Nasal oxygen alleviates hypoxemia in colonoscopy patients sedated with midazolam and meperidine

2021 Korean Society of Gastrointestinal Endoscopy Clinical Practice Guidelines for Endoscopic Sedation

Sedation can resolve anxiety and fear in patients undergoing endoscopy. The use of sedatives has increased in Korea. Appropriate sedation is a state in which the patient feels subjectively comfortable while maintaining the airway reflex for stable spontaneous breathing. The patient should maintain a state of consciousness to the extent that he or she can cooperate with the needs of the medical staff. Despite its benefits, endoscopic sedation has been associated with cardiopulmonary complications. Such cardiopulmonary complications are usually temporary, and most patients recover without sequelae. However, these events may progress to serious complications, such as cardiovascular collapse. Therefore, it is essential to screen high-risk patients before sedation and reduce complications by meticulous monitoring. Additionally, physicians should be familiar with the management of emergencies. The first Korean clinical practice guideline for endoscopic sedation was developed based on previous worldwide guidelines for endoscopic sedation using an adaptation process. The guideline consists of nine recommendations based on a critical review of currently available data and expert consensus when the guideline was drafted. These guidelines should provide clinicians, nurses, medical school students, and policy makers with information on how to perform endoscopic sedation with minimal risk.

[2021 Korean Society of Gastrointestinal Endoscopy Clinical Practice Guidelines for Endoscopic Sedation]

Sedation can resolve anxiety and fear in patients undergoing endoscopy. The use of sedatives has increased in Korea. Appropriate sedation is a state in which the patient feels subjectively comfortable while maintaining the airway reflex for stable spontaneous breathing. The patient should maintain a state of consciousness to the extent that he or she can cooperate with the needs of the medical staff. Despite its benefits, endoscopic sedation has been associated with cardiopulmonary complications. Cardiopulmonary complications are usually temporary. Most patients recover without sequelae. However, they may progress to serious complications, such as cardiovascular collapse. Therefore, it is essential to screen high-risk patients before sedation and reduce complications by meticulous monitoring. Additionally, physicians should be familiar with the management of emergencies. The first Korean clinical practice guideline for endoscopic sedation was developed based on previous worldwide guidelines for endoscopic sedation using an adaptation process. The guideline consists of nine recommendations based on a critical review of currently available data and expert consensus when the guideline was drafted. These guidelines should provide clinicians, nurses, medical school students, and policy makers with information on how to perform endoscopic sedation with minimal risk.

2021 Korean Society of Gastrointestinal Endoscopy Clinical Practice Guidelines for Endoscopic Sedation

Sedation can resolve anxiety and fear in patients undergoing endoscopy. The use of sedatives has increased in Korea. Appropriate sedation is a state in which the patient feels subjectively comfortable while maintaining the airway reflex for stable spontaneous breathing. The patient should maintain a state of consciousness to the extent that he or she can cooperate with the needs of the medical staff. Despite its benefits, endoscopic sedation has been associated with cardiopulmonary complications. Cardiopulmonary complications are usually temporary. Most patients recover without sequelae. However, they may progress to serious complications, such as cardiovascular collapse. Therefore, it is essential to screen high-risk patients before sedation and reduce complications by meticulous monitoring. Additionally, physicians should be familiar with the management of emergencies. The first Korean clinical practice guideline for endoscopic sedation was developed based on previous worldwide guidelines for endoscopic sedation using an adaptation process. The guideline consists of nine recommendations based on a critical review of currently available data and expert consensus when the guideline was drafted. These guidelines should provide clinicians, nurses, medical school students, and policy makers with information on how to perform endoscopic sedation with minimal risk.

