Cardiorespiratory changes during upper gastrointestinal endoscopy

Safety of gastrointestinal endoscopy with conscious sedation in obstructive sleep apnea

AIM

To perform a systematic review and meta-analysis to assess the safety of conscious sedation in patients with obstructive sleep apnea (OSA).

METHODS

A comprehensive electronic search of MEDLINE and EMBASE was performed from inception until March 1, 2015. In an effort to include unpublished data, abstracts from prior gastroenterological society meetings as well as other reference sources were interrogated. After study selection, two authors utilizing a standardized data extraction form collected the data independently. Any disagreements between authors were resolved by consensus among four authors. The methodological quality was assessed using the Newcastle Ottawa tool for observational studies. The primary variables of interest included incidence of hypoxia, hypotension, tachycardia, and bradycardia. Continuous data were summarized as odds ratio (OR) and 95%CI and pooled using generic inverse variance under the random-effects model. Heterogeneity between pooled studies was assessed using the I² statistic.

RESULTS

Initial search of MEDLINE and EMBASE identified 357 citations. A search of meeting abstracts did not yield any relevant citations. After systematic review and exclusion consensus meetings, seven studies met the a priori determined inclusion criteria. The overall methodological quality of included studies ranged from moderate to low. No significant differences between OSA patients and controls were identified among any of the study variables: Incidence of hypoxia (7 studies, 3005 patients; OR = 1.11; 95%CI: 0.73-1.11; P = 0.47; I² = 0%), incidence of hypotension (4 studies, 2125 patients; OR = 1.10; 95%CI: 0.75-1.60; P = 0.63; I² = 0%), incidence of tachycardia (3 studies, 2030 patients; OR = 0.94; 95%CI: 0.53-1.65; P = 0.28; I² = 21%), and incidence of bradycardia (3 studies, 2030 patients; OR = 0.88; 95%CI: 0.63-1.22; P = 0.59; I² = 0%).

CONCLUSION

OSA is not a significant risk factor for cardiopulmonary complications in patients undergoing endoscopic procedures with conscious sedation.

Continuous non-invasive arterial pressure technique improves patient monitoring during interventional endoscopy

INTRODUCTION

Close monitoring of arterial blood pressure (BP) is a central part of cardiovascular surveillance of patients at risk for hypotension. Therefore, patients undergoing diagnostic and therapeutic procedures with the use of sedating agents are monitored by discontinuous non-invasive BP measurement (NIBP). Continuous non-invasive BP monitoring based on vascular unloading technique (CNAP, CN Systems, Graz) may improve patient safety in those settings. We investigated if this new technique improved monitoring of patients undergoing interventional endoscopy.

METHODS

40 patients undergoing interventional endoscopy between April and December 2007 were prospectively studied with CNAP(R) in addition to standard monitoring (NIBP, ECG and oxygen saturation). All monitoring values were extracted from the surveillance network at one-second intervals, and clinical parameters were documented. The variance of CNAP values were calculated for every interval between two NIBP measurements.

RESULTS

2660 minutes of monitoring were recorded (mean 60.1+/-34.4 min/patient). All patients were analgosedated with midazolam and pethidine, and 24/40 had propofol infusion (mean 90.9+/-70.3 mg). The mean arterial pressure for CNAP was 102.4+/-21.2 mmHg and 106.8+/-24.8 mmHg for NIBP. Based on the first NIBP value in an interval between two NIBP measurements, BP values determined by CNAP showed a maximum increase of 30.8+/-21.7% and a maximum decrease of 22.4+/-28.3% (mean of all intervals).

DISCUSSION

Conventional intermittent blood pressure monitoring of patients receiving sedating agents failed to detect fast changes in BP. The new technique CNAP improved the detection of rapid BP changes, and may contribute to a better patient safety for those undergoing interventional procedures.