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R Angster

Publications and source records attributed to R Angster.

10 recordsLinked to original sources
PubMed2005

[Postoperative pain management].

Although scientific interest in the field of pain research is unremitting and the understanding of acute pain mechanisms has eminently advanced, it is evident that clinical practice of postoperative pain management still has major deficits. Indeed, the use of regional analgesia via a catheter, e.g. epidural analgesia (EDA), or patient controlled intravenous analgesia (PCIA) has become very popular. These methods require special equipment, adequate nursing skills and professional expertise as well as the establishment of clinical procedures and an appropriate logistic setup. However, the majority of patients are not managed by EDA or PCIA and cannot be ignored due to lack of knowledge of the proper use of basic analgesic treatment. Therefore, it makes sense to establish a standardized step-concept of postoperative pain management with regular quality control integrated into a multimodal perioperative rehabilitation program.

Analgesia, Epidural↗
PubMed2004

[Quality management during postoperative pain therapy].

BACKGROUND: A main target of surgical treatment is to minimize postoperative pain. The aim of this study was to evaluate the benefit of quality management on postoperative pain and to improve pain therapy. METHODS: In a prospective study, postoperative pain was recorded in a total of 700 patients in a general and visceral surgical ward in 2000, 2001, and 2002. Pain was measured on a ten-point visual analogue scale (0 no pain, 10 most severe pain). RESULTS: Applying the principles of quality management (plan, do, check, act), we analyzed the reasons for high pain scores in detail. After study of the results in 2000, additional recommendations and guidelines for perioperative pain therapy were provided to all the physicians, and the mean visual analogue pain scores decreased by 15% in 2001 and more than 30% in 2002. At baseline, 12% of patients had pain above the threshold of 3 at rest and 5 in motion. These scores could be reduced to 6% and 3% in the two successive years, respectively. CONCLUSION: A simple pain management system in a general surgical ward led to considerable improvement in postoperative pain scores as assessed by visual analogue scale.

Adolescent↗
PubMed2002

[Effect of thoracic epidural analgesia on the early postoperative phase after interventions on the gastrointestinal tract].

INTRODUCTION: Thoracic epidural anesthesia is increasingly being used in visceral surgery as an adjuvant to general anesthesia and, in addition, as a postoperative method of thoracic epidural analgesia (TEA). This method interrupts specifically nociceptive reflexes, increases the blood supply by blocking sympathetic activation, improves pulmonary function, and has a beneficial effect on gastrointestinal (GI) motility. METHODS: A retrospective study was conducted on 175 patients with a primary GI carcinoma operated between January 1, 1999 and December 31, 1999; 78 operations were performed on the upper GI tract (UGI, gastrectomy), and 97 on the lower GI tract (LGI, anterior rectum resection). The postoperative course in patients with and without TEA was compared. For intraoperative and postoperative catheter analgesia, bupivacaine (intraoperative: 0.25%; postoperative: 0.125%) and fentanyl were used. General anesthesia was administered as balanced anesthesia. RESULTS: A total of 102 patients received combined anesthesia with TEA (UGI n = 61/LGI n = 41) and 73 patients were given general anesthesia with continuous postoperative, intravenous pain therapy or a patient-controlled analgesia (PCA) pump (UGI n = 17/LGI n = 56). There was no difference between the groups with and without TEA in terms of initial demographic details, such as age distribution, tumor stage or ASA classification. Under TEA, the length of stay in the intensive care unit (P < 0.01), the administration of antibiotics (P < 0.001), days without oral nutrition (p < 0.05) and the rate of anastomosis insufficiencies (P < 0.001) was significantly reduced after operations on the upper GI tract. After surgery on the lower GI tract, the use of TEA led to less frequent vomiting and earlier resumption of GI motility (P < 0.01). However, these positive effects did not have a significant beneficial impact on overall hospitalization. CONCLUSION: The combination of TEA and general anesthesia has been shown to offer advantages after operations on both the upper and the lower GI tract. The positive effects of the TEA in the postoperative period should be used for the early enteric nutrition and mobilization of patients.

