Peak Flow Rate During Induced Cough: A Predictor of Successful Decannulation of a Tracheotomy Tube in Neurosurgical Patients

Abstract

Background An accurate predictor of successful decannulation in neurosurgical patients that indicates the best time for tracheotomy decannulation would minimize the risks of continued cannulation and unsuccessful decannulation. Objective To determine whether the peak flow rate during induced cough is an appropriate predictor of successful decannulation. Methods A total of 32 neurosurgical patients with a tracheotomy were enrolled. The highest peak expiratory flow rate during 3 induced coughs, the total volume of tracheal secretions collected in 6 hours, and scores on the Glasgow Coma Scale were recorded. Logistic regression analysis was applied to determine the relationship between these variables and successful decannulation (reintubation not required within 72 hours). Results Decannulation was attempted in 23 of 32 patients. The remaining 9 patients were considered clinically inappropriate for the procedure. Of the 23 patients decannulated, 2 required reinsertion of the tracheotomy tube. Analysis revealed that peak flow rate during induced cough (odds ratio, 1.12; 95% confidence interval, 1.02-1.23) was independently associated with successful decannulation (accuracy, 75%; sensitivity, 85.7%; specificity, 54.5%). The receiver operating characteristic curve indicated an optimal cutoff point of 29 L/min. Conclusion Measurement of peak flow rate during induced cough is a simple and reproducible intervention that improves predictability of successful decannulation in patients with tracheotomy.

The Ventilator Discontinuation Process: An Expanding Evidence BaseDiscussion

“…4 Peak cough flows of Ͼ 160 L/min predict successful translaryngeal extubation or tracheostomy tube decannulation in neuromuscular or spinal cordinjured patients. 62 Cough velocities of 0.5-1.0 L/s have also been shown in other studies to be compatible with successful extubation. 63 The importance of intact cognitive function on extubation success is controversial.…”

Predicting Extubation Outcome by Cough Peak Flow Measured Using a Built-in Ventilator Flow Meter

“…21 However, objective assessment has been called for 13,22 because some publications assessing the clinical consequences of extubation failure were usually limited by the absence of objective assessment of cough strength. 4 Furthermore, when objective assessments were employed, a variety of measurement conditions were used (spontaneous and voluntary cough 15 ; spontaneous but involuntary cough 10 ; manually assisted cough 12 ; and inclusion or not of neurosurgical subjects with oral endotracheal tubes or tracheostomy 23,24 with possible severe cognitive impairments preventing an adequate response to cough instruction). This has also led to a wide range of cut-off values (Ϫ80 L/min was most adapted for reflex cough in the specific context of neuro-ICU 24 ; Ϫ35 L/min was proposed in a medical ICU 15 ;Ϫ29 L/min was proposed for decannulation 23 ).…”

“…4 Furthermore, when objective assessments were employed, a variety of measurement conditions were used (spontaneous and voluntary cough 15 ; spontaneous but involuntary cough 10 ; manually assisted cough 12 ; and inclusion or not of neurosurgical subjects with oral endotracheal tubes or tracheostomy 23,24 with possible severe cognitive impairments preventing an adequate response to cough instruction). This has also led to a wide range of cut-off values (Ϫ80 L/min was most adapted for reflex cough in the specific context of neuro-ICU 24 ; Ϫ35 L/min was proposed in a medical ICU 15 ;Ϫ29 L/min was proposed for decannulation 23 ). However, in the medical ICU context, a CPF threshold of around Ϫ60 L/min was the most consensual; the intrinsic performance initially observed for a threshold of Ͻ Ϫ60 L/min (sensitivity Fig.…”

“…It is also worth noting that this information has rarely been reported in previous studies [8][9][10][11]24 ; the only study that seems to have provided these data was an investigation of a non-ICU decannulation protocol for which 38.5% of subjects were not included. 23 This study was not restricted to a particular group of subjects according to the complexity of their weaning process. However, although the population was not formally described according to the more recently published "separation attempt," 27 an indirect comparison can be made.…”

Comparative Analysis Between Cough Peak Flow And Cough Strength Score in Evaluating Patients for Scheduled Extubation

“…The strength of a cough in addition to the presence of secretions are the two major predictors of successful extubation during weaning off the mechanical ventilation (10,11) . On the other hand, the recognition of the exact predictors of decannulation outcome may help in decreasing the intubation time and enhance the clinical decision to decannulate patients which reduces the risk of infection associated with the prolonged incubation (12) . Reintubation could be anticipated by evaluating the CPF before extubation (13) .…”