Monitoring and safety in endoscopy

Effects of high-resolution esophageal manometry on oxygen saturation and hemodynamic function

The effect of high-resolution esophageal manometry (HRM) on oxygen saturation (SaO2) and hemodynamic function has not been previously evaluated. This was a prospective study of consecutive patients referred for HRM. Demographic and clinical data were collected on all patients. The study variables included SaO2, heart rate (HR) and blood pressure (BP). SaO2 and HR were measured at baseline, during intubation, during and 5 min after HRM. BP was measured at baseline, during and after HRM. 158 (56% women) patients with a mean age of 56 (SD 15) years were included. Thirty-five (22%) were obese and 55 (35%) were overweight. Eighteen (12%) patients had a history of respiratory disease and 27 (17%) were smokers. Intubation was difficult in 22%. Exploration tolerance was poor in 17% or very poor in 6%. The average duration of the test was 9.9 (SD 2.8) minutes. Sixty-four (47%) and 59 (37%) patients had SaO2 below 95% during intubation and during HRM, respectively. Three patients had SaO2 ≤90%. Sixty-nine (44%) patients had tachycardia during intubation and 8 (5%) during HRM. The appearance of desaturation (SaO2 <95%) during intubation was associated with a lower basal SaO2; desaturation during HRM and 5 minutes after HRM was associated with a higher age, a higher BMI and a lower basal SaO2. HRM decreases SaO2 and increases heart rate primarily during the insertion of the probe, as part of the standard stress response and therefore HMR can be considered a safe procedure. However, in older and overweight patients, respiratory parameters should be monitored.

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.

A national study of cardiopulmonary unplanned events after GI endoscopy

BACKGROUND

Cardiopulmonary unplanned events (CUE) related to conscious sedation constitute a major proportion of GI endoscopy-associated complications.

OBJECTIVES

Our purpose was to study the incidence of CUE during GI endoscopy and to determine factors that may predict CUE.

DESIGN

Retrospective CORI (Clinical Outcomes Research Initiative) database review.

PATIENTS

Undergoing GI endoscopy under conscious sedation.

MAIN OUTCOME MEASUREMENT

CUE associated with GI endoscopy.

RESULTS

Data on 324,737 unique procedures (EGD, 140,692; colonoscopy, 174,255; ERCP, 6092; and EUS, 3698) performed with the patient under conscious sedation were analyzed. Unplanned events were reported in 1.4% of procedures; 0.9% were associated with CUE. Rates of CUE with EGD, colonoscopy, ERCP, and EUS were 0.6%, 1.1%, 2.1%, and 0.9%, respectively. Multiple logistic regression revealed patient age (odds ratio [OR] 1.02, 95% CI 1.01-1.02) and ASA class were significant predictors of CUE (OR compared with ASA I: ASA II 1.05, 95% CI 0.95-1.16; ASA III 1.8, 95% CI 1.6-2.0, ASA IV 3.2, 95% CI 2.5-4.1, ASA V 7.5; 95% CI 3.2-17.6). Inpatient procedures were associated with higher CUE (OR 1.5, 95% CI 1.3-1.7). Compared with universities, nonuniversity sites (OR 1.2, 95% CI 1.1-1.4) and Veterans Administration Medical Centers (OR 1.4, 95% CI 1.2-1.5) had significantly higher CUE. Use of supplemental oxygen during a procedure was associated with significantly more CUE (OR 1.2, 95% CI 1.1-1.3). Involvement of a trainee with a procedure was also associated with higher CUE (OR 1.3, 95% CI 1.1-1.4).

LIMITATIONS

Retrospective review of data entered voluntarily by endoscopists not trained on CORI data entry.

CONCLUSIONS

During GI endoscopy with conscious sedation, patient's age, higher ASA grade, inpatient status, trainee participation, and routine use of oxygen are associated with a higher incidence of CUE.

