[Assessment of agreement between anesthesiologists' location of anatomical landmarks]

The main objective of this study was to evaluate agreement between anesthesiologists' location of specific anatomical landmarks in regional anesthesia.

We administered an anonymous written questionnaire asking for the location of the T5 and T10 dermatomes, Tuffier's line (L3-L4 space), and the T7-T8 and C6-C7 spaces on an anatomical drawing. We asked about each anesthesiologist's number of years of experience and type of block most commonly performed and in what type of surgery, number of blocks performed per year, whether or not levels of sensory and motor blocks were assessed, and whether training had been received. Relative frequencies were then calculated. The relationships between years of experience and number of blocks performed and number of correct identifications of anatomical points were analyzed using the chi2 test.

We studied 100 doctors (66 residents and 24 staff anesthesiologists). The landmark for which agreement was highest was T10 (91.8%); agreement was lowest for T5 (38.1%). Forty-five percent of anesthesiologists performed between 100 and 250 neuraxial blocks per year. The most commonly performed procedure was a lumbar block (98% of the anesthesiologists). Level of sensory block was evaluated by 95% of the respondents and level of motor block by 83%. Response to heat and cold was used by 94.8%; the Bromage scale was used by 81%. The number of years of experience and the number of correctly located points appeared to be unrelated (P=.76). Nor was there a correlation between the number of blocks performed and number of correctly located points (P=.2).

T10 was the landmark correctly identified by the largest number of respondents; T5 was correctly identified by the fewest respondents, with answers differing by as much as 4 dermatomes.