Intra-individual Variation of the Cuff-Leak Test as a Predictor of Post-Extubation Stridor

BACKGROUND: This was an evaluation of intra-individual variation of the cuff-leak test (ΔCLT) immediately post-intubation and pre-extubation, as a predictor of post-extubation stridor. METHODS: Prospective, clinical investigation in the ICU of a non-university hospital. CLTs were performed immediately after intubation (T0) and before extubation (T1) to evaluate the differences in cuff leak (ΔCLT = CL(T1) - CL(T0)). RESULTS: We included 104 mechanically ventilated subjects in the study over a 12-month period. The incidence of post-extubation stridor was 6.7%. Stridor was more common in females of short stature. ΔCLT was considered as significant when CL(T1) - CL(T0) was negative. The sensitivity and the specificity of the test were 86% and 48%, respectively. When we tested the pre-extubation CLT alone with a threshold of 130 mL as a predictor of post-extubation stridor, the sensitivity and the specificity of the test were 86% and 76%, respectively. CONCLUSIONS: The intra-individual variation of CLT immediately post-intubation and pre-extubation does not improve the accuracy of a standard pre-extubation CLT to predict post-extubation stridor. Moreover, the standard pre-extubation CLT did not appear in our study to be an ideal test to detect post-extubation stridor. Larger studies should be performed before generalizing these preliminary results.