Abbreviated preoperative fasting favours postoperative oral intake at lower hospital admission costs for cancer patients.

ABSTRACT Objective: to evaluate the feasibility of abbreviated fasting in oncologic colorectal surgeries, as well as the impact on the surgical outcome of the patients. Methods: prospective randomized comparative study with patients undergoing elective colorectal cancer surgeries from May to September 2017. Patients were randomized electronically into two groups according to the preoperative fast to be adopted: conventional or abbreviated. Results: of the 33 patients included, 15 followed the abbreviated fasting protocol and 18 the conventional fasting. Both groups had comparable profiles. No patient underwent mechanical preparation of the colon. In 69.7% of the cases, surgery involved low rectal dissection. The procedures were equivalent in relation to intraoperative variables and severe complications. The time to achieve complete oral intake was shorter for abbreviated fasting (10 versus 16 days, p=0.001), as well as the length of inhospital stay (2 versus 4 days, p=0.009). Hospital costs were lower in the abbreviated fasting (331 versus 682 reais, p<0.001). The univariable analysis revealed a correlation between complete oral intake and abbreviated fasting [HR 0.29 (IC95%: 0.12-0.68] and abdominal distension [HR 0.12 (IC95% 0.01-0.94)]. After multivariable analysis, abbreviated fasting presented a lower time for complete oral intake [HR 0.39 (IC95%: 0.16-0.92]. Conclusion: the abbreviated preoperative fasting favors the metabolic-nutritional recovery, reducing the time for complete oral intake. The implementation of the abbreviation protocol reduces hospital admission costs.