Oxygenation before Endoscopic Sedation Reduces the Hypoxic Event during Endoscopy in Elderly Patients: A Randomized Controlled Trial

Background: Sedation endoscopy increases patient and examiner satisfaction but involves complications. The most serious complication is hypoxia, the risk factors for which are old age, obesity, and American Society of Anesthesiologists physical status of 3 or greater. However, clear evidence of oxygenation during sedation endoscopy for elderly people is lacking in US, European, and Korean guidelines. Method: This study was conducted for 1 year starting in August 2018 to evaluate whether pre-oxygenation use 1 min before sedation endoscopy could reduce the incidence of hypoxia in patients older than 65 years of age. A total of 70 patients were divided into the non-oxygenated group (n = 35; control group) and oxygen-treated group (n = 35; experimental group) during endoscopy. Result: The incidence of hypoxia was 28 (80%) in the control group versus 0 (0%) in the pre-oxygenated group. Factors related to hypoxia in the non-oxygenated group were a relatively high dose of midazolam and concomitant injection with narcotic analgesics such as pethidine. Conclusion: The incidence of hypoxia during sedation endoscopy is high in patients over 65 years, but oxygenation during endoscopic sedation in elderly people can significantly reduce the incidence of intraprocedural hypoxic events.

Practice Guidelines for Moderate Procedural Sedation and Analgesia 2018

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European Society of Gastrointestinal Endoscopy, European Society of Gastroenterology and Endoscopy Nurses and Associates, and the European Society of Anaesthesiology Guideline: Non-anaesthesiologist administration of propofol for GI endoscopy

Propofol sedation by non-anaesthesiologists is an upcoming sedation regimen in several countries throughout Europe. Numerous studies have shown the efficacy and safety of this sedation regimen in gastrointestinal endoscopy. Nevertheless, this issue remains highly controversial. The aim of this evidence- and consensus-based set of guideline is to provide non-anaesthesiologists with a comprehensive framework for propofol sedation during digestive endoscopy. This guideline results from a collaborative effort from representatives of the European Society of Gastrointestinal Endoscopy (ESGE), the European Society of Gastroenterology and Endoscopy Nurses and Associates (ESGENA) and the European Society of Anaesthesiology (ESA). These three societies have endorsed the present guideline.The guideline is published simultaneously in the Journals Endoscopy and European Journal of Anaesthesiology.

Pain relief for reduction of acute anterior shoulder dislocations: a prospective randomized study comparing intravenous sedation with intra-articular lidocaine

OBJECTIVES

The aim was to compare the effectiveness of intra-articular lidocaine (IAL) versus intravenous Demerol and Diazepam (IVS) in reduction of acute anterior shoulder dislocation.

DESIGN

This is a prospective randomized study.

SETTING

Emergency room setting.

PATIENTS

Thirty-one dislocations reduced with IVS, whereas 32 patients were reduced using IAL.

MAIN OUTCOME MEASUREMENTS

The visual analog pain scale was used before analgesic administration and during the closed manipulative reduction. Length of time since dislocation, frequency of dislocation, ease of reduction, patient satisfaction, adverse effects, and duration of hospitalization were recorded.

RESULTS

The IVS group had a 100% success rate, whereas the IAL group had a 19% (six of 32) failure rate (P = 0.024). However, there was no significant difference in terms of pain relief (P = 0.23) or patient satisfaction (P = 0.085) between both groups. In addition, patients in the IAL group had a shorter duration of hospitalization and no reported complications, whereas the intravenous group had a longer hospital stay and a 29% complication rate. The cost of IAL was 32% less than the cost for IVS.

CONCLUSION

IAL was more cost effective than the IVS method. IAL provided adequate pain relief and fewer complications and is a viable option for analgesia during reduction of acute shoulder dislocation.

