A comparison of the intubating laryngeal mask airway and the Bonfils intubation fibrescope in patients with predicted difficult airways.

Tracheal intubation with the intubating laryngeal mask airway or the Bonfils intubation fibrescope was performed in 80 patients with predicted difficult airways. Mallampati score, thyromental distance, mouth opening and mobility of the atlanto-occipital joint were used to predict difficult airways. The overall success rate, time to the first adequate lung ventilation and time taken for the successful placement of the tracheal tube were recorded, as well as a subjective assessment of the handling of the device and the incidence of postoperative sore throat and hoarseness. The median [range] time to the first adequate ventilation was significantly shorter with the intubating laryngeal mask airway than with the Bonfils intubation fibrescope (28 [6-85] s vs. 40 [23-77] s, p < 0.005). Tracheal intubation was significantly slower with the intubating laryngeal mask airway than with the Bonfils intubation fibrescope (76 [45-155] s vs. 40 [23-77] s, p < 0.0001. Patients in the Bonfils group suffered less sore throat and hoarseness than those in the other group.

Plasma concentration of ropivacaine after intercostal blocks for video-assisted thoracic surgery.

BACKGROUND: Absorption of local anaesthetics following intercostal blocks is rapid. Therefore, plasma concentrations of ropivacaine during intercostal blocks with ropivacaine 2, 5, 7.5 and 10 mg ml-1 (ropivacaine 5 ml injected into each of four intercostal spaces) in patients undergoing video-assisted thoracic surgery were determined. METHODS: After informed consent and ethics committee approval, 64 patients were randomly allocated to four groups for intercostal nerve block (ropivacaine 2, 5, 7.5 or 10 mg ml-1 at the end of surgery). Central (mixed) venous and arterial plasma samples were collected before the start of intercostal application, and 2, 5, 10, 15, 20, 30, 45, 60 and 90 min afterwards. Plasma concentrations of ropivacaine were measured by high performance liquid chromatography. RESULTS: Maximum venous plasma concentrations occurred after the mean times of 10.7 (range, 5-15), 10.8 (5-20), 11.3 (5-20) and 12.2 (5-45) min, respectively for each group. The groups had mean concentrations of 1.3 (SD, 0.6; range, 0.3-2.3), 2.1 (1.0; 0.5-4.5), 2.4 (1.0; 1.2-5.1) and 2.5 (0.9; 1.7-5.6) micrograms ml-1, respectively. Maximum arterial plasma concentration following 1.0% ropivacaine occurred after 16 (5-45) min with a mean of 2.3 (0.6; 1.5-3.6) micrograms ml-1. No signs of central nervous system or cardiac toxicity were observed. CONCLUSIONS: After intercostal blocks the absorption of ropivacaine is rapid compared with other techniques for regional anaesthesia and results in relatively high venous and arterial plasma concentrations, especially if a dose of 100 mg or more is used.

Pharmacokinetics and pharmacodynamics of ropivacaine 2 mg/mL, 5 mg/mL, or 7.5 mg/mL after ilioinguinal blockade for inguinal hernia repair in adults.

UNLABELLED: The aim of our study was to evaluate the pharmacokinetics and pharmacodynamics of ropivacaine in ilioinguinal-iliohypogastric blocks (IIB). After ethics committee approval and informed consent, 80 male adults scheduled for inguinal hernia repair were enrolled and randomized into four groups. After induction of general anesthesia, an IIB was performed double blinded in Groups 1, 2, and 3 with 0.25 mL/kg ropivacaine 2 mg/mL, 5 mg/mL, or 7.5 mg/mL and with saline in the Control group. Plasma concentration of ropivacaine was determined in venous blood using reversed-phase high-performance liquid chromatography. IIB with ropivacaine resulted in peak plasma concentrations of 0.3+/-0.15 microg/mL (Group 1) (mean +/- SD), 0.75+/-0.45 microg/mL (Group 2), or 1.57+/-0.82 microg/mL (Group 3). These concentrations occurred after 30 (15-60) min, median (range), 30 (10-60) min, and 45 (15-60) min, in the respective groups. Three of 19 patients in Group 1, 6 of 18 in Group 2, and 5 of 20 in Group 3 did not need any additional analgesics within 24 h postoperatively, but all 20 control patients did. Time to the first demand for analgesia was significantly shorter in the Control group (median 0.3 h [range 0-2.8]) compared with 1.5 h (0.5-24 h), 2 h (0.5-24 h), and 2 h (1.0-24 h) in Groups 1, 2, and 3, respectively. Three patients in Group 3 had a postoperative motor block of the femoral nerve. In conclusion, a ropivacaine dose of 0.25 mL/kg of 5 mg/mL seems adequate for IIB accompanying general anesthesia for postoperative pain relief. However, the pharmacokinetic results obtained suggest that even larger doses (0.25 mL/kg of 7.5 mg/mL ropivacaine) for IIB do not result in plasma concentrations in a toxic range. IMPLICATIONS: Ropivacaine, a new local anesthetic, proved to be effective for pain relief after hernia repair in ilioinguinal blocks accompanying general anesthesia. Plasma concentrations peaked after 30-45 min, and were within safe limits after application of 0.25 mL/kg of 2, 5, or 7.5 mg/mL ropivacaine.

Muscular involvement in Behçet's disease: case report and review of the literature.

Acute necrotizing myositis is described in a 22-yr-old man with clinically diagnosed Behçet's disease. Light microscopic examination revealed a prominently granulocytic-monocytic infiltration of the muscle with severe necrosis. An infectious (bacterial, fungal or parasitic) etiology could be excluded by specific staining techniques and by immunohistochemistry. Vascular deposition of immune complexes was detected by direct immunofluorescence. Electron microscopy revealed severe structural damage and phagocytosis of muscle fibers. In the endomysium, leukocytes and occasional erythrocytes were found. Virus-like particles were not seen. The relevant literature on muscular involvement in Behçet's disease is reviewed. It is suggested that two different stages of inflammation occur in Behçet's disease. In the acute stage it presents as a granulocytic-monocytic necrotizing reaction developing from a neutrophil-mediated vasculitis. In the later phase lymphocytic infiltrations predominate. Despite the rare involvement of muscles the diagnosis of Behçet's disease should be considered particularly in younger patients presenting with muscular symptoms like pain and swelling pre-dominantly of the lower extremities.

Morphology of non-vascular intracerebral fluid spaces.

In the electron microscope the value for the extracellular space (ECS) in the mammalian CNS was suggested of several percent to about one third dependent on the method how it was evaluated. Since von Harreveld introduced 1965 cryofixation to estimate the extension of the ECS, the method has been never applied in brain edema research. We carried out improved low temperature methods to measure the extracellular space of the mammalian CNS in physiological conditions. Small samples of brain tissue were cryofixed by slam freezing on a precooled metal mirror and substituted with ethanol at -95 degrees C over 17 hours. The embedding procedure was carried out at -22 degrees C with LR-White under UV-irradiation. ECS was measured computer assisted with Bioquant Software. The values for the ECS of the cryofixed normal rat brain were more than twice compared to the usual transmission electron microscopy (16.3% to 7.4%, p < 0.01) and close to those estimated by von Harreveld (18.1-25.5%, 1965). It was interesting that the data obtained in cryofixed normal rat brain correspond to the extension measured in rat brain with irradiation edema, which was conventionally treated for EM. Greater variance of ECS in cryofixed brain (16.3% +/- 3.4) demonstrate that it is far more variable than expected. This data correspond closely to the in vivo ECS. The morphological evaluation of brain edema should be revised under this premise.