Monitoring Tracheal Tube Cuff Pressures in the ICU Can Prevent Injury

“Despite increasing awareness among intensivists and respiratory therapists and more widespread use of low-pressure, high-volume cuffs, the incidence of tracheal tube cuff overinflation remains high in the contemporary American intensive care unit [ICU],” said Luc Morris, MD, from the Head and Neck Service in the Department of Otolaryngology at New York University School of Medicine during his scientific session presentation at the April 2007 meeting of the American Broncho-Esophagological Association at the Combined Otolaryngology Spring Meeting.

“This is a public health issue that otolaryngologists need to take the lead in,” continued Dr. Morris, whose paper was published in the August Annals of Otology, Rhinology, and Laryngology. “We are the airway doctors who take care of these patients when they come to us short of breath with tracheal stenosis, long after they have left the ICU. Every day, a large percentage of intubated and tracheotomized patients in our hospitals are experiencing tracheal injury. We have put the responsibility of preventing this problem on the shoulders of practitioners who are busy with other issues, and who have a hard time prioritizing this issue, because they do not see the sequelae of high cuff pressures.”

Prolonged intubation with cuffed tracheal tubes is common in ICU patients requiring mechanical ventilation. Although perioral endotracheal tubes are routinely converted to tracheotomy tubes, both types of cuffed tubes exert pressure against tracheal mucosa. Cuff pressure is a recognized risk factor for tracheal injury and subsequent tracheal stenosis.1–4 Although international studies report a 55% to 62% incidence of cuff overinflation among ICU patients,5,6 there are no data on tracheotomy tubes and no recent data from ICUs in the United States.

Auditing Cuff Pressure

To track the incidence of tracheal tube cuff overinflation and determine whether routine cuff pressure measurement is beneficial, Dr. Morris and his colleagues performed a three-month, prospective, observational study of 115 patients who had endotracheal or tracheotomy tubes. The study was conducted at two US tertiary-care academic hospitals, which monitor cuff pressure differently.

At Hospital A, respiratory therapists routinely assessed cuff pressures by palpation, but not by direct measurement, once during every 12-hour shift. At Hospital B, cuff pressures were measured with a manometer every one to two days and were informally palpated on every shift. At both hospitals, inappropriately inflated cuffs were adjusted promptly.

“We audited cuff pressures in an unannounced fashion at these hospitals at various times across daytime hours, without regard to the timing of the respiratory therapists’ rounds,” said Dr. Morris. A handheld aneroid manometer was used to measure cuff pressures via the pilot balloon, taking care not to create an air leak during measurement. If cuff pressure varied from inspiration to expiration, the mean value was recorded.