Sedation for upper gastrointestinal endoscopy: a comparative study of midazolam and diazepam

Academy of Medicine, Singapore clinical guideline on the use of sedation by non-anaesthesiologists during gastrointestinal endoscopy in the hospital setting

INTRODUCTION

In Singapore, non-anaesthesiologists generally administer sedation during gastrointestinal endoscopy. The drugs used for sedation in hospital endoscopy centres now include propofol in addition to benzodiazepines and opiates. The requirements for peri-procedural monitoring and discharge protocols have also evolved. There is a need to develop an evidence-based clinical guideline on the safe and effective use of sedation by non-anaesthesiologists during gastrointestinal endoscopy in the hospital setting.

METHODS

The Academy of Medicine, Singapore appointed an expert workgroup comprising 18 gastroenterologists, general surgeons and anaesthesiologists to develop guidelines on the use of sedation during gastrointestinal endoscopy. The workgroup formulated clinical questions related to different aspects of endoscopic sedation, conducted a relevant literature search, adopted Grading of Recommendations, Assessment, Development and Evaluation (GRADE) methodology and developed recommendations by consensus using a modified Delphi process.

RESULTS

The workgroup made 16 recommendations encompassing 7 areas: (1) purpose of sedation, benefits and disadvantages of sedation during gastrointestinal endoscopy; (2) pre-procedural assessment, preparation and consent taking for sedation; (3) Efficacy and safety of drugs used in sedation; (4) the role of anaesthesiologist administered sedation during gastrointestinal endoscopy; (5) performance of sedation; (6) post-sedation care and discharge after sedation; and (7) training in sedation for gastrointestinal endoscopy for non-anaesthesiologists.

CONCLUSION

These recommendations serve to guide clinical practice during sedation for gastrointestinal endoscopy by non-anaesthesiologists in the hospital setting.

Guidelines for sedation in gastroenterological endoscopy (second edition)

Sedation in gastroenterological endoscopy has become an important medical option in routine clinical care. Here, the Japan Gastroenterological Endoscopy Society and the Japanese Society of Anesthesiologists together provide the revised "Guidelines for sedation in gastroenterological endoscopy" as a second edition to address on-site clinical questions and issues raised for safe examination and treatment using sedated endoscopy. Twenty clinical questions were determined and the strength of recommendation and evidence quality (strength) were expressed according to the "MINDS Manual for Guideline Development 2017." We were able to release up-to-date statements related to clinical questions and current issues relevant to sedation in gastroenterological endoscopy (henceforth, "endoscopy"). There are few reports from Japan in this field (e.g., meta-analyses), and many aspects have been based only on a specialist consensus. In the current scenario, benzodiazepine drugs primarily used for sedation during gastroenterological endoscopy are not approved by national health insurance in Japan, and investigations regarding expense-related disadvantages have not been conducted. Furthermore, including the perspective of beneficiaries (i.e., patients and citizens) during the creation of clinical guidelines should be considered. These guidelines are standardized based on up-to-date evidence quality (strength) and supports on-site clinical decision-making by patients and medical staff. Therefore, these guidelines need to be flexible with regard to the wishes, age, complications, and social conditions of the patient, as well as the conditions of the facility and discretion of the physician.

Effectiveness and safety of sedation in gastrointestinal endoscopy: An opinion review

Although endoscopy is a less invasive procedure than surgery, patients can experience pain without sedation. Patients expect reduced pain during endoscopies from effective and safe sedatives. Midazolam and propofol are used for endoscopic sedation in many countries and regions. Midazolam is a widely available benzodiazepine, and many clinical trials have shown it to be an effective sedative. However, patients who are sedated with midazolam require rest in the recovery room due to its relatively long half-life, and an antagonist such as flumazenil may need to be administered in cases of deep or prolonged sedation. Propofol is a short-acting sedative with a short half-life and a quick recovery time. Therefore, the use of propofol has been increasing. However, propofol has a narrow margin of safety and often induces adverse effects such as respiratory depression. Also, propofol has no specific antagonist, and should be administered by an anesthesiologist or an endoscopist familiar with anesthesia. Remimazolam, which is a novel ultra-short-acting benzodiazepine, has recently gained attention. Remimazolam has a short half-life and an antagonist. Both effective and safe sedation is desired in accordance with the increasing need for sedative endoscopies. Therefore, in this review each sedative is summarized.

