This increased risk was noted in patients who had uvulopalatopharyngoplasty (UPPP) -- a procedure in which excess tissue is removed from the throat -- with tonsillectomy, but not in patients who had tonsillectomy alone.

The study authors analyzed post-operative bleeding rates among more than 1,000 tonsillectomy patients between 2000 and 2005. The overall rate of bleeding was 6.7 percent, but that number was 10.2 percent for smokers and 5.4 percent for nonsmokers.

The large difference between the two groups was due to the high rate of post-operative bleeding among smokers who underwent UPPP -- 10.9 percent vs. 3.3 percent in nonsmokers.

"Futher investigation of this relationship is needed, with stratification of patients by the number of cigarettes smoked and attention to the length of time before and/or after surgery that patients refrain from smoking," the study authors wrote.

Understanding the link between smoking and post-operative bleeding may help doctors better counsel patients before surgery, the researchers said.

The study also found that men who had tonsillectomy alone were much more likely than women to have post-operative bleeding -- 11.2 percent vs. 5.4 percent.

The findings were published in the August issue of the journal Archives of Otolaryngology--Head & Neck Surgery.

More information

The American Academy of Otolaryngology -- Head and Neck Surgery has more about tonsillectomy procedures.

SOURCE: JAMA/Archives journals, news release, Aug. 18, 2008

-- Robert Preidt