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 Table of Contents  
Year : 2019  |  Volume : 8  |  Issue : 4  |  Page : 102-106

Propofol administration by anesthesiologists versus endoscopists during colonoscopy: Does it make a difference?

1 Dubai Colorectal and Digestive Clinic, Dubai, United Arab Emirates
2 Department of Anesthesia, Al-Zahra Hospital Dubai, United Arab Emirates
3 Department of Gastroenterology, Al-Zahra Hospital Dubai, United Arab Emirates
4 Department of Endoscopy Unit, Emirates Specialty Hospital, Dubai, United Arab Emirates

Date of Submission27-Sep-2019
Date of Decision18-Oct-2019
Date of Acceptance09-Nov-2019
Date of Web Publication27-Dec-2019

Correspondence Address:
Dr. Maher A Abbas
Dubai Colorectal and Digestive Clinic, Dubai
United Arab Emirates
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Source of Support: None, Conflict of Interest: None

DOI: 10.4103/WJCS.WJCS_23_19

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Background: Propofol anesthesia for endoscopic procedures has gained wide acceptance among physicians and patients. Much debate remains though whether propofol can be safely administered by non-anesthesiologists. Objective: To compare the procedural outcome of patients undergoing colonoscopy with Propofol target-controlled infusion administered by anesthesiologists vs. non-anesthesiologists. Design: A retrospective review. Setting: A private community hospital in Dubai, United Arab Emirates. Patients and Methods: All consecutive patients (age > 13 years, with American Society of Anesthesiologists class I-II and no other contraindications to administration of sedation by non-anesthesiologists) who underwent colonoscopy between January 1, 2017 and September 30, 2017. In the initial part of the study, propofol was administered by an anesthesiologist until the endoscopists were trained to provide propofol anesthesia via targeted-controlled infusion [TCI] by syringe pump. Intraprocedural data was collected in a prospective registry. Statistical analysis was performed using Chi square and student t test. Main Outcome Measures: Cecal intubation rate, procedural time, procedural-related complications, and polypectomy/biopsy rate. Sample Size: 347 patients. Results: Group 1 [anesthesiologists] 84 patients, Group 2 [endoscopists] 263 patients. Mean age was 44.8 and 46.9 years in Group 1 and 2, respectively (P = 0.17). There was no difference in gender distribution. The mean procedural time was 21 minutes in both groups (P = 0.93). The cecal intubation rate was similar [92.9% in Group 1 vs. 94.3% in Group 2, P = 0.40). No difference in procedural-related complications was noted between groups, with 1 patient in Group 2 sustaining endoscopic perforation during balloon dilation of a near obstructing anastomotic stricture. Except for the patient with endoscopic perforation, no patient required advanced airway management. Conclusions: Propofol can be safely administered by endoscopists using target-controlled infusion. Similar total procedural time and cecal intubation rate can be achieved without increased risk of procedural-related complications. Limitations: Retrospective review, community-based hospital, elective cases, small cohort size. Conflict of Interest: None.

Keywords: Anesthesiologists, colonoscopy, endoscopists, propofol sedation, surgeons

How to cite this article:
Abbas MA, Shalabi M, Gopalan D, Bianzon P, Georgopoulos F. Propofol administration by anesthesiologists versus endoscopists during colonoscopy: Does it make a difference?. World J Colorectal Surg 2019;8:102-6

How to cite this URL:
Abbas MA, Shalabi M, Gopalan D, Bianzon P, Georgopoulos F. Propofol administration by anesthesiologists versus endoscopists during colonoscopy: Does it make a difference?. World J Colorectal Surg [serial online] 2019 [cited 2020 Apr 9];8:102-6. Available from: http://www.wjcs.us.com/text.asp?2019/8/4/102/274286

