Biomedical subjects

Leopold Eberhart

Publications and source records attributed to Leopold Eberhart.

8 recordsLinked to original sources

PubMed2005

Effect of laparoscopic colon resection on postoperative glucose utilization and protein sparing: an integrated analysis of glucose and protein metabolism during the fasted and fed States using stable isotopes.

HYPOTHESIS: Using a stable isotope method to quantify postoperative changes in glucose and protein metabolism, patients undergoing laparoscopic-assisted colon resection and receiving 4 mg . kg(-1) . min(-1) of dextrose intravenously will (1) have more pronounced suppression of endogenous glucose production, leading to (2) a greater reduction in whole-body protein breakdown. DESIGN: Randomized protocol study. SETTING: Tertiary health care center in Montreal, Quebec. PATIENTS: Twelve patients scheduled for colonic resection were randomly allocated to undergo either laparoscopic (n = 6) or open (n = 6) surgery. INTERVENTIONS: Patients underwent a 6-hour stable isotope infusion study (3 hours fasted and 3 hours fed with dextrose infusion) on postoperative day 2. Whole-body protein breakdown and synthesis, amino acid oxidation, and endogenous glucose production and clearance were measured during the postabsorptive state using L-[1-(13)C]leucine and [6,6-(2)H(2)]glucose. Gas exchange and plasma concentrations of metabolites and hormones were also measured. MAIN OUTCOME MEASURES: Endogenous glucose production and whole-body protein breakdown during the fasted and fed states. RESULTS: In the fasted state, laparoscopy did not affect protein and glucose metabolism. Dextrose infusion suppressed endogenous glucose production in both groups, with the greatest extent in the laparoscopic group (P = .01). Higher respiratory quotients (P = .001) in the latter group also indicated increased exogenous glucose oxidation. Neither surgical approach nor nutrition affected aspects of protein metabolism. CONCLUSIONS: Laparoscopy for colon resection facilitates whole-body glucose uptake and utilization and oxidation of exogenous glucose with no protein-sparing effect. The laparoscopic approach modulates gluconeogenesis, although it is not sufficient in the presence of exogenous energy to promote nitrogen retention.

Carbon Isotopes↗

PubMed2005

Prospective application of a simplified risk score to prevent postoperative nausea and vomiting.

PURPOSE: To compare the risk-adapted approach with ondansetron against ondansetron plus dexamethasone to prevent postoperative nausea and vomiting (PONV) in a randomized clinical trial. METHODS: 460 patients scheduled for elective surgery were enrolled in this prospective study and stratified according to a simplified risk score for PONV. Patients having no or one risk factor were considered at low risk (group L) and did not receive study medication. Those with two to four risk factors were considered high risk and were randomized to receive 4 mg ondansetron plus placebo (group H-O) or 4 mg ondansetron plus 8 mg dexamethasone (group H-OD). Incidence and intensity of PONV were observed for 24 hr after surgery. Data were analyzed with Fisher's exact or Student's t tests; P < 0.05 was considered statistically significant. RESULTS: The incidence of PONV was 9% in group L (n = 87), 31% in those receiving ondansetron (group H-O, n = 185), and 22% in those receiving both drugs (group H-OD, n = 181). The incidence of PONV was significantly smaller in both high-risk groups than predicted without treatment (P < 0.001). While the incidence of PONV failed statistical significance between the two intervention groups (P = 0.08), the mean number of episodes of PONV and the mean maximal intensity of each episode of PONV were lower in group H-OD (P = 0.03 and P = 0.01, respectively). Patients of group H-OD required less antiemetic rescue therapy (P = 0.004). CONCLUSIONS: Ondansetron plus dexamethasone prevents PONV more effectively than ondansetron alone in patients at high risk for PONV.

Adult↗

PubMed2005

Differences in time to defibrillation and intubation between two different ventilation/compression ratios in simulated cardiac arrest.

