What are the treatments for different types of Decompression Sickness (DCS)?

Treatment of Decompression Sickness by Type

For all types of decompression sickness (DCS), immediate high-flow oxygen administration is the critical first-line intervention, followed by hyperbaric oxygen therapy as definitive treatment for most cases except mild altitude-related DCS. 1, 2, 3

Immediate Management (All DCS Types)

• Administer 100% oxygen immediately at the highest available concentration, ideally 15 L/min via reservoir mask if available, as oxygen accelerates nitrogen elimination and reduces bubble size 1, 2, 3
• Begin aggressive fluid resuscitation with isotonic, glucose-free crystalloid solutions (oral if patient can tolerate, otherwise intravenous) to address the capillary leak syndrome and hypovolemia that characterizes DCS 4, 3, 5
• Perform focused neurological examination to classify severity and guide treatment intensity 2, 3
• Arrange immediate transport to hyperbaric facility while maintaining oxygen therapy during transport 2, 3

Critical pitfall: Do not delay oxygen administration or transport while obtaining detailed history—begin oxygen first, then gather information 2, 3

Type I DCS (Musculoskeletal/Mild)

Type I DCS presents with joint pain, lymphedema, skin rash, or fatigue without neurological involvement.

• High-flow oxygen alone may be sufficient for mild cases, particularly altitude-related DCS, with resolution often occurring within hours 1, 3
• If symptoms persist beyond 30-60 minutes of oxygen therapy or worsen, proceed to hyperbaric oxygen treatment 3
• Use U.S. Navy Treatment Table 6 (or equivalent): 100% oxygen at 2.82 atmospheres absolute (60 feet of seawater equivalent) for cases requiring recompression 3, 5
• Joint pain typically responds dramatically to recompression, often resolving within minutes of reaching treatment depth 5

Type II DCS (Neurological/Severe)

Type II DCS involves neurological symptoms (motor weakness, sensory changes, ataxia), cardiorespiratory manifestations (pulmonary edema, shock), or altered consciousness.

• Hyperbaric oxygen is mandatory and should not be delayed even in critically ill patients requiring vasopressor support 4, 3
• Use U.S. Navy Treatment Table 6 as initial treatment: 100% oxygen at 2.82 atmospheres absolute 3
• For severe cases with delayed presentation or blood-brain barrier dysfunction, consider deeper recompression to 4 atmospheres absolute using 50% oxygen/50% helium mixture, which provides superior oxygen delivery without oxygen toxicity risk 5
• Administer aggressive volume resuscitation: expect to give 20+ liters of crystalloid in first 24-48 hours for severe cases with shock, as bubble-endothelial interactions cause massive capillary leak 4
• Add albumin boluses for refractory hypotension unresponsive to crystalloid alone 4
• Provide vasopressor support (typically requiring 2-3 agents) during initial hyperbaric treatment if needed, but recognize this is usually time-limited (24-48 hours) as capillary leak resolves 4

Critical consideration: Neurological DCS may worsen initially during standard oxygen therapy due to blood-brain barrier dysfunction; this does not indicate treatment failure but rather the need for continued or repeated hyperbaric sessions 5

Adjunctive Therapies

• Corticosteroids (e.g., dexamethasone) are reasonable adjuncts when therapy has been delayed beyond 24 hours, particularly for neurological manifestations, though evidence is limited 5
• Avoid glucose-containing fluids as they may worsen neurological outcomes 3
• Continue oxygen between hyperbaric treatments at highest tolerable concentration 3

Treatment Course and Follow-up

• Most cases require 1-2 hyperbaric treatments for complete resolution 3
• Continue additional treatments (typically no more than one treatment per day) until clinical stability is achieved or no further improvement occurs 3
• Severe cases with delayed presentation may require extended courses of 5-10+ treatments 4, 3
• Monitor for recurrence of symptoms, which may indicate need for additional hyperbaric sessions 5

Important caveat: The absence of tachypnea in a hypoxic DCS patient suggests severe underlying pathology (respiratory muscle fatigue, central depression, or cardiovascular collapse) and mandates immediate aggressive intervention 6