Epidural fentanyl and caesarean section: when should fentanyl be given?

Epidural fentanyl, adrenaline and clonidine as adjuvants to local anaesthetics for surgical analgesia: meta-analyses of analgesia and side-effects

BACKGROUND

The risk/benefit ratio of adding fentanyl, adrenaline and clonidine to epidural local anaesthetics for improving intraoperative analgesia is unclear. This meta-analysis was performed to clarify this issue.

METHODS

Trials retrieved by search were considered if they were prospective, controlled, epidural analgesia (without combining general anaesthesia) was planned and occurrence of pain during surgery or side-effects were reported. Papers entered meta-analysis if they reached a predefined minimum quality score. Pooled odds ratios (OR) and confidence intervals (CI) were computed. P < 0.05 was considered as significant.

RESULTS

Eighteen trials were included in the analysis for fentanyl. Fentanyl decreased the likelihood of pain (OR = 0.21, 95% CI = 0.15-0.30, P < 0.001) and increased the incidence of pruritus (OR = 5.59, 95% CI = 3.12-10.05, P < 0.001) and sedation (OR = 1.88, 95% CI = 1.19-2.98, P = 0.003), compared to control (local anaesthetic without fentanyl). Fentanyl had no effect on respiratory depression, nausea, vomiting and Apgar score. One case of respiratory depression of a newborn was observed. Because of the very low number of trials selected, evaluation of adrenaline and clonidine was not feasible.

CONCLUSION

The analysis of current literature shows that the addition of fentanyl to local anaesthetics for intraoperative epidural analgesia is safe and advantageous. The reduction in the incidence of pain during surgery is quantitatively high and therefore clinically significant. Side-effects are mild. Randomized, controlled trials have to be performed in order to clarify the role of adrenaline and clonidine as epidural adjuvants for surgical analgesia.

Anesthetic quality during cesarean section following subarachnoid or epidural administration of bupivacaine with or without fentanyl

BACKGROUND

It is often assumed that subarachnoid administration of local anesthetics produces a more profound blockade than epidural anesthesia. Furthermore, the addition of fentanyl has been reported to increase preferentially intraoperative analgesia. In the present study we set out to study these two issues in a randomized and controlled study with respect to perceived pain and discomfort during surgery and postoperative pain.

METHODS

In the present study, 100 parturients subjected to elective cesarean section, 34 nullipara and 66 multipara, received one out of four combinations of the local anesthetic bupivacaine and the opioid fentanyl; group A--bupivacaine 12.5 mg + 10 micrograms fentanyl subarachnoidally, group B--bupivacaine 12.5 mg + saline subarachnoidally, group C--bupivacaine 100 mg + 100 micrograms fentanyl epidurally, group D--bupivacaine 100 mg + saline epidurally; N = 25 in each group. Pain intensity and discomfort during surgery was assessed with a visual analogue scale (VAS). Postoperative pain intensity and need for analgesics postoperatively, ketobemidone, was registered for 24 h following surgery.

RESULTS

Intraoperative pain intensity and discomfort did not differ significantly between parturients in any of the four groups Postoperative pain was significantly more intense in parturients receiving local anesthetics subarachnoidally as compared to the epidural groups during the first 6-h period. This difference was also reflected in a significantly increased consumption of analgesics during this period. No significant differences between the groups were observed with regard to hemodynamics (blood pressure), respiration (oxygen saturation) or other effects such as nausea or itching. All neonates had normal Apgar and neonatal adaptive capacity scores (NACS).

CONCLUSION

We conclude that subarachnoidal (12.5 mg) and epidural (100 mg) injections with bupivacaine both produced adequate anesthetic quality in women undergoing elective cesarean section. The addition of fentanyl (10 micrograms subarachnoidally or 100 micrograms epidurally) did not significantly improve the quality of these already profound blockades.

Combined spinal epidural (CSE) analgesia: technique, management, and outcome of 300 mothers

Epidural analgesia in labour is commonly associated with some degree of lower limb weakness often severe enough to be described as paralysis by the mother. We aimed to produce rapid reliable analgesia with no motor block throughout labour. We report a pilot survey of 300 consecutive women requesting regional analgesia in labour who received a combined spinal epidural blockade (CSE). The initial dose was given into the subarachnoid space and analgesia maintained via an epidural catheter. A subarachnoid injection of 2.5 mg bupivacaine and 25 mug fentanyl was successfully given in 268 women (89.3%). Completely pain-free contractions within 3 min of this injection occurred in 195 women (65%) and in all 300 within 20 min and there was no associated motor block in 291 (97%). 141 women chose to stand, walk or sit in a rocking chair at some time during labour. Only 38 women (12.6%) were immobile during the first stage of labour. Analgesia was maintained via the epidural catheter with bolus doses of 10-15 ml of 0.1% bupivacaine and 0.0002% fentanyl. The mean bupivacaine requirement was 9.5 mg/h throughout the entire duration of analgesia. The incidence of post lumbar puncture headache was 2.3%. Transient hypotension occurred in 24 women (8%) and was treated with 6 mg intravenous boluses of ephedrine. Complete satisfaction with analgesia and mobility was reported 12-24 h post partum by 95% of mothers. The use of this analgesic technique caused no alteration in obstetric management or post partum care of the women.