The Center for Hyperbaric Medicine, in Seattle, maintains an on-call team that responds to emergencies 24 hours a day. Emergency patients are referred to the Center for Hyperbaric Medicine through the (24/7) Admissions Center: (206) 341-1141.

Carbon Monoxide Poisoning

Carbon Monoxide (CO) is a colorless, odorless gas. Common sources are: incomplete combustion from fossil fuels; automobiles, boats, generators, barbecues and house fires.

If a patient has vague flu-like symptoms, nausea, headache, confusion or loss of consciousness, it may be carbon monoxide poisoning. A cherry red appearance is rarely seen. Oxygen saturation monitors do not reflect accurate oxygenation.

Indications for Hyperbaric Treatment:

Patients with documented exposure to CO (COHb level greater than 2 percent in a nonsmoker and greater than 10 percent in a smoker) within the previous 24 hours and any one or more of the following:

  • Loss of consciousness
  • COHb level > 25 percent
  • Any neurological deficits
  • Cardiac ischemia
  • Age > 50 years
  • Metabolic acidosis (calculated base excess lower than -2.0 mmol/liter or a lactate concentration or > 2.5 mmol/liter

EMS Management of Carbon Monoxide Poisoning

100 percent oxygen by non-rebreather mask at 15 liters/min.

CO: Delay from onset of symptoms < 24 hours: intravenous hydration - normal saline 1 liter over 2 hours followed by 250 cc/hour (unless pulmonary edema is present).

Delay from onset of symptoms > 24 hours: encourage fluids. Electrocardiogram, chest X-ray, arterial blood gases, establish intravenous access.

As dictated by patient condition: endotracheal intubation, arterial catheter, urinary catheter, NG tube.

Hyperbaric Oxygen Therapy (HBO2)

Immediate recompression is the treatment of choice to:

  • Reverse hypoxia
  • Reverse symptoms
  • Limit long term neurological sequelae

ER CO Poisoning Information Protocol

Capture this information:

  • Patient demographics
  • Carboxyhemoglobin level
  • When was CO exposure?
  • Source of CO
  • Does patient speak English?
  • Symptoms - common symptoms include chest pain, confusion, dizziness, fatigue, headache, memory complaints, nausea/vomiting, shortness of breath, loss of consciousness
  • Was the CO poisoning accidental or intentional?
  • If intentional, get results of toxicology screen
  • Is patient pregnant?
  • Is there evidence of cardiac injury?
  • What is the current clinical status?
  • Contraindications to hyperbaric exposure (relative or absolute)
    • Evidence of pneumothorax
    • History of seizures
    • Hemodynamic instability
    • Significant heart or lung disease

Emergency patients are referred to the Center for Hyperbaric Medicine through the (24/7) Admissions Center: (206) 341-1141.

   [Back to Top]

Decompression Sickness and Arterial Gas Embolism

Decompression Sickness (DCS)

DCS is a micro-bubble disease that can follow exposure to high pressure (diving) or as a result of rapid ascent to high altitudes. DCS can occur even if decompression limits are observed or following uneventful dives.

Diagnosis of Decompression Sickness:

  • History of recent exposure to breathing compressed air under water.
  • Symptoms consistent with DCS:
    • Musculoskeletal - Joint pain
    • Neurological - Numbness or other sensory deficits, tingling, weakness or paralysis, ataxia or other vestibular symptoms, extreme fatigue, cognitive deficits
    • Cutaneous - Skin blotching, itching
    • Pulmonary - Dyspnea
  • Onset ranges from immediate to 48 hours
  • Magnitude of exposure is not a reliable guide to severity of disease.

Arterial Gas Embolism (AGE)

Arterial gas bubbles resulting from pulmonary over-pressurization, alveolar rupture, and entry of air bubbles into the vasculature. AGE is primarily a diving accident, but may follow escape from a submerged vehicle or may be an iatrogenic complication.

Diagnosis of Arterial Gas Embolism:

  • Immediate onset of symptoms
  • Panic or uncontrolled ascent during diving
  • Evidence of anatomic or physiologic airway obstruction
  • Symptoms consistent with AGE:
    • Neurological - Stroke-like symptoms, numbness or other sensory deficits, tingling, weakness or paralysis
    • Pulmonary (due to barotraumas) - Dyspnea, hemoptysis, pneumothroax (seen only occasionally)
    • Cardiac (due to coronary embolization) - S-T changes, dysrhythmias, tachycardia
  • Can occur in three to four feet of water
  • Recent invasive medical procedure (iatrogenic)

EMS Management of Decompression Sickness and Arterial Gas Embolism

100 percent oxygen by non-rebreather mask at 15 liters/min should be administered immediately for either DCS or AGE.

DCS: Delay from onset of symptoms < 24 hours: intravenous hydration - normal saline 1 liter over 2 hours followed by 250 cc/hour (unless pulmonary edema present).

Delay from onset of symptoms > 24 hours: encourage fluids.
AGE: Electrocardiogram, chest X-ray, arterial blood gases, establish intravenous access.
 
DCS or AGE: As dictated by patient condition: endotracheal intubation, arterial catheter, urinary catheter, NG tube.

Hyperbaric Oxygen Therapy (HBO2)

Immediate recompression is the treatment of choice.

  • Inhibits progression of the disease
  • Reverses symptoms
  • Limits reoccurrence of symptoms
  • Prevents long-term neurologic and orthopedic sequelae.

If symptoms resolve with oxygen administration, the patient must be referred for HBO2 as symptoms frequently return.

ER Diving Injury Information Protocol

Capture this information:

  • Patient demographics
  • Symptoms - common symptoms include joint pain, numbness, tingling, headache, fatigue, dizziness, rash, weakness, bowel and bladder dysfunction
    • Date and time of onset of first symptom
    • Most serious clinically significant symptom
    • Note if symptoms occurred prior to dive or at depth
  • Dive history
    • Date and time of last dive
    • Maximum depth and time of last dive
    • Total number of dives and over what time period
    • Any problems with dive(s)
    • Altitude exposure after dives
  • Physical examination
    • Any objective neurological findings? (cranial nerves, strength, sensation to light touch, gait, finger-to-nose)
  • Contraindications to hyperbaric exposure (relative or absolute)
    • Evidence of pneumothorax
    • History of seizures
    • Hemodynamic instability
    • Significant heart or lung disease

Emergency patients are referred to the Center for Hyperbaric Medicine through the (24/7) Admissions Center: (206) 341-1141.

   [Back to Top]