Immersion Pulmonary Edema
- Swimming-Induced Pulmonary Edema (SIPE)
- Immersion Pulmonary Edema (IPE)
- This page refers to Immersion Pulmonary Edema (IPE), a phenomenon where pulmonary edema in swimmers and divers without an aspiration event.
- First reported in scuba divers in 1981
- Estimated to be about 1.8% to 5% in experienced combat swimmers
- In one study of open sea swimmers, 1.8% of young healthy men developed IPE (need citation)
- In a survey of 1250 divers, 1.1% of respondents had symptoms consistent with IPE
- In a survey of USA triathlon participants, 1.4% of respondents recounted symptoms consistent with IPE
- More than 20 cases are reported annually among US Navy combat swimmers
- Overall, not well described in the literature
- Presents with symptoms similar to pulmonary edema: cough, dyspnea, hemoptysis, without a history of aspiration
- Similar to exertion-related pulmonary edema see in racehorses
- Can occur in individuals without having pre-existing cardiac conditions
- Proposed mechanism
- Stress failure of pulmonary capillaries due to redistribution of circulating fluid in central circulation
- Increased pulmonary vasculature blood volume from water immersion, cold exposure and exercise
- Reversible myocardial dysfunction may also play a role
- Increases cardiac output
- Doubles pulmonary artery pressure
- Blood is also redistributed from extremities to the thorax
- Continuous negative airway pressure (breathing)
- Immersed person breathes with continuous negative airway pressure equal to the vertical distance between the water surface and the lung centroid
- Raised pulmonary capillary pressures and negative airway pressures set the stage for fluid transudation into the alveoli
- However, usually additional factors are required to precipitate frank pulmonary edema.
- Warm water immersion
- Hydrostatic effects of water compression immediately pushes as much as 700 mL of blood centrally
- Increases cardiac output, heart size, cardiac filling pressures
- Cold water
- Leads to vasoconstriction, increases pulmonary capillary pressure
- Scuba diving
- Ambient hydrostatic pressure increases at depth (e.g. 30 m of seawater, pressure is 4 bar)
- This is less than the inspired O2 from the open circuit scuba system, leading to vasoconstriction
- During ascent, head is above lung centroid with continuous negative airway pressure which can worsen IPE
- Most patients with IPE are otherwise healthy
- In one survey of patients, only 24% had an identifiable cardiopulmonary risk factor
- Swimming/ water factors
- Military/ Combat swimmers (e.g. Navy Seals)
Differential Diagnosis Dive Medicine
- Barotrauma of descent
- At depth injuries
- Oxygen Toxicity: harmful effects of breathing oxygen at higher partial pressures than normal
- Nitrogen Narcosis: toxic effects of breathing nitrogen-containing gases while at depth
- Hypothermia: decrease core temperature with prolonged exposure to cold water
- Carbon Monoxide Toxicity: CO toxicity typically results from a faulty air compressor
- Caustic Cocktail: Inhalation of absorbent material used to scrub CO2 mixes with water
- Barotrauma of ascent
- Patients will not have a history of aspiration or laryngospasm
- Onset is within 10 to 30 minutes of immersion
- 90% have Cough, dyspnea and/or sputum production after cold water immersion
- Hemoptysis (50%)
- Labored breathing
- Frothy sputum
- Chest discomfort
- Loss of consciousness
- Physical Exam
- Hypoxia may be present (SpO2 < 92%)
- Rales or ronchi may be heard
- Heart sounds may include S3 or mitral rergutation
- Bilateral inspiratory crackles
- Standard Chest Radiograph
- Often normal within 12-18 hours of the event
- Findings include interstitial pulmonary edema, alveolar filling process
- Also seen are cephalization, kerley B lines, ground glass opacities, infiltrates
- More sensitive than chest radiograph
- However not needed to make diagnosis
- Pleural effusion
- Ground glass opacities
- ST segment changes
- Global or segmental hypokinesia
- Reduced LV EF
Pulmonary Function Testing
- Findings consistent with restrictive changes
- Arterial Blood gas
- If obtained, ABG may reveal A-a gradient > 30
- Cardiac biomarkers
- May be elevated
- Other labs which may be elevated
- Brain natriuretic peptide (BNP)
- Ischemia-modified albumin
- Currently, there is no accepted classification system
- Management is primarily supportive care
- Remove from water
- Remove cold clothing, place in warm environment
- Remove wet suit if present
- Consider Albuterol
- Supplemental oxygen
- Keep SpO2 > 92%
- More severe cases may require invasive ventilation, hemodynamic support
- Typically self limited, lasts 24-48 hours
- Shown to decrease Mean Pulmonary Arterial Pressure (MPAP) and Pulmonary Artery Wedge Pressure (PAWP)
- May prevent progression of pulmonary edema
- Dosing is uncertain
- Used to prevent recurrence
- No data to support at this time
- Prevention is key
- Treat underlying conditions (i.e. LV dysfunction, hypertension)
- Swim in tepid water
- Avoid tight wet suits, hyperhydration
- May help prevent IPE in some athletes
- May also affect performance in other activities such as biking and running in triathlons
- Cardiopulmonary risk factors
- Testing/ screening should be performed in patients with risk factors
- If present, avoid long swimming sessions
Rehab and Return to Play
- No clear guidelines
Return to Play/ Work
- Self limited condition typically resolves in 24 to 48 hours
- Athletes should be seen by a physician prior to returning to swimming or diving
Complications and Prognosis
- Wilmshurst PT, Nuri M, Crowther A, et al. Cold-induced pulmonary edema in scuba divers and swimmers and subsequent development of hypertension. Lancet. 1989;1(8629):62–65.
