Anesthesia & Analgesia: November 2016 – Volume 123 – Issue 5 – p 1158–1162
AUTHORS: Dayan, Amir C. MD et al
BACKGROUND: An intact pilot balloon assembly is crucial to the proper function of a cuffed tracheal tube. Disruption of the pilot balloon, transection of the inflation line, or valve incompetence results in cuff deflation, which may lead to inadequate ventilation and aspiration of secretions. Such failures typically result in tracheal tube replacement, but this may be a safety risk if a difficult reintubation is anticipated. We recently encountered such a patient who remained intubated postoperatively and in whom the inflation line was transected, causing a large leak. We describe a method to reconstitute the inflation line and report on the structural integrity of the repair. We hypothesized that the repaired assembly would maintain cuff pressure not statistically different from an intact device, but that the inflation line would be weaker.
METHODS: The distal (tapered) portion of a 22-gauge intravenous (IV) catheter was partially inserted into the severed end of the inflation line. A new pilot balloon was cut from an intact tracheal tube with the tubing attached, the end of which had been dilated using a 22-gauge IV catheter. The new tubing was then guided over the protruding portion of the catheter, creating an internal stent. We measured the drop in cuff pressure after 8 hours in an artificial trachea for repaired and intact tracheal tubes. We tested the integrity of the repaired segments, underwater, to high-pressure inflation. We measured the static tensile strength of the inflation line from intact and repaired tracheal tubes. Data are presented as the mean ± standard error. Differences were assessed using the unpaired, 2-sided Student t test, with P < .05 required to claim statistical significance.
RESULTS: Eight-hour interval measurements in 10 intact versus 10 repaired tracheal tubes demonstrated no significant difference in pressure drop (mean difference = 0.5 cm H2O; 95% confidence interval, −2.2 to 1.2 cm H2O; P = .54). There was no visible air leak from 10 repaired inflation line segments when the cuff was inflated to 120 mm Hg. The force needed to break the repaired inflation line was lower than for the intact tubing (n = 7 of each; mean difference = −21.9 N; 95% confidence interval, −25.7 to −18.1 N; P < 10–6). Repairs to tracheal tubes from various manufacturers with inner diameters ranging from 3.0 to 8.0 mm were successful.
CONCLUSIONS: Repairing a disrupted pilot balloon assembly using an IV catheter as a stent inside the inflation line is an effective temporizing measure in situations where ventilation is impaired and where tracheal tube replacement may present an excessive patient risk.