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Background & Aims: Insulin resistance and chronic inflammation have been reported in patients with cancer. However, many of the underlying mechanisms and associations are yet to be unveiled. We examined both the level of insulin sensitivity and markers of inflammation in patients with colorectal cancer for comparison to controls., Methods: Clinical exploratory study of patients with colorectal cancer (n = 20) and matched controls (n = 10). Insulin sensitivity was quantified using the hyperinsulinemic normoglycemic clamp and blood samples were taken for quantification of several key, both intra- and extracellular, inflammatory markers. We analysed the differences in these parameters between the two groups., Results: Patients exhibited both insulin resistance (M-value, patients median (Mdn) 4.57 interquartile range (IQR) 3.49-5.75; controls Mdn 5.79 (IQR 5.20-6.81), p = 0.049), as well as increased plasma levels of the pro-inflammatory cytokines IL-1β (patients Mdn 0.48 (IQR 0.33-0.58); controls Mdn 0.36 (IQR 0.29-0.42), p = 0.02) and IL-6 (patients Mdn 3.21 (IQR 2.31-4.93); controls Mdn 2.16 (IQR 1.50-2.65), p = 0.02). The latter is present despite an almost two to three fold decrease (p < 0.01) in caspase-1 activity, a facilitating enzyme of IL-1β production, within circulating immune cells., Conclusion: Patients with colorectal cancer displayed insulin resistance and higher levels of plasma IL-1β and IL-6, in comparison to matched healthy controls. The finding of a seemingly disconnect between inflammasome (caspase-1) activity and plasma levels of key pro-inflammatory cytokines in cancer patients may suggest that, in parallel to dysregulated immune cells, tumour-driven inflammatory pathways also are in effect., Competing Interests: Declaration of competing interest Authors declare that they have no competing interests., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background & Aim: Surgery causes development of insulin resistance. Women undergoing hysterectomy have different female sex hormonal status, ranging from premenopausal to postmenopausal. The aim of the study was to explore the relation between the female sex hormones and insulin resistance (IR%) after hysterectomy., Methods: A secondary analysis from a randomised controlled single-centre study at the Department of Obstetrics and Gynaecology, Örebro University Hospital, Sweden. Twenty women were randomised to robot-assisted laparoscopic or abdominal hysterectomy. Blood were drawn before and after surgery for measurement of oestrogens, progesterone, and gonadotropins alongside determination of insulin sensitivity using the hyperinsulinemic normolycaemic clamp., Results: Female sex hormonal status was not correlated to insulin sensitivity before operation. Premenopausal women developed more IR% than postmenopausal women (p = 0.012). Premenopausal women also showed a significant decrease in absolute levels of oestradiol (E2) (p = 0.016), and the relative decrease in E2 from preoperative to postoperative values (E2%) was significantly higher (p = 0.001). There was a significant positive correlation in the entire study population between E2% and IR% (r = 0.72, p = 0.001, r 2 0.51) that remained when adjusted for age (p = 0.028), BMI (p = 0.001), and preoperative insulin sensitivity (p = 0.011) separately., Conclusions: Premenopausal women developed a higher degree of postoperative insulin resistance that was associated with a parallel relative change in oestradiol levels compared with the postmenopausal women. It remains unclear whether these are independent phenomena in the overall stress response or whether a causal relationship exists., (Copyright © 2018 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background & Aims: Surgery causes inflammatory and metabolic responses in the body. The aim of the study was to investigate whether robotic-assisted total laparoscopic hysterectomy induces less insulin resistance than abdominal hysterectomy, and to compare inflammatory response and clinical recovery between the two techniques., Methods: A randomised controlled study at the Department of Obstetrics and Gynaecology, Örebro University Hospital, Sweden. Twenty women scheduled for a planned total hysterectomy with or without salpingo-oophorectomy between October 2014 and May 2015, were randomly allocated to robotic-assisted total laparoscopic hysterectomy or abdominal hysterectomy. Insulin resistance after surgery was measured by the hyperinsulinemic normoglycaemic clamp method, inflammatory response measured in blood samples, and clinical recovery outcomes registered., Results: There were no differences in development of insulin resistance between the robotic group and the abdominal group (mean ± SD: 39% ± 22 vs. 40% ± 19; p = 0.948). The robotic group had a significantly shorter hospital stay (median 1 vs. 2 days; p = 0.005). Inflammatory reaction differed; in comparison to the robotic group, the abdominal group showed significantly higher increases in serum interleukin 6 levels, white blood cell count and cortisol from preoperative values to postoperative peak values., Conclusions: Robotic laparoscopic surgery reduced inflammatory responses and recovery time, but these changes were not accompanied by decreased insulin resistance., Clinical Trial Registration: www.ClinicalTrials.gov Identifier no NCT02291406., (Copyright © 2016 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.)

