Keane 1986.

Methods	Design: prospective randomized controlled trial Country: Ireland Multisite: no International: no Treatment duration: intraoperative period Follow‐up: 6 hours postoperatively Operative procedure(s): breast biopsy, varicose vein ligation, dilatation and curettage, and inguinal hernia repair Randomization unit: participants Analysis unit: individual
Participants	212 participants enrolled ASA I to II participants aged 18 to 50 years old undergoing minor surgical procedures that included breast biopsies, varicose vein ligations, dilatation and curettage, and inguinal hernia repairs No exclusion criteria were provided. Randomized to: fluid group (n = 108, 51%); no fluid group (n = 104, 49%). All patients completed the first questionnaire (6 hours postoperatively), which evaluated PONV. 36 (17%) and 28 (24%) of eligible patients did not complete the second and third questionnaires, respectively. These questionnaires did not evaluate PONV. Main characteristics of participants: age range of participants 18 to 50 years; analysis of age by group was not stated; sex of enrolled participants not provided.
Interventions	Fluid group (intervention): intraoperative bolus of 1 litre of Ringer's lactate and postoperative bolus of 1 litre 5% dextrose in water No fluid group (control): no perioperative fluid Co‐interventions: none stated
Outcomes	Nausea and vomiting were assessed as dichotomous outcomes using a questionnaire administered 6 hours postoperatively. Questionnaires also documented thirst, dizziness, drowsiness, and headache at 6 hours. Measurements of serum osmolalities were taken in the immediate postoperative period. Postoperative well‐being was assessed (in comparison to preoperative status) by questionnaire on the 3rd postoperative day. Participants who had received a previous anaesthetic were asked to compare their study anaesthetic experience to their previous anaesthesia experience(s) by questionnaire at 1 month postoperatively.
Notes	Trial registration: not stated Funder: not stated A priori sample size estimation: not stated Conducted: dates not stated Declared conflicts of interest: not stated
Risk of bias
Bias	Authors' judgement	Support for judgement
Random sequence generation (selection bias)	Unclear risk	Participants were randomly allocated, but no information on the randomization process was provided.
Allocation concealment (selection bias)	Unclear risk	Participants were randomly allocated, but no information on the randomization process was provided.
Blinding of participants and personnel (performance bias) All outcomes	Unclear risk	The blinding process of personnel was not described. Participants were aware of their allocation status but not the purpose of the IV fluid.
Blinding of outcome assessment (detection bias) All outcomes	Unclear risk	Blinding of outcome assessors completing questionnaires was not described.
Incomplete outcome data (attrition bias) All outcomes	Low risk	83% of participants responded to the second questionnaire. 76% of participants responded to the 3rd questionnaire. Neither of these questionnaires examined PONV outcomes.
Selective reporting (reporting bias)	High risk	Vomiting data were not reported.
Other bias	Low risk	There were no other sources of bias.