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N Mertes

Publications and source records attributed to N Mertes.

At least 19 recordsLinked to original sources
PubMed2000

Intra-articular clonidine analgesia after knee arthroscopy.

Recently, it was suggested that peripherally-mediated analgesia can be accomplished by the intra-articular delivery of the mu-opioid morphine or of the a2-agonist clonidine. This clinical study assesses the potential peripheral analgesic effect of the combination of morphine and clonidine after intra-articular administration. Sixty patients (American Society of Anesthesiologists status I or II) undergoing arthroscopic repair of the knee during general anaesthesia were randomized to receive after operation, in a double-blind manner, either 1 mg morphine intra-articularly (group 1); 150 microg clonidine intra-articularly (group 2); or 1 mg morphine + 150 microg clonidine intra-articularly (group 3); or normal saline intra-articularly (group 4) in a volume of 30 mL, respectively. Visual analogue pain scores (VAS), duration of analgesia as defined by first demand for supplemental analgesics, subsequent 24 h consumption of postoperative supplementary analgesics, and patient satisfaction were evaluated. Co-administration of morphine + clonidine (group 3) resulted in a significant VAS reduction at 2 h after injection compared with the other groups. There was a tendency towards a lower need for supplementary rescue analgesia and towards a more prolonged analgesia in group 3 (211 min +/- 224 min SD) compared with group 1 (173 min +/- 197 min SD) and group 4 (91 min +/- 21 min SD). More patients were very satisfied with the postoperative analgesic regimen receiving the combination of morphine and clonidine (group 3) at 24 h postoperatively. Thus we conclude, that the peripheral co-delivery of an opioid and an a2-agonist will result in improved postoperative pain relief, when compared with each single agent given alone.

Adrenergic alpha-Agonists↗
PubMed2000

Acute pain management: analysis, implications and consequences after prospective experience with 6349 surgical patients.

An acute pain service (APS) was set up to improve pain management after operation. We attempted to reduce the length of stay in the intensive care unit (ICU) of patients undergoing major surgery and to improve their homeostasis and rehabilitation using a multimodal approach (pain relief, stress reduction, early extubation). Patient-controlled epidural analgesia (PCEA) was a keystone of this approach. If PCEA was not applicable, patients received patient-controlled intravenous analgesia (PCIA) instead. Brachial plexus blockade (BPB) was used for surgery of the upper limbs. A computer based documentation system was used to help evaluate prospectively (a) the quality of analgesia, (b) adverse effects and risks of the special pain management techniques, and (c) cost-effectiveness. Patients receiving PCEA (n = 5.602) received a patient-titrated continuous infusion into the epidural space of either bupivacaine 0.175% or ropivacaine 0.2%, with 1 microg sufentanil mL(-1) added, followed by patient-controlled boluses of 2 mL (lockout time 20 min). For patients receiving PCIA (n = 634) an initial bolus of 7.5-15 mg piritramide was given, and the subsequent bolus was 2 mg (lockout time 10 min). A continuous infusion of bupivacaine 0.25% was administered to patients receiving BPB (n = 113). The dose was titrated to a dynamic visual analogue scale (VAS) scores < 40. The mean treatment periods were: BPB = 4.33 days, PCEA = 5.6 days, PCIA = 5.0 days. In the case of PCEA, the quality of pain relief, vigilance and satisfaction were superior compared with the PCIA method, which resulted in greater sedation and nausea. Although personal supervision was higher for the PCEA-treated patients, cost analysis revealed final savings of Euro 91,620 for the year 1998 obviating the need for an ICU stay totalling 433 days. Provided that PCEA is part of a fast-track protocol employing early tracheal extubation and optimal perioperative management, the associated initial higher costs will be recouped by the benefits to patients of better pain relief after surgery and fewer days subsequently spent in the ITU.

Amides↗
PubMed2000

Cost containment through L-alanyl-L-glutamine supplemented total parenteral nutrition after major abdominal surgery: a prospective randomized double-blind controlled study.

