Intraoperative epidural blockade prevents the increase in protein breakdown after abdominal surgery

The effects of elective abdominal surgery on protein turnover: A meta-analysis of stable isotope techniques to investigate postoperative catabolism

BACKGROUND & AIMS

Elective surgery induces skeletal muscle wasting driven by an imbalance between muscle protein synthesis and breakdown. From examination of diverse stable isotope tracer techniques, the dynamic processes driving this imbalance are unclear. This meta-analysis aimed to elucidate the mechanistic driver(s) of postoperative protein catabolism through stable isotope assessment of protein turnover before and after abdominal surgery.

METHODS

Meta-analysis was performed of randomized controlled trials and cohort studies in patients undergoing elective abdominal surgery that contained measurements of whole-body or skeletal muscle protein turnover using stable isotope tracer methodologies pre- and postoperatively. Postoperative changes in protein synthesis and breakdown were assessed through subgroup analysis of tracer methodology and perioperative care.

RESULTS

Surgery elicited no overall change in protein synthesis [standardized mean difference (SMD) -0.47, 95% confidence interval (CI): -1.32, 0.39, p = 0.25]. However, subgroup analysis revealed significant suppressions via direct-incorporation methodology [SMD -1.53, 95%CI: -2.89, -0.17, p = 0.03] within skeletal muscle. Changes of this nature were not present among arterio-venous [SMD 0.61, 95%CI: -1.48, 2.70, p = 0.58] or end-product [SMD -0.09, 95%CI: -0.81, 0.64, p = 0.82] whole-body measures. Surgery resulted in no overall change in protein breakdown [SMD 0.63, 95%CI: -0.06, 1.32, p = 0.07]. Yet, separation by tracer methodology illustrated significant increases in urinary end-products (urea/ammonia) [SMD 0.70, 95%CI: 0.38, 1.02, p < 0.001] that were not present among arterio-venous measures [SMD 0.67, 95%CI: -1.05, 2.38, p = 0.45].

CONCLUSIONS

Elective abdominal surgery elicits suppressions in skeletal muscle protein synthesis that are not reflected on a whole-body level. Lack of uniform changes across whole-body tracer techniques are likely due to contribution from tissues other than skeletal muscle.

Epidural local anaesthetics versus opioid-based analgesic regimens for postoperative gastrointestinal paralysis, vomiting and pain after abdominal surgery

BACKGROUND

Gastrointestinal paralysis, nausea and vomiting and pain are major clinical problems following abdominal surgery. Anaesthetic and analgesic techniques that reduce pain and postoperative nausea and vomiting (PONV), while preventing or reducing postoperative ileus, may reduce postoperative morbidity, duration of hospitalization and hospital costs. This review was first published in 2001 and was updated by new review authors in 2016.

OBJECTIVES

To compare effects of postoperative epidural analgesia with local anaesthetics versus postoperative systemic or epidural opioids in terms of return of gastrointestinal transit, postoperative pain control, postoperative vomiting, incidence of anastomotic leak, length of hospital stay and costs after abdominal surgery.

SEARCH METHODS

We identified trials by conducting computerized searches of the Cochrane Central Register of Controlled Trials (CENTRAL) (2014, Issue 12), MEDLINE (from 1950 to December 2014) and EMBASE (from 1974 to December 2014) and by checking the reference lists of trials retained. When we reran the search in February 2016, we added 16 potential new studies of interest to the list of 'Studies awaiting classification' and will incorporate these studies into formal review findings during the next review update.

SELECTION CRITERIA

We included parallel randomized controlled trials comparing effects of postoperative epidural local anaesthetic versus regimens based on systemic or epidural opioids.

DATA COLLECTION AND ANALYSIS

We rated the quality of studies by using the Cochrane 'Risk of bias' tool. Two review authors independently extracted data and judged the quality of evidence according to the GRADE (Grades of Recommendation, Assessment, Development and Evaluation Working Group) scale.