  Introduction Top

The introduction of colonoscopy in the 1960s revolutionized the practice of medicine and advanced the care of patients with gastrointestinal (GI) disorders.[1] The ability to inspect the colon with a flexible endoscope provided a new platform for diagnostic purposes and improved the physicians' ability to provide an accurate diagnosis. Further development of endoscopic tools, such as biopsy forceps and snares, transformed colonoscopy from a diagnostic tool into a therapeutic one.[2],[3] The ability to visualize the colonic mucosa, identify and biopsy an abnormal growth, and, in some cases, completely remove a polyp generated intense interest in the use of colonoscopy as a screening tool for colorectal cancer, which is one of the leading causes of cancer-related deaths globally.[4],[5] The identification of adenomatous polyps and early-stage colorectal cancer with colonoscopy provided an opportunity to prevent cancer or eradicate it at an earlier curable stage.[6],[7] Over the last few decades, the volume of colonoscopy has steadily grown with an estimated 15 million procedures performed in the United States in 2012.[8]

As the endoscopic technology has evolved and improved over the last four decades, there has been a gradual shift from the technical feasibility of colonoscopy to the quality of the procedure, safety, and patient care experience.[9],[10],[11] From the patient's perspective, common concerns revolve around the difficulty with bowel preparation and pain control during the procedure.[12],[13] Providing adequate sedation and pain control during the procedure is an important component of a positive patient care experience. In the last decade, there has been an increasing interest in propofol sedation for patients undergoing colonoscopy. Studies have demonstrated that propofol sedation offers better patient care experience, an increase in the endoscopist's satisfaction, and improved workflow efficiency in the endoscopy suite.[14],[15],[16] The use of propofol in the endoscopy suite is on the rise. Traditionally, the administration of this drug was limited to the practice of the specialty of anesthesia. The use of propofol by nonanesthesiologists has gained acceptance in a few European countries. In the United States, the debate continues whether such clinical practice should be supported.[17]

The purpose of this study was to compare the procedural outcome of patients undergoing colonoscopy with propofol sedation using target-controlled infusion (TCI) administered by anesthesiologists vs nonanesthesiologists.

  Patients and Methods Top

A retrospective review was conducted of all consecutive patients who underwent outpatient colonoscopy in a private community hospital (Al-Zahra Hospital, Dubai, United Arab Emirates) between January 1, 2017 and September 30, 2017. The hospital chief of staff in charge of the medical staff approved the study. All patients underwent oral mechanical bowel preparation at home and presented to the outpatient endoscopy suite after fasting for 6 hours. This review excluded patients belonging to the American Society of Anesthesiologists (ASA) class 3 and above, pediatric patients less than 13 years of age, patients with difficult airways or sleep apnea, and emergency cases. Propofol sedation (Profol 10 mg/ml, Dongkook Pharmaceutical, Choong Cheong Book-Do, South Korea) was introduced into the endoscopy suite in 2015 and initially administered by anesthesiologists as repeated bolus injections. Eventually, all anesthesiologists at our hospital converted their method of propofol administration to propofol sedation using TCI (Injectomat Agilio TIVA®, Fresenius Kabi, Brézins, France) [Figure 1]. TCI is a computer-assisted drug infusion system that provides a safe and more predictable pharmacokinetics-based plasma level or effector site level of propofol. In most patients, in addition to the propofol, a fentanyl bolus injection (Fentanyl citrate 0.05 mg/ml, Janssen-Cilag, Macquarie Park, Australia) ranging between 50 and 100 μg was administered.
Figure 1: Target-controlled infusion syringe pump (Injectomat Agilio TIVA®, Fresenius Kabi, Brézins, France)

