Use of Intravenous Hydroxocobalamin without Methylene Blue for Refractory Vasoplegic Syndrome After Cardiopulmonary Bypass.

BACKGROUND Cardiac vasoplegic syndrome is a form of vasodilatory shock characterized by profound vasodilation and low systemic vascular resistance, which results in significant hypotension despite high cardiac output and appropriate fluid resuscitation. In up to 45% of patients, cardiopulmonary bypass (CPB) can precipitate vasoplegic syndrome. Vasoplegic syndrome after CPB that is refractory to other vasopressors, such as catecholamine and vasopressin, has been successfully treated with inhibitors of the nitric oxide (NO) system, such as methylene blue and hydroxocobalamin. Methylene blue has been the treatment of choice because of its effectiveness for both prevention and rescue therapy. Hydroxocobalamin has demonstrated efficacy in combination with methylene blue, and also on its own when vasoplegic syndrome is refractory to methylene blue. CASE REPORT We present 2 cases that expand upon the existing evidence supporting the efficacy of hydroxocobalamin as a first-line option for inhibiting the NO system in vasoplegic syndrome that is refractory to other vasopressors. Specifically, we demonstrate the appropriate and successful use of hydroxocobalamin alone to treat refractory vasoplegic syndrome after CPB. CONCLUSIONS Refractory vasoplegic syndrome that occurs after CPB has been successfully treated with inhibitors of the NO system, such as methylene blue and hydroxocobalamin. The present cases expand upon the scant existing evidence of the efficacy of hydroxocobalamin as an appropriate option for refractory vasoplegic syndrome.

Risk factors associated with stool retention assessed by abdominal radiography for constipation.

OBJECTIVES: To assess the reliability of applying a radiographic scoring system in estimating the severity of stool retention (SR) in hospitalized older adults with constipation, and to identify risk factors associated with clinical constipation and SR scores. DESIGN: Retrospective, case series study. SETTING: Southeast Ohio community hospital. PARTICIPANTS: Adults 65 years or older with constipation or fecal impaction and abdominal radiographs available (N=122). Bowel obstruction was excluded. MEASUREMENT: Radiographs were independently scored by four readers twice, "5" being the most severe, for each quadrant of an abdominal film; possible total score was 0 to 20. Clinical constipation was defined as an average SR score of 13 or higher. Intra-class correlation was used to measure inter-rater agreement. RESULTS: The overall inter-rater agreement on abdominal radiograph readings was 0.91, 95% confidence interval (CI)=0.88-0.93. Clinical constipation was associated with the use of statins and antimuscarinics by univariate logistic regression analysis. After adjusting for age, sex, residency, smoking history, oral laxatives, and self-reported constipation, the use of statins remained significantly associated with clinical constipation (OR=3.86, 95% CI=1.08-13.77, P=.036). Univariate linear regression analysis revealed that higher SR scores were associated with community residency, self-reported constipation, and the use of statins and antimuscarinics. After adjusting for the above confounders by multiple linear regression analyses, the use of antimuscarinics was independently associated with higher SR score (ß=1.769, 95% CI=0.008-3.531, P=.049). CONCLUSION: Abdominal radiography was reliable in assessing the severity of SR in older adults with constipation. The use of statins and antimuscarinics was associated with clinical constipation and greater SR.