Preoperative Fasting Guidelines: Where Are We Now? Findings From Current Practices in a Tertiary Hospital

Association between preoperative fasting time and clinical outcomes in surgical patients in a private general hospital

PURPOSE

Surgical patients are routinely subjected to long periods of fasting, a practice that can exacerbate the metabolic response to trauma and impair postoperative recovery. The aim of this study was to evaluate the association between preoperative fasting time and clinical outcomes in surgical patients.

METHODS

An observational, prospective study with a non-probabilistic sample that included patients of both sexes, aged over 18, undergoing elective surgeries. Data were extracted from electronic medical records, and a questionnaire was applied in 48 hours after surgery. Variables related to postoperative discomfort were assessed using an 11-point numeric rating scale.

RESULTS

The sample consisted of 372 patients, and the duration of the surgical event ranged from 30-680 minutes. The incidence of nausea (26.34%) was twice that of vomiting (13.17%) and showed an association with the surgical procedure's size (p = 0.018). A statistically significant difference was observed only between pain intensity and preoperative fasting times for liquids (p = 0.007) and postoperative fasting time (p = 0.08). The occurrence of postoperative complications showed no association with preoperative fasting time (p = 0.850).

CONCLUSIONS

Although no association was observed between preoperative fasting time and surgical complications, it is noteworthy that both recommended and actual fasting time exceeded the proposed on clinical guidelines.

Design Specifications for an Automated System to Deliver Instructions About Preprocedure Fasting

PURPOSE

Many patients undergoing surgical and other medical procedures requiring sedation or anesthesia receive standardized "no eating or drinking after midnight" instructions. This "standardized" instruction does not change regardless of potential alterations in scheduling that result in significant delays in procedure start times. As a result, the duration of preprocedure fasting often far exceeds recommended requirements. A technological solution that automates the delivery of preprocedure fasting instructions to patients would likely improve the patient experience. The purpose of this study was to determine design specifications for the delivery of notifications to patients as part of an automated system.

DESIGN

A qualitative study was conducted with 14 adult participants using the persona-scenario method.

METHODS

Participants worked in groups to create realistic but fictitious personas and scenarios that described how individuals like themselves would interact with an automated preprocedure fasting instruction system. Data generated through the development of the scenarios were analyzed to first identify important themes, which were then interpreted into design specifications.

FINDINGS

Seven women and seven men, aged 25 to 75, developed 9 persona-scenarios, which captured outpatient and inpatient preprocedure fasting experiences, as well as perspectives of individuals who were not comfortable with technology, or those for which English was not the primary spoken language. Most scenarios described preprocedure fasting instructions delivered by an automated bidirectional short message service system. Two major themes were identified as patient priorities, including: (1) enhancing communication between patients and healthcare providers; and (2) the importance of using simple technology so that a greater number of patients with varying degrees of comfort and capabilities would be able to use the system confidently. A corresponding set of proposed design specifications was devised.

CONCLUSIONS

The results of this study provide actionable ways to operationalize patient-centered ideas in the design of an automated preprocedure fasting instruction system.

Liberal Preoperative Fasting in Adults Undergoing Elective Surgery: A Scoping Review Protocol

Background

Prolonged fasting before surgery has negative effects on the physiology and psychology of patients. Preoperative liberal fasting proposes that patients can drink clear liquids before entering the operating theater, challenging the guideline strategy of a two-hour preoperative liquid fast for adults. In recent years, there have been an increasing number of studies on liberal preoperative fasting in adults. However, currently there is no consensus on the safe amount of fluid consumed, adverse effects, or benefits of this new policy.

Objective

This scoping review protocol will map the existing evidence of liberal preoperative fasting in adults undergoing elective surgery for clinical practice, to summarize more scientific evidence to healthcare professionals when providing perioperative care. Methods and Analysis. The methodology will follow the six steps of the Arksey and O'Malley methodological framework and be guided by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Review. A comprehensive search of six databases will be performed from their inception to 31 May 2023 to identify suitable English studies. Two trained investigators will independently screen and extract the data, and any disagreements will be judged by a third investigator. The results of the study will be presented as graphs or tables. Ethics and Dissemination. This scoping review only examines literature in the database, without reference to human or animal studies, and therefore does not require ethical approval. The findings of this scoping review will be published in peer-reviewed journals or presented at conferences. The Registration Number. This scoping review has been registered in the Open Science Framework (https://doi.org/10.17605/OSF.IO/PMW7C).

Association of a Liberal Fasting Policy of Clear Fluids Before Surgery With Fasting Duration and Patient Well-being and Safety

Importance

Current fasting guidelines for procedures under anesthesia are poorly implemented, leading to negative metabolic sequelae. Recent studies in children showed support of liberal clear fluid intake; adult physiology can support clear fluid intake, but implementation studies are lacking.

Objective

To evaluate the successfulness of implementation of a liberal clear fluid policy with regard to fasting duration, well-being, and safety in adults scheduled for anesthesia.

Design, Setting, and Participants

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.

Interventions

Stepwise introduction of a liberal fluid fasting policy, allowing for ingestion of clear fluids until arrival at the operating room.

