Being nutritionally prepared for surgery can help your patients experience better outcomes and a faster recovery. Perioperative nutrition – or how you nourish your body around the time of surgery – plays a crucial role in enhancing surgical outcomes and supporting how the body responds to the stress of a procedure. Research shows that optimal nutritional preparation can significantly improve recovery times and reduce complications, especially in patients who are not well nourished going into surgery or who live with chronic illness.^1-4

Though all macronutrients play essential roles, protein is especially vital for post-surgical recovery because it aids tissue repair, immune function, and muscle maintenance. By optimizing protein intake before surgery, healthcare providers can help patients be better equipped to withstand surgical stress, increase resilience, and reduce the risk of infection and other complications, including reduced time in the intensive care unit (ICU).^1,2,4

Key Nutrients in Perioperative Nutrition

Lack of good nutrition is a risk factor for healing and recovery post-surgery. Research shows that up to 50% of patients who have surgery are already experiencing malnutrition.^1,3-5 Unintended weight loss in the hospital occurs in up to two-thirds of patients and can be compounded by increased nutritional needs before and after surgery.^4,6 The need for fasting before and after surgery and the presence of inflammatory cytokines post-surgery – a natural part of the healing process – can drive weight loss, including lean body mass loss.^1,4,5 Helping your clients meet their caloric needs, with a focus on their macronutrient needs, is an important first step before and after surgery.^1,2 Even if a patient is going into surgery well-nourished, they can still optimize their recovery by focusing on several key nutrients, including protein, specific amino acids, and collagen. 

Protein

Adequate protein consumption in the weeks leading up to surgery is essential for building nutritional reserves that the body can draw upon during recovery. Studies show that increasing protein intake before surgery is highly beneficial. A journal article by Williams et al. about perioperative nutrition care for orthopedic surgical patients recommends a high-protein diet (1.2-2.0g/kg/day) for two to four weeks pre-surgery, especially for high-nutrition-risk patients.^4,7 In addition to increasing intake weeks prior, research also shows that (if cleared by the surgical team), 30g of protein 12 hours before surgery can create better outcomes.⁴ Protein helps promote wound healing, rebuild muscle, and reduce inflammation in the postoperative phase.³ Recommendations from the European Society for Clinical Nutrition and Metabolism (ESPEN) expert group and Enhanced Recovery After Surgery (ERAS) guidelines include a protein intake of 1.5–2.0 g/kg of body weight per day in the postoperative period to support maintaining muscle mass during recovery and to promote optimal healing.^5,8

Both plant and animal proteins can help patients meet their needs. Animal proteins have been studied more than plant proteins. Plant proteins have some limitations, such as lower digestibility, bioavailability, and amino acid profiles than animal proteins. However, studies on the impact of plant proteins on muscle strength and function have performed comparably to controls with animal proteins in studies, and evidence supports the fact that plant-based protein sources still help patients meet their protein needs.⁹

Studies show that education from healthcare providers about meeting protein needs helps patients with their intake. A study about nutrition education that’s provided by a registered dietitian nutritionist for patients preparing to undergo a total joint replacement found that 90% of patients who took a preoperative class increased their protein intake. In comparison, only 58% of those who didn’t take the class did.¹⁰

In addition to maximizing protein intake to meet increased needs after surgery, specific nutrients such as essential (or conditionally essential) amino acids and collagen can enhance recovery outcomes.


Specific Amino Acids and Collagen 

Arginine

A conditionally essential amino acid during stress or trauma post-surgery, arginine modulates immune function, hormone secretion, wound healing through increased collagen deposition, and endothelial function (the lining of blood vessels).^6,11 A meta-analysis on postoperative outcomes in patients with colorectal cancer (n=24 publications, 1883 patients) found significant improvements in immune function in patients supplemented with arginine. For example, immune markers and antibodies IgA increased by 0.45, IgG by 0.80, and IgM by 0.66 (standardized mean differences, SMD). White blood cells such as CD4+ T cell counts rose by 1.03 SMD, and the arginine group had fewer surgical site infections (relative risk reduction of -0.02), and shorter hospital stays (SMD = -0.15).¹¹ Intervention studies have used 8.5 – 30g oral or intravenous arginine.^6,11

Glutamine

Glutamine, like arginine, becomes a conditionally essential amino acid during illness and stress.⁶ It plays a multifaceted role in perioperative nutrition via protein synthesis, acid-base balance, ammonia metabolism, immune modulation, and the creation of cells, including lymphocytes, macrophages, and fibroblasts, which all play key roles in healing and recovery.^5,6 During stressful events like surgery, the body’s glutamine stores can deplete, impacting recovery and slowing wound healing.⁶ Supplementing with exogenous glutamine either orally or parenterally (intravenously) at 0.2 – 0.5g/kg/d has significantly reduced hospital stay duration, shortened wound healing time, and reduced infectious complications in many intervention studies.^2,5,6

