Oral Carbohydrate Supplementation Reduces Preoperative Discomfort in Laparoscopic Cholecystectomy

Effects of Preoperative Oral Carbohydrates on Recovery After Laparoscopic Cholecystectomy: A Meta-analysis of Randomized Controlled Trials

PURPOSE

The objective of this meta-analysis was to evaluate the efficacy of administering preoperative oral carbohydrates (CHO) compared to a control treatment in improving postoperative recovery outcomes for patients undergoing laparoscopic cholecystectomy (LC).

DESIGN

A meta-analysis of randomized controlled trials.

METHODS

Through systematic searches in PubMed, Embase, and the Cochrane Library, randomized controlled trials focusing on preoperative oral carbohydrates for patients undergoing LC were collected. Data analysis was conducted using the Revman 5.3 software.

FINDINGS

The meta-analysis incorporated 19 randomized studies, with a total of 1,568 participants. Meta-analysis results indicated that patients receiving CHO reported notably lower postoperative pain compared to those fasting (P = .006) or on placebo (P = .003). Furthermore, a significant reduction in preoperative hunger was observed in the CHO group compared to the controls (P = .002). A notable difference was also identified in the postoperative Homeostasis Model Assessment-IR changes between the CHO and control groups (P = .02). No significant variations were observed in thirst, postoperative nausea and vomiting, insulin level alterations, glucose level changes, duration of hospital stay, or recovery quality.

CONCLUSIONS

Preoperative oral carbohydrates may alleviate hunger and pain, and attenuate postoperative insulin resistance more effectively than either overnight fasting or placebo in patients undergoing LC.

Trends in preoperative carbohydrate load practice: A systematic review

BACKGROUND

The preoperative carbohydrate load (PCL) is intended to improve surgical outcomes by reducing the catabolic state induced by overnight fasting. However, there is disagreement on the optimal PCL prescription, leaving local institutions without a standardized PCL recommendation. Results from studies that do not prescribe PCL in identical ways cannot be pooled to draw larger conclusions on outcomes affected by the PCL. The aim of this systematic review is to catalog prescribed PCL characteristics, including timing of ingestion, percentage of carbohydrate contribution, and volume, to ultimately standardize PCL practice.

METHODS

A comprehensive search was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Randomized controlled trials were included if they studied at least one group of patients who were prescribed a PCL and the PCL was described with respect to timing of ingestion, carbohydrate contribution, and total volume.

RESULTS

A total of 67 studies with 6551 patients were included in this systematic review. Of the studies, 49.3% were prescribed PCL on the night before surgery and morning of surgery, whereas 47.8% were prescribed PCL on the morning of surgery alone. The mean prescribed carbohydrate concentration was 13.5% (±3.4). The total volume prescribed was 648.2 ml (±377).

CONCLUSION

Variation in PCL practices prevent meaningful data pooling and outcome analysis, highlighting the need for standardized PCL prescription. Efforts dedicated to the establishment of a gold standard PCL prescription are necessary so that studies can be pooled and analyzed with respect to meaningful clinical end points that impact surgical outcomes and patient satisfaction.

Preoperative fasting and the risk of pulmonary aspiration-a narrative review of historical concepts, physiological effects, and new perspectives

In the early days of anaesthesia, the fasting period for liquids was kept short. By the mid-20th century 'nil by mouth after midnight' had become routine as the principles of the management of 'full stomach' emergencies were extended to include elective healthy patients. Back then, no distinction was made between the withholding of liquids and solids. Towards the end of the last century, recommendations of professional anaesthesiology bodies began to reduce the fasting time of clear liquids to 2 h. This reduction in fasting time was based on the understanding that gastric emptying of clear liquids is rapid, exponential, and proportional to the current filling state of the stomach. Furthermore, there was no evidence of a link between drinking clear liquids and the risk of aspiration. Indeed, most instances of aspiration are caused by failure to identify aspiration risk factors and adjust the anaesthetic technique accordingly. In contrast, long periods of liquid withdrawal cause discomfort and may also lead to serious postoperative complications. Despite this, more than two decades after the introduction of the 2 h limit, patients still fast for a median of up to 12 h before anaesthesia, mainly because of organisational issues. Therefore, some hospitals have decided to allow patients to drink clear liquids within 2 h of induction of anaesthesia. Well-designed clinical trials should investigate whether these concepts are safe in patients scheduled for anaesthesia or procedural sedation, focusing on both aspiration risk and complications of prolonged fasting.

Pre-operative carbohydrate drink in pediatric spine fusion: randomized control trial

PURPOSE

As rapid discharge protocols for pediatric spine fusion shorten stays, gastrointestinal (GI) complications are uncovered and cause delays in discharge. A pre-operative carbohydrate (CHO) drink has been shown to improve perioperative GI symptoms and functional return but has not been examined in pediatric spine patients. We aimed to determine if a preoperative CHO drink is safe in pediatric spine fusion patients, and if it improves their comfort scores and return of bowel function.

METHODS

We prospectively randomized ASA-1 and -2 pediatric spine fusion patients to either a pre-anesthesia carbohydrate drink 2 h prior to surgery or to a control group (standard 8 h NPO), blinded to surgical team. We documented time to return to flatus, bowel movement, GI symptoms, and comfort scores for 72 h post-operatively or until discharge.

RESULTS

62 patients were randomized. There was no significant differences between the groups' pre-operative characteristics, surgical details, nor post-operative morphine dose equivalents, except for EBL (405 cc control, 340 cc CHO drink, p = 0.044). There were no perioperative complications related to ingestion of the CHO drink. CHO group had a positive trend for earlier return of flatus (21% vs. 3% return at 12 h), and comfort scores for anxiety and abdominal pain, but no statistically significant differences. There was no difference in length of stay or time to first bowel movement.

CONCLUSION

There were no complications related to ingestion of a CHO drink 2 h prior to pediatric spinal fusion surgery. Further studies are needed to develop a study blinded to the participants with larger sample size. Level of evidence I.