An Asian consensus on standards of diagnostic upper endoscopy for neoplasia

BACKGROUND

This is a consensus developed by a group of expert endoscopists aiming to standardise the preparation, process and endoscopic procedural steps for diagnosis of early upper gastrointestinal (GI) cancers.

METHOD

The Delphi method was used to develop consensus statements through identification of clinical questions on diagnostic endoscopy. Three consensus meetings were conducted to consolidate the statements and voting. We conducted a systematic literature search on evidence for each statement. The statements were presented in the second consensus meeting and revised according to comments. The final voting was conducted at the third consensus meeting on the level of evidence and agreement.

RESULTS

Risk stratification should be conducted before endoscopy and high risk endoscopic findings should raise an index of suspicion. The presence of premalignant mucosal changes should be documented and use of sedation is recommended to enhance detection of superficial upper GI neoplasms. The use of antispasmodics and mucolytics enhanced visualisation of the upper GI tract, and systematic endoscopic mapping should be conducted to improve detection. Sufficient examination time and structured training on diagnosis improves detection. Image enhanced endoscopy in addition to white light imaging improves detection of superficial upper GI cancer. Magnifying endoscopy with narrow-band imaging is recommended for characterisation of upper GI superficial neoplasms. Endoscopic characterisation can avoid unnecessary biopsy.

CONCLUSION

This consensus provides guidance for the performance of endoscopic diagnosis and characterisation for early gastric and oesophageal neoplasia based on the evidence. This will enhance the quality of endoscopic diagnosis and improve detection of early upper GI cancers.

Sedation for routine gastrointestinal endoscopic procedures: a review on efficacy, safety, efficiency, cost and satisfaction

Most gastrointestinal endoscopic procedures are now performed with sedation. Moderate sedation using benzodiazepines and opioids continue to be widely used, but propofol sedation is becoming more popular because its unique pharmacokinetic properties make endoscopy almost painless, with a very predictable and rapid recovery process. There is controversy as to whether propofol should be administered only by anesthesia professionals (monitored anesthesia care) or whether properly trained non-anesthesia personnel can use propofol safely via the modalities of nurse-administered propofol sedation, computer-assisted propofol sedation or nurse-administered continuous propofol sedation. The deployment of non-anesthesia administered propofol sedation for low-risk procedures allows for optimal allocation of scarce anesthesia resources, which can be more appropriately used for more complex cases. This can address some of the current shortages in anesthesia provider supply, and can potentially reduce overall health care costs without sacrificing sedation quality. This review will discuss efficacy, safety, efficiency, cost and satisfaction issues with various modes of sedation for non-advanced, non-emergent endoscopic procedures, mainly esophagogastroduodenoscopy and colonoscopy.

Prospective, randomized, placebo-controlled trial evaluating the efficacy and safety of propofol sedation by anesthesiologists and gastroenterologist-led teams using computer-assisted personalized sedation during upper and lower gastrointestinal endoscopy

BACKGROUND AND AIM

No randomized controlled studies comparing propofol versus no sedation have been reported. Comparative data demonstrating the efficacy and safety of propofol sedation by anesthesiologists (ANES), and gastroenterologist-led teams (GLT) using computer-assisted personalized sedation (CAPS), during routine gastrointestinal (GI) endoscopy in Japan do not exist. We aimed to demonstrate the safety and efficacy of propofol sedation versus no sedation (PLCB) when propofol is given by ANES or GLT, during routine GI endoscopy.

METHODS

Two hundred and seventy two American Society of Anesthesiologists (ASA) class I or II adults were prospectively enrolled in this multicenter study and randomized into three groups (PLCB, ANES, GLT). Ability to maintain moderate sedation, defined as MOAA/S scores of 2-4 for ≥50% of all MOAA/S measurements from scope-in to scope-out, was the primary endpoint. Secondary endpoints included patient (PSSI) and clinician (CSSI) satisfaction.

