Pulmonary Function Changes During Diving: An Updated Narrative review and Implications for Fitness to Dive

Abstract

Pulmonary function during diving deserves attention because respiratory changes underwater may affect diver safety and the pre-dive medical evaluation. This narrative review examines the effects of diving on pulmonary function, focusing on the physiological basis, its impact on functional parameters, and its clinical relevance. We reviewed literature on diving physiology, pulmonary effects (short and long-term), respiratory complications, prevention, and fitness to dive. Pulmonary responses to diving result from increased ambient pressure, gas laws, immersion, intrathoracic hemodynamic shifts, and greater gas density. These factors influence ventilation, diffusing capacity, small airway function, and overall respiratory mechanics. In most acute exposures, functional changes are mild, temporary, and reversible. However, repeated exposure, especially in deep or saturation diving, may cause cumulative pulmonary effects; published results remain inconsistent. Diving-related pulmonary changes are clinically relevant because they may be linked to complications such as pulmonary barotrauma and immersion pulmonary edema. Understanding these physiological and clinical changes is important for prevention, respiratory screening, and medical fitness assessment for diving.