Impact of Obesity on Propofol Dosing: Implications for Anesthetic Outcomes.

Obesity presents significant challenges in anesthetic management because physiologic and body composition changes can substantially alter drug pharmacokinetics (PK) and pharmacodynamics (PD). Propofol is one of the most commonly used intravenous anesthetic agents for procedural sedation and general anesthesia; however, optimal dosing strategies in patients with obesity remain controversial. Conventional dosing based on total body weight (TBW) may increase the risk of adverse events, whereas alternative weight scalars and model-informed approaches have been proposed. This systematic review aimed to evaluate the impact of obesity on propofol dosing and propofol-associated anesthetic outcomes, with particular emphasis on hypnotic adequacy, hemodynamic stability, respiratory safety, recovery characteristics, and PK/PD considerations. This systematic review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines. A comprehensive literature search was performed using PubMed, BioMed Central, and ClinicalTrials.gov. Eligible studies included randomized controlled trials, prospective and retrospective observational studies, and PK/PD investigations evaluating propofol administration in adults with obesity. Primary outcomes were hypnotic adequacy and hemodynamic stability. Secondary outcomes included respiratory and airway events, recovery characteristics, and PK/PD parameters. Risk of bias was assessed using the Joanna Briggs Institute Critical Appraisal Tools. Owing to substantial heterogeneity in study design, patient populations, dosing strategies, and outcome reporting, findings were synthesized using a structured narrative approach. Sixteen studies met the eligibility criteria and were included in the qualitative synthesis. The included studies demonstrated that obesity significantly influences propofol pharmacology and clinical response. Across studies, TBW-based dosing was frequently associated with greater hemodynamic depression, including hypotension and bradycardia, without consistently improving hypnotic adequacy. Respiratory and airway complications, particularly hypoxemia and the need for airway interventions, occurred more frequently in patients with higher body mass indexes during procedural sedation. PK/PD investigations consistently reported alterations in volume of distribution, clearance, and concentration-effect relationships in obese patients, supporting the use of lean body weight-based or model-informed dosing approaches. Recovery outcomes were less frequently reported, but when reported, generally indicated improved recovery profiles with reduced propofol requirements through individualized dosing strategies or adjunctive agents. Current evidence indicates that obesity substantially alters propofol's PK, PD, and clinical anesthetic outcomes. TBW-based dosing may increase the risk of hemodynamic and respiratory adverse events without reliably improving anesthetic effectiveness. The available evidence supports considering alternative weight-scaling factors, individualized dose titration, and physiologic monitoring to optimize propofol administration in adults with obesity. Further prospective studies are needed to establish standardized dosing strategies and validate clinically applicable model-informed approaches.