Endotracheal tube extubation detection

Abstract

Systems and methods for detecting extubation of an endotracheal tube (ETT) are described. Extubation of the ETT can be identified by comparing to a threshold, a difference between a determined first volume of breathing gas during a first inspiratory period to a determined second volume of breathing gas during a second inspiratory period. If the difference exceeds the threshold, an alarm can be activated indicating extubation. Extubation detection may also be based on a difference between inspiratory pressures during separate inspiratory periods. Partial extubation and full extubation may also be discerned. Further, extubation of an ETT may be detected without the use of an exhalation flow sensor.

What is claimed is: 
     
         1 . A ventilator-implemented method for detecting extubation of an endotracheal tube during ventilation, the method comprising:
 measuring, by a pressure sensor, inspiratory pressure during a first inspiratory period having a first time duration;   measuring, by the pressure sensor, inspiratory pressure during a second inspiratory period having a second time duration;   calculating, by the ventilator, a first integral over the first time duration of the inspiratory pressure measured during the first inspiratory period;   calculating, by the ventilator, a second integral over the second time duration of the inspiratory pressure measured during the second inspiratory period;   comparing, by the ventilator, the first integral to the second integral to determine a difference between the first integral and the second integral; and   if the difference between the first integral and the second integral is greater than a threshold, activating an alarm indicating extubation of the endotracheal tube.   
     
     
         2 . The ventilator-implemented method of  claim 1 , wherein the method is performed during volume-controlled ventilation. 
     
     
         3 . The ventilator-implemented method of  claim 1 , wherein the endotracheal tube is a neo-natal endotracheal tube. 
     
     
         4 . The ventilator-implemented method of  claim 1 , wherein the endotracheal tube has a resistance of about 13.8 H 2 O/L/sec at a flow of 0.167 L/sec. 
     
     
         5 . The ventilator-implemented method of  claim 1 , wherein the threshold is within the range of about 0.3 to 0.8. 
     
     
         6 . The ventilator-implemented method of  claim 1 , wherein the ventilator does not include an exhalation flow sensor. 
     
     
         7 . The ventilator-implemented method of  claim 1 , wherein the alarm indicates partial extubation of the endotracheal tube. 
     
     
         8 . A ventilator system comprising:
 a pressure generating system adapted to generate a flow of breathing gas;   a ventilation tubing system including a patient interface for connecting the pressure generating system to a patient, wherein the ventilation tubing system further includes an inspiratory limb, an expiratory limb, an endotracheal tube, and a wye connecting the inspiratory limb, the expiratory limb, and the endotracheal tube;   an inspiratory flow sensor coupled to at least one of the pressure generating system and the ventilation tubing system;   an inspiratory pressure sensor coupled to the inspiratory limb;   an expiratory pressure sensor coupled to the expiratory limb;   one or more processors operatively coupled to at least the inspiratory pressure sensor; and   a memory operatively coupled to the one or more processors, wherein the memory includes instructions configured cause the ventilator system to perform a set of operations upon execution by the one or more processors, the set of operations comprising:
 receive, from the inspiratory pressure sensor, inspiratory pressure during a first inspiratory period having a first time duration; 
 receive, from the inspiratory pressure sensor, inspiratory pressure during a second inspiratory period having a second time duration; 
 calculate a first integral over the first time duration of the inspiratory pressure measured during the first inspiratory period; 
 calculate a second integral over the second time duration of the inspiratory pressure measured during the second inspiratory period; 
 compare the first integral to the second integral to determine a difference between the first integral and the second integral; and 
 based on the difference between the first integral and the second integral is greater than a threshold, activate an alarm indicating extubation of the endotracheal tube. 
   
     
     
         9 . The ventilator system of  claim 8 , wherein the operations are performed during volume-controlled ventilation. 
     
     
         10 . The ventilator system of  claim 8 , wherein the endotracheal tube is a neo-natal endotracheal tube. 
     
     
         11 . The ventilator system of  claim 8 , wherein the endotracheal tube has a resistance of about 13.8 H 2 O/L/sec at a flow of 0.167 L/sec. 
     
     
         12 . The ventilator system of  claim 8 , wherein the ventilator system does not include an exhalation flow sensor. 
     
     
         13 . The ventilator system of  claim 8 , wherein the ventilator system further comprises an interface for displaying operational data for the ventilator system, and the alarm is displayed on the interface. 
     
     
         14 . A ventilator-implemented method for detecting extubation of an endotracheal tube during ventilation, the method comprising:
 measuring, by a pressure sensor, inspiratory pressure during a first inspiratory period having a first time duration;   measuring, by the pressure sensor, inspiratory pressure during a second inspiratory period having a second time duration;   calculating, by the ventilator, a first integral over the first time duration of the inspiratory pressure measured during the first inspiratory period;   calculating, by the ventilator, a second integral over the second time duration of the inspiratory pressure measured during the second inspiratory period;   determining a difference between the first integral and the second integral;   comparing the difference to a first threshold and a second threshold, wherein the second threshold is greater than the first threshold; and   based on the comparison of the difference to the first threshold and the second threshold, activating an alarm indicating extubation of the endotracheal tube.   
     
     
         15 . The ventilator-implemented method of  claim 14 , wherein the difference is in between the first threshold and the second threshold, and the alarm indicates partial extubation of the endotracheal tube. 
     
     
         16 . The ventilator-implemented method of  claim 14 , wherein the difference is greater than the second threshold, and the alarm indicates full extubation of the endotracheal tube. 
     
     
         17 . The ventilator-implemented method of  claim 14 , wherein the first threshold is within the range of about 0.3 to 0.8. 
     
     
         18 . The ventilator-implemented method of  claim 14 , wherein the endotracheal tube is a neo-natal endotracheal tube. 
     
     
         19 . The ventilator-implemented method of  claim 14 , wherein the endotracheal tube has a resistance of about 13.8 H 2 O/L/sec at a flow of 0.167 L/sec. 
     
     
         20 . The ventilator-implemented method of  claim 14 , wherein the method is performed during volume-controlled ventilation.