Continuous infusion epidural analgesia in obstetrics

Abstract

SummaryThe effects of 0.08% (Group A ) and0.25% (Group B) Maintenance of epidural analgesia by continuous pump infusion of local anaesthetic into the epidural space has been shown to be effective and safe, and to offer advantages over intermittent top-up procedures. '.* The main advantages for the patient are uninterrupted analgesia and greater safety. For the anaesthetist there is less requirement for time consuming top-up injections.Concentrations selected for infusion epidurals have ranged from 0.0625% to 0.375%, at dose rates from 6.25 mg to over 20 mg/hour of bupivacaine.'-' Recently, it has been shown that a solution of bupivacaine a t a concentration of 0.08% infused at 25 ml/hour is able to provide long periods of uninterrupted analgesia in labour.6 Sixty per cent of the mothers required no supplementary top-ups. It was proposed that increasing the volume infused extended the liquid sleeve of local anaesthetic in the epidural space and caused more dermatomes to remain blocked.

Lumbar Epidural Analgesia for Labor and Vaginal Delivery

“…Studies comparing these two methods of drug administration show that continuous epidural infusions have the follow ing advantages: better analgesia [81,82], a more constant degree of analgesia [83], greater patient satisfaction [84], reduced frequencies of maternal hypotension [81], fetal bradycardia [81], and forceps delivery [85], and less time consumption for the anesthesiologist [86], Also, with con tinuous infusions of epidural analgesia, analgesia can be maintained with more dilute anesthetic solutions, and, thus, motor block is less intense. Tachyphylaxis to the anesthetic, which can occur if a block is allowed to wear off, is avoided by maintaining a continuous level of anal gesia.…”

Neurological Complications Following the Use of Continuous Extradural Analgesia With Bupivacaine

“…Bupivacaine is now used routinely for most extradural blocks because of its duration of action. Studies have shown in orthopaedic [6], obstetric [7] and general surgical patients that continuous infusions of extradural bupivacaine over prolonged periods, with concentrations of 0.0625-0.75 % have not resulted in toxic plasma concentrations. A study by Maier, Wawerski and Wulf [8] of 286 general surgical patients with…”

Comparison of Plasma Bupivacaine Concentrations During Continuous Extradural Infusion for Labour

“…Pain relief was not inferior with die weaker solution and the degree of sensory blockade was not remarkably different. Ewen and colleagues [5] have compared in detail the clinical BRITISH JOURNAL OF ANAESTHESIA effects of these two solutions and found fewer side effects with the weaker solution.…”

“…While the clinical effects of continuous extradural infusion are well documented [3][4][5], there have been no reports relating plasma concentration to clinical response. We report a comparison of plasma concentrations associated with the infusion of an 0.08 % and 0.25 % solution of bupivacaine given in the same dose per hour, and the clinical effects produced.…”