Swimming-induced pulmonary edema
|Swimming-induced pulmonary edema|
|Classification and external resources|
|Synonyms||Pulmonary oedema of immersion|
Swimming induced pulmonary edema (SIPE), also known as immersion pulmonary edema, occurs when fluids from the blood leak abnormally from the small vessels of the lung (pulmonary capillaries) into the airspaces (alveoli).
SIPE usually occurs during exertion in conditions of water immersion, such as swimming and diving. With the recent surge in popularity of triathlons and swimming in open water events there has been an increasing incidence of SIPE. It has been reported in scuba divers, apnea (breath hold) free-diving competitors combat swimmers, and triathletes. The causes are incompletely understood at the present time.
Signs and symptoms
- Shortness of breath out of proportion to effort being expended.
- Crackles, rattling or ‘junky’ feelings deep in the chest associated with breathing effort – usually progressively worsening with increasing shortness of breath and may be cause for a panic attack
- Cough, usually distressing and productive or not of a little pink, frothy or blood-tinged sputum (hemoptysis)
The wetsuit may feel as though it is hindering breathing ability
- high blood pressure
- long course length in the case of triathlon (half ironman or greater)
- female gender
- antiplatelet agents such as aspirin or fish oil
- Hydrostatic pressure from water immersion squeezes the extremities, and forces blood from the peripheral circulation (arms, legs) to the central circulation (heart, lungs, great vessels of the chest)
- Cold water may cause peripheral vasoconstriction and other neuro-humoral changes that contribute to central shift of the blood volume
- Wetsuits may add additional extrinsic compression to the extremities.
- Increased pressure somewhere in the pulmonary circulation (pulmonary artery hypertension, left heart diastolic dysfunction) leads to increased pressure gradient across the pulmonary capillaries
- Capillary stress from oxidative or physical injury leads to breach
- Management of hypertension is likely to be important for hypertensive athletes. ACE inhibitors (particularly angiotensin II receptor antagonists) may be effective antihypertensive medications in this setting given their effect on diastolic relaxation, but rationale is theoretical and evidence of SIPE-related benefit is anecdotal.
- Avoidance of excessive pre-swim hydration is advisable
- Nifedipine or sildenafil could theoretically be beneficial due to their ability to modify pulmonary artery pressure, but any use for SIPE is investigational and these agents are not approved for this use.
Management has generally been reported to be conservative, though deaths have been reported.
- Removal from water
- Diuretics and / or Oxygen when necessary
- Episodes are generally self-limiting in the absence of other medical problems 
Most of the medical literature on the topic comes from case series in military populations and divers, and an epidemiological study in triathletes. A recent experimental study showed increased pulmonary artery pressure with cold water immersion, but this was done in normal subjects rather than in people with a history of SIPE.
- Miller III, Charles C.; Calder-Becker, Katherine; Modave, Francois (2010). "Swimming-induced pulmonary edema in triathletes". The American Journal of Emergency Medicine 28 (8): 941–6. doi:10.1016/j.ajem.2009.08.004. PMID 20887912.[unreliable medical source?]
- Pons, M; Blickenstorfer, D; Oechslin, E; Hold, G; Greminger, P; Franzeck, UK; Russi, EW (1995). "Pulmonary oedema in healthy persons during scuba-diving and swimming". The European respiratory journal 8 (5): 762–7. PMID 7656948.[unreliable medical source?]
- Henckes, A; Lion, F; Cochard, G; Arvieux, J; Arvieux, C (2008). "L'œdème pulmonaire en plongée sous-marine autonome : fréquence et gravité à propos d'une série de 19 cas" [Pulmonary oedema in scuba-diving: frequency and seriousness about a series of 19 cases]. Annales Françaises d'Anesthésie et de Réanimation (in French) 27 (9): 694–9. doi:10.1016/j.annfar.2008.05.011. PMID 18674877.
- Liner, M. H.; Andersson, J. P. A. (2008). "Pulmonary edema after competitive breath-hold diving". Journal of Applied Physiology 104 (4): 986–90. doi:10.1152/japplphysiol.00641.2007. PMID 18218906.[unreliable medical source?]
- Koehle, Michael S; Lepawsky, Michael; McKenzie, Donald C (2005). "Pulmonary Oedema of Immersion". Sports Medicine (review) 35 (3): 183–90. doi:10.2165/00007256-200535030-00001. PMID 15730335.
- Yoder, JA; Viera, AJ (2004). "Management of swimming-induced pulmonary edema". American family physician 69 (5): 1046, 1048–9. PMID 15023003.
- Koehle, MS; Lepawsky, M; McKenzie, DC (2005). "Pulmonary oedema of immersion.". Sports medicine (Auckland, N.Z.) 35 (3): 183–90. PMID 15730335.
- Little, W (2001). "Hypertensive pulmonary oedema is due to diastolic dysfunction". European Heart Journal 22 (21): 1961–4. doi:10.1053/euhj.2001.2665. PMID 11603900.
- Almuntaser, Ibrahim; Mahmud, Azra; Brown, Angie; Murphy, Ross; King, Gerard; Crean, Peter; Feely, John (2009). "Blood Pressure Control Determines Improvement in Diastolic Dysfunction in Early Hypertension". American Journal of Hypertension 22 (11): 1227–31. doi:10.1038/ajh.2009.173. PMID 19763121.
- Wester, T. E.; Cherry, A. D.; Pollock, N. W.; Freiberger, J. J.; Natoli, M. J.; Schinazi, E. A.; Doar, P. O.; Boso, A. E.; Alford, E. L. (2008). "Effects of head and body cooling on hemodynamics during immersed prone exercise at 1 ATA". Journal of Applied Physiology 106 (2): 691–700. doi:10.1152/japplphysiol.91237.2008. PMID 19023017.
- Calder-Becker, Katherine. "Swimming Induced Pulmonary Edema (SIPE)". Endurance Triathletes.
- Radiology Kerley's B and C lines - Swimming Induced Pulmonary Edema - MedPix Medical Image Database