Dietary Considerations in Cholecystectomy: Investigating the Impact of Various Dietary Factors on Symptoms and Outcomes

Cholecystectomy is commonly performed to address gallstone diseases, including the development of gallstones, which can lead to symptoms such as nausea, vomiting, and abdominal pain. Bile acids (BAs) produced by the liver are primarily stored and concentrated in the gallbladder (GB). After cholecystectomy, the body's ability to digest lipids is reduced due to the absence of the GB. Post-cholecystectomy syndrome (PCS) can occur when abdominal symptoms manifest after surgery. The purpose of this review is to look at the various effects of different dietary factors on patients undergoing cholecystectomy, how they affect their overall health after surgery, and how they contribute to symptoms of PCS. Some individuals may experience mild discomfort or alterations in bowel patterns, especially after consuming high-fat meals. The findings from the conducted studies suggest that, although dietary changes are a common recommendation, these measures are not sufficiently supported by evidence when it comes to alleviating symptoms and improving outcomes post-cholecystectomy. The studies found that subjects who consumed particular foods, such as processed meat and fried fatty foods, had exacerbated symptoms after cholecystectomy. Further studies are still required to understand the precise food factors that might affect post-surgical symptoms, as well as outcomes, and to develop tailored measures to enhance patient care and long-term prognosis after undergoing cholecystectomy.

A convenient machine learning model to predict full stomach and evaluate the safety and comfort improvements of preoperative oral carbohydrate in patients undergoing elective painless gastrointestinal endoscopy

BACKGROUND AND AIMS

Assessment of the patient's gastric contents is the key to avoiding aspiration incidents, however, there is no effective method to determine whether elective painless gastrointestinal endoscopy (GIE) patients have a full stomach or an empty stomach. And previous studies have shown that preoperative oral carbohydrates (POCs) can improve the discomfort induced by fasting, but there are different perspectives on their safety. This study aimed to develop a convenient, accurate machine learning (ML) model to predict full stomach. And based on the model outcomes, evaluate the safety and comfort improvements of POCs in empty- and full stomach groups.

METHODS

We enrolled 1386 painless GIE patients between October 2022 and January 2023 in Nanjing First Hospital, and 1090 patients without POCs were used to construct five different ML models to identify full stomach. The metrics of discrimination and calibration validated the robustness of the models. For the best-performance model, we further interpreted it through SHapley Additive exPlanations (SHAP) and constructed a web calculator to facilitate clinical use. We evaluated the safety and comfort improvements of POCs by propensity score matching (PSM) in the two groups, respectively.

RESULTS

Random Forest (RF) model showed the greatest discrimination with the area under the receiver operating characteristic curve (AUROC) 0.837 [95% confidence interval (CI): 79.1-88.2], F1 71.5%, and best calibration with a Brier score of 15.2%. The web calculator can be visited at https://medication.shinyapps.io/RF_model/. PSM results demonstrated that POCs significantly reduced the full stomach incident in empty stomach group (p < 0.05), but no differences in full stomach group (p > 0.05). Comfort improved in both groups and was more significant in empty stomach group.

CONCLUSIONS

The developed convenient RF model predicted full stomach with high accuracy and interpretability. POCs were safe and comfortably improved in both groups, with more benefit in empty stomach group. These findings may guide the patients' gastrointestinal preparation.

Randomized controlled trial of liberal vs. standard fasting instructions in percutaneous cardiac procedures

BACKGROUND

Pre-procedural fasting to reduce aspiration risk is usual care prior to surgery requiring anesthesia. Prolonged fasting, however, can result in dehydration and may adversely affect patient experience and outcomes. Previous studies suggest that providing a supplemental beverage to patients undergoing cardiac and a variety of other surgical procedures improves patients' subjective assessment of thirst and hunger and potentially decreases the need for inotrope and vasopressor therapy. Less is known, however, about the effects of ad libitum clear liquids up to 2 h prior to surgery.

METHODS

Adult patients undergoing transcatheter aortic valve replacement (TAVR) or arrhythmia ablation were randomized (1:1) to ad libitum clear liquids up to 2 h prior to their procedure vs. nil per os (NPO) after midnight (control group, usual care). The primary endpoint was a composite satisfaction score that included patient-reported thirst, hunger, headache, nausea, lightheadedness, and anxiousness prior to surgery. The incidence of case-delay was recorded. Intraoperative vasopressor administration, changes in creatinine, anti-emetic use, and hospital length of stay (LOS) were recorded. Safety endpoints including aspiration were assessed.

RESULTS

A total of 200 patients were randomized and 181 patients were included in the final analysis. Overall, 92% of patients were ASA class III or IV and 23% of patients had NYHA class III or IV symptoms. Groups were well balanced with no significant differences in age, sex or baseline cardiac or renal disease. The composite satisfaction score (primary endpoint) was not significantly different between groups (Ad libitum median = 12, IQR = [6, 17], vs Standard NPO median = 10, IQR = [5, 15], [95% CI = [-1, 4]). No significant differences between the two groups were observed in any of the individual survey questions (thirst, hunger, headache, nausea, lightheadedness, anxiousness). No significant differences between groups were observed for intra-operative vasopressor use, changes in creatinine, rescue anti-emetic use or hospital LOS. There were no case delays attributed to the intervention. There were no cases of suspected aspiration.

CONCLUSION

No adverse events or case delays were observed in the ad libitum clears group. No significant benefit, however, was observed in patient satisfaction or any of the pre-specified secondary endpoints in patients randomized to ad libitum clear liquids up to 2 h prior to their procedure.

TRIAL REGISTRATION

NCT04079543.

Effect of Oral Carbohydrate Solution Administered Before Hip Arthroplasty on Preoperative Anxiety and Postoperative Patient Comfort: A Randomized Controlled Trial

PURPOSE

This study aimed to determine the effect of oral carbohydrate solution (OCS) administered before hip arthroplasty (HA) on preoperative anxiety and postoperative patient comfort.

DESIGN

The study was a randomized controlled clinical trial.

METHODS

Fifty patients undergoing HA were randomized into two groups: The intervention group (n = 25) received OCS before surgery, and the control group (n = 25) fasted from midnight till surgery. The patients' preoperative anxiety was assessed using the State-Trait Anxiety Inventory (STAI), symptoms affecting postoperative patient comfort parameters using the Visual Analog Scale (VAS), and comfort levels specific to HA surgery using the Post-Hip Replacement Comfort Scale (PHRCS). Pre- and post-operative blood glucose levels of the patients were measured.

FINDINGS

In intragroup and intergroup assessments, the decrease in the preoperative and postoperative anxiety, pain, thirst, hunger, and nausea/vomiting levels were statistically significant (P < .05) in the OCS group. The OCS group's comfort levels specific to hip replacement were higher than those of the control group (P ≤ .001). In the intergroup and intragroup assessment of the patients' blood glucose levels, there was a statistically significant difference in favor of the OCS group (P < .05).

CONCLUSIONS

The results of this study provide evidence supporting OCS administration before HA surgery.

