Background/Objectives: Hypo-hydration is a major health concern that affects performance and is associated with increasing morbidity and growing health care costs. There is an emerging interest in optimizing hydration and identifying how factors such as ingestion rate and beverage composition affect hydration. This study examined three beverages with varying ingestion rates and measured markers of hydration. Methods: Thirty healthy, active participants between the ages of 18 and 45 years were given three different beverages on three separate days. The beverages were of identical volumes (1 L), but differed in the rate of ingestion, carbohydrate content and electrolyte content. Beverage 1 and water alone were both consumed at a metered rate of one liter over four hours, whereas Beverage 2 was used as a positive control and was consumed at a bolus rate of one liter in 30 min. Results: After six hours, Beverage 1 significantly improved markers of hydration compared to water alone or Beverage 2. Beverage 1 decreased cumulative urine output vs. water alone by 32% (absolute difference −0.33 L; CI ± −0.16 to −0.51) and vs. Beverage 2 by 26% (absolute difference −0.26 L; CI ± −0.13 to −0.38). Beverage 1 increased the beverage hydration index vs. water alone by 64% (absolute difference +0.64 L; CI ± 0.36 to 0.92) and vs. Beverage 2 by 48% (absolute difference +0.53 L; CI ± 0.30 to 0.76). Conclusions: Beverage 1 is superior to water alone at improving hydration when it is ingested at similar rates. Moreover, metered ingestion of Beverage 1 improved hydration compared to a bolus ingestion of Beverage 2, this could be due to the dissimilar ingestion rates and/or beverage composition.
Background/Objectives: Opioid-free anesthesia (OFA) has emerged as a potential alternative to opioid-based anesthesia (OBA) to reduce opioid-related adverse effects. This meta-analysis compares OFA and OBA with respect to postoperative pain and opioid consumption. Methods: PubMed, Cochrane, and Embase libraries were searched for OFA studies published through 12 June 2025. Randomized controlled trials (RCTs) conducted on adult humans were selected; observational studies, studies including neuraxial anesthesia, and RCTs currently awaiting approval were excluded. A forest plot was used to summarize findings of a random-effects meta-analysis to compare OFA (treatment) and OBA (control). Results: Of 1446 citations found, twenty-nine articles met our inclusion criteria. Twenty-six studies reported pain scores with a 0–10 scale. OFA was associated with lower postoperative pain scores (Hedges’ g = –0.34; 95% CI –0.55 to –0.13; p < 0.001; I2 = 84%) but with high heterogeneity, limiting clinical significance or strong interpretation of results. Eleven trials were analyzed for opioid use, showing a small reduction with OFA (Hedges’ g = –0.55; 95% CI –1.10 to –0.005; p = 0.048; I2 = 96.22%). Subgroup outcomes favored OFA, with an overall reduction in pain found specifically in endoscopic abdominal surgeries. Some secondary outcomes also indicated potential improved recovery profiles through OFA for certain surgeries. Conclusions: OFA was associated with statistically significant lower postoperative pain scores, along with opioid consumption, but with a small effect size and high heterogeneity when compared to OBA. This is potentially comparable in pain control and opioid consumption with limited clinical significance. Overall, outcomes support the continued controlled study of OFA as an alternative to conventional analgesia.