Hypocaloric peripheral parenteral nutrition with lipid emulsion in postoperative gastrointestinal cancer patients

Peripheral parenteral nutrition in surgery - a systematic review and meta-analysis

BACKGROUND

Peripheral parenteral nutrition (PPN) refers to the delivery of artificial nutrition via a peripheral intravenous cannula. As a nutritional intervention it remains under-utilised in peri-operative care. This is despite purported advantages which includes avoiding the risks associated with central venous lines and preventing potential delays to the initiation of nutrition support. This systematic review and meta-analysis will detail the available evidence for PPN use in surgery.

METHODS

A comprehensive search of the EMBASE and Medline databases was undertaken to identify randomised control trials (RCTs) involving PPN use in surgical patients published until July 30th 2022. Three domains of PPN use were reviewed including: PPN compared to crystalloid intravenous fluids on nutritional and clinical outcomes; PPN compared to Central PN (CPN) on nutritional outcomes and complications; and strategies to prevent thrombophlebitis associated with PPN.

RESULTS

The meta-analysis included 8 studies which included 698 patients. Use of PPN led to reduced post-operative weight loss (% body weight change) with a mean difference of -1.45% (95% CI -2.9 to -0.01, p = 0.05). There was no statistically significant difference in terms of length of stay, infectious/non-infectious complications, surgical site infections or phlebitis. 42 RCTs were included in the systematic review. 14 RCTs compared PPN to crystalloid infusion. There was significant heterogeneity in the trial populations, interventions and measured outcomes. Most trials found that PPN may improve nitrogen balance and positively impact nutritional markers. Quality of life and post-operative complications were either improved or no difference found in trials assessing these outcomes. Four RCTs showed that PPN is a safe and feasible alternative to CPN. 22 RCTs reported on measures that may impact on thrombophlebitis rates associated with PPN. These included lower osmolality of PPN solution, cyclical PPN delivery, use of a small gauge polyurethane cannula in an upper limb vein, addition of heparin/hydrocortisone to PPN solutions and placement of a GTN patch over infusion sites.

CONCLUSION

PPN is a safe and effective mode of delivery of peri-operative nutrition. It is a feasible short-term alternative to central-line delivered PN. There are a number of strategies to reduce thrombophlebitis associated with PPN use. Further high-quality RCTs are required to assess the use of PPN in contemporary surgical practice.

When Is Parenteral Nutrition Appropriate?

Parenteral nutrition (PN) represents one of the most notable achievements of modern medicine, serving as a therapeutic modality for all age groups across the healthcare continuum. PN offers a life-sustaining option when intestinal failure prevents adequate oral or enteral nutrition. However, providing nutrients by vein is an expensive form of nutrition support, and serious adverse events can occur. In an effort to provide clinical guidance regarding PN therapy, the Board of Directors of the American Society for Parenteral and Enteral Nutrition (ASPEN) convened a task force to develop consensus recommendations regarding appropriate PN use. The recommendations contained in this document aim to delineate appropriate PN use and promote clinical benefits while minimizing the risks associated with the therapy. These consensus recommendations build on previous ASPEN clinical guidelines and consensus recommendations for PN safety. They are intended to guide evidence-based decisions regarding appropriate PN use for organizations and individual professionals, including physicians, nurses, dietitians, pharmacists, and other clinicians involved in providing PN. They not only support decisions related to initiating and managing PN but also serve as a guide for developing quality monitoring tools for PN and for identifying areas for further research. Finally, the recommendations contained within the document are also designed to inform decisions made by additional stakeholders, such as policy makers and third-party payers, by providing current perspectives regarding the use of PN in a variety of healthcare settings.

Efficacy of hypocaloric parenteral nutrition for surgical patients: a systematic review and meta-analysis

BACKGROUND AND AIMS

Hypocaloric parenteral nutrition is an underfeeding strategy that lowers energy intake to around 20 kcal/kg/d. It is believed to achieve benefits by modulating metabolic responses and alleviating hyperglycemia. This study aims to systematically review the clinical efficacy of hypocaloric parenteral nutrition on surgical patients.

METHODS

Medline, SCI, Embase, Cochrane Library, Chinese Biomedicine Database (CBM) and China Knowledge Resource Integrated Database (CNKI) were searched for studies published before July 1, 2010. Randomized control trials (RCTs) that compared hypocaloric PN with standard or higher energy PN in surgical patients were identified and included. Methodological quality assessment was based on Cochrane Reviewers' Handbook and modified Jadad's Score Scale. Statistical software RevMan 5.0 was used for meta-analysis.

RESULTS

Five trials met all inclusion criteria and were included in the final meta-analysis. There were significant reductions in infectious complications (RR, 0.60; 95%CI 0.39-0.91, P = 0.02; I(2) = 38%) and length of hospitalization (LOS) associated with receiving hypocaloric PN (MD-2.49 days, 95%CI -3.88 to -1.11, P = 0.0004; I² = 48%). Stratified analysis of the smaller trials (<60) and larger trials demonstrated that the heterogeneity between trials was mainly associated with sample size. When smaller trials were excluded, hypocaloric PN was associated with reduction in infectious complications (RR, 0.21, 95%CI 0.06-0.72, P = 0.01, I2 = 0%) and shortening of LOS (MD, -2.32 days, 95%CI -3.72 to -0.93, P = 0.001, I² = 0%).

CONCLUSION

Hypocaloric parenteral nutrition may reduce infectious complications and the length of hospitalization in post-operative patients. However, this conclusion is tentative due to patient type and sample size. Furthermore, in terms of hypocaloric PN, the actual energy amount still varies a great deal (from 15 kcal/kg/d to 20 kcal/kg/d). This suggests that further research, including larger randomized clinical trials is required.