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Ondansetron, a selective 5-HT3 receptor antagonist, has recently been shown, in a dose of 8 mg, to be superior to 1.25 mg droperidol in preventing postoperative vomiting. There are indications that a dose of 4 mg of ondansetron may be just as effective in reducing postoperative nausea and vomiting as a dose of 8 mg. The aim of this study was to evaluate the efficacy and the adverse effects of 4 mg ondansetron in the prevention of postoperative nausea and vomiting compared to droperidol in patients undergoing surgery with inhalation anaesthesia supplemented with alfentanil. METHODS. Following institutional approval, 40 ASA physical status I and II women scheduled for minor gynaecological surgery gave informed consent to participate in this randomized, double-blind comparative study. Five minutes before induction of general anaesthesia, 20 patients received a single intravenous (i.v.) dose of 4 mg of ondansetron and the remaining 20 received 1.25 mg droperidol i.v. Anaesthesia was induced with 2.1-4 mg/kg of thiopental and 0.1 mg of alfentanil i.v. and maintained with 65% nitrous oxide and 1.5%-3% enflurane in oxygen. On pain stimuli another 0.2-0.4 mg of alfentanil was given. Total effective antiemetic response was defined as the absence of nausea and vomiting for 24 h postoperatively. The incidence of nausea, vomiting and the number of patients showing total antiemetic response as well as the incidence of adverse effects were compared with the chi 2 test and P < 0.05 was considered significant. RESULTS. Patients were similar with respect to age, height, body weight and total anaesthetic agents received. Duration of anaesthesia and the time until awakening was not significantly different among groups. Postoperatively 7 out of 20 patients given 4 mg of ondansetron and 3 out of 20 patients with droperidol vomited (n.s.). The incidence of nausea was 11 out of 20 in the ondansetron group, and 4 out of 20 in the droperidol group (P < 0.05). Sixteen patients in the droperidol group and 8 patients in the ondansetron group showed a total effective antiemetic response (P < 0.05). Postoperative sedation and well-being scores did not differ significantly among groups. CONCLUSION. Our results show that for the prevention of postoperative nausea and vomiting 4 mg of Ondansetron was inferior to 1.25 mg of droperidol. The drugs were given intravenously prior to general anaesthesia for minor gynaecological surgery with nitrous oxide and enflurane in oxygen supplemented with small boluses of alfentanil. [ABSTRACT FROM AUTHOR]

Patients' fears of anesthesia mostly focus on a possibly inadequate anesthetic effect, on postoperative wound pain and/or nausea and vomiting (PONV). Concerning the possibility of an inadequate anesthetic effect, patients usually express two different kinds of fears: first, that they might stay conscious during surgery («Awareness») without it being noticed, and second that they might not wake up again after the operation or that they might sustain neurological damages or deficits after the anesthesia. Last but not least patients are afraid they might suffer from substantial pain after waking up from the anesthesia. In this article we take a closer look at these aspects and discuss ways and possibilities of handling them, suggesting useful approaches for the general practitioner when talking these issues through with his patients prior to an operation.

