Hyperbaric vs. isobaric bupivacaine for spinal anaesthesia for elective caesarean section: a Cochrane systematic review

Abstract

Both isobaric and hyperbaric bupivacaine have been used for spinal anaesthesia for elective caesarean section, but it is not clear if one is better than the other. The primary objective of this systematic review was to determine the effectiveness and safety of hyperbaric bupivacaine compared with isobaric bupivacaine administered during spinal anaesthesia for elective caesarean section. We included 10 studies with 614 subjects in the analysis. There was no evidence of differences either in the risk of conversion to general anaesthesia, with a relative risk (95%CI) of 0.33 (0.09-1.17) (very low quality of evidence), or in the need for supplemental analgesia, the relative risk (95%CI) being 0.61 (0.26-1.41) (very low quality of evidence). There was also no evidence of a difference in the use of ephedrine, the amount of ephedrine used, nausea and vomiting, or headache. Hyperbaric bupivacaine took less time to reach a sensory block height of T4, with a mean difference (95%CI) of -1.06 min (-1.80 to -0.31). Due to the rarity of some outcomes, dose variability, use of adjuvant drugs and spinal technique used, future clinical trials should look into using adequate sample size to investigate the primary outcome of the need for supplemental analgesia.

The analgesic effects of intrathecal morphine in comparison with ultrasound‐guided transversus abdominis plane block after caesarean section: a randomised controlled trial at a Ugandan regional referral hospital

“…Anaesthetic capacity is extremely limited in Uganda, with currently approximately 70 physician anaesthetists and 430 non‐physician anaesthetists serving a population of almost 40 million . The field of anaesthesia encompasses not simply the delivery of intra‐operative anaesthesia but also pain control, critical care and improvement of peri‐operative safety . The use of ultrasound‐guided regional anaesthesia may both stimulate professional development, and allow anaesthetists to engage with their surgical and nursing colleagues to promote analgesia beyond the operating room.…”

International consensus statement on the management of hypotension with vasopressors during caesarean section under spinal anaesthesia

“…If no fentanyl is available, administer hyperbaric bupivacaine 10 mg alone. If no hyperbaric bupivacaine is available, an isobaric solution is acceptable , although there are concerns related to less reliable anaesthesia. It is also acceptable to mix dextrose with isobaric bupivacaine, to produce a hyperbaric solution; for example, mix 4 ml of 0.5% isobaric bupivacaine with 0.5 ml 50% dextrose to produce a solution of 0.44% bupivacaine with 5.55% dextrose.…”

Treatment of spinal anaesthesia-induced hypotension with cafedrine/theodrenaline versus ephedrine during caesarean section

“… 21 However, a recent systematic review showed no evidence for any differences in the use or dosing of ephedrine with hyperbaric or isobaric bupivacaine treatment groups. 22 Although more patients in the ephedrine arm received isobaric bupivacaine in this study, which could be seen to affect blood pressure values, SBP at diagnosis was comparable.…”