RESULTS

Proportion of subjects maintained in moderate sedation by ANES (88.1%) and GLT (94.5%) was significantly higher than PLCB (21.6%; P < 0.001); there was no difference between the ANES and GLT groups (P = 0.116). Mean PSSI scores for subjects sedated by ANES (81.2 ± 12.5) and GLT (80.8 ± 14.1) were significantly higher than PLCB (65.3 ± 19.7; P < 0.001) and mean CSSI scores were also significantly higher in both active treatment groups (75.5 ± 10.2, 77.9 ± 10.3) than PLCB (60.8 ± 18.6; P < 0.001).

CONCLUSION

Moderate sedation can be achieved and maintained with propofol, improving both patient and physician satisfaction, when propofol is given by an anesthesiologist or a gastroenterologist-led team using CAPS.

Midazolam for sedation before procedures

BACKGROUND

Midazolam is used for sedation before diagnostic and therapeutic medical procedures. It is an imidazole benzodiazepine that has depressant effects on the central nervous system (CNS) with rapid onset of action and few adverse effects. The drug can be administered by several routes including oral, intravenous, intranasal and intramuscular.

OBJECTIVES

To determine the evidence on the effectiveness of midazolam for sedation when administered before a procedure (diagnostic or therapeutic).

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL to January 2016), MEDLINE in Ovid (1966 to January 2016) and Ovid EMBASE (1980 to January 2016). We imposed no language restrictions.

SELECTION CRITERIA

Randomized controlled trials in which midazolam, administered to participants of any age, by any route, at any dose or any time before any procedure (apart from dental procedures), was compared with placebo or other medications including sedatives and analgesics.

DATA COLLECTION AND ANALYSIS

Two authors extracted data and assessed risk of bias for each included study. We performed a separate analysis for each different drug comparison.

MAIN RESULTS

We included 30 trials (2319 participants) of midazolam for gastrointestinal endoscopy (16 trials), bronchoscopy (3), diagnostic imaging (5), cardioversion (1), minor plastic surgery (1), lumbar puncture (1), suturing (2) and Kirschner wire removal (1). Comparisons were: intravenous diazepam (14), placebo (5) etomidate (1) fentanyl (1), flunitrazepam (1) and propofol (1); oral chloral hydrate (4), diazepam (2), diazepam and clonidine (1); ketamine (1) and placebo (3); and intranasal placebo (2). There was a high risk of bias due to inadequate reporting about randomization (75% of trials). Effect estimates were imprecise due to small sample sizes. None of the trials reported on allergic or anaphylactoid reactions. Intravenous midazolam versus diazepam (14 trials; 1069 participants)There was no difference in anxiety (risk ratio (RR) 0.80, 95% confidence interval (CI) 0.39 to 1.62; 175 participants; 2 trials) or discomfort/pain (RR 0.60, 95% CI 0.24 to 1.49; 415 participants; 5 trials; I² = 67%). Midazolam produced greater anterograde amnesia (RR 0.45; 95% CI 0.30 to 0.66; 587 participants; 9 trials; low-quality evidence). Intravenous midazolam versus placebo (5 trials; 493 participants)One trial reported that fewer participants who received midazolam were anxious (3/47 versus 15/35; low-quality evidence). There was no difference in discomfort/pain identified in a further trial (3/85 in midazolam group; 4/82 in placebo group; P = 0.876; very low-quality evidence). Oral midazolam versus chloral hydrate (4 trials; 268 participants)Midazolam increased the risk of incomplete procedures (RR 4.01; 95% CI 1.92 to 8.40; moderate-quality evidence). Oral midazolam versus placebo (3 trials; 176 participants)Midazolam reduced pain (midazolam mean 2.56 (standard deviation (SD) 0.49); placebo mean 4.62 (SD 1.49); P < 0.005) and anxiety (midazolam mean 1.52 (SD 0.3); placebo mean 3.97 (SD 0.44); P < 0.0001) in one trial with 99 participants. Two other trials did not find a difference in numerical rating of anxiety (mean 1.7 (SD 2.4) for 20 participants randomized to midazolam; mean 2.6 (SD 2.9) for 22 participants randomized to placebo; P = 0.216; mean Spielberger's Trait Anxiety Inventory score 47.56 (SD 11.68) in the midazolam group; mean 52.78 (SD 9.61) in placebo group; P > 0.05). Intranasal midazolam versus placebo (2 trials; 149 participants)Midazolam induced sedation (midazolam mean 3.15 (SD 0.36); placebo mean 2.56 (SD 0.64); P < 0.001) and reduced the numerical rating of anxiety in one trial with 54 participants (midazolam mean 17.3 (SD 18.58); placebo mean 49.3 (SD 29.46); P < 0.001). There was no difference in meta-analysis of results from both trials for risk of incomplete procedures (RR 0.14, 95% CI 0.02 to 1.12; downgraded to low-quality evidence).

