How to manage a patient with an EtCo2 (End-Tidal Carbon Dioxide) level of 80-86?

Management of Elevated EtCO2 of 80-86 mmHg

An EtCO2 of 80-86 mmHg is a medical emergency that requires immediate intervention, as it indicates severe hypoventilation or a potential malignant hyperthermia reaction that can lead to significant morbidity and mortality if not promptly addressed.

Immediate Assessment and Differential Diagnosis

Primary Considerations

• An unexplained, unexpected increase in carbon dioxide production with EtCO2 values of 80-86 mmHg strongly suggests malignant hyperthermia (MH), especially if the patient has recently been exposed to triggering agents such as inhalational anesthetics or suxamethonium 1
• This extreme elevation in EtCO2 indicates severe hypoventilation that cannot be easily controlled by increasing minute ventilation 1
• Other causes of severely elevated EtCO2 include:
  • Respiratory depression from inhalation poisoning 2
  • Inadequate mechanical ventilation settings 3
  • Severe COPD exacerbation with respiratory failure 4

Associated Clinical Features to Assess

• Monitor for increasing heart rate - an upward trend in heart rate accompanying increased carbon dioxide production is highly suggestive of MH 1
• Check for temperature elevation, although it may still be within normal range early in an MH reaction 1
• Look for muscle rigidity, which may occur during an MH reaction even in the presence of non-depolarizing neuromuscular blockade 1
• Assess for signs of hemodynamic instability which may accompany severe hypercapnia 1

Immediate Management

For Suspected Malignant Hyperthermia

• Immediately discontinue all triggering agents (inhalational anesthetics) 1
• Deliver 100% oxygen at maximum flow and increase the patient's minute ventilation to 2-3 times normal 1
• Administer intravenous dantrolene immediately 1
• Initiate active body cooling 1
• Delay in commencing treatment of MH is associated with increased mortality and complications 1

For Other Causes of Severe Hypercapnia

• Ensure patent airway and adequate oxygenation 3
• If mechanically ventilated, check for equipment malfunction, circuit leaks, or inadequate ventilator settings 3
• Adjust ventilation parameters to normalize EtCO2 3
• Obtain arterial blood gas analysis to confirm the degree of hypercapnia and assess pH 5
• Consider permissive hypercapnia only after ruling out conditions requiring urgent intervention 3

Monitoring During Management

• Continuously monitor EtCO2, heart rate, blood pressure, and oxygen saturation 1
• An increase in EtCO2 might be the only early clue to potential respiratory compromise before oxygen desaturation occurs 2
• Document trends in EtCO2 values rather than isolated readings 3
• In patients with cardiac arrest, if PETCO2 is <10 mm Hg, immediately attempt to improve CPR quality 3
• A sudden decrease in EtCO2 during management may indicate ROSC in cardiac arrest scenarios 6

Special Considerations

• In COPD patients, the correlation between PaCO2 and EtCO2 may be weaker, especially in those on non-invasive ventilation 4
• For intubated COPD patients, mainstream EtCO2 measurement can accurately predict PaCO2 4
• In poisoned patients, an EtCO2 ≥50 mm Hg has limited predictive value for complications (sensitivity 46%, specificity 80%) 7
• Early detection of MH using EtCO2 monitoring has been shown to lead to prompt treatment and improved outcomes 8

Follow-up Management

• Once EtCO2 begins to normalize, continue close monitoring as rebound increases may occur 3
• Reassess ventilation parameters regularly until EtCO2 normalizes 3
• For confirmed MH cases, follow established protocols for ongoing management and prevention of recurrence 1
• Consider ICU admission for patients with severe hypercapnia requiring ongoing ventilatory support 7