MAIN RESULTS

We included 128 trials with 8754 participants in the review, and 94 trials with 5846 participants in the analysis. Trials included in the review were funded as follows: charity (n = 19), departmental resources (n = 8), governmental sources (n = 15) and industry (in part or in total) (n = 15). The source of funding was not specified for the other studies.Results of 22 trials including 1138 participants show that an epidural containing a local anaesthetic will decrease the time required for return of gastrointestinal transit as measured by time to first flatus after an abdominal surgery (standardized mean difference (SMD) -1.28, 95% confidence interval (CI) -1.71 to -0.86; high quality of evidence; equivalent to 17.5 hours). The effect is proportionate to the concentration of local anaesthetic used. A total of 28 trials including 1559 participants reported a decrease in time to first faeces (stool) (SMD -0.67, 95% CI -0.86 to -0.47; low quality of evidence; equivalent to 22 hours). Thirty-five trials including 2731 participants found that pain on movement at 24 hours after surgery was also reduced (SMD -0.89, 95% CI -1.08 to -0.70; moderate quality of evidence; equivalent to 2.5 on scale from 0 to 10). From findings of 22 trials including 1154 participants we did not find a difference in the incidence of vomiting within 24 hours (risk ratio (RR) 0.84, 95% CI 0.57 to 1.23; low quality of evidence). From investigators in 17 trials including 848 participants we did not find a difference in the incidence of gastrointestinal anastomotic leak (RR 0.74, 95% CI 0.41 to 1.32; low quality of evidence). Researchers in 30 trials including 2598 participants noted that epidural analgesia reduced length of hospital stay for an open surgery (SMD -0.20, 95% CI -0.35 to -0.04; very low quality of evidence; equivalent to one day). Data on costs were very limited.

AUTHORS' CONCLUSIONS

An epidural containing a local anaesthetic, with or without the addition of an opioid, accelerates the return of gastrointestinal transit (high quality of evidence). An epidural containing a local anaesthetic with an opioid decreases pain after abdominal surgery (moderate quality of evidence). We did not find a difference in the incidence of vomiting or anastomotic leak (low quality of evidence). For open surgery, an epidural containing a local anaesthetic would reduce the length of hospital stay (very low quality of evidence).

Randomized clinical trial investigating the stress response from two different methods of analgesia after laparoscopic colorectal surgery

Background

One of the key elements of managed recovery is thought to be suppression of the neuroendocrine response using regional analgesics. This may be superfluous in laparoscopic colorectal surgery with small wounds. This trial assessed the effects of spinal analgesia versus intravenous patient-controlled analgesia (PCA) on neuroendocrine responses in that setting.

Methods

A randomized clinical trial was conducted with participation of patients undergoing laparoscopic colorectal surgery within a managed recovery programme. Consenting patients were allocated randomly to spinal analgesia or morphine PCA as primary postoperative analgesia. The primary outcome was interleukin (IL) 6 levels; secondary outcomes were levels of cortisol, glucose, insulin and other cytokines, pain scores, morphine use and length of hospital stay. Stress response analysis was conducted before operation, and 3, 6, 12, 24 and 48 h after surgery.

Results

Of 143 eligible patients, 133 were randomized and 120 completed the study. Baseline patient characteristics were similar in the two groups. There were no significant differences in median levels of insulin, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12, interferon γ, tumour necrosis factor α or vascular endothelial growth factor between the spinal analgesia and PCA groups at any time point. Three hours after surgery (but at no other time point) median (i.q.r.) levels of cortisol (468 (329–678) versus 701 (429–820) nmol/l; P = 0·004) and glucose (6·1 (5·4–7·5) versus 7·0 (6·0–7·7) mmol/l; P = 0·012) were lower in the spinal analgesia group than in the PCA group. Median (i.q.r.) levels of total intravenous morphine were lower in the spinal analgesia group (10·0 (3·3–15·8) versus 45·5 (34·0–60·5) mg; P &lt; 0·001).

Conclusion

Spinal analgesia reduced early neuroendocrine responses and overall parenteral morphine use. Registration number: NCT01128088 (http://www.clinicaltrials.gov).

Feasibility and safety of radical cystectomy under combined spinal and epidural anesthesia in octogenarian patients with ASA score ≥3: A case series

INTRODUCTION

This study evaluated the feasibility and safety of open radical cystectomy (RC) under combined regional anesthesia (CRA) in high-risk octogenarian patients.

