[Continuous intrathecal administration of medication. Special features in anaesthesiology and intensive care]. / Kontinuierliche intrathekale Medikamentenapplikation. Anästhesiologische und intensivmedizinische Besonderheiten.

In anaesthesiological and intensive care practice patients are increasingly being treated with implanted medication pumps. Basic knowledge on the special aspects of this form of therapy is therefore important. During the preanasthesiology visit, information on the pump, the intrathecal catheter, type and dosage of the medication as well as the next scheduled refilling must be collected and documented. Needle punctures near the pump and the catheter must be avoided. During intensive care treatment any possible interaction and overdosing or underdosing of the intrathecally administered medication must be considered. Information on the schedule and punctual organisation of refilling are important to avoid complications.

Anaesthesia for brachytherapy--51/2 yr of experience in 1622 procedures.

BACKGROUND: Brachytherapy presents the anaesthetist with unique problems. Information on anaesthesia for brachytherapy, however, is limited. The aim of this paper is to report on our experience involving a large number of brachytherapy procedures. METHODS: A retrospective analysis of records of 1622 anaesthetic procedures in 952 patients is presented. Records were analysed in respect of patient data, tumour localization, brachytherapy treatment and the type and duration of anaesthetic procedures. RESULTS: More than one-third of patients were at high risk (ASA III or IV) and 40% were more than 60 yr. Repetitive treatments were performed on half of the patients. Breast cancer was the most common indication. The average duration of anaesthesia for pelvic brachytherapy was more than 3 h, with a high degree of variability. Regional anaesthesia was used in 30% of all cases and was the predominant technique for pelvic brachytherapy. Spinal catheter techniques represented a high proportion of those receiving regional anaesthesia. Complications resulting from regional and general anaesthesia were minor and no serious incidents occurred. CONCLUSIONS: Based on a large number of procedures, this study gives an example of anaesthetic management in brachytherapy. A substantial minority of patients would be considered high risk for surgical intervention. Regional anaesthesia was the principal technique used when dealing with tumours of the lower body.

[CT-controlled percutaneous lumbar discectomy in therapy of radicular pain]. / CT-gesteuerte perkutane Nukleotomie mit dem Dissektor zur Therapie chronischer Rückenschmerzen mit radikulärer Ausstrahlung.

Percutaneous disc decompression using the Decompressor system is another treatment option for patients suffering from chronic discogenic leg pain. This is the first report on a patient undergoing this procedure under CT-control. A 49 year old man with radicular leg pain showed significant pain reduction after percutaneus decompression of a discal herniation at the L4/5 level. The new system enables qualitative and quantitative measures of the removed disc material. CT-control ensures exact positioning of the device.

[Use of the World Health Organization guidelines on cancer pain relief before referral to a specialized pain service]. / Einsatz der WHO-Leitlinien für die Tumorschmerztherapie vor Zuweisung in eine Schmerzklinik.

In 1986 the World Health Organization (WHO) released guidelines for cancer pain relief. Since then, several controlled studies on effectiveness and practicability of these guidelines have been published. Various authors described inadequate use of these guidelines. We analysed, whether the pain medication of 160 cancer patients referred to the anesthesiological pain clinic at the university hospital of Vienna corresponded to the WHO guidelines or not. Adequacy of pain treatment was assessed using the pain management index (PMI). Multiple criteria were chosen to assess the conformity of the treatment with the guidelines. Furthermore we studied the effect of a strict use of the WHO guidelines in these patients. The average pain intensity of the referred patients was 75 mm (VAS). Negative PMI scores, indicating inadequate pain therapy, were found in 39 % of cases. A violation of the rules was found in 38% of the therapy schedules. Pain medication was then modified by switching to fixed time intervals, escalation of the steps of the WHO ladder, increasing the dosage or treating neuropathic pain with adjuvant drugs. Two weeks later the average pain score of the patients was reduced to 27 mm (VAS). At that time 72% of the patients quoted an adequate reduction of pain. Inadequate knowledge or disregard of the WHO guidelines for cancer pain relief are common and result in unnecessary and prolonged suffering in these patients.

Comparison between bupivacaine 0.125% and ropivacaine 0.2% for epidural administration to outpatients with chronic low back pain.

