Anaesthesia
-
Controlled Clinical Trial
High-flow humidified nasal oxygenation vs. standard face mask oxygenation.
Ten healthy volunteers received oxygen for 1 min, 2 min and 3 min at 10 l.min-1 via a face mask, or humidified oxygen at 60 l.min-1 via nasal prongs (OptiflowTM ) with the mouth closed and with the mouth open. The mean (SD) end-tidal oxygen partial pressure after 3 min face mask and Optiflow oxygenation, with mouth closed and open, were: 88.5 (6.2) kPa; 85.6 (6.4) kPa and 48.7 (26.4) kPa, respectively, p = 0.001. The equivalent mean (SD) transcutaneous oxygen partial pressures were: 34.6 (5.4) kPa; 36.4 (6.5) kPa and 25.5 (15.7) kPa, respectively, p = 0.03. High-flow humidified nasal oxygenation for 3 min with the mouth closed was as effective as 3 min face mask oxygenation.
-
The unique pharmacology of remifentanil makes it a popular intra-operative analgesic. Short-acting opioids like remifentanil have been associated with acute opioid tolerance and/or opioid-induced hyperalgesia, two phenomena which have different mechanisms and are pharmacologically distinct. Clinical studies show heterogeneity of remifentanil infusion regimens, durations of infusion, maintenance of anaesthesia, cumulative dose of remifentanil and pain measures, which makes it difficult to draw conclusions about the incidence of acute tolerance or hyperalgesia. ⋯ Infusion rates greater than 0.2 μg.kg-1 .min-1 are characterised by lower mechanical/pressure/cold/pain thresholds, which suggests hyperalgesia. The use of concurrent multimodal analgesia, especially N-methyl-D-aspartate receptor antagonists, may be an effective preventive strategy. The clinical significance and long-term consequences of these entities is still uncertain.
-
Randomized Controlled Trial Comparative Study
A prospective randomised study of a rigid video-stylet vs. conventional lightwand intubation in cervical spine-immobilised patients.
Compared with a lightwand which is used blind, Optiscope™ , a rigid video-stylet, can provide direct imaging of airway structures, potentially offering improved conditions in cervical spine-immobilised patients. We randomly assigned 168 patients who required cervical immobilisation during tracheal intubation to use of the Optiscope or the lightwand. ⋯ The incidence of postoperative airway complications was similar in the two groups. The devices were equivalent with respect to initial intubation success rate but the Optiscope yielded slightly longer intubating times.
-
Multicenter Study
A national survey of practical airway training in UK anaesthetic departments. Time for a national policy?
The Fourth National Audit Project (NAP4) recommended airway training for trainee and trained anaesthetists. As the skills required for management of airway emergencies differ from routine skills and these events are rare, practical training is likely to require training workshops. In 2013, we surveyed all UK National Health Service hospitals to examine the current practices regarding airway training workshops. ⋯ Reported barriers to training include lack of time and departmental or individual interest. Workshop-based airway training is variable in provision, frequency and content, and is often not prioritised by departments or individual trainers. It could be useful if guidance on workshop organisation, frequency and content was considered nationally.
-
Observational Study
Changes in qualitative and quantitative ultrasound assessment of the gastric antrum before and after elective caesarean section in term pregnant women: a prospective cohort study.
Ultrasound measurement of the antral cross-sectional area allows a quantitative estimate of gastric contents in non-pregnant adults, but this relationship may be affected by compression of the stomach exerted by the gravid uterus during pregnancy. This study aimed to assess differences in quantitative (Perlas score) and qualitative (antral cross-sectional area) ultrasound assessments of the gastric antrum performed immediately before and after caesarean section. Forty-three women having elective caesarean section performed under spinal anaesthesia were studied in the semirecumbent and semirecumbent-right lateral positions. ⋯ The distance between the skin and the antrum, and the aorta and the antrum, decreased significantly in both positions after surgery. We suggest that our results indicate that stomach contents remain largely unchanged in women having elective caesarean section, but antral cross-sectional area decreases, especially in the semirecumbent position, related to a change in the position of the stomach within the abdomen. This implies that the relationship of antral cross-sectional area to volume of stomach contents, which has been determined for non-pregnant subjects, may not apply in term pregnant women.