[Remifentanil for oocyte retrieval: A new single-agent monitored anaesthesia care technique]. / Infusionsanalgesie mit Remifentanil.Ein neues Verfahren zur Schmerzausschaltung bei der transvaginalen Follikelpunktion vor In-vitro-Fertilisation.

INTRODUCTION: Transvaginal puncture for oocyte retrieval is a short-lasting but painful procedure. We hypothesized that a sole infusion of the ultra-short acting mu-agonist remifentanil may be a suitable and well-controllable single-agent analgesic technique that can dose-dependently be applied to spontaneously breathing patients. METHODS: Fifty consenting adult women were enrolled in this prospective trial. A sedative premedication was omitted, all patients received 3 L/min of inhaled oxygen, and a sole remifentanil infusion was started with 0.25 microg/kg/min. Remifentanil was adjusted as needed for pain relief (in steps of 0.05 microg/kg/min) and finished after the last puncture. Dosage requirements, vital functions, oxygen saturation (as achieved by pulse oximetry, psO(2)), adverse drug effects and the level of sedation (LOS 1-5; 1 = asleep/unarousable, 4 = calm/awake) were recorded. Remifentanil plasma concentrations were achieved by STANPUMP pharmacokinetic simulation. Data are presented as mean +/- SD. RESULTS: A total of 50 women (31.8 +/- 5.1 yr, 67.3 +/- 14. ASA I or II ) were investigated. Follicular aspiration lasted 10.8+/-5.2 min, and remifentanil was infused for 19.7+/-8.3 min. Dosage requirements were 0.25 microg/kg/min in 70% of all patients, 0.3 microg/kg/min in 22%, 0.2 microg/kg/min in 6%, and 0.4 microg/kg/min in 2% of all cases. Vital signs (baseline, after 1(st) puncture, end of surgery) nearly remained unchanged: heart frequency = 85 +/- 15, 87 +/- 17, 90 +/- 17 bpm, systolic blood pressure = 129 +/- 12, 132 +/- 13, 131 +/- 14 mmHg; respiratory rate = 116 +/- 4, 15 +/- 4 breaths/min; psO(2) = 99 +/- 1, 99 +/- 1, 99 +/- 2%. LOS was 4.0 (all), 3.9 +/- 0.3, 3.9 +/- 0.3. Remifentanil plasma concentrations were 5.0 +/- 1.3 ng/mL at the start, 6.6 +/- 1.3 at the end of surgery and 1.2 +/- 0.5 at PACU arrival. Adverse drug effects: 54% itching, no muscle rigidity. 94% of all women would choose this technique again. CONCLUSIONS: The sole infusion of remifentanil is a suitable and satisfying single-agent monitored anaesthesia care technique for oocyte retrieval. However, close anaesthetic observation - especially of the respiratory function - is mandatory.

[Remifentanil with propofol or isoflurane. A comparison of the recovery times after arthroscopic surgery]. / Remifentanil mit Propofol oder Isofluran. Ein Vergleich des Aufwachverhaltens bei arthroskopischen Eingriffen.