BACKGROUND AND OBJECTIVE: Epidural blocks should provide good analgesia for the treatment of chronic low back pain without any motor block to allow active physiotherapy. Epidural ropivacaine is known to produce less motor block compared to bupivacaine at anaesthetic concentrations. This prospective, randomized double blind study compares the analgesic, motor block, and haemodynamic effects of single shot epidural injections of ropivacaine 0.2% 10 mL with bupivacaine 0.125% in outpatients suffering from chronic low back pain. METHODS: Forty patients were assigned to receive either ropivacaine 0.2% (n = 20) or bupivacaine 0.125% (n = 20) within a series of eight single shot epidural blocks. RESULTS: Thirty-six patients received either ropivacaine 0.2% (n = 18) or bupivacaine 0.125% (n = 18) within a series of eight single shot epidural blocks. Both groups showed no significant differences either in analgesia, or in motor blockade or haemodynamic changes. Thus ropivacaine 0.2% did not reduce the incidence of motor block (9.0% of patients with motor block Bromage scores 1, 2 or 3 in ropivacaine or bupivacaine). The combination of repeated epidural analgesia and physiotherapy reduced the median pain-scores (visual analogu scale, 0-10) from 7 (SD +/- 1.6) at the beginning of the study to 4.1 (SD +/- 1.7) at the end of the series. CONCLUSIONS: Both bupivacaine 0.125% and ropivacaine 0.29% appear suitable for epidural administration to outpatients with chronic low back pain attending for epidural analgesia associated with physiotherapy (physical therapy).

[Lung edema in scuba diving]. / Akutes Lungenödem bei einer Taucherin.

The management of a diving-related emergency is frequently a great challenge for an emergency physician without a special diving medicine training or experiences. Almost every physician knows something about the medical therapy of diving-related accidents which are combined with a barotrauma or a decompression sickness. But there are still some rare symptoms and organ affections of diving-related emergencies which are unknown in common. In consideration of the present case of an acute diving-related lung edema we discuss the different reasons and differential diagnosis of diving emergencies.

Comparison of different quantitative sensory testing methods during remifentanil infusion in volunteers.

BACKGROUND: The aim of this study was to compare thermal and current sensory testing stimuli with respect to opioid responsiveness. METHODS: Eighteen healthy volunteers were randomized in a placebo-controlled, double-blind crossover study to receive an infusion of remifentanil 0.08 micro g kg(-1) min(-1) or saline for 40 min. Test procedures included determination of pain perception thresholds (PPT) and pain tolerance thresholds (PTT) to heat, cold, and current at 5, 250 and 2000 Hz, at baseline and at the end of the infusion. RESULTS: Both current at 5 Hz (PPT 3.69 (SD 2.48) mA vs 2.01 (1.52) mA; PTT 6.42 (2.79) mA vs 3.63 (2.31) mA; P<0.001) and 250 Hz (PPT 4.31 (2.42) mA vs 2.89 (1.57) mA; PTT 7.08 (2.68) mA vs 4.81 (2.42) mA; P<0.001) and heat (PPT 47.4 (2.7) degrees C vs 45.2 (3) degrees C; PTT 51.1 (1.8) degrees C vs 49.7 (1.8) degrees C; P<0.05) detected a significant analgesic effect of remifentanil compared with placebo. No analgesic effect was shown on cold or current at 2000 Hz. The magnitude of responsiveness of current stimuli at 5 Hz and 250 Hz was superior to heat stimuli. CONCLUSION: Both current (5 and 250 Hz) and heat sensory testing detected a significant analgesic effect of a remifentanil infusion compared with saline. There was more response to current testing.

[Use of electrocardiographic placement control of central venous catheters in Austria]. / Zur Nutzung der elektrokardiographischen Lagekontrolle zentralvenöser Katheter in Osterreich.

After placement of a central venous catheter the correct position of the catheter tip has to be verified. The use of intravascular ECG tracing via a guide-wire or via the saline-filled lumen of the catheter enables immediate and safe control of the position. Only if complications (e.g. pneumothorax) are suspected, further clinical and radiological diagnostics are necessary. Up to now, no data on the routine clinical use of this method are available. In April 1998, a semi-structured questionnaire was sent to the 518 heads of anaesthesiological, surgical and medical departments in Austria (33% of the questionnaires were returned). The subclavian (56%) and internal jugular veins (35%) are most frequently used for catheter insertion in Austria. Verification of the catheter tip placement by ECG-guidance is used in only 8% of cases, while radiographs are performed in most cases. Uncertainty with respect to forensic consequences of using the ECG-guidance for control of the catheter tip placement and the possible necessity of an additional radiograph are the main problems seen by the heads of the departments. After placement of a central venous line, measures for the verification of the catheter tip and measures for the control of possible complications have to be considered separately. Intravascular ECG tracing is unable to detect complications. Concerning the verification of the catheter tip position many studies confirm the easy handling, relevance of results and cost savings for this method. Its use for the control and documentation of the tip location is considered a standard. In Austria the consequent use of the method would offer the chance for significant reductions of treatment costs.