Extended/advanced monitoring techniques in gastrointestinal endoscopy

The practice of sedation and analgesia is under increasing scrutiny by numerous regulatory agencies, with the aim of making these procedures safer and reducing the incidence of cardiopulmonary complications during GI endoscopy. As we move toward more evidence-based medicine, new technologies will have to be assessed in a manner that demonstrates their efficacy and utility in clinical practice. Although there have been no controlled studies examining whether more intensive monitoring during endoscopy improves outcomes, extended monitoring with capnography seems to offer an advantage over conventional monitoring in that, by providing a real-time indication of any change in adequate ventilation before oxygen desaturation occurs, it can detect early phases of respiratory depression, which can allow a more precise and safer titration of medications. There is a close agreement among experts that capnography may reduce the risk of adverse outcomes during deep sedation; therefore, its use should be required for patients undergoing advanced endoscopic procedures with the potential for deep sedation. Extended monitoring with capnography should also be endorsed whenever propofol is considered as an alternative to standard sedation with a benzodiazepine or narcotic. Our understanding of the clinical application of techniques for monitoring of depth of sedation is in its infancy, and its full contribution to the practice of endoscopy has yet to be determined. Their potential role in improving sedation practice during endoscopy needs to be confirmed by controlled trials. If we consider the lack of proven efficacy of these emerging monitoring techniques in reducing the adverse outcomes associated with sedation and analgesia, the importance of appropriate monitoring cannot be overemphasized. However, it is vital for the endoscopist to be thoroughly familiar with the type of sedation chosen, to be able to recognize the various levels of sedation, and, above all, to rescue patients should they unintentionally progress to a deeper level of sedation than intended.

Oxygen desaturation during oesophageal manometry

Eighteen generally fit clinical patients were monitored with pulse oximetry. Mean oxygen saturation levels were lower (P<0.05) during oesophageal manometry (97.7-97.3%) than before it (98.3%). Fourteen out of seventeen (successful) traces had short 4-8% desaturation episodes, and in worst cases there were 8-9 episodes. It seems, therefore, that even patients with no predisposing factors than perhaps smoking and mild bronchial asthma are vulnerable to some oxygen desaturation in oesophageal manometry.

Patient-controlled analgesia for conscious sedation during colonoscopy: a randomized controlled study

BACKGROUND

The aim of this study was to assess whether patient-controlled anesthesia (PCA) can improve patient tolerance for colonoscopy. We compared baseline sedation and analgesia with baseline sedation and PCA.

METHODS

Fifty-six consecutive patients were alternatively allocated to 1 of 2 groups: either to control group (n = 28) to receive standard sedation (meperidine and midazolam as baseline and additional doses of meperidine administered by the anesthesiologist) or to a PCA group (n = 28) to receive the same baseline premedication but additional analgesia with meperidine being self-administered. Cardiopulmonary parameters were recorded and tolerance for the examination was evaluated by a numeric rating scale, 0 meaning "no pain" and 10 meaning "maximal pain."

RESULTS

Patients' mean pain score (on a scale of 0 to 10) was 4.85 +/- 3.74 for the PCA group and 5.30 +/- 3.53 (not significant) for the control group. Physicians' assessment of patient tolerance registered a lower numeric rating score than patients' assessment. The duration of the procedure was slightly longer in the PCA group. None of the patients experienced a decline in oxygen saturation below 90%; a decrease in expiratory carbon dioxide during the examination was noted in both groups of patients, particularly during the first minutes of the examination. Mean additional sedation per patient in the PCA group was slightly higher, but not significantly different.

CONCLUSIONS

Our results suggest that patient-controlled analgesia during colonoscopy is as effective as standard sedation with respect to patient tolerance and safety of the examination.

A randomized, controlled trial of transcutaneous carbon dioxide monitoring during ERCP

BACKGROUND

Pulse oximetry, used to monitor oxygen saturation during endoscopy, does not directly measure hypoventilation. Study goals were to determine whether transcutaneous carbon dioxide (PtcCO(2)) monitoring during endoscopic retrograde cholangiopancreatography (ERCP) prevents severe hypoventilation and to assess the accuracy of clinical observation and pulse oximetry in detecting hypoventilation.

METHODS

All patients received intensive clinical and electronic monitoring including pulse oximetry. Supplemental oxygen was administered for pulse oximetry < 90%. Patients were randomized to a treatment arm (group 1) where PtcCO(2) monitoring guided sedation or a control arm (group 2) where PtcCO(2) was recorded but unavailable for guiding sedation.

