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

postoperative vomiting (POV) (0.66, 0.37 –1.16; P¼0.16) or late POV (0.52, 0.25 –1.11; P¼0.09), but did reduce overall POV (0.48, 0.29– 0.79; P¼0.004). I.V. crystalloids did not reduce the risk of early PONV (0.74, 0.49– 1.12; P¼0.16), 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; P¼0.003). 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.