Background: Patients receiving a carbohydrate drink (CHO) before major abdominal surgery display improved insulin sensitivity postoperatively and increased proteolysis of IGFBP-3 (IGFBP-3-PA) compared to patients undergoing similar surgery after overnight fasting., Aims: We hypothesized that serum IGFBP-3-PA increases bioavailability of circulating IGF-I and preserves insulin sensitivity in patients given CHO., Design: Matched control study., Methods: At Karolinska University Hospital, patients given CHO before major elective abdominal surgery (CHO,n = 8) were compared to patients undergoing similar surgical procedures after overnight fasting (FAST,n = 10). Results from two different techniques for determination of free-dissociable IGF-I (fdIGF-I) were compared with changes in IGFBP-3-PA and insulin sensitivity., Results: Postoperatively, CHO displayed 18% improvement in insulin sensitivity (hyperinsulinemic clamp) and increased IGFBP-3-PA vs. FAST. As determined by IRMA, fdIGF-I increased by 48 ± 25% in CHO while fdIGF-I decreased by 13 ± 18% in FAST (p < 0.01 vs. CHO, when corrected for duration of surgery). However, fdIGF-I determined by ultra-filtration decreased similarly in both groups (-22 ± 8% vs. -25 ± 8%, p = 0.8) and IGFBP-1 increased similarly in both groups. Patients with less insulin resistance after surgery demonstrated larger increases in fdIGF-I by IRMA (r = 0.58, p < 0.05). Fifty-three % of the variability of the changes in fdIGF-I by IRMA could be explained by changes in IGFBP-3-PA and total IGF-I levels (p < 0.05), while IGFBP-1 did not contribute significantly., Conclusion: During conditions when serum IGF-I bioavailability is regulated by IGFBP-3 proteolysis, measurements of fdIGF-I by IRMA is of physiological relevance as it correlates with the associated changes in insulin sensitivity., (Copyright © 2015 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.)

Background & Aims: In elective surgery, postoperative hyperglycaemia and insulin resistance are independent risk factors for complications. Since the simpler HOMA method has been used as an alternative to the hyperinsulinemic normoglycemic clamp in studies of surgery induced insulin resistance, we compared the two methods in patients undergoing elective surgery., Methods: Data from 113 non-diabetic patients undergoing elective surgery were used. Insulin sensitivity, both before and after surgery, was quantified by the clamp and HOMA. Pre- and postoperatively, the results of the clamp were compared to HOMA using regression- and correlation analysis. Degree of agreement between the methods was studied using weighted linear kappa and the Bland-Altman test., Results: Both the clamp and HOMA recorded a mean relative reduction in insulin sensitivity of 39 ± 24% and 39 ± 61% respectively after surgery; with significant correlations (p < 0.01) for pre- and post-operative measures as well as for relative changes. However r(2) values were low: 0.04, 0.07 and 0.03 respectively. The degree of agreement for the relative change in insulin sensitivity using the Bland-Altman test gave a mean of difference 0% but "limits of agreement" (± 2SD) was ± 125%. This poor inter-method agreement was consolidated by a weighted linear kappa value of 0.18., Conclusion: While the hyperinsulinemic euglycemic clamp measures the postoperative changes in insulin sensitivity, HOMA measures something different. Data using the HOMA method must therefore be interpreted cautiously and is not interchangeable with data obtained from the clamp., (Copyright © 2014 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.)