AUTHORS' CONCLUSIONS

We found no high-quality evidence to determine if midazolam, when administered as the sole sedative agent prior to a procedure, produces more or less effective sedation than placebo or other medications. There is low-quality evidence that intravenous midazolam reduced anxiety when compared with placebo. There is inconsistent evidence that oral midazolam decreased anxiety during procedures compared with placebo. Intranasal midazolam did not reduce the risk of incomplete procedures, although anxiolysis and sedation were observed. There is moderate-quality evidence suggesting that oral midazolam produces less effective sedation than chloral hydrate for completion of procedures for children undergoing non-invasive diagnostic procedures.

Basic principles and practice of gastric cancer screening using high-definition white-light gastroscopy: Eyes can only see what the brain knows

Endoscopic diagnosis of gastrointestinal tumors consists of the following processes: (i) detection; (ii) differential diagnosis; and (iii) quantitative diagnosis (size and depth) of a lesion. Although detection is the first step to make a diagnosis of the tumor, the lesion can be overlooked if an endoscopist has no knowledge of what an early-stage 'superficial lesion' looks like. In recent years, image-enhanced endoscopy has become common, but white-light endoscopy (WLI) is still the first step for detection and characterization of lesions in general clinical practice. Settings and practice of routine esophagogastroduodenoscopy (EGD) such as use of antispasmodics, number of endoscopic images taken, and observational procedure are customarily decided in each facility in each country and are not well standardized. Therefore, in the present article, we attempted to outline currently available evidence and actual Japanese practice on gastric cancer screening using WLI, and provide tips for detecting EGC during routine EGD which could become the basis of future research.

Prospective long-term assessment of sedation-related adverse events and patient satisfaction for upper endoscopy and colonoscopy

BACKGROUND

Fear of pain and sedation-related adverse events are impediments for patients to attend endoscopic screening or surveillance programs.

OBJECTIVE

To investigate the long-term effect of different sedation protocols in patients undergoing screening or surveillance endoscopy. Moreover, motivation of patients to decline endoscopic procedures was evaluated by focusing on the patient's satisfaction, fear and pain in relation to type of sedation used.

DESIGN

A prospective, double-blind controlled trial data collection was performed by using a standardized clinical questionnaire followed by a telephone interview 3-4 weeks after the initial endoscopic procedure.

SETTING

The study was conducted at the Department of Medicine I at the University Hospital of Erlangen-Nuremberg. Data collection was performed during June 2012 till April 2013.

PATIENTS

Overall, 307 patients were prospectively evaluated (44.3% female, mean age 51 ± 17.4 years; mean BMI 25.5 ± 5.7). 247 patients (80.5%) were outpatients, 60 inpatients (19.5%).

INTERVENTIONS

Endoscopic procedures were divided into five groups: (i) procedures in the upper gastrointestinal tract, (ii) complete colonoscopies, (iii) ileocolonoscopies, (iv) incomplete colonoscopies, and (v) other procedures.

MAIN OUTCOME MEASUREMENTS

Patient satisfaction, fear and pain were measured in a structured and standardized clinical interview using a 6-point numerical rating scale, where 1 was 'very satisfied/no pain' and 6 was 'very unsatisfied/unsupportable pain'.

