Anaesthesia
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Comparative Study
Pulse oximeter probes. A comparison between finger, nose, ear and forehead probes under conditions of poor perfusion.
The performances of 10 pulse oximeters using finger probes were compared with the same pulse oximeters using alternative probes (eight finger probes, two nose probes and a forehead probe) in poorly perfused patients. All readings were then compared with directly measured arterial blood oxygen saturations. The mean difference (bias, 'accuracy'), standard deviation (precision) and 'drop out' rate for each pulse oximeter combination was determined. ⋯ Some ear probes performed well compared to some finger probes, but the overall performance of probes in other sites compared to finger probes was worse, (p = 0.05). Two of eight ear probes and no nose or forehead probes would be expected to be within 4% of the reference value in 95% of readings. The use of finger probes rather than probes in other sites is recommended in the patient with poor peripheral perfusion.
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The tracheas of 140 adult patients were intubated with either TFX or Portex tracheal tubes. Guide marks were printed at variable distances proximal to the tube cuffs, and during intubation the guide mark was positioned at the level of the vocal cords. The distance between the bevel end of the tube and the carina was determined with a fibreoptic bronchoscope. ⋯ The tip of the tracheal tube approaches the carina by a mean distance of 0.5 cm when the head is moved from the extended position to the neutral position. It is recommended that a guide mark be placed 2.5 cm from the proximal end of the cuff in tubes used for adult males and 2.25 cm in tubes used for adult females. The use of guide marks is a simple, safe and reliable method for correct tracheal tube placement.
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Biography Historical Article
Francis Percival de Caux (1892-1965). An anaesthetist at odds with social convention and the law.
All doctors practice medicine within the confines of what is termed 'acceptable practice'. This acceptable practice is delineated by medical ethics, the actions of one's colleagues, social custom, and the laws of the country. Failure to conform to any or all of these constraints may result in professional ostracism or even loss of liberty. The life and work of Frances Percival de Caux clearly shows these effects in their most damaging manner.
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Randomized Controlled Trial Comparative Study Clinical Trial
Intubation with propofol augmented with intravenous lignocaine.
Sixty patients of ASA grade 1 and aged 18 to 55 years were admitted to a double-blind study. Anaesthesia was induced with propofol 2.5 mg/kg after intravenous pretreatment with lignocaine 1.5 mg/kg or a similar volume of isotonic saline. The quality of subsequent tracheal intubation was graded and the pressor response to tracheal intubation assessed. There were no significant differences between treatment groups.
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Randomized Controlled Trial Comparative Study Clinical Trial
Double-blind comparison of epidural diamorphine and intramuscular morphine after elective caesarean section, with computerised analysis of continuous pulse oximetry.
A randomised, double-blind comparison of the efficacy, duration of action and side effects of two analgesic regimens following elective epidural Caesarean section is described. Patients received epidural diamorphine 3 mg or intramuscular morphine 10 mg in the immediate postoperative period. Time to next analgesia was longer after epidural diamorphine (11.0 hours) compared to intramuscular morphine (6.5 hours) (p less than 0.05). ⋯ However, more patients in the diamorphine group required catheterisation and suffered emetic sequelae, whereas more patients in the morphine group were sedated at 8 hours. Ten patients in each group had continuous pulse oximetry performed overnight after administration of the trial medications. Neither group demonstrated evidence of hypoxia.