| JOURNAL HOME | CME HOME | THIS MONTH | PAST ISSUES | ETOC | COLLECTIONS |
| AUTHORS | REVIEWERS | EDITORIAL BOARD | FEEDBACK | RSS | HELP |
| ||||||||||||||
| ||||||||||||||
|
|
|
|
||||||||||||
|
||||||||||||||
Department of Anesthesiology Campus Eye Group Trenton, New Jersey
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.
References
Department of Anesthesiology University of Michigan Health Care System Ann Arbor, MI 48109
In Response:
We greatly appreciate Dr. Sosis’s interest in our paper (1). This also gives us an opportunity to clarify the prevalent ambiguity about types of "clear" liquid that are allowed 2–3 h before elective surgery. Dr. Sosis has asked a very relevant question: is coffee (or tea) a clear liquid? According to the Webster’s dictionary, the word "clear" (adjective) has many meanings. Some of these are, bright, luminous, obvious, plain, cloudless, free from blemishes, free from impurity, transparent, and free from doubt.
Dr. Sosis has interpreted "clear" as "transparent" or colorless, something that we can see through, e.g., water, transparent glass, a noncola drink (such as 7-Up). According to this interpretation, black coffee, plain tea, pulp-free orange juice, some types of apple juice, and cola drinks may not be accepted as "clear" liquid. However, if one takes the other meaning of "clear," that is, free from blemishes or particulates, then all of the above liquids are actually "clear." Milk, however, is not a clear liquid, because it forms curd (solid particulate material) as soon as it reaches the stomach. So, adding milk or cream to coffee makes it "unclear."
We have taken an informal poll among the members of our department, and almost everyone agreed that black coffee and black tea are examples of clear liquid.
Reviewing the published literature, we find that several authors have studied the implications of ingestion of black coffee before elective surgery. Hutchinson et al. (2) and Maltby et al. (3) found that neither the residual gastric volume nor the gastric acidity is increased after ingestion of black coffee (150 mL) or pulp-free orange juice (150 mL) 2–3 h before surgery, with or without ranitidine. Both concluded black coffee and pulp-free orange juice may be safely allowed 2–3 h before the induction of general anesthesia. Shevde and Trivedi (4) gave 240 mL of water, pulp-free orange juice, or black coffee to volunteers and found all volunteers had a gastric volume less than 25 mL with a slight decrease in pH within 2 h of orally taking one of the three 240-mL liquids. They concluded that ingestion of (any of the three) clear liquids (water, pulp-free orange juice, or black coffee) 2 h before general anesthesia is safe.
In summary, it is clear to us, as it is to a majority of practicing anesthesiologists in North America, that black coffee, black tea, apple juice, pulp-free orange juice, cola drinks, and of course, water are examples of clear liquid that could be allowed 2–3 h before elective surgery.
Finally, we would strongly suggest that the title of this correspondence that Dr. Sosis has supplied, "Coffee is Not a Clear Liquid," is inappropriate, because it sounds like a conclusion. It is not; at best, it is controversial. By looking at the title, a casual reader will get a wrong impression about the controversy. So, we would suggest a title: "Is Coffee a Clear Liquid?"
References
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
