Procedure Areas

Should Physician Assistants and Nurse Practitioners Perform Colonoscopy?

As I prepared to write this post and discussed it with my colleagues, there were only two responses: this is a great idea and this is a horrible idea. When it comes to abdicating physician clinical responsibilities to advance practice providers, there just is no more polarizing topic in medicine. And the performance of colonoscopy is the most polarizing of the polarizing.

30 years ago, non-surgical procedures were the realm of the physician. As a resident, I was trained in and expected to be able to perform bone marrow biopsies, central venous catheters, endotracheal intubation, flexible sigmoidoscopy, lumbar punctures, and paracenteses. But these procedures have largely disappeared from the portfolio of today’s residency training programs and are now frequently relegated to non-physician practitioners. Recently, our medical center rolled out a bedside procedure team staffed by nurse practitioners who perform central line placement, thoracentesis, lumbar puncture, and paracentesis. Nurse practitioners do nearly all of the bone marrow biopsies in our hospital. Across the country, nurse midwives perform deliveries, respiratory therapists do endotracheal intubation, and physician assistants place dialysis catheters. One of the last bastions of physician-performed procedures is the screening colonoscopy. But should colonoscopy go the way of central lines and bone marrow biopsies? This was the subject of a recent pro and con article in AGA Perspectives publication of the American Gastroenterological Association.

How Many Screening Colonoscopies Need To Be Done Each Year?

Colon cancer occurs in 4.4% of American men and 4.1% of American women. One-third of people who get colon cancer will die of it. Most colon cancers arise from colon polyps and it takes about 10 years for a polyp to turn into a cancer. 30% of American men and 20% of American women will develop a colon polyp at some time during their lives. Screening colonoscopy can identify colon polyps before they turn into cancer and allow for removal of the polyp, thus preventing colon cancer. The current recommendations are for every American to have screening colonoscopy every 10 years from age 50 through age 75. If a polyp is found, then screening should be increased to every 5 years. If a person has a first-degree relative with colon cancer, then screening should start at age 40 and occur every 5 years. When you do the math it works out that:

  1. The average low-risk American should get 3 colonoscopies during a lifetime (66% of Americans).
  2. The average American with a polyp should get 6 colonoscopies during a lifetime (22% of Americans).
  3. The average American with a family history of colon cancer should get 8 colonoscopies during a lifetime (12% of Americans)

Doing additional math, overall, the average American should get 4.3 colonoscopies during a lifetime. Based on the age demographics from the 2016 U.S. Census, on any given year, 4,235,000 Americans should be getting their first colonoscopy and 17,881,000 Americans should be getting a follow-up colonoscopy. Adding these numbers up, if we were to optimally screen every American for colon cancer, we would need to do a total of 22 million screening colonoscopies every year.

Screening colonoscopy is primarily done by gastroenterologists and general surgeons. Currently in the United States, there are 14,000 gastroenterologists and 25,000 general surgeons. If all screening colonoscopy was done by gastroenterologists, then the average gastroenterologist would need to do 1,571 screening colonoscopies per year to completely cover the needs. If screening colonoscopy is done by both gastroenterologists and general surgeons, then they would need to do 637 per year on average. In reality, these numbers are way over-inflated because there will always be Americans who adamantly refuse to undergo colonoscopy, those who wait 11 years rather than 10 years between regular screening colonoscopies, those who are uninsured, and those who don’t undergo colonoscopy because it is pointless if they are dying of some other disease. The current estimate of the actual numbers in the United States are 14 million screening colonoscopies and 3 million screening flexible sigmoidoscopes.

Medicare alone currently spends $1.8 billion per year on outpatient colonoscopies ($416 million just on professional fees). However, since the majority of screening colonoscopies would be done in patients under age 65 (and thus not covered by Medicare), private insurance companies in the United States pay even more than this.

Are We Meeting All Of The Country’s Needs For Screening Colonoscopy?

