The Impact of Age and Gender on Cuff Leak Volume Tests

Abstract

Background:

Although a cuff leak volume (CLV) test has been proposed as an approach to predicting the occurrence of post-extubation stridor, the volume below 110 mL of tidal volume (a quantitative cuff leak test) is highly likely to cause laryngeal edema or upper airway obstruction and subsequently result in re-intubation. The factors that age and gender affect its severity and specificity are still unknown. Due to the fact that the aging community is a global concern, the issue of limiting CLV to no more than 110ml as a positive threshold is worthy of discussion. We hypothesized that (1) among the medical ICU population, there is a significant difference between male and female in the CLV test and (2) there is a significant relationship between the CLV and the patient's age.

Methods:

This is an exploratory study on mechanically ventilated patients after at least 48 h or more planned extubation. They passed the following weaning profiles: RSBI, PImax, PEmax, and CLV. The patients needed to meet the 3 criteria. To get its mean value, the test was measured 3 times and recorded. Patients were observed for 72 h after planned extubation. During this period of time, the ICU ventilators with NIV mode were utilized in case of respiratory failure. If re-intubated patients met at least one of the following criteria: lack of improvement in the PaCO₂, decrease in SpO₂ less than 88%, changes in mental status, sighs of respiratory muscle fatigue, they were treated with mechanical ventilation.

Results:

The patients undergoing scheduled extubation after 48 h and 119 patients from April 2015 to March 2016 received NIV mechanical ventilation. They were 68 males and 51 females, whose general clinical characteristics and physiologic parameters did not differ significantly at the beginning of the study and the data served as the baseline. Their mean age of male and female patients was 69.5 ± 6.1 y and 75.7 ± 6.5 y, respectively. The CLV below 110 mL for male and female was in turn 102 mL ± 5.8 mL and 94 mL ± 4.6 mL. There was no significant difference in gender and age brackets except the CLV below the reference value. Moreover, the overall re-intubation rate was 13%.

Conclusions:

Results show that the success rate is high when the CLV is lower than 110 mL prior to extubation owing to re-intubation rate 13%. The data also suggests that age and gender may affect the CLV. A low value is a good predictor of successful extubation. However, it should be used with caution when delaying extubation in this regard.