Nonanesthesiologist administration of propofol: it’s all about money

Propofol is tending to replace so-called traditional sedation (i. e., benzodiazepine with or without opioids), particularly during colonoscopy, because of its advantages for both the patient and the endoscopist [1] [2]. For example, between 2003 and 2007 in the USA, the involvement of anesthesiologists in colonoscopy almost tripled, from 9 % to 25 % of colonoscopies, and this figure is projected to exceed 50 % by 2015 [3]. The additional cost of indiscriminate anesthesiologist involvement in colonoscopy is a serious concern. This is particularly true when the purpose of colonoscopy is to screen for colorectal cancer because a test used for screening the general population must be cost-effective. For example, in France, fecal testing has been chosen for colorectal cancer screening because it is the most cost-effective method [4]; in that country, 90 % of colonoscopies are performed with sedation and intravenous sedation of any type may only be administered by anesthesiologists (!). Anesthesiologist involvement adds 285 % to the cost of a colonoscopy (EUR 740 vs. EUR 192, respectively, for a colonoscopy with vs. without an anesthesiologist) [4]. Nonanesthesiologist administration of propofol (NAAP) retains the advantages of propofol-based sedation while maintaining patient safety and lowering costs [1] [2]. Obstacles to implementation of NAAP, whether at a national level or at the level of the endoscopy unit, mostly come down to costs and to relationships between endoscopists and anesthesiologists. Costs include NAAP training and, possibly, additional staff; these are not usually offset by increased income as in many countries there is no additional reimbursement for sedation performed by nonanesthesiologists. Relationships between endoscopists and anesthesiologists (at a personal or a national society level) may be strongly influenced by financial considerations as endoscopic sedation is usually easy and may be very lucrative for anesthesiologists.

In this issue of Endoscopy, Hassan et al. provide objective data to support a shift in the attitude of policymakers in favor of NAAP and its reimbursement [5]. The authors calculated the costs related to NAAP implementation at a national level for a screening colonoscopy program in the USA: propofol administration by nurses rather than by anesthesiologists for screening colonoscopy would result in savings of 3.2 billion USD over a 10-year period. Their calculations assumed 28.3 million screening colonoscopies in 10 years, including 9.8 million colonoscopies (34.8 %) with propofol-based sedation. This would translate into savings per colonoscopy of 326.5 USD (3.2 billion/9.8 million). One of the authors’ assumptions was that the cost of NAAP would be limited to nurse training for a two-week period (this aspect of the study was clarified by personal communication with the authors). This means that the nurse assisting the endoscopist with ancillary tasks during colonoscopy, such as polypectomy, would at the same time administer propofol and monitor the patient. This option corresponds to the practice of a significant minority of endoscopists who perform NAAP (one third of endoscopists in a recent international survey) [6]. However, guidelines issued by the American Society of Gastrointestinal Endoscopy (ASGE) and the European Societies of Gastrointestinal Endoscopy, of Gastroenterology and Endoscopy Nurses and Associates, and of Anaesthesiology (ESGE, ESGENA, and ESA) recommend that a trained person be dedicated to the uninterrupted monitoring of the patient’s clinical and physiologic parameters throughout the procedure performed under NAAP [1] [2] [7]. This guideline requirement for an additional person dedicated exclusively to patient sedation was prompted by safety concerns and it is specific to NAAP; for traditional sedation, it is recommended that “the registered nurse may perform minor, interruptible tasks (e. g., biopsy or polypectomy)” [8]. Interestingly, Hassan et al. assumed for their calculations that no mortality would be related to propofol sedation, and they showed in a sensitivity analysis that NAAP remained cost-effective with a sedation-related mortality rate corresponding to that reported in the largest study published on this topic (which included procedures more risky than colonoscopy) [9].

The ESGE – ESGENA – ESA recommendation for an additional person dedicated exclusively to NAAP during endoscopic sedation carries a cost and there is no specific reimbursement for this service in most countries. Despite criticism [10], this requirement was maintained in our recommendation due to the lack of high quality studies showing the safety of NAAP without a person dedicated to that task [11]. Arguably, Hassan et al. are correct to point out that colonoscopy is likely the least risky endoscopic procedure performed with NAAP [9].