Objective: The aim of this study was to examine the psychological effects, well-being and side effects after various doses of oral midazolam medication., Methods: After informed consent has been obtained and following the approval by the institutional ethical committee, 80 adult patients in the ASA physical status I and II were randomly assigned to one of five different premedication groups: 3.75, 7.5, 11.25, 15 mg midazolam, and placebo. The medication was given in a double-blind fashion 60 min before induction of general anaesthesia for various surgical procedures. At 3 definite stages (before premedication, 30 and 60 min after premedication), blood pressure, heart rate, transcutaneous oxygen saturation and respiratory rate were measured. Sedation and well-being were graded according to a 5-point scale, and the subjective anxiety level was assessed according a visual analogue scale (range 0-100 mm). Anterograde and retrograde amnesia were measured by recall of auditive and visual stimuli. Finally, patients were asked whether in case of future surgery they would prefer the same or a different medication., Results: Demographic data were similar in all groups. There was no significant difference in respiratory rate, oxygen saturation, blood pressure or heart rate. Alertness declined only after 60 min in the groups treated with 7.5 mg and more midazolam. During the entire measurement period, anxiolysis was not different from placebo in any of the midazolam groups. In comparison to placebo, all midazolam groups showed a statistically significant and dose dependent anterograde amnesia for visual stimuli. Subjective well-being scores showed no differences between the groups. Only few side effects were seen following doses of 7.5 mg and higher, including ptosis, strabismus, diplopia, speech disorders, disorientation and vertigo. The majority of patients in all groups indicated a wish for the same medication in case of future anaesthesia for surgical interventions., Conclusions: Midazolam administered orally prior to surgical procedures showed marked interindividual variability. Sedation and amnesia were dose-dependent and were evaluated by the patients as acceptable. Anxiolysis was not significantly different from placebo. A dose of 7.5 mg midazolam showed the best relation between desirable and undesirable effects. Adequate attention given to the patient by the anaesthesiologist prior to surgery seems to be as important and beneficial as oral medication with midazolam.

Since there continues to be a high incidence of postoperative nausea and vomiting associated with many types of surgery, and the standard antiemetics often do not achieve satisfactory results, there have been attempts to use the 5-HT3 antagonists. This group of substances is relatively new, but has already been used successfully as an antiemetic during chemotherapy. To date, results are on hand for four different 5-HT3 receptor blockers: ondansetron, tropisetron, granisetron and dolasetron. Applied intravenously, all four have been effective both in prophylaxis and also as therapy for postoperative emesis. Except for ondansetron, there is so far no definitely clear knowledge about the lowest possible effective dosage. The entire group is well tolerated: only occasional and minor side effects have been reported. Even though not all the hopes originally set in the 5-HT3 group of antagonists have been fulfilled, progress has nevertheless been achieved. Especially noteworthy points are a positive cost-effectiveness relationship of these drugs and their appropriate use in case of the proper indications.

Ondansetron, a selective 5-HT3 receptor antagonist, has recently been shown, in a dose of 8 mg, to be superior to 1.25 mg droperidol in preventing postoperative vomiting. There are indications that a dose of 4 mg of ondansetron may be just as effective in reducing postoperative nausea and vomiting as a dose of 8 mg. The aim of this study was to evaluate the efficacy and the adverse effects of 4 mg ondansetron in the prevention of postoperative nausea and vomiting compared to droperidol in patients undergoing surgery with inhalation anaesthesia supplemented with alfentanil. METHODS. Following institutional approval, 40 ASA physical status I and II women scheduled for minor gynaecological surgery gave informed consent to participate in this randomized, double-blind comparative study. Five minutes before induction of general anaesthesia, 20 patients received a single intravenous (i.v.) dose of 4 mg of ondansetron and the remaining 20 received 1.25 mg droperidol i.v. Anaesthesia was induced with 2.1-4 mg/kg of thiopental and 0.1 mg of alfentanil i.v. and maintained with 65% nitrous oxide and 1.5%-3% enflurane in oxygen. On pain stimuli another 0.2-0.4 mg of alfentanil was given. Total effective antiemetic response was defined as the absence of nausea and vomiting for 24 h postoperatively. The incidence of nausea, vomiting and the number of patients showing total antiemetic response as well as the incidence of adverse effects were compared with the chi 2 test and P < 0.05 was considered significant. RESULTS. Patients were similar with respect to age, height, body weight and total anaesthetic agents received. Duration of anaesthesia and the time until awakening was not significantly different among groups. Postoperatively 7 out of 20 patients given 4 mg of ondansetron and 3 out of 20 patients with droperidol vomited (n.s.). The incidence of nausea was 11 out of 20 in the ondansetron group, and 4 out of 20 in the droperidol group (P < 0.05). Sixteen patients in the droperidol group and 8 patients in the ondansetron group showed a total effective antiemetic response (P < 0.05). Postoperative sedation and well-being scores did not differ significantly among groups. CONCLUSION. Our results show that for the prevention of postoperative nausea and vomiting 4 mg of Ondansetron was inferior to 1.25 mg of droperidol. The drugs were given intravenously prior to general anaesthesia for minor gynaecological surgery with nitrous oxide and enflurane in oxygen supplemented with small boluses of alfentanil.

