SHOCK OR SEPSIS EARLY DETECTION METHOD AND SYSTEM
According to various embodiments, a medical system and method for early detection of shock and/or sepsis may include devices configured to provide information about carbon dioxide and/or pH levels in a patient's tracheal tissue and in a respiratory path. Specifically, a relationship between carbon dioxide and/or pH in the tracheal tissue vs. respiratory gases (e.g., lung gases) may be used to determine if a patient is at risk of developing shock or sepsis. In certain embodiments, if carbon dioxide in the tracheal tissue deviates from end-tidal carbon dioxide, a patient may be experiencing early stages of hypoperfusion associated with shock and/or sepsis.
1 . A method, comprising:
using processing circuitry:
receiving a first signal from a first sensor in contact with a tracheal tissue of a patient, wherein the first signal is representative of a level of carbon dioxide or a pH of the tracheal tissue;
receiving a second signal from a second sensor, wherein the second signal is representative of an end-tidal level of carbon dioxide during respiration of the patient or an arterial level of carbon dioxide or an arterial pH; and
determining whether the patient is at risk for developing shock or sepsis based at least in part on a relationship between the level of carbon dioxide or pH of the tracheal tissue and the end-tidal level of carbon dioxide or the arterial level of carbon dioxide or the arterial pH.
2 . The method of claim 1 , comprising providing a user-perceptible indication related to a risk of developing shock or sepsis.
3 . The method of claim 1 , comprising displaying a comparison of the level of carbon dioxide in the tracheal tissue and the end-tidal level of carbon dioxide over time.
4 . The method of claim 1 , wherein the relationship comprises a difference between the level of carbon dioxide in the tracheal tissue and the end-tidal level of carbon dioxide.
5 . The method of claim 4 , comprising triggering an alarm when the difference between the level of carbon dioxide in the tracheal tissue and the end-tidal level of carbon dioxide is greater than a threshold.
6 . The method of claim 1 , wherein the relationship comprises a rate of change in a difference between the level of carbon dioxide in the tracheal tissue and the end-tidal level of carbon dioxide.
7 . The method of claim 1 , comprising providing a user perceptible indication that shock or sepsis therapy should be started if the patient is at risk for developing shock or sepsis.
8 . A monitor, comprising:
processing circuitry configured to execute instructions for:
receiving a first signal from a first carbon dioxide sensor in contact with a tracheal tissue of an intubated patient;
determining a level of carbon dioxide in the tracheal tissue based on the first signal;
receiving a second signal from a second carbon dioxide sensor in fluid communication with a respiratory circuit of the intubated patient;
determining an end-tidal level of carbon dioxide during respiration based on the second signal; and
determining a clinical condition of the patient based at least in part on a relationship between the level of carbon dioxide in the tracheal tissue and the end-tidal level of carbon dioxide.
9 . The monitor of claim 8 , wherein the processor comprises instructions to trigger an alarm when a difference between the level of carbon dioxide in the tracheal tissue and the end-tidal level of carbon dioxide is greater than a predetermined level.
10 . The monitor of claim 8 , comprising a display for displaying a user perceptible indication related to the clinical condition of the patient.
11 . The monitor of claim 10 , wherein the clinical condition of the patient comprises shock or sepsis.
12 . The monitor of claim 8 , wherein the relationship comprises a difference between the level of carbon dioxide in the tracheal tissue and the end-tidal level of carbon dioxide.
13 . The monitor of claim 8 , wherein the relationship comprises a rate of change of a difference between the level of carbon dioxide in the tracheal tissue and the end-tidal level of carbon dioxide.
14 . The monitor of claim 8 , wherein the processor comprises instructions for correcting for a higher baseline level of carbon dioxide in the tracheal tissue relative to the end-tidal level of carbon dioxide.
15 . The monitor of claim 8 , wherein determining the end-tidal level of carbon dioxide during respiration comprises determining an average end-tidal carbon dioxide level over a predetermined number of breaths.
16 . The monitor of claim 8 , wherein processor comprises instructions for receiving a third signal related to a pH of the tracheal tissue, and wherein between the level of carbon dioxide in the tracheal tissue and the end-tidal level of carbon dioxide is based at least in part on the pH of the tracheal tissue.
17 . A respiratory system, comprising:
a tracheal tube comprising a passageway for conveying gases to a patient;
a first sensor associated with an exterior of the tracheal tube and configured to contact a tracheal tissue when the tracheal tube is inserted in the patient;
a second sensor in fluid communication with the passageway; and
a monitor operatively coupled to the first sensor and the second sensor, the monitor comprising:
processing circuitry configured to execute instructions for:
receiving a first signal from the first sensor, wherein the first signal is representative of a level of carbon dioxide or a pH of the tracheal tissue;
receiving a second signal from the second sensor, wherein the second signal is representative of an end-tidal level of carbon dioxide during respiration of the patient; and
determining whether the patient is at risk for developing shock or sepsis based at least in part on a relationship between the level of carbon dioxide or pH of the tracheal tissue and the end-tidal level of carbon dioxide.
18 . The respiratory system of claim 17 , wherein the first sensor is disposed on a non-sealing portion of an inflatable balloon cuff associated with the tracheal tube.
19 . The respiratory system of claim 17 , wherein the first sensor is disposed on a deployable member associated with the exterior of the tracheal tube.
20 . The respiratory system of claim 17 , wherein the exterior of the tracheal tube comprises a recess adapted to accommodate the deployable member in an undeployed state.