OBJECTIVES: Due to its unique pharmacokinetics, the new esterase-metabolised opioid remifentanil results in rapid post-anesthesia recovery. The aim of this clinical investigation was to compare recovery times after remifentanil anaesthesia in combination with hypnotic concentrations of either propofol or isoflurane. Dosages used in the study protocol were based on recommendations by the pharmaceutical manufacturer. METHODS: Patients (ASA status I-II) scheduled for elective arthroscopy were included in this trial. Without premedication in the morning, anaesthesia was induced identically in both groups: remifentanil bolus (1 microgram/kg), start of remifentanil-infusion (0.5 micrograms/kg/min), followed immediately by propofol (ca. 2 mg/kg). For maintenance of anaesthesia remifentanil (0.25 micrograms/kg/min) was combined with either a propofol infusion of 0.1 mg/kg/min or 0.5 MAC isoflurane (= 0.6 vol. %) in O2/air. Anaesthetic delivery was discontinued simultaneously with termination of surgery and recovery times were recorded. RESULTS: A total of 40 patients were studied at random in two groups of 20 each with comparable demographic data and anaesthetic technique (Tables 1 and 2). In both groups emergence was very rapid. Recovery times were significantly shorter for remifentanil-isoflurane than for remifentanil-propofol (Table 3): spontaneous ventilation 5.1 vs 8.1 min (P < 0.05), extubation 5.5 vs 8.6 min (P < 0.02), post-anaesthesia recovery score > or = 9 of 10 points 6.2 vs 11.3 min (P < 0.01), and arrival at PACU 16.2 vs 19.2 min (P < 0.01). Mild to moderate shivering was noted in 40% of all patients (9 cases following isoflurane, 7 following propofol). CONCLUSIONS: Using the manufacturer's recommended dosages, emergence after remifentanil anaesthesia is more rapid with 0.5 MAC isoflurane than with 0.1 mg/kg/min propofol. These results are most probably due to the different pharmacological properties of both co-anaesthetics, especially the applied dosages, and to different interactions with remifentanil. Present clinical experience suggests that a further dose reduction, especially for propofol, is possible. For both remifentanil groups emergence was remarkably rapid between return of consciousness and the awake state (on-off phenomenon), which might contribute to post-anaesthesia safety.

[Accuracy of measurement and overestimation of CO2 of two capnometers intended for potential use in emergency medicine]. / Uberprüfung von CO2-Messgenauigkeit und CO2-Bereichspräzision zweier für den potentiellen Einsatz im Rettungsdienst konzipierter Kapnometer.

UNLABELLED: Capnometry, the noninvasive measurement of end-expiratory CO2 concentration (cCO2, vol%) or calculation of its respective partial pressure (pCO2; mmHg) is an established method. However, for prehospital settings, capnometry is still used very restrictively, mainly owing to the respective devices used. The prerequisite for their use is sufficient accuracy (+/-2 mmHg) and easy handling. Two special capnometers (STAT CAP. Nellcor: mainstream, semiquantitative estimation; Capnocheck 8200, BCI: sidestream, quantitative measurement, numeric display), developed recently for potential use in emergency medicine, are said to fit these criteria. Therefore, the objective of the present investigation was to assess the accuracy and precision of both devices, comparing methods under standardized in vitro (reference gases) and in vivo (intubated and ventilated patients) conditions. METHODS: Both devices ("STAT CAP": pCO2 range, light bars; "Capnocheck 8200") were evaluated regarding the accuracy of pCO2 (Capnocheck) and the precision of the CO2 range (STAT CAP). Tests were performed with four dry gas mixtures (STPD) of defined composition and during ventilation of 20 intubated patients (BTPS). All measurements were compared with the alveolar gas monitor "AGM 1304" (Brüel & Kjaer, Denmark) as a reference method with a proven +/- 1 mmHg accuracy of pCO2 measurement. RESULTS: The "Capnocheck" (BCI) presented an accuracy of the pregiven pCO2 of 0.7-1.4 mmHg (dry gas mixtures, STPD) and an overestimation of 0.2 +/- 4.1 mmHg (BTPS) during ventilation with pure oxygen; inaccuracy during ventilation with 70% N2O in O2 proved to be + 1.2 +/- 1.7 mmHg (BTPS). Nellcor's "STAT CAP" failed to reach the target value in 10% of analyses, as shown by the respective segment bar of the display. CONCLUSION: Evaluation of the accuracy of capnometers must focus on the necessary pH2O correction and the possible effects exercised by O2 (and N2O) as well as the possible dependence on barometric pressure (if pCO2, mmHg, is the desired value). The "Capnocheck" showed an accuracy of more than 2 mmHg in dry gas mixtures as well as in humidified air. Concerning the practical use during constant artificial ventilation, the digital display and accuracy of the sidestream capnometer allow for reliable conclusions on patients' ventilation and circulation (CO2 elimination). The 90% accuracy of the segment bar display of Nellcor's "STAT CAP", per se covering only a rather broad range of 20 mmHg, obviously does not provide more than a rough overview. Therefore, the STAT CAP cannot be recommended for prehospital capnometry in the field. However, both the accuracy of the BCI capnometer (Capnocheck) and its numeric display and easy handling strongly recommend this device also for clinical use.

