Association of admission serum sodium and outcomes following out-of-hospital cardiac arrest.

BACKGROUND: The prognostic association between dysnatremia and outcomes in out-of-hospital cardiac arrest (OHCA) is not well understood. Given hypernatremia is associated with poor outcomes in critical illness and hyponatremia may exacerbate cerebral edema, we hypothesized that dysnatremia on OHCA hospital admission would be associated with worse neurological outcomes. METHODS: We studied adults (≥19 years) with non-traumatic OHCA between 2009 and 2016 who were enrolled in the British Columbia Cardiac Arrest Registry and survived to hospital admission at 2 quaternary urban hospitals. We stratified cases by admission serum sodium into hyponatremic (<135 mmol/L), normonatremic (135-145 mmol/L), and hypernatremic (>145 mmol/L) groups. We used logistic regression models, adjusted for age, sex, shockable rhythm, admission serum lactate, and witnessed arrest, to estimate the association between admission sodium and favorable neurological outcome (cerebral performance category 1-2 or modified Rankin scale 0-3). RESULTS: Of 414 included patients, 63 were hyponatremic, 330 normonatremic, and 21 hypernatremic. In each respective group, 21 (33.3%), 159 (48.2%), and 3 (14.3%) experienced good neurological outcomes. In univariable models, hyponatremia (OR 0.53, 95% CI 0.30-0.93) and hypernatremia (OR 0.19, 95% CI 0.05-0.65) were associated with lower odds of good neurological outcomes compared to the normonatremia group. After adjustment, only hypernatremia was associated with lower odds of good neurological outcomes (OR 0.22, 95% CI 0.05-0.98). CONCLUSIONS: Hypernatremia at admission was independently associated with decreased probability of good neurological outcomes at discharge post-OHCA. Future studies should focus on elucidating the pathophysiology of dysnatremia following OHCA.

Association between elevated peripheral blood eosinophil count and respiratory outcomes in adults with cystic fibrosis.

BACKGROUND: Elevated blood eosinophil counts are linked to worse outcomes in asthma and COPD, but have yet to be well characterized in CF. We hypothesized that higher stable visit blood eosinophil counts are associated with increased rates of lung function decline and pulmonary exacerbations (PEx). METHODS: We performed a retrospective analysis of adult CF patients (≥19 years) enrolled from 2012 to 2018 in a prospective cohort study focused on blood biomarkers. We included individuals with at least one year of follow-up post-stable visit blood draw and compared clinical characteristics by blood eosinophil count (<300 cells/µL vs. ≥300 cells/µL). We used multivariate mixed-effects linear regression to estimate annual change in ppFEV1. Multivariable poisson and linear regression models were used to estimate rate of PEx requiring IV antibiotics and to compare CF Respiratory Symptom Diary-Chronic Respiratory Infection Symptom Scores (CFRSD-CRISS), respectively. RESULTS: Of 109 patients, 17 (15.6%) had eosinophil counts ≥300 cells/µL. After adjustment for age, sex, BMI, and baseline ppFEV1, there was no association between high vs. low eosinophil group and rates of lung function decline (difference in slope -0.04%/y; 95% CI -1.5 to +1.4) or rates of PEx requiring IV antibiotics (IRR 1.46; 95% CI 0.75 to 2.65). The high eosinophil group had a higher mean CFRSD-CRISS score at stable visit (adjusted mean difference 9.3; 95% CI 2.9 to 16.0). CONCLUSIONS: The high eosinophil group experienced increased respiratory symptoms, but the rates of lung function decline and PEx were comparable between groups.