Anaesthesia
-
In patients with highly contagious diseases that are spread by respiratory droplets or air-borne particles, the use of high-flow oxygen may carry a significant risk of nosocomial transmission. We tested a new oxygen delivery device designed to address these problems by simulating 108 patients with sepsis and respiratory failure. The device being tested consisted of an airtight mask, a bacterial and viral filter, a T-shaped reservoir (50 and 100 ml) and oxygen delivery tubing connected directly to the mask. ⋯ The 50-ml reservoir, when compared with the 100-ml reservoir, was associated with reduced carbon dioxide rebreathing (mean (SD) inspired fractional carbon dioxide concentration 2.5 (1.0) vs 3.0 (1.1), respectively, p = 0.009) and reduced inspiratory resistive work of breathing (mean (SD) 1.0 (0.6) J.l(-1) vs 1.2 (0.5) J.l(-1), respectively, p = 0.028). However, rebreathing and work of breathing were relatively high if a high respiratory rate was simulated. We conclude that the novel oxygen device we describe, equipped with the 50-ml T-shaped reservoir, is suitable for potentially infectious patients with type-1 respiratory failure but without marked tachypnoea.
-
The aim of this study was to predict the optimal depth for insertion of a left-sided central venous catheter in children. Using 3D chest computed tomography angiography, we measured the distance from a point where the internal jugular vein is at the superior border of the clavicle, and from a point where the subclavian vein is inferior to the anterior border of the clavicle, to the junction of the superior vena cava and the right atrium in 257 children. ⋯ Simple formulae for the depth of a central venous catheter via the left internal jugular vein (0.07 × height (cm)) and the left subclavian vein (0.08 × height (cm)) were developed to predict placement of the central venous catheter tip at the junction of the superior vena cava with the right atrium. Using these fomulae, the proportion of catheter tips predicted to be correctly located was 98.5% (95% CI 96.8-100%) and 94.0% (95% CI 90.8-97.3%), respectively.
-
Letter Case Reports
Bispectral index changes during generalised tonic-clonic seizures.
-
Debate continues over the dose and methods of administration of oxytocin for the prevention of haemorrhage during caesarean section. We surveyed 206 lead obstetric anaesthetists in the UK to determine standard practice in their unit as well as any differences in practice for high-risk cases. There were 150 responses (72.9% response rate). ⋯ Forty (26.8%) respondents give a different oxytocin regimen following caesarean section in patients with severe pre-eclampsia, 72 (48.3%) in those with cardiac disease of New York Heart Association class 1-2, and 100 (66.7%) with class 3-4. In conclusion, there is a trend towards the use of lower doses of oxytocin in caesarean section, but there are still wide variations in detail. We suggest that there is a need for a national protocol to standardise oxytocin administration.