Misdiagnosis Not your basic acute sinusitis Mary Thomason March 8, 2006

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Case Presentation 55 yo female with PMH significant for presumed acute sinusitis in March/April of 2005 requiring 6 weeks of antibiotics who presented with HA and nasal congestion. 55 yo female with PMH significant for presumed acute sinusitis in March/April of 2005 requiring 6 weeks of antibiotics who presented with HA and nasal congestion. 12/2/05 at urgent care 12/2/05 at urgent care dx: Acute Sinusitis tx: 2 Z-Paks 12/6/05 in clinic 12/6/05 in clinic cc: headache dx:? tx: complete antibiotics and follow up in one week

Case Presentation 12/16/05 clinic followup 12/16/05 clinic followup cc: headache and nasal congestion dx: persistent URI symptoms tx: nasal steroids and sinus CT scan 12/19/05 radiology 12/19/05 radiology CT scan negative for acute sinusitis or congestion

Case Presentation 12/30/05 clinic follow up 12/30/05 clinic follow up Dx: Carbon Monoxide (CO) Poisoning Dx: Carbon Monoxide (CO) Poisoning

Objectives Recognize symptoms of CO exposure Recognize symptoms of CO exposure Diagnosis of CO exposure Diagnosis of CO exposure Treatment of CO exposure Treatment of CO exposure Prevention of CO exposure Prevention of CO exposure

Physiology CO diffuses rapidly over the alveolar membrane CO diffuses rapidly over the alveolar membrane Binds reversibly with 200-fold affinity to Hgb Binds reversibly with 200-fold affinity to Hgb Shifts the oxyhemoglobin dissociation curve Shifts the oxyhemoglobin dissociation curve

Statistics Leading cause of accidental poisoning death in the US Leading cause of accidental poisoning death in the US Estimated 15,000 treated annually in ED Estimated 15,000 treated annually in ED Approximate 500 deaths annually Approximate 500 deaths annually JAMA vol. 293, no. 10, 3/9/05,

CO Sources Furnaces Furnaces Generators Generators Gas heaters Gas heaters Motor vehicles (cars, trucks, tractors, boats) Motor vehicles (cars, trucks, tractors, boats) Fires Fires

Exposures Majority of CO exposures occur in the fall and winter months Majority of CO exposures occur in the fall and winter months 64.3% occur in the home 64.3% occur in the home 18.5% due to faulty furnaces 18.5% due to faulty furnaces 9% motor vehicles 9% motor vehicles JAMA vol. 293, no. 10, 3/9/05,

CO Exposure After Katrina 51 cases reported by HBO2 facilities of AL, LA, MS 51 cases reported by HBO2 facilities of AL, LA, MS 46 nonfatal, 5 deaths 46 nonfatal, 5 deaths The source for all but one of the non-fatal cases was exhaust from a portable generator. The source for all but one of the non-fatal cases was exhaust from a portable generator. MMWR vol. 54, no. 39, 10/7/05,

Symptoms of Mild Poisoning Throbbing temporal or frontal HA Throbbing temporal or frontal HA Fatigue Fatigue Weakness Weakness Lightheadedness Lightheadedness Nausea/Vomiting Nausea/Vomiting Shortness of Breath Shortness of Breath

Symptoms of Moderate Poisoning Severe HA Severe HA Tachycardia/Tachypnea Tachycardia/Tachypnea Flushing, perspiration Flushing, perspiration Diminished manual dexterity/prolonged reaction time Diminished manual dexterity/prolonged reaction time Impaired judgment/confusion Impaired judgment/confusion Vision changes (darkened, blurred) Vision changes (darkened, blurred) Tinnitus Tinnitus

Symptoms of Severe Poisoning Syncope Syncope Seizures Seizures MI MI Dysrhythmias Dysrhythmias Respiratory failure/ pulmonary edema Respiratory failure/ pulmonary edema Coma Coma Death Death