RESULTS

Different types of sedation were assessed: propofol in monosedation (6.5%), combination of propofol + meperidine (41.0%), combination of midazolam + meperidine (48.5%) and other combinations (3.9%). Patient satisfaction was significantly reduced regarding fear and pain during the endoscopic procedure (p = 0.001 and p = 0.0001, respectively). All patients receiving propofol monosedation indicated significantly less pain in comparison to other sedation groups (p < 0.0001). Moreover, sedation with midazolam + meperidine increased the fear during the procedure significantly in comparison to monosedation with propofol (p = 0.082). Propofol/meperidine in combination and midazolam/meperidine increased the probability for cardiovascular events in comparison to monosedation with propofol (p = 0.005; p = 0.039). Finally, we observed significantly lower doses of propofol when used in monosedation than propofol in combination with meperidine (p = 0.066).

LIMITATION

Single-center study at a tertiary referral center.

CONCLUSIONS

Propofol in monosedation should preferably be used for patient sedation in screening and surveillance endoscopies. Whether this approach could also improve participation rates in screening and surveillance endoscopies requires further investigations.

Guidelines for sedation in gastroenterological endoscopy

Recently, the need for sedation in gastrointestinal endoscopy has been increasing. However, the National Health Insurance Drug Price list in Japan does not include any drug specifically used for the sedation. Although benzodiazepines are the main medication, their use in cases of gastrointestinal endoscopy has not been approved. This has led the Japan Gastrointestinal Endoscopy Society to develop the first set of guidelines for sedation in gastrointestinal endoscopy on the basis of evidence-based medicine in collaboration with the Japanese Society for Anesthesiologists. The present guidelines comprise 14 statements, five of which were judged to be valid on the highest evidence level and three on the second highest level. The guidelines are not intended to strongly recommend the use of sedation for gastrointestinal endoscopy, but rather to indicate the policy as to the choice of appropriate procedures when such sedation is deemed necessary. In clinical practice, the final decision as to the use of sedation should be made by physicians considering patient willingness and physical condition.

Recommended sedation and intraprocedural monitoring for gastric endoscopic submucosal dissection

Endoscopic submucosal dissection is associated with a longer treatment time and a higher risk of patient discomfort than conventional procedures. Adequate, safe sedation is therefore essential. Sedation can cause adverse effects such as hypoxemia and hypotension, requiring continuous intraoperative and postoperative monitoring of blood pressure, use of the electrocardiogram, and arterial blood oxygen saturation by pulse oximetry. A physician and a nurse solely responsible for sedating and monitoring the patient should be present during treatment.A combination of benzodiazepines and analgesics are generally used for sedation, but new sedatives such as propofol and dexmedetomidine hydrochloride are expected to be useful agents. Endoscopists should become more familiar with sedatives, analgesics, and emergency procedures in the future.

Sedation, analgesia, and monitoring

Endoscopic procedures are common and sedation is frequently used to minimize anxiety and discomfort, reduce the potential for physical injury during the procedure, and improve overall patient tolerability and satisfaction. In this article, the authors review the variety of options for sedation and analgesia available to the gastroenterologist or surgical endoscopist.

A systematic review and meta-analysis of randomized, controlled trials of moderate sedation for routine endoscopic procedures

BACKGROUND

Numerous agents are available for moderate sedation in endoscopy.

OBJECTIVE

Our purpose was to compare efficacy, safety, and efficiency of agents used for moderate sedation in EGD or colonoscopy.

DESIGN

Systematic review of computerized bibliographic databases for randomized trials of moderate sedation that compared 2 active regimens or 1 active regimen with placebo or no sedation.

PATIENTS

Unselected adults undergoing EGD or colonoscopy with a goal of moderate sedation.

MAIN OUTCOME MEASUREMENTS

Sedation-related complications, patient assessments (satisfaction, pain, memory, willingness to repeat examination), physician assessments (satisfaction, level of sedation, patient cooperation, examination quality), and procedure-related efficiency outcomes (sedation, procedure, or recovery time).

