Abdallah, Arbi Ben

Summary Patients with obstructive sleep apnoea are at increased risk of adverse postoperative outcomes, such as cardiac and respiratory complications. It has been hypothesised that obstructive sleep apnoea also increases the risk for postoperative delirium and acute postoperative pain. We conducted a retrospective, observational study investigating the relationship of obstructive sleep apnoea with postoperative delirium and acute postoperative pain severity. Patients were classified as being at high risk for obstructive sleep apnoea if they had been diagnosed with this condition, or if they were positive for more than four factors using the ‘ STOP ‐ BANG ’ screening tool. Adjusted logistic regression was used to investigate the association between obstructive sleep apnoea and postoperative delirium, and multivariable linear regression to study the relationship between obstructive sleep apnoea and postoperative pain severity. The incidence of postoperative delirium was 307 in 1441 patients (21.3%; 95% CI 19.2–23.5%). In unadjusted analysis, high risk for obstructive sleep apnoea was associated with delirium, with an odds ratio (95% CI ) of 1.77 (1.22–2.57; p = 0.003). After adjustment for pre‐specified variables, the association was not statistically significant with odds ratio 1.34 (0.80–2.23; p = 0.27). The mean ( SD ) maximum pain (resting or provoked) reported for the entire cohort was 63.8 (27.9) mm on a 0–100 mm visual analogue scale. High risk for obstructive sleep apnoea was not associated with postoperative pain severity (β‐coefficient 2.82; 95% CI , −2.34–7.97; p = 0.28). These findings suggest that obstructive sleep apnoea is unlikely to be a strong risk factor for postoperative delirium or acute postoperative pain severity.

Background The recent introduction of high‐sensitivity cardiac troponin (hs‐cTn) assays has allowed clinicians to measure hs‐cTn before and after cardiac stress testing, but the hs‐cTn release pattern and potential utility in identifying inducible myocardial ischemia are unclear. We thus conducted a systematic review and meta‐analysis to improve our understanding of hs‐cTn release associated with exercise and pharmacological stress testing. Methods and Results Studies published between January 2008 and July 2016 that reported hs‐cTn change values (high‐sensitivity cardiac troponin T [hs‐cTnT] or high‐sensitivity cardiac troponin I [hs‐cTnI]) in relation to cardiac stress testing were searched and reviewed by 2 independent screeners. Primary outcomes were pooled estimates of absolute and relative hs‐cTn changes after cardiac stress test, stratified by the presence of inducible myocardial ischemia. This meta‐analysis included 11 studies (n=2432 patients). After exercise stress testing, hs‐cTnT increased by 0.5 ng/L or 11% (6 studies, n=406) and hs‐cTnI by 2.4 ng/L or 41% (4 studies, n=365) in patients with inducible myocardial ischemia versus hs‐cTnT by 1.1 ng/L or 18% (8 studies, n=629; P =0.29) and hs‐cTnI by 1.8 ng/L or 72% (4 studies, n=831; P =0.61) in patients who did not develop inducible myocardial ischemia. After pharmacological stress test, hs‐cTnT changed by −0.1 ng/L or −0.4% (6 studies, n=251) and hs‐cTnI by 2.4 ng/L or 32% (2 studies, n=108) in patients with inducible myocardial ischemia versus hs‐cTnT by 0.7 ng/L or 11% (5 studies, n=443, P =0.44) and hs‐cTnI by 1.7 ng/L or 38% (2 studies, n=116; P =0.62) in patients who did not develop inducible myocardial ischemia. Conclusions hs‐cTn rising patterns after exercise and pharmacological stress testing appear inconsistent and comparably small, and do not appear to be correlated with inducible myocardial ischemia.

BACKGROUND: Frailty is an important concept in the care of older adults although controversy remains regarding its defining features and clinical utility. Both the Fried phenotype and the Rockwood deficit accumulation approaches cast frailty as a “burden” without exploring the relative salience of its cardinal markers and their relevance to the patient. New multifactorial perspectives require a reliable assessment of frailty that can validly predict postoperative health outcomes. METHODS: In a retrospective study of 2828 unselected surgical patients, we used item response theory to examine the ability of 32 heterogeneous markers capturing limitations in physical, functional, emotional, and social activity domains to indicate severity of frailty as a latent continuum. Eighteen markers efficiently indicated frailty severity and were then subject to latent class analysis to derive discrete phenotypes. Next, we validated the obtained frailty phenotypes against patient-reported 30-day postoperative outcomes using multivariable logistic regression. Models were adjusted for demographics, comorbidity, type and duration of surgery, and cigarette and alcohol consumption. RESULTS: The 18 markers provided psychometric evidence of a single reliable continuum of frailty severity. Latent class analyses produced 3 distinct subtypes, based on patients’ endorsement probabilities of the frailty indicators: not frail (49.7%), moderately frail (33.5%), and severely frail (16.7%). Unlike the moderate class, severely frail endorsed emotional health problems in addition to physical burdens and functional limitations. Models adjusting for age, sex, type of anesthesia, and intraoperative factors indicated that severely frail (odds ratio, 1.89; 95% confidence interval, 1.42–2.50) and moderately frail patients (odds ratio, 1.31; 95% confidence interval, 1.03–1.67) both had higher odds of experiencing postoperative complications compared to not frail patients. In a 3-way comparison, a higher proportion of severely frail patients (10.7%) reported poorer quality of life after surgery compared to moderately frail (9.2%) and not frail (8.3%) patients ( P < .001). There was no significant difference among these groups in proportions reporting hospital readmission (5.6%, 5.1%, and 3.8%, respectively; P = .067). CONCLUSIONS: Self-report frailty items can accurately discern 3 distinct phenotypes differing in composition and their relations with surgical outcomes. Systematically assessing a wider set of domains including limitations in functional, emotional, and social activities can inform clinicians on what precipitates loss of physiological reserve and profoundly influences patients’ lives. This information can help guide the current discussion on frailty and add meaningful clinical tools to the surgical practice.