Anaesthesia
-
Randomized Controlled Trial
The effect of magnesium sulphate infusion on the incidence and severity of emergence agitation in children undergoing adenotonsillectomy using sevoflurane anaesthesia.
This randomised, controlled, double-blind study investigated the effects of intra-operative magnesium sulphate administration on the incidence of emergence agitation in children undergoing adenotonsillectomy using sevoflurane anaesthesia. Seventy children were randomly allocated to receive a 30 mg.kg(-1) bolus of intravenous magnesium sulphate after induction of anaesthesia followed by a continuous infusion of 10 mg.kg(-1).h(-1) or an equal volume of saline 0.9%. All children received titrated sevoflurane anaesthesia adjusted to maintain haemodynamic stability. ⋯ Emergence agitation was more common in the control group than in the magnesium group (23 (72%) and 12 (36%), respectively (p = 0.004)), with a relative risk of 0.51 (95% CI 0.31-0.84), an absolute risk reduction of 0.35 (95% CI 0.10-0.54), and number needed to treat of 3 (95% CI 2-9). Postoperative pain scores were comparable in the two groups. Magnesium sulphate reduces the incidence and severity of emergence agitation in children undergoing adenotonsillectomy using sevoflurane anaesthesia and is not associated with increased postoperative side-effects or delayed recovery.
-
Randomized Controlled Trial
Virtual airway simulation to improve dexterity among novices performing fibreoptic intubation.
We developed a virtual reality software application (iLarynx) using built-in accelerometer properties of the iPhone(®) or iPad(®) (Apple Inc., Cupertino, CA, USA) that mimics hand movements for the performance of fibreoptic skills. Twenty novice medical students were randomly assigned to virtual airway training with the iLarynx software or no additional training. ⋯ Cusum analysis demonstrated continued group improvement in the iLarynx, but not in the standard training group. Virtual airway simulation using freely available software on a smartphone/tablet device improves dexterity among novices performing upper airway endoscopy.
-
Randomized Controlled Trial Comparative Study
Comparison of the Baska(®) mask with the single-use laryngeal mask airway in low-risk female patients undergoing ambulatory surgery.
We compared the Baska(®) mask with the single-use classic laryngeal mask airway (cLMA) in 150 females at low risk for difficult tracheal intubation in a randomised, controlled clinical trial. We found that median (IQR [range]) seal pressure was significantly higher with the Baska mask compared with the cLMA (40 (34-40 [16-40]) vs 22 (18-25 [14-40]) cmH2O, respectively, p < 0.001), indicating a better seal. In contrast, the first time success rate for insertion of the Baska mask was lower than that seen with the cLMA (52/71 (73%) vs 77/99 (98%), respectively, p < 0.001). ⋯ The Baska mask proved more difficult to insert, requiring more insertion attempts, taking longer to insert and had higher median (IQR [range]) insertion difficulty scores (1.6 (0.8-2.2 [0.1-5.6]) vs 0.5 (0.3-1.4 [0.1-4.0]), respectively, p < 0.001). There was also an increased rate of minor blood staining of the Baska mask after removal, but there were no differences in other complication rates, such as laryngospasm, or in the severity of throat discomfort. In conclusion, in clinical situations where the seal with the glottic aperture takes priority over ease of insertion, the Baska mask may provide a useful alternative to the cLMA.
-
Comparative Study
The ability of bispectral index to detect intra-operative wakefulness during isoflurane/air anaesthesia, compared with the isolated forearm technique.
Clinical signs are unreliable for guiding anaesthetic administration and it is suggested that using the bispectral index can improve anaesthetic delivery. In the current study, isoflurane administration was guided to a bispectral index range of 55-60. Intra-operative responsiveness, as assessed by the isolated forearm technique, was compared with whether the bispectral index predicted/identified a patient's appropriate hand movements in response to commands. ⋯ For patients who responded more than once during surgery, the bispectral index value associated with a response was not constant. No patient had recall for surgery or the taped commands, and only one could remember dreaming (a good dream). Titrating isoflurane to target a bispectral index range of 55-60 may result in an unacceptable number of patients who are conscious during surgery (albeit without recall).
-
This observational study assessed the frequency and risk factors of dental damage after classic direct laryngoscopy for tracheal intubation in 536 adult patients. The patients' sex, age, height, weight, dental condition, dental mobility, Mallampati class, interincisor gap, thyromental distance, neck circumference, and head and neck extension were recorded. From anaesthesia records, the difficulty of intubation, the number of attempts, type of neuromuscular blocking agent used and duration of anaesthesia were recorded. ⋯ Enamel fracture was the commonest injury. In tooth number 21, the interincisor gap (OR 2.5 (95% CI 1.0-5.9)) and in tooth number 22, the number of intubation attempts (OR 5.3 (95% CI 1.3-22.0)) were considered a risk factor for dental injury. Conventional direct laryngoscopy is associated with a strikingly high incidence of dental damage, although specific risk factors remain unclear.