Background: Intracranial hemorrhage (ICH) is the most common neurologic complication of reversible cerebral vasoconstriction syndrome (RCVS). In this study, we compared hemorrhagic and non-hemorrhagic RCVS with an aim to evaluate the risk factors and short-term clinical outcomes of hemorrhagic lesions.
Methods: We used the Nationwide Readmissions Database 2016-2017 to identify all hospitalizations due to RCVS. Predictors and clinical outcomes of ICH were analyzed using logistic regression analysis.
Results: Among the total 1834 hospitalizations for RCVS during the study period (mean ± SD age:48.4 ± 15.6 years, female:75.8%), 768 (41.9%) had occurrence of ICH. Patients with ICH were more likely to be female (OR:2.72, 95% CI:1.86-3.97), have a history of hypertension (OR:1.63, 95% CI:1.20-2.22) and cocaine use (OR:3.11, 95% CI:1.49-6.51), and were less likely to have a history of diabetes (OR:0.52, 95% CI:0.32-0.84) and heart failure (OR:0.34, 95% CI:0.14-0.84). Hemorrhagic RCVS was associated with higher odds of cerebral edema (OR:10.71, 95% CI:5.75-19.97), new onset seizure (OR:2.24, 95% CI:1.08-4.61), respiratory failure (OR:2.40, 95% CI:1.37-4.22) and gastrostomy tube placement (OR:3.20, 95% CI:1.07-9.58). Patients with hemorrhagic lesions also had longer length of hospital stay (mean difference 5.5 days), higher hospital charges (mean difference $105,547), and a lower likelihood of discharge to home (OR:0.61, 95% CI:0.43-0.86). There was, however, no significant difference in the in-hospital mortality.
Conclusions: ICH affects nearly 42% of patients with RCVS and is associated with increased rate of other neurologic complications and adverse discharge disposition, thus putting into question the prevailing conception that RCVS is generally a benign disorder with a self-limiting clinical course.
The study measured fibrinogen fluorescence at temperatures between 20 and 80 degrees Celsius across different pH levels.
It was found that raising the temperature from 20 to 40 degrees Celsius did not change the structure of fibrinogen in solutions with pH between 4.5 and 9.3.
However, temperatures between 40 to 50 degrees Celsius caused some structural changes in neutral solutions, and temperatures above 50-55 degrees Celsius led to significant denaturation of the fibrinogen molecule.
