Preoperative CHO Research Articles

Single-dose carbohydrate treatment in the immediate preoperative phase diminishes development of postoperative peripheral insulin resistance

Preoperative oral carbohydrate (CHO) treatment is known to reduce postoperative insulin resistance, but the necessity of a preoperative evening dose is uncertain. We investigated the effect of single-dose CHO treatment two hours before surgery on postoperative insulin sensitivity. Thirty two pigs (∼ 30 kg) were randomized to 4 groups (n = 8) followed by D-[6,6-(2)H2] glucose infusion and hyperinsulinemic-euglycemic step clamping. Two groups received a morning drink of 25 g carbohydrate (CHO/surgery and CHO/control). Animals in the other two groups were fasted overnight (fasting/surgery and fasting/control). Counter-regulatory hormones, free fatty acids (FFA) and liver and muscle glycogen content were measured serially. Glucose infusion rates needed to maintain euglycemia were higher after CHO/surgery than fasting/surgery during low (8.54 ± 0.82 vs. 6.15 ± 0.27 mg/kg/min, P < 0.05), medium (17.26 ± 1.08 vs. 14.02 ± 0.56 mg/kg/min, P < 0.02) and high insulin clamping (19.83 ± 0.95 vs. 17.16 ± 0.58 mg/kg/min, P < 0.05). The control groups exhibited identical insulin sensitivity. Compared to their respective controls, insulin-stimulated whole-body glucose disposal was significantly reduced after fasting/surgery (-41%, P < 0.001), but not after CHO/surgery (-16%, P = 0.180). CHO reduced FFA perioperatively (P < 0.05) and during the clamp procedures (P < 0.02), but did not affect hepatic insulin sensitivity, liver and muscle glycogen content or counter-regulatory hormone profiles. A strong negative correlation between peripheral insulin sensitivity and mean cortisol levels was seen in fasted (R = -0.692, P = 0.003), but not in CHO loaded pigs. Single-dose preoperative CHO treatment is sufficient to reduce postoperative insulin resistance, possibly due to the antilipolytic effects and antagonist properties of preoperative hyperinsulinemia on the suppressant actions of cortisol on carbohydrate oxidation.

The role of carbohydrate drinks in preoperative nutrition: comment 2

We read with interest the review of Jones et al looking at the role of CHO drinks in perioperative nutrition for elective colorectal surgery. However, we have some concerns regarding the rigour of assessment of elements of the evidence base and the authors’ accuracy in presentation of this evidence. The largest randomised controlled trial referenced (and one of only two that looked at clinical outcomes in patients undergoing colorectal surgery in the review) is that of Mathur et al. 1 The review by Jones et al states that Mathur et al showed CHO supplements reduced length of hospital stay. This is at odds with Mathur’s own conclusion: ‘Preoperative CHO treatment did not improve postoperative fatigue or length of hospital stay after major abdominal surgery.’ 1 Furthermore, the work of Svanfeldt et al 2 is misquoted in this review, suggesting it showed that: ‘whole-body protein did not change in the high CHO group whereas it was more negative in the low CHO group after surgery…’ Svanfeldt et al investigated whole-body protein kinetics via a stable isotope labelled amino acid technique and not whole-body protein. This protein kinetic study looked at changes in protein balance before and after colorectal surgery. Whole-body protein balance was shown to be negative at a set point in time during the preoperative fast and again at a set point during the early postoperative period. The rate of loss of protein mass at this instant was faster in the group receiving low dose preoperative CHO than in the high dose group. To interpret this as meaning whole-body protein did not change in the perioperative period in the group receiving high dose CHO is erroneous. While Yuill et al have shown a reduced loss of muscle mass postoperatively in patients receiving CHO, 3 this has been in upper gastrointestinal (GI) surgery and not colorectal surgery. Other studies such as that by Mathur et al 1 do measure total body protein in lower GI surgery but have not as yet demonstrated that CHO can significantly attenuate the perioperative loss of total body protein. We agree that measures to minimise the stress response to surgery will benefit our patients. Evidence exists that supports the implementation of ERAS programmes, 4 most of which include preoperative CHO supplementation. However, it is important for us to present in context an accurate evidence base supporting each component of ERAS to maximise the benefit to the patient with the minimum number of steps in the process. The case for CHO perioperative drink is not settled and should not become established as dogma (which applies to any other step in the process) until it is proven.