- Volk, Charles, et al. "Incidence and impact of swimming-induced pulmonary edema on Navy SEAL candidates." Chest 159.5 (2021): 1934-1941.
- Pons M, Blickenstorfer D, Oechslin E, et al. Pulmonary edema in healthy persons during scuba diving and swimming. Eur Respir J. 1995;8:762–767.
- Miller CC III, Calder-Becker K, Modave F. Swimming-induced pulmonary edema in triathletes. The American Journal of Emergency Medicine. 2010;28(8):941–946.
- Mahon RT, Kerr S, Amundson D, et al. Immersion pulmonary edema in special forces combat swimmers. Chest. 2002;122:383–384.
- Arborelius, M., et al. "Hemodynamic changes in man during immersion with the head above water." (1972).
- Carter EA, Koehle MS. Immersion pulmonary edema in Female Triathletes. Pulmonary Medicine. 2011;2011:1–4.
- Hampson NB, Dunford RG. Pulmonary edema of scuba divers. Undersea Hyperbaric Med. 1997;24(1):29–33.
- Ludwig BB, Mahon RT, Schwartzman EL. Cardiopulmonary function after recovery from swimming-induced pulmonary edema. Clin J Sport Med. 2006 Jul;16(4):348-51.
- Boussuges A, Pinet C, Thomas P, et al. Haemoptysis after breathhold diving. European Respiratory Journal. 1999;13(3):697–699.
- Yoder JA, Viera AJ. Management of swimming-induced pulmonary edema. Am Fam Physician. 2004 Mar 1;69(5):1046, 1048-9.
- Weiler-Ravell, D., et al. "Pulmonary oedema and haemoptysis induced by strenuous swimming." Bmj 311.7001 (1995): 361-362.
- Casey H, Dastidar AG, MacIver D. Swimming-induced pulmonary edema in two triathletes: a novel pathophysiological explanation. J R Soc Med. 2014;107:450–452.
- Henckes A. Pulmonary oedema in scuba-diving: frequency and seriousness about a series of 19 cases. Annales Françaises D’anesthésie Et De Réanimation. 2008;27(9):694–699.
- Peacher DF, Pecorella SRH, Freiberger JJ, et al. Effect of hyperoxia on ventilation and pulmonary hemo- dynamics during immersed prone exercise at 4.7 ATA: possible implications for immersion pulmonary edema. J Appl Physiol. 2010;109:68e78.
- Thorsen E, Skogstad M, Reed JW. Subacute effects of inspiratory resistive loading and head-out water immersion on pulmonary function. Undersea Hyperb Med. 1999;26:137–141.
- Moon RE et al. Swimming-Induced Pulmonary Edema: Pathophysiology and Risk Reduction With Sildenafil. Circulation. 2016; CIRCULATIONAHA.115.019464.
- Edmonds C, Lippmann J, Lockley S, et al. Scuba divers’ pulmonary edema: recurrences and fatalities. Diving Hyperb Med. 2012;42 (1):40–44.
- Kumar, Manish, and Paul D. Thompson. "A literature review of immersion pulmonary edema." The Physician and Sportsmedicine 47.2 (2019): 148-151.