Our class of dietetic interns graduated in late June, so July is one of the few months of the year with no intern rotations or lectures. Life at a teaching hospital is never dull because the new physicians arrive in July, so we start getting to know everyone all over again. Our photo is along the bank of the Shenandoah River with the Blue Ridge Mountains in the distance.
Our journal club article for July dealt with the potential role of arginine-containing immunonutrition formulas used as part of an ERAS protocol.
Moya P, Soriano-Irigaray L, Ramirez JM, et al. Perioperative Standard Oral Nutrition Supplements Versus Immunonutrition in Patients Undergoing Colorectal Resection in an Enhanced Recovery (ERAS) Protocol: A Multicenter Randomized Clinical Trial (SONVI Study). Medicine . 2016 May;95(21):e3704.
This was a multicenter, randomized, single-blind study comparing an “immune-enhancing” feeding (arginine, omega-3 FA, nucleotides) with a standard high-protein feeding consumed for 7 days prior to colorectal surgery, and 5 days postoperatively. Patients were asked to consume 400 mLs of either the immune-enhancing or standard product in addition to their usual diet and to record their supplement use in a compliance diary. All patients received the same ERAS protocol of 4 carbohydrate-rich drinks (800 mL) 1 day prior to surgery and 2 additional drinks (400 mLs each) on the morning of surgery. Epidural anesthesia and opioid-free pain control was used, nasogastric tubes were avoided, patients were mobilized, and were provided with oral fluids early.
The primary outcome of the study was the postoperative 30-day morbidity rate, which was defined as any deviation from the normal postoperative course and was divided into minor and major complications. Minor complications included wound infection that were treated at the bedside, urinary tract infection, and postoperative ileus. Major complications included anything potentially life-threatening and those requiring surgical, endoscopic, or radiological intervention, such as anastomotic leak, abdominal abscess, or pneumonia. Surgical site infection was classified as superficial or deep incisional infection. Length of stay and readmission rates/causes were also documented.
Inclusion and Exclusion Criteria:
Age ≥18 years, scheduled for surgery for colorectal cancer, normal nutrition status, and provided written consent.
Need for emergency surgery, American Society of Anesthesiologists (ASA) physical status IV (severe systemic disease that is a constant threat to life); renal failure; receiving immunomodulatory or nutritional supplements; hypersensitivity to arginine, omega-3 fatty acids, or nucleotides; inability to consume oral nutrition; psychiatric disorders; HIV; pregnancy; bowel obstruction; or uncontrolled infection.
Of 264 patients screened, none were excluded so 264 were randomized. Seven patients did not receive the study intervention and 13 opted not to participate after the study started, so that ultimately data from 122 patients in each group were analyzed. Baseline characteristics were similar between groups, and the investigators reported that all patients were compliant with 400 mLs of supplement intake preoperatively.
Laparoscopic surgery was utilized in 74.6% (n = 182) of patients and 25.4% (62) underwent open surgery, with 8.8% of the laparoscopic procedures requiring conversion to laparotomy. There were no substantial differences in types of surgery, operative time, or estimated intraoperative blood loss between the 2 groups. There were no differences between groups in the volume of postoperative drinks consumed (211 ± 12.68 mL standard and 198 ± 12.56 mL for immunonutrition). The median length of the postoperative hospital stay was 5 days and 3.27% (8 patients) were readmitted following discharge with no difference between groups.
The most common surgical complications were paralytic ileus (10.65%; 26) and anastomotic leakage (6.55%; 16), and the most common infectious complications were surgical site infection (superficial and deep incisional site infection (11%; 27) and organ/space infection (1.6%; 3)), urinary tract infection (0.8%; 2), and respiratory infection (2%; 5).
There were significantly fewer complications in the immunonutrition group than the standard supplement group, primarily due to a significant decrease in infectious complications (23.8% vs. 10.7%, P = 0.0007). Among the infectious complications, surgical site infection was significantly less in the immunonutrition supplement group (17.2% vs. 5.7%, P = 0.0005). There was no mortality in any patient during the study period.
“….the implementation of ERAS protocols including immunonutrient-enriched supplements reduces complications in patients undergoing colorectal resection.”
The strong points of this study include the multicenter design and the fact that patients had a similar diagnosis and procedure on a similar anatomical area. However, this study was only single-blind, and diagnosis of postoperative complications often requires some degree of subjective/clinical judgement.
Although the standard and immunonutrition supplements did not have identical calorie/protein composition, the limited volume provided (400mLs/day) meant that there was only a 100 kcal/8gm protein per day difference between groups. Considering that patients consumed these supplements in addition to their normal food intake, our group thought the difference in macronutrient composition between the supplements to be a minor point.
This study relied on patient-reported compliance for the preoperative supplement use. The investigators reported that preoperative compliance was 100%, and I have difficulty believing that all 244 patients drank every drop of supplement for 7 days pre-procedure. Nonetheless, if the amounts consumed really decrease infectious complications, this may be a worthwhile intervention. Postoperative supplement compliance was only about 50% (205 mLs/day) and 23 patients had no supplement postoperatively, so we discussed the possibility that these results may primarily reflect the effects of the preoperative supplementation.
The authors point out in the discussion section that the incidence of infectious complications was less than predicted for the power analysis, therefore it may require a study with more participants to have confidence that the differences in surgical complications between groups were not a result of chance.
Our Take Home Message(s)
- Perioperative immunonutrition containing arginine, fish oil, and nucleotides may reduce infectious complications in well-nourished adults with colorectal cancer undergoing large bowel resection.
- Further studies will be required to know exactly what nutrients and what dose are the most effective to improve outcomes after colorectal surgery.
Other News on the UVAHS GI Nutrition Website: (www.ginutrition.virginia.edu):
Upcoming Webinars 2016:
September 20: Small Bowel Intestinal Overgrowth (registration now open)
November 16: Essential Fatty Acid Deficiency
December (date TBA): Fluids in the ICU
Latest Practical Gastroenterology article:
Vitamin D Deficiencies in Patients with Disorders of the Digestive System: Current Knowledge and Practical Considerations 2016;XL(7):36-43.
Joe Krenitsky MS, RDN
PS – Please feel free to forward on to friends and colleagues.