BACKGROUND & AIMS: Glutamine is recognized as a conditionally essential amino acid. Recent studies indicate that glutamine-containing total parenteral nutrition improves nitrogen economy, enhances gastrointestinal and immune functions and shortens hospital stay. METHODS: Thirty-seven patients (19 w and 18 m; age 61. 4+/-10.4 years; BMI 23.7+/-2.8 kg/m(2)) following major abdominal surgery receiving an isonitrogenous isoenergetic TPN with or without alanyl-glutamine supplementation (0.5 g/kg BW/day), were evaluated in a double-blind, randomized, controlled trial over a five-day period by measuring nitrogen balance, selected biochemical parameters and length of hospital stay. RESULTS: Supplemental alanyl-glutamine improved the overall mean (-3.5+/-1.6 vs. -5.5+/-1. 4 g N;P<0.05) and cumulative nitrogen balance (-14.1+/-9.1 vs. -21.7+/-11.4 g N;P<0.05) compared with the isonitrogenous, isoenergetic standard regimen. Alanyl-glutamine normalized plasma glutamine concentration and reduced the length of hospital stay (12.8+/-2.6 vs. 17.5+/-6.4 days;P<0.05). CONCLUSIONS: The results of the study confirm that supplementation with synthetic alanyl-glutamine dipeptide is associated with cost containment due to shortened hospitalization and improved nitrogen economy.

Abdomen↗
PubMed2000

What concentration of sufentanil should be combined with ropivacaine 0.2% wt/vol for postoperative patient-controlled epidural analgesia?

UNLABELLED: In this randomized double-blinded study, we sought to determine an optimal dose-combination of sufentanil with ropivacaine 0.2% wt/vol as postoperative epidural analgesics. One hundred twenty patients undergoing major abdominal surgery under general and thoracic epidural anesthesia (T9-11) were assigned to groups receiving patient-controlled epidural analgesia with ropivacaine 0.2% wt/vol (R), ropivacaine 0.2% wt/vol + sufentanil 0.5 microg/mL (R+S0.5), 0. 75 microg/mL (R+S0.75), 1.0 microg/mL (R+S1). A visual analog score of less than 40 was considered effective, and all side effects were recorded. In randomized subgroups (10 patients per group), plasma pharmacokinetic data were obtained for both epidural drugs. Four patients in Group R and two in Group R+S0.5 were excluded because of inadequate analgesia. The drug infusion rates (range of means: 5.4-5. 9 mL/h) were similar in all patients. Analgesia was superior for sufentanil 0.75 microg/mL with no further enhancement by the larger sufentanil concentration of 1 microg/mL. Sufentanil plasma levels were within the range of the minimal effective concentrations (highest in R+S1), and there was no covariation between plasma levels and pain relief. Free ropivacaine plasma concentrations remained stable for 96 h. No severe side effects were detected, although pruritus correlated with an increasing dose of sufentanil. We conclude that the combination of ropivacaine 0.2% wt/vol and 0.75 microg/mL sufentanil provided the best analgesia with the fewest side effects of the three combinations tested. IMPLICATIONS: Sufentanil is added to epidural infusions of ropivacaine 0.2% wt/vol to improve the effectiveness of postoperative pain management. Regarding the risk of side effects, however, it is still unclear what concentration of sufentanil should be added to the local anesthetic. For postoperative thoracic epidural analgesia after major abdominal surgery, the combination of ropivacaine 0.2% wt/vol and 0.75 microg/mL sufentanil resulted in an appropriate cost:benefit ratio between good analgesia and side effects.

Adult↗
PubMed1999

Epidural analgesia with local anesthetics after abdominal surgery: earlier motor recovery with 0.2% ropivacaine than 0.175% bupivacaine.

