Research Highlights Clinical Benefits of 2–4 Hour Fluid Fasting Protocols in Surgery Patients

Can Shorter Preoperative Fasting Transform Your OR Outcomes?

Imagine your next elective surgical patient, anxious and thirsty after a long fast—could a simple protocol change improve both their experience and your hospital’s efficiency? The latest multicenter study published in Anesthesia & Analgesia suggests that reducing preoperative fluid fasting to 2–4 hours can significantly impact postoperative recovery and resource utilization.

Study Design: Retrospective Multicenter Analysis

This robust analysis included 15,837 adult patients from four hospitals in Denmark and Turkey, all part of the Safe Brain Initiative (SBI). The research team retrospectively examined data focusing on fluid fasting times (FFT) before surgery and their association with key clinical outcomes. The SBI care bundle encouraged teams to reduce clear fluid fasting to 2 hours, in line with international guidelines. Patients were grouped into “short” (2–4 hours) and “long” (5–24 hours) fasting cohorts after outlier exclusion.

Key Findings: Shorter Fasting Means Better Outcomes

Median preoperative FFT was 5 hours, yet only 40% achieved the recommended 2–4 hour window.

Short FFT adherence improved over time with targeted education and monitoring.

Compared to long fasting, patients with short FFT experienced:

Lower rates of postoperative delirium (4.3% vs 6.0%)

Median hospital stays reduced by 18 hours

Better patient-reported outcomes: less thirst, pain, nausea, and anxiety postoperatively

Notably, the risk of delirium—a common complication in the post-anesthesia care unit (PACU)—was significantly decreased with shorter fasting, even after accounting for age, ASA status, anesthesia type, and surgery duration.

Implementation: What Drove Adherence?

Sustained improvements came from multilayered interventions: regular staff education, real-time feedback via dashboards, patient information materials, and ongoing team discussions. One site that layered these strategies achieved the most pronounced gains, demonstrating the power of a coordinated, multidisciplinary approach.

Clinical Implications: Why This Matters for Your Practice

Prolonged fluid fasting is still common—often due to ingrained habits, communication gaps, or scheduling unpredictability. This study shows that shorter preoperative fasting is both feasible and beneficial when teams commit to protocol-driven practice change. The result? Improved patient comfort, fewer complications, and shorter, more efficient hospitalizations.

Technical note: “Postoperative delirium (POD)” refers here to acute confusion detected in the recovery room, measured via the Nursing Delirium Screening Scale.

Conclusion

Shortening preoperative fluid fasting to 2–4 hours before elective surgery isn’t just a guideline—it’s a proven way to enhance recovery, reduce complications, and make better use of hospital resources. Empower your teams and patients with this evidence-based, patient-centered change.

Key points

Short fasting (2–4 hours) before surgery reduced delirium risk and shortened hospital stays by 18 hours.

Only 40% of patients achieved optimal fluid fasting times, but adherence improved with focused interventions.

Shorter fasting improved patient comfort, reducing thirst, pain, nausea, and anxiety.

Multidisciplinary staff education and feedback systems were critical for successful protocol adoption.

Implementing short fasting times can enhance patient safety, satisfaction, and hospital efficiency.

Citation: Bubser F, Jakobsen K, Meco BC, et al. Impact of Shorter Preoperative Fluid Fasting on Patient Outcomes: A Safe Brain Initiative Retrospective Cohort Analysis. Anesthesia & Analgesia. 2026;142:1101–1110. DOI: 10.1213/ANE.0000000000007817