Aged↗
PubMed1999

[Epidural abscess following a lumbar epidural catheter for mobilization of the knee].

We report on a case of a lumbar epidural abscess with staphylococcus aureus following a catheter epidural anaesthesia in a previously healthy and not immunosuppressed 34-year-old female. The indication for the epidural anaesthesia was mobilization of the right knee following arthrotomy due to chronic synovitis. On postoperative day 7 the patient experienced lumbar pain, headache and meningism. Magnetic resonance imaging revealed an epidural abscess at the height of the 3rd and 4th lumbar vertebrae. A right-sided intralaminar fenestration with debridement and drainage of the abscess was carried out immediately after confirmation of the diagnosis. The patient was discharged from hospital on postoperative day 21 without any neurological sequelae. This is another addition to the published cases of epidural abscess following a epidural technique. It underlines the need for a proper aseptic technique, to abandon frequent changes of bacterial filters, daily examination of the entry site of the catheter and strategies for close and continuous monitoring of patients following epidural anaesthesia.

Abscess↗
PubMed1992

Does etomidate cause haemolysis?

Etomidate is currently presented as a solution with propylene glycol as solvent. This organic solvent has an extremely high osmolality and is probably responsible for some of the side effects of this drug. In order to detect haemolysis, an indication for cell damage, we have measured serum haptoglobin concentrations in 12 healthy male volunteers after administration of etomidate 0.3 mg kg-1. Six subjects received etomidate in propylene glycol (EtoPG) with an osmolality of 4965 mosmol kg-1 and six received etomidate in lipid emulsion (EtoLip, 400 mosmol kg-1). Haptoglobin concentrations in the EtoPG group decreased by 44% and 43% from baseline values at 2 and 4 h after administration, respectively, and were significantly smaller than after administration of EtoLip. After 24 h, haptoglobin concentrations had not reached baseline values.

Adult↗
PubMed1992

[The action of S-(+)-ketamine on serum catecholamine and cortisol. A comparison with ketamine racemate].

The S(+)-isomer of ketamine has about twice the anaesthetic potency of the commercially available racemic mixture of ketamine. It is assumed that the known side-effects of ketamine are significantly reduced when administering half the usual dose with the same pharmacodynamic effect [17, 25]. The aim of the present study was to determine the haemodynamic effects, the catecholamine and cortisol plasma levels after administration of equally potent doses of S-(+)-Ketamine and racemic mixture of ketamine. In addition, the effect of premedication with i.v. midazolam was assessed. METHOD. After approval by the ethics committee and written informed consent, 30 healthy male volunteers were randomly allocated to three groups (n = 10). Group 1 received 2 mg/kg ketamine racemate, group 2 1 mg/kg S-(+)-Ketamine, and group 3 1 mg/kg S-(+)-Ketamine 5 min after i.v.-premedication with 0.1 mg/kg midazolam. Non-invasive blood pressure (BP) and heart rate (HR) were continuously recorded. Blood samples were drawn 7 min before, and 2, 4, 8, 16, 32, 64 and 128 min after drug administration. Plasma epinephrine and norepinephrine (NE) levels were determined by HPLC and cortisol plasma levels by RIA. Data were analysed with the Kruskal-Wallis test (P < or = 0.05) for differences between groups. RESULTS. HR and BP showed a significant rise after injection of racemate and isomer, without any significant differences between groups. This was also seen for norepinephrine and cortical plasma levels. Epinephrine levels, however, differed between groups, showing a significant rise after racemate compared to isomer. Premedication with midazolam, in contrast, blunted major haemodynamic and hormonal changes. DISCUSSION. The haemodynamic changes did not differ between the racemate and isomer group despite a reduced isomer dose. HR and BP rise were similar, although epinephrine levels were significantly lower after isomer than racemate. Hence we assume that the increase in the haemodynamic parameters were mainly caused by NE. Midazolam apparently prevented the centrally mediated sympathetic stimulation caused by ketamine and its isomers. Therefore, i.v. premedication with midazolam should be applied when racemate or isomer is used, especially in high-risk cardiac patients.

