Comparison of Two Methods of Administration of the Epidural, by Programmed Intermittent Bolus or Continuous Perfusion, on the Incidence of Cesarean Sections and Instrumented Deliveries in Primiparous Women

Summary

The epidural has been recognized for many years as the most effective analgesia method for obstetrical labor. Several different administration protocols have been evaluated over the years with the aim of reducing side effects. Epidurals have been incriminated in the increase of instrumented births. It is indeed possible that the motor block induced by the epidural reduces the pelvic tonus and the ability of the mother to push during the second stage of the labor. Furthermore, this motor block might lead to a ill rotation of the foetal head within the pelvis, which could lead to instrumentation (suction cups, forceps). In the investigator's institution, an ongoing study also provided interim that showed that the use of a low concentration of local anesthetics (as opposed to a higher concentration) tends to decrease the instrumentation and cesarean sections rate in the institution's population.However, the optimal administration mode of the local anesthetic in the epidural remains unknown. In the last few years, there has been a growing interest for a new method of administration of the solution within the epidural, by programmed intermittent bolus. This method allows a better distribution of the local anesthetics in the epidural space, compared to a continuous perfusion. This study therefore focuses on the relationship between the use of epidural with programmed intermittent boluses and the rate of instrumented deliveries and cesarean sections. The exact mode of administration of boluses is also subject to discussion in the literature. One can question whether it is preferable to administer smaller boluses more frequently or larger less frequent boluses. A few studies have investigated this issue and recommend to administer larger and more spaced bolus (10 mL to 60 minutes).This better matches the sought after physiology (ie a wider distribution in the epidural space) and provides equivalent analgesia to smaller, more frequent boluses.

Timeline

Start

2016-03-08

Primary completion

2018-03-20

Completion

2018-03-20

Publications

• Background Howell CJ. Epidural versus non-epidural analgesia for pain relief in labour. Cochrane Database Syst Rev. 2000;(2):CD000331. doi: 10.1002/14651858.CD000331.
• Background George RB, Allen TK, Habib AS. Intermittent epidural bolus compared with continuous epidural infusions for labor analgesia: a systematic review and meta-analysis. Anesth Analg. 2013 Jan;116(1):133-44. doi: 10.1213/ANE.0b013e3182713b26. Epub 2012 Dec 7.
• Background Thorp JA, Hu DH, Albin RM, McNitt J, Meyer BA, Cohen GR, Yeast JD. The effect of intrapartum epidural analgesia on nulliparous labor: a randomized, controlled, prospective trial. Am J Obstet Gynecol. 1993 Oct;169(4):851-8. doi: 10.1016/0002-9378(93)90015-b.
• Background Comparative Obstetric Mobile Epidural Trial (COMET) Study Group UK. Effect of low-dose mobile versus traditional epidural techniques on mode of delivery: a randomised controlled trial. Lancet. 2001 Jul 7;358(9275):19-23. doi: 10.1016/S0140-6736(00)05251-X.
• Background Kaynar AM, Shankar KB. Epidural infusion: continuous or bolus? Anesth Analg. 1999 Aug;89(2):534. doi: 10.1097/00000539-199908000-00063. No abstract available.
• Background Wong CA, Ratliff JT, Sullivan JT, Scavone BM, Toledo P, McCarthy RJ. A randomized comparison of programmed intermittent epidural bolus with continuous epidural infusion for labor analgesia. Anesth Analg. 2006 Mar;102(3):904-9. doi: 10.1213/01.ane.0000197778.57615.1a.
• Background Sia AT, Leo S, Ocampo CE. A randomised comparison of variable-frequency automated mandatory boluses with a basal infusion for patient-controlled epidural analgesia during labour and delivery. Anaesthesia. 2013 Mar;68(3):267-75. doi: 10.1111/anae.12093. Epub 2012 Dec 20.
• Background Lim Y, Chakravarty S, Ocampo CE, Sia AT. Comparison of automated intermittent low volume bolus with continuous infusion for labour epidural analgesia. Anaesth Intensive Care. 2010 Sep;38(5):894-9. doi: 10.1177/0310057X1003800514.
• Background Wong CA, McCarthy RJ, Hewlett B. The effect of manipulation of the programmed intermittent bolus time interval and injection volume on total drug use for labor epidural analgesia: a randomized controlled trial. Anesth Analg. 2011 Apr;112(4):904-11. doi: 10.1213/ANE.0b013e31820e7c2f.
• Background Breen TW, Shapiro T, Glass B, Foster-Payne D, Oriol NE. Epidural anesthesia for labor in an ambulatory patient. Anesth Analg. 1993 Nov;77(5):919-24. doi: 10.1213/00000539-199311000-00008.

Drugs

Indications

No indication recorded.