British journal of anaesthesia
-
ScanNavTMAnatomy Peripheral Nerve Block (ScanNav™) is an artificial intelligence (AI)-based device that produces a colour overlay on real-time B-mode ultrasound to highlight key anatomical structures for regional anaesthesia. This study compares consistency of identification of sono-anatomical structures between expert ultrasonographers and ScanNav™. ⋯ Human experts and the AI system both showed the same pattern of agreement in sono-anatomical structure identification. The clinical significance of the differences presented must be explored; however the perception that human expert opinion is uniform must be challenged. Elements of this assessment framework could be used for other devices to allow consistent evaluations that inform clinical training and practice. Anaesthetists should be actively engaged in the development and adoption of new AI technology.
-
Sensory disconnection is a key feature of sleep and anaesthesia. We have proposed that predictive coding offers a framework for understanding the mechanisms of disconnection. Low doses of ketamine that do not induce disconnection should thus diminish predictive coding, but not abolish it. ⋯ NCT03284307.
-
Anaemic cardiac surgery patients are at greater risk of intraoperative red blood cell transfusion. This study questions the application of the World Health Organization population-based anaemia thresholds (haemoglobin <120 g L-1 in non-pregnant females and <130 g L-1 in males) as appropriate preoperative optimisation targets for cardiac surgery. ⋯ The World Health Organization female anaemia threshold of haemoglobin <120 g L-1 disproportionately disadvantages female cardiac surgery patients. A preoperative haemoglobin concentration ≥130 g L-1 in adult cardiac surgery patients would minimise their overall probability of intraoperative red blood cell transfusion to <15%.
-
Editorial Comment
The art of chasing numbers in titration of anaesthetic dose.
There is no difference in between-patient variability of concentrations when comparing propofol and sevoflurane titrated to a bispectral index of 40-60. There is about a 300% variation in hypnotic concentration between the bottom 5% and top 5% of the population. Anaesthesia titration cannot be based solely on measured or estimated drug concentrations.
-
Editorial Comment
Achieving a preoperative haemoglobin above 130 g L-1 may be more important in female than in male patients before cardiac surgery.
Sex-specific preoperative haemoglobin levels and the need for perioperative red cell transfusion in men and women are still debated. Cavalli and colleagues examined the appropriateness of World Health Organization (WHO) anaemia thresholds (haemoglobin <130 g L-1 for males and <120 g L-1 for females) in a retrospective cohort analysis of >6000 adult patients undergoing cardiac surgery with cardiopulmonary bypass. The authors concluded that the WHO anaemia threshold disproportionately disadvantages female cardiac surgery patients, and a preoperative haemoglobin level of at least 130 g L-1 should be targeted in all cardiac surgical patients regardless of sex.