Main Outcomes and Measures

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).

Results

Of the 76 451 patients (mean [SD] age, 56 [17] years; 39 530 male individuals [52%] 36 921) included in the study, 59 036 (78%) followed the standard policy, and 16 815 (22%) followed the liberal policy. Time series analysis showed an estimated fasting duration decrease of 3:07 hours (IQR, 1:36-7:22; P < .001) after implementation of the liberal policy. Postimplementation median (IQR) fasting duration was 1:20 (0:48-2:24) hours. The incidence of regurgitation changed from 18 (95% CI, 14-21) to 24 (95% CI, 17-32) in 10 000 patients, and the incidence of aspiration changed from 1.7 (95% CI, 0.6-2.7) to 2.4 (95% CI, 0.5-4.7) in 10 000 patients. In the liberal policy, thirst feelings decreased (37% [4982 of 8615] vs 46% [3373 of 7362]; P < .001). PONV incidence decreased from 10.6% (6339 of 59 636) to 9.4% (1587 of 16 815; P < .001) and antiemetic administration decreased from 11.0% (6538 of 59 636) to 9.5% (1592 of 16 815; P < .001).

Conclusions and Relevance

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 canceled.

Effects of liberal oral intake on postoperative outcomes after elective laparoscopic gynaecological surgery: A randomised controlled clinical trial

BACKGROUND

Women are at risk of postoperative nausea and vomiting (PONV) after laparoscopic gynaecological surgery. Traditionally, patients who undergo laparoscopic gynaecological surgery are only allowed to initiate oral intake after return of bowel function, including bowel sounds or passage of flatus or stool. The present study was designed to assess the effect of liberal oral intake immediately after discharge from the post-anaesthesia care unit (PACU) on PONV incidence in patients who underwent elective laparoscopic gynaecological surgery.

METHODS

In total, 174 patients (aged 20-64 years) were randomly assigned to the traditional and liberal groups. In the traditional group, patients were allowed to initiate oral intake 6 h after discharge from the PACU. In the liberal group, patients were allowed oral intake immediately after discharge from the PACU. The primary outcome was the incidence of PONV 48 h after surgery. Secondary outcomes included ileus incidence, total dose of postoperative opiate (sufentanil) use, time to postoperative first flatus (FFL), first out-of-bed mobilisation and the duration of postoperative hospitalisation stay.

RESULTS

Incidence of PONV was not significantly different between both groups (32.18% vs. 33.33%, p = 0.872). Time to FFL in the liberal group was significantly shorter than that in the traditional group (14.82 ± 0.91 h vs. 17.50 ± 0.96 h, p = 0.024). The postoperative pain score at 48 h after surgery was significantly lower in the liberal group than that in the traditional group (2.48 ± 0.17 vs. 3.20 ± 0.19, p = 0.008) without an increase in sufentanil use (89.32 ± 1.02 µg vs. 89.92 ± 1.16 µg, p = 0.702). No ileus occurred in either group. When considering the time of actually return to regular diet, initiating regular diet no more than 6 h after discharge from PACU significantly shortened the time to first out-of-bed mobilisation (11.18 ± 1.01 h vs. 15.05 ± 0.70 h, p = 0.003).

CONCLUSIONS

Our results indicate that liberal oral intake after discharge from the PACU in patients aged 20-64 years who underwent gynaecological surgery is safe and beneficial and supports the rationale for a more liberal diet regime postoperatively.

Current practice of postoperative fasting: results from a multicentre survey in China

OBJECTIVE

A gap between clinical practice and evidence is common. The present multicentre study was designed to explore the actual postoperative fasting practice, including the instructed fasting time from the ward staff and the actual postoperative fasting time.

DESIGN

Multicentre survey.

SETTING

Four tertiary hospitals in Shenzhen City, China.

PARTICIPANTS

A total of 988 patients completed a survey on instructed and actual postoperative fasting.

OUTCOMES

All patients received postoperative instructed fasting time from the ward staff. The median instructed fasting time for fluids from ward staff was 6 hours (IQR, 4-6 hours), and the median instructed fasting time for solid food was also 6 hours (IQR 5-6 hours) after surgery. The actual postoperative fasting time, including fluid and solid food intake, was significantly longer than the time recommended by the ward staff (both p<0.001).

RESULTS

The median time to postoperative first flatus (FFL) was 16.5 hours (IQR 8-25.5 hours), and the median time to postoperative first faeces (FFE) was 41 hours (IQR 25-57 hours). The fasting time was significantly shorter than the time to FFL and the time to FFE, regardless of surgery type or anaesthesia type (all p<0.001). Postoperative nausea and vomiting (PONV) occurred in 23.6% of patients. After surgery, 58.70% of patients reported thirst, and 47.47% reported hunger. No ileus occurred.

CONCLUSION

Approximately half of the patients reported thirst and hunger postoperatively. Patients initiated oral intake earlier than the time to FFL or FFE without increasing serious complications. This study may support the rationale for interventions targeting postoperative oral intake time in future studies.