If all that a gastroenterologist did was screening colonoscopy, then the demands could be easily covered. However, gastroenterologists (and general surgeons) do far more than just screening colonoscopy. They do endoscopy and colonoscopy for purposes other than screening for colon cancer, they do consults, and they do longitudinal management of patients with gastrointestinal diseases.

The economic law of supply and demand predicts that gastroenterologists will migrate to where screening colonoscopy is highly lucrative. A diagnostic colonoscopy is worth 3.26 work RVUs which equates to about $114 for Medicare. Medicaid will pay considerably less, about $70. The Congressional Budget Office estimates that the average commercial insurance plan pays about 1.75 times more than Medicare for colonoscopy, or about $200 for the physician work component. So, in suburban areas serving patients with commercial insurance, there should be plenty of gastroenterologists to cover the demand for screening colonoscopy whereas in an urban area serving patients with Medicaid, there will likely be insufficient gastroenterologists to cover the demands. The same will be true for rural areas and Veterans Hospitals. So, even if we have enough gastroenterologists (and general surgeons) to meet the overall screening colonoscopy needs in the United States, there will inevitably be geographic pockets of unmet needs that will not be supplied by gastroenterologists (and general surgeons).

Can These Areas Of Unmet Colon Cancer Screening Needs Be Met By Non-Gastroenterologists (And General Surgeons)?

The 2018 Medscape Physician Compensation Report indicates that the average gastroenterologist makes $408,000 per year and the average general surgeon makes $322,000 per year. In comparison, the average physician assistant makes $105,000, the average nurse practitioner makes $107,000 per year and the average nurse anesthetists makes about $169,000 per year. There is not enough data to know what the salary of an NP/PA colonoscopist would make but it is probably in between the average NP/PA and a nurse anesthetists, say about $135,000 per year. Therefore, combining the compensation for the professional services portion of a diagnostic colonoscopy with the average salaries we can determine the number of diagnostic colonoscopies it would take to cover salary (benefits not included).

The next part of this question is whether or not non-physicians can competently perform screening colonoscopy. A meta-analysis from 2014 that pooled results of 24 studies found that polyp detection rates, colon cancer diagnosis rates, and complication rates were similar between nurse practitioner/physician assistants and physicians.

How Many Colonoscopies During Training Are Needed To Achieve Proficiency?

The current recommendations for gastroenterologist training is to do a minimum of 275 supervised colonoscopies. However, one study in 2010 suggested that optimal competency requires 500 supervised colonoscopies; a more recent study in 2016 confirmed the 500 procedure per trainee number. Other studies found competency could be reached after 250 or 275 procedures. The problem with many of these studies is the they did not separate purely screening colonoscopy from colonoscopy with interventions (such as polypectomy). Different professional societies have different recommendations for the number of procedures performed under supervision in order to get hospital privileges.

  1. American Academy of Family Physicians: 50 colonoscopies
  2. American Board of Surgery: 50 colonoscopies
  3. American Society for Gastrointestinal Endoscopy: 275 colonoscopies

So, should your hospital train and utilize physician assistants and nurse practitioners to do colonoscopy?

The answer is probably no if:

  1. The hospital is in a location dominated by patients covered by commercial health insurance
  2. There is currently enough credentialed physicians to meet colonoscopy demand in a timely fashion
  3. There is not a wait time for non-procedural services by the gastroenterologists (outpatient consults, etc.)
  4. There is not an unmet need for surgical services by general surgeons

The answer may be yes if:

  1. The hospital largely cares for a large number of Medicaid and Medicare patients
  2. It is a Veterans Administration hospital
  3. There is a long wait time for screening colonoscopy
  4. There is a long wait time for gastroenterologist consultation because the gastroenterologists are spending too much time in the endoscopy suite
  5. Patients cannot get their hernias repaired and their gall bladders removed because the general surgeons are spending too much time in the endoscopy suite.

What Would I Do If I Was Making Up The Rules?