Background & Aims: Postoperative insulin resistance and the consequent hyperglycemia affects clinical outcome. Insulin sensitivity may be modulated by preoperative nutrition, adequate pain management and minimal invasive surgery. This study aims to disclose the impact of perioperative glucose control on postoperative insulin resistance., Methods: Twenty patients scheduled for elective open hepatectomy were enrolled in this prospective, randomized study. In the treatment group (n = 9) insulin was administered intravenously to keep blood glucose between 6 and 8 mmol/l during surgery. The control group (n = 8) received insulin if blood glucose >14 mmol/l. Insulin sensitivity was measured by a hyperinsulinemic normoglycemic clamp (0.8 mU/kg/min), performed on all patients both on the day before surgery and immediately postoperatively. Plasma cortisol, insulin and C-peptide were measured., Results: There was a significant difference in mean glucose value during surgery. In the control group 8.8 mmol/l (SD 1.5) vs. 6.9 mmol/l (SD 0.4) in the treated group, p = 0.003. In the control group insulin sensitivity decreased to 21.9% ± 16.2% of the preoperative value and in the insulin treated group to 46.8 ± 15.5%, p < 0.005. Insulin levels were significantly higher in the treatment group as well as consequently lower C-peptide levels., Conclusions: This trial revealed a significant difference in postoperative insulin resistance in the group treated with insulin during surgery., (Copyright © 2012 Elsevier Ltd and European Society for Clinical Nutrition and Metabolism. All rights reserved.)

This lecture reviews the current understanding of how insulin resistance, as a marker of the metabolic stress, is involved in recovery after major surgery. Insulin resistance develops as a graded response related to the magnitude of the operation. It lasts for weeks after medium-size surgery and affects all parts of body metabolism. Although hyperglycemia develops, muscle and fat uptake is reduced and other non-insulin-sensitive cells have an increase in glucose uptake as a result of the elevated glucose levels. Reduced glucose uptake and storage in muscle along with loss of lean body mass help explain reduced muscle function that will impair mobilization. The increased uptake of glucose in non-insulin-sensitive cells is involved in the development of several of the most common postoperative complications, including infections and cardiovascular problems. Many of the perioperative treatments in use are outdated, and modern care involves a multimodal approach with several treatments, such as preoperative carbohydrate treatment instead of overnight fasting, continuous epidural anesthesia for postoperative pain care, early feeding, and mobilization, all of which affect insulin by reducing the stress and enhancing recovery. Most of the previous mandatory catabolic responses to surgery can be avoided, resulting in substantially faster recovery and fewer complications. Methods to implement these modern treatments have been developed and used in Europe, resulting in improved care and shorter length of stay.

Purpose of Review: This article reviews the recent research on perioperative nutrition in digestive tract surgery in the light of modern perioperative care principles, that is, enhanced recovery after surgery (ERAS). Four major directions of research emerge: detecting malnutrition, perioperative hyperglycemia/insulin resistance, enteral/parenteral nutrition and immunonutrition., Recent Findings: For preoperative nutritional screening/assessment, current data cannot single out superiority for SGA questionnaire, nutritional risk score, Reilly's nutritional risk score or nutritional risk index in the ability to predict nutrition-related complications. The use of ERAS elements to reduce surgical stress and preclude postoperative insulin resistance has recently been clearly linked to reductions in adverse outcomes. There are specific situations in which enteral nutrition is contraindicated and criterias for preoperative and postoperative parenteral nutrition in undernourished patients are defined in guidelines recently available. Several controlled randomized studies and systematic reviews indicate that immune nutrition formulas reduce both morbidity and length of stay after major abdominal surgery., Summary: To reduce surgical stress, insulin resistance, unnecessary protein losses and postoperative complications, the use of an ERAS protocol is important. Current data shows that the use of perioperative immunonutrition diets for major abdominal surgery is beneficial. Further research on nutritional assessment tools to predict who is at risk for postoperative complications is needed.