Genetic damage in operating room personnel exposed to isoflurane and nitrous oxide.

OBJECTIVES: To evaluate genetic damage as the frequency of sister chromatid exchanges and micronuclei in lymphocytes of peripheral blood of operating room personnel exposed to waste anaesthetic gases. METHODS: Occupational exposure was measured with a direct reading instrument. Venous blood samples were drawn from 10 non-smokers working in the operating room and 10 non-smoking controls (matched by age, sex, and smoking habits). Lymphocytes were cultured separately over 72 hours for each assay with standard protocols. At the end of the culture time, the cells were harvested, stained, and coded for blind scoring. The exchanges of DNA material were evaluated by counting the number of sister chromatid exchanges in 30 metaphases per probe or by counting the frequency of micronuclei in 2000 binucleated cells. Also, the mitotic and proliferative indices were measured. RESULTS: The operating room personnel at the hospital were exposed to an 8 hour time weighted average of 12.8 ppm nitrous oxide and 5.3 ppm isoflurane. The mean (SD) frequency of sister chromatid exchanges was significantly higher (10.2 (1.9) v 7.4 (2.4)) in exposed workers than controls (p = 0.036) the proportion of micronuclei (micronuclei/500 binucleated cells) was also higher (8.7 (2.9) v 6.8 (2.5)), but was not significant (p = 0.10). CONCLUSION: Exposure even to trace concentrations of waste anaesthetic gases may cause dose-dependent genetic damage. Concerning the micronuclei test, no clastogenic potential could be detected after average chronic exposure to waste anaesthetic gas. However, an increased frequency of sister chromatid exchanges in human lymphocytes could be detected. Although the measured differences were low, they were comparable with smoking 11-20 cigarettes a day. Due to these findings, the increased proportion of micronuclei and rates of sister chromatid exchanges may be relevant long term and need further investigation.

Ropivacaine and bupivacaine for long-term epidural infusion in a small child.

Ropivacaine is assumed to be less toxic than bupivacaine but there are no reports concerning its long-term use in paediatric anaesthesia. We report the use of ropivacaine for long-term epidural anaesthesia in a 21-month-old girl. In two consecutive periods of 3 days each, 0.5% bupivacaine and 0.5% or 0.75% ropivacaine were administered to facilitate painful vaginal brachytherapy. The mean dose of bupivacaine increased from 1.05 to 1.32 mg kg-1 h-1 and that of ropivacaine increased from 1.40 to 3.86 mg kg-1 h-1. No toxic side effects were observed. We conclude that both epidural ropivacaine and bupivacaine were effective and safe during long-term epidural anaesthesia in this particular case. However, the doses were potentially toxic and should therefore be used with extreme caution.

[Pain therapy near the spinal marrow. Status survey in Germany and Austria]. / Rückenmarknahe Schmerztherapie. Statuserhebung in Deutschland und Osterreich.

OBJECTIVE: The objective of this survey was to investigate the current status of the epidural and intrathecal management in patients with chronic cancer and non-cancer pain in Germany and Austria. METHODS: In June 1997 a questionnaire was sent to 598 German and Austrian anaesthesiologists specialized in pain therapy. Questions concerning the use of medicaments for epidural and intrathecal treatment of chronic pain were asked. RESULTS: The response rate was 23%. The data show that 78% of the anaesthesiologists use epidural or intrathecal analgesia in the therapy of chronic pain. Local anaesthetics are used by 85% of these anaesthesiologists, followed by morphine (72%), clonidine (48%), buprenorphine (34%), baclofen (20%), fentanyl (13%) and sufentanil (10%). For most of the treatments local anaesthetics are used, again followed by opioids und clonidine. In the 137 answering pain clinics 79.821 epidural and intrathecal analgetic treatments are performed per year. DISCUSSION: Epidural and intrathecal pain therapy is frequently used in Germany and Austria, either as a complementary or alternative treatment to systemic pain therapy. Local anaesthetics followed by opioids are the most commonly used medicaments for this treatment. For some of the applied substances neurotoxicological data are lacking. The use of these substances has to be considered very carefully.

[Occupational exposure to inhalation anesthetics at the work-place of veterinary surgery]. / Berufliche Belastung durch Inhalationsanästhetika am Arbeitsplatz des Tierarztes.