UNLABELLED: The aim of this prospective, randomized, double-blinded study was to compare pain relief, side effects, and ability to ambulate during epidural anesthesia with ropivacaine 0.2% plus sufentanil versus bupivacaine 0.175% plus sufentanil after major gastrointestinal surgery. Epidural catheters were inserted at T8-11, and 30 microg of sufentanil with 15 mL of ropivacaine 0.75% (Group 1, n = 42) or bupivacaine 0.5% (Group 2, n = 44) was injected. General anesthesia was induced, a continuous epidural infusion (5 mL/h) was then begun with 1 microg/mL sufentanil plus ropivacaine 0.2% (Group 1) or bupivacaine 0.175% (Group 2). Postoperatively, the infusion rate was adjusted to individual requirements. Patients were also able to receive additional 2-mL bolus doses every 20 min. Demographic data (except for gender and height), analgesia, drug dosage, and side-effects, including motor blockade (Bromage score), were similar in both groups, but mobilization recovered more quickly in Group 1. Gender, age, ASA physical status, duration of surgery, and intraoperative blood loss had no effect on mobilization. We conclude that epidural analgesia is effective and safe with both regimens. There is not necessarily a correlation between the Bromage score and the desired outcome of mobilization. The ability to walk postoperatively is hastened if ropivacaine is used instead of bupivacaine. IMPLICATIONS: Regarding pain relief and side effects, epidural analgesia with ropivacaine 0.2% and sufentanil 1 microg/mL yields pain scores and pain intensity comparable to those for the well evaluated combination of bupivacaine 0.175% and sufentanil 1 microg/mL. However, earlier recovery of the ability to walk unassisted in patients receiving the combination of ropivacaine and sufentanil may result in their earlier rehabilitation.

Abdomen↗
PubMed1998

A multimodal approach to control postoperative pathophysiology and rehabilitation in patients undergoing abdominothoracic esophagectomy.

UNLABELLED: This two-armed study was designed to determine whether recovery after esophageal resection may be improved by introducing a new multimodal approach. For 8 mo after the new approach was introduced, all patients undergoing abdominothoracic esophageal resection were studied (Group 2; n = 42). For comparison, a retrospective analysis was also conducted using the data of all patients who had undergone this operation in the 8 mo before the introduction of the new regimen, when the traditional therapy was still in use (Group 1; n = 49). All patients received an epidural catheter at the level of T6-9 before the induction of general analgesia. Afterward, Group 1 patients were operated under general anesthesia. For postoperative pain relief, a mixture of bupivacaine 1.25 mg/mL and sufentanil 1 microg/mL was administered during 5 days without titration of the quality of analgesia. Patients in Group 2 received a preoperative bolus of 10-15 mL bupivacaine 2.5 mg/mL and 20-30 microg sufentanil. After sensory block up to T4 was confirmed, general anesthesia was introduced and intraoperatively combined with a continuous infusion of 5 mL/h of a solution containing bupivacaine 1.75 mg/mL and sufentanil 1 microg/mL. Postoperatively, the epidural infusion rate was adjusted to the need of the individual patients, who were able to administer themselves additional bolus doses of 2 mL with a lockout time of 20 min. Early tracheal extubation and forced mobilization were pursued to improve recovery. Demographic data of both groups were comparable. The pain relief of Group 2 patients was superior to that of patients in Group 1. The nitrogen balance of a subgroup of nine matched pairs of patients with comparable nutritional status was less negative in Group 2 patients on Postoperative Days 1 and 2. Patients in Group 2 were tracheally extubated earlier (mean 6.7 vs 25.1 h after admission to the intensive care unit [ICU]), mobilized earlier (mean 1.2 vs 2.0 days after surgery), discharged from the ICU earlier (mean 1.7 vs 4.0 days), and fulfilled criteria for discharge from the ICU (mean 1.8 vs 4.1 days) and from the intermediate care unit earlier (4.9 vs 6.4 days). We conclude that the multimodal approach may improve recovery and thus reduce costs after abdominothoracic esophageal resection. IMPLICATIONS: Analgesia and blockade of the perioperative stress response, combined with other aspects of postoperative therapy, may improve recovery after surgery. The intensive care unit stay after esophageal resection was reduced by a new regimen (thoracic epidural analgesia, early tracheal extubation, forced mobilization). This approach may influence the cost of major surgery.

Abdomen↗
PubMed1997

Strategies to reduce the need for peri-operative blood transfusion.

Therapeutic regimens involving the transfusion of blood components are a matter of debate, not only with regard to patients' safety, but also with regard to cost-effectiveness. The following different measures to reduce the use of blood components and their efficacy are discussed: autologous transfusion, including predonation, isovolaemic haemodilution and peri-operative retransfusion; toleration of a lower haematocrit; and measures to reduce blood loss. In particular, a combination of these methods may be most effective at reducing transfusion needs.

Blood Loss, Surgical↗
PubMed1997

IgE-mediated hypersensitivity to latex in childhood.