Context: The mechanisms behind postoperative insulin resistance and impaired glucose utilization are not fully understood., Objective: In this study, we aimed to specifically evaluate the transcription profile of genes in the insulin and adipokine signaling pathways in sc and omental adipose tissue after surgical injury., Design: Relative expression of 21 target genes was analyzed in both sc and omental adipose tissue sampled at the beginning and at the end of operation., Setting: The study was conducted at a university-affiliated hospital., Patients: Twelve nondiabetic patients [seven females; age, 65 (range, 46-72) yr; body mass index, 24.8 (16.5-29.8) kg/m(2)] undergoing major abdominal surgery were included., Main Outcome Measurements: The changes in mRNA levels were analyzed., Results: After surgery, both sc and omental adipose tissue mRNA levels of genes involved in the IL6 and nicotinamide phosphoribosyltransferase pathways were increased, whereas mRNA levels of insulin receptor substrate 1 and adiponectin were reduced (P < 0.05). TNF pathway genes were differently regulated between sc and omental adipose tissue, and glucose transporter 4 mRNA levels were decreased only in omental adipose tissue., Conclusions: The transcriptional output of pivotal inflammatory and insulin signaling pathway genes is altered after surgery, and this pattern differs between different fat depots. This could be of importance for the metabolic aberrations associated to postsurgical complications, such as insulin resistance and hyperglycemia.

The concept of preoperative overnight fasting was challenged and proved to have no benefits over allowing patients to drink clear fluids up until 2 h before surgery. This led to changes in the guidelines for preoperative fasting in many countries around the world. This concept has more recently been developed further. Mounting evidence indicates that instead of being operated in the traditional overnight fasted state, undergoing surgery in the carbohydrate-fed state has many clinical benefits. Many of these clinical effects can be related to reduced postoperative insulin resistance by preoperative carbohydrate loading. This article summarises the present understanding of the mechanisms behind the positive clinical effects and gives an overview of the information available regarding the clinical effects of this treatment. Finally, the article summarises the most recently published national guidelines on preoperative fasting routines where preoperative carbohydrates are recommended for use before a major surgery. These are to be considered for all patients allowed to drink clear fluids and undergoing elective surgery.

Background & Aims: Postoperative insulin resistance, resulting in hyperglycemia, is strongly associated to morbidity and mortality in surgical patients but the underlying mechanisms are unclear. As increasing data suggests a link between inflammation and insulin resistance, we aimed to evaluate if the expression of inflammatory and insulin signaling genes is regulated in skeletal muscle during surgery., Methods: Eight patients (4 females, 63 [46-69] years, body mass index 25.5 [16.5-29.8]kg/m(2)) undergoing major abdominal surgery were included. Biopsies from m. rectus abdominis were obtained at the beginning and at the end of the operation. mRNA levels of 45 genes were analyzed., Results: The time elapsed between the two biopsies was 224 (198-310) min. An increased (p<0.05) expression was noted for genes encoding both inflammatory mediators, such as interleukin 6, tumor necrosis factor, and nuclear factor of kappa light polypeptide gene enhancer in B cells, and metabolic regulators, such as peroxisome proliferator-activated receptor delta, while the analysis did not detect significant expression changes of the insulin signaling pathway genes., Conclusions: The observed gene expression changes in skeletal muscle during surgery occurred mainly in inflammatory pathways, suggesting a possible role for inflammation in the development of postoperative insulin resistance.

