The incidence of clinically impactful postoperative nausea and vomiting after spinal anaesthesia for caesarean section in an academic hospital

Abstract

Background: Postoperative nausea and vomiting (PONV) are common side-effects following administration of spinal anaesthesia for
caesarean section (CS). PONV is reportedly perceived to be more distressing than pain by patients, which necessitates assessment of its
incidence to ensure that it is not undertreated and that effective measures are undertaken to address it.

Objectives: To study the incidence of PONV and associated factors in patients delivering via CS.

Methods: A total of 308 healthy parturients undergoing CS under spinal anaesthesia were recruited. This was a single-centre prospective  observational study conducted at an academic hospital. The institution standard of practice for spinal anaesthesia for CS was employed  and consisted of injecting 1.8 - 2.0 mL of hyperbaric bupivacaine 0.5% solution plus 10 µg fentanyl at the L3/L4 interspace after  preloading the patient with intravenous fluid 10 - 15 mL/kg. Phenylephrine boluses were used in managing any spinalinduced  hypotension according to standard protocol. The demographic data and patient characteristics were recorded. Complaints of PONV were  recorded postoperatively in the recovery room and 3 hours after the procedure. The clinical significance of PONV was assessed using the PONV impact scale.

Results: Of the 308 enrolled patients, 295 (95.8%) were black, 9 (2.9%) coloured and 4 (1.3%) white. The overall incidences of nausea and vomiting were 2.6% and 9.7%, respectively, with all episodes occurring during the first 3 hours after the procedure. The overall incidence of PONV was 10.1%. The odds of experiencing PONV for patients with increased birth weight, lowest blood pressure and Apfel score <3 were 1.0 (95% confidence interval (CI) 0.99 - 1.00), 1.01 (95% CI 0.98 - 1.04) and 0.35 (95% CI 0.11 - 1.12), respectively. There was no report  of clinically significant PONV.

Conclusion: The overall incidence of PONV in this study was 10.1%, and there was no clinically significant PONV.