Immersion pulmonary edema (IPE) is a rare but important complication associated with surface swimming and underwater diving. It tends to reoccur and can be fatal. It is not very well-known to clinicians involved in the care of individuals participating in aquatic activities. We performed a systematic review of immersion pulmonary edema to describe the condition and provide guidelines for its management.

We searched PubMed to identify case reports and studies using the MeSH terms "immersion," "pulmonary edema," "cold-induced," "exercise," "hemodynamics," "water immersion,'' "cardiovascular response," alone and in combinations. We identified 121 relevant articles including 54 case reports. We reviewed in detail 24 studies and all 54 case reports.

The incidence of IPE is estimated to be around 1.1- 1.8%. The risk factors for IPE include age >50 years, female sex, overhydration before exercise, tight wetsuits, cold water exposure and physically trained individuals such as endurance athletes. Individuals with pre-existing heart disease are at increased risk, however, IPE is seen even in healthy individuals. Symptoms such as cough, sputum production, hemoptysis and shortness of breath can occur immediately after immersion. Combination of water immersion, cold exposure, and exercise lead to an increase in pulmonary capillary pressures and eventual pulmonary capillary stress failure that leads to the flooding of alveolar spaces and edema. Conclusion and relevance: Clinicians should be aware of IPE to avoid overestimating the severity of coronary or valvular conditions sometimes coincidentally present in IPE victims. Management is usually supportive. Functional and clinical recovery usually happens spontaneously within 24 h to 2 days, with or without diuretic therapy and a beta-adrenergic agonist. IPE can be recurrent and fatal, hence subjects with a history of IPE should undergo extensive cardiopulmonary investigation and should avoid cold water and physically demanding swimming events or avoid immersion activities.