A marked decrease in both personal and environmental pollution with anaesthetic gases as well as in costs is possible with anaesthesia machines which can be run with a low fresh gas flow (FGF) [9]. Low-flow anaesthesia can be performed with appropriately equipped circle systems, although strongly reduced FGF minimises the control of depth of anaesthesia and gas concentrations. Microprocessor-controlled feedback systems allow the utilisation of closed-circuit systems throughout the whole duration of anaesthesia, maintaining full anaesthetic control [3,5]. The aim of this investigation was to determine the costs resulting from gas consumption and clinical suitability of the recently marketed PhysioFlex anaesthesia machine. METHODS. We used a PhysioFlex (Physio, Hoofdorpp, Netherlands) in a series of 15 routine otorhinolaryngological interventions. After induction with thiopentone and suxamethonium, general anaesthesia was maintained with nitrous oxide in 30% oxygen and isoflurane and supplemented with fentanyl and atracurium. The expenditure of anaesthetic gases was recorded during a total of 61 h and 27 min and differentiated into its components. Anaesthetic gas uptake and costs were compared with different breathing systems (low-flow anaesthesia, semiclosed system and non-rebreathing system) under similar clinical conditions. RESULTS. The average minute volume was 6.84 (+/- 1.17) l and the expiratory isoflurane concentration was 0.91% (+/- 0.14%) (Table 1). These settings resulted in an oxygen expenditure of 27.9 (+/- 8.46) l/h with total costs of SFr. 0.04, nitrous oxide 11.9 (+/- 5.4) l/h and 0.27, isoflurane 3.9 ml/h and SFr. 5.42. In contrast, other breathing systems in analogous settings resulted in greater costs by a factor of 0.77 for low-flow anaesthesia (FGF 1 l/min), 2.47 for a semiclosed system (FGF 3 l/min) and 5.63 for a valve-controlled non-rebreathing system (FGF 6.84 l/min) (Table 2). DISCUSSION. The emission of anaesthetic gases can be lowered by measures that avoid unintended gas fallout, the application of filters, scavenging systems and efficient air circulation in operation and recovery rooms [8]. Above all, the use of the lowest possible FGF is advantageous for the patient insofar as better conditioned breathing gases are available, and economic and environmental effects are more significant (Table 3). With the method of quantitative anaesthesia as performed by the PhysioFlex, it is now possible to reduce gas expenditure according to the requirements of the patient as well as maintaining full control of anaesthesia depth. Simultaneously, multiple secured feedback control systems guarantee adequate monitoring and storage of respiratory and metabolic parameters. The duration of nitrous oxide wash-out can be a problem, in particular, when a changeover to O2/air is required.

Difficult intubations can occur in cases of anatomical or physiological abnormalities of the face and neck. They are frequently predictable when specific signs are evident preoperatively. There are still occasional unexpected difficulties during conventional laryngoscopy when common blades like the Macintosh and Foregger types are used. During the past 5 decades several authors have proposed many types of laryngoscopes and blades differing in length and shape, as well as various accessories such as guide-wires, prisms, and mirrors. METHOD. We modified a size 3 Macintosh blade by adding a mirror placed tangential to the external curve near the apex. This configuration allows both conventional direct visualisation of the vocal cords and non-direct viewing through the mirror. Insertion of the tube is facilitated using a specially shaped guide-wire. RESULTS. This equipment was used for orotracheal intubation in 20 patients with different degrees of direct laryngeal visibility prior to otolaryngologic endoscopy and surgery under general anaesthesia. Both methods of larynx visualisation were performed and compared. In 1 patient the mirror was not useful because it became fogged. In all the others we could avoid this problem by warming the blade in water. Only in 1 other case was the conventional view better and intubation seemed to be easier than when the mirror was used. In 15 patients the vocal cords were visualised better with the mirror, and intubation was performed by means of the guide-wire with the non-direct technique. In 2 of these cases difficult direct laryngoscopy of grades 3 and 4 according to the Cormack and Lehane classification was found. Four patients were difficult to intubate and neither type of laryngoscopy was ideal. It is notable that a satisfactory view was achieved in the mirror with much less effort. In particular, there was no need to introduce the blade as deeply or raise its apex as much as is usually done. CONCLUSION. The mirror-blade is a suitable device for management of unexpected difficult intubations. Because of its dual availability, it offers both direct and non-direct visualisation of the larynx. Handling of this mirror-blade can be practised extensively, which allows integration of this equipment in the "failed intubation drill". This should be an integral part of the teaching and training of anaesthesia personnel.

