B.J. Robinson

Survey of change in practice following simulation-based training in crisis management.

Summary We investigated the long‐term effects on clinical practice of a simulation‐based course in anaesthesia crisis management. A questionnaire was posted to all anaesthetists who had attended a course in the preceding year. The response rate was 69% (66/96). The crisis management course was valued highly by respondents, who perceive a change in practice as a result of the training. This change in practice was not limited to the specific clinical events simulated in the course, but applied to a wide range of events and to routine practice. The high rate of subsequent critical events reported in the survey supports the need for training in this area. This survey suggests that simulation‐based training in crisis management is an effective form of continuing medical education for anaesthetists.

Interdisciplinary team interactions: a qualitative study of perceptions of team function in simulated anaesthesia crises

Objectives  We placed anaesthesia teams into a stressful environment in order to explore interactions between members of different professional groups and to investigate their perspectives on the impact of these interactions on team performance.

Acquisition and maintenance of endoscopic skills: developing an endoscopic dexterity training system for anesthesiologists

The acquisition and maintenance of essential psychomotor skills that are only required sporadically is a significant problem in medical training and practice. It is of particular relevance to anesthesiologists with regard to fibreoptic intubation, a technique that may be under-utilized despite its central role in the management of the difficult airway. Dexterity deficit due to current training models, dexterity decay due to lack of practice, and situational stress related to the clinical environment may combine to impede effective training and confident use of endoscopes in airway management. An educational resource (DexterÔ) has been developed to overcome these problems. Dexter is a non-anatomical, endoscopic dexterity training system designed to encourage practice and help establish and maintain a state of procedural readiness, even if clinical exposure to difficult airway situations is sporadic.

Anaesthetists' management of oxygen pipeline failure: room for improvement*

Oxygen pipeline failure is a rare but potentially catastrophic event which can affect the care of patients throughout an entire hospital. Anaesthetists play a critical role in maintaining patient safety, and should be prepared to support an institution‐wide emergency response if oxygen failure occurs. We tested the preparedness for this through observation of 20 specialist anaesthetists to a standardised simulator scenario of central oxygen supply failure. Responses were documented using multiple approaches to ensure accuracy. All anaesthetists demonstrated safe immediate patient care, but we observed a number of deviations from optimal management, including failure to conserve oxygen supplies and, following restoration of gas supplies, failure to test the composition of the gas supplied from the repaired pipelines. This has implications for patient care at both individual and hospital level. Our results indicate a gap in anaesthesia training which should be addressed, in conjunction with planning for effective hospital‐wide responses to the event of critical resource failure.

Endogeneous opioid modulation of hypercapnic-stimulated respiration in the rat

The role of endogenous opioids in respiratory control in the pentobarbital anaesthetised rat was investigated using a rebreathing technique to generate a progressively increasing hypercapnic stimulus to the respiratory centers following administration of an opioid antagonist or agonist. Respiratory output was measured by intraesophageal pressure (IEP) changes, and a ventilatory equivalent (VEq) was calculated by multiplying IEP by respiratory rate (mmHg.min-1). A non-selective opioid antagonist, naloxone (0.4 mg/kg i.v.), significantly enhanced the slope of the CO2 response curve for VEq (20 +/- 3 mmHg.min-1.%CO2-1) compared with the control (14 +/- 2 mmHg.min-1.%CO2(-1)) (P < 0.05; n = 14). A similar enhancement of the hypercapnic response by naloxone was found in rats anaesthetised with urethane (n = 5). The mu receptor agonist dermorphin (1 mg/kg i.v.) significantly depressed the slope of the CO2 response curve for IEP (-0.01 +/- 0.03) compared with the control (0.10 +/- 0.03) in pentobarbital anaesthetised rats (P < 0.05; n = 5) but had no significant effect on respiratory rate. These results suggest a role of endogenous opioids in the modulation of respiration during hypercapnia.

The effect of hypercapnia and hypoxemia on the cardiovascular responses to isoproterenol

The reason for the increased risk of death with fenoterol and isoproterenol in asthma is unknown but may relate to their cardiovascular effects. Deaths from asthma usually occur outside hospital where hypoxemia, with or without hypercapnia, may exist. Both of these states can influence the cardiovascular system. We investigated whether different gas mixtures modified the cardiovascular effects of isoproterenol.