OBJECTIVE: During basic life support (BLS) by a two-rescuer-team early defibrillation and ALS procedures should be performed without interruptions of the BLS-ventilation/compression sequence. The objective of this study was to determine the impact of a ventilation/compression ratio of 5:50 versus 2:15 on the time intervals "Start BLS to first shock" and "Start BLS to intubation". METHODS: Using a random cross over design 40 experienced paramedics performed a standard BLS/ALS-algorithm according to ILCOR guidelines in a manikin model with ventricular fibrillation (resusci skillreporter anne, Laerdal, Norway) performing both the 2:15 and the 5:50 ventilation/compression ratio. BLS was started with bag/valve/mask ventilation, a semi-automatic defibrillator (corpuls 08/16S) was connected with the manikin, ECG-analysis and three shocks were performed and the tracheal intubation was prepared. Ventilation/compression sequence was only interrupted during ECG-analysis and defibrillation. Expiratory volumes and number of compressions were measured. Variables were compared using paired Students t-test. In addition paramedics were interviewed about work-flow and emotional stress during the tests. RESULTS: The time interval "Start BLS to first shock" was 78 s (2:15-group) versus 63 s (5:50-group), p<0.0001, the time interval "Start BLS to intubation" was 183 s (2:15-group) versus 150 s (5:50-group), p<0.0001, mean ventilation volumes per minute were 4490 ml (2:15-group) versus 4370 ml (5:50-group), p>0.1, mean number of compressions were 65 min-1. (2:15-group) versus 68 min-1 (5:50-group), p>0.1. The work-flow and emotional stress was appraised by the paramedics to be significantly superior in the 5:50 ratio (p<0.0001). CONCLUSIONS: The ventilation/compression ratio of 5:50 compared with 2:15 during BLS with an unsecured airway reduces the time until the first defibrillation and tracheal intubation was performed without changes in ventilation volume and compressions per minute. The Paramedics stated that the 5:50 ratio improved the work-flow and reduced the emotional stress.

Allied Health Personnel↗

PubMed2005

Type 2 diabetes mellitus and the catabolic response to surgery.

BACKGROUND: The authors tested the hypothesis that the catabolic responses to colorectal surgery are amplified in the presence of type 2 diabetes mellitus. METHODS: Seven nondiabetic and seven diabetic patients underwent a 6-h stable isotope infusion study (3 h fasted, 3-h glucose infusion at 4 mg . kg . min) on the second postoperative day. Leucine rate of appearance (Ra), leucine oxidation, nonoxidative leucine disposal, and glucose Ra were assessed by L-[1-C]leucine and [6,6-H2]glucose. Circulating concentrations of glucose, lactate, insulin, glucagon, and cortisol also were determined. RESULTS: Diabetic patients had a higher leucine oxidation than nondiabetic patients (P = 0.0003), whereas leucine Ra and nonoxidative leucine disposal were not different. Administration of glucose did not affect leucine kinetics regardless of whether patients were diabetic. In diabetic patients, glucose Ra was greater than in the nondiabetic group (P = 0.0032). Glucose infusion suppressed the endogenous glucose Ra to a lesser extent in diabetic than in nondiabetic patients (P = 0.0048). Plasma glucose concentrations were higher in diabetic than in nondiabetic patients (P = 0.0203), both in the postabsorptive and the fed state. Circulating concentrations of glucagon were higher (P = 0.0065) and concentrations of insulin were lower (P = 0.0146) in the presence of diabetes, resulting in a lower insulin/glucagon ratio (P = 0.0002). In diabetic patients, the insulin/glucagon ratio increased during glucose infusion to a lesser extent than in the nondiabetic group (P = 0.0014). CONCLUSION: Protein catabolism after colorectal surgery is increased in patients with type 2 diabetes mellitus as reflected by an increased oxidative protein loss.

Adult↗

PubMed2004

Epidural ropivacaine versus epidural morphine and the catabolic response to colonic surgery: stable isotope kinetic studies in the fasted state and during infusion of glucose.

BACKGROUND: The authors examined the hypothesis that epidural administration of local anesthetic, in contrast to epidural analgesia with morphine, inhibits postoperative protein oxidation during administration of glucose. METHODS: Fourteen patients were randomly assigned to undergo a 6-h stable isotope infusion study (3 h fasted, 3 h feeding with 4 mg.kg(-1).min(-1) glucose) on the second day after colorectal surgery using epidural analgesia with either continuous ropivacaine or intermittent morphine. Protein synthesis, breakdown and oxidation, and glucose production were measured by L-[L-13C]leucine and [6,6-2H2]glucose. Substrate oxidation rates were determined by indirect calorimetry. Plasma concentrations of metabolic substrates and hormones were also measured. RESULTS: Whole body protein breakdown, oxidation, synthesis, and glucose production in the fasted state were similar between the two groups. Glucose administration decreased protein breakdown (P = 0.01), protein synthesis (P = 0.001), and glucose production (P = 0.001) to the same extent in both groups, whereas protein oxidation was not significantly affected. The type of epidural analgesia did not significantly influence the circulating concentrations of metabolic substrates and hormones in the fasted or in the fed state. Carbohydrate oxidation rate in the ropivacaine group was greater than in patients receiving morphine (P = 0.04), regardless of whether glucose was infused. CONCLUSION: Epidural analgesia achieved with ropivacaine or morphine does not suppress the catabolic response to surgery, either under fasting conditions or in the presence of an energy supply.