A total of 267 children scheduled to receive anesthesia during a surgical, neurosurgical, or orthopedic intervention were investigated. IgE antibodies against latex were detected in serum samples of 6.4% (17/267 children) of the patients. The most important difference between sensitized and nonsensitized children was the number of surgical interventions in the past. The median of surgical interventions was 1.0 in the nonsensitized group of children and 3.0 in the sensitized group. Only 0.9% of the children with up to two surgical interventions and 34.1% with three or more procedures were sensitized to latex. Only one of the sensitized children developed intraoperative anaphylaxis during intervention after our investigation. We conclude that children with a history of three or more surgical interventions have a high risk of sensitization to latex proteins. Nevertheless, the predictive value of IgE antibodies against latex for development of anaphylaxis during anesthesia seems to be low.

Adolescent↗
PubMed1996

Postoperative alpha 2-adrenergic stimulation attenuates protein catabolism.

The metabolic effects of continuous intravenous (IV) application of the alpha 2 agonist clonidine were evaluated by assessment of nitrogen economy and postaggression endocrine patterns. Twenty-four patients undergoing abdominothoracic esophageal cancer resection were studied. Thirteen of these patients with alcohol abuse were treated postoperatively with IV clonidine for prevention of alcohol withdrawal syndrome. Eleven patients who were not treated with clonidine served as controls. All patients were treated in a standardized manner in regard to surgical technique, balanced anesthesia, and postoperative intensive care treatment, including thoracic epidural analgesia with bupivacaine and fentanyl. Isonitrogenous and isocaloric nutrition was comparable in all patients. A significantly improved cumulated 6-day nitrogen balance was found in clonidine-treated patients (-1.5 +/- 4.9 g nitrogen) compared to the control group (-17.6 +/- 4.2 g nitrogen) (P < 0.05). The main reason for improved nitrogen economy may be clonidine-induced growth hormone (GH) release. The pattern of insulin-like growth factor I (IGF-I) and insulin-like growth factor binding protein 3 (IGFBP-3) concentrations could support this hypothesis.

Adrenergic alpha-Agonists↗
PubMed1996

A new method for continuous intramucosal PCO2 measurement in the gastrointestinal tract.

Gastric tonometry has been introduced for the early detection of impaired splanchnic perfusion by determination of the intramucosal PCO2. However, due to methodological problems, i.e., instability of CO2 in water, to assess the exact intramucosal PCO2 with the nasogastric tonometer is unreliable. The present in vitro and in vivo study examines a new fiberoptic PCO2 sensor for the continuous determination of the intramucosal PCO2 and compares these data with that of conventional tonometry. In an in vitro experiment the fiberoptic PCO2 sensor was used to determine the PCO2 of water and humidified air with predefined CO2 values. In both media, predefined CO2 values (35, 42, 49 mm Hg) could be assessed exactly after 9 min of equilibration with a maximum deviation less than 3.5%. In contrast, the values obtained by conventional tonometry showed larger differences. In in vivo experiments on six pigs PCO2 differences were induced by ventilatory changes to validate the fiberoptic PCO2 sensor. Under anesthesia a laparotomy was performed, the ileum punctured, and the fiberoptic PCO2 sensor introduced into the ileal lumen. Arterial PCO2 (PaCO2), mesenteric venous PCO2 (PmvCO2), and intramucosal PCO2, (PiCO2) were determined during normoventilation, hypoventilation, and hyperventilation. During hypoventilation the PiCO2 increased from 53.8 +/- 2.0 mm Hg (PaCO2 = 39.8 +/- 1.4 mm Hg, PmvCO2 = 48.7 +/- 2.7 mm Hg) to 66.5 +/- 4.9 mm Hg (PaCO2 = 52.7 +/- 3.1 mm Hg, PmvCO2 = 62.4 +/- 5.7 mm Hg). With hyperventilation the PiCO2 decreased to 46.8 +/- 2.5 mm Hg (PaCO2 = 29.8 +/- 1.8 mm Hg, PmvCO2 = 41.8 +/- 2.7 mm Hg). The coefficient of correlation (r2) between PiCO2 and PaCO2 was 0.82, and between PiCO2 and PmvCO2 0.94. The fiberoptic PCO2 sensor can determine PiCO2 in a precise and reliable manner, and can continuously record fast intraluminar changes of CO2 in the ileum that were caused by ventilatory changes. The fiberoptic PCO2 sensor is the only method that reliably monitors PiCO2 in the gastrointestinal tract. By the direct measurement of PCO2 the methodological problems associated with the conventional nasogastric tonometry are abolished.