Comparison of two solutions with different glucose concentrations for infusion therapy during laparotomies in infants.

OBJECTIVE: Comparison of two commercially available solutions for intraoperative infusion therapy during laparotomies in infants using a standardized anesthetic technique (combination of general anesthesia with a caudal block). DESIGN: Prospective, randomized. SETTING: Infusion therapy during laparotomies in infants. PATIENTS AND METHODS: 12 infants aged 1-12 weeks (group I) and 12 infants aged 5-14 months (group II) received at random either solution A with 2.5% glucose and 70 mmol Na+ or solution B with 5.5% glucose and 100 mmol Na+ at a rate of 8 ml/kg/h. INTERVENTIONS: Central venous blood samples after induction of anesthesia and every 60 min for analysis of blood glucose, electrolyte, and hemoglobin concentrations. End of surgery: urine output during the operation and urine glucose and sodium concentrations. Statistical significance within the group: Friedmann Test, between the groups: U test by Wilcoxon, Mann and Witney. SIGNIFICANCE: p < 0.05. RESULTS (given as median and range): In group I blood glucose concentrations rose significantly during surgery, however, there was no significant difference between group A or B after 1 h. A: 234 mg/dl (156-351) vs B: 239 mg/dl (166-329)) or 2 h: A: 254 mg/dl (166-331) vs B: 272 mg/dl (176-468). In group II blood glucose levels rose significantly during surgery, however, children of group B showed significantly higher blood glucose levels than group A after 1 h [A: 119 mg/dl (114-227), B: 203 mg/dl (162-238)], 2 h [A: 154 mg/ml (106-185), B: 284 mg/dl (243-317)] or 3 h [A: 159 mg/dl (116-218), B: 248 mg/dl (201-363)]. The plasma and urine sodium concentrations did statistically not differ between the two solutions. CONCLUSIONS: Solutions containing 5.5% glucose infused with 8 ml/kg/h caused in both age groups of infants intolerable hyperglycemias. In young infants, also a solution containing 2.5% glucose infused at a rate of 8 ml/kg/h leads to hyperglycemia, while in older children this amount of glucose is tolerated. It is recommended that for abdominal surgery in young infants glucose and fluid substitution is separated, in order to infuse glucose at an even lower rate. Still, blood glucose levels have to be monitored closely.

[The effect of midazolam after intranasal administration on spontaneous respiration and respiratory control in young children]. / Der Einfluss von Midazolam nach intranasaler Gabe auf Spontanatmung und Atemregulation bei Kleinkindern.

AIM: The aim of this study was to investigate the influence of intranasally administered midazolam in different doses on spontaneous respiration in children. METHODS: 40 children received in randomised order 0.2, 0.4 or 0.6 mg/kg b.w. midazolam intranasally or NaCl 0.9% as control. 10 minutes later, anaesthesia was induced by inhalation of halothane, nitrous oxide and oxygen. The children were breathing spontaneously at a PEEP of 5 cm H2O on a circle system with a fresh gas flow of 61/min (FIO2 = 0.33). Intubation was performed in deep anaesthesia without muscle relaxant. Halothane concentration was reduced to an endtidal concentration of 0.4 Vol%. With a baby pneumotachograph, minute ventilation, tidal volume, peak inspiratory and expiratory flow and respiratory rate were recorded during quiet breathing. Endtidal pCO2 was measured. Ventilation was then stimulated with 0.2 and 0.41/min CO2 and the same parameters were recorded. Regression analysis was performed for minute ventilation and endtidal pCO2 to obtain the slope which is a parameter for the sensitivity of the chemoreceptor mediated control of ventilation. RESULTS: The tidal volume and peak inspiratory flow were significantly reduced for a dose of 0.6 mg/kg compared to the control group. No statistical difference could be found for any other parameter between the control and study groups. CONCLUSION: We conclude that nasally administered midazolam reduces tidal volume and inspiratory peak flow in spontaneously breathing children at a dose of 0.6 mg/kg b.w. compared to control during halothane--nitrous oxide--oxygen anaesthesia. The CO2 mediated control of respiration under this condition is preserved.