Adult↗

PubMed2004

Postoperative protein sparing with epidural analgesia and hypocaloric dextrose.

OBJECTIVE: We examined the hypothesis that epidural analgesia prevents the increase in amino acid oxidation after elective colorectal surgery in patients receiving hypocaloric infusion of dextrose. SUMMARY BACKGROUND DATA: Increased oxidative protein loss after surgery may adversely affect postoperative outcome. We have previously shown that effective segmental pain relief by epidural analgesia improves postoperative substrate utilization, resulting in less protein catabolism. METHODS: We randomly allocated 10 patients to receive general anesthesia combined with epidural analgesia using bupivacaine/fentanyl and 10 to receive general anesthesia followed by patient-controlled analgesia with intravenous morphine. All patients received a peripheral 72-hour infusion of dextrose 10% from the day before until the second day after surgery. The dextrose infusion rate was adjusted to provide 50% of the patients' resting energy expenditure. The primary end point was whole-body leucine oxidation as determined by a stable isotope tracer technique (l-[1-C]leucine). RESULTS: In the intravenous analgesia group, leucine oxidation increased from 19 +/- 4 to 28 +/- 6 micromol kg h after surgery. Epidural analgesia prevented this increase of leucine oxidation (preoperative 21 +/- 6 micromol kg h, postoperative 21 +/- 5 micromol kg h). This difference was statistically significant (P = 0.01; analysis of variance for repeated measures). CONCLUSION: Perioperative epidural analgesia and hypocaloric dextrose infusion suppress the postoperative increase in amino acid oxidation, thereby saving more than 100 g of lean body mass per day.

Aged↗

PubMed2004

Cost analyses of remifentanil, mivacurium and ropivacaine - a systematic review.

Remifentanil, mivacurium and ropivacaine are the latest innovations in clinical anaesthesia and have gained increasing importance in daily practise due to their unique pharmacodynamic and pharmacokinetic properties. However, drug acquisition costs for these agents are considerably higher in most countries than for comparable substances. This review provides a systematic, critical appraisal of pharmacoeconomic studies with remifentanil, mivacurium and ropivacaine, primarily based on prospective, randomised trials. Results from analyses using cost-minimising techniques stress the issue of the higher drug acquisition costs. However, studies using a more sophisticated method (e.g., cost-effectiveness analysis) indicate comparable costs or even financial advantage in favour of the newer investigative drugs remifentanil, mivacurium and ropivacaine.

Amides↗

PubMed2002

The anabolic effect of epidural blockade requires energy and substrate supply.

BACKGROUND: The authors examined the hypothesis that continuous thoracic epidural blockade with local anesthetic and opioid, in contrast to patient-controlled intravenous analgesia with morphine, stimulates postoperative whole body protein synthesis during combined provision of energy (4 mg x kg(-1) x min(-1) glucose) and amino acids (0.02 ml x kg(-1) x min(-1) Travasol 10%, equivalent to approximately 2.9 g x kg(-1) x day(-1)). METHODS: Sixteen patients were randomly assigned to undergo a 6-h stable isotope infusion study (3 h fasted, 3 h feeding) on the second day after colorectal surgery performed with or without perioperative epidural blockade. Protein synthesis, breakdown and oxidation, glucose production, and clearance were measured by L-[1-(13)C]leucine and [6,6-(2)H(2) ]glucose. RESULTS: Epidural blockade did not affect protein and glucose metabolism in the fasted state. Parenteral alimentation decreased endogenous protein breakdown and glucose production to the same extent in both groups. Administration of glucose and amino acids was associated with an increase in whole body protein synthesis that was modified by the type of analgesia, i.e., protein synthesis increased by 13% in the epidural group (from 93.3 +/- 16.6 to 104.5 +/- 11.1 micromol x kg(-1) x h(-1) ) and by 4% in the patient-controlled analgesia group (from 90.0 +/- 27.1 to 92.9 +/- 14.8 micromol x kg(-1) x h(-1);P = 0.054). CONCLUSIONS: Epidural blockade accentuates the stimulating effect of parenteral alimentation on whole body protein synthesis.

Algorithms↗