Case Report: After uneventful induction of general anesthesia, severe hypotension and cardiac arrest developed in a 39-year-old, non-atopic man following infusion of 20% mannitol 80 min after the beginning of anesthesia. It caused a systolic blood pressure of 40 mmHg during a period of 10 min and tachycardia followed by ventricular fibrillation. Immediate resuscitation measures, i.e., external cardiac compression, rapid infusion of 3,000 ml crystalloid and 1,000 ml colloid, central-venous application of suprarenin (2.4 mg total), lidocaine (100 mg), sodium bicarbonate (100 mmol), and two defibrillations, could alleviate the life-threatening reaction. The patient recovered a few hours later without any further sequelae., Allergologic Investigations: Allergologic studies with all drugs involved revealed a positive and specific reaction in an intradermal skin test to 1:100 diluted mannitol, as did in-vitro leucocyte histamine release to 20% and 2% mannitol. For all the other drugs, skin tests and leucocyte histamine release were negative or unspecific. Available RAST determinations to thiopental and suxamethonium were also negative. The total IgE level was normal., Conclusions: Reflecting the hypotension induced by histamine, the hematocrit rose from 0.4 to 0.5 even though the patient received a large amount of fluid before and during resuscitation. This can be explained by marked sequestration of plasma in the interstitial compartment, leading to hypovolemia. The clinical course and test results suggest that mannitol was the agent responsible for the anaphylactoid reaction.

Unlabelled: The aim of the study was to examine the analgesic efficacy and applicability of the two analgesic drugs nalbuphine and tramadol, administered by continuous i.v. infusion combined with a patient-controlled analgesia device (PCA)., Methods: With informed consent and approval of the ethical committee, 40 patients were studied after abdominal hysterectomy in a randomized, double-blind order. Twenty received an initial postoperative dose of 10 mg nalbuphine followed by a continuous infusion of 5 mg/h and the possibility of an additional 5 mg every 30 min. The other 20 received equipotent analgesia consisting of an initial bolus of 50 mg tramadol i.v. followed by a continuous infusion of 25 mg/h and the possibility of an additional 25 mg every 30 min. Analgesia, sedation, general well-being, and acceptance of the patients as well as blood pressure, heart rate, respiratory rate, and pulse-oximetric O2 saturation were measured regularly during a 5-h postoperative period. Data were analyzed using the Mann-Whitney test, with P less than 0.05 considered significant; results were expressed as mean +/- standard deviation., Results: The postoperative pain score on the visual analogue scale (0 to 10) fell with nalbuphine from 7.14 +/- 3.45 to 2.03 +/- 1.25 and with tramadol from 7.81 +/- 2.85 to 1.57 +/- 1.40. There were no significant differences between the two groups. PCA supplements were requested 21.7 times in the nalbuphine group and 27.3 times in the tramadol group. General well-being of the patients on a 4-point scale (0 to 3) improved for the nalbuphine group from 0.70 +/- 0.92 to 2.11 +/- 0.49 and for the tramadol group from 0.62 +/- 0.67 to 2.33 +/- 0.50, which was significantly better in the nalbuphine group after 45, 60, and 90 min.(ABSTRACT TRUNCATED AT 250 WORDS)