It is thought to result from the inhalation of either fresh water or sea water resulting in lung damage and a ventilation-perfusion mismatch.
Near drowning can be divided into three stages:
- stage 1: acute laryngospasm that occurs after inhalation of a small amount of water
- stage 2: the victim still usually presents with laryngospasm but may begin to swallow water into the stomach
- 10-15% of patients still present with dry drowning caused by persistence of the associated laryngospasm
- in the remaining 85-90% of patients, the laryngospasm relaxes secondary to hypoxia and large amounts of water are aspirated
Features in stages 2 and 3 on chest radiographs are usually identical to pulmonary oedema from other non-cardiac causes 3.
- 1. Rumbak MJ. The etiology of pulmonary edema in fresh water near-drowning. Am J Emerg Med. 1996;14 (2): 176-9. doi:10.1016/S0735-6757(96)90128-X - Pubmed citation
- 2. Cohen DS, Matthay MA, Cogan MG et-al. Pulmonary edema associated with salt water near-drowning: new insights. Am. Rev. Respir. Dis. 1992;146 (3): 794-6. - Pubmed citation
- 3. Gluecker T, Capasso P, Schnyder P et-al. Clinical and radiologic features of pulmonary edema. Radiographics. 19 (6): 1507-31. Radiographics (citation) - Pubmed citation