Elevations in End-Tidal CO 2 With CO 2 Use During Pediatric Endoscopy With Airway Protection: Is This Physiologically...

Area of Science:

• Gastroenterology
• Pediatric Endoscopy
• Anesthesiology

Background:

• Gastrointestinal lumen insufflation is crucial for endoscopic visualization.
• Carbon dioxide (CO 2 ) is increasingly used to replace air for reduced post-procedure discomfort.
• Concerns exist regarding transient elevations in end-tidal CO 2 (EtCO 2 ) during pediatric procedures with CO 2 insufflation.

Purpose of the Study:

• To differentiate between eructated and absorbed CO 2 during pediatric esophagogastroduodenoscopy (EGD).
• To assess CO 2 absorption by monitoring EtCO 2 from a protected airway (laryngeal mask airway [LMA] or endotracheal tube [ETT]).
• To evaluate for hypoventilation by observing changes in minute ventilation (MV).

Main Methods:

• A double-blinded, randomized clinical trial compared CO 2 and air insufflation for pediatric EGD.
• Patients received airway protection via LMA or ETT.
• Tidal volume, respiratory rate, MV, and EtCO 2 were continuously recorded.

Main Results:

• Transient EtCO 2 elevations (≥60 mmHg) were more frequent with CO 2 than air (16% vs 5%, P=0.02).
• These elevations were more common with LMA than ETT.
• No significant difference in post-procedure pain; air insufflation led to more reported flatulence.

Conclusions:

• CO 2 insufflation increases the risk of transient EtCO 2 elevations during pediatric EGD, even with airway protection.
• These elevations were not associated with hypoventilation (changes in MV).
• While no adverse effects were noted, the minimal benefits of CO 2 suggest cautious use.