Collagen

Collagen (the structural protein that makes up the body’s connective tissues) provides amino acids that contribute to tissue repair and skin integrity, which are vital for wound healing. Specifically, glycine, proline, and hydroxyproline create a triple helix structure that creates protein fibers.¹² Collagen also contains arginine, lysine, and glutamic acid.¹²  Collagen supplementation has been studied in advanced wound healing therapies for various types of chronic wounds, such as pressure ulcers, diabetic foot ulcers, and venous leg ulcers, as well as healing time post-surgery.¹³ The peptides (small pieces of collagen protein) in collagen appear to stimulate fibroblast growth (the most common cell type represented in connective tissue in the body), aiding the healing process.¹³

Exciting research also exists about the role of collagen supplementation for hospitalized people recovering from severe burns. A small randomized clinical trial (n=31 men) found that a hydrolyzed collagen-based supplement significantly improved wound healing and serum pre-albumin (a common nutrition status marker used in hospital settings) and clinically reduced hospital stay in patients.¹⁴ These patients were all on a 20-25% protein diet, and the intervention group received 36g of hydrolyzed bovine collagen for four weeks.

Takeaways for Healthcare Providers

Proactive nutritional planning can significantly impact surgical outcomes and recovery times. Educating patients on the importance of protein is essential, and healthcare providers can help their clients strategize how to meet their increased needs – up to 1.2–2.0 g/kg/d both pre-and postoperatively – through animal and/or plant-based protein sources. Practical strategies such as meal planning and tracking protein intake accurately can empower patients to meet their targets consistently.

The period surrounding a major surgical procedure can be taxing for both patients and their caregivers. Family support is often essential in optimizing nutritional intake and encouraging eating habits to support healing, such as consuming high-calorie/high-protein foods more frequently throughout the day or purchasing high-protein liquid nutrition supplements that are easy to consume and taste good, so patients want to drink them. Oral nutrition supplements have been shown to reduce the cost associated with hospitalization due to reduced complications and length of stay.⁴ A collaborative approach that involves the patient, family, caregivers, and healthcare team is crucial for managing the postoperative course and ensuring the patient receives optimal support.

References:

1. Martínez-Ortega AJ, Piñar-Gutiérrez A, Serrano-Aguayo P, et al. Perioperative nutritional support: a review of current literature. Nutrients. 2022;14(8):1601.
2. Ford KL, Prado CM, Weimann A, Schuetz P, Lobo DN. Unresolved issues in perioperative nutrition: a narrative review. Clinical Nutrition. 2022;41(7):1578-90.
3. Gillis C, Ljungqvist O, Carli F. Prehabilitation, enhanced recovery after surgery, or both? A narrative review. British journal of anaesthesia. 2022;128(3):434-48.
4. Hirsch KR, Wolfe RR, Ferrando AA. Pre- and Post-Surgical Nutrition for Preservation of Muscle Mass, Strength, and Functionality Following Orthopedic Surgery. Nutrients. 2021;13(5):1675.
5. Lobo DN, Gianotti L, Adiamah A, et al. Perioperative nutrition: Recommendations from the ESPEN expert group. Clinical nutrition. 2020;39(11):3211-27.
6. Arribas-López E, Zand N, Ojo O, Snowden MJ, Kochhar T. The effect of amino acids on wound healing: a systematic review and meta-analysis on arginine and glutamine. Nutrients. 2021;13(8):2498.
7. Williams DG, Wischmeyer PE. Perioperative nutrition care of orthopedic surgery patient. Techniques in Orthopaedics. 2020;35(1):15-8.
8. Golder HJ, Papalois V. Enhanced Recovery after Surgery: History, Key Advancements and Developments in Transplant Surgery. J Clin Med. 2021;10(8):1634.
9. Stoodley IL, Williams LM, Wood LG. Effects of Plant-Based Protein Interventions, with and without an Exercise Component, on Body Composition, Strength and Physical Function in Older Adults: A Systematic Review and Meta-Analysis of Randomized Controlled Trials. Nutrients. 2023;15(18):4060.
10. Riedel C, Venezia K. Attending a Pre-Op Class with a Nutrition Component Taught by a Registered
11. Dietitian Nutritionist Increases Patients Perioperative Protein Intake. Journal of the Academy of Nutrition and Dietetics. 2022;122(9):A9.
12. Ouyang Z, Chen P, Zhang M, Wu S, Qin Z, Zhou L. Arginine on immune function and post-operative obstructions in colorectal cancer patients: a meta-analysis. BMC cancer. 2024;24(1):1089.
13. Paul C, Leser S, Oesser S. Significant Amounts of Functional Collagen Peptides Can Be Incorporated in the Diet While Maintaining Indispensable Amino Acid Balance. Nutrients. 2019;11(5):1079.
14. Wang H. A review of the effects of collagen treatment in clinical studies. Polymers. 2021;13(22):3868.
15. Bagheri Miyab K, Alipoor E, et al. The effect of a hydrolyzed collagen-based supplement on wound healing in patients with burn: A randomized double-blind pilot clinical trial. Burns. 2020;46(1):156-163.