RESULTS

Group 1 had significantly fewer episodes of severe carbon dioxide retention (rise in PtcCO(2) >/=40 mm Hg above baseline) than group 2 (0 of 199 versus 5 of 196, respectively, p = 0.03), as well a shorter mean duration of procedure discomfort (8.3% of procedure duration rated as "uncomfortable" versus 11.5%, p = 0.04). Correlations between clinical observation and objective measures of ventilation were poor: level of sedation versus PtcCO(2) (R = 0.3) or pulse oximetry (R = 0.06); slowest respiratory rate versus PtcCO(2) (R = 0.4) or pulse oximetry (R = -0.4). PtcCO(2) rises of greater than 20 mm Hg occurred without oxygen desaturation in 10.7% of patients receiving supplemental oxygen.

CONCLUSIONS

Carbon dioxide retention during ERCP is not reliably detected by clinical observation or by pulse oximetry in patients receiving supplemental oxygen. The addition of PtcCO(2) monitoring prevents severe carbon dioxide retention more effectively than intensive clinical monitoring and pulse oximetry alone. The clinical relevancy of this observation needs to be determined in an appropriately designed outcome study.

A comparison of transnasal and transoral oesophagogastroduodenoscopy

Transnasal oesophagogastroduodenoscopy (OGD) with a narrow-bore endoscope has been demonstrated to be feasible in unsedated volunteers. The aim of the study was to compare efficacy, safety, patient tolerance and costs between this novel approach to OGD and standard sedated OGD. Sixty day patients were enrolled for either sedated transoral endoscopy with a standard calibre endoscope or for unsedated transnasal endoscopy with a narrow-bore (5.3 mm diameter) endoscope. Visualization was unsatisfactory in one examination in each group. The only complications were minor epistaxis in four of the transnasal group and oxygen desaturation below 90% in two of the sedated transoral group. On a 1 (very uncomfortable) to 5 (very comfortable) visual analogue scale, the mean transnasal group score was 3.09, compared with 3.86 in the transoral group (P = 0.013). In the transnasal group, mean procedure room time was 15 min compared with 20 min in the transoral group (P < 0.0003), and mean recovery room time was 7 min compared with 37 min (P < 0.0001). Consumable and pharmaceutical costs were reduced by 65 and 92%, respectively. This study demonstrates that unsedated transnasal OGD is a safe and effective route for OGD and has acceptable patient tolerance. The safety and decreased recovery times offer major cost savings and the potential for this method of OGD to become an office procedure for the investigation of the upper gastrointestinal tract.

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.

Conscious sedation for gastroscopy: patient tolerance and cardiorespiratory parameters

BACKGROUND/AIMS

Most patients receive conscious sedation for gastroscopy. However, the benefit of the most often used combination of low-dose intravenous midazolam and topical lidocaine on patient tolerance remains poorly defined and has not been shown to outweigh cardiorespiratory risks. To respond to these issues, a randomized, double-blind, placebo-controlled prospective study was performed.

METHODS

Two hundred outpatients undergoing diagnostic gastroscopy were assigned to receive either (1) midazolam (35 micrograms/kg) and lidocaine spray (100 mg), (2) midazolam and placebo lidocaine, (3) placebo midazolam and lidocaine, or (4) placebo midazolam and placebo lidocaine.

RESULTS

Tolerance (visual analogue scale, 0-100 points; 0, excellent; 100, unbearable) improved as compared with placebo midazolam and placebo lidocaine by 23 points (95% confidence interval, 15-32) in group 1, 15 points (95% confidence interval, 7-24) in group 2, and 10 points (95% confidence interval, 2-18) in group 3. Increasing age (P < 0.001), low anxiety (P < 0.001), and male sex (P < 0.03), but not amnesia, were associated with better patient tolerance. Oxygen desaturation (< 1 minute) occurred in 8.2% and was not more frequent after midazolam treatment. Hypotension was rare (2.1%), and no adverse outcome occurred.

CONCLUSIONS

Both low-dose midazolam (35 micrograms/kg) and lidocaine spray have an additive beneficial effect on patients tolerance and rarely induce significant alterations in cardiorespiratory monitoring parameters, thus supporting the widespread use of conscious sedation.