RESULTS

Thirty-six studies (N = 3918 patients) were included. Sedation improved patient satisfaction (relative risk [RR] = 2.29, range 1.16-4.53) and willingness to repeat EGD (RR = 1.25, range 1.13-1.38) versus no sedation. Midazolam provided superior patient satisfaction to diazepam (RR = 1.18, range 1.07-1.29) and less frequent memory of EGD (RR = 0.57, range 0.50-0.60) versus diazepam. Adverse events and patient/physician assessments were not significantly different for midazolam (with or without narcotics) versus propofol except for slightly less patient satisfaction (RR = 0.90, range 0.83-0.97) and more frequent memory (RR = 3.00, range 1.25-7.21) with midazolam plus narcotics. Procedure times were similar, but sedation and recovery times were shorter with propofol than midazolam-based regimens.

LIMITATIONS

Marked variability in design, regimens tested, and outcomes assessed; relatively poor methodologic quality (Jadad score </=3 in 23/36 trials).

CONCLUSIONS

Moderate sedation provides a high level of physician and patient satisfaction and a low risk of serious adverse events with all currently available agents. Midazolam-based regimens have longer sedation and recovery times than does propofol.

A controlled study of the effect of midazolam on abnormal sphincter of Oddi motility

BACKGROUND

The effect of a medication on sphincter of Oddi motility should be characterized if it is to be used during sphincter of Oddi manometry. Controversy exists as to whether midazolam influences sphincter of Oddi motility. This study assessed the effect of midazolam on the hypertensive sphincter of Oddi.

METHODS

The study population consisted of 36 patients who presented with recurrent abdominal pain resulting from sphincter of Oddi dysfunction. The study was nonrandomized, prospective, and placebo controlled. Patient allocation was consecutive. Sphincter of Oddi manometry was performed in standard fashion. Manometric tracings were interpreted while the investigator was blinded to treatment allocation. Eighteen patients in the test group received 2 mg of midazolam intravenously whereas the 18 patients in the control group received saline solution intravenously. Manometric parameters were measured before and 3 minutes after the intravenous infusion. Changes in manometric findings before and after the administration of saline solution and midazolam were compared.

RESULTS

Midazolam caused a significant reduction in basal sphincter of Oddi pressure (24 mm Hg) as compared with saline solution (p < 0.001). Diagnostic concordance (normal vs. abnormal) between the basal sphincter pressure before and after midazolam was seen in only 77% of patients.

CONCLUSIONS

Midazolam significantly altered sphincter of Oddi motility. The decrease in sphincteric pressures would have altered diagnosis and management in 4 of 18 patients. Midazolam should not be used during sphincter of Oddi manometry.

Children's knowledge, anticipatory anxiety, procedural distress, and recall of esophagogastroduodenoscopy

BACKGROUND

This study evaluates the relations among children's knowledge of esophagogastroduodenoscopy (EGD) and anticipatory anxiety, procedural distress, and the nature of postprocedural recall and evaluations.

METHODS

One hundred patients, aged 8 to 17 years, completed self-report measures of knowledge and anxiety before EGD. Parents completed a self-report measure assessing how they prepared their children. Nurses and trained observers completed observational ratings of distress. Children's recall and evaluation of the procedure were assessed by self-report 1 hour after the procedure and by telephone that evening.

RESULTS

Most children knew about the major components of EGD. Children with greater knowledge experienced less distress and reported that they would be less anxious and upset when undergoing future EGDs. Children with greater anticipatory anxiety exhibited more procedural distress. Children's distress varied by the phase of the procedure. Children who were more distressed during intravenous line insertion experienced greater distress during esophageal intubation and the endoscopic examination. Approximately 20% of patients reported at least some memory of the procedure even at the end of the day. Children with greater recall reported greater aversion and a more negative attitude toward future EGDs.

CONCLUSIONS

This study provides information about children's distress during EGD and the effects of conscious sedation on patients' memories and attitudes toward future procedures. The study indicates that preparation before EGD may reduce patient distress.