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In 2017, a collaborative decision was made to train the endoscopists and endoscopy nurses at our hospital to administer propofol sedation using TCI. The training included theoretical knowledge in the form of lectures and practical skills as a hands-on course. This training was followed by an examination with multiple-choice questions to obtain the clinical privilege for propofol administration. All endoscopists and endoscopy nurses were certified for advanced cardiac life support (ACLS). Before starting to administer propofol sedation using TCI for ASA class I-II patients, six endoscopists were initially coached and observed by an anesthesiologist for five to ten cases each. When the endoscopists directed propofol administration, the TCI system was managed by an endoscopy nurse who loaded the computer device with a propofol syringe and selected the Marsh or the Schneider pharmacokinetic model. The parameters entered into the device were the patient's age, weight (in addition to the Schneider protocol gender and height), and the target in plasma or effector site according to the pharmacokinetic model used. For most patients, the initial target rate was between 2.0 and 4.0 μg/ml. During the procedure, the patient's vital signs were monitored using basic standard monitoring with the help of pulse oximetry, noninvasive blood pressure (BP) measurement, continuous electrocardiography, and capnography. One nurse managed the TCI system along with other medications and intravenous (IV) fluids while another nurse was responsible for monitoring the vital signs, administering supplemental oxygen by nasal cannula or facemask, and ensuring a patent airway. One additional nurse assisted the endoscopist with biopsies and specimen collection as needed. The propofol infusion was stopped when the endoscopists reached the rectosigmoid during the withdrawal phase. The patients were woken up in the endoscopy suite and transferred to the recovery area from where they were routinely discharged within 1 hour of the procedure.

The data were collected prospectively by the endoscopy charge nurse and entered into an Excel Sheet (Microsoft, Washington, USA). The collected parameters included patient demographics and procedure-related data, such as polypectomy/biopsy rate, cecal intubation rate, mean procedural time, airway complications, cardiovascular events, and procedure-related complications. Statistical analysis was performed using Chi-square and student t-test. The criterion for statistical significance was P < 0.05. All analyses were performed using the Statistical Package for the Social Sciences (SPSS) software, version 15.1 (SPSS Inc, Chicago, Illinois).

  Results Top

During the study period, 347 patients underwent colonoscopy with propofol sedation using TCI. Group 1 (propofol sedation administered by anesthesiologists) consisted of 84 patients and Group 2 (propofol sedation directed by endoscopists) had 263 patients. [Table 1] summarizes the study findings.
Table 1: Patient demographics and intraprocedural outcome

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The mean age was 44.8 and 46.9 years in Group 1 and 2, respectively (P = 0.17). There was no difference in gender distribution. The mean procedural time was 21 min in both groups (P = 0.93). The biopsy/polypectomy rate was similar in both groups. No difference in cecal intubation rate was noted between the two groups (92.9% in Group 1 and 94.3% in Group 2, P = 0.40). There was no difference in procedure-related complications in both groups, with one patient in Group 2 sustaining endoscopic perforation during balloon dilation of an obstructing anastomotic stricture. Except for the patient with endoscopic perforation, no patient required advanced airway management in either group. No cardiovascular event or instability was noted in either group. Beyond the endoscopy suite, no readmission or complications, such as bleeding or perforation, were noted.

  Discussion Top

Over the last several decades, colonoscopy has become an essential component of the diagnostic and therapeutic procedures available to diagnose and treat patients with colorectal conditions. In the United States alone, over 15 million procedures are performed annually. With the potential future implementation of comprehensive national colorectal cancer-screening programs, several million additional colonoscopies could be performed annually.[8] Good pain control and adequate sedation during the procedure are of paramount importance to ensure a positive patient care experience to gain acceptance of the procedure and compliance with the recommendation to undergo colonoscopy. Propofol sedation during colonoscopy has emerged as the preferred method of sedation.[14],[15] In some countries, an endoscopist directing the propofol administration during colonoscopy has become an accepted practice;[17] however, in the United States whether this practice should be allowed is open to debate. The focus of this debate includes a range of issues involving economic and financial factors, regulatory matters, and medico-legal concerns. To resolve these issues in a constructive way, the focus of the debate should be on the clinical care of the patient, specifically the quality and safety of the care. Our study was performed to examine the intraprocedural outcomes when propofol sedation using TCI was administered by anesthesiologists vs non-anesthesiologists. It was found that endoscopists were able to safely administer propofol sedation using TCI. No difference was noted in procedural time, cecal intubation rate, and procedure- or sedation-related complications.

