Is the use of automated mandatory boluses superior to basal infusion in maintaining epidural analgesia during labor?
TYPE OF REVIEW
A systematic review of 12 randomized controlled trials (RCTs), with a total of 1,121 participants.
RELEVANCE FOR NURSING
Epidural analgesia is commonly used in managing the pain experienced by women during labor. It involves injections of a local anesthetic into the epidural space, causing numbness in the lower part of the body.
There are two techniques used to maintain effective epidural analgesia during labor: automated mandatory boluses and basal infusion. Dosing is delivered intermittently with automated mandatory boluses and continually with basal infusion. Distribution of the medication is thought to be greater using automated mandatory boluses because of the higher pressure near the injection site, and this has been linked to more effective pain relief and reduced risk of motor blockade. This technique is employed in patient-controlled epidural analgesia, a method that allows patients to control the timing of bolus doses, and it has been associated with a number of positive outcomes, including a reduction in breakthrough pain requiring anesthetic intervention and increased patient satisfaction.
CHARACTERISTICS OF THE EVIDENCE
The primary objective of this review was to compare the use of automated mandatory boluses with basal infusion in the maintenance of epidural analgesia during labor. The primary outcomes included risk of breakthrough pain with the need for anesthetic intervention, risk of cesarean delivery, and risk of instrumental delivery. The secondary outcomes were duration of labor analgesia, local anesthetic consumption per hour, maternal satisfaction, and Apgar scores.
There were 12 RCTs included in this review, for a total of 1,121 participants. The authors reported a significant reduction in risk of breakthrough pain and local anesthetic consumption per hour with automated mandatory boluses compared with basal infusion, based on moderate-certainty evidence. There was little difference in risk of cesarean delivery with automated mandatory boluses compared with basal infusion (15% and 16%, respectively), based on low-certainty evidence. No difference was identified in the duration of labor analgesia (moderate-certainty evidence) or risk of instrumental delivery (low-certainty evidence) between the two techniques. An increase in maternal satisfaction was noted with automated mandatory boluses compared with basal infusion, and no differences were identified in Apgar scores.
BEST PRACTICE RECOMMENDATIONS
The authors concluded that while automated mandatory boluses are similar to basal infusion in maintaining epidural analgesia during labor, they may also decrease risk of breakthrough pain and improve maternal satisfaction while also decreasing the amount of local anesthetic needed. Pain management should allow for pain medication administration to be tailored to individual patients, as is the case with automated mandatory boluses, especially when patient-controlled epidural analgesia is used.
Future studies with a larger sample could improve the precision of these results. Future trials should investigate the duration of analgesia from epidural initiation to time of breakthrough pain. Patient-centric outcomes, such as maternal satisfaction or cost-effectiveness, could also be considered with advancement in new pump technology.
Sng BL, et al. Automated mandatory bolus versus basal infusion for maintenance of epidural analgesia in labour. Cochrane Database Syst Rev