Detection of problem drinkers in an emergency department using a breathalyser and questionnaire

Over a 2-week period in January 1990 consecutive adult emergency attenders were breathalysed and screened for problem drinking using the WHO screening instrument. Results were compared with a similar study conducted 8 years previously. Of the patients tested, 12.5% had a positive alcohol in 1990 compared with 16% in 1982. Of those with positive alcohol results, the mean blood alcohol equivalent (BAE) concentration was significantly (p=0.0006) lower in 1990 (73.6+/-65.1; mg/100 ml; mean+/-SD) when compared to those levels found in 1982 (136.9+/-102.4 mg/100 ml). There was also significant reductions in 1990 of positive breath alcohol attenders both from road traffic accidents (p<0.03), and from head injuries (p<0.005) compared to 1982. In 1990 the questionnaire was positive in 23% of attendees. These studies suggest a trend towards less alcohol misuse in emergency department patients, but nevertheless indicate high rates of problem drinking. It is suggested that alcohol breathalysers be available in emergency departments to assist the detection of alcohol misusers and predict alcohol-associated medical problems.

Autonomic responses to carbohydrate ingestion and head-up tilt in elderly subjects with orthostatic hypotension

To investigate the role of glucose and insulin in the development of hypotension following glucose ingestion in elderly subjects with orthostatic hypotension, the autonomic responses to glucose and xylose ingestion were studied in five elderly subjects with age related orthostatic hypotension (without autonomic failure), five elderly control subjects and three elderly subjects with evidence of autonomic failure. Heart rate, blood pressure, plasma noradrenaline and plasma arginine vasopressin responses to glucose ingestion and to xylose ingestion were investigated. All subjects were supine for 90 min following ingestion of each carbohydrate and were then tilted 45° head-up for 10 min. Blood pressure was maintained in elderly control subjects following ingestion of both carbohydrates and during tilting. The elderly group with orthostatic hypotension, while supine had a fall in systolic blood pressure 60–90 min following both glucose and xylose ingestion. Diastolic blood pressure was lowered 60–90 min after glucose but not xylose. During tilting, blood pressure fell by similar levels following both carbohydrate ingestions; plasma noradrenaline levels after 2 min and plasma arginine vasopressin levels after 10 min tilting were significantly less following glucose ingestion compared to xylose ingestion. The autonomic failure group while supine had a fall in systolic blood pressure 60–90 min following both glucose and xylose ingestion. Diastolic blood pressure was lowered 60–90 min after glucose but not xylose. During tilting, blood pressure fell by similar levels following both carbohydrate ingestion. Plasma noradrenaline and arginine vasopressin levels were unchanged after ingestion of either carbohydrate, and during tilting. These results suggest that hypotension following glucose ingestion in elderly subjects with orthostatic hypotension, but without efferent autonomic failure may be due, in part, to impaired afferent or central baroreceptor reflexes.To investigate the role of glucose and insulin in the development of hypotension following glucose ingestion in elderly subjects with orthostatic hypotension, the autonomic responses to glucose and xylose ingestion were studied in five elderly subjects with age related orthostatic hypotension (without autonomic failure), five elderly control subjects and three elderly subjects with evidence of autonomic failure. Heart rate, blood pressure, plasma noradrenaline and plasma arginine vasopressin responses to glucose ingestion and to xylose ingestion were investigated. All subjects were supine for 90 min following ingestion of each carbohydrate and were then tilted 45° head-up for 10 min. Blood pressure was maintained in elderly control subjects following ingestion of both carbohydrates and during tilting. The elderly group with orthostatic hypotension, while supine had a fall in systolic blood pressure 60–90 min following both glucose and xylose ingestion. Diastolic blood pressure was lowered 60–90 min after glucose but not xylose. During tilting, blood pressure fell by similar levels following both carbohydrate ingestions; plasma noradrenaline levels after 2 min and plasma arginine vasopressin levels after 10 min tilting were significantly less following glucose ingestion compared to xylose ingestion. The autonomic failure group while supine had a fall in systolic blood pressure 60–90 min following both glucose and xylose ingestion. Diastolic blood pressure was lowered 60–90 min after glucose but not xylose. During tilting, blood pressure fell by similar levels following both carbohydrate ingestion. Plasma noradrenaline and arginine vasopressin levels were unchanged after ingestion of either carbohydrate, and during tilting. These results suggest that hypotension following glucose ingestion in elderly subjects with orthostatic hypotension, but without efferent autonomic failure may be due, in part, to impaired afferent or central baroreceptor reflexes.

Familial distal dysautonomia.

A patient is described who presented with painful feet on exercise. He had no evidence of peripheral vascular disease but did have anhidrosis and failure of vasodilatation in the hands and feet suggesting peripheral dysautonomia. Examination of his mother and a cousin and clinical histories of blood relatives suggested that his problem was a severe presentation of a familial distal dysautonomia. In other family members this was represented by dry hands and feet and variable vasomotor symptoms. This condition appeared to be autosomal dominant.