Both the intubating laryngeal mask airway Fastrach and the Trachlight lightwand attenuate the hemodynamic stress response to tracheal intubation compared with the Macintosh laryngoscope in hypertensive, but not in normotensive, anesthetized paralyzed patients.

Cerebellar Purkinje cells (PC) are particularly vulnerable to ischemic injury and excitotoxicity, although the molecular basis of this sensitivity remains unclear. We tested the hypothesis that ischemia causes rapid down‐regulation of GABAA receptors in cerebellar PC, thereby increasing susceptibility to excitotoxicity. Oxygen‐glucose deprivation (OGD) caused a decline in functional GABAA receptors, within the first hour of re‐oxygenation. Decreased amplitude of miniature inhibitory post‐synaptic potentials confirmed that OGD caused a significant decrease in functional synaptic GABAA receptors and quantitative Western blot analysis demonstrated the loss of GABAA receptor current was associated with a decline in total receptor protein. Interestingly, the potent neuroprotectant allopregnanolone (ALLO) prevented the decline in GABAA receptor current and protein. Consistent with our in vitro data, global ischemia in mice caused a significant decline in total cerebellar GABAA receptor protein and PC specific immunoreactivity. Moreover, ALLO provided strong protection of PC and prevented ischemia‐induced decline in GABAA receptor protein. Our findings indicate that ischemia causes a rapid and sustained loss of GABAA receptors in PC, whereas ALLO prevents the decline in GABAA receptors and protects against ischemia‐induced damage. Thus, interventions which prevent ischemia‐induced decline in GABAA receptors may represent a novel neuroprotective strategy.

We tested the hypothesis that haemodynamic changes to intubation and postoperative pharyngolaryngeal morbidity are similar for blind intubating laryngeal mask (ILM)-guided compared with laryngoscope-guided tracheal intubation in adults with normal airways. We also compared intubation success rates and airway complications. One-hundred and fifty paralysed, anaesthetized adult patients undergoing elective surgery were randomly assigned to one of three equal-sized groups: 1. blind intubation via the ILM using a straight, silicone tube; 2. intubation with a Macintosh laryngoscope using a straight silicone tube and 3. intubation with a Macintosh laryngoscope using a polyvinyl chloride tube (controls). A standard sequence of adjusting manoeuvres was followed if intubation was difficult. The number of adjusting manoeuvres and intubation attempts, time to intubation, intubation success rate (first attempt and within 3 min), haemodynamic changes (pre-induction, post-induction, post-intubation), oesophageal intubation, mucosal trauma (blood detected), hypoxia (SpO 2 <95%) and postoperative pharyngolaryngeal morbidity (double-blinded) were documented. Time to successful intubation was longer (57 vs 35s), and more intubation attempts were required in the ILM group (P<0.0001). The intubation success rate was 100% (all first attempt) for the laryngoscope groups and 94% (56% first attempt) for the ILM group. There were no significant differences in heart rate or blood pressure among groups. Oesophageal intubation (26 v 0%) and mucosal trauma (19 v 2%) were more common in the ILM group. Hypoxia and postoperative pharyngolaryngeal morbidity were similar among groups. Blind intubation through the ILM offers no advantages over the Macintosh laryngoscope for adult patients requiring intubation for elective surgery with normal airways, but it is a feasible alternative.

The pharyngeal and tracheal placement phases of nasotracheal intubation require fewer attempts with a silicone-based wire-reinforced tracheal tube with a hemispherical bevel than with a polyvinyl chloride-based precurved tracheal tube with a conventional diagonal bevel, but the glottic placement phase requires more attempts. Nasal morbidity is less common with the silicone tracheal tube.

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Background Several algorithms for localizing accessory pathways (APs) are based on the delta wave morphology, R/S ratio, and QRS polarity. However, they are somewhat complicated, and an accurate determination of the delta wave morphology is occasionally difficult. The aims of this study were to develop a simple algorithm for localizing APs using only the R/S ratio, and to test the accuracy of the algorithm prospectively. Methods We studied 142 patients with a single anterogradely conducting AP on a 12‐lead ECG. R/S ratios were analyzed in leads V1, V2, and aVF (R/S‐V1, R/S‐V2, and R/S‐aVF). AP locations were divided into five regions based on fluoroscopic anatomy. Results A new algorithm was developed by correlating R/S‐V1, R/S‐V2, and R/S‐aVF with successful ablation sites in 88 initial consecutive patients. All 55 patients with left free wall APs showed R/S‐V1 ≥0.5, and 47 (98%) of 48 patients with left anterior or lateral APs showed R/S‐aVF ≥1. In contrast, all seven patients with left posterolateral or posterior APs showed R/S‐aVF <1. All nine patients with right‐and‐left midseptal or posteroseptal APs showed R/S‐V1 <0.5 and R/S‐V2 ≥0.5. Of 12 patients with right anterior, lateral or anteroseptal APs, 10 (83%) showed R/S‐V1 <0.5, R/S‐V2 <0.5 and R/S‐aVF ≥1. Finally, nine (75%) of 12 patients with right posterolateral or posterior APs showed R/S‐V1 <0.5, R/S‐V2 <0.5, and R/S‐aVF <1. Then this algorithm was tested prospectively in 54 patients. Overall, the sensitivity was 94%, and the specificity was 98%. Conclusions This ECG algorithm provides a simple and accurate way to identify the AP localization.

Nitrous oxide and sevoflurane suppress the responses to LMA insertion in a linear and additive fashion in children.

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