Assessment the effect of midazolam sedation on hypoxia during upper gastrointestinal endoscopy

The aim of this study was to evaluate the prevalence of hypoxia related to midazolam sedation during upper gastrointestinal endoscopy. This single blind randomized placebo control clinical trial, carried out on 180 patients who referred to endoscopy clinic at Imam Khomeini Hospital for selective upper gastrointestinal endoscopy from April to July in 2008. Informed consents obtained from all participants. Patients under 18-years-old, obese, previous history of asthma, COPD and cigarette smoking were excluded. Arterial hemoglobin saturation controlled by finger probe pulse oximetry. After pharyngeal lidocaine spray, midazolam was administered intravenously in case group and patients in controlled group received placebo. Demographic characteristics and other variables were recorded in a questionnaire and data analyzed using SPSS software. Gastrointestinal disturbances and epigastric pain were major indications of endoscopies. The most common endoscopic diagnoses were deudonitis, esophagitis or gastroesophagial reflux. No patients had any serious episode of hypoxia and the incidence of mild hypoxia was not significant in both studied group (p = 0.823). There was no significant difference in arterial oxygen saturation recorded by the three endoscopists (p = 0.734). Our data showed that optimal dose of sedation had no hypoxia. So that, we recommend sedative endoscopy in patients without risk factors for hypoxia.

Comparison of safety and efficacy of ERCP performed with the patient in supine and prone positions

BACKGROUND

ERCP is usually performed with the patient in the prone position. Little data exist on ERCP in the supine position, which is considered unsafe in nonintubated patients.

OBJECTIVE

Our purpose was to compare outcomes of ERCP in the prone and supine positions.

DESIGN

Retrospective study.

SETTING

Tertiary care medical center.

PATIENTS

All patients undergoing ERCP by one endoscopist over an 18-month period.

MAIN OUTCOME MEASUREMENTS

American Society of Anesthesiologists (ASA) score, procedural degree of difficulty, procedural time, success rates, complication rates, effects on oxygen desaturation and hemodynamics, amount of sedation, need for precut sphincterotomy.

RESULTS

A total of 649 patients were evaluated, of whom 506 patients were prone and 143 were supine. There were no differences between the groups with regard to sex, procedural time, ASA scores, need for precut sphincterotomy, adverse cardiovascular events, episodes of oxygen desaturation, dose of meperidine or midazolam, or oxygen supplementation. Complete success and complication rates were similar for both groups (90.2% and 11.2% for supine and 92.5% and 9.1% for prone, respectively). Procedural degree of difficulty was significantly higher in the supine group (P < .001). There were no episodes of aspiration in either group and no severe complications.

LIMITATIONS

Retrospective study, one endoscopist.

CONCLUSIONS

ERCP performed in nonintubated patients placed supine is often more difficult and may lead to more mild adverse respiratory events than when performed with the patient prone. Supine ERCP is appropriate in certain patients who cannot lie prone (abdominal pain, abdominal distention, ascites, recent abdominal or neck surgery, indwelling percutaneous tubes and need for access during the procedure to indwelling internal/external percutaneous biliary catheters, and in the morbidly obese) with more intensive monitoring in those who are not intubated.

Has the pendulum swung too far in postoperative pain control?

BACKGROUND

The Joint Commission on Accreditation of Health Care Organizations declared pain level to be the "fifth vital sign." This has led to increased efforts to reduce patients' pain scores. Current postoperative analgesic modalities may not be entirely safe. We prospectively studied pain and sedation scores to determine whether postoperative patients were reaching sedation levels similar to patients undergoing "conscious sedation" (eg, colonoscopy cases). "Conscious sedation" patients have been shown to achieve states of sedation, which at time result in oxygen desaturation.

METHODS

Fifty-three patients within three groups were compared in an observational study. Group 1 included "conscious sedation" patients undergoing colonoscopy. Group 2 included postoperative patients using patient-controlled analgesia (PCA). Group 3 included postoperative patients under nurse-controlled analgesia (NCA). Levels of sedation were monitored using the 6-point Ramsay sedation scale. Pain and oxygen saturation were monitored using an 11-point verbal scale and finger pulse oximetry, respectively. Patients were monitored for up to 12 hours in the postoperative period or for the length of their colonoscopy procedure.

RESULTS

Patients in groups 1 and 2 reached similar sedation levels.

CONCLUSIONS

Patients may reach dangerous levels of sedation during the first 24 hours postoperatively. Patients using PCA devices warrant close observation during this time period.