The next challenge for the endoscopic community would be the establishment of large training programs for NAAP. This would not be an easy task, because of the large number of nurses to be trained (17 166 for the USA according to the calculations of Hassan et al.) and the ESGE – ESGENA – ESA Guideline recommendation that the first 30 NAAP procedures should be done with a tutor [1] [2]. Organization would be crucial for completion of such a training in two weeks as assumed by the authors. Currently, the largest national training program for NAAP is in Germany where more than 5000 nurses have been trained so far with the help of anesthesiologists; similar programs are being developed in Denmark and Switzerland. In Germany, incidentally, no fee is reserved for anesthesiologists who perform sedation during endoscopy, confirming that in many countries financial concerns are a major motivation of anesthesiologists who attempt to hinder the implementation of NAAP.

Emerging options for NAAP allow both the lowering of costs and the alleviation of medicolegal concerns; these modalities include administration of propofol-based sedation by patients themselves (patient-controlled sedation, PCS) or by a computer that monitors the patient (“computer-assisted personalized sedation,” e. g. the Sedasys system, Ethicon Endo-Surgery, Cincinnati, Ohio, USA) [13] [14].

In its simplest form, PCS is similar to patient-controlled analgesia: patients are instructed to press the button of a pump whenever they wish to receive a dose of propofol (mixed or not with a short-acting opioid, depending on protocols). Interaction with the endoscopist may be helpful because the endoscopist can warn the patient of painful phases of the examination, so limiting sedation to a minimum if the patient wishes. More than 10 randomized controlled trials (RCTs) have compared PCS using propofol with other sedation modalities during colonoscopy; they have shown that, compared with traditional sedation, PCS provides inferior pain control but higher patient satisfaction and similar complication rates [15]. The discordance between pain control and patient satisfaction likely reflects the fact that patients appreciate being able to decide their appropriate sedation level. Among these RCTs, five have compared propofol-based sedation administered via PCS or by a healthcare professional [12] [16] [17] [18] [19]. Of note, 39 % of the 561 patients who were eligible for randomization in these RCTs refused inclusion, in many cases because they did not want to take the responsibility for their own sedation [18]. Significant differences found in these five RCTs between propofol-based sedation administered by PCS compared with by a healthcare professional may be summarized as follows: with PCS, there were fewer cardiorespiratory events (three RCTs; P values of 0.052, 0.05 and 0.007) [13] [17] [19], there were lower drug doses (two RCTs) [13] [17], higher patient satisfaction (one RCT) [16], and higher patient willingness to repeat the examination [13]. It is amusing – but logical – to note that in the three RCTs that showed fewer cardiorespiratory events with PCS compared with controls, sedation in the control group was administered by an anesthesiologist [13] [17] [19], while in the two RCTs that found no difference in cardiorespiratory events, sedation in the control group was administered by a nurse [16] [18]. In the present author’s experience, colonoscopy with PCS may take a few minutes more than with standard NAAP if the endoscopist interrupts endoscope insertion during latency periods (from patient awakening to their pressing the button to the drug’s taking effect). The patients included in these five RCTs were categorized as American Society of Anesthesiologists (ASA) physical status class up to III, except in the oldest RCT, published in 2001, which was restricted to ASA classes I and II [16].

Computer-assisted personalized sedation is a more recent alternative to standard NAAP than PCS: drug administration is adjusted by a computer that uses feedback from a real-time measure of drug effect (e. g., patient reaction to computer-generated voice and tactile stimuli, or using a bispectral index); the oxygen flow rate may also be automatically adjusted if the pulse oximetry measure drops below a predetermined value [12]. One of these systems has recently been shown in a large multicenter RCT to be safe and effective for administering propofol during routine colonoscopy in ASA I – III patients [12].

Whatever the particular modality of NAAP, patient triage and personnel training are crucial to the successful implementation of this technique. Even the training of a single nurse in an endoscopy unit may improve global patient comfort and safety at minimal cost because it adds a further option to the triage scheme of no sedation vs. traditional sedation vs. anesthesiology care. NAAP is best used in relatively fit patients for whom an endoscopic procedure of relatively low complexity is expected, reserving expert anesthesiology resources to more difficult cases. Hassan et al. have shown that the savings expected from such a training largely outweigh investment costs, particularly if NAAP is administered by a nurse who is not dedicated exclusively to patient sedation. This modality of NAAP is not yet officially supported by endoscopy societies but innovative alternatives to this modality of NAAP do exist. They will likely contribute to an appropriate fulfilment of the legitimate desire of patients for adequate sedation during endoscopy.

• References

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