Effects of a New Metabolic Conditioning Supplement on Perioperative Metabolic Stress and Clinical Outcomes: A Randomized, Placebo-Controlled Trial

The effect of preoperative oral nutritional supplementation on surgical site infections among adult patients undergoing elective surgery: A systematic review and meta-analysis

INTRODUCTION

Mixed findings are reported on the effect of oral nutritional supplements in reducing Surgical Site Infections (SSIs).

MATERIAL AND METHODS

PubMED, EMBASE and Cochrane were searched. Studies from inception to July 2022 were included if they involved adults undergoing elective surgery and compared preoperative macronutrient oral nutritional supplements to placebo/standard diet.

RESULTS

Of 372 unique citations, 19 were included (N ​= ​2480): 13 RCTs (N ​= ​1506) and 6 observational studies (N ​= ​974). Moderate-certainty evidence suggested that nutritional supplements SSI risk (OR 0.54, 95% C.I. 0.40-0.72, N ​= ​2718 participants). In elective colorectal surgery, this risk-reduction was 0.43 (95% C.I. 0.26-0.61, N ​= ​835 participants) and among patients who received Impact 0.48 (95% C.I. 0.32-0.70, N ​= ​1338).

CONCLUSION

Oral nutritional supplements prior to adult elective surgery may significantly reduce SSIs, with an overall 50% protective effect. This protective effect persisted in subgroup analysis of colorectal surgery patients and the use of Impact.

Pre-admission interventions (prehabilitation) to improve outcome after major elective surgery: a systematic review and meta-analysis

OBJECTIVE

To determine the benefits and harms of pre-admission interventions (prehabilitation) on postoperative outcomes in patients undergoing major elective surgery.

DESIGN

Systematic review and meta-analysis of randomised controlled trials (RCTs) (published or unpublished). We searched Medline, Embase, CENTRAL, DARE, HTA and NHS EED, The Cochrane Library, CINAHL, PsychINFO and ISI Web of Science (June 2020).

SETTING

Secondary care.

PARTICIPANTS

Patients (≥18 years) undergoing major elective surgery (curative or palliative).

INTERVENTIONS

Any intervention administered in the preoperative period with the aim of improving postoperative outcomes.

OUTCOMES AND MEASURES

Primary outcomes were 30-day mortality, hospital length of stay (LoS) and postoperative complications. Secondary outcomes included LoS in intensive care unit or high dependency unit, perioperative morbidity, hospital readmission, postoperative pain, heath-related quality of life, outcomes specific to the intervention, intervention-specific adverse events and resource use.

REVIEW METHODS

Two authors independently extracted data from eligible RCTs and assessed risk of bias and the certainty of evidence using Grading of Recommendations, Assessment, Development and Evaluation. Random-effects meta-analyses were used to pool data across trials.

RESULTS

178 RCTs including eight types of intervention were included. Inspiratory muscle training (IMT), immunonutrition and multimodal interventions reduced hospital LoS (mean difference vs usual care: -1.81 days, 95% CI -2.31 to -1.31; -2.11 days, 95% CI -3.07 to -1.15; -1.67 days, 95% CI -2.31 to -1.03, respectively). Immunonutrition reduced infective complications (risk ratio (RR) 0.64 95% CI 0.40 to 1.01) and IMT, and exercise reduced postoperative pulmonary complications (RR 0.55, 95% CI 0.38 to 0.80, and RR 0.54, 95% CI 0.39 to 0.75, respectively). Smoking cessation interventions reduced wound infections (RR 0.28, 95% CI 0.12 to 0.64).

CONCLUSIONS

Some prehabilitation interventions may reduce postoperative LoS and complications but the quality of the evidence was low.

PROSPERO REGISTRATION NUMBER

CRD42015019191.

Effects of Selenium Supplementation on Metabolic Status in Patients Undergoing for Coronary Artery Bypass Grafting (CABG) Surgery: a Randomized, Double-Blind, Placebo-Controlled Trial