Adult↗
PubMed1992

[Ketamine racemate or S-(+)-ketamine and midazolam. The effect on vigilance, efficacy and subjective findings].

Ketamine is a racemic mixture containing equal amounts of optical isomers that have almost identical pharmacokinetic properties but different pharmacodynamic effects. The S-(+)-isomer of ketamine has about twice the anaesthetic and analgesic potency of the racemic ketamine preparation and is judged to induce less psychic emergence reactions and to be followed by a more rapid recovery of vigilance. The present study was designed to assess whether the S-(+)-isomer of ketamine is superior to the racemic mixture in cardiovascular characteristics, emergence reactions and cognitive functions, and whether side effects may be reduced or prevented by administration of midazolam prior to injection of S-(+)-ketamine. METHODS. Following ethics committee approval and informed consent, 30 volunteers were randomly allocated in this double-blind study to three groups of 10 each. Group 1 received 2 mg/kg bw racemic ketamine, group 2, 1 mg/kg bw S-(+)-ketamine and group 3, 1 mg/kg bw S-(+)-ketamine after premedication with 0.1 mg/kg midazolam i.v. Cardiovascular changes, state of vigilance, cognitive performance, subjective mood and acceptance of anaesthesia were assessed by means of haemodynamic routine monitoring, electroencephalography (EEG), psychometric tests and interview. RESULTS. The increases in mean arterial pressure and heart rate following the injection of racemic ketamine and S-(+)-ketamine were identical and the differences from baseline values significant after both. Premedication with midazolam ensured stable haemodynamics after injection of S-(+)-ketamine. EEG analysis displayed the characteristic changes well known from ketamine anaesthesia for both racemic and S-(+)-ketamine. The vigilosomnoscript showed an identical profile of vigilance up to 30 min after injection of both drugs. The vigilance status after 125 min was less impaired by S-(+)-ketamine than by racemic ketamine. Psychological assessment showed a prompter recovery of visual attentiveness and sensorimotor performance in the S-(+)-ketamine group. Subjective mood was judged by the volunteers to be significantly better after S-(+)-ketamine, and volunteers found S-(+)-ketamine to be more acceptable than racemic ketamine. The frequency of dreams was the same after both drugs. No unpleasant dreams were reported after S-(+)-ketamine, but one of the volunteers who received racemic ketamine had uncomfortable dreams. Midazolam prevented any unpleasant emergence sequelae. On the other hand, the cognitive performance could not be restored to the baseline values until at least 240 min after injection of S-(+)-ketamine, because of the sedative effects of midazolam. DISCUSSION. These results suggest that S-(+)-ketamine offers the advantages of faster recovery of cognitive performance, greater acceptance by the volunteers and identical depth of anaesthesia after injection of half the dose compared with racemic ketamine. The clinical use of S-(+)-ketamine therefore seems to be justified. Premedication with benzodiazepines, e.g. midazolam, is essential. The dose to be administered, however, should be carefully selected in order not to abolish the positive effect of S-(+)-ketamine on vigilance by the sedative effects of the benzodiazepine.

Adult↗
PubMed1991

[The neuromuscular blocking effects of ORG 9426].

