Developing and validating a tool for measuring the educational environment in clinical anesthesia.

PURPOSE: We aimed to develop a contemporary measure for anesthesia teaching and learning in the operating theatre that was applicable to a variety of training jurisdictions, the Measure for the Anaesthesia Theatre Educational Environment (MATE). METHODS: A systematic review of the literature and modified Delphi approach was used to identify items for content validity. Reliability and exploratory factor analyses were conducted after a pilot survey of trainees to show construct validity, with removal of redundant items. Item domains were identified through a global assessment of factor structure accuracy and relation to real-world constructs. RESULTS: Literature review generated an initial 73-item list. A modified Delphi approach with 24 experts identified 44 relevant items. The pilot survey generated 390 responses. Reliability analysis, exploratory factor analysis, and global assessment refined the measure to 33 items. Four domains were identified according to factor structure: teaching preparation and practice, assessment and feedback, procedures and responsibility, and overall atmosphere. The educational environment was rated by trainees at 74.6 ± 15.6% with excellent internal consistency (Cronbach's α = 0.975). CONCLUSION: The MATE survey tool generated valid and reliable scores when measuring the educational environment in the operating theatre. Further research is required to investigate possible differences between the training countries and age of junior doctors and the associated underlying factors. Other researchers are invited to administer the survey and share results within a central database.

Hemoglobin concentration, total hemoglobin mass and plasma volume in patients: implications for anemia.

In practice, clinicians generally consider anemia (circulating hemoglobin concentration < 120 g.l-1 in non-pregnant females and < 130 g.l-1 in males) as due to impaired hemoglobin synthesis or increased erythrocyte loss or destruction. Rarely is a rise in plasma volume relative to circulating total hemoglobin mass considered as a cause. But does this matter? We explored this issue in patients, measuring hemoglobin concentration, total hemoglobin mass (optimized carbon monoxide rebreathing method) and thereby calculating plasma volume in healthy volunteers, surgical patients, and those with inflammatory bowel disease, chronic liver disease or heart failure. We studied 109 participants. Hemoglobin mass correlated well with its concentration in the healthy, surgical and inflammatory bowel disease groups (r=0.687-0.871, P<0.001). However, they were poorly related in liver disease (r=0.410, P=0.11) and heart failure patients (r=0.312, P=0.16). Here, hemoglobin mass explained little of the variance in its concentration (adjusted R2=0.109 and 0.052; P=0.11 and 0.16), whilst plasma volume did (R2 change 0.724 and 0.805 in heart and liver disease respectively, P<0.0001). Exemplar patients with identical (normal or raised) total hemoglobin masses were diagnosed as profoundly anemic (or not) depending on differences in plasma volume that had not been measured or even considered as a cause. The traditional inference that anemia generally reflects hemoglobin deficiency may be misleading, potentially resulting in inappropriate tests and therapeutic interventions to address 'hemoglobin deficiency' not 'plasma volume excess'. Measurement of total hemoglobin mass and plasma volume is now simple, cheap and safe, and its more routine use is advocated.