The findings of this study are important for several reasons. First, they demonstrated that a collaborative approach between the anesthesiologists and endoscopists that is focused on patient care issues is feasible in the private nonacademic sector. Second, a brief proctoring period involving 5 to 10 cases was sufficient for the safe implementation of propofol sedation by the endoscopists. Third, the introduction of TCI into the endoscopy suite of a private community hospital allowed for the rapid implementation of this program, giving the endoscopists the opportunity to focus on performing the procedure safely. Under the direction of the endoscopists, the endoscopy nurses managed the TCI machine throughout the procedure. However, it is important to point out the few limitations of this study. It was a retrospective review of prospectively collected limited data set that was aimed at ensuring safety and quality. The study was limited to patients with ASA class I-II who underwent colonoscopy on outpatient basis. Thus, the findings cannot be generalized to sicker patients with higher level of comorbidities, patients with sleep apnea or difficult airways, or those in the inpatient setting with emergencies. The nature of the practice setting of a private, community-based hospital is focused on the provision of clinical care; hence, a more extensive research study with more comprehensive data set was not feasible. No patient surveys were collected to compare the patient experience with the process based on whether anesthesiologists or endoscopists administered the propofol anesthesia. However, we speculate that the patient care experience would be similar as the technique was standardized by TCI, and the individual verbal feedback from the patients was positive in both groups. Finally, it is important to point out that major safety events are uncommon; thus, despite providing data on 347 patients, a much larger number of patients would have been needed to reach firm conclusions.

Regardless of whether anesthesiologists or nonanesthesiologists administer procedural sedation, one of the main challenges has been the wide fluctuations in plasma drug levels seen with repeated bolus infusions. Such practice leads to periods of oversedation when administering the bolus and periods of under sedation when the blood concentration of propofol falls over time until a further bolus is needed. Oversedation, with its detrimental cardiopulmonary consequences, and under sedation, with its negative impact on pain control and awareness of the patient, are well-known undesired events. By using TCI, the plasma level or effector site level of propofol remains constant all the time, thus, minimizing the incidence of both of these undesired events.

The findings of our study add to an increasing body of literature supporting the use of propofol sedation using TCI during colonoscopy by nonanesthesiologists. Ferreira et al. conducted a single-blinded, noninferiority, randomized controlled trial (RCT) comparing propofol sedation by endoscopists and anesthesiologists.[18] Two hundred and seventy-seven patients with ASA class I-II were studied. No difference in adverse events was noted between groups and there was no sentinel adverse events in either group. Minor interventions included atropine administration, airway repositioning, increased oxygen administration, and increased fluid rate. No difference was noted in mean propofol dose, withdrawal time, patient satisfaction, and amnesia. Another RCT was conducted by Molina-Infante et al. to evaluate the feasibility of moderate sedation by nonanesthesiologists.[19] Two medication regimens administered by nonanesthesiologists were compared in a double-blinded, randomized, placebo-controlled trial. Placebo with propofol infusion was compared with midazolam injection with propofol infusion. The mean induction and total propofol doses were higher in the placebo group. However, deep sedation and longer early recovery were noted in the patients who received midazolam—although that group of patients had better pain perception and satisfaction scores. No major complications were noted in either group.