2023 American Society of Anesthesiologists Practice Guidelines for Preoperative Fasting: Carbohydrate-containing Clear Liquids with or without Protein, Chewing Gum, and Pediatric Fasting Duration-A Modular Update of the 2017 American Society of Anesthesiologists Practice Guidelines for Preoperative Fasting

These practice guidelines are a modular update of the "Practice guidelines for preoperative fasting and the use of pharmacologic agents to reduce the risk of pulmonary aspiration: Application to healthy patients undergoing elective procedures." The guidance focuses on topics not addressed in the previous guideline: ingestion of carbohydrate-containing clear liquids with or without protein, chewing gum, and pediatric fasting duration.

The clinical effect and safety of new preoperative fasting time guidelines for elective surgery: a systematic review and meta-analysis

BACKGROUND

Traditional fasting and no drinking schemes (fasting for 8-12 hours and no drinking for 4-6 hours) affect the metabolism of the body. The new guidelines put forward by the American Association of Anesthesiologists (fasting for 6 hours, no drinking for 2 hours) obviously reduce the time of fasting and no drinking, but the clinical efficacy and safety need to be further confirmed. In this study, a meta-analysis of randomized controlled trials (RCTs) using the new guidelines and traditional protocols was conducted to provide an evidence-based foundation for elective surgery.

METHODS

The articles were searched in PubMed, EBSCO, MEDLINE, Science Direct, Cochrane Library, CNKI, China Biomedical Resources Database, Wanfang Database, Weipu, and Western Biomedical Journal Literature Database. RCTs related to fasting before surgery during the screening period were selected. Chinese and English search keywords included elective surgery, preoperative, fasting and no drinking, patient comfort, thirst, hunger, collapse, hypoglycemia, preoperative gastric volume, preoperative gastric juice pH, and intraoperative gastric volume. The RevMan 5.3 software provided by Cochrane collaboration network was used to evaluate the quality of included documents. Two professionals independently screened the literature, extracted data, and assessed the risk of bias.

RESULTS

A total of 6 studies were included. The incidence of hunger in patients undergoing elective surgery in the experimental group and control group was significantly different [Z=3.90; relative risk (RR) =0.58; 95% confidence interval (CI): 0.44, 0.76; P<0.0001]. The incidence of thirst was significantly different between the experimental group and control group (Z=7.22; RR =0.21; 95% CI: 0.13, 0.32; P<0.00001).

DISCUSSION

Meta-analysis results confirmed that the new guidelines can significantly reduce the hunger and thirst of patients, improve their satisfaction after surgery, and can be applied clinically.

Preoperative carbohydrate loading before elective abdominal surgery: A systematic review and network meta-analysis of phase II/III randomized controlled trials

BACKGROUND & AIMS

The preoperative use of carbohydrate loading (CHO) is recommended in patients undergoing abdominal surgery, even if the advantages remain debatable. The aim was to evaluate the CHO benefits in patients undergoing abdominal surgery.

METHODS

A systematic search of randomized clinical trials was made. A frequentist random-effects network meta-analysis was carried out, reporting the surface under the cumulative ranking (SUCRA). The primary endpoint regarded the morbidity rate. The secondary endpoints were aspiration/regurgitation rates, the length of stay (LOS), the rate of postoperative nausea and vomiting (PONV), the changes (Δ) in insulin sensitivity or resistance, and the postoperative C- reactive protein (CRP) values.

RESULTS

CHO loading and water administration had a similar probability of being the approach with a lower morbidity rate (SUCRA = 62.4% and 64.7%). CHO and clear water also had a similar chance of avoiding the PONV (SUCRA of 80.8% and 77%). The aspiration regurgitation rate was not relevant in non-fasting patients (0.06%). CHO administration was associated with the shorter hospitalization (SUCRA 86.9%), with the best metabolic profile (SUCRA values for insulin resistance and sensitivity were 81.1% and 76%). CHO enriched was the best approach for postoperative CRP values. Preoperative fasting was the worst approach for morbidity, PONV, insulin resistance and sensitivity, and CRP (SUCRA values of 32.1%, 21.7%, 10.2%, 3.2%, and 2.0%).

CONCLUSION

Both preoperative CHO loading and clear water use were superior to the fasting about morbidity. CHO drinks use could provide specific advantages, reduce the PONV rate, and improve carbohydrate homeostasis, inflammatory pathway, and hospitalization.

The impact of oral carbohydrate-rich supplement taken two hours before caesarean delivery on maternal and neonatal perioperative outcomes -- a randomized clinical trial

Background

To evaluate the impact of oral carbohydrate-rich (Ch-R) supplement taken 2 hours before an elective caesarean delivery (CD) on maternal and neonatal perioperative outcomes.

Methods

Ninety pregnant women undergoing elective CD were randomized into the Ch-R group, placebo group and fasting group equally. Participants’ blood was drawn at three time points, before intervention, immediately after and 1 day after the surgery to measure maternal and neonatal biochemical indices. Meanwhile women’s perioperative symptoms and signs were recorded.

Results

Eighty-eight pregnant women were finally included in the study. Women who had drunk Ch-R supplement had lower postoperative insulin level (β = − 3.50, 95% CI − 5.45 to − 1.56), as well as postoperative HOMA-IR index (β = − 0.74, 95% CI − 1.15 to − 0.34), compared with women who had fasted. Additionally, neonates of mothers who were allocated in the Ch-R group also had a higher glucose level, compared with neonates of mothers in the fasting group (β = 0.40, CI 0.17 to 0.62).

Conclusion

Oral Ch-R solution administered 2 hours before an elective CD may not only alleviate maternal postoperative insulin resistance, but also comfort women’s preoperative thirst and hunger, compared to fasting. Additionally, it may increase neonatal glucose level as well.

Trial registration

Chinese Clinical Trial Registry, ChiCTR2000033163.

Data of Registration: 2020-5-22.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-021-04155-z.

Fasting habits over a 10-year period: An observational study on adherence to preoperative fasting and postoperative restoration of oral intake in 2 Dutch hospitals

BACKGROUND

Since 1999, international guidelines recommend fasting from solid foods up to 6 hours and clear liquids up to 2 hours before surgery. Early recovery after surgery programs recommend restoration of oral intake as soon as possible. This study determines adherence to these guidelines up to 20 years after its introduction.

METHODS

A 2-center observational study with a 10-year interval was performed in the Netherlands. In period 1 (2009), preoperative fasting time was observed as primary outcome. In period 2 (2019), preoperative fasting and postoperative restoration of oral intake were observed. Fasting times were collected using an interview-assisted questionnaire.

