Photoplethysmography respiratory rate monitoring in patients receiving procedural sedation and analgesia for upper gastrointestinal endoscopy

Abstract

The value of capnography during procedural sedation and analgesia (PSA) for the detection of hypoxaemia during upper gastrointestinal (UGI) endoscopic procedures is limited. Photoplethysmography respiratory rate (RRp) monitoring may provide a useful alternative, but the level of agreement with capnography during PSA is unknown. We therefore investigated the level of agreement between the RRp and capnography-based RR (RRc) during PSA for UGI endoscopy. This study included patients undergoing PSA for UGI endoscopy procedures. Pulse oximetry (SpO2) and RRc were recorded in combination with Nellcor 2.0 (RRp) monitoring (Covidien, USA). Bland–Altman analysis was used to evaluate the level of agreement between RRc and RRp. Episodes of apnoea, defined as no detection of exhaled CO2 for minimal 36 s, and hypoxaemia, defined as an SpO2 < 92 %, were registered. A total of 1054 min of data from 26 patients were analysed. Bland–Altman analysis between the RRc and RRp revealed a bias of 2.25 ± 5.41 breath rate per minute (brpm), with limits of agreement from −8.35 to 12.84 brpm for an RR ≥ 4 brpm. A total of 67 apnoea events were detected. In 21 % of all apnoea events, the patient became hypoxaemic. Hypoxaemia occurred 42 times with a median length of 34 (19–141) s, and was preceded in 34 % of the cases by apnoea and in 64 % by an RRc ≥ 8 brpm. In 81 % of all apnoea events, photoplethysmography registered an RRp ≥ 4 brpm. We found a low level of agreement between capnography and the plethysmography respiratory rate during procedural sedation for UGI endoscopy. Moreover, respiratory rate derived from both the capnogram and photoplethysmogram showed a limited ability to provide warning signs for a hypoxaemic event during the sedation procedure.

Contact-Based Methods for Measuring Respiratory Rate

“…PPG measurement for fR estimation has been tested on patients in clinical settings during procedural sedation and analgesia: in [252] the PPG sensor on the finger showed a limited ability to provide warning signs for a hypoxemic event during the sedation procedure (bias of 2.25 ± 5.41 bpm in the absence of movements). However, a recent multi-center study demonstrated that PPG sensor signals can be used for QB monitoring on healthy subjects and hospitalized patients with a bias always lower than 0.07 ± 3.90 bpm when compared to fR reference data (gathered by capnography [253]).…”

The Importance of Respiratory Rate Monitoring: From Healthcare to Sport and Exercise

“…One of the exceptions is the Nellcor TM Respiratory Rate Software application (Medtronic, Dublin, Ireland), which showed a good performance when tested in hospitalized patients against the capnography reference method (Mean of difference, MOD ± Limits of agreement, LOAs, 0.07 ± 3.90 breaths/min) [127]. Conversely, lower performances were found in the challenging measurement scenario of patients undergoing sedation and analgesia for endoscopy procedures, with a substantial difference observed between the f R estimated from PPG with the Nellcor TM 2.0 monitoring system (Covidien, Mansfield, MA, USA) and that obtained from capnography (MOD ± LOAs, 2.25 ± 10.60 breaths/min) [128]. Cardiac arrhythmias may also affect the physiological mechanisms responsible for the respiratory modulation of the PPG signal, and thus the quality of f R measurement [62].…”

<p>A pilot study of respiratory rate derived from a wearable biosensor compared with capnography in emergency department patients</p>

“…Further, it is not feasible to obtain frequent respiratory rate measurements in busy clinical settings, such as the emergency department. The gold standard for monitoring respiratory rate in patients who are intubated and patients in perioperative setting is via capnography 8,9. However, it may not be practical to apply a nasal cannula on every patient in the emergency department, as it limits movement and may be uncomfortable to wear.…”

“…Although capnography is regarded as the gold standard for monitoring respiratory rate in intubated and perioperative patients,8,9 there is no gold standard for monitoring respiratory rate in patients who are awake and mobile. Capnography monitoring requires that the patient wear a nasal cannula connected to a capnograph that derives a respiratory rate,2 which limits patient mobility.…”