To the Editor:
I read with interest the recent survey of the practice policies of anesthesiologists regarding the intake of clear liquids and a light breakfast by adult patients presenting for elective outpatient surgery (1). However, I was puzzled by the authors’ statement: “…coffee and tea are included as clear liquids…” (1).
Shevde and Trivedi considered black coffee a clear liquid in their study of the effects of clear liquids on gastric volume and pH (2). They stated: “We have used the word ‘clear’ to exclude liquids with suspensions (such as juice with pulp) or those that may form solids in the stomach such as milk” (2). Shevde and Trivedi evidently did not consider coffee with milk to be a clear liquid.
An obvious fact is that coffee is not a clear liquid. Indeed, a test of several types of coffee contained in clear cups demonstrated the opacity of the liquids both before and after the administration of sugar and milk or cream.
I propose that authors should state explicitly if they mean that, in their judgment, coffee whether with milk or cream or black may be safely included with plain tea and other obviously clear liquids as a beverage that patients may safely consume before elective outpatient surgery. However, that would still not make coffee a clear liquid.
My reason for raising this apparently trivial point is that, as an anesthesiologist who works at several facilities dealing with outpatients, this issue has come up more than once, and it has been a source of confusion to health care professionals and patients.
Mitchel B. Sosis MD, PhD
1. Pandit SK, Loberg KW, Pandit UA. Toast and tea before elective surgery? A national survey of current practice. Anesth Analg 2000; 90: 1348–51.
2. Shevde K, Trivedi N. Effects of clear liquids on gastric volume and pH in healthy volunteers. Anesth Analg 1991; 72: 528–31.