Pulmonary oedema and hyponatraemia after an ironman triathlon

Abstract

A 36-year-old man presented with symptoms of acute pulmonary oedema at the conclusion of the Australian ironman triathlon. He was alert, orientated, with an oxygen saturation of 75% on room air. Chest examination revealed bilateral basal crepitations. Serum sodium was 120 mmol/L and chest x ray revealed bilateral basal opacities. He was treated for acute pulmonary oedema with prompt improvement and given 200 ml of intravenous hypertonic saline followed by normal saline. Serum sodium decreased to 117 mmol/L and 30 hours after presentation he had a seizure. He fully recovered and was discharged 5 days after admission. This case highlights that exercise-associated hyponatraemia and pulmonary oedema are still not widely understood and there is still a reluctance to treat hyponatraemia aggressively with ongoing hypertonic saline.

Pulmonary Aspects of Exercise and Sports

“…13 None of the athletes had evidence of lung edema before the event, while 75% showed evidence of pulmonary edema immediately post-race, and 42% had persistent findings of pulmonary edema 12 hours post-race. Their data and several case reports [14][15][16] have demonstrated that extreme exercise can result in pulmonary edema and support the findings of West et al …”

“…Their data and several case reports [14][15][16] have demonstrated that extreme exercise can result in pulmonary edema and support the findings of West et al …”

Statement of the 3rd International Exercise-Associated Hyponatremia Consensus Development Conference, Carlsbad, California, 2015

“…The dose and route of HTS administration should be based on the severity of clinical symptoms and the available HTS formulations, as discussed in box 4. Numerous case reports and case series have validated the efficacy and safety of intravenous HTS administration in symptomatic EAH,8 38 48 49 52 62 72 82 91 100 122 154 with one runner receiving 950 mL of 3% over a 7 h period without complications42 and a swimmer receiving 40 mL of 20% HTS51 without complication.

Recommended treatment for both mild and severe (life-threatening) symptomatic exercise-associated hyponatraemia (EAH) in the field or in the hospital

Treatment of mild EAH

Observation (restrict hypotonic and isotonic fluids until urinating freely)

Administration of intravenous HTS ( see below for severe symptomatology )

Administration of oral HTS:

▸  Concentrated bouillon (4 bouillon cubes in 125 mL, ½ cup of water)

▸  3% NaCl (100 mL), preferably with the addition of a flavouring (eg, Crystal Light, Kool Aid)

▸  Equivalent volumes of other solutions of high sodium concentration (eg, 3–9%)

Treatment of severe EAH

Administration of intravenous HTS:

▸ 100 mL bolus of 3% NaCl, repeated twice if there is no clinical improvement ( 10 min intervals have been recommended, but this should be determined by the clinical judgement of the treating physician )

▸ Comparable amounts of more concentrated Na + -containing solutions (eg, 10 mL of 20% NaCl; 50 mL of 8.4% NaHCO 3 ) may be used as an alternative to 3% NaCl .

▸  In some situations ( ie, more severe encephalopathic symptomatology such as seizures, coma or signs of impending brain herniation ) , it may be appropriate to administer larger HTS boluses initially rather than waiting to assess clinical improvement after repeated smaller boluses .

HTS represents hypertonic saline.

…”

“…This treatment is based on the capacity of an intravenous HTS bolus to increase the serum [Na + ] 2–5 mmol/L, resulting in a concomitant decrease of intracranial pressure and improvement in symptoms 5 6. This approach does not pose any substantial danger to the patient, because osmotic demyelination syndrome has not been associated with either the rapid correction of acute hyponatraemia (ie, <48 h duration) in clinical159 or exercise settings8 38 48 49 52 62 72 82 91 100 122 154 or with the limited increase in [Na + ] produced by a single bolus of HTS 139 160. Also, of note, if the athlete was wrongly assumed to have EAHE, the administration of HTS in small boluses is not associated with any negative consequences and serves as an excellent volume expander 139…”

Lung injury related to extreme environments

“…Evidence for pulmonary oedema has been shown in competitive rowers [28], during exertion in dry cold environments and in cases of emotional stress and sexual intercourse [29], in addition to long distance runners and triathletes [30][31][32][33][34][35][36][37][38][39][40] and competitive cyclists [41,42]. The importance of mild oedema in reducing exercise capacity has been questioned [43].…”