The following is a summary of “Utilization of a Risk Stratification Tool and Volume-Based Cuff Leak Test to Assess Postextubation Stridor,” published in the March 2023 issue of Respiratory Care by Kallet et al.
The occurrence of postextubation stridor (PES) poses an immediate threat to the patient’s life. To optimize patient safety, adopting a methodical approach to assess patients for potential PES risk factors and employing a uniform test to gauge such risk is imperative. This study retrospectively analyzed quality assurance data from adult subjects. The data included standardized surveillance screening criteria and a volume-based cuff leak test (CLT) to assess the risk of post-extubation stridor (PES) in subjects primarily undergoing surgical trauma and neurotrauma procedures. Data about the subjects with pulmonary embolism syndrome (PES) were also gathered. All intubated patients in our surgical trauma, neurotrauma, and medical ICUs were subjected to data collection from May 2010 to December 2017. Respiratory therapists have received training in conducting Pulmonary Embolism Severity (PES) risk assessment surveillance and a volume-based Chest Physiotherapy (CPT) technique.
A pre hoc cutoff leak volume of <110 milliliters has been established to define a true positive test result when accompanied by PES. Conversely, a leak volume of ≥110 milliliters indicates a negative test result without PES. The Kruskal-Wallis tests were utilized to analyze multiple comparisons, while Fisher exact tests were employed to assess dichotomous variables. The significance level, alpha, was established at 0.05. Among the 681 pre-extubation clinical laboratory tests (CLTs), ∼ 85% yielded true-negative outcomes. The remaining 15% of the tests comprised true-positive (∼ 4%), false-negative (∼ 5%), and false-positive (∼ 6%) results. The positive and negative predictive values yielded 0.42 (0.32–0.54) and 0.94 (0.92-0.96), respectively. Based on the results, the PES likelihood ratio yielded a value of 7.0, with a corresponding correct classification rate of 89%. Out of the 112 cases of PES, there 115 incidences were observed. Among these, 67% of the cases were female, and 48% had a history of acute brain injury. In subjects primarily diagnosed with surgical trauma and neurotrauma who have a cerebrospinal fluid leak, a volume of ≥ 110 mL is linked to a risk of post-traumatic hydrocephalus of ∼ 6%. On the other hand, when the leak volume is < 110 mL, the risk of post-traumatic hydrocephalus increases by a factor of 7.