Clinical value of the Integrated Pulmonary Index® during sedation for interventional upper GI-endoscopy: A randomized, prospective tri-center study

BACKGROUND AND STUDY AIMS

The Integrated Pulmonary Index^® (IPI) is a mathematically-determined factor based on parameters of capnography and pulse oximetry, which should enable sensitive detection of impaired respiratory function. Aim was to investigate whether an additional measurement of the IPI during sedation for interventional endoscopy, compared to standard monitoring alone, allows a reduction of sedation-related respiratory depression.

PATIENTS AND METHODS

170 patients with standard monitoring randomly underwent either a blinded recording of capnography (control group, n=87) or capnography, including automated IPI calculation (IPI group, n=83), during deep sedation with midazolam and propofol. The primary endpoint was the maximum decrease of oxygen saturation from the baseline level before sedation. Secondary endpoints: incidence of hypoxemia (SaO₂<90%), other sedation-related complications (apnea rate, bradycardia, hypotension), patient cooperation and satisfaction (VAS).

RESULTS

Mean propofol dose in the IPI group (245±61mg) was comparable to the control group (225±47mg). The average drop of the oxygen saturation in the IPI group (6.5±4.1%) was nearly identical to that of the control group (7.1±4.6%, p=0.44). Apnea episodes >15s was found in 46 patients of the control and 31 of the IPI group (p<0.05). Frequency of occurrence of a drop in pO₂-saturation <90%, bradycardia <50/min or a drop of systolic pressure <90mmHg were not significantly different in both groups. Mechanical ventilation was not required in any case. Patient cooperation and satisfaction were assessed similar in both groups.

CONCLUSION

A clinically appealing advantage of IPI-assessment during deep sedation with midazolam and propofol for interventional endoscopy could not be documented. However, IPI registration was more effective in reducing the incidence of apnea episodes.

Capnographic monitoring of midazolam and propofol sedation during ERCP: a randomized controlled study (EndoBreath Study)

BACKGROUND AND STUDY AIMS

This was to determine whether intervention based on additional capnographic monitoring reduces the incidence of hypoxemia during midazolam and propofol sedation for endoscopic retrograde cholangiopancreatography (ERCP).

METHODS

Patients (American Society of Anesthesiologists [ASA] I – IV) scheduled for ERCP under midazolam and propofol sedation were randomly assigned to a control arm with standard monitoring or an interventional arm with additional capnographic monitoring. In both arms detection of apnea prompted withholding of propofol administration, stimulation of the patient, insertion of a nasopharyngeal tube, or further measures. The primary study end point was incidence of hypoxemia (oxygen saturation [Sao 2] below 90 %); secondary end points included occurrences of severe hypoxemia (Sao 2 ≤ 85 %), bradycardia, and hypotension, and sedation quality (patient cooperation and satisfaction).

RESULTS

242 patients were enrolled at three German endoscopy centers. Intention-to-treat analysis revealed no significant reduction in hypoxemia incidence in the capnography arm compared with the standard arm (38.0 % vs. 44.4 %, P = 0.314). Apnea was more frequently detected in the capnography arm (64.5 % vs. 6.0 %, P < 0.001). There were no differences regarding rates of bradycardia and hypotension. Per-protocol analysis showed lower incidence of hypoxemia in the capnography arm compared with the standard arm (31.5 % vs. 44.8 %, P = 0.048). There was one death related to sedation in the standard arm. Sedation quality was similar in the two groups.

CONCLUSION

Intention-to-treat analysis showed hypoxemia incidence was not significantly lower in the additional capnography arm compared with standard monitoring. Additional capnographic monitoring of ventilatory activity resulted in improved detection of apnea.

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.