Purpose of Review: Interest in stress-induced insulin resistance has increased during the past 5 years. Relevant clinical and mechanistic investigations during the past year will be reviewed., Recent Findings: Recent trials of intensive insulin therapy in intensive care units have brought attention to a high incidence of hypoglycemic episodes with such treatment. The clinical relevance of such hypoglycemia has been shown to be minor, however. Furthermore, animal and in-vitro work further supports the finding that glucose control, rather than glycemia-independent effects of insulin, is the primary mechanism of action of intensive insulin therapy. In elective surgery, cohort studies show an association between intraoperative hyperglycemia and postoperative morbidity. Beneficial effects of preoperative oral carbohydrate treatment on immunocompetence and cardiac contractility have been demonstrated. Laparoscopic segmental colectomy was associated with considerably attenuated derangements in glucose metabolism compared with conventional, open surgery., Summary: Better methods of insulin dosing and administration and glucose monitoring are warranted to further minimize the risks of intensive insulin therapy. In elective surgery, perioperative measures such as preoperative oral carbohydrate treatment and laparoscopic techniques attenuate metabolic and other physiological derangements and such methods should be integrated into perioperative care protocols to minimize morbidity and enhance recovery.

Objective: We compared the metabolic effects of postoperative total parenteral nutrition (TPN) and hypocaloric glucose after treatment with oral carbohydrates preoperatively and epidural anesthesia to proactively minimize postoperative insulin resistance., Methods: Thirteen patients undergoing colorectal resections were given oral carbohydrates preoperatively and epidural anesthesia and randomized to TPN or hypocaloric glucose during and after surgery. Insulin sensitivity (hyperinsulinemic clamp [0.8 mU x kg(-1) x min(-1)], normoglycemic clamps [4.5 mM]), and glucose kinetics (6,6(2)H2-D-glucose), were studied before and on postoperative day 3. Indirect calorimetry was performed and nitrogen excretion in urine was measured. Values are presented as mean +/- standard deviation. Analysis of variance, planned comparison, and Bonferroni's correction were used for statistical analysis., Results: Three days after surgery insulin-stimulated whole-body glucose disposal decreased by 24 +/- 11% versus 28 +/- 23% in patients receiving TPN and hypocaloric glucose, respectively (P < 0.05 for both, not significant between groups). Endogenous glucose production during insulin stimulation was increased only in the glucose group after surgery (P < 0.05 versus before). After surgery, insulin-stimulated glucose oxidation was higher after treatment with TPN, whereas fat oxidation was lower (P < 0.05 for both versus glucose treatment). Fat oxidation increased in the glucose group at basal after surgery (P < 0.05 versus before). Nitrogen balance was less negative after treatment with TPN (P < 0.01)., Conclusions: Treatment with TPN does not seem to improve postoperative peripheral insulin sensitivity in patients with minor insulin resistance after pretreatment with preoperative carbohydrates and perioperative epidural anesthesia. Hypocaloric nutrition results in changes in substrate utilization and nitrogen balance resembling starvation, whereas TPN attenuates these changes.

Background and Aims: Preoperative intake of a clear carbohydrate-rich drink reduces insulin resistance after surgery. In this study, we evaluated whether this could be related to increased insulin sensitivity at the onset of surgery. Furthermore, we aimed to establish the optimal dose-regimen., Methods: Six healthy volunteers underwent hyperinsulinaemic (0.8 mU/kg/min), normoglycaemic (4.5 mmol/l) clamps and indirect calorimetry on four occasions in a crossover-randomised order; after overnight fasting (CC), after a single evening dose (800 ml) of the drink (LC), after a single morning dose (400 ml, CL) and after intake of the drink in the evening and in the morning before the clamp (LL). Data are presented as mean+/-SD. Statistical analysis was performed using the Student's t-test and ANOVA., Results: Insulin sensitivity was higher in CL and LL (9.2+/-1.5 and 9.3+/-1.9 mg/kg/min, respectively) compared to CC and LC (6.1+/-1.6 and 6.6+/-1.9 mg/kg/min, P<0.01 vs. CL and LL)., Conclusions: A carbohydrate-rich drink enhances insulin action 3 h later by approximately 50%. Enhanced insulin action to normal postprandial day-time level at the time of onset of anaesthesia or surgery is likely to, at least partly, explain the effects on postoperative insulin resistance.