Conscious sedation and cardiorespiratory safety during colonoscopy

BACKGROUND

Cardiorespiratory events during colonoscopy are common. The effect of sedative premedication on cardiorespiratory parameters during colonoscopy has not been studied in controlled, prospective trials.

METHODS

One hundred eighty patients undergoing colonoscopy were divided into 3 groups: (1) sedation with intravenous midazolam (midazolam group); (2) sedation with intravenous saline (placebo group); and (3) no intravenous cannula (control group). Arterial oxygen saturation (SaO(2)), systolic and diastolic blood pressure and continuous electrocardiogram were recorded prior to, during and after the endoscopic procedure.

RESULTS

Midazolam produced lower SaO(2) values during colonoscopy compared with placebo or control groups (p < 0.001, repeated measures analysis of variance). Systolic and diastolic blood pressure during colonoscopy were lower in the midazolam group than in the placebo group (p < 0.01 and p < 0.05, respectively), but no difference was found between the midazolam and the control groups. Hypotension (systolic blood pressure less than 100 mm Hg) occurred more frequently in the midazolam group (19%) than in the placebo (3%; p < 0.01) or control groups (7%; p < 0.05). ST-segment depression developed in 7% of patients during the recording with no difference between the groups. In 75% of cases ST-depression appeared prior to the endoscopic procedure.

CONCLUSIONS

Premedication with midazolam induced a statistically significant decrease in arterial oxygen saturation and increased the risk for hypotension. However, colonoscopy proved to be a safe procedure both with and without sedation.

A comparison of midazolam and diazepam for conscious sedation during colonoscopy in a prospective double-blind study

BACKGROUND

Midazolam and diazepam are commonly used for conscious sedation, but their comparative respiratory depressive effects have not been accurately studied. We used a novel real-time, on-line, computerized data acquisition system to compare the two agents in a randomized double-blind study.

METHODS

One hundred patients undergoing colonoscopy were studied. The maximum end-tidal carbon dioxide tension (PetCO2) and the minimum oxygen saturation by pulse oximetry (SpO 2) were recorded by computer every minute. Patients received meperidine (25 to 50 mg) and incremental doses of either midazolam or diazepam to an identical end point of slurred speech and/or ptosis. Sedation was scored from 1 (unarousable) to 5 (wide awake).

RESULTS

Sedation scores were 3.6 +/- 0.1 (mean +/- standard error) after each agent. The doses of midazolam and diazepam were 0. 031 +/- 0.002 and 0.106 +/- 0.009 mg/kg, respectively. In the first 45 minutes (PetCO2) was significantly higher with midazolam than with diazepam (p < 0.05). SpO2 was significantly depressed for 80 minutes after each agent, and the number of minutes when the minimum Sp O2 was less than 90% did not differ between the two agents.

CONCLUSIONS

Midazolam was 3.4 times more potent than diazepam. The duration of oxygen desaturation emphasizes the importance of monitoring SpO2 until ventilation and oxygenation have recovered. Although the degree of hypoxemia was comparable, midazolam led to higher end-tidal carbon dioxide tensions.

Sedation and analgesia for colonoscopy: patient tolerance, pain, and cardiorespiratory parameters

BACKGROUND

Colonoscopy is generally performed with the patient sedated and receiving analgesics. However, the benefit of the most often used combination of intravenous midazolam and pethidine on patient tolerance and pain and its cardiorespiratory risk have not been fully defined.

METHODS

In this double-blind prospective study, 150 outpatients undergoing routine colonoscopy were randomly assigned to receive either (1) low-dose midazolam (35 micrograms/kg) and pethidine (700 micrograms/kg in 48 patients, 500 micrograms/kg in 102 patients), (2) midazolam and placebo pethidine, or (3) pethidine and placebo midazolam.

