Daily Anesthesiology Research Analysis

BACKGROUND: There is no universal objective measure of the effect of sedation on brain activity and how to differentiate it from sleep. In patients with early acute hypoxemic respiratory failure (AHRF), the authors used the odds ratio product, an electroencephalography (EEG)-based metric used to quantify the sleep-wake continuum. Despite patients behaviorally appearing asleep, the authors observed and quantified novel EEG patterns previously unobserved during natural sleep, and hypothesized that these unnatural EEG patterns (EEG Ups ) reflect the effect of sedation. The objective of the study was to explore the relevance of EEG Ups (never or extremely rarely seen in sleep studies) and their association with sedation at the early phase of AHRF. METHODS: This was a prospective cohort study including patients mechanically ventilated for AHRF and Pa o2 /fraction of inspired oxygen less than 200 mmHg receiving various sedation-opioid regimens and doses as per clinical indication. Continuous EEG monitoring was performed from study inclusion until extubation, death, or up to 7 days. EEG quantified the relative power of each frequency band (slow delta, fast delta plus theta, alpha-sigma, beta) and determined the frequency of EEG Ups . RESULTS: A total 1,832 h of EEG recordings were analyzed (mean ± SD, 43 ± 25 h/patient) from 23 patients (median [interquartile range, 25 to 75%], 58 [48 to 70] yr; 87% male; Pa o2 /fraction of inspired oxygen, 150 [116 to 198] mmHg; intensive care unit mortality, 22%). EEG Ups accounted for 42% of the total recording time overall, differed among drug combinations, and exceeded 50% with some sedation-opioid combinations. Brief wake intrusions, a marker of physiologic sleep, were extremely low. EEG Ups prevalence was higher with sedation-opioid combinations ( P ≤ 0.029), high sedation dose ( P ≤ 0.035), and deeper clinical sedation score ( P ≤ 0.024), and was associated with intensive care unit mortality ( P < 0.001). CONCLUSIONS: Continuous intravenous sedation results in EEG Ups that are not present in natural sleep, correlate with dose of sedation, clinical sedation score, and clinical outcomes.

BACKGROUND AND OBJECTIVES: Asthma is the most common chronic disease in children. Difficulty in diagnosis can lead to decreased quality of life and increased morbidity and mortality. Children with asthma have increased intraoperative bronchospasm; however, it is unclear whether intraoperative bronchospasm predicts future asthma. We explored intraoperative bronchospasm and subsequent asthma diagnosis. METHODS: We retrospectively analyzed 44,284 children aged 2-18 years who underwent non-cardiac surgery under general anesthesia between 2014 and 2020. We collected demographic and peri-operative data, including the occurrence of bronchospasm. We then conducted a subgroup analysis of 35 770 patients that received positive pressure ventilation, using logistic regression to assess the relationship between bronchospasm and airway pressures. The association of bronchospasm and subsequent asthma diagnosis was estimated using generalized estimating equations. RESULTS: Intraoperative bronchospasm occurred in 128 patients (0.3%) and was associated with increased risk of asthma (OR 2.29, 95% CI 1.10-4.74, p = 0.03). Asthma was diagnosed in 1238 patients (2.8%); 8 had intraoperative bronchospasm (8 of 1238, 0.7%). After adjustment for confounders, male sex (OR 1.57, 95% CI 1.39-1.76, p < 0.001) and younger age (OR 0.96, 95% CI 0.94-0.97, p < 0.001) were also associated with future asthma diagnosis. In the subgroup analysis, Mean PIP (OR 1.50, 95% CI 1.30-1.74, p < 0.001) was associated with asthma. CONCLUSIONS: This study shows intraoperative bronchospasm is associated with an increased risk of future asthma in children. Enhanced collaboration between pediatric anesthesiologists and pediatricians, and further research, is essential to improve asthma detection, risk stratification, and overall care for pediatric patients.

BACKGROUND: Photoplethysmography has been used to assess vital signs since the late 19th century. Recently, camera-based photoplethysmography systems have gained attention due to their noninvasive nature. However, challenges such as low perfusion, motion artifacts, and ambient light interference limit their use during surgical anesthesia. This study evaluated the efficacy of a camera-based system (FaCare) compared with that of a conventional contact monitor (GE HealthCare CARESCAPE B850 patient monitor) in measuring heartbeat intervals during various stages of surgical anesthesia. METHODS: Thirty patients undergoing video-assisted thoracic surgery were included. Data were collected using a webcam and FaCare software at 4 stages: preanesthesia, postanesthesia, postanesthesia with a shadowless lamp, and postsurgery. Six remote photoplethysmography techniques using artificial intelligence algorithms processed the data. RESULTS: The results demonstrated a high level of agreement between the FaCare and GE HealthCare monitor. Pearson correlation analysis, Bland-Altman plots, and Welch's t test indicated that 88.1% of the heart rate correlation coefficients between the 2 devices were >0.8. Furthermore, their heartbeat interval measurements showed strong agreement in the Bland-Altman plots. FaCare showed comparable functionality, offering a noninvasive alternative suitable for operating rooms. CONCLUSIONS: This study evaluated the FaCare camera-based photoplethysmography system, integrating 6 remote photoplethysmography techniques with artificial intelligence algorithms, and compared it to a conventional contact monitor for measuring heartbeat intervals during surgical anesthesia. The results showed strong consistency between FaCare and the GE contact monitor across different anesthesia stages. These findings indicate that the noninvasive FaCare system reduces infection risks and improves patient comfort. Future research is recommended to optimize artificial intelligence algorithms, data synchronization, and sampling frequency to enhance its clinical application.