A movement toward patient autonomy has rightfully received increased attention from the medical community over the last 30 years. We’ve moved from an era of paternalism to an era of patient-centered outcomes and shared decision-making. Although both philosophies, at their extremes, are likely harmful, there exists a balance somewhere in the middle that is appropriate for the knowledge imbalance inherent in medical care. In this quarters JOBIP, authors Grossmann et al1 have placed the amnestic power of propofol in the hands of patients undergoing bronchoscopy and compare this strategy to a control group receiving nursing administered midazolam.
Patient-controlled analgesia (PCA) plays a large role in postoperative pain control and PCA delivered opiates have been shown to improve pain control and increase patient satisfaction.2 However, patient-controlled sedation (PCS) with propofol during endoscopic procedures is a conceptual shift. Propofol’s unique pharmacology, including a narrow therapeutic window and short half-life, make it an attractive medication for PCS as self-induced sedation would limit additional administration of propofol. Although there is little evidence for this strategy during bronchoscopy, this approach to sedation has been safely tested during colonoscopy and endoscopic retrograde cholangiopancreatography (ERCP) with success. During a colonoscopy, Külling et al3 found that PCS with propofol and alfentanil was equivalent in terms of procedural success and comfort to continuous infusion of propofol and alfentanil or nurse administered meperidine and midazolam, although the PCS group had less hypercarbia and less hypotension and faster recovery.3 In a second trail, Ng et al4 compared propofol PCS with a set bolus anesthesiologist administered midazolam. One outcome measured by Ng and colleagues was the percent of patients ready for discharge 30 minutes after the procedure and Ng and colleagues found a higher percentage of the patient were ready for discharge at 30 minutes in the propofol PCS group than in the control midazolam group. PCS with propofol has also been tested during ERCP in 2 trials, which is important because ERCP may be more similar in duration and discomfort to advanced bronchoscopy than routine colonoscopy. One trial tested the efficacy of target-controlled infusion of propofol with patient-controlled bolus dosing. This small trial showed target-controlled infusion was safe and effective with high satisfaction scores by endoscopists and patients.5 A larger trial randomized 80 patients to PCS with propofol and remifentanil versus anesthesiologist administered propofol with fentanyl.6 Overall success was high with both strategies in terms of successful completion of the procedure and patient and endoscopic satisfaction were high in both groups, however, the overall level of patient sedation was lower in the PCS group. In addition, patients in the PCS group recovered more rapidly when sedation scores were measured 30 minutes postprocedure.
The study published by Grossmann and colleagues in JOBIP this quarter tests the efficacy of PCS with propofol during a mix of basic and advanced bronchoscopic procedures, including staging endobronchial ultrasound. Many might worry about the safety of this approach, however, the safety of PCS with propofol in this well-conducted randomized controlled trial was slightly better than then control group and actually required fewer overnight hospitalizations. Furthermore, the primary outcome, which was the percentage of patients ready for discharge 2 hours after the procedure, was significantly higher in the PCS group versus the standard anesthesia of premedication with morphine-scopolamine and then nursing administered midazolam during the procedure. A second aim of the study was to test the efficacy of pretreatment with either morphine-scopolamine versus glycopyrrolate in the PCS group. The glycopyrrolate group self-administered more propofol during the procedure, but 96% of patients were ready for discharge 2 hours after the procedure while only 65% in the morphine-scopolamine group were ready for discharge at the same timepoint, suggesting if any pretreatment is utilized, then glycopyrrolate might be superior. However, the authors question the use of any pretreatment and suggest propofol monotherapy may be reasonable. Drawbacks of this study, which the authors appropriately point out, include the lack of blinding of bronchoscopists and anesthesia staff as well as inadequate power to detect differences in key safety endpoints.
Sedation for advanced bronchoscopic procedures, including endobronchial ultrasound and electromagnetic navigation can be especially challenging because these procedures are intermittently intensely stimulating (during the biopsy or when wedging the scope) and can end abruptly when a diagnosis is made. As procedural volumes increase, preoperative and postoperative areas can become bottlenecks for patient flow and thus rapid postprocedural recovery is an important area for investigation. In addition, more effective sedation strategies may prove to be more cost-effective.7 Although there may be some regulatory hurdles for US providers, this model of anesthetic patient autonomy which decreases the time to discharge deserves attention and further study in larger multicenter randomized trials.
1. Grossmann B, Nilsson A, Sjöberg F, et al. Patient-controlled sedation during flexible bronchoscopy: a randomized controlled trial. J Bronchology Interv Pulmonol. 2020. [Epub ahead of print].
2. Hudcova J, McNicol E, Quah C, et al. Patient controlled opioid analgesia versus conventional opioid analgesia for postoperative pain. Cochrane Database Syst Rev. 2006;4:CD003348.
3. Külling D, Fantin AC, Biro P, et al. Safer colonoscopy with patient-controlled analgesia and sedation with propofol and alfentanil. Gastrointest Endosc. 2001;54:1–7.
4. Ng JM, Kong CF, Nyam D. Patient-controlled sedation with propofol for colonoscopy. Gastrointest Endosc. 2001;54:8–13.
5. Gillham MJ, Hutchinson RC, Carter R, et al. Patient-maintained sedation for ERCP with a target-controlled infusion of propofol: a pilot study. Gastrointest Endosc. 2001;54:14–17.
6. Mazanikov M, Udd M, Kylänpää L, et al. Patient-controlled sedation with propofol and remifentanil for ERCP: a randomized, controlled study. Gastrointest Endosc. 2011;73:260–266.
7. Grossmann B, Nilsson A, Sjöberg F, et al. Patient-controlled sedation with propofol for endoscopic procedures—a cost analysis. Acta Anaesthesiol Scand. 2020;64:53–62.