I was looking through ASC Becker Review and came across this eyecatching headline: "Study: Propofol Colonoscopies May Result In Aspiration Pneumonia". Really? That sounds pretty extreme and scary. The study in question comes from JAMA Internal Medicine titled "Complications following Colonoscopy With Anesthesia Assistance". It is written by Gregory Cooper, M.D., a gastroenterologist from Case Western Reserve University, Tzuyung Kou, PhD., and Douglas Rex, M.D., a well known critic of anesthesiologists in the GI suite. The provenance of this article pretty much sets the tone for the paper.
In the study, Dr. Cooper took a 5% sampling of all the diagnostic colonoscopies without polypectomies that were billed to Medicare between 2000 and 2009. Therefore all the patients are over 65 years old. They found over 165,000 colonoscopies performed during that period on over 100,000 patients. Just over 21% of the cases were given anesthesia. They then looked at the incidence of aspiration, splenic injuries, and colon perforation.
To no one's surprise, they found that patients given anesthesia had a 40% greater chance of suffering an aspiration compared to those who only received moderate sedation. This sounds terrifying until you read the actual numbers. Out of 165,000 colonoscopies, only 173 patients aspirated. Breaking it down further, 0.14% of anesthetized patients aspirated vs. 0.10% of nonanesthetized patients. They estimate that this difference in aspiration risks would have resulted in an extra 518 cases of aspiration in 2009 alone. That is out of millions of colonoscopies that are done in this country every year.
They acknowledge that one problem with this study is that there is no way to compensate for different risk levels in the patients. This is not a randomized double blind study. We don't know what the ASA levels of the patients are that received anesthesia or moderate sedation. To compensate the authors studied a subset of patients that only received their colonoscopies in ambulatory surgery centers, out of the hospital setting where the patients are presumed to be sicker. Here, there appeared to be slightly more complications with the anesthetized group but this did not achieve statistical significance.
Dr. Cooper's study also looked into the relative risks of splenic injuries and colon perforations from colonoscopies. Their presumption is that patients under anesthesia have less pain sensation during the procedure so there should be a higher risk for these devastating complications. Perhaps to their disappointment there was no difference between the anesthetized and sedated patients in developing these injuries.
So what does this study tell us? Contrary to the attention grabbing headline, not much at all. Sure they showed that slightly more patients developed an aspiration when anesthetized during a colonscopy. But this number is so small relative to the total number of procedures that it is almost negligible. When I am discussing risks of anesthesia with a patient, I certainly don't feel obligated to bring up a complication that may occur 0.14% of the time. Especially in this elderly group, they are more likely to suffer a cardiac event than an aspiration. This study also couldn't take into account the different risk levels of patients. When they tried to look only at what are thought to be healthier patients in surgery centers, they found no difference in complication rates. Therefore the higher complications of anesthetized patients overall most likely occurred in hospitalized patients, who presumably are sicker and have more comorbidities. That's usually the main reason anesthesiologists are utilized in the GI suite, for sicker patients. Therefore they are more likely to have adverse outcomes like an aspiration. Then there is their disingenuous attempt to pin the gastroenterologist induced complications of splenic and colon injuries on anesthesia which here showed no such correlation. How lame is that?
When all else fails, bring up the issue of money. The authors casually mention that having an anesthesiologist in the GI suite increases costs by 20%. What I don't understand is the GI docs' obsession with saving money when it comes to discussions about anesthesia. In the meantime they are unnecessarily scoping every Tom, Dick, and Mary in the hospital with a pulse. If a patient derives greater comfort during a procedure with anesthesia, why not let them have it? Anesthesia is considered one of the greatest inventions of modern medicine. Obstetricians decades ago recognized that having a comfortable patient provides better well being and better outcome. Sure women having been giving birth since the dawn of time without the aid of anesthesia. But isn't the world a better place because we can give them that comfort? The cost of providing epidurals is never considered frivolous or wasteful. Why shouldn't giving comfort to a GI patient be considered equally humane?
Let's also not forget the peace of mind we provide for our GI colleagues. As this study shows, aspirations and perforations can happen whether the patients received anesthesia or not. I bet those GI docs who have a patient who aspirated wished to God that an anesthesiologist was there to take the blame, er I mean protect the airway. Perhaps all these reasons are why the authors noted that colonoscopies are increasingly being performed with an anesthesia provider in the room. The extra costs are minimal compared to the comfort and reassurance we can provide the patient and the endoscopist. It is an act of humanity that should not be denied based on dollars and cents.