Supplemental intravenous crystalloids for the prevention of postoperative nausea and vomiting: quantitative review

Abstract

Hypovolaemia after overnight fasting is believed to exacerbate postoperative nausea and vomiting (PONV). However, data on the efficacy of supplemental i.v. crystalloids for PONV prophylaxis are conflicting. We performed a literature search using CENTRAL, MEDLINE, EMBASE, CINAHL, and Web of Science. We included prospective randomized controlled trials that reported PONV event rates in patients receiving supplemental i.v. crystalloids or a conservative fluid regimen after elective surgery under general anaesthesia. Studies were evaluated with regard to random sequence generation, allocation concealment, blinding of participants, personnel, and outcome assessment, incomplete outcome data, and selective reporting. We identified 15 trials (n=787 crystalloids; n=783 conservative fluids). Compared with conservative fluids, i.v. crystalloids reduced the risk of early postoperative nausea (PON) (relative risk 0.73, 95% confidence interval 0.59-0.89; P=0.003), late PON (0.41, 0.22-0.76; P=0.004), and overall PON (0.66, 0.46-0.95; P=0.02). I.V. crystalloids did not reduce the risk of early postoperative vomiting (POV) (0.66, 0.37-1.16; P=0.16) or late POV (0.52, 0.25-1.11; P=0.09), but did reduce overall POV (0.48, 0.29-0.79; P=0.004). I.V. crystalloids did not reduce the risk of early PONV (0.74, 0.49-1.12; P=0.16), but did reduce the risk of late PONV (0.27, 0.13-0.54; P<0.001) and overall PONV (0.59, 0.42-0.84; P=0.003). I.V. crystalloids reduced the need for antiemetic rescue treatment (0.56, 0.45-0.68; P<0.001). In summary, supplemental i.v. crystalloids were associated with a lower incidence of several PONV outcomes. However, a number of PONV outcomes failed to reach statistical significance, perhaps due to the lack of power. Thus, studies sufficiently powered for the less frequent outcomes (e.g. POV) are required.

Adverse effects of crystalloid and colloid fluids

“…Blood is directed away from the gastrointestinal tract, which is an early trouble-spot for ischemia. A review by Apfel et al [5] showed that the administration of as little as 2 mL kg -1 h -1 of crystalloid fluid during surgery was associated with a higher incidence of nausea, which may be due to this type of re-distribution. An additional infusion of crystalloid fluid alleviated the problem, thereby supporting local hypovolemia as the cause.…”

Effect of Intra-Operative Intravenous Crystalloid Infusion on PostOperative Nausea and Vomiting after Diagnostic Gynaecological Laparoscopy- Comparison of 30 mL/Kg & 15 mL/Kg

“…9 Among Non-pharmacological methods, besides transcutaneous acupoint electrical stimulation (TAES), acupuncture and acupressure, peri-operative liberal intravenous fluid administration has been shown to reduce PONV. 9,10,11 This study is designed to evaluate the effect of intraoperative intravenous crystalloid infusion at two different doses (30 mL/Kg and 15 mL/Kg) on the incidence of PONV, on patients undergoing diagnostic gynaecological laparoscopic surgery.…”

Evidence-based out-of-hours hospital medicine

“…However, within this particular patient group, generalisability is limited. A quantitative review of low-powered studies found that supplemental intravenous crystalloids were associated with reduced incidence of several postoperative nausea and vomiting (PONV) outcomes 41. Negating hypovolaemia from overnight fasting by administering overnight intravenous fluid infusion may be supposed to improve PONV outcomes.…”