The role of carbohydrate drinks in preoperative nutrition: comment 1

Comment on Jones C, Badger SA, Hannon R. The role of carbohydrate drinks in preoperative nutrition for elective colorectal surgery. Ann R Coll Surg Engl 2011; 93: 504–507 doi 10.1308/147870811X13137608455136 I enjoyed reading and entirely agree with the findings of the review by Jones et al on the role of carbohydrate (CHO) drinks in preoperative nutrition for elective colorectal surgery but I offer a word of caution. No mention was made of the possible increased risk of surgical site infection (SSI) that may be caused by this action, even in non-diabetic patients. Tight control of perioperative blood sugar in patients who have diabetes is one of the high impact interventions advocated by the Department of Health to reduce the risk of SSI. 1 In addition, there is compelling evidence that poorly controlled, perioperative blood sugar, even in non-diabetic patients, may significantly increase deep sternal wound SSI rates in patients having cardiac surgery. 2 In these days of enhanced recovery after surgery (ERAS), the increasing use of a laparoscopic approach (particularly for elective colorectal surgery) and optimal use of anaesthesia 3 (both of which minimise the metabolic response to trauma) may make this caution unnecessary with regard to SSI. However, I should be interested to know if Jones et al found any increased incidence of SSI in their meta-analysis when preoperative CHO drinks had been used prior to open elective colorectal surgery. If this were found to be the case, closer control of blood sugar ought to be considered in the perioperative period.

Preservation of the gut by preoperative carbohydrate loading improves postoperative food intake

A carbohydrate (CHO) drink given preoperatively changes the fasted state into a fed state. The ESPEN guidelines for perioperative care include preoperative CHO loading and re-establishment of oral feeding as early as possible after surgery. An intestinal ischaemia reperfusion (IR) animal model was used to investigate whether preoperative CHO loading increases spontaneous postoperative food intake, intestinal barrier function and the catabolic response. Male Wistar rats (n = 65) were subjected to 16 h fasting with ad libitum water and: A) sham laparotomy (Sham fasted, n = 24); B) intestinal ischaemia (IR fasted, n = 27); and C) intestinal ischaemia with preoperatively access to a CHO drink (IR CHO, n = 14). Spontaneous food intake, intestinal barrier function, insulin sensitivity, intestinal motility and plasma amino acids were measured after surgery. The IR CHO animals started eating significantly earlier and also ate significantly more than the IR fasted animals. Furthermore, preoperative CHO loading improved the intestinal barrier function, functional enterocyte metabolic mass measured by citrulline and reduced muscle protein catabolism, as indicated by normalization of the biomarker 3-methylhistidine. Preoperative CHO loading improves food intake, preserves the GI function and reduces the catabolic response in an IR animal model. These findings suggest that preoperative CHO loading preserves the intestinal function in order to accelerate recovery and food intake. If this effect is caused by overcoming the fasted state or CHO loading remains unclear.

Preoperative carbohydrate loading for elective surgery: a systematic review and meta-analysis

It is unclear whether the preoperative administration of oral carbohydrates (CHO) is safe and effective, and therefore we herein evaluated the efficacy and adverse events associated with CHO for elective surgery. Comprehensive searches were conducted to identify randomized controlled trials (RCTs), which evaluated preoperative CHO for elective surgery. Two reviewers independently selected the trials, extracted data, and assessed the methodological qualities and evidence levels. The data were analyzed by the RevMan 5.0 software program. CHO increased the insulin and glucose levels on the first day after surgery higher than those in overnight fasting group (fifteen RCTs) and i.v. glucose infusion group (three RCTs). The pooled results of thirteen RCTs showed greater declines in the insulin level at the induction of anesthesia and a smaller increase in the glucose level at the end of surgery, and fewer decreases in the postoperative insulin sensitivity index in the CHO group were observed as compared to the placebo group. No aspiration was observed in any of the included studies. CHO appears to be safe, and may attenuate postoperative insulin resistance as compared to placebo. However, the quality of most of the published trials has been poor, and the evidence levels for most outcomes were low, so rigorous and larger RCTs are needed in the future.

