High-impact, low cost: Nutrition for improved surgical outcomes

The importance of protein during the perioperative period in improving patient's overall nutrition status.

20 May 2020

4 min

#Blog #Medical Nutrition #Global #Protein #Nutrition

Perioperative protein needs

The average patient undergoing elective surgery with no complications loses an average of 2 kg of lean body mass due to the catabolic, inflammatory effect of surgical stress.[1]

The loss of muscle mass is a significant contributor to post-surgical complications, as the body relies on an adequate amino acid supply to heal and recover. Protein is, therefore, a key nutrient in the preparation and recovery of the surgical patient.

Proper perioperative nutrition, with a focus on quality protein intake, can help prevent and modulate the stress response which can improve patient outcomes.

Research in geriatric patients shows that 28.2% of patients admitted to the hospital are already malnourished, which negatively impacts recovery from surgery, wound healing, and readmissions.[2]

After surgery, protein requirements remain high in order to promote wound healing and support the maintenance of lean muscle tissue.

There are many barriers to consuming enough protein after surgery such as bed rest reducing appetite, nausea, fatigue, or poor pain management.


The European Society for Clinical Nutrition and Metabolism recommends perioperative calorie needs of 25-30 kcal/kg and protein at 1.5g/kg

The European Society for Clinical Nutrition and Metabolism 

The European Society for Clinical Nutrition and Metabolism recommends perioperative calorie needs of 25-30 kcal/kg and protein at 1.5 g/kg.[3]

But, these calorie needs may vary depending on a patient’s medical history and comorbidities. For example, if a patient has additional wounds or malnutrition post-surgical protein needs may be as high as 2.2 g/kg which can be difficult to meet with food only.[4]

Simply telling a patient to eat more protein may not be adequate to preserve muscle mass or promote healing, and with food intake and weight remaining unchanged, supplements may be recommended to support muscle health.

A specific amino acid, called leucine, is a trigger for the synthesis of new protein through its ability to activate the mTOR pathway.

In practice, any nutritional supplement offered to a post-operative patient should contain at least 2.5 grams of leucine to help initiate the synthesis of new muscle tissue.[5,6,7]

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Maximizing nutrition with protein variety

The implementation of Enhanced Recovery After Surgery (ERAS) guidelines during the perioperative period has been found to significantly increase patient’s overall nutritional status and boost protein intake.

With the implementation of these protocols, there has been a 30-50% reduction in hospital length of stay and post-surgical complications.

Hospital readmissions and overall costs have been reduced in facilities that utilise ERAS protocols, which have been implemented in over 20 countries since their development.[8,9]

A comparison of conventional care versus ERAS post-operative guidelines found that protein intake in the latter was 16% greater due to the use of nutritional supplements. However, even with this improvement, protein intake remained at less than 60% of optimal.[9]

Although the ERAS guidelines can support nutritional status, there are several ways to increase oral intake in addition to simply providing dietary supplements. The first is increasing protein variety.

Humans love to enjoy different textures and flavours in their food. Although a chocolate-flavoured nutritional supplement may be desirable for a few days, patients may tire of the same flavour and/or the beverage format over time and reduce their adherence.

Hospital readmission's and overall costs have been reduced in facilities that utilise ERAS protocols

The Enhanced Recovery After Surgery (ERAS) guidelines 

Providing protein in various different formats and at different moments during and in-between meals can help increase food palatability and appetite. This may include:

  • High-protein milk-based oral supplements or refreshing water-based protein drinks
  • Eggs prepared in different ways
  • Protein-fortified bakery products
  • Mixing protein powder into hot cereal, soups, or casseroles
  • A variety of fortified flavoured yoghurts
  • Modular protein “shots”, like a drink or squeeze-pouches

Dietary supplements with complete amino acid profile of the product also should be considered for optimizing muscle maintenance and recovery.

Whey protein has naturally high leucine content, so, therefore, is able to stimulate muscle growth and repair, providing a great fortification option for normal foods and supplements to prepare for, and recover from surgery.[10,11]

Whey protein is an easy addition to many foods with its relatively neutral flavour, which is less likely to negatively impact the taste and texture of foods it is added to. 

How we can help  

We would love to collaborate with you on perioperaitve solutions. Get in contact with us and an NZMP expert will be in touch!


The author

Ana Reisdorf

Registered Dietitian Nutritionist

Ana Reisdorf, MS, RD is a Registered Dietitian Nutritionist and freelance writer with 12-years of experience in the field of nutrition and dietetics.

  • [1] Phillips BE, Smith K, Liptrot S, et al. Effect of colon cancer and surgical resection on skeletal muscle mitochondrial enzyme activity in colon cancer patients: a pilot study. J Cachexia Sarcopenia Muscle. 2013;4(1):71-77.
  • [2] Orlandoni P, Venturini C, Jukic Peladic N, et al. Malnutrition upon Hospital Admission in Geriatric Patients: Why Assess It?. Front Nutr. 2017;4:50.
  • [3] Weimann A, Braga M, Carli F, et al. ESPEN guideline: Clinical nutrition in surgery. Clin Nutr. 2017;36(3):623-650.
  • [4] Cox J, Rasmussen L. Enteral nutrition in the prevention and treatment of pressure ulcers in adult critical care patients. Crit Care Nurse. 2014;34(6):15-27; quiz 28.
  • [5] Witard OC, Wardle SL, Macnaughton LS, Hodgson 5. AB, Tipton KD. Protein Considerations for Optimising Skeletal Muscle Mass in Healthy Young and Older Adults. Nutrients. 2016;8(4):181.
  • [6] Phillips SM. Nutritional supplements in support of resistance exercise to counter age-related sarcopenia. Adv Nutr. 2015;6(4):452-460.
  • [7] Bauer J, Biolo G, Cederholm T, et al. Evidence-based recommendations for optimal dietary protein intake in older people: a position paper from the PROT-AGE Study Group. J Am Med Dir Assoc. 2013;14(8):542-559.9.
  • [8] Ljungqvist O, Scott M, Fearon KC. Enhanced Recovery After Surgery: A Review. JAMA Surg. 2017;152(3):292-298.
  • [9] Gustafsson UO, Scott MJ, Schwenk W, et al. Guidelines for perioperative care in elective colonic surgery: Enhanced Recovery After Surgery (ERAS(®)) Society recommendations. World J Surg. 2013;37(2):259-284.
  • [10] Yeung SE, Hilkewich L , Gillis C, Heine JA, Fenton TR. Protein intakes are associated with reduced length of stay: a comparison between Enhanced Recovery After Surgery (ERAS) and conventional care after elective colorectal surgery. Am J Clin Nutr. 2017;106(1):44.
  • [11] Tang JE, Moore DR, Kujbida GW, Tarnopolsky MA, Phillips SM. Ingestion of whey hydrolysate, casein, or soy protein isolate: effects on mixed muscle protein synthesis at rest and following resistance exercise in young men. J Appl Physiol. 2009;107(3):987-992.

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