Abstract:
Objectives: In the Endoscopy Department at the Roudebush Veterans Administration (VA) Medical Center, procedural sedation is primarily given by the nursing staff at the direction of a Gastroenterologist. However, approximately 25% of the patients, determined to be tolerant of the sedation provided by the nurses, are scheduled to receive Monitored Anesthesia Care (MAC) given by the Anesthesia Department. Recently, there has been an increased demand for MAC sedation in the health care sector for the general population (Adams et al., 2017). In 2013, there was 47.6% and 53% increase use of MAC sedation for Medicare and privately insured patients, respectively (Predmore, Nie, Main, Mattke & Liu, 2017). The use of MAC sedation in the Veterans Health Administration has more than doubled, from 4% in 2000 to 9.3% in 2013 (Adams et al., 2017).
The factors that are associated with sedation tolerance are not clearly defined. Patients are scheduled to receive MAC sedation if they have an active opioid prescription, severe or unstable disease burden, or a prior history of failed nurse sedation. However, there is a lack of consensus on the precise criteria that should be used to determine if MAC sedation is required (Alharbi et al., 2009). Professional associations supporting American Gastroenterologists agree that MAC sedation is not required for average-risk patients and should be reserved for high-risk patients (Aisenberg, Brill, Ladabaum & Cohen, 2005). While studies have examined the factors associated with tolerance to nurse sedation, no studies have been done in the veteran population. In addition, of the studies that examined the impact various factors had on sedation requirements, the effect cannabis use had on sedation requirements was not analyzed.
Research Design: A study into the factors associated with sedation requirements will be undertaken, with chronic cannabis use as the specific focus of this scholarly project. A retrospective analysis of all elective EGD and colonoscopy procedures for 2013-2017 will be performed. Patients with documented cannabis use will be analyzed to identify if cannabis use was associated with sedation tolerance. Cannabis use combined with the use of prescription psychoactive medications will also be evaluated. Cannabis use is highly associated with psychiatric disorders (Bonn-Miller, Harris & Trafton, 2012). The goal is to develop evidenced-based criteria to identify the patients who would most likely require MAC sedation.
Clinical Significance: The goal is to develop evidenced-based criteria to identify the patients who would most likely require MAC sedation. There is little in the research that examines the interaction between cannabis and anesthetic medications. The effects of chronic cannabis use on anesthesia need to be clearly investigated. A retrospective analysis of the effects of cannabis on sedation requirements will fill the gaps that exist in the literature. If the studies are correct and cannabis has potent analgesic properties, does that translate to tolerance to the sedation medications commonly administered by nurses for elective endoscopy procedures?
There is an association between anxiety and the use of cannabis. Bonn-Miller and Rousseau (2017) found an increased risk of a cannabis use disorder (CUD) in veterans with PTSD. Bonn-Miller et al. (2012) examined the rates of PTSD and CUD and found that the rates of PTSD and CUD both increased from 2002-2007. The percentage of veterans with a CUD that also had a psychiatric diagnosis was 70% (Bonn-Miller et al., 2012). Loflin et al. (2017) reported that for veterans who use cananbis, those that defined their cananbis use as medicinal (rather than recreational) had more symptoms of arousal when cued about experiences during combat. The link between CUD and a psychiatric illness is strong but not diagnostic. However, the presence of a CUD should alert the healthcare provider that a mental illness may also exist.
Impact: There are factors that increase sedation requirements, according to some researchers, including opioid use, benzodiazepine use, an alcohol use disorder, and pre-procedural anxiety. The scholarly project plans to determine if cannabis use increases sedation requirements for elective endoscopic procedures. This will enable the Endoscopy Department and the Anesthesia Department to efficiently schedule patients who are at risk for failed nurse sedation with MAC sedation.