The role of carbohydrate drinks in preoperative nutrition for elective colorectal surgery

Traditionally, patients have been fasted from midnight on the night before elective surgery. With the advent of the enhanced recovery programme for elective colorectal surgery, there has been a major change in established practice with patients able to continue with clear fluids up to two hours prior to surgery and solids up to six hours prior to surgery. It has been suggested that nutritional supplements in the immediate pre-operative period enhance post-operative recovery. The aim of this review was therefore critically to appraise the evidence available regarding the use of pre-operative carbohydrate (CHO) supplements for elective colorectal surgery. A literature search was performed using: PubMed, MEDLINE(®), Athens and Google Scholar. The following keywords were used: 'pre-operative', 'carbohydrate supplements', 'enhanced recovery' and 'colorectal surgery', singly or in combination. To ensure an up-to-date literature search, the search was restricted to the last ten years. To maximise the search, backward chaining of reference lists from retrieved papers was also undertaken. Only English language articles were included. The use of CHO drinks pre-operatively in colorectal surgery is both safe and effective. There is no increased risk of aspiration and it results in a shorter hospital stay, a quicker return of bowel function and less loss of muscle mass. On the basis of this evidence, the use of pre-operative CHO drinks should be standard in elective colorectal patients. Further research is nevertheless required for those with diabetes mellitus.

Preoperative conditioning with oral carbohydrate loading and oral nutritional supplements can be combined with mechanical bowel preparation prior to elective colorectal resection

Preoperative conditioning with oral fluid and carbohydrate (CHO) loading allows the patient to undergo surgery in the fed state and is associated with reduced postoperative insulin resistance. Further benefit may accrue from oral nutritional supplements (ONS) to counteract the fasting associated with mechanical bowel preparation (MBP). In this study we assess the ability to prescribe, dispense and have patients comply with a protocol combining preoperative ONS and CHO/fluid loading during MBP. One hundred and forty-seven patients undergoing elective left colonic or rectal resection were recruited to an Enhanced Recovery after Surgery (ERAS) programme. All patients were prescribed MBP (2 sachets Picolax). On the daytime prior to surgery, eligible patients were prescribed 2 x 200 ml of ONS (Fortijuice, Nutricia) and in the evening 800 ml oral CHO/fluid loading (Preop(R), Nutricia,). Patients were prescribed a further 400 ml of oral/CHO/fluid on the morning of surgery 2 h prior to induction of anaesthesia. Protocol compliance was audited prospectively. One hundred and forty-seven patients received MBP. Twenty-three patients were ineligible for oral CHO/fluid loading [diabetes (n = 22), allergy to lemon flavoured drinks (n = 1)]. Fourteen patients did not receive the preoperative CHO drinks due to failure to prescribe (n = 8) or dispense (n = 6). One hundred and ten patients were dispensed the combined ONS and CHO/fluid loading regimen, compliance rates were 83% with ONS, 80% with CHO/fluid loading and 74% with both. Approximately 74% of patients undergoing MBP can comply with preoperative conditioning with ONS and CHO/fluid loading. Prescription and dispensing requires close attention to detail.

Preoperative Oral Carbohydrate Administration to ASA III-IV Patients Undergoing Elective Cardiac Surgery

In this study we investigated the effects of preoperative oral carbohydrate administration on postoperative insulin resistance (PIR), gastric fluid volume, preoperative discomfort, and variables of organ dysfunction in ASA physical status III-IV patients undergoing elective cardiac surgery, including those with noninsulin-dependent Type-2 diabetes mellitus. Before surgery, 188 patients were randomized to receive a clear 12.5% carbohydrate drink (CHO), flavored water (placebo), or to fast overnight (control). CHO and placebo were treated in double-blind format and received 800 mL of the corresponding beverage in the evening and 400 mL 2 h before surgery. Patients were monitored from induction of general anesthesia until 24 h postoperatively. Exogenous insulin requirements to control blood glucose levels <or=10.0 mmol/L were used as a marker for PIR. Gastric fluid volume was measured by passive gastric reflux and preoperative discomfort using visual analog scales. Postoperative clinical and surgical data were recorded. Blood glucose levels and insulin requirements did not differ between groups. Patients receiving CHO and placebo were less thirsty compared with controls (P < 0.01 and P = 0.06, respectively). Ingested liquids did not cause increased gastric fluid volume or other adverse events. The CHO group required less intraoperative inotropic support after initiation of cardiopulmonary bypass weaning (P < 0.05). In conclusion, preoperative CHO administration before cardiac surgery does not affect PIR. Clear fluids reduce thirst and may be recommended as a safe procedure in ASA III-IV patients. Further research is indicated to investigate possible cardioprotective effects of preoperative CHO intake.