1. Hypotension during induction of anaesthesia is neither a reliable nor a useful quality measure for comparison of anaesthetists’ performance 
R.H. Epstein, F. Dexter, E.S. Schwenk 
British Journal of Anaesthesia 
Volume 119, Issue 1, Pages (July 2017)
DOI: /bja/aex153
Copyright © 2017 The Author(s) Terms and Conditions

2. Fig 1
Caseload and percentage of eligible cases and supervising anaesthetists evaluable for hypotension peer comparison. The total caseload (blue line) is presented for calendar years 2006–15. The percentages of eligible cases (green bars) represent the fraction of the total caseload where patients received care as an inpatient after surgery, had an ASA physical status (ASA PS) of ≥III, were ≥50 yr of age, and underwent surgical procedures lasting >60 min. The percentages of evaluable anesthesiologists (orange bars) represent the fraction of anaesthetists who supervised ≥100 total cases who also supervised at least 100 evaluable cases.
British Journal of Anaesthesia  , DOI: ( /bja/aex153)
Copyright © 2017 The Author(s) Terms and Conditions

3. Fig 2
Contribution by each anaesthetist (coloured columns) with 99% confidence intervals (CIs) to the total amount of area under the curve for mean arterial pressure (MAP) <65 mm Hg (AUC65; red line). The error bars show 99% CIs computed using the method of batch means (see Methods). Data were six 2 month intervals between November 1, 2015 and October 31, The mean value of the AUC65 (blue line) was 44.8 (sem 1.0) mm Hg min, representing the pooled mean of all cases during the year. Anaesthetists plotted performed at least six cases in each of the 2 month batches and a minimum of 100 cases. The yellow columns represent two outliers for more hypotension (lower limit of the 99% CI not overlapping the pooled mean AUC65), and the four green columns those with better performance than the pooled mean AUC65.
British Journal of Anaesthesia  , DOI: ( /bja/aex153)
Copyright © 2017 The Author(s) Terms and Conditions

4. Fig 3
Linear rank regression (dotted purple line) and ordinary least-squares linear regression (black line) between the average propofol dose in milligrams per kilogram administered from induction to surgical incision and the average area under the curve (AUC) for mean arterial pressure (MAP) <65 mm Hg in the operating theatre until surgical incision. Each circle represents a single anaesthetist who supervised at least 100 eligible cases between November 1, 2015 and October 31, The yellow and green circles represent anaesthetists with more or less hypotension than the pooled mean AUC, respectively (see Fig. 2). Kendall’s τB = −0.058 (P=0.62), indicating no relationship between the dose of propofol in milligrams per kilogram and the hypotension AUC. Despite the visual appearance of a negative slope (i.e. less hypotension with more propofol), this scattergram is not significantly different from random.
British Journal of Anaesthesia  , DOI: ( /bja/aex153)
Copyright © 2017 The Author(s) Terms and Conditions

5. Fig 4
Linear rank regression (dotted purple line) and ordinary linear regression (black line) between the average propofol dose in milligrams administered from induction to surgical incision and the average area under the curve (AUC) for mean arterial pressure (MAP) <65 mm Hg in the operating theatre until surgical incision. Averages were computed only among cases where propofol was administered. Each point represents a single anaesthetist who supervised at least 100 eligible cases between November 1, 2015 and October 31, The yellow and green circles represent anaesthetists with more or less hypotension, respectively, than the pooled mean AUC (see Fig. 2). Kendall’s τB=0.064 (P=0.58), indicating no significant relationship between the dose of propofol in milligrams and the hypotension AUC. Note that the anaesthetist with the greatest amount of hypotension administered the smallest average dose of propofol. Despite the visual appearance of a negative slope (i.e. less hypotension with more propofol), this scattergram is not significantly different from random.
British Journal of Anaesthesia  , DOI: ( /bja/aex153)
Copyright © 2017 The Author(s) Terms and Conditions

6. Fig 5
Linear rank regression (dotted purple line) and ordinary linear regression (black line) between the average phenylephrine dose in micrograms administered from induction to surgical incision and the average area under the curve (AUC) for mean arterial pressure (MAP) <65 mm Hg in the operating theatre until surgical incision. For cases where no phenylephrine was administered, a dose of 0 μg was applied. Each point represents a single anaesthetist who supervised at least eligible 100 cases between November 1, 2015 and October 31, The yellow and green circles represent anaesthetists with more or less hypotension, respectively, than the pooled mean AUC (see Fig. 2). Kendall’s τB=0.22 (P=0.053), indicating a modest relationship trend between the hypotension AUC and the dose of phenylephrine. Anaesthetists with more hypotension tended to administer more phenylephrine than those with less hypotension.
British Journal of Anaesthesia  , DOI: ( /bja/aex153)
Copyright © 2017 The Author(s) Terms and Conditions

7. Fig 6
Linear rank regression (dotted purple line) and ordinary linear regression (black line) between the average ephedrine dose in mg administered from induction through surgical incision and the average area under the curve (AUC) for mean arterial pressure (MAP) <65 mm Hg in the operating theatre until surgical incision. For cases where no ephedrine was administered, a dose of 0 mg was applied. Each point represents a single anaesthetist who supervised at least 100 eligible cases between November 1, 2015 and October 31, The yellow and green circles represent anaesthetists with more or less hypotension, respectively, than the pooled mean AUC (see Fig. 2). The Kendall’s τB = −0.084 (P=0.47), indicating no relationship between the hypotension AUC and the dose of ephedrine.
British Journal of Anaesthesia  , DOI: ( /bja/aex153)
Copyright © 2017 The Author(s) Terms and Conditions