RESULTS

During both periods, 311 patients were included from vascular, trauma, orthopedic, urological, oncological, gastrointestinal, and ear-nose-throat and maxillary surgical units. Duration of preoperative fasting was prolonged in 290 (90.3%) patients for solid foods and in 208 (67.8%) patients for clear liquids. Median duration of preoperative fasting from solid foods and clear liquids was respectively 2.5 and 3 times the recommended 6 and 2 hours, with no improvements from one period to another. Postoperative food intake was resumed within 4 hours in 30.7% of the patients. Median duration of perioperative fasting was 23:46 hours (interquartile range 20:00-30:30 hours) for solid foods and 11:00 hours (interquartile range 7:53-16:00 hours) for clear liquids.

CONCLUSION

Old habits die hard. Despite 20 years of fasting guidelines, surgical patients are still exposed erroneously to prolonged fasting in 2 hospitals. Patients should be encouraged to eat and drink until 6 and 2 hours, respectively, before surgery and to restart eating after surgery.

Concept analysis of Perioperative Thirst for the development of a new nursing diagnosis

OBJECTIVES

to analyze the perioperative thirst concept for the development of a new diagnostic structure according to NANDA International.

METHODS

a concept analysis study based on the framework proposed by Walker and Avant, instrumentalized through an integrative literature review based on SCOPUS, CINAHL, PUBMED, LILACS, and WOS. The elaboration of the diagnostic structure followed NANDA International guidelines.

RESULTS

41 studies were analyzed revealing that perioperative thirst is prevalent and intense, having visceral and behavioral attributes as the core of the concept. Antecedents indicate that surgical patients are vulnerable to thirst; and consequents 16 signs and symptoms were organized and model cases were developed. A diagnostic structure has been developed for perioperative thirst.

FINAL CONSIDERATIONS

concept analysis allowed language standardization that describes thirsty patients, helping the identification, planning of actions and communication of perioperative nursing care.

Effects of preoperative oral carbohydrate on postoperative discomfort in patients undergoing elective surgery: a meta-analysis of randomized controlled trials

PURPOSE

Fasting is a standard preoperative procedure performed to prevent vomiting and pulmonary aspiration during anaesthesia and surgery. However, fasting can cause postoperative physical and psychological discomfort. Intake of oral carbohydrate (CHO) may mimic the intake of food, which prevents postoperative discomfort. We conducted a meta-analysis to evaluate the effect and safety of preoperative oral CHO in adult surgical patients.

METHODS

Randomized controlled trials (RCTs) were searched for in the PubMed, EMBASE, and Cochrane Library databases. A meta-analysis was performed to calculate a pooled effect size by using random-effects models. The satisfaction outcomes were mouth dryness, hunger, thirst, pain severity, duration of hospitalization, homeostatic model assessment for insulin resistance (HOMA-IR), and the incidence of postoperative nausea and vomiting. The safety outcomes were the incidence of aspiration and infection.

RESULTS

In total, 57 RCTs involving 5606 patients were included. The outcomes of mouth dryness, thirst, hunger, and pain were assessed by a 10-point visual analogue scale (0 = best, 10 = worst). The severity of mouth dryness (weighted mean difference [WMD]: -1.26, 95% CI: -2.36 to -0.15), thirst (WMD: -1.36, 95% CI: -2.05 to -0.67), hunger (WMD: -1.66, 95% CI: -2.53 to -0.80), pain (WMD: -0.68, 95% CI: -1.01 to -0.35), duration of hospitalization (WMD: -0.39 day, 95% CI: -0.66 to -0.12), and HOMA-IR (WMD: -1.80, 95% CI: -2.84 to -0.76) were significantly lower in the CHO group than in the control group. The incidence of postoperative nausea and vomiting did not differ between the CHO and control groups. No aspiration was recorded in any of the groups.

CONCLUSIONS

Preoperative CHO can alleviate patient's discomfort without safety concerns. Surgeons and anaesthesiologists should strongly promote preoperative CHO as a strategy to enhance recovery after surgery protocols.

Effects of a short message service (SMS) by cellular phone to improve compliance with fasting guidelines in patients undergoing elective surgery: a retrospective observational study

Background

Contemporary perioperative fasting guidelines aim to alleviate patient discomfort before surgery and enhance postoperative recovery whilst seeking to reduce the risk of pulmonary aspiration during anesthesia. The impact of a short message service (SMS) reminder on fasting guideline compliance is unknown. Therefore, we performed a retrospective observational study and quality improvement project aiming to quantify the extent of excessive and prolonged fasting, and then assessed the impact of a SMS reminder in reducing fasting times.

Methods

After ethics committee approval we performed a retrospective observational study investigating preoperative fasting times of adult patients undergoing elective surgery. First, we assessed whether the fasting guideline times were adhered to (Standard Care group). All patients received internationally recommended fasting guidelines in the form of a written hospital policy document. We then implemented an additional prompt via a mobile phone SMS 1 day prior to surgery containing a reminder of fasting guideline times (SMS group). The primary aims were to compare fasting times between the Standard Care group and the SMS group.

Results

The fasting times of 160 patients in the Standard Care group and 110 patients in the SMS group were evaluated. Adherence to the fasting guidelines for solids occurred in 14 patients (8.8%) in the Standard Care group vs. Twenty-two patients (13.6%) in the SMS group (p=0.01). Adherence to the fasting guidelines for fluids occurred in 4 patients (2.5%) in the Standard Care group vs. Ten patients (6.3%) in the SMS group (p=0.023). Patients in the Standard Care group had a longer median (inter-quartile range (IQR)) fasting time for fluids compared the SMS group [6.5 h (IQR 4.5:11) vs 3.5 h (IQR 3:8.5), p< 0.0001]. Median fasting times for solids were 11 h (IQR 7:14) in the Standard Care group and 11.5 h (IQR 7:13.5) in the SMS group (p=0.756).

Conclusion

Adherence to internationally recommended fasting guidelines for patients undergoing elective surgery is poor. The introduction of a fasting guideline reminder via a mobile phone SMS in addition to a written hospital policy improved adherence to fasting advice and reduced the fasting times for fluids but not for solids. The use of an SMS reminder of fasting guidelines is a simple, feasible, low-cost, and effective tool in minimising excessive fasting for fluids among elective surgical patients.

Trial registration

ACTRN12619001232123 (Australia New Zealand Clinical Trials Registry). Registered 6th September 2019 (retrospectively registered).

Safety and feasibility of oral carbohydrate consumption before cesarean delivery on patients with gestational diabetes mellitus: A parallel, randomized controlled trial

AIM

To investigate the safety and feasibility of taking low-concentration carbohydrate solution at 2 h before induction of anesthesia for gestational diabetes mellitus (GDM) patients.

