CO2 narcosis
Contents
Background
- Increased CO2 in the blood leading to depressed mental status
- Most commonly seen in acute exacerbations of obstructive pulmonary diseases
- Can also be seen in SCUBA divers
Clinical Features
- Headache
- Confusion
- Lethargy
- Propensity for arrhythmias
- Seizure
- Coma/death
Differential Diagnosis
Altered mental status
Diffuse brain dysfunction
- Hypoxic encephalopathy
- Acute toxic-metabolic encephalopathy (Delirium)
- Hypoglycemia
- Hyperosmolar state (e.g., hyperglycemia)
- Electrolyte Abnormalities (hypernatremia or hyponatremia, hypercalcemia)
- Organ system failure
- Hepatic Encephalopathy
- Uremia/Renal Failure
- Endocrine (Addison's disease, Cushing syndrome, hypothyroidism, myxedema coma, thyroid storm)
- Hypoxia
- CO2 narcosis
- Hypertensive Encephalopathy
- Toxins
- TTP / Thrombotic thrombocytopenic purpura
- Alcohol withdrawal
- Drug reactions (NMS, Serotonin Syndrome)
- Environmental causes
- Deficiency state
- Wernicke encephalopathy
- Subacute Combined Degeneration of Spinal Cord (B12 deficiency)
- Vitamin D Deficiency
- Zinc Deficiency
- Sepsis
- Osmotic demyelination syndrome (central pontine myelinolysis)
- Limbic encephalitis
Primary CNS disease or trauma
- Direct CNS trauma
- Diffuse axonal injury
- Subdural/epidural hematoma
- Vascular disease
- Intraparenchymal hemorrhage
- SAH
- Stroke
- Hemispheric, brainstem
- CNS infections
- Neoplasms
- Paraneoplastic Limbic Encephalitis]
- Malignant Meningitis
- Pancreatic Insulinoma
- Seizures
- Nonconvulsive status epilepticus
- Postictal state
- Dementia
Psychiatric
- Acute psychosis
- Excited delirium
- Malingering
Evaluation
- VBG (ABG not required to make this diagnosis[1])
Management
- Hyperventilation with either NIPPV or intubation/mechanical ventilation depending on severity and patient's mental status
Disposition
- Admission to a monitored setting
See Also
External Links
References
- ↑ McCanny P, Bennett K, Staunton P, McMahon G. Venous vs arterial blood gases in the assessment of patients presenting with an exacerbation of chronic obstructive pulmonary disease. Am J Emerg Med. 2012; 30(6):896-900.
Authors:
Neil Young, Nicole Zadzilka, Daniel Ostermayer, Ross Donaldson