Key Points
- Use the highest‑yield diagnostic test early; do not let testing delay time‑critical therapy.
- Set objective targets and reassess frequently.
- Plan definitive source control or disease‑specific therapy when indicated; document follow‑up and patient education.
Algorithm
- Remove from exposure; start 100% oxygen immediately; obtain COHb via co‑oximetry.
- Assess for severe features (syncope, neuro deficits, COHb ≥25%—≥15% in pregnancy, ischemia); consult HBOT center.
- Monitor until symptoms resolve and COHb falls; counsel on delayed neurologic syndrome and follow‑up.
Clinical Synopsis & Reasoning
CO binds hemoglobin and impairs cellular respiration. Treat immediately with 100% oxygen; consider hyperbaric oxygen for severe poisoning (neurologic symptoms, COHb ≥25%—lower thresholds in pregnancy—or cardiac ischemia). Monitor for delayed neurocognitive sequelae.
Treatment Strategy & Disposition
Stabilize ABCs. Initiate guideline‑concordant first‑line therapy with precise dosing and continuous monitoring. Escalate to advanced/procedural interventions based on explicit failure criteria. Define ICU, step‑down, and ward disposition triggers; involve specialty teams early.
Epidemiology / Risk Factors
- Risk varies by comorbidity and precipitants; see citations for condition‑specific data.
Investigations
| Test | Role / Rationale | Typical Findings | Notes |
|---|---|---|---|
| Co‑oximetry (venous/arterial) | Diagnosis | Elevated COHb | Pulse oximetry unreliable |
| EKG/troponin, lactate | Severity/complications | Ischemia, tissue hypoxia | Guide HBOT need |
| Pregnancy test (females of childbearing age) | Lower HBOT threshold | Fetal risk | — |
Pharmacology
| Medication/Intervention | Mechanism | Onset | Role in Therapy | Limitations |
|---|---|---|---|---|
| 100% oxygen via NRB or ET tube | Displacement therapy | Immediate | Reduce COHb half‑life | Continue until asymptomatic and COHb near normal |
| Hyperbaric oxygen therapy (selected) | HBOT | Hours | Consider for severe features or pregnancy | Availability/logistics vary |
| Supportive care (fluids, seizure control) | Symptomatic | Immediate | Treat complications | — |
Prognosis / Complications
- Outcome depends on timeliness of diagnosis and definitive therapy; monitor for complications.
Patient Education / Counseling
- Provide red‑flag education, adherence guidance, and explicit return precautions; arrange timely specialty follow‑up.
References
- CDC/UHMS guidance on CO poisoning and HBOT — Link