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Updated September 2022

Catastrophic sedation errors occur because capnography is not used

Catastrophic sedation errors occur because capnography is not used


Alan D. Kaye, MD, PhD states in 'Anesthesiology News' that inadequate monitoring during sedation continues to contribute to morbidity and mortality. He emphasizes that there is a real disconnect between the established guidelines and individual practices. One begins to wonder why providers are reluctant to use capnography.  The patient suffered anoxic brain damage while undergoing vertebral facet joint injection in a prone position under sedation. Capnography, if used during this case, could have alerted sedation providers of hypoventilation and impending hypoxia. Dr Kaye describes this case as one of more than 100 cases, he is asked to review. Clinicians seem to make same mistakes of inadequate monitoring over and over again and nothings seems to change the attitude of clinicians. 


Read the following (April 12, Anesthesiology News)

 A common mistake seems to be a lack of appreciation among clinicians that a patient could easily drift from conscious sedation to unconscious state, which is literally general anesthesia.  This transition resulting in hypoventilation and apnea is not recognized due to lack of monitoring using continuous capnography. 


Dr Kaye makes the following critical points to educate and alert clinicians to the value of capnography during sedation 


“The issue is that in many of these cases, the clinicians believe pulse oximetry is enough,” Kaye explained. “Well, we know that’s not the case. By the time the pulse oximeter drops, the patient has usually not been breathing for four or five minutes. “That’s why end-tidal CO2 has been an ASA monitoring requirement since 2010,” he continued. “So why are people not using it? 

“If a patient is not ventilating, a standard end-tidal CO2 alarm will go off in 20 or 30 seconds, depending on the brand of monitor. Do you think anyone would die or have brain damage, or their heart would stop or they would need to be coded? No, absolutely not.

“By using quantitative end-tidal CO2, under any of these situations, the odds of a patient having a bad outcome would decrease to virtually nothing,” Kaye said. “It is singularly the most important way to protect patients, and that’s why it’s one of the ASA standard monitors required for sedation and general anesthesia.”

A 2017 study agreed (BMC Anesthesiol 2017;17[1]:157). In that investigation, a pair of researchers analyzed the Premier Database to determine the effect of capnography monitoring on the incidence of adverse outcomes and death following gastrointestinal endoscopic procedures. The study involved 258,262 medical inpatients and 3,807,151 outpatients who were grouped according to the type of monitoring: pulse oximetry only, capnography only, pulse oximetry with capnography, and neither pulse oximetry nor capnography. The analysis found that among inpatients, capnography monitoring was associated with a 47% estimated reduction in the odds of death at discharge (odds ratio [OR], 0.53; P<0.0001). Among outpatients, capnography monitoring was associated with a 61% estimated reduction in the odds of a pharmacologic rescue event at discharge (OR, 0.39; P<0.0001) and an 82% estimated reduction in the odds of death at discharge (OR, 0.18; P=0.16)

Dr. Kaye summarizes that the following steps are required to prevent catastrophic outcomes during sedation.

“First of all, clinicians need to realize that in most cases, they don’t need propofol, primarily because patients don’t need deep sedation or general anesthesia for most of these day procedures,”.

“Second, every single patient must be monitored with quantitative, continuous end-tidal CO2, with no exceptions. Finally, if anesthesiologists are going to bill for monitored anesthesia care, they’d better make sure they’re actually fulfilling all of the TEFRA 7 requirements.” Documentation of work performed is key.

With this simple recipe, Kaye sees no reason why needless death and disability must continue to occur. “These are real things that are going on, but they should never go on. We should be leading on this critically important topic of safe sedation.”