Background & Aims: Postoperative metabolism is characterised by insulin resistance and a negative whole-body nitrogen balance. Preoperative carbohydrate treatment reduces insulin resistance in the first day after surgery. We hypothesised that preoperative oral carbohydrate treatment attenuates insulin resistance and improves whole-body nitrogen balance 3 days after surgery., Methods: Fourteen patients undergoing total hip replacement were double-blindly randomised to preoperative oral carbohydrate treatment (12.5%, 800 + 400 ml, n = 8) or placebo (n = 6). Glucose kinetics (6,6-D2-glucose), substrate utilisation (indirect calorimetry) and insulin sensitivity (hyperinsulinaemic-euglycaemic clamp) were measured preoperatively and on the third day after surgery. Nitrogen losses were monitored for 3 days after surgery. Values are mean (SEM). Analysis of variance (ANOVA) statistics were used., Results: Endogenous glucose release during insulin infusion increased after surgery in the placebo group. Preoperative carbohydrate treatment, as compared to placebo, significantly attenuated postoperative endogenous glucose release (0.69 (0.07) vs. 1.21 (0.13)mg kg(-1) x min(-1), P < 0.01), while whole-body glucose disposal and nitrogen balance were similar between groups., Conclusions: While insulin resistance in the first day after surgery has previously been characterised by reduced glucose disposal, enhanced endogenous glucose release was the main component of postoperative insulin resistance on the third postoperative day. Preoperative carbohydrate treatment attenuated endogenous glucose release on the third postoperative day., (Copyright 2004 Elsevier Ltd.)

Insulin resistance develops as a response to virtually all types of surgical stress. There is an increasing body of evidence that suggests that insulin resistance in surgical stress is not beneficial for outcome. A recent large study in intensive-care patients showed that aggressive treatment of insulin resistance using intravenous insulin reduced mortality and morbidity substantially. Similarly, in burn patients, intensive insulin and glucose treatment has been shown to improve N economy and enhance skin-graft healing. In surgical patients insulin resistance has been characterized in some detail, and has been shown to have many similarities with metabolic changes seen in patients with type 2 diabetes. This finding may be important since insulin resistance has been shown to be one independent factor that influences length of stay. When patients about to undergo elective surgery have been treated with glucose intravenously or a carbohydrate-rich drink instead of overnight fasting, insulin resistance was reduced by about half. A small meta-analysis showed that when post-operative insulin resistance was reduced by pre-operative carbohydrates, length of hospital stay was shortened. Overnight intravenous glucose at high doses improved post-operative N economy. This type of treatment has also been shown repeatedly to reduce cardiac complications after open-heart surgery. Furthermore, if the carbohydrates are given as a drink pre-operatively, pre-operative thirst, hunger and anxiety are markedly reduced. In summary, preventing or treating insulin resistance in surgical stress influences outcome. Fasting overnight is not an optimal way to prepare patients for elective surgery. Instead, pre-operative carbohydrates have clinical benefits.

The aim of this present investigation was to study the relationship between the reduction in insulin sensitivity accompanying 5 days of treatment with growth hormone (GH; 0.05 mg.24 h(-1).kg(-1)) and intracellular substrate oxidation rates in six healthy subjects, while maintaining glucose flux by a constant glucose infusion and adjusting insulin infusion rates to achieve normoglycaemia (feedback clamp). Protein synthesis rates in skeletal muscle (flooding dose of L-[(2)H(5)]phenylalanine) were determined under these conditions. We also compared changes in insulin sensitivity after GH treatment with simultaneous changes in energy requirements, protein synthesis rates, nitrogen balance, 3-methylhistidine excretion in urine, body composition and the hormonal milieu. After GH treatment, 70% more insulin was required to maintain normoglycaemia (P<0.01). The ratio between glucose infusion rate and serum insulin levels decreased by 34% at the two levels of glucose infusion tested (P<0.05). Basal levels of C-peptide, insulin-like growth factor (IGF)-I and IGF-binding protein-3 increased almost 2-fold, while levels of glucose, insulin, glucagon, GH and IGF-binding protein-1 remained unchanged. Non-esterified fatty acid levels decreased (P<0.05). In addition, 24 h urinary nitrogen excretion decreased by 26% (P<0.01) after GH treatment, while skeletal muscle protein synthesis and 3-methylhistidine excretion in urine remained unchanged. Energy expenditure increased by 5% (P<0.05) after treatment, whereas fat and carbohydrate oxidation were unaltered. In conclusion, when glucose flux was normalized by compensatory hyperinsulinaemia under conditions of GH-induced insulin resistance, intracellular rates of oxidation of glucose and fat remained unchanged. The nitrogen retention accompanying GH treatment seems to be due largely to improved nitrogen balance in non-muscle tissue.