First, a minimum number of supervised colonoscopies during training would need to be established. Using the ASGE recommendations, this would likely be 275. To win over skeptics, it may need to be as many as 500. A training program for physician assistants or nurse practitioners would be costly because of the additional time required by the gastroenterologist (or general surgeon) to supervise a trainee doing a procedure versus the shorter time it would take himself or herself to do the procedure. Furthermore, it is unlikely that many NPs or PAs would do this time of training for free so there would be the cost of paying their salary during the training period. It would likely take about 3-4 months of fairly intensive, full-time procedural training to achieve the minimum of 275 screening colonoscopies. Once you factor in didactic teaching, non-procedural disease management, and training in other procedures (such as paracentesis), then the entire training program would probably be about a year.

Second, a decision would need to be made about whether the NP or PA will be permitted to do polypectomy unsupervised. If the answer is no, then there would need to be a gastroenterologist (or general surgeon) immediately available in the endoscopy suite who could step in to perform or supervise polypectomy. The only way to make this financially viable would be to have one physician available to two or three NPs or PAs simultaneously.

Third, there would have to be up-front negotiation with payers about reimbursement for screening colonoscopies performed by NPs or PAs. For example, if there is a physician present in the endoscopy suite, can the colonoscopy be billed as “incident to” service or would it be reimbursed as an NP/PA independent service (which generally pays 15% less)?

Fourth, there will need to be a decision made about upper endoscopy. For example, should an NP/PA be able to do routine screening upper endoscopy for patients with Barrett’s esophagus?

What Would My Ideal Program Look Like?

  1. I would start off by having 3 trained NPs or PAs doing screening colonoscopies with a gastroenterologist (or general surgeon) present in the endoscopy suite for polypectomies, complication management, or diagnostic questions. Statistically, at any given time, 1 of the 3 NP/PAs will be doing a colonoscopy that will require the physician’s presence.
  2. I would create a monitoring office where the video feeds from all 3 individual procedure rooms could be fed into monitors so that the supervising physician could periodically check the progress and findings of the procedures.
  3. The NP/PAs would also be trained and credentialed in paracentesis so that they could also be doing those time-intensive paracenteses that gastroenterologists do not want to do.
  4. I would create a hospital-paid position of “Director of Endoscopy Training” to provide financial support for the time a gastroenterologist (or general surgeon) spends supervising the 275 screening colonoscopies that the NP/PA in training requires.
  5. I would make it financially lucrative for the gastroenterologist (or general surgeon) to supervise the 3 NP/PAs by splitting the work RVUs with the physician in a way that makes supervising screening colonoscopy more attractive than performing it solo themself.
  6. During the time that the NP/PAs are not doing colonoscopy, I would have them follow up biopsy results, arrange patient follow-up, complete procedure notes, see inpatient consult follow-ups and, see outpatient return office visits.
  7. I would create a peer-review process whereby the recorded videos of the colonoscopy withdrawal by the NP/PA would be reviewed by another of the NP/PAs so that each NP/PA would have 25 procedures reviewed per year for quality purposes.
  8. Eventually, I would create a pathway for the NP/PAs to be able to perform polypectomies independently. Because I would anticipate a considerable amount of skepticism about a non-physician colonoscopy program, I would phase in polypectomy a few years after the initial screening colonoscopy program with the requirement that the NP/PAs perform some minimal number of supervised polypectomies (for example, 150).

Probably the biggest barrier will be the professional threat that gastroenterologists may feel to having a non-physician do colonoscopy. For most gastroenterologists, colonoscopy is an integral part of their core identity as a specialist. They take pride in their art and skill of colonoscopy and take pride in the number of lives they save by colon cancers prevented. However, medicine is increasingly requiring a team approach and it may be time for us to consider screening colonoscopy as a team sport rather than as an individual sport.

May 4, 2019

By James Allen, MD

I am a Professor Emeritus of Internal Medicine at the Ohio State University and former Medical Director of Ohio State University East Hospital