[Spinal anesthesia in infancy using bupivacaine 0.5%. The effect of an adrenaline addition on duration and hemodynamics]. / Spinalanästhesie im Säuglingsalter mit Bupivacain 0.5%. Der Einfluss eines Adrenalinzusatzes auf Wirkdauer und Hämodynamik.

The duration of spinal anaesthesia in infants is short compared to adult patients. When tetracaine is used, the addition of epinephrine significantly prolongs the duration. For bupivacaine, however, the influence of epinephrine on the duration is not clear. We investigated the effects of epinephrine 1:200,000 added to bupivacaine 0.5% on duration and haemodynamics. PATIENTS AND METHODS. Ten former pre-term infants with postnatal respiratory problems, scheduled for bilateral inguinal hernia repair, were enrolled in the study after informed parental consent had been obtained. The infants were fasted at least 4 h prior to surgery. If they did not receive i.v. infusions before surgery, a bolus of 10 ml/kg Ringer's acetate was injected after inserting the i.v. cannula, followed by a continuous infusion of 8 ml/kg 2/3 N NaCl with 5% dextrose. Spinal anaesthesia was performed in a sitting position with 0.6 ml bupivacaine 0.5%. Five patients received plain bupivacaine (group I) and five bupivacaine with epinephrine 1:200,000 (group II). Heart rate registered by ECG and non-invasive blood pressure were recorded prior to positioning the baby for lumbar puncture and 2, 5, 10, and 20 min after injection of bupivacaine. The duration of spinal anaesthesia was defined as the time from injection to the time when the first movements of the legs were observed after stimulation. For testing statistical differences the U test was used between the groups and the Wilcoxon and Wilcox test within the groups. RESULTS. (expressed as median and range). Additional epinephrine significantly prolonged the duration of spinal anaesthesia (group II: 95 min [60-120] vs group I: 50 min [37-85]). Haemodynamic parameters did not differ at any time between or within the groups. In group I, one infant had high spinal anaesthesia with impaired respiration but without cardiovascular effects; after 10 min of assisted ventilation by mask, sufficient respiration as judged by pulse oximetry and clinical observation had returned. The duration of spinal anaesthesia in this child was 60 min. CONCLUSIONS. Epinephrine 1:200,000 significantly prolongs the duration of spinal anaesthesia in former preterm infants. Haemodynamic parameters in this age group remain unchanged during spinal anaesthesia and are not influenced by the addition of epinephrine.

Characterization of two monoclonal antibodies against secretory proteinase of Candida tropicalis DSM 4238.

Two murine IgM monoclonal antibodies (mAb; MT1 and MT2), which were produced against the secretory aspartic proteinase of Candida tropicalis DSM 4238, are described. Both antibodies reacted with the native and denatured conformations of the homologous proteinase antigen but showed different patterns of reactivity with other related proteinases (Candida albicans CBS 2730, serotype A; C. albicans ATCC 48867, serotype B; Candida parapsilosis DSM 4237) and with porcine pepsin. Neither of the antibodies inhibited the proteolytic activity of the homologous enzyme. MT1 also reacted with mannoproteins of C. tropicalis DSM 4238 and C. albicans CBS 2730 and immunofluorescence revealed that this antibody bound to the surface of blastoconidia and pseudomycelia of these two Candida species. A reaction with blastoconidia only was observed with C. albicans serotype B. MT1 also reacted weakly with Candida guilliermondii, but not with C. parapsilosis, Candida glabrata, Candida krusei or Candida kefyr. MT2 did not bind to fungal surfaces. Preliminary experiments suggested that mAb MT1 may recognize a carbohydrate epitope, while MT2 binds to an epitope consisting of the protein part of the enzyme. The two antibodies were used in an ELISA for the detection of proteinase antigen. ELISA with MT1 or MT2 as coating antibodies and a specific protein epitope recognizing mAb-biotin conjugate was able to detect 4 ng ml-1 of antigen. Trials with 26 sera from fungemic patients and 14 sera from controls suggest that MT2 is of potential value in antigen-directed serodiagnosis.