Is Activity Tracker-Measured Ambulation an Accurate and Reliable Determinant of Postoperative Quality of Recovery? A Prospective Cohort Validation Study.

BACKGROUND: Quality of recovery (QOR) instruments measure patients' ability to return to baseline health status after surgery. Whether, and the extent to which, postoperative ambulation contributes to QOR is unclear, in part due to the lack of valid tools to measure ambulation in clinical settings. This cohort study of the cesarean delivery surgical model examines the accuracy and reliability of activity trackers in quantifying early postoperative ambulation and investigates the correlation between ambulation and QOR. METHODS: A prospective cohort of 200 parturients undergoing cesarean delivery between July 2015 and June 2017 was fitted with wrist-worn activity trackers immediately postpartum. The trackers were collected 24 hours later, along with QOR assessments (QoR-15 scale). The relationship between QOR and various covariates, including ambulation, was explored using multivariable linear regression and Spearman correlation (ρ). Forty-eight parturients fitted with 2 trackers also completed a walk exercise accompanied by a step-counting assessor, to evaluate accuracy, inter-, and intradevice reliability using interclass correlation (ICC). RESULTS: Compared to step counting, activity trackers had high accuracy (ICC = 0.93) and excellent inter- and intradevice reliability (ICC = 0.98 and 0.96, respectively). Correlation analysis suggested that early ambulation is moderately correlated with postcesarean QoR-15 scores, with a ρ (95% confidence interval) equivalent to 0.56 (0.328-0.728). Regression analysis suggested that ambulation is a determinant of postcesarean QoR-15 scores, with an effect estimate (95% confidence interval) equivalent to 0.002 (0.001-0.003). Ambulation was also associated with all QoR-15 domains, except psychological support. The patient's acceptable symptom state (subjective threshold for good ambulation) in the first 24 hours was 287 steps. CONCLUSIONS: This study demonstrated the accuracy and reliability of activity trackers in measuring ambulation in clinical settings and suggested that postoperative ambulation is a determinant of postoperative QOR. A hypothetical implication of our findings is that interventions that improve ambulation may also help to enhance QOR, but further research is needed to establish a causal relationship.

A comparison of sevoflurane-propofol versus sevoflurane or propofol for laryngeal mask airway insertion in adults.

In a prospective, randomized study, we investigated the incidence of successful insertion of laryngeal mask airway (LMA) at the first attempt and the incidence of side effects after LMA insertion using the combination of sevoflurane and propofol as compared with either sevoflurane or propofol alone for induction of anesthesia. Eighty-three unpremedicated ASA physical status I-II patients were anesthetized with a single vital capacity breath (VCB) of sevoflurane 8% supplemented with IV propofol 1.5 mg/kg, a single VCB of sevoflurane 8%, or IV propofol 3 mg/kg. The coinduction technique was associated with the most frequent incidence of successful LMA insertion at the first attempt (93.5%) than either sevoflurane alone (46%) or propofol alone (61.5%) (P < 0.001). Propofol-induced induction of anesthesia allowed the fastest insertion of LMA and was associated with the least frequent incidence of postoperative nausea and vomiting. However, this advantage of propofol was offset by a frequent incidence of pain on injection (69%) and the occurrence of movements during insertion of the LMA (50% in the propofol group versus 19% and 26% in the sevoflurane and sevoflurane-propofol groups, respectively; P < 0.05), as well as a more frequent incidence of apnea (84% in the propofol group versus 7% and 16% in the sevoflurane and sevoflurane-propofol groups, respectively; P < 0.001). The report shows that induction of anesthesia with sevoflurane-propofol combined provides a frequent incidence of successful LMA insertion at the first attempt that is associated with an infrequent incidence of apnea.

Oxygenation using tidal volume breathing after maximal exhalation.

UNLABELLED: We compared, in volunteers, the oxygenation achieved by tidal volume breathing (TVB) over a 3-min period after maximal exhalation with that achieved by TVB alone. Twenty-three healthy volunteers underwent the two breathing techniques in a randomized order. A circle absorber system with an oxygen flow of 10 L/min was used. The end-expiratory oxygen concentration (EEO(2)) was monitored at 15-s intervals up to 3 min. TVB after maximal exhalation produced EEO(2) values of 68% +/- 5%, 75% +/- 5%, and 79% +/- 4% at 30, 45, and 60 s, respectively, which were significantly larger (P < 0.05) than the corresponding values obtained with TVB alone (58% +/- 5%, 66% +/- 6%, and 71% +/- 5%, respectively). In both techniques, the EEO(2) increased exponentially, with time constants of 35 s during TVB after maximal exhalation versus 58 s during TVB without prior maximal exhalation. In conclusion, maximal exhalation before TVB can hasten preoxygenation by decreasing the nitrogen content of the functional residual capacity, with a consequent increase of EEO(2) to approximately 70% in 30 s and 80% in 60 s. IMPLICATIONS: Oxygenation by using maximal exhalation before tidal volume breathing produced a significantly faster increase in end-expiratory oxygen concentration than oxygenation with tidal volume breathing alone.