This study was carried out to evaluate the effects of selenium supplementation on glycemic control, lipid profiles, and biomarkers of inflammation and oxidative stress in patients undergoing for coronary artery bypass grafting (CABG) surgery. This randomized, double-blind, placebo-controlled trial was performed among 33 patients undergoing for CABG surgery, aged 40-85 years old. Subjects were randomly allocated into two groups to intake either 200 μg/day selenium supplements as selenium yeast (n = 17) or placebo (n = 16) for 4 weeks. Glycemic control, lipid profiles, and biomarkers of inflammation and oxidative stress were assessed at baseline and at the end of trial. After the 4-week intervention, selenium supplementation significantly decreased fasting plasma glucose (FPG) (β, 6.76 mg/dL; 95% CI, - 13.13, - 0.40; P = 0.03), insulin (β, - 1.14 μIU/mL; 95% CI, - 2.01, - 0.28; P = 0.01); homeostasis model of assessment-estimated insulin resistance (HOMA-IR) (β - 0.35; 95% CI, - 0.62, - 0.08; P = 0.01); and total-/HDL-cholesterol ratio (β - 0.31; 95% CI, - 0.51, - 0.09; P = 0.008); and significantly increased HDL-cholesterol levels (β, 2.72 mg/dL; 95% CI, 0.89, 4.55; P = 0.005) compared with the placebo. Moreover, selenium supplementation led to a significant reduction in high-sensitivity C-reactive protein (hs-CRP) (β, - 0.68 mg/L; 95% CI, - 1.18, - 0.17; P = 0.01) and malondialdehyde (MDA) (β, - 0.27 μmol/L; 95% CI, - 0.47, - 0.07; P = 0.009), and a significant elevation in total glutathione (GSH) levels (β, 77.33 μmol/L; 95% CI, 56.11, 98.55; P < 0.001) compared with the placebo. Selenium supplementation did not affect other metabolic profiles. Overall, our study demonstrated that selenium supplementation for 4 weeks to patients undergoing for CABG surgery had beneficial effects on FPG, insulin, HOMA-IR, total-/HDL-cholesterol ratio, HDL-cholesterol, hs-CRP, GSH, and MDA levels, but did not affect other metabolic profiles. Clinical trial registration number: http://www.irct.ir : IRCT2017090533941N22.

A randomised controlled study of preoperative oral carbohydrate loading versus fasting in patients undergoing colorectal surgery

PURPOSE

This study aimed to evaluate the effect of preoperative carbohydrate oral (CHO) loading on the postoperative metabolic and inflammatory response, perioperative discomfort and surgical clinical outcomes in open colorectal surgery compared with a conventional fasting protocol.

METHODS

Fifty patients were randomly allocated to either the intervention group (CHO), to receive preoperative oral carbohydrate supplementation, or the control group (FAST), to undergo preoperative fasting. Insulin resistance, insulin sensitivity, the Glasgow Prognostic Score (GPS) and IL-6 levels were analysed at 06 h on the day of surgery (T₁), 6 h after surgery (T₂) and at 06 h on postoperative day 1 (T₃) and postoperative day 2 (T₄). Thirst, hunger, dry mouth, weakness, anxiety and pain were assessed using the visual analogue scale (VAS) prior to anaesthesia induction and at 0-4, 4-8, 8-12 and 12-24 h after surgery. Surgical clinical outcomes included the return of gastrointestinal function, time to independent ambulation and postoperative discharge day.

RESULTS

Postoperative insulin resistance was 30% lower (p < 0.03) and insulin sensitivity was 15% higher (p < 0.05) in the CHO group than in the FAST group. The GPS was lower in the CHO group at T₁ (p < 0.001), T₃ (p < 0.01) and T₄ (p < 0.004). IL-6 serum levels were lower at the analysed postoperative time points in the CHO group (p < 0.001). The VAS well-being score was lower in the intervention group (p < 0.001); however, the VAS pain score was not significantly different between the groups. The evaluated surgical outcomes appeared earlier in the CHO group (p < 0.001).

CONCLUSION

A preoperative CHO drink reduced the postoperative metabolic and inflammatory response and improved subjective well-being and surgical clinical outcomes but did not diminish the VAS pain score.

The effects of L-carnitine supplementation on glycemic control: a systematic review and meta-analysis of randomized controlled trials

The findings of trials investigating the effect of L-carnitine administration on glycemic control are controversial. This meta-analysis of randomized controlled trials (RCTs) was performed to explore the effects of L-carnitine intake on glycemic control. Two authors independently searched electronic databases including MEDLINE, EMBASE, Cochrane Library, Web of Science, PubMed and Google scholar from 1990 until February 2019, in order to find relevant RCTs. 37 studies with 44 effect sizes met the inclusion criteria and were eligible for the meta-analysis. L-carnitine supplementation resulted in a significant reduction in fasting plasma glucose (FPG) (WMD: -4.57; 95 % CI: -6.88, -2.25), insulin (WMD: -1.21; 95 % CI: -1.85, -0.57), homeostatic model assessment for insulin resistance (HOMA-IR) (WMD: -0.67; 95 % CI: -0.90, -0.44) and HbA1C concentrations (WMD: -0.30; 95 % CI: -0.47, -0.13). L-Carnitine supplementation significantly reduced FPG, insulin, HOMA-IR, and HbA1c levels.