METHODS

GDM patients undergoing cesarean section were randomly assigned to experimental group (n = 43) and control group (n = 42). Two hours before induction of anesthesia, participants in experimental group orally received 300 mL low-concentration carbohydrate solution, while those in control group received equivalent warm water. Blood glucose and serum insulin were measured at 2 h before induction of anesthesia, right before induction of anesthesia, and the morning of postoperative day 1. Neonatal blood glucose level was monitored at birth. Maternal gastrointestinal function and well-being were assessed perioperatively.

RESULTS

The levels of blood glucose and serum insulin right before induction of anesthesia in the experimental group were significantly higher than those in the control group. There were four cases with hypoglycemia in the experimental group and 19 cases in the control group right before induction of anesthesia (9.3% vs 45.2%, p < 0.001). The incidence of neonatal hypoglycemia was 2.3% in the experimental group and 7.1% in the control group with no significance. Hunger score of the participants between the two groups right before induction of anesthesia was significantly different. No aspiration, nausea, and vomiting occurred in both groups before, during, and after surgery. No significant difference was found in the time to the first flatus and abdominal distension between the two groups.

CONCLUSION

Taking low-concentration carbohydrate solution is safe and feasible for patients with GDM undergoing elective cesarean section.

Comparison of perioperative patient comfort with 'enhanced recovery after surgery (ERAS) approach' versus 'traditional approach' for elective laparoscopic cholecystectomy

Background:

Perioperative anxiety, hunger, thirst, fatigue, pain along with nausea and vomiting can influence a patient's recovery after surgery. We aimed to compare 'enhanced recovery after surgery' (ERAS) protocol with a traditional perioperative approach to evaluate a patient's recovery after elective laparoscopic cholecystectomy.

Methods:

A prospective randomised controlled study was conducted after institutional ethical clearance on 50 patients undergoing elective laparoscopic cholecystectomy, and divided equally into two groups. In group 1 (traditional); standard fasting guidelines and routine perioperative management was implemented. In group 2 (ERAS); patients received appropriate multimedia information about surgery and anaesthesia besidecarbohydrate loading with tender coconut water on the previous night and on the morning of surgery. Standard guidelines of fasting for solids were followed. Intraoperatively, goal-directed fluid therapy and an inspired oxygen concentration of 60% were administered. Postoperatively, early diet and mobilisation were initiated. The primary outcome was the assessment of perioperative anxiety. Hunger, thirst, fatigue, pain, nausea, vomiting and overall perioperative experience were also evaluated.

Results:

ERAS group had reduced anxiety prior to surgery: median (interquartile range) 3 (3–4) vs 2 (2–3) (P = 0.003), and at 6 h postoperatively: 4 (3–6) vs 3 (1–4) (P = 0.001). Hunger, thirst and fatigue (P < 0.01) were also decreased with better overall perioperative experience (5 [4–5] vs 6 [5–7], P = 0.004). Pain, nausea, vomiting and blood glucose were similar between the groups.

Conclusion:

'ERAS approach reduces anxiety in addition to hunger, thirst and fatigue with enhanced overall perioperative comfort in patients undergoing laparoscopic cholecystectomy.

Impact of oral carbohydrate consumption prior to cesarean delivery on preoperative well-being: a randomized interventional study

PURPOSE

Oral carbohydrate consumption before surgery improves insulin sensitivity, cardiac output and well-being, and shortens hospital stays without adverse effects. No work has compared higher-dose carbohydrate beverages made for preoperative consumption to common, commercial oral rehydration solutions with lower carbohydrate concentrations.

METHODS

We recruited low-risk women undergoing scheduled cesarean deliveries with planned spinal anesthesia. Participants were randomized to one of three groups: those who consumed Clearfast^® beverage, those who consumed Gatorade Thirst Quencher^® beverage, or fasting control. Participants in the two beverage groups received 710 mL of the appropriate beverage the night before surgery and 355 mL 2 h before surgery. Participants in the control group fasted after midnight the night before surgery. Two hours before surgery, we recorded baseline patient well-being using visual analogue scales, followed by beverage consumption for subjects in the beverage groups. One hour later, we repeated the same assessment. Additional recorded measures included cord blood glucose level, intraoperative variables, breastfeeding success, and a quality of recovery assessment administered 1 day after surgery.

RESULTS

Forty-seven patients were recruited: 15 received Clearfast^®, 17 received Gatorade Thirst Quencher^®, and 15 patients fasted after midnight. Group differences in change in patient well-being using visual analog scales were analyzed using linear regression. Both beverage-consuming groups showed significant improvements in patient well-being using visual analog scales while fasted patients showed no change.

CONCLUSION

Either a common oral rehydration beverage or a higher-dose carbohydrate beverage consumed preoperatively resulted in superior well-being compared to fasting. No differences in other outcomes were noted.

TRIAL REGISTRATION

This study was registered on ClinicalTrials.gov with clinical trial registration number: NCT02684513.

Are carbohydrate drinks more effective than preoperative fasting: A systematic review of randomised controlled trials

AIMS AND OBJECTIVES

To evaluate current evidence to determine whether oral preoperative carbohydrate drinks shorten hospital stays, reduce insulin resistance and/or improve postoperative discomfort for patients undergoing abdominal or cardiac surgery.

BACKGROUND

Criticisms of standard preoperative fasting have forced practitioners to explore new ways of preparing patients for theatre. Consequently, the use of preoperative carbohydrate drinks prior to elective surgery has gained momentum. Current evidence regarding the efficacy of this treatment has been inconsistent and contradictory which prompted a review of the current literature.

DESIGN

A systematic review of randomised clinical trials (RCTs).

METHODS

In accordance with Prisma guidelines, the review incorporated a systematic, comprehensive search of English-language-only texts published between 2001-2018. The search focused on five databases (MEDLINE, EMBASE, CINAHL, British Nursing Index and ASSIA). Reference lists of relevant systematic reviews and studies located were also hand-searched for eligibility and further references. All RCTs investigating the effect of preoperative carbohydrate drinks on adult patients undergoing cardiac or abdominal surgery were included. The review excluded RCTs conducted on patients with type 1 or 2 diabetes mellitus and patients under the age of 18.

RESULT

The review included 22 RCTs with a total sample of 2,065 patients across thirteen countries. Nine different types of surgery were identified. No significant reductions in hospital stay were noted in 8 of the ten trials. Preoperative carbohydrate drinks significantly reduced insulin resistance and improved postoperative discomfort especially in patients undergoing laparoscopic cholecystectomy. No definite conclusion regarding the impact of preoperative carbohydrate drinks on gastric volume and gastric pH was noted. Similarly, no adverse events such as pulmonary aspiration were reported.

