Capnography and patient safety for endoscopy

Machine-Learning Model for the Prediction of Hypoxaemia during Endoscopic Retrograde Cholangiopancreatography under Monitored Anaesthesia Care

PURPOSE

Hypoxaemia is a significant adverse event during endoscopic retrograde cholangiopancreatography (ERCP) under monitored anaesthesia care (MAC); however, no model has been developed to predict hypoxaemia. We aimed to develop and compare logistic regression (LR) and machine learning (ML) models to predict hypoxaemia during ERCP under MAC.

MATERIALS AND METHODS

We collected patient data from our institutional ERCP database. The study population was randomly divided into training and test sets (7:3). Models were fit to training data and evaluated on unseen test data. The training set was further split into k-fold (k=5) for tuning hyperparameters, such as feature selection and early stopping. Models were trained over k loops; the i-th fold was set aside as a validation set in the i-th loop. Model performance was measured using area under the curve (AUC).

RESULTS

We identified 6114 cases of ERCP under MAC, with a total hypoxaemia rate of 5.9%. The LR model was established by combining eight variables and had a test AUC of 0.693. The ML and LR models were evaluated on 30 independent data splits. The average test AUC for LR was 0.7230, which improved to 0.7336 by adding eight more variables with an l₁ regularisation-based selection technique and ensembling the LRs and gradient boosting algorithm (GBM). The high-risk group was discriminated using the GBM ensemble model, with a sensitivity and specificity of 63.6% and 72.2%, respectively.

CONCLUSION

We established GBM ensemble model and LR model for risk prediction, which demonstrated good potential for preventing hypoxaemia during ERCP under MAC.

Pre-procedural Preparation and Sedation for Gastrointestinal Endoscopy in Patients with Advanced Liver Disease

Gastrointestinal endoscopy in patients with advanced liver disease poses various challenges, a major one being procedural sedation and its associated considerations. While sedation during endoscopy can improve patient comfort, decrease anxiety, and facilitate procedural completion, in patients with advanced liver disease, it is also associated with substantial and unique risks due to alterations in drug metabolism and other factors. As such, the choice of sedative agent(s) and related logistics may require careful inter-disciplinary planning and individualized considerations. Furthermore, a large proportion of agents require dose reductions and particular monitoring of the vital signs, level of consciousness, and other indices. In the present review, we provide a contemporary overview of procedural sedation considerations, commonly used intravenous sedatives, and second-line as well as novel sedatives for gastrointestinal endoscopy in patients with advanced liver disease.

Efficacy and Safety of Deep Sedation and Anaesthesia for Complex Endoscopic Procedures—A Narrative Review

Propofol sedation for advanced endoscopic procedures is a widespread technique at present, which generates controversy worldwide when anaesthetic or non-anaesthetic personnel administer this form of sedation. There is some evidence for safe administered propofol sedation by non-anaesthetic personnel in patients undergoing endoscopy procedures, but there are only few randomised trials addressing the safety and efficacy of propofol in patients undergoing advanced procedures. A serious possible consequence of propofol sedation is the rapid and unpredictable progression from deep sedation to general anaesthesia mostly when elderly and frail patients are involved in the diagnosis or treatment of various neoplasia. This situation requires rescue measures with skilled airway management. The aim of this paper is to review the safety and efficacy aspects of sedation techniques, with special reference to propofol administration covering the whole patient journey, including preassessment, sedation options and discharge when advanced endoscopic procedures are performed.

Benefits and harms of capnography during procedures involving moderate sedation: A rapid review and meta-analysis

BACKGROUND

Patient safety is a priority in dentistry. Evaluating the benefits and harms associated with the addition of capnography to standard monitoring during moderate sedation for adult patients in the dental practice setting is needed.

TYPES OF STUDIES REVIEWED

The authors used rapid review methodology to identify relevant systematic reviews, which they updated through a systematic search by using the same search strategy as the identified reviews. The authors searched PubMed and Google Scholar and through the references of the identified systematic reviews, which yielded 2,892 studies. Inclusion criteria were that the article was available in English, was original research in adult humans who had undergone moderate procedural sedation, and involved comparing standard monitoring with the addition of capnography.

