Anaesthesia
-
Comparative Study
SNAP index and Bispectral index during different states of propofol/remifentanil anaesthesia.
The accuracy of the new SNAP index with the Bispectral index (BIS) to distinguish different states of propofol/remifentanil anaesthesia was compared in 19 female patients who were undergoing minor gynaecological surgery. Comparisons of the SNAP index, BIS, spectral edge frequency, mean arterial blood pressure and heart rate were performed. The ability of all parameters to distinguish between the steps of anaesthesia -awake vs. loss of response, awake vs. anaesthesia, anaesthesia vs. first reaction and anaesthesia vs. extubation - were analysed with the prediction probability. ⋯ Only the BIS showed no overlap between the investigated steps of anaesthesia. Both the SNAP index and BIS failed to differentiate the nuances of anaesthesia. The SNAP index and BIS were superior to mean arterial blood pressure and heart rate and spectral edge frequency in distinguishing between different steps of anaesthesia with propofol and remifentanil and provided useful additional information.
-
The aim of this study was to investigate cuff pressure changes found in disposable size 3 laryngeal mask airways (LMAs) from different manufacturers during nitrous oxide exposure and to compare the results with the re-usable Classic LMA. In an in vitro experiment, laryngeal mask airway cuff pressures starting from a baseline pressure of 40 cm H(2)O were recorded using a pressure transducer for 60 min with the laryngeal mask airway cuff exposed to 66% N(2)O in oxygen. ⋯ The cuff pressure increase following 60 min of nitrous oxide exposure was 13.0 +/- 1.1 and 14.6 +/- 0.7 cm H(2)O in the Intersurgical and Unique laryngeal mask airways, respectively, which was significantly lower than the cuff pressure increase in the Soft Seal and in the Ambu laryngeal mask airways (28.3 +/- 2.9 and 30.9 +/- 1.2 cm H(2)O, respectively). Unlike the re-usable Classic LMA and the disposable Marshall laryngeal mask airway, which have silicone cuffs, the disposable Ambu, Intersurgical, Portex Soft Seal and Unique laryngeal mask airways have cuffs constructed from PVC, which seems to be less susceptible to hyperinflation caused by nitrous oxide diffusion.
-
Eight hundred and ninety-six incidents relating to drug error were reported to the Australian Incident Monitoring Study. Syringe and drug preparation errors accounted for 452 (50.4%) incidents, including 169 (18.9%) involving syringe swaps where the drug was correctly labelled but given in error, and 187 (20.8%) due to selection of the wrong ampoule or drug labelling errors. The drugs most commonly involved were neuromuscular blocking agents, followed by opioids. ⋯ Factors minimising the events were prior experience and training, rechecking equipment and monitors capable of detecting the incident. The information gained suggests areas where improved guidelines are required to reduce the incidence of drug error. Further research is required into the effectiveness of preventive strategies.