CONCLUSION

Preoperative carbohydrate drinks were found to be safe and can be administered up to 2 hr before surgery. Such drinks were also found to reduce insulin resistance and improve postoperative discomfort especially in patients undergoing laparoscopic cholecystectomy. However, there is insufficient evidence to definitively conclude what impact they have on length of hospital stay.

RELEVANCE TO CLINICAL PRACTICE

Patients undergoing surgery are often required to fast from midnight, while in some extreme cases patients are fasted for up to 24 hr prior to surgery. The main purpose of asking patients to undergo this prolonged fasting is to reduce the risk of aspiration. However, there is a general consensus that this traditional practice is out of date, and it is often associated with postoperative complications. On the other hand, current evidence suggests oral intake of fluids up to 90-180 min prior to surgery is safe and consumption of a preoperative carbohydrate drinks does not delay gastric emptying or affect gastric acidity.

Effects of Preoperative Oral Carbohydrates on Quality of Recovery in Laparoscopic Cholecystectomy: A Randomized, Double Blind, Placebo-Controlled Trial

BACKGROUND

While carbohydrate loading is an important component of enhanced patient recovery after surgery, no study has evaluated the effects of preoperative carbohydrate loading after laparoscopic cholecystectomy (LC) on patient satisfaction and overall recovery. Thus, we aimed to investigate the impact of preoperative oral carbohydrates on scores from the quality of recovery 40-item (QoR-40) questionnaire after LC.

METHODS

A total of 153 adults who underwent LC were randomized into three groups. Group MN-NPO was fasted from midnight until surgery. Group No-NPO received 400 mL of a carbohydrate beverage on the evening before surgery, and a morning dose of 400 mL was ingested at least 2 h before surgery. Group Placebo received the same quantity of flavored water as for group No-NPO. The quality of recovery after general anesthesia was evaluated using QoR-40 questionnaire. Intraoperative hemodynamics were also evaluated.

RESULTS

There were no significant differences among the groups in terms of the pre- and postoperative global QoR-40 scores (P = 0.257). Group MN-NPO had an elevated heart rate compared to patients who ingested a preoperative beverage (groups No-NPO and Placebo; P = 0.0412).

CONCLUSIONS

The preoperative carbohydrate beverage did not improve quality of recovery using the QoR-40 questionnaire after general anesthesia for laparoscopic cholecystectomy compared to placebo or conventional fasting. However, the preoperative fasting group had a consistently increased heart rate during changes in body position that induced hypotension, which is likely a result of depletion of effective intravascular volume caused by traditional fasting over 8 h.

TRIAL REGISTRATION

Clinical trial.gov identifier: NCT02555020.

Impact of Nutrition on Enhanced Recovery After Surgery (ERAS) in Gynecologic Oncology

Enhanced recovery after surgery (ERAS) pathways aim to improve surgical outcomes by applying evidence-based practices before, during, and after surgery. Patients undergoing surgery for gynecologic malignancies are at high risk of complications due to population, patient, disease, and surgical factors. The nutritional status of the patient provides the foundation for recovery after surgery, and opportunities to optimize outcomes exist from the first patient assessment to the early days after surgery. This review highlights the importance of nutritional assessment and intervention during the pre-operative and post-operative periods in the context of ERAS in gynecologic oncology surgery. The emerging role of immunonutrition, carbohydrate loading, and the importance of individualized care are explored. Evidence from studies in gynecologic oncology is presented, where available, and extrapolated from colorectal and other cancer surgery trials when applicable.

Perioperative Fluid Management in the Enhanced Recovery after Surgery (ERAS) Pathway

Fluid management is an essential component of the Enhanced Recovery after Surgery (ERAS) pathway. Optimal management begins in the preoperative period and continues through the intraoperative and postoperative phases. In this review, we outline current evidence-based practices for fluid management through each phase of the perioperative period. Preoperatively, patients should be encouraged to hydrate until 2 hours prior to the induction of anesthesia with a carbohydrate-containing clear liquid. When mechanical bowel preparation is necessary, with modern isoosmotic solutions, fluid repletion is not necessary. Intraoperatively, fluid therapy should aim to maintain euvolemia with an individualized approach. While some patients may benefit from goal-directed fluid therapy, a restrictive, zero-balance approach to intraoperative fluid management may be reasonable. Postoperatively, early initiation of oral intake and cessation of intravenous therapy are recommended.

Ultrasound dynamics of gastric content volumes after the ingestion of coconut water or a meat sandwich. A randomized controlled crossover study in healthy volunteers

Background

Adequate preoperative fasting is critical in preventing pulmonary aspiration of gastric content. We proposed to study the sonographic gastric content dynamics after the ingestion of liquid or solid food in healthy volunteers and confront it with current guidelines for preoperative fasting times.

Methods

We performed a prospective, crossover, evaluator-blinded study involving 17 healthy volunteers of both sexes. Each participant fasted for 10 h and was subjected to a baseline gastric ultrasound, intake of 400 mL of coconut water or a 145 g, 355 kcal meat sandwich, and sonographic gastric evaluations after 10 min and every hour until the stomach was completely empty.

Results

At baseline, all subjects had an empty stomach. At 10 min, gastric content [mean + standard deviation (SD)] was 240.4 + 69.3 and 248.2 + 119.2 mL for liquid and solid foods, respectively (p > 0.05). Mean + SD gastric emptying times were 2.5 + 0.7 and 4.5 + 0.9 h for liquid and solid foods, respectively (p < 0.001). For the drink, the stomach was completely empty in 59% and 100% of the subjects after two and four hours, and for the sandwich, 65% and 100% of the subjects after four and seven hours, respectively.

Conclusions

Sonographic gastric dynamics for coconut water and a meat sandwich resulted in complete gastric emptying times higher and lower, respectively, than those suggested by current guidelines for preoperative fasting.

[Ultrasound dynamics of gastric content volumes after the ingestion of coconut water or a meat sandwich. A randomized controlled crossover study in healthy volunteers]

BACKGROUND

Adequate preoperative fasting is critical in preventing pulmonary aspiration of gastric content. We proposed to study the sonographic gastric content dynamics after the ingestion of liquid or solid food in healthy volunteers and confront it with current guidelines for preoperative fasting times.

