the influence of endotracheal tube design on fluid leakage into the lungs during surgery

Conditions: Respiratory Aspiration

Summary: surgical patients have an endotracheal tube inserted into their windpipe to help them breathe while under general anesthesia. these tubes have a "cuff" on the outside that is inflated in the trachea to help prevent fluids from leaking into the lungs. these cuffs come in different shapes and sizes. the taperguard endotracheal tube has a taper-shaped cuff that has been shown in animals to decrease the leakage of fluid past the cuff better than a traditional tube that has a barrel-shaped cuff. this study is designed to examine whether the use of the taperguard tube during surgery on humans decreases the amount of leakage past the cuff to a greater degree than the traditional barrel-shaped cuff. in addition, the study will investigate whether the use of the taperguard tube is associated with a decrease in respiratory complications often seen following surgery which may be related to fluid leaking past the cuff and into the lungs. it is thought that the use of the taperguard endotracheal tube will result in a decrease in fluid leakage past the cuff and that it will be associated with a decrease in respiratory complications during the 30 days after surgery.

this study is designed to yield data on the intraoperative use of taperguard™endotracheal tubes and its potential influence on postoperative pulmonary complications and outcomes. the taperguard basic tube has a taper-shaped cuff and has been shown, via bench and animal testing, to decrease microaspiration, which has been associated with respiratory difficulties. the intraoperative use of this tube (i.e. during short term intubation), and its impact on postoperative complications and outcomes has not been investigated. this study will determine whether the intraoperative use of the taperguard tube results in a decrease in microaspiration compared to the hi-lo endotracheal tube having a barrel-shaped cuff. moreover, the relationship between a decrease in microaspiration and subsequent decrease in postoperative respiratory complications will be explored.

Eligibility criteria:
inclusion criteria: * male or female of all races * older than 18 years old * scheduled for an elective surgical procedure under general anesthesia for no less than 2hr and no more than 12hr with planned endotracheal intubation via the oral route * willing and able to give informed consent for participation in the study * anticipated extubation at the conclusion of general anesthesia in the operating room and prior to admission to the pacu * expected hospital stay of greater than or equal to 23hrs exclusion criteria: * preexisting acute respiratory illness requiring antibiotic treatment within the two weeks prior to surgery * temperature of over 101 degrees f (38.3 c) at time of scheduled surgery * surgical requirement for naso-tracheal intubation * patients undergoing surgical procedures directly on the lungs, trachea, or airways * presence of tracheostomy * history of allergic reaction to methylene blue * methemoglobinemia, glucose-6-phosphate (g6pd) deficiency * renal insufficiency or failure * requirement for prolonged intubation and/or ventilation beyond the point of pacu admission * intraoperative use of nitrous oxide, to avoid the increase in cuff pressure due to diffusion of gas over time * psychiatric drugs of the following classifications: selective serotonin reuptake inhibitors (ssris), serotonin-norepinephrine reuptake inhibitors (snris), tricyclic antidepressants (tcas), and monoamine oxidase inhibitors (maois). * patients younger than 18 years of age * prone positioning during surgery * pregnant or lactating women based on standardized preoperative screening protocols * legally detained prisoner status * unwilling or unable to give informed consent for participation in the study

Keywords: aspiration, respiratory