Sedation for upper gastrointestinal endoscopy: a comparison of alfentanil-midazolam and meperidine-diazepam

The authors studied the efficacy and cost of substituting sedation using midazolam and alfentanil for the existing regimen of diazepam and meperidine in patients requiring upper gastrointestinal endoscopy. Sixty consenting subjects were randomized to receive either meperidine 50 mg with diazepam approximately 90 micrograms.kg-1 (Group D) or alfentanil 250 micrograms with midazolam approximately 50 micrograms.kg-1 (Group M). Endoscope insertion time, patient acceptance, apnoeic or desaturation episodes were noted by a physician observer. Pulse oximetry was used to monitor heart rate and oxygen saturation (SpO2) during endoscopy. Subjects performed four-choice reaction time (4CRT) tests before, 30 and 60 min after endoscopy, and were assessed for nausea or dizziness and their ability to stand and walk. During endoscopy, insertion time was shorter (84 +/- 45 sec vs 122 +/- 83 sec, P < 0.03) and fewer aversive movements occurred (0.4 +/- 0.6 vs. 1.7 +/- 2.4, P < 0.005) in Group M than Group D. No subject in either group suffered any apnoea or prolonged desaturation requiring supplemental oxygen. Irrespective of treatment group, greater decreases in SpO2 (6.1 +/- 3.4% vs 3.6 +/- 2.2% P < 0.001) occurred in subjects > 45 yr of age than in subjects < or = 45 yr. During recovery 4CRT values at 30 min after endoscopy were longer (723 +/- 226 msec vs 594 +/- 139 msec, P < 0.005) in Group M than in Group D but not after 60 min. It was concluded that the small differences in endoscopy conditions and greater sedation during the first 30 min of recovery did not justify the additional cost of using midazolam and alfentnil.(ABSTRACT TRUNCATED AT 250 WORDS)

Venous complications of midazolam versus diazepam

Although some studies have suggested fewer venous complications are associated with midazolam than with diazepam for endoscopic procedures, this variable has not been well documented. We prospectively evaluated the incidence of venous complications after intravenous injection of diazepam or midazolam in 122 consecutive patients undergoing colonoscopy and esophagogastroduodenoscopy. Overall, venous complications were more frequent with diazepam (22 of 62 patients) than with midazolam (4 of 60 patients) (p < 0.001). A palpable venous cord was present in 23% (14 of 62) of patients in the diazepam group, compared with 2% (1 of 60 patients) in the midazolam group (p < 0.002). Pain at the injection site occurred in 35% (22 of 62) of patients in the diazepam group compared with 7% (4 of 60 patients) in the midazolam group (p < 0.001). Swelling and warmth at the injection site were not significantly different between the two groups. Smoking, nonsteroidal anti-inflammatory drug use, intravenous catheter site, dwell time of the needle, alcohol use, and pain during the injection had no effect on the incidence of venous complications.

Age, anemia, and obesity-associated oxygen desaturation during upper gastrointestinal endoscopy

Although upper gastrointestinal endoscopy is generally a safe procedure, it is known to be associated with arterial oxygen desaturation. We studied 82 patients undergoing diagnostic upper gastrointestinal endoscopy following a standard premedication consisting of xylocaine throat spray and intravenous midazolam. The mean duration of endoscopy was 8.5 +/- 0.42 min and the mean dose of midazolam was 6.3 +/- 0.15 mg. The baseline SaO2 was 94.91 +/- 0.27% and it decreased after pre-medication to 92.84 +/- 0.40% (p < 0.001) and after intubation to 91.21 +/- 0.40% (p < 0.001). A fall greater than 4% saturation occurred for 15.68% of the total endoscopy time. SaO2 < 90% was seen for 16.7% and SaO2 < 85% occurred for 2.33% total endoscopy time. In patients > 65 years old, hemoglobin < 10 g/dl, or body mass index > 28, the baseline saturation was significantly lower and a reduced SaO2 was seen throughout the procedure. We identify old age, anemia, and obesity as independent risk factors for arterial oxygen desaturation. We recommend continuous monitoring before sedation, and giving supplemental oxygen to patients with these risk factors from the outset of upper gastrointestinal endoscopy.

