The study was a cross-sectional survey. The survey was developed and validated by consensus by a group of anesthesiologists and clinical epidemiologists, and tested thereafter in a small group of anesthesiologists. It was printed on both sides of a sheet of paper, and attached to the documents delivered to each of the 825 anesthesiologists subscribed to the Annual Updated Course organized by the Sociedad Mexicana de Anestesiologia in 2000. This course, traditionally carried out in Mexico City, was selected due to the fact that it is the major national course of anesthesia, and therefore colleagues from all over the country attend the course. This gives the course a national representation. Voluntary participation was mentioned verbally at the moment the printed survey was provided to the anesthesiologists. Negation to answer the survey was not penalized in any form.
The survey included the following four sections:
Section 1. General information
1. Your current maximal specialty training is: anesthesiologist, anesthesiologist with subspecialty training, or anesthesiology resident
2. Have you been practicing anesthesia for <5, 5 to 10, or >10 years?
3. Have you been working at a public, private or both types of health services?
4. Are your anesthetic procedures performed in pediatric, adult, or mixed patients? If mixed patients was selected, then the proportion representing the pediatric patients was asked (<25, 25 to 50, 50 to 75 or >75%).
5. Are your anesthetic procedures performed on ambulatory, hospitalized, or mixed patients? If a mixed setting was selected, then the proportion representing the pediatric patients was asked (<25, 25 to 50, 50 to 75 or >75%).
Section 2. The availability of guidelines at work
6. Do you have fasting guidelines at your work? If so, how long have they been available at you private or public health service?
Section 3. Knowledge of guidelines
7. Have you read the guidelines for fasting periods elaborated by the American Society of Anesthesia (ASA) Task Force on Preoperative Fasting published in 1999?
8. Have you read the guidelines for preoperative fasting periods published by the Sociedad Mexicana de Anestesiología in 1999? (This question in relation to non-existent guidelines was included in order to evaluate whether the anesthesiologists were answering automatically positive).
Section 4. Clinical practices. For this section, we considered a clear liquid to be any aqueous solution which is liquid at 37°C [3], non clear fluids to be suspensions and emulsions, breast milk whether it was directly provided by the mother or obtained from her and thereafter provided by means of a nursing bottle, and solid food to be any kind of meat.
9. A list of eight drinks was provided and anesthesiologists had to answer whether they were clear liquids or not. The following drinks were included: clear water, industrialized fruit juice, natural fruit juice, black coffee, breast milk and infant formula, milk-based jelly, concentrated industrialized fruit juice, and liquid food supplement (e.g. Ensure®)
10. What is your attitude for a male patient, 2 yr. old undergoing surgical repair of a hiatal hernia who ingested breast milk 1 h before surgery: to avoid the surgery, to delay the surgery for 2, 3 or 6 to 8 h, or to continue with the surgical plan?
11. What is your attitude for a patient 62 yr. old receiving ranitidine and cisapride, and undergoing surgical repair of hiatal hernia: to avoid the surgery, to modify the dose of ranitidine and cisapride, no modification in dosage and continuation of surgical plan, or you do not know?
12. What duration of pre-operative fasting using breast milk or infant formula do you recommend for patients age <6 mo., 6 mo. to 3 yr., or children >3 yr. undergoing a surgical procedure?
13. What duration of pre-operative fasting for using clear liquids do you recommend for patients aged <6 mo., 6 mo. to 3 yr., children >3 yr., adolescents and adults, or old patients undergoing a surgical procedure?
14. What duration of pre-operative fasting for solids do you recommend for patients aged <6 mo., 6 mo. to 3 yr., children >3 yr., adolescents and adults, or old patients undergoing a surgical procedure?
Invitation to return the survey was performed during the resting periods of the course. Because the course did not include any topic on fasting, no follow-up questionnaire was performed. The response rate was 31.4%, and data were summarized by means of descriptive statistics as number and proportions (%) with the corresponding 95% confidence of intervals (CI95%), the two latter computed from respondents for each question. When answers were analyzed as a set, comparisons between children and adults were performed by means of the x2 test at a significant limit of p < 0.05, and CI95% were not computed.