Capnographic monitoring of ventilatory status during moderate (conscious) sedation

BACKGROUND

Moderate (conscious) sedation is required to perform endoscopic procedures. Capnography provides a means for continuous, real-time monitoring of ventilation and may also decrease the incidence of oversedation.

METHODS

A retrospective examination of all endoscopic procedures performed from January through December 2001 at our institution was undertaken to determine the potential benefits of capnographic monitoring.

RESULTS

In 4,846 endoscopic procedures performed without capnography, adverse outcomes related to moderate sedation were noted in 14 cases (0.29%). A subset of patients at higher risk for moderate sedation was identified. There were no cases of oversedation in 600 cases monitored with capnography. The complication rates were not significantly different for the two groups ( p = 0.30, NS).

CONCLUSION

The addition of capnography during moderate sedation endoscopy does not appear to significantly lower anesthesia-related morbidity. However, in cases requiring moderate sedation for prolonged procedures, in older patients with comorbidities, or in instances where respiratory excursion of the patient is obscured from view, practitioners should nonetheless consider capnography.

Capnography. A key underutilized technology

Based on the multiple applications and the potential cost savings, every ICU should have enough capnography for all intubations and probably for all mechanically ventilated patients. Of the multiple clinical applications of capnography, most attention should be focused on its use with intubation and resuscitation. Other applications, such as blood gas and ventilation-perfusion scan reduction, should be instituted after the primary areas have been implemented. While capnography modules may appear to be expensive at first glance, an analysis of their clinical application reveals they can save the hospital hundreds of thousands of dollars beyond the purchase price.