Diazepam versus midazolam for colonoscopy: a prospective evaluation of predicted versus actual dosing requirements

We performed a prospective, randomized, double-blind study to evaluate the efficacy of the currently recommended low doses of midazolam for conscious sedation compared with diazepam for colonoscopy. Each agent was administered in a fixed ratio dose in combination with meperidine, and titrated incrementally to allow for adequate sedation prior to initiating and during the procedure. The currently recommended starting dose of midazolam (0.03 mg/kg) proved to be very appropriate for pre-medication. In contrast, the currently recommended starting dose of diazepam (0.10 mg/kg) proved excessive in 21% of patients (especially in those aged > 65). The low initial and incremental doses of midazolam compared favorably with diazepam in all efficacy parameters studied and exceeded diazepam in post-procedure amnesia scores (p = 0.01). Moreover, the sedative effects of midazolam at these lower doses were not lost despite long duration procedures (> 40 min). We conclude that midazolam, given in small incremental doses, in combination with meperidine, produces effective conscious sedation for colonoscopy and exceeds diazepam in its amnestic effect.

Evaluation of safe, effective intravenous sedation for utilization in endoscopic procedures

The prevention of anesthetic mishaps during endoscopic procedures is of great importance to physicians in training. With the large number of such procedures performed each year, even infrequent adverse anesthetic reactions may result in a significant number of problems. To establish the safety and efficacy of an anesthetic regimen using intravenous meperidine and diazepam, all endoscopic procedures performed at one teaching institution in a 4-month period were retrospectively analyzed with regard to: (1) type and dosage of sedation/anesthesia, (2) endoscopic procedure involved, (3) effect of any underlying disease state, (4) side effects, (5) endoscopic complications, and (6) overall patient acceptance. A total of 716 patients underwent 913 endoscopic procedures with 876 separate anesthetic/intravenous sedations. General anesthesia was utilized in 44% of the 155 pediatric procedures. In the adult patients, intravenous sedation was administered by a physician-in-training under supervision except in 9% of cases (66 patients) when intravenous sedation utilizing alternative agents was given by the anesthesia department. The dose of sedation used (per body weight) declined with increasing age in the pediatric group (0-19 years). The adult dose remained constant for the next eight decades of life (meperidine 0.76 +/- 0.33 mg/kg: diazepam 0.12 +/- 0.08 mg/kg). In the adult group, 758 procedures were performed: 371 patients underwent esophago-gastroduodenoscopy, 258 colonoscopy, 36 endoscopic retrograde cholangiopancreatography, 40 flexible sigmoidoscopy, and 51 percutaneous endoscopic gastrostomy. Anesthetic-related complications (transient apnea and itching), were noted in two patients, and naloxone was utilized to reverse oversedation in a further 17 (2.56%).(ABSTRACT TRUNCATED AT 250 WORDS)

Review article: premedication and intravenous sedation for upper gastrointestinal endoscopy

Upper gastrointestinal endoscopy can be performed without intravenous sedation but the evidence suggests that, in the United Kingdom and United States, most patients and endoscopists prefer that some form of premedication is given. Intravenous diazepam or midazolam are used by the majority of endoscopists. In the UK, the ratio of diazepam to midazolam users is approximately 2:1, while in the USA more endoscopists are now using midazolam. Midazolam is approximately twice as potent as diazepam but, when allowance is made for this, there is probably little or no difference in the propensity of the two drugs to produce respiratory depression. The antegrade amnesic effect of midazolam is significantly superior to that of diazepam. A benzodiazepine/narcotic combination can achieve a smoother and more rapid induction with less gagging and choking, but the incidence of adverse outcomes--particularly respiratory depression--is increased significantly. Over 50% of the deaths that are associated with upper gastrointestinal endoscopy are due to cardiopulmonary problems. Hypoxia is very common if measured using non-invasive monitoring equipment, such as a pulse oximeter. Methods of preventing oxygen desaturation and thus, by inference, most cardiac arrhythmias associated with endoscopy are discussed, as is the role of flumazenil, the new benzodiazepine antagonist.