Over the last decades, surgical complication rates have fallen drastically. With the introduction of new surgical techniques coupled with specific evidence-based perioperative care protocols, patients today run half the risk of complications compared with traditional care. Many patients who in previous years needed weeks of hospital care now recover and can leave in days. These remarkable improvements are achieved by using nutritional stress-reducing care elements for the surgical patient that reduce metabolic stress and allow for the return of gut function. This new approach to nutritional care and how it is delivered as an integral part of enhancing recovery after surgery are outlined in this review. We also summarize the new and increased understanding of the effects of the routes of delivering nutrition and the role of the gut, as well as the current recommendations for artificial nutritional support. [ABSTRACT FROM AUTHOR]

This narrative review presents a biological rationale and evidence to describe how the preoperative condition of the patient contributes to postoperative morbidity. Any preoperative condition that prevents a patient from tolerating the physiological stress of surgery (e.g. poor cardiopulmonary reserve, sarcopaenia), impairs the stress response (e.g. malnutrition, frailty), and/or augments the catabolic response to stress (e.g. insulin resistance) is a risk factor for poor surgical outcomes. Prehabilitation interventions that include exercise, nutrition, and psychosocial components can be applied before surgery to strengthen physiological reserve and enhance functional capacity, which, in turn, supports recovery through attaining surgical resilience. Prehabilitation complements Enhanced Recovery After Surgery (ERAS) care to achieve optimal patient outcomes because recovery is not a passive process and it begins preoperatively. [ABSTRACT FROM AUTHOR]

Clinical outcome is negatively correlated to postoperative insulin resistance and hyperglycemia. The magnitude of insulin resistance can be modulated by glucose control, preoperative nutrition, adequate pain management and minimal invasive surgery. Effects of glucose control on perioperative glucose kinetics in liver surgery is less studied. 18 patients scheduled for open hepatectomy were studied per protocol in this prospective, randomized study. In the treatment group (n = 9), insulin was administered intravenously to keep arterial blood glucose between 6 and 8 mmol/l during surgery. The control group (n = 9) received insulin if blood glucose >11.5 mmol/l. Insulin sensitivity was measured by an insulin clamp on the day before surgery and immediately postoperatively. Glucose kinetics were assessed during the clamp and surgery. Mean intraoperative glucose was 7.0 mM (SD 0.7) vs 9.1 mM (SD 1.9) in the insulin and control group respectively (p < 0.001; ANOVA). Insulin sensitivity decreased in both groups but significantly (p = 0.03, ANOVA) more in the control group (M value: 4.6 (4.4–6.8) to 2.1 (1.2–2.6) and 4.6 (4.1–5.0) to 0.6 (0.1–1.8) mg/kg/min in the treatment and control group respectively). Endogenous glucose production (EGP) increased and glucose disposal (WGD) decreased significantly between the pre- and post-operative clamps in both groups, with no significant difference between the groups. Intraoperative kinetics demonstrated that glucose control decreased EGP (p = 0.02) while WGD remained unchanged (p = 0.67). Glucose control reduces postoperative insulin resistance in liver surgery. EGP increases and WGD is diminished immediately postoperatively. Insulin seems to modulate both reactions, but mostly the WGD is affected. Intraoperative EGP decreased while WGD remained unaltered. ANZCTR 12614000278639. [ABSTRACT FROM AUTHOR]

The article discusses the period of starvation within the context of the pathophysiological changes that accompany major surgery. Topics covered include ways of assessing the magnitude of the stress response, the use of minimally-invasive surgery to reduce the prolonged effects of starvation, and maltodextrin as the key composition of oral carbohydrate loading.

