Increased cuff-leak pressure after abdominal and spine surgeries: a simple and novel cuff-leak test for tracheal extubation.

PURPOSE

Cuff-leak volume (CLV) tests are recommended to avoid extubation failure. We developed a novel cuff-leak pressure (CLP) test that quantitatively assesses upper airway resistance outside the tracheal tube. We hypothesized that CLP (airway pressure during apnea with the cuff deflated under a 6 l/minute oxygen flow) would increase after surgery (primary outcome) and evaluated the accuracy and reproducibility of CLP measurements by measuring the CLV (difference in expiratory tidal volume before and after deflation of a tracheal tube cuff).

METHODS

CLV and CLP were measured before and after abdominal surgery (n = 25; abdominal group) and cervical spine surgery (n = 25; spine group) under general anesthesia and complete neuromuscular blockade.

RESULTS

In both groups, the CLP was significantly higher after surgery (median [25%, 75% interquartile ranges]) (abdominal group: 4.0 [1.0, 8.4] cmHO to 9.0 [3.4, 13.7] cmHO, P = 0.007; spine group: 8.0 [3.0, 10.9] cmHO to 11.0 [7.5, 13.5] cmHO, P = 0.038). The cutoff values for 100% negative and positive predictive values for a positive CLV test (CLV < 110 ml or 25% of the tidal volume with the cuff inflated) were 12.0 and 17.3 cmHO, respectively, with an AUC of 0.957 (95%CI 0.27-1.20). The CLP and CLV measurements were highly reproducible, as the Kendall's coefficients of concordance were 0.898 (1st and 3rd) and 0.971 (6 consecutive breaths), respectively, although the CLV progressively increased by 29.0 [1.8, 58.8] ml for the 6 consecutive breaths (P < 0.001).

CONCLUSION

Both the CLP and CLV measurements were accurate and highly reproducible to assess postoperative increase of the upper airway resistance before extubation.