Animals↗
PubMed1996

Gastric tonometry: precision and reliability are improved by a phosphate buffered solution.

OBJECTIVE: To compare a phosphate buffered solution with normal saline as tonometric fluid in intramucosal PCO2 measurement in humans. DESIGN: Prospective, unblinded comparison. SETTING: Postsurgical critical care unit of a university hospital. PATIENTS: Six septic patients. INTERVENTIONS: Two tonometric probes were positioned in the gastric lumen in each patient. One tube was used for conventional tonometry (saline-filled balloon), while phosphate buffered solution was instilled into the second tube. MEASUREMENTS AND MAIN RESULTS: PCO2 was determined with three blood gas analyzers (ABL 2 [Radiometer, Copenhagen, Denmark], Corning 288 [Ciba Corning Diagnostics GmbH, Neuss, Germany], and StatProfile 9 Plus [Nova Biomedical, Waltham, MA]). Eight parallel PCO2 measurements per patient were evaluated, yielding a total of 48 measurements with each tonometric solution. Intrainstrumental comparison of the PCO2 determinations demonstrated an increase of 12.3 +/- 9.9% for ABL 2, 3.10 +/- 12.9% for Ciba Corning 288, and 101.2 +/- 31.5% for StatProfile 9 Plus with the phosphate buffered solution. The PCO2 values were decreased by the following amounts when the three instruments were compared, using the saline method: 14.2 +/- 8.2% (Ciba Corning 288 vs. ABL 2); 40.7 +/- 9.9% (StatProfile 9 Plus vs. ABL 2); and 30.9 +/- 9.35% (StatProfile 9 Plus vs. Ciba Corning 288). The difference in PCO2 determination, resulting from the different instrument designs, were significant between the three blood gas analyzers (p<.001). In addition, the variance of the intramucosal PCO2 values was significant between blood gas analyzers (p<.001) with normal saline as tonometric solution, but not with phosphate buffered solution. The coefficients of determination between PCO2 values in saline and phosphate buffered solution were r2=.85 for ABL 2, r2=.81 for Ciba Corning 288, and r2=.74 for StatProfile 9 Plus. When all 48 PCO2 values were analyzed, the interinstrumental coefficients of determination within a method for saline (and for phosphate buffered solution in parenthesis) were:r2=.83 (.92) between ABL 2 and Ciba Corning 288, r2=.72 (.92) between ABL 2 and StatProfile 9 Plus, and r2=.81 (.98) between Ciba Corning 288 and StatProfile 9 Plus. CONCLUSIONS: A considerable instrumental bias in PCO2 analysis is observed when saline is used as tonometric fluid in gastric tonometry, thus preventing a reliable determination of intramucosal pH. The present in vivo data show that the accuracy and reliability of intramucosal pH measurement can be improved by the use of phosphate buffered solution as tonometric fluid.

Adult↗
PubMed1995

Repeated administration of recombinant human insulin-like growth factor-I in patients after gastric surgery. Effect on metabolic and hormonal patterns.

OBJECTIVE: The primary objective of this investigation was to evaluate the anticatabolic effects of repeated subcutaneous administration of recombinant human insulin-like growth factor-I (rhlGF-I) in patients after gastric surgery. SUMMARY BACKGROUND DATA: The anabolic and protein-sparing effects of growth hormone are primarily mediated by IGF-I. Malnutrition and catabolic states result in increasing blood levels of growth hormone and decreasing levels of IGF-I. Experimental data showed that exogenous IGF-I could attenuate or reverse catabolism. METHODS: After giving their written informed consent, 38 male and female patients undergoing gastrectomy (age 40-75 years, body mass index 17-30 kg/m2) were treated with 80 micrograms/kg body weight rhlGF-I or placebo in a prospective, randomized, double-blind study for 5 consecutive days. Patients received a standardized total parenteral nutritional regimen with 3 g/kg body weight glucose and 0.1 g/kg body weight nitrogen. Nitrogen balance and 3-methylhistidine excretion were measured daily. Hormone profiles (IGF-I, IGFBP1, IGFBP3, cortisol, insulin, glucagon, triiodothyronine [T3], levothyroxine [T4], and thyroxine-binding globulin) were taken.