Summary: Background & aims: Whilst preoperative carbohydrate treatment (PCT) results in beneficial physiological effects, the effects on postoperative clinical outcomes remain unclear and were studied in this meta-analysis. Methods: Prospective studies that randomised adult non-diabetic patients to either PCT (≥50 g oral carbohydrates 2–4 h pre-anaesthesia) or control (fasted/placebo) were included. The primary outcome was length of hospital stay. Secondary outcomes included development of postoperative insulin resistance, complications, nausea and vomiting. Methodological quality was assessed using GRADEpro® software. Results: Twenty-one randomised studies of 1685 patients (733 PCT: 952 control) were included. No overall difference in length of stay was noted for analysis of all studies or subgroups of patients undergoing surgery with an expected hospital stay ≤2 days or orthopaedic procedures. However, patients undergoing major abdominal surgery following PCT had reduced length of stay [mean difference, 95% confidence interval: −1.08 (−1.87 to −0.29); I 2 = 60%, p = 0.007]. PCT reduced postoperative insulin resistance with no effects on in-hospital complications over control (risk ratio, 95% confidence interval, 0.88 (0.50–1.53), I 2 = 41%; p = 0.640). There was significant heterogeneity amongst studies and, therefore, quality of evidence was low to moderate. Conclusions: PCT may be associated with reduced length of stay in patients undergoing major abdominal surgery, however, the included studies were of low to moderate quality. [Copyright &y& Elsevier]

Enhanced recovery after surgery begins before the onset of surgery with detailed and structured preparation of the patient for the surgery they are about to go through. Detailed information to the patient and their kin at a separate occasion in advance of the admission is an important beginning. This ensures that the patient knows what they can do to enhance recovery and what to expect postoperatively including when to go home. Avoiding bowel preparation as a routine avoids unnecessary fasting and fluid derangements before the onset of surgery. Instead of the traditional overnight fasting routine that has no scientific support, modern fasting guidelines should be applied. In these, patients are recommended to take clear fluids ad libitum up until 2 hours before anesthesia. A further improved preparation can be achieved by having the patient take a carbohydrate-rich clear drink 2 hours before anesthesia. This changes the overnight fasted state of metabolism into a fed state, improves well-being perioperatively, and markedly reduces the metabolic derangement and the risk for hyperglycemia in the postoperative phase. [ABSTRACT FROM AUTHOR]

Fasting overnight has been the routine before elective surgery for the past century. Fasting guidelines in many countries have recently been modernized and it is now recommended that most patients drink clear fluids up until 2-3 h before anaesthesia. Several studies have shown that if the overnight fasted state is changed into a carbohydrate fed state before the onset of the operation, several further benefits can be gained. In particular, patients treated with carbohydrates at sufficient concentrations (12.5%) in a specially designed drink for preoperative use have less preoperative discomfort, and fewer metabolic derangements postoperatively. Of special interest is the finding that this treatment (or a 30% glucose infusion given at a fairly high rate) results in substantially less postoperative insulin resistance. This is important, since insulin resistance is the underlying mechanism behind hyperglycaemia, which has been shown to be detrimental in postoperative patients. Recent studies show that preoperative carbohydrates counteract the key disturbances that cause hyperglycaemia, primarily increased endogenous glucose production and reduced glucose uptake in peripheral tissues. This paper reviews the concept of preoperative carbohydrates as opposed to overnight fasting, the mechanisms of action and clinical outcomes for this treatment. [ABSTRACT FROM AUTHOR]

Studies the effects of preoperative oral carbohydrate treatment on postoperative changes in insulin resistance and substrate utilization in the absence of confounding factors. Circulating glucose and insulin concentrations during basal and clamp periods; Glucose oxidation rates during preoperative basal period and after insulin infusion.