Relationships between orthostatic hypotension and cardiovascular responses to postoperative early mobilization

Abstract

Background: Orthostatic hypotension (OH) is common after surgery and are associated with an increased risk of postoperative morbidity. The influence of OH after cardiothoracic and abdominal surgery has not been well known. We assessed relation to cardiovascular responses during early mobilization and the incidence of OH after cardiothoracic and abdominal surgery. Methods: This prospective observational study consecutively was analyzed data from 500 patients underwent cardiothoracic and abdominal surgery. We investigated between the incidence of OH and the cardiovascular responses from sitting on the edge of the bed to standing during postoperative early mobilization. Further, multivariate logistic regression was performed identify independent factors associated with OH. Results: OH was observed in 192 (39%) patients. The incidence of OH in cardiac, thoracic and abdominal surgery group were 40 (32%), 86 (51%), 66 (32%), respectively. The rate of variability of heart rate (HR) was significant difference between cardiac surgery group and abdominal surgery group (p<0.05).The incidence of OH in thoracic group was higher than abdominal group (Odds ratio; OR 0.439). Male was independently associated with OH (OR 1.534). Conclusions: These results clarified that about 40% patients were having OH during early mobilization after cardiothoracic and abdominal surgery. Type of surgery and gender were identified as independent factor for OH.