RESULTS

Tolerance (visual analog scale, 0 to 100 points: 0 = excellent; 100 = unbearable) did not improve significantly more in group 1 compared with group 2 (7 points; 95% confidence interval [-2-17]) and group 3 (2 points; 95% confidence interval [-7-12]). Similarly, pain was not significantly improved in group 1 as compared with the other groups. Male gender (p < 0.001) and shorter duration of the procedure (p = 0.004), but not amnesia, were associated with better patient tolerance and less pain. Patient satisfaction was similar in all groups. Oxygen desaturation and hypotension occurred in 33% and 11%, respectively, with a similar frequency in all three groups.

CONCLUSIONS

In this study, the combination of low-dose midazolam and pethidine does not improve patient tolerance and lessen pain during colonoscopy as compared with either drug given alone. When applying low-dose midazolam, oxygen desaturation and hypotension do not occur more often after combined use of both drugs. For the individual patient, sedation and analgesia should be based on the endoscopist's clinical judgement.

No effect of oxygen therapy on myocardial ischaemia during gastroscopy

BACKGROUND

Myocardial ischaemia (defined as an ST-segment depression on ECG) may occur during upper gastrointestinal endoscopy, but the mechanism is still unknown. The aim of our study was to evaluate the effect of oxygen therapy and tachycardia on the occurrence of ST-segment depression during routine diagnostic esophagogastroduodenoscopy.

METHODS

Eighty-nine consecutive patients were randomized to receive either oxygen (21/min by nasal prongs) or nothing during endoscopy, in which arterial oxygen saturation was measured by continuous pulse oximetry, and ECG was measured continuously with a Holter tape recorder.

RESULTS

A total of 28 patients (12 receiving oxygen) developed ST-segment depression ( > 0.1 mV) during endoscopy. In 22 patients (12 receiving oxygen) ST depression was related to tachycardia, and in 5 of these (none receiving oxygen) simultaneous episodic hypoxaemia was present during the event. Thus, in every case of ST depression related to episodic hypoxaemia there was simultaneous tachycardia. In six patients developing ST depression during endoscopy we did not find preendoscopy levels, and 63 patients (29 receiving oxygen) developed tachycardia during the procedure (rate > 100 min-1_.

CONCLUSIONS

Oxygen therapy had no significant effect on the occurrence of ST-segment depression during upper gastrointestinal endoscopy. The results suggest that tachycardia is more important than hypoxaemia in the pathogenesis of ST depression during gastroscopy.

Efficacy, safety, and cost of intravenous sedation versus general anesthesia in children undergoing endoscopic procedures

We prospectively evaluated 226 patients under 18 years of age who underwent 296 procedures, and intravenous sedation and general anesthesia were compared in regard to efficacy, safety, and cost. Children 6 to 9 years of age required the highest doses of midazolam (0.14 +/- 0.04 mg/kg) and meperidine (2.5 +/- 0.8 mg/kg). A Relative Adequacy Scale, constructed to assess each patient's arousal and cooperation during intravenous sedation, revealed a 95% completion rate. Heart rate monitored before, during, and after the procedure was similar in both groups during the procedure, but a lower preprocedure heart rate was noted in older patients having intravenous sedation, suggesting less patient anxiety. Average charges, excluding endoscopist's and pathology fees, were $768.52 in the intravenous sedation group versus $1,965.42 in the general anesthesia group. Endoscopic procedures can be performed safely, effectively, and at a lower cost to the patient under intravenous sedation in a properly equipped and staffed pediatric endoscopy suite.

Carbon dioxide retention and oxygen desaturation during gastrointestinal endoscopy

BACKGROUND

Pulse oximetry measures arterial oxygen saturation (SpO2), not hypoventilation, which is directly reflected by increases in carbon dioxide tension.

METHODS

In the present study, transcutaneous carbon dioxide tension (PtcCO2) and SpO2 were measured during 101 endoscopic procedures selected for long duration or comorbid illnesses, and relationships between hypercapnia and hypoxemia were evaluated. Nasal oxygen was administered only for sustained desaturation (SpO2 < 90%).

