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An ERP starts in a well functioning preoperative clinic. The goal of preoperative optimization is to improve physiologic reserve to better tolerate the incoming stress of surgery.
Nutrition: Patients should be referred to a nutritionist if they are at risk for malnutrition and provided with supplementation to optimize stores preoperatively. Routine use of oral nutritional supplements for well-nourished patients does not seem to confer any benefit (1).
Glycemic control: Hyperglycemia is a risk factor for complications and patients with poorly controlled diabetes should be identified with HBA1C and optimized in conjunction with endocrinology. While blood glucose should be checked the morning of the surgery and controlled perioperatively, the optimal glycemic target has not been identified (2).
Older patients should be screened for delirium risk, cognitive ability and frailty (3).
Smoking increases the risk of pulmonary complications, incisional complications and anastomotic leak after colorectal surgery (4). Intensive interventions that begin at least 4 weeks prior to surgery are more likely to have an impact on reducing complications than shorter interventions (5).
Alcohol: Postoperative complications are increased in heavy users of alcohol (>3 alcohol units per day) (6). Intensive interventions aimed at complete cessation may reduce complications (7).
For more information, see Chapter 3: Medical Optimization and Prehabilitation in The SAGES / ERAS® Society Manual of Enhanced Recovery Programs for Gastrointestinal Surgery
References
1. Burden S, Todd C, Hill J, Lal S. Pre-operative nutrition support in patients undergoing gastrointestinal surgery. Cochrane Database Syst Rev. 2012 Nov 14;11:CD008879.
2. Buchleitner AM1, Martínez-Alonso M, Hernández M, Solà I, Mauricio D. Perioperative glycaemic control for diabetic patients undergoing surgery. Cochrane Database Syst Rev. 2012 Sep 12;9:CD007315.
3. Chow WB, Rosenthal RA, Merkow RP, Ko CY, Esnaola NF; American College of Surgeons National Surgical Quality Improvement Program; American Geriatrics Society. Optimal preoperative assessment of the geriatric surgical patient: a best practices guideline from the American College of Surgeons National Surgical Quality Improvement Program and the American Geriatrics Society. J Am Coll Surg. 2012 Oct;215(4):453-66
4. Sharma A, Deeb AP, Iannuzzi JC, Rickles AS, Monson JR, Fleming FJ. Tobacco smoking and postoperative outcomes after colorectal surgery. Ann Surg. 2013 Aug;258(2):296-300.
5. Thomsen T, Villebro N, Møller AM. nterventions for preoperative smoking cessation. Cochrane Database Syst Rev. 2014 Mar 27;3:CD002294.
6. Tønnesen H, Nielsen PR, Lauritzen JB, Møller AM. Smoking and alcohol intervention before surgery: evidence for best practice. Br J Anaesth. 2009 Mar;102(3):297-306
7. Oppedal K1, Møller AM, Pedersen B, Tønnesen H. Preoperative alcohol cessation prior to elective surgery. Cochrane Database Syst Rev. 2012 Jul 11;7:CD008343.