Delayed Effects Depression Depression Dementia/Memory Loss Dementia/Memory Loss Psychosis Psychosis Peripheral neuropathy Peripheral neuropathy Parkinsonism Parkinsonism Visual impairment Visual impairment Chorea Chorea

Diagnosis of CO poisoning Have a high clinical suspicion Have a high clinical suspicion Determine the COHb level when the pt is first seen and repeat q2-4 hours until pt is asymptomatic or the value is normal. Determine the COHb level when the pt is first seen and repeat q2-4 hours until pt is asymptomatic or the value is normal. If symptomatic or COHb greater than 20% monitor with ECG, lytes, CK, UA, ABG to evaluate for sequella If symptomatic or COHb greater than 20% monitor with ECG, lytes, CK, UA, ABG to evaluate for sequella Poisindex (accessed feb 2006)

Range of Toxicity Normal COHb is 1-3% Normal COHb is 1-3% Cigarette smokers increase their levels by 5% per pack per day (may tolerate up to 10%) Cigarette smokers increase their levels by 5% per pack per day (may tolerate up to 10%) Toxic affects appear at 15-20% Toxic affects appear at 15-20% COHb levels above 25% are considered severe COHb levels above 25% are considered severe Toxicity however is determined symptomatically (cardiovascular and mental status) Toxicity however is determined symptomatically (cardiovascular and mental status) NEJM vol. 347, no. 14, 10/3/02,

When to Hospitalize Neurologic signs Neurologic signs Abnormal ECG Abnormal ECG Metabolic Acidosis Metabolic Acidosis

Treatment Decontamination –move to fresh air Decontamination –move to fresh air Administer 100% oxygen (x 6 hours) Administer 100% oxygen (x 6 hours) Consider hyperbaric oxygen for severely poisoned (coma, seizures, MI) and pregnant patients at 3 atmospheres absolute. Consider hyperbaric oxygen for severely poisoned (coma, seizures, MI) and pregnant patients at 3 atmospheres absolute. NEJM vol. 347, no. 14, 10/3/02,

Guideline to prevent CO exposure Service heating system/water heater yearly Service heating system/water heater yearly Install a battery-operated CO detector and check the batteries twice yearly Install a battery-operated CO detector and check the batteries twice yearly Do not use charcoal grill or camp stove inside the home, garage, or near a window Do not use charcoal grill or camp stove inside the home, garage, or near a window Do not run vehicle inside garage Do not run vehicle inside garage Do no use stove or fire place that isn’t vented Do no use stove or fire place that isn’t vented Do not heat your home with a gas oven Do not heat your home with a gas oven JAMA vol. 293, no. 10, 3/9/05,

Summary Leading cause of accidental poisoning death in the US Leading cause of accidental poisoning death in the US Mild symptoms are similar to a viral illness, therefore a high index of suspicion is required Mild symptoms are similar to a viral illness, therefore a high index of suspicion is required CO poisoning is diagnosed symptomatically, but CO level testing can be helpful CO poisoning is diagnosed symptomatically, but CO level testing can be helpful The mainstay of treatment is oxygen therapy The mainstay of treatment is oxygen therapy Prevention is the key Prevention is the key

Questions?

References Poisindex Poisindex NEJM vol. 347, no. 14, 10/3/02, NEJM vol. 347, no. 14, 10/3/02, NEJM vol. 347, no. 14, 10/3/02, NEJM vol. 347, no. 14, 10/3/02, MMWR vol. 54, no. 39, 10/7/05, MMWR vol. 54, no. 39, 10/7/05, JAMA vol. 293, no. 10, 3/9/05, JAMA vol. 293, no. 10, 3/9/05, JAMA vol. 295, no. 4, 1/25/06, JAMA vol. 295, no. 4, 1/25/06, American Journal of Emergency Medicine, Vol. 23, 3/23/05, American Journal of Emergency Medicine, Vol. 23, 3/23/05,