Early initiation of oral intake on length of hospital stay in postoperative patients admitted to the intensive care unit

Early oral intake is recommended for postoperative recovery. We determined whether early oral intake affects postoperative hospital stay. Using the diagnosis procedure combination system introduced in Japan in 2003, patients were classified into major diagnostic categories (MDC) to determine whether the postoperative start date of oral nutrition reduces the postoperative length of hospital stay. A total of 491 patients (age range,15-94 years; median, 72 years; male = 316; female = 175) were analyzed, or which 341 cases of MDC05 (cardiovascular diseases) and 150 cases of MDC06 (digestive system diseases, liver, biliary, and pancreatic disease) were admitted to the intensive care unit. The patients were divided into 2 groups: the non-elderly group, <65 years old, and the elderly group, ≥65 years old. Multivariate analysis was conducted to identify the factors influencing the length of postoperative hospital stay. Explanatory variables included body mass index (18.5-24.9), geriatric nutritional risk index ≥ 98, C-reactive protein, postoperative start date of enteral nutrition, postoperative start date of oral nutrition, meal intake rate, medical resources, and nutrition and meal guidance. In MDC05 and MDC06, initiating oral intake early postoperatively significantly contributed to reducing the postoperative number of days of hospital stay (MDC05, all; β = 0.256, P < .001, non-elderly; β = 0.440, P < .001, elderly; β = 0.240, P < .001: MDC06, all; β = 0.563, P < .001, non-elderly; β = 0.552, P < .001, elderly; β = 0.528, P < .001). In the non-elderly group of MDC06, a body mass index of 18.5-24.9 influenced the shorter postoperative number of days of hospital stay (β = -0.320, P = .011). Nutritional management to promote early oral intake is crucial for optimizing the duration of hospital stay in postoperative patients admitted to the intensive care unit. This study demonstrated the importance of preadmission nutritional management.