Propofol sedation using TCI is delivered using a computer-assisted drug infusion. This technology aims to achieve an endoscopist-defined target concentration at the Ce stands for Effect-site concentration (Ce) based on patient-related parameters, such as age, gender, weight, and height. It is important to note that TCI is the product of several decades of global research that required extensive pharmacokinetic studies and the evolution of several generations of infusion pumps.[20],[21] The advantages of TCI is to provide a more scientific approach to anesthesia and sedation based on pharmacokinetics, establishing a steady state of drug delivery without overdosing the patient, and eliminating the wide fluctuations in plasma level seen with repeated bolus administration. These advantages translate into a more reliable and safer administration of anesthesia and sedation. TCI adds another layer of safety and standardization of propofol sedation administration during colonoscopy. With the evolving experience of endoscopists with propofol and introduction of the TCI machines, we believe that such standard of practice (SoP) should be more widely supported and implemented. Such practice has been previously endorsed by the European Society of Gastrointestinal Endoscopy (ESGE) and the European Society of Gastroenterology and Endoscopy Nurses and Associates (ESGENA).[22] In 2018, the American Society for Gastrointestinal Endoscopy (ASGE) SoP committee published their guidelines for sedation and anesthesia in GI endoscopy and suggested the use of propofol-based sedation as an acceptable practice whether endoscopist directed or anesthesiologist administered (personnel administering propofol should have expertise in emergency airway management).[23] These guidelines were endorsed by the American College of Gastroenterology (ACG), the American Gastroenterological Association (AGA), and the American Association for the Study of Liver Diseases (AASLD).

  Conclusion Top

The modern delivery of health care is a complex endeavor with various aspects encompassing clinical care, quality, safety, economics, policymaking, regulatory matters, and medico-legal issues. However, safe, efficient, and patient-centered care should remain the central focus of health care delivery and policymaking. Practice guidelines related to propofol sedation for a colonoscopy, one of the most common procedures in modern medicine, should be guided by a collaborative effort aimed at doing what is best for the patients. This study revealed that such a collaborative effort is feasible in the private community hospital setting. The purpose of this study was to demonstrate that for a select group of ASA class I-II healthy patients, undergoing outpatient procedures, propofol sedation using TCI by nonanesthesiologists can be safely provided after a brief proctorship process of five to ten procedures. A higher level of anesthesia expertise and the involvement of anesthesiologists remains a necessity for sicker patients and those undergoing emergency procedures.


We would like to acknowledge our nursing team that has supported the implementation of the propofol sedation with TCI and made this research project feasible: Leilani Acuna, RN; Hina Akber, RN; Albert Bengay, RN; Browyn Eisma, RN; Ancy George, RN; Kency Kunjumon, RN; John Paul Lalugan, RN; and Reenamol Sebastian, RN.

Delivered as a podium presentation at the American Society of Colon and Rectal Surgeons 2018 Annual Meeting, Nashville, Tennessee, USA, May 19–23, 2018.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.