ORG 9426 is a new non-depolarizing steroidal muscle relaxant with a short onset time and intermediate duration of action. Its ED90 ist estimated to be between 0.25 and 0.36 mg/kg. The present study investigated the onset time, duration of action and time to spontaneous recovery after 0.3 and 0.9 mg/kg ORG 9426, respectively (i.e. about single or triple ED90). METHODS. Following the consent of the ethics committee and informed patient consent, two groups of 18 patients (ASA I or II) were formed, each scheduled for general or ORL surgery. After premedication with lormetazepam, anesthesia was induced with midazolam (0.07 mg/kg) and etomidate (0.3 mg/kg) and maintained with N2O/O2 at a 65:35 ratio, enflurane (0.8-1.5%) and supplements of fentanyl as needed. The ulnar nerve was stimulated with supramaximal 2 Hz Train-of-four (TOF) every 20 s. Neuromuscular twitch response was registered with EMG. Muscle relaxation was achieved by administration of ORG 9426 0.3 (group 1) and 0.9 mg/kg (group 2), respectively. The following parameters were measured: onset time (time interval from injection to maximal or total block), T125/75 (time for T1 to reach 25% or 75% of control), TOF70 (time for TOF ratio to reach 70% of control), heart rate and blood pressure. RESULTS. (mean +/- SD). At a dosage of 0.3 mg/kg, the onset time was 3.1 +/- 0.8 min and the maximum blockade was 87 +/- 9%. A dosage of 0.9 mg/kg led to complete paralysis (100%) in all patients within 1.2 +/- 0.3 min. The time for recovery of T1 to 25 and 75% of baseline was 18 +/- 7 and 26 +/- 8 min in group 1, in group 2 46 +/- 11 and 53 +/- 17 min, respectively. TOF70 (i.e., time to adequate spontaneous recovery of neuromuscular function) was achieved after 30 +/- 10 and 63 +/- 14 min, respectively. CONCLUSIONS. At a dosage of 0.3 mg/kg, ORG 9426 has an onset time of about 3 min and a duration of activity of nearly half an hour. Its neuromuscular effects are similar to a single ED90 dose of vecuronium. In contrast to a previous study, we observed a much shorter onset time of 70 s following the administration of 0.9 mg/kg. The clinical duration of action and spontaneous recovery of neuromuscular function, however, were significantly prolonged to more than 1 h. The hemodynamic parameters showed only slight alterations.

Adult↗
PubMed1990

[The effect of propofol-ketamine anesthesia on hemodynamics and analgesia in comparison with propofol-fentanyl].

Propofol (Diprivan), a modern intravenous hypnotic, produces a reduction in both cardiac index (CI) and mean arterial pressure (MAP). Ketamine (Ketanest), a potent analgesic, in contrast, causes an increase in MAP and CI. The aim of the present study was to investigate whether the combination of propofol and ketamine can give better hemodynamic stability during the induction and maintenance of general anesthesia than propofol used with fentanyl, whose cardiodepressant actions may cumulate. METHODS. For induction of general anesthesia 10 patients (ASA I and II) each received 3-5 boluses of propofol (0.5 mg.kg-1 during 35 s until predetermined level of anesthesia was reached (stage D2/E0 according to [20]) followed by a continuous propofol infusion (0.120 mg.kg-1.min). Fentanyl 0.1 mg was administered to each patient in group A for induction of anesthesia and again if evident pain was present. In group B ketamine was given following a pharmacokinetic model based on computer-simulated calculation. After an initial bolus of 38 mg injected within 2 min further doses of 42 mg, 35 mg, 32 mg and 28 mg ketamine were administered over 30 min at a time. Signs of evident pain were treated by means of supplementary doses of 0.5 mg.kg-1. RESULTS. In both groups a moderate drop of MAP was observed after the induction of general anesthesia. Two patients in each group showed a distinct decrease in MAP (-32%). The heart rate dropped slightly (-9%) in group A, but did not change in group B. Following intubation the MAP rose by less in group A (+8%) than in group B (+21%). After the beginning of the operation the group treated with propofol/fentanyl showed major hemodynamic changes; in particular, bradycardia with less than 40 bpm was observed in more patients than in the propofol/ketamine group. Postoperatively, fewer patients in group B required rescue doses of analgesics (1 of 10) than these in group A (7 of 10), though vigilance was better in group B. DISCUSSION. The dose of ketamine administered during the induction of general anesthesia may have been not high enough to neutralize the cardiodepressant effect of propofol. But during the maintenance of anesthesia there was in fact better hemodynamic stability in group B than in group A as a result of the neutralization of opposing actions. Fentanyl even intensified the fall in MAP after propofol. Patients in group B showed better vigilance as well as better pain relief postoperatively. The population of the fentanyl group was obviously more deeply sedated and analgesia was still inadequate. In our study general intravenous anesthesia with propofol and ketamine offered the advantages of better analgesia, a higher state of vigilance and the absence of respiratory depression during the postoperative phase compared with the combination of propofol and fentanyl.

Analgesia↗