What are the immediate steps to take if someone experiences vomiting and dizziness after scuba diving?

Immediate Management of Post-Scuba Diving Vomiting and Dizziness

Activate emergency medical services immediately and administer 100% oxygen while preparing for urgent hyperbaric oxygen therapy, as these symptoms indicate potentially life-threatening decompression illness or arterial gas embolism requiring treatment within hours to prevent permanent neurological damage or death. 1, 2

Critical Initial Assessment and Actions

Immediate Life-Saving Steps

• Place the patient on 100% high-flow oxygen immediately via non-rebreather mask at 15 L/min, as hypoxia is the primary threat to survival and oxygen reduces bubble size in both decompression sickness and arterial gas embolism 1, 2

• Activate EMS without delay - vomiting and dizziness after diving represent potentially fatal conditions requiring immediate transport to a hyperbaric facility 3, 2

• Position the patient supine (flat on their back) - do not place in Trendelenburg or left lateral decubitus position, as these historical practices are not supported by evidence 1

• Assess airway, breathing, and circulation - check for altered consciousness, respiratory distress, or cardiovascular instability that may require advanced life support 1

Rapid Differential Diagnosis

The combination of vomiting and dizziness post-dive indicates one of three life-threatening conditions:

Arterial Gas Embolism (AGE):

• Occurs during or immediately after ascent (typically within minutes) 1, 2
• Presents with sudden neurological symptoms including dizziness, altered consciousness, seizures, or focal deficits 1
• Can occur even after shallow dives without rapid ascent 2
• Requires immediate hyperbaric oxygen therapy to prevent permanent brain damage or death 2

Decompression Sickness (DCS):

• Symptoms typically develop within 1-6 hours post-dive but can occur up to 24-48 hours later 1, 4
• Inner ear DCS specifically causes vertigo, tinnitus, nausea, vomiting, and hearing loss 4
• Can occur after shallow recreational dives, not just deep technical dives 4, 5
• Neurological symptoms may indicate cerebral involvement requiring urgent recompression 1

Pulmonary Barotrauma:

• Occurs during ascent when expanding gas cannot escape the lungs 1
• May present with chest pain, dyspnea, hoarseness (pneumomediastinum), or neurological symptoms if gas enters arterial circulation 1
• Can lead to arterial gas embolism with catastrophic neurological consequences 1

Essential History to Obtain During Transport

Dive Profile Details:

• Maximum depth and total dive time 6, 5
• Rate of ascent (rapid/uncontrolled ascent increases AGE risk) 1, 7
• Number of dives in past 24 hours (repetitive diving increases DCS risk) 1
• Any missed decompression stops or safety stops 1

Symptom Timeline:

• Exact time of symptom onset relative to surfacing (immediate = AGE; delayed = DCS) 1, 4
• Progression of symptoms (worsening indicates urgent intervention needed) 2
• Associated symptoms: headache, visual changes, weakness, numbness, hearing loss, chest pain 1, 7, 4

Critical Risk Factors:

• History of asthma or lung disease (increases barotrauma risk) 1
• Patent foramen ovale (allows paradoxical gas embolism) 5
• Recent respiratory infection (increases pulmonary edema risk) 1

Hospital Management Algorithm

Upon Emergency Department Arrival

Continue 100% oxygen - maintain throughout evaluation and transport to hyperbaric chamber 2

Obtain immediate neurological examination looking for:

• Level of consciousness (Glasgow Coma Scale) 2
• Focal neurological deficits (weakness, sensory loss, visual field defects) 1, 7
• Cerebellar signs (ataxia, dysmetria) 4
• Cranial nerve abnormalities 7

Perform targeted physical examination:

• Auscultate lungs for crackles (pulmonary edema) or decreased breath sounds (pneumothorax) 1
• Palpate for subcutaneous emphysema in neck (pneumomediastinum) 1
• Assess for cardiac arrhythmias (atrial fibrillation can complicate AGE) 2

Obtain essential imaging only if it does not delay hyperbaric treatment:

• Chest X-ray if pneumothorax or pneumomediastinum suspected 1
• CT head only if focal neurological deficits present and diagnosis unclear 7
• Do NOT delay hyperbaric oxygen for routine imaging 2

Hyperbaric Oxygen Therapy Decision

Treat with hyperbaric oxygen if ANY of the following present:

• Neurological symptoms (dizziness, altered consciousness, focal deficits) 1, 2
• Persistent vomiting suggesting vestibular or CNS involvement 4
• Symptoms occurring within 24 hours of diving 1, 4
• Any doubt about diagnosis - when in doubt, treat 2, 4

Treatment protocol:

• U.S. Navy Treatment Table 6 is standard for both AGE and DCS 4
• Initiate within 6 hours of symptom onset for optimal outcomes, though delayed treatment (even 30+ hours) can still provide benefit 2, 5
• Continue 100% oxygen during transport to hyperbaric facility 2

Critical Pitfalls to Avoid

Do not assume shallow dives are safe - both AGE and DCS can occur after recreational depths of 10-15 meters 2, 4, 5

Do not wait for "classic" presentations - symptoms can be subtle or atypical, and delayed treatment significantly worsens outcomes 2, 4

Do not perform Heimlich maneuver or abdominal thrusts - these are contraindicated and potentially dangerous in diving emergencies unless airway obstruction from foreign body is confirmed 1

Do not delay hyperbaric treatment for extensive diagnostic workup - time to recompression is the single most important factor determining neurological outcome 2, 4

Do not discharge patients with "mild" symptoms - seemingly minor vestibular symptoms can represent serious inner ear DCS requiring hyperbaric treatment to prevent permanent hearing loss 4

Supportive Care During Transport and Treatment

• Intravenous fluid resuscitation with normal saline to maintain adequate hydration and perfusion 2
• Antiemetics for persistent vomiting (ondansetron preferred) 4, 5
• Avoid sedatives unless absolutely necessary, as they may mask neurological deterioration 2
• Continuous monitoring of vital signs, oxygen saturation, and neurological status 2