Paul S Chan’s research while affiliated with St. Luke's Health System, Idaho and other places

Background Contemporary research in peripheral artery disease (PAD) remains limited due to lack of a national registry and low accuracy of diagnosis codes to identify patients with PAD. Methods Leveraging a novel natural language processing system that identifies PAD with high accuracy using ankle‐brachial index and toe‐brachial index values, we created a registry of 103 748 patients with new‐onset PAD in the Veterans Health Administration. Study end points include mortality, cardiovascular events (hospitalization for acute myocardial infarction or stroke) and limb events (hospitalization for critical limb ischemia or major amputation) and were identified using Veterans Affairs and non–Veterans Affairs encounters. Results The mean age was 70.6 years; 97.3% were male, and 18.5% self‐identified as Black. The mean ankle‐brachial index value was 0.78 (SD: 0.26) and the mean toe‐brachial index value was 0.51 (SD: 0.19). A majority of patients were current (27.1%) or former (30.0%) smokers. Prevalence of hypertension (86.6%), heart failure (22.7%), diabetes (54.8%), chronic kidney disease (23.6%), and chronic obstructive pulmonary disease (35.4%) was high. At 1 year, 9.4% of patients had died. The 1‐year incidence of cardiovascular events was 5.6 per 100 patient‐years and limb events was 7.0 per 100 patient‐years. Conclusions We have successfully launched a registry of >100 000 patients with a new diagnosis of PAD in the Veterans Health Administration, the largest integrated health system in the United States. The incidence of death and clinical events in our cohort is high. Ongoing studies will yield important insights regarding improving care and outcomes in this high‐risk group.

Background Out-of-hospital cardiac arrests (OHCA) increased in the adult population during the COVID pandemic.1,2,3,4,5,6,7,8 Objectives We aimed to determine if OHCAs increased in the pediatric population during the COVID pandemic and whether the pandemic exacerbated pre-existing racial and socio-economic disparities.13,17,18,19,20 Methods Utilizing data from 2015 to 2020 from the Cardiac Arrest Registry to Enhance Survival (CARES) database, 13,513 pediatric OHCAs were analyzed. Age categories included infants (0–<1 year), children (1–12 years) and adolescents (13–18 years). This included information on patient demographics, use of CPR (cardiopulmonary resuscitation) or AED (automatic external defibrillator), outcomes, COVID prevalence, and socioeconomic variables. Results In the pediatric population, there was no increase in OHCAs during the COVID pandemic, however in the adolescent population there was an increase in OHCA incidence from 0.29 to 0.40 arrests per 1 million total residents (p < 0.0001), and a decrease in the infant population from 0.861 to 0.803 events per 1 million total residents (p = 0.02). The pandemic worsened the burden of OHCAs in communities with lower socioeconomic status and in which COVID was more prevalent. Disparities of CPR or AED use and survival outcomes were seen based on race, sex, and socioeconomic factors, however none of these disparities were further augmented by the COVID pandemic. Conclusions Adolescent populations showed higher rates of OHCAs during the COVID pandemic, especially in areas with higher COVID incidence. Infants, however, had slightly decreased rates, which may be related to changes in other respiratory infections, and parental behavioral changes during the pandemic.

Introduction Published data investigating a time-dependent effect of initiation of antiarrhythmic therapy for shockable in-hospital cardiac arrest (IHCA) is lacking. We aimed to evaluate the association between time of intravenous amiodarone or lidocaine administration and return of spontaneous circulation (ROSC) in patients with IHCA caused by ventricular fibrillation (VF) or pulseless ventricular tachycardia (pVT). Methods This was a retrospective, multi-center, single health system, observational cohort study of patients with an IHCA caused by VF/pVT and who received amiodarone or lidocaine during 2014–2024. The primary outcome was ROSC, and the secondary outcome was survival to hospital discharge. A multivariable logistic regression model was constructed to evaluate the association between (1) time to drug administration and (2) drug administration prior to the second defibrillator shock on both survival outcomes. Results A total of 88 patients with a shockable IHCA were identified. Longer time to amiodarone or lidocaine administration was associated with lower likelihood of ROSC (adjusted odds ratio [aOR] 0.91; 95% CI: 0.83–0.99, P = 0.04) but not with survival to discharge (aOR 0.99; CI 0.90–1.10P = 0.90). Administration of antiarrhythmic therapy prior to the second defibrillator shock was associated with higher likelihood of ROSC (aOR 6.48; CI 2.08–20.21, P = 0.001) and survival to discharge (aOR 2.82; CI 1.03–7.77, P = 0.04). Conclusion Early administration of amiodarone or lidocaine, particularly prior to the second defibrillator shock, was associated with an increased odds of survival outcomes in IHCA with shockable rhythms.

Background Nursing home residents are typically excluded in studies of out-of-hospital cardiac arrest (OHCA). Since nursing homes have on-site healthcare staff, cardiopulmonary resuscitation (CPR) and use of an automated external defibrillator (AED) for OHCA would ideally be 100% before arrival of 9-1-1 emergency responders. However, little is known about healthcare provider bystander response and the degree of variability in initiating CPR and AED use in nursing homes. Methods Within the U.S. CARES registry, we identified 71,530 adults at nursing homes who had resuscitation initiated for OHCA between 2013–2021. We assessed rates of bystander CPR and AED application by nursing home healthcare staff. Using multivariable hierarchical logistic regression, we quantified variation in healthcare provider bystander CPR and AED application rates using the median odds ratio (OR), which estimates the difference in odds that 2 similar patients with OHCA would receive healthcare provider bystander CPR or have an AED applied at two randomly selected nursing homes. Results Mean age was 74 ± 13 years and 53.5% were men. Overall, 58,814 (82.2%) patients received healthcare provider bystander CPR and 20,302 (28.4%) had an AED applied. Among 4014 nursing homes with ≥5 OHCAs (n = 42,399), the median OR for healthcare provider bystander CPR was 2.13 (95% CI: 2.05–2.22) and the median OR for healthcare provider bystander AED application was 4.54 (95% CI: 4.31–4.76), both suggesting several-fold variation in treatment across nursing homes. Conclusion In U.S. nursing homes, healthcare provider bystander CPR and AED application rates were not ideal, with large variation in both rates across sites.