RESULTS

Mean peak increase in PtcCO2 was significantly higher in patients requiring oxygen for sustained desaturation (16.3 mm Hg; range, 4-52) than in patients breathing room air who had transient or no desaturation (10.2 mm Hg [range, 3-19] and 5.1 mm Hg [range, 0-15]). If nasal oxygen corrected desaturation, even transient recurrence of desaturation indicated worsening CO2 retention, which preceded respiratory arrest in one patient. Independent predictors of hypercapnia were fentanyl and midazolam doses, oxygen requirement, and dementia.

CONCLUSIONS

Severe hypoventilation may occur during endoscopy, undetected by clinical observation or pulse oximetry, but only in sedated patients who require supplemental oxygen to maintain SpO2 above 90%. After oxygen supplementation corrects desaturation, recurrence of desaturation implies severe hypoventilation and warrants limitation of further sedation.

Oxygenating mouthguard alleviates hypoxia during gastroscopy

A randomized study was carried out to determine the effect of oxygen (3 liters/min) via a novel oxygenating mouthguard (Oxyguard) on arterial oxygenation in 242 intravenously sedated patients undergoing gastroscopy. In another group of 21 patients, a randomized crossover study of arterial oxygen saturation using either the standard mouthguard or the oxygenating mouthguard (3 liters/min) was conducted. Significant O2 desaturation (pulse oximeter reading less than 90%) occurred in 25% of patients on room air but only 3% of those on oxygen (p less than 0.001). Severe desaturation (reading less than 85%) occurred in 5% of patients on room air but was prevented by the oxygenating mouthguard. Minimum oxygen saturation levels were significantly higher in patients on oxygen (90.5 +/- 0.3%) than on air (86.5 +/- 0.5%; p less than 0.001). In the crossover group, O2 saturation was uniformly higher in the recordings of all patients using the oxygenating mouthguard. In conclusion, administration of oxygen via the oxygenating mouthguard alleviates hypoxemia during gastroscopy and prevents severe oxygen desaturation. However, hypoxemia may occur even during use of supplemental oxygen. Hence, monitoring of arterial oxygenation is recommended.

Asleep on the job: sedation and monitoring during endoscopy

Gastrointestinal endoscopic procedures are invasive and carry a significant morbidity and mortality, even for diagnostic procedures (mortality of 1 in 2000 for upper gastrointestinal endoscopy). The commonest causes of death are cardiopulmonary complications, which may in part be related to sedative techniques. The clinical end-points for sedation need to be reappraised and should aim to induce amnesia rather than hypnosis. Endoscopists need to be familiar with the pharmacokinetic and pharmacodynamic properties of the benzodiazepines used for sedation. This applies particularly to the protracted half-lives of some benzodiazepines and the major drug interaction with significant synergy that occurs if opioids are used in combination with benzodiazepines. Thus appropriate doses of these drugs should be administered. The use of supplemental oxygen and pulse oximetry, combined with continuous intravenous access during the procedure should be standard practice. Endoscopists should be aware of national guidelines for safe endoscopic practice.

Monitoring and safety in endoscopy

Over 50% of the complications and 60% of the deaths associated with upper GI endoscopy are cardiopulmonary in type. Oxygen desaturation and cardiac arrhythmias at the time of endoscopy are common. Ways of trying to prevent hypoxia occurring are discussed. The most effective of these is the use of supplemental oxygen. Pulse oximeters are being used increasingly frequently by endoscopists. The way in which oximeters work is described in some depth, as are some of the potential errors that may result from their use. The author believes that, as in anaesthetic practice, pulse oximeters will be used ever more frequently by endoscopists and finally become standard equipment in all endoscopy units. The case for using continuous ECG monitoring and blood pressure measurement is briefly discussed. The ASGE have recently published their recommendations on monitoring patients undergoing GI endoscopic procedures. The BSG's own working party on safety and monitoring is in the process of finalizing its recommendations, and the final part of the chapter discusses the views of this working party and gives some insight into what its final recommendations are likely to be.