  References Top

Wolff WI. Colonoscopy: History and development. Am J Gastroenterol 1989;84:1017-25.  Back to cited text no. 1
Wolff WI, Shinya H. Polypectomy via the fiberoptic colonoscope. Removal of neoplasms beyond reach of the sigmoidoscope. N Engl J Med 1973;288:329-32.  Back to cited text no. 2
Sivak MV. Polypectomy: Looking back. Gastrointest Endosc 2004;60:977-82.  Back to cited text no. 3
Siegel RL, Miller KD, Fedewa SA, Ahnen DJ, Meester RG, Barzi A, et al. Colorectal cancer statistics, 2017. CA Cancer J Clin 2017;67:177-93.  Back to cited text no. 4
Bhandari A, Woodhouse M, Gupta S. Colorectal cancer is a leading cause of cancer incidence and mortality among adults younger than 50 years in the USA: A SEER-based analysis with comparison to other young-onset cancers. J Investig Med 2017;65:311-5.  Back to cited text no. 5
Zauber AG, Winawer SJ, O'Brien MJ, Lansdorp-Vogelaar I, van Ballegooijen M, Hankey BF, et al. Colonoscopic polypectomy and long-term prevention of colorectal-cancer deaths. N Engl J Med 2012;366:687-96.  Back to cited text no. 6
Brenner H, Stock C, Hoffmeister M. Effect of screening sigmoidoscopy and screening colonoscopy on colorectal cancer incidence and mortality: Systematic review and meta-analysis of randomized controlled trials and observational studies. BMJ 2014;348:g2467.  Back to cited text no. 7
Joseph DA, Meester RG, Zauber AG, Manninen DL, Winges L, Dong FB, et al. Colorectal cancer screening: Estimated future colonoscopy need and current volume and capacity. Cancer 2016;122:2479-86.  Back to cited text no. 8
Gavin DR, Valori RM, Anderson JT, Donnelly MT, Williams JG, Swarbrick ET. The national colonoscopy audit: A nationwide assessment of the quality and safety of colonoscopy in the UK. Gut 2013;62:242-9.  Back to cited text no. 9
Rutter MD, Senore C, Bisschops R, Domagk D, Valori R, Kaminski MF, et al. The European Society of Gastrointestinal Endoscopy Quality Improvement Initiative: Developing performance measures. Endoscopy 2016;48:81-9.  Back to cited text no. 10
Calderwood AH, Jacobson BC. Colonoscopy quality: Metrics and implementation. Gastroenterol Clin North Am 2013;42:599-618.  Back to cited text no. 11
McLachlan SA, Clements A, Austoker J. Patients'experiences and reported barriers to colonoscopy in the screening context—A systematic review of the literature. Patient Educ Couns 2012;86:137-46.  Back to cited text no. 12
Basch CH, Basch CE, Zybert P, Wolf RL. Fear as a barrier to asymptomatic colonoscopy screening in an urban minority population with health insurance. J Community Health 2016;41:818-24.  Back to cited text no. 13
Padmanabhan A, Frangopoulos C, Shaffer LE. Patient satisfaction with Propofol for outpatient colonoscopy: A prospective, randomized, double-blind study. Dis Colon Rectum 2017;60:1102-8.  Back to cited text no. 14
Riphaus A, Macias-Gomez C, Devière J, Dumonceau JM. Propofol, the preferred sedation for screening colonoscopy, is underused. Results of an international survey. Dig Liver Dis 2012;44:389-92.  Back to cited text no. 15
Vicari JJ. Sedation in the ambulatory endoscopy center: Optimizing safety, expectations, and throughput. Gastrointest Endosc Clin N Am 2016;26:539-52.  Back to cited text no. 16
Rex DK. Endoscopist-directed propofol. Gastrointesti Endosc Clin N Am 2016;26:485-92.  Back to cited text no. 17
Ferreira AO, Torres J, Barjas E, Nunes J, Glória L, Ferreira R, et al. Non-anesthesiologist administration of Propofol sedation for colonoscopy is safe in low risk patients: Results of a noninferiority randomized controlled trial. Endoscopy 2016;48:747-53.  Back to cited text no. 18
Molina-Infante J, Dueñas-Sadornil C, Mateos-Rodriguez JM, Perez-Gallardo B, Vinagre-Rodríguez G, Hernandez-Alonso M, et al. Nonanesthesiologist-administered Propofol versus midazolam and Propofol, titrated to moderate sedation, for colonoscopy: A randomized controlled trial. Dig Dis Sci 2012;57:2385-93.  Back to cited text no. 19
Absalom AR, Glen JB, Zwart GJ, Schnider TW, Struys MM. Target-controlled infusion: A mature technology. Anesth Analg 2016;122:70-8.  Back to cited text no. 20
Schnider TW, Minto CF, Struys MM, Absalom AR. The safety of target-controlled infusions. Anesth Analg 2016;122:79-85.  Back to cited text no. 21
Dumonceau JM, Riphaus A, Schreiber F, Vilmann P, Beilenhoff U, Aparicio JR, et al. Non-anesthesiologist administration of Propofol for gastrointestinal endoscopy: European Society of Gastrointestinal Endoscopy, European Society of Gastroenterology and Endoscopy Nurses and Associates Guideline – Updated June 2015. Endoscopy 2015;47:1175-89.  Back to cited text no. 22
ASGE Standards of Practice Committee, Early DS, Lightdale JR, Vargo JJ 2nd, Acosta RD, Chandrasekhara V, et al. Guidelines for sedation and anesthesia in GI endoscopy. Gastrointest Endosc 2018;87:327-37.  Back to cited text no. 23


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