Adult↗
PubMed1995

Improved PCO2 measurement in six standard blood gas analysers using a phosphate-buffered solution for gastric tonometry.

The measurement of gastric intramucosal pH serves as a non-invasive technique for early detection of gastrointestinal ischaemia in critically ill patients. The method is based on the determination of the partial pressure of carbon dioxide in a 0.9% saline solution using a standard blood gas analyser. However, the use of standard blood gas analysers leads to an underestimation of carbon dioxide partial pressure in saline. Instrumental biases of six blood gas analysers were investigated using either a saline or a phosphate-buffered solution. Both test solutions were equilibrated with five defined carbon dioxide concentrations. Each blood gas analyser underestimated this defined partial pressure of carbon dioxide with a bias between -3.7% and -57.5% if saline was used. The phosphate-buffered solution considerably improved instrumental precision, resulting in biases between +2.7% and -17.6% Thus, a phosphate-buffered solution increases the accuracy of gastric intramucosal pH measurement.

Blood Gas Analysis↗
PubMed1994

[Glucose-xylitol 35% (1:1) versus glucose 40%. Effectiveness and metabolic effects after major surgery].

Injury and stress are accompanied by a characteristic hormonal response and altered energy utilisation. Hyperglycaemia and negative nitrogen (N) balance are the leading symptoms of the metabolic changes in the post-operative state. In a prospective, randomised study the efficacy and metabolic effects of glucose-xylitol (GX) 35% (1:1) versus glucose (G) 40% were investigated in patients undergoing major surgery. METHOD. Twenty-four patients undergoing abdomino-thoracic oesophageal cancer surgery were treated in a standardised manner. Total parenteral nutrition was administered over 6 days (kg body wt.-1/day): day of surgery 1-1.25 g carbohydrate (CH); 1st postoperative day (POD) 1.5 g CH, 1 g amino acids (AA); 2nd POD 3 g CH, 1.5 g AA, 1.0 g fat; from 3rd POD 3 g CH, 1.5 g AA, 1.5 g fat (CH GX35% (n = 12) or G40% (n = 12), AA Intrafusin 15%, fat Intralipid 20%). Daily and cumulative N balances, blood-G profiles, blood chemistry, and physical parameters were determined. Glucagon and insulin profiles, CH losses, and oxalic acid secretion were measured. RESULTS. Both groups were comparable for age, body mass index, clinical and physical parameters, and blood chemistry. Mean cumulative N balances after 6 days were -12.0 +/- 16.3 g N for GX35% and -5.6 +/- 19.4 g N for G40% (n.s.; Wilcoxon, P < 0.05). Blood G was similar for both groups with values ranging from 130 to 240 mg/dl on the day of surgery and below 150 mg/dl on the consecutive days. In each group 1 patient needed additional insulin therapy. Glucagon and insulin levels did not show a significant difference between the groups. CONCLUSION. No difference in tolerance and efficacy of nutritional support by GX versus G at a dose of 3 g.kg body wt.-1.d in oesophagectomised patients could be observed. Similar blood G profiles were in accordance with comparable glucagon and insulin levels. Because of the high standard deviations of N balances, differences in efficacy could not be proven. A significantly lower level of pseudocholinesterase (PCHE) for G40% on day 7 might indicate enhanced hepatic protein synthesis in the GX group.

Adult↗
PubMed1994

[Safety and tolerance of a new dipeptide-containing amino acid solution DP-Gln 20 versus a conventional amino acid solution Vamin 18EF in patients after elective colon surgery].

OBJECTIVE AND METHODS: Recent studies have demonstrated the important role of glutamine in postoperative metabolism. Using dipeptide-containing amino acid solutions it is possible to enhance glutamine supply. Safety and tolerance of DP-Gln 20 (gly-gln, gly-tyr) and Vamin 18EF were investigated in an open, prospective, randomised study. 16 patients received isonitrogenous parenteral nutrition over 4 days. RESULTS: There was no difference in clinical and biochemical patterns between both groups. Complications and adverse events due to the infused amino acid solutions were not observed.

Adolescent↗