In a prospective study we evaluated the work-place pollution by isoflurane and nitrous oxide during various anaesthetic procedures in animal surgery. The study was conducted during one working week at an University Animal Department. Trace concentrations of isoflurane and nitrous oxide were directly measured every minute in the breathing zone by means of a photoacoustic infrared spectrometer in two different operating rooms (OR) with an air turnover of 17 changes per hour. In one OR the 8-hour time-weighted average (mean +/- SEM) was calculated to be 12.3 +/- 9.9 ppm nitrous oxide and 1.9 +/- 2.5 ppm isoflurane. The other OR, where only isoflurane was used, was contaminated with 5.3 +/- 8.1 ppm isoflurane. In the first OR, the trace gas concentrations were low and comparable to values obtained under human anaesthesia in adults and children. The higher contamination in the second OR resulted from performing inhalational anaesthesia with an open mask system in birds and small animals. Although the mean values were below the recommended occupational exposure standards, some high peak values (> 300 ppm isoflurane) violated these threshold limits. We recommend the use of a local scavenging device, if other alternatives such as total intravenous anaesthesia are not possible.

[Interscalene plexus block for mobilizing chronic shoulder stiffness]. / Die interskalenäre Plexus-Blockade zur Mobilisation bei chronischer Schultersteife.

INTRODUCTION: After mobilisation of a frozen shoulder, patients should work with a physiotherapist one to two times a day. In the remaining time patients must exercise on their own: otherwise, the shoulder is likely to become less mobile. Exercise is only possible in the absence of pain. Therefore, adequate analgesic therapy for four to five days after the first mobilisation is of great importance. We used interscalene blockade of the brachial plexus to achieve mobilisation in patients suffering from a painful frozen shoulder. We investigated the efficacy of this technique by registering the use of additional analgesics and documenting the patient's assessment. The observation time was 18 months. METHODS: Thirty-seven patients were treated with a plexus block using a catheter inserted at the affected side. Catheter location was verified with electric nerve stimulation. In all patients a bolus of 20 ml bupivacaine 0.375% was given for initial mobilisation, followed by 10 ml bupivacaine 0.25% every 6 hours. RESULTS: In 34 of 37 (92%) patients, the shoulder could be mobilised without general anaesthesia. Thirty-three of 37 (89%) patients did not need any additional analgesics during the following mobilizations. The mean duration of catheter treatment was 4 days; no infections occurred. The following side effects were observed at the first mobilisation: Horner's syndrome in 20 patients (54%), paresis of the recurrent nerve in 9 patients (24%) and paresis of the phrenic nerve in 6 patients (16%). During subsequent treatment, Horner's syndrome was observed in 15 patients (41%) and a paresis of the recurrent nerve in 8 patients (22%). In an interview after the end of the treatment period all patients stated that they would use this method again if necessary. CONCLUSIONS: With the use of this regional anaesthesia technique it was possible to provide comfortable pain therapy during the mobilisation period. In order to achieve sufficient analgesia with only a mild motor blockade of the motoneurons, the exact location of the catheter tip is important. The latter can be verified by electrical stimulation.

[Analgosedation of the ventilated intensive care patient]. / Analgosedierung des beatmeten Intensivpatienten.

Seven different schemes for analgesic anaesthesia were investigated for their clinical applicability, potential side effects, and impacts on circulation parameters of the systemic and pulmonary (peripheral) circulation as well as on the intracranial pressure. In all, so patients per group were treated. The results revealed different reactions of patients, such as a higher incidence of disturbances of the autonomic nervous system and excitation after medication withdrawal. Favourable effects not only on clinical reactions but also on circulation parameters were seen during fentanyl/midazolam or alfentanil/midazolam therapy. In several instances, a clear increase in the right atrial and the pulmonary arterial mean pressure as well as the intracranial pressure was observed during ketamine/flunitrazepam therapy. The combinations pethidine/promethazine or pethidine/flunitrazepam also showed clear side effects on the circulation and evoked an increase in the intracranial pressure. Fentanyl/midazolam or alfentanil/midazolam treatments were the most favourable combinations for most of the patients who were artificially respirated.

[Arousal in various analgosedation schedules]. / Aufwachverhalten bei verschiedenen Analgosedierungsschemata.

The patterns of recovery of patients who received seven different analgesic and sedative treatments were investigated with regard to the time at which the subjects awoke. For observations of the neurologic status, we developed a special score. The analgesic and sedative therapies were given at three various doses. The combination of fentanyl/midazolam, alfentanil/midazolam and ketamine/flunitrazepam showed the best results. Piritramid/promethazine, pethidine/flunitrazepam, pethidine/promethazine and tramadol/methohexital required more time for awakening. On the basis of these results, we prefer to use the combination of fentanyl/midazolam, alfentanil/midazolam and ketamine/flunitrazepam to judge all patients' neurologic scores.