METHODS

We performed a prospective, crossover, evaluator-blinded study involving 17 healthy volunteers of both sexes. Each participant fasted for 10h and was subjected to a baseline gastric ultrasound, intake of 400mL of coconut water or a 145g, 355kcal meat sandwich, and sonographic gastric evaluations after 10min and every hour until the stomach was completely empty.

RESULTS

At baseline, all subjects had an empty stomach. At 10min, gastric content [mean + standard deviation (SD)] was 240.4 + 69.3 and 248.2 + 119.2mL for liquid and solid foods, respectively (p>0.05). Mean + SD gastric emptying times were 2.5 + 0.7 and 4.5 + 0.9h for liquid and solid foods, respectively (p<0.001). For the drink, the stomach was completely empty in 59% and 100% of the subjects after two and four hours, and for the sandwich, 65% and 100% of the subjects after four and seven hours, respectively.

CONCLUSIONS

Sonographic gastric dynamics for coconut water and a meat sandwich resulted in complete gastric emptying times higher and lower, respectively, than those suggested by current guidelines for preoperative fasting.

Influence of Fasting Duration on Body Fluid and Hemodynamics

Fasting before general anesthesia aims to reduce the volume and acidity of stomach contents, which reduces the risk of regurgitation and aspiration. Prolonged fasting for many hours prior to surgery could lead to unstable hemodynamics, however. Therefore, preoperative oral intake of clear fluids 2 hours prior to surgery is recommended to decrease dehydration without an increase in aspiration risk. In this study, we investigated the body fluid composition and hemodynamics of patients undergoing general anesthesia as the first case of the day versus the second subsequent case. We retrospectively reviewed the general anesthesia records of patients over 20 years old who underwent oral maxillofacial surgery. We investigated patient demographics, preoperative fasting time, anesthetic time, urine output, infusion volume, and opioid and vasopressor use. With respect to body fluid and hemodynamics, we extracted the data from the induction of anesthesia through 2 hours of anesthesia time. Thirty patients were suitable for this study. Patients were divided into 2 groups: patients who underwent surgery as the first case of the day (am group: n = 15) and patients who underwent surgery as the second case (pm group: n = 15). There were no significant differences between the 2 groups in patient demographics. In the pm group, fasting time for a light meal (832 minutes) was significantly longer than for the am group (685 minutes), p = .005. In the pm group, fasting time for clear fluids (216 minutes) was also significantly longer than for the am group (194 minutes), p = .005. Body fluid composition was not significantly different between the 2 groups. In addition, cardiac parameters intraoperatively were stable. In the pm group, vasopressors were used in 4 patients at the induction of anesthesia (p = .01). There were not statistically significant changes in cardiac function or body fluid composition between patients treated as the first case of the day vs patients who underwent surgery with general anesthesia as the second case of the day.

The effect of preparative solid food status on the occurrence of nausea, vomiting and aspiration symptoms in enhanced CT examination: prospective observational study

OBJECTIVE:

To evaluate the correlation between preparative solid food status and the incidence of nausea, vomiting and aspiration symptoms in contrast-enhanced CT examination, and to provide direction for standardizing the preparative dietary policies.

METHODS:

Patients who underwent routine enhanced CT examination at our hospital between June 2015 and June 2017 (110,836 cases) were enrolled and allocated into solid food fasting group (51,807 cases) and solid food non-fasting group (59,029 cases). Fluids ingestion was not restricted for any case. The differences in the incidence of nausea, vomiting and aspiration symptoms between the two groups of patients with various basic data were compared. The risk factors for the occurrence of nausea, vomiting and aspiration symptoms were analyzed.

RESULTS:

The total incidence of nausea and vomiting was extremely low (0.071%), and no aspiration developed. There was no significant difference in the incidence of nausea and vomiting between the two groups in all respects (p > 0.05). The incidence of nausea and vomiting in patients with an iodine adverse drug reaction (ADR) history was higher than those with other ADR history (p = 0.008) and those without ADR history (p = 0.001).

CONCLUSION:

The occurrence of nausea and vomiting has no correlation with the preparative solid food status. Unless compulsory in clinical needs and constraints and gastrointestinal examination, solid food fasting is not a must in other examinations. Particular attention should be paid to the patients with an iodine ADR history in an effort to prevent possible ADRs.

ADVANCES IN KNOWLEDGE:

The correlation between preparative solid food status and the incidence of nausea, vomiting and aspiration symptoms in contrast-enhanced CT examination were comprehensively analyzed in a large-scale population.

ACERTO guidelines of perioperative nutritional interventions in elective general surgery

ABSTRACT Objective: to present recommendations based on the ACERTO Project (Acceleration of Total Post-Operative Recovery) and supported by evidence related to perioperative nutritional care in General Surgery elective procedures. Methods: review of relevant literature from 2006 to 2016, based on a search conducted in the main databases, with the purpose of answering guiding questions previously formulated by specialists, within each theme of this guideline. We preferably used randomized controlled trials, systematic reviews and meta-analyzes but also selected some cohort studies. We contextualized each recommendation-guiding question to determine the quality of the evidence and the strength of this recommendation (GRADE). This material was sent to authors using an open online questionnaire. After receiving the answers, we formalized the consensus for each recommendation of this guideline. Results: the level of evidence and the degree of recommendation for each item is presented in text form, followed by a summary of the evidence found. Conclusion: this guideline reflects the recommendations of the group of specialists of the Brazilian College of Surgeons, the Brazilian Society of Parenteral and Enteral Nutrition and the ACERTO Project for nutritional interventions in the perioperative period of Elective General Surgery. The prescription of these recommendations can accelerate the postoperative recovery of patients submitted to elective general surgery, with decrease in morbidity, length of stay and rehospitalization, and consequently, of costs.

Enhanced recovery after surgery-Preoperative fasting and glucose loading-A review

In this review, we explore the rationale and history behind the practice of preoperative fasting in elective surgery including the gradual move toward longer fasting and the more recent change in direction of practice. Gastric emptying physiology and the metabolic effects of prolonged fasting and carbohydrate loading are examined. Most recent guidelines related to these topics are discussed and practical recommendations for implementing these guidelines are suggested.

Practice Guidelines for Preoperative Fasting and the Use of Pharmacologic Agents to Reduce the Risk of Pulmonary Aspiration: Application to Healthy Patients Undergoing Elective Procedures

Supplemental Digital Content is available in the text.

