – December 2008. Two hundred and seventy three (273) women randomly received 3 different doses of oral ketamine (A=4mgkg-1, B=5mgkg-1 and C=6mgkg-1) as a single dose from the time the patient was in active phase of labour (cervical dilatation=4cm or more). One hundred and eleven (111) women who received oral ketamine in labour had episiotomy and vaginal laceration repair without additional analgesia.
RESULTS: Patients in the three groups had labour analgesia; however, 4mgkg1provided analgesia 96.4% efficacy with lowest adverse/side effects for labour and episiotomy/vaginal laceration repair, 5mgkg-1 oral ketamine provided 100% efficacy and 6mgkg-1 oral ketamine provided 100% efficacy. However, it was noticed that there was increased adverse/ side effects of ketamine. Dizziness,hallucination, nausea and vomiting were statistically significant while nystagmus,sedation and hypersalivation were not statistically significant. Babies delivered by women that received 4mgkg-1 and

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5mgkg-1 oral ketamine had no birth asphyxia. However, there was a 2 fold relative risk of birth asphyxia in babies whose mothers received 6mgkg-1 ketamine.
CONCLUSION: This study has shown that oral ketamine at subanaesthetic doses (4mgkg-1, 5mgkg-1 and 6mgkg-1) provided good analgesia for women in labour. It was feasible for the repair of episiotomy and perineal laceration. The quality of analgesia was associated with high rate of side effects. However, the 4mgkg-1 dose appears to provide effective analgesia with tolerable side effects. Thus oral ketamine at a dose of 4mgkg-1could be offered to women who desire labour analgesia.