To the Editor:—
I read with interest the article “Randomized Study Comparing the ‘Sniffing Position’ with Simple Head Extension for Laryngoscopic View in Elective Surgery Patients” by Adnet et al. 1The authors challenged the sniffing position as the standard head position for laryngoscopic intubation, and they concluded “routine use of the sniffing position appears to provide no significant advantage over simple head extension for tracheal intubation.” I read through the article carefully and found some questions about their study.
First, the degree of glottic exposure depends on the effort during the laryngoscopy. One proposed advantage of the sniffing position is that it reduces the effort required to expose the glottis. 2However, the authors simply compared the glottic exposure between the sniffing position and the head extension position, without noting the effort during the laryngoscopy.
Second, the total number of patients with each IDS score in figure 2 is not equal to the number the authors reported. The sum of the patients in the sniffing position shown on each bar is 228 (128 + 36 + 34 + 10 + 14 + 1 + 3 + 2 = 228), and the sum of the patients in the head extension group is also 228 (111 + 62 + 30 + 13 + 4 + 2 + 2 + 1 + 1 + 1 + 1 = 228). However, the authors claimed that 225 patients were included in the sniffing position group and 231 in the simple head extension group. This mistake should be clarified. Nevertheless, the other conclusion they achieved is thought-provoking:“The sniffing position appears to be advantageous for obese and head extension-limited patients.” Is more laryngoscopy effort required to expose the glottis in these two kinds of patients? The advantage of the sniffing position might lie beneath that question.
Based on these considerations, I am not convinced that the findings of Dr. Adnet et al. could challenge the clinical usefulness of the sniffing position. I believe that the sniffing position is still the optimal position in reducing the effort to expose the glottis during laryngoscopy.