Shortened preoperative fasting for prevention of complications associated with laparoscopic cholecystectomy: a meta-analysis

Objective Routine fasting (12 h) is always applied before laparoscopic cholecystectomy, but prolonged preoperative fasting causes thirst, hunger, and irritability as well as dehydration, low blood glucose, insulin resistance and other adverse reactions. We assessed the safety and efficacy of a shortened preoperative fasting period in patients undergoing laparoscopic cholecystectomy. Methods We searched PubMed, Embase and Cochrane Central Register of Controlled Trials up to 20 November 2015 and selected controlled trials with a shortened fasting time before laparoscopic cholecystectomy. We assessed the results by performing a meta-analysis using a variety of outcome measures and investigated the heterogeneity by subgroup analysis. Results Eleven trials were included. Forest plots showed that a shortened fasting time reduced the operative risk and patient discomfort. A shortened fasting time also reduced postoperative nausea and vomiting as well as operative vomiting. With respect to glucose metabolism, a shortened fasting time significantly reduced abnormalities in the ratio of insulin sensitivity. The C-reactive protein concentration was also reduced by a shortened fasting time. Conclusions A shortened preoperative fasting time increases patients' postoperative comfort, improves insulin resistance, and reduces stress responses. This evidence supports the clinical application of a shortened fasting time before laparoscopic cholecystectomy.

Network meta-analysis of the effect of preoperative carbohydrate loading on recovery after elective surgery

BACKGROUND

Three meta-analyses have summarized the effects of preoperative carbohydrate administration on postoperative outcomes in adult patients undergoing elective surgery. However, these studies could not account for the different doses of carbohydrate administered and the different controls used. Multiple-treatments meta-analysis allows robust synthesis of all available evidence in these situations.

METHODS

Article databases were searched systematically for RCTs comparing preoperative carbohydrate administration with water, a placebo drink, or fasting. A four-treatment multiple-treatments meta-analysis was performed comparing two carbohydrate dose groups (low, 10-44 g; high, 45 g or more) with two control groups (fasting; water or placebo). Primary outcomes were length of hospital stay and postoperative complication rate. Secondary outcomes included postoperative insulin resistance, vomiting and fatigue.

RESULTS

Some 43 trials involving 3110 participants were included. Compared with fasting, preoperative low-dose and high-dose carbohydrate administration decreased postoperative length of stay by 0·4 (95 per cent c.i. 0·03 to 0·7) and 0·2 (0·04 to 0·4) days respectively. There was no significant decrease in length of stay compared with water or placebo. There was no statistically significant difference in the postoperative complication rate, or in most of the secondary outcomes, between carbohydrate and control groups.

CONCLUSION

Carbohydrate loading before elective surgery conferred a small reduction in length of postoperative hospital stay compared with fasting, and no benefit in comparison with water or placebo.

Preoperative carbohydrate treatment for enhancing recovery after elective surgery

BACKGROUND

Preoperative carbohydrate treatments have been widely adopted as part of enhanced recovery after surgery (ERAS) or fast-track surgery protocols. Although fast-track surgery protocols have been widely investigated and have been shown to be associated with improved postoperative outcomes, some individual constituents of these protocols, including preoperative carbohydrate treatment, have not been subject to such robust analysis.

OBJECTIVES

To assess the effects of preoperative carbohydrate treatment, compared with placebo or preoperative fasting, on postoperative recovery and insulin resistance in adult patients undergoing elective surgery.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (2014, Issue 3), MEDLINE (January 1946 to March 2014), EMBASE (January 1947 to March 2014), the Cumulative Index to Nursing and Allied Health Literature (CINAHL) (January 1980 to March 2014) and Web of Science (January 1900 to March 2014) databases. We did not apply language restrictions in the literature search. We searched reference lists of relevant articles and contacted known authors in the field to identify unpublished data.

SELECTION CRITERIA

We included all randomized controlled trials of preoperative carbohydrate treatment compared with placebo or traditional preoperative fasting in adult study participants undergoing elective surgery. Treatment groups needed to receive at least 45 g of carbohydrates within four hours before surgery or anaesthesia start time.

DATA COLLECTION AND ANALYSIS

Data were abstracted independently by at least two review authors, with discrepancies resolved by consensus. Data were abstracted and documented pro forma and were entered into RevMan 5.2 for analysis. Quality assessment was performed independently by two review authors according to the standard methodological procedures expected by The Cochrane Collaboration. When available data were insufficient for quality assessment or data analysis, trial authors were contacted to request needed information. We collected trial data on complication rates and aspiration pneumonitis.

MAIN RESULTS

We included 27 trials involving 1976 participants Trials were conducted in Europe, China, Brazil, Canada and New Zealand and involved patients undergoing elective abdominal surgery (18), orthopaedic surgery (4), cardiac surgery (4) and thyroidectomy (1). Twelve studies were limited to participants with an American Society of Anaesthesiologists grade of I-II or I-III.A total of 17 trials contained at least one domain judged to be at high risk of bias, and only two studies were judged to be at low risk of bias across all domains. Of greatest concern was the risk of bias associated with inadequate blinding, as most of the outcomes assessed by this review were subjective. Only six trials were judged to be at low risk of bias because of blinding.In 19 trials including 1351 participants, preoperative carbohydrate treatment was associated with shortened length of hospital stay compared with placebo or fasting (by 0.30 days; 95% confidence interval (CI) 0.56 to 0.04; very low-quality evidence). No significant effect on length of stay was noted when preoperative carbohydrate treatment was compared with placebo (14 trials including 867 participants; mean difference -0.13 days; 95% CI -0.38 to 0.12). Based on two trials including 86 participants, preoperative carbohydrate treatment was also associated with shortened time to passage of flatus when compared with placebo or fasting (by 0.39 days; 95% CI 0.70 to 0.07), as well as increased postoperative peripheral insulin sensitivity (three trials including 41 participants; mean increase in glucose infusion rate measured by hyperinsulinaemic euglycaemic clamp of 0.76 mg/kg/min; 95% CI 0.24 to 1.29; high-quality evidence).As reported by 14 trials involving 913 participants, preoperative carbohydrate treatment was not associated with an increase or a decrease in the risk of postoperative complications compared with placebo or fasting (risk ratio of complications 0.98, 95% CI 0.86 to 1.11; low-quality evidence). Aspiration pneumonitis was not reported in any patients, regardless of treatment group allocation.

AUTHORS' CONCLUSIONS

Preoperative carbohydrate treatment was associated with a small reduction in length of hospital stay when compared with placebo or fasting in adult patients undergoing elective surgery. It was found that preoperative carbohydrate treatment did not increase or decrease postoperative complication rates when compared with placebo or fasting. Lack of adequate blinding in many studies may have contributed to observed treatment effects for these subjective outcomes, which are subject to possible biases.