CHS Decompression Sickness & Diving Medicine Flashcards

Which laboratory or imaging finding most directly confirms the diagnosis of pulmonary barotrauma with pneumothorax in a diver?

Answer: Chest radiograph showing air in the pleural space and mediastinum

Chest X-ray demonstrating pleural air (pneumothorax) or mediastinal air (pneumomediastinum) confirms pulmonary overinflation injury, a critical finding before HBOT as tension pneumothorax must be addressed first.

What is the significance of patent foramen ovale (PFO) in the context of DCS risk for divers?

Answer: PFO allows venous bubbles to pass directly to the arterial circulation, increasing risk of paradoxical embolism and AGE-like symptoms

A PFO creates a right-to-left shunt that can allow venous nitrogen bubbles to bypass the pulmonary filter and enter the arterial circulation, dramatically increasing risk of stroke-like DCS presentations.

Inner ear DCS (vestibular DCS) presents with which classic triad of symptoms?

Answer: Vertigo, tinnitus, and sensorineural hearing loss

Vestibular DCS causes bubble formation in the highly vascular inner ear, producing the classic triad of vertigo, tinnitus, and hearing loss due to disrupted cochlear and vestibular perfusion.

A CHS is treating a diver with Type II DCS who is also taking aspirin. What is the rationale for using aspirin as an adjunct in DCS management?

Answer: Aspirin's antiplatelet effect reduces platelet aggregation on bubble surfaces, mitigating secondary thrombosis

Gas bubbles trigger platelet aggregation and complement activation; aspirin inhibits platelet function to reduce the secondary thrombotic and inflammatory injury superimposed on bubble-mediated damage.

What is the correct fluid resuscitation approach for a diver presenting with DCS?

Answer: Administer isotonic oral or intravenous fluids to maintain adequate hydration and promote nitrogen off-gassing

Adequate hydration with isotonic fluids supports tissue perfusion, reduces blood viscosity, and optimizes the gradient for nitrogen diffusion from tissues into circulation for pulmonary excretion.

According to Divers Alert Network (DAN) guidelines, after successful HBOT treatment for DCS, what is the minimum recommended surface interval before a diver can return to diving?

Answer: At least 2 weeks, or as determined by the treating physician based on full symptom resolution

DAN and UHMS recommend a minimum of 2 weeks (often longer) before returning to diving after DCS, ensuring complete neurological recovery and avoiding re-injury of recently healed tissue.