RESULTS

Sixteen studies were eligible, involving 3,866 adults undergoing procedural sedation. The authors used the Grading of Recommendations Assessment, Development and Evaluation approach to evaluate the evidence and rate it as being of moderate to low quality because of high risk of bias and heterogeneous effects for the outcomes of hypoxemia and adverse respiratory events. Capnography had higher sensitivity to detect adverse respiratory events than did standard monitoring alone (0.92; 95% confidence interval, 0.65 to 0.99) and may reduce the risk of developing hypoxemia by 31% (risk ratio, 0.69; 95% confidence interval, 0.57 to 0.82). Capnography did not affect the risk of developing serious adverse events, procedure time, sedation quality, or patient satisfaction.

CONCLUSIONS AND PRACTICAL IMPLICATIONS

Adding capnography to standard monitoring of adults during moderate sedation may reduce the risk of developing hypoxemia, increase detection of adverse respiratory events, and is not associated with additional harms. These findings suggest routine use of capnography during moderate sedation has the potential to reduce adverse anesthetic outcomes in dental practice.

Capnographic monitoring reduces the incidence of arterial oxygen desaturation and hypoxemia during propofol sedation for colonoscopy: a randomized, controlled study (ColoCap Study)

OBJECTIVES

The aim of this randomized study was to determine whether intervention based on additional capnographic monitoring reduces the incidence of arterial oxygen desaturation during propofol sedation for colonoscopy.

METHODS

Patients (American Society of Anesthesiologists classification (ASA) 1-3) scheduled for colonoscopy under propofol sedation were randomly assigned to either a control arm with standard monitoring (standard arm) or an interventional arm in which additional capnographic monitoring (capnography arm) was available. In both study arms, detection of apnea or altered respiration induced withholding propofol administration, stimulation of the patient, chin lift maneuver, or further measures. The primary study end point was the incidence of arterial oxygen desaturation (defined as a fall in oxygen saturation (SaO(2)) of ≥5% or <90%); secondary end points included the occurrences of hypoxemia (SaO(2) <90%), severe hypoxemia (SaO(2) ≤85%), bradycardia, hypotension, and the quality of sedation (patient cooperation and patient satisfaction).

RESULTS

A total of 760 patients were enrolled at three German endoscopy centers. The intention-to-treat analysis revealed a significant reduction of the incidence of oxygen desaturation in the capnography arm in comparison with the standard arm (38.9% vs. 53.2%; P<0.001). The numbers of patients with a fall in SaO(2) <90% and ≤85% were also significantly different (12.5% vs. 19.8%; P=0.008 and 3.7 vs. 7.8%; P=0.018). There were no differences regarding the rates of bradycardia and hypotension. Quality of sedation was similar in both groups. Results of statistical analyses were maintained for the per-protocol population.

CONCLUSIONS

Additional capnographic monitoring of ventilatory activity reduces the incidence of oxygen desaturation and hypoxemia during propofol sedation for colonoscopy.

Safe and effective procedural sedation for gastrointestinal endoscopy in children

OBJECTIVE

The aim of the study was to assess, by a review of published evidence, the safest and most effective way to provide procedural sedation (PS) in children undergoing gastrointestinal endoscopy (GIE).

METHODS

The databases MEDLINE, Cochrane Library, and Embase were used. Search terms "endoscopy, gastrointestinal" or "endoscopy, digestive system" were combined with "sedation," "conscious sedation," "moderate sedation," "deep sedation," and "hypnotics and sedatives." The final review was restricted to studies reporting specifically on safety (incidences of adverse events) and/or effectiveness (time characteristics, need for supplemental sedation, need for restraint, procedural success, provider satisfaction, and patient comfort) of PS for GIE in children younger than 18 years.

RESULTS

The search yielded 182 references and the final selection included 11 randomized controlled trials (RCTs) and 15 non-RCTs. Six sedation categories were identified: propofol, opioid/benzodiazepine, premedication, ketamine-, sevoflurane-, and midazolam-based. Only a few RCTs have compared different categories. Opioid/benzodiazepine- and propofol-based PS have a similar safety profile and a low incidence of major adverse events. Propofol-based sedation turned out to be the most effective regimen, with effectiveness comparable to general anesthesia. The addition of midazolam, fentanyl, remifentanil, and/or ketamine to propofol may increase the effectiveness without creating more adverse events. Data on midazolam-, ketamine- and sevoflurane-based sedation were generally too limited to draw conclusions.

CONCLUSIONS

Despite a lack of RCTs containing all aspects of effectiveness and safety, the present evidence indicates propofol-based PS to be the best practice for PS in children undergoing GIE. Propofol can be safely administered by specifically trained nonanesthesiologists.