Liberal preoperative fasting policy tied to reduced fasting duration and improved patient well-being
Preoperative fasting is commonly implemented to minimize the risk of aspiration in patients undergoing elective procedures under anesthesia. In adults, guidelines advise withholding solids for 6 hours and clear fluids for 2 hours before anesthesia. Studies have shown that guideline implementation is suboptimal: in many hospitals, patients still fast 5 to 6 hours for clear fluids, leading to negative metabolic sequelae. Inadequate implementation is, among other things, caused by fear of aspiration, anxiety, and loose flexibility in operating room scheduling.
Recent studies, mainly in children, have shown that reducing fluid fasting times results in flexible operating room scheduling, reduced postoperative nausea and vomiting (PONV) and better patient well-being, without increasing aspiration risk.
In response to these studies, European pediatric fasting guidelines relaxed their recommendations to allow intake of clear fluids until 1 hour before anesthesia. An international consensus statement on procedural sedation advises liberal clear fluid intake in adults considered at low risk for regurgitation.
Based on these considerations, Marsman M and team implemented a liberal fasting policy for clear fluids in adults scheduled for procedures under anesthesia. This prospective study evaluated the implementation of this liberal policy, by studying the change in fasting duration. Authors also aimed to assess the safety of this liberal fasting policy with regard to regurgitation and aspiration. Finally, they studied if fasting duration was related to patient well-being (thirst and PONV).
This was a quality improvement study conducted from January 2016 to July 2021 at a tertiary referral hospital in the Netherlands. Adults scheduled for nonemergency procedures under anesthesia were included in the study. Patients undergoing obstetrics procedures or those who were intubated preoperatively were excluded. Stepwise introduction of a liberal fluid fasting policy, allowing for ingestion of clear fluids until arrival at the operating room. The primary outcome was change in fasting duration. Secondary outcomes were patient well-being, measured as preoperative thirst, amount of fluid ingested, postoperative nausea and vomiting (PONV), and administration of antiemetics. Safety was measured as incidence of regurgitation and aspiration (pneumonia).
Of the 76451 patients included in the study, 59036 (78%) followed the standard policy, and 16815 (22%) followed the liberal policy. Time series analysis showed an estimated fasting duration decrease of 3:07 hours (P < .001) after implementation of the liberal policy. Post implementation median (IQR) fasting duration was 1:20 (0:48-2:24) hours. The incidence of regurgitation changed from 18 to 24 in 10 000 patients, and the incidence of aspiration changed from 1.7 to 2.4 in 10 000 patients. In the liberal policy, thirst feelings decreased (37% vs 46%; P < .001). PONV incidence decreased from 10.6% to 9.4% (P < .001) and antiemetic administration decreased from 11.0% to 9.5% (P < .001).
This was a quality improvement study of the implementation of a liberal fasting policy that allowed adults scheduled for procedures under anesthesia to drink clear fluids until arrival in the operating room. Time series analysis showed an associated estimated decrease in fasting duration of 3:07 hours to a median post implementation duration of 1:10 hours, and 75% of patients had a fasting duration of 2:24 hours or shorter, suggesting implementation success. The liberal policy was associated with improved patient wellbeing as patients felt less thirsty. Authors also found a small decrease in PONV and antiemetics administration in minor surgery. The incidence of regurgitation was 24 in 10 000 patients after implementation, compared with 18 in 10 000 patients before implementation. Inferiority of the liberal policy with regard to safety could not be ruled out.
Results of this quality improvement study suggest that a liberal fasting policy was associated with a clinically relevant reduction in fasting duration and improved patient well-being with regard to preoperative thirst and PONV. Although a slightly higher incidence of regurgitation could not be ruled out, wider implementation of such a policy may be advocated, as results are still within the clinically accepted risks margins. Results suggest that surgical procedures in patients who drink clear fluids within 2 hours before anticipated anesthesia should not be postponed or cancelled. To obtain definitive estimates on safety outcomes, there is need for collaborative multicenter studies evaluating a liberal fluid fasting policy.
Source: Marsman M, Kappen TH, Vernooij LM, van der Hout EC, van Waes JA, van Klei WA. Association of a Liberal Fasting Policy of Clear Fluids Before Surgery With Fasting Duration and Patient Well-being and Safety. JAMA Surg. Published online January 04, 2023. doi:10.1001/jamasurg.2022.5867