METHODS

We retrospectively evaluated the medical records of high-risk, octogenarian bladder cancer patients submitted to open RC with CRA. Demographic and clinical data, intraoperative parameters and perioperative and postoperative complications were recorded using the Clavien-Dindo classification.

RESULTS

In total, 14 male and 4 female patients, with a median age of 82.5 years were enrolled. Ureterocutaneostomy was performed in 15 patients and Bricker ileal conduit in the remaining 3. Operative time ranged from 97 to 184 minutes. Five patients were transfused and no major intraoperative complications occurred. Postoperative complications 30 days later included ileus (Grade II) in 3 patients, surgical trauma infection in 1 patient (Grade II), respiratory infection in 2 patients (Grade III), and hydronephrosis with concurrent urinary tract infection in 3 patients (Grade III). No deaths occurred.

CONCLUSIONS

Our study showed that octogenarian, high-risk bladder cancer patients with indications for RC can safely undergo the surgical procedure under CRA, without apparent increase in major complications.

Preoperative insulin resistance and the impact of feeding on postoperative protein balance: a stable isotope study

CONTEXT

Major surgery induces a catabolic state resulting in a net loss of body protein.

OBJECTIVES

Our objective was to compare protein metabolism before and after surgery in nondiabetic patients with and without preoperative insulin resistance (IR). It was hypothesized that the anabolic response to feeding would be significantly impaired in those patients with preoperative insulin resistance.

DESIGN

A hyperinsulinemic-euglycemic clamp has been used to identify two groups of patients: IR and insulin sensitive (IS). A tracer kinetics technique has been used to evaluate the metabolic response to food intake in both groups.

SETTING

Patients undergoing cardiopulmonary bypass participated.

PATIENTS OR OTHER PARTICIPANTS

Ten IS patients and 10 IR patients were enrolled in the study.

INTERVENTION

After an overnight fasting, a 3-h infusion of a solution composed of 20% glucose and of amino acids at a rate of 0.67 and 0.44 kcal/kg · h, respectively, was started in each group. Phenylalanine kinetics were studied at the end of fasting and feeding.

MAIN OUTCOME MEASURE

Effect of feeding on protein balance before and after surgery was evaluated. Protein balance has been measured as the net difference of protein breakdown minus protein synthesis.

RESULTS

Protein balance increase after postoperative feeding was blunted only in the IR group. In contrast, in the IS group, the postoperative anabolic effect of feeding was the same as before surgery.

CONCLUSIONS

These findings propose a link between insulin resistance and protein metabolism. When non-IR patients are fed, a significant anabolic effect in the postoperative period is demonstrated. In contrast, IR patients are less able to use feeding for synthetic purposes.

Peri-operative management of ablative and reconstructive surgery for invasive bladder cancer in the elderly

INTRODUCTION AND OBJECTIVES

Radical cystectomy and urinary diversion for muscle invasive bladder cancer is a demanding surgical procedure usually followed by a variable period of inability. It might be even more delicate in the elderly. We describe our protocol of pre, intra, and post operative management aimed at minimising the impact of bladder cancer surgery.

MATERIALS AND METHODS

The patients were submitted to reduced pre-operative fasting (6-8 hours), no mechanical bowel preparation, and insertion of an epidural cannula. Intra-operative Intra-operatively the protocol included: combined anesthesia (general+epidural), controlled hypotension, correction of blood losses in excess of 10% of the estimated total blood volume, O2 supplementation and insertion of a je, junal cannula for nutrition. Post-operatively: early removal of naso-gastric tubing (2-6 hours), parenteral and enteral nutrition started ion POD1.

RESULTS

The feasibility study was conducted on 18 patients, 14 males and 4 women, median age 70 years (range 55 to 82). Six patients belonged to category ASA II, and 12 to ASA III-IV. The protocol was completed by 10 patients and no completed by 8. The only step of the protocol that was not completed was the enteral nutrition that caused symptoms of bowel distension. Among the patients who completed the protocol the return of peristalsis and of normal bowel function were observed on POD 1, and POD 2, respectively, whereas, the recovery required one day more in the remaining patients.

DISCUSSION

The protocol was feasible, and contributed to an accelerated recovery of intestinal function. Compliance to the protocol was independent from age. The study is ongoing for a more precise evaluation of the outcomes of the protocol.