Sleeve-based body temperature regulation
A heating system comprises a wearable sleeve, a first heating pad associated with a first portion of the wearable sleeve, a second heating pad associated with a second portion of the wearable sleeve, one or more temperature sensors associated with the wearable sleeve, and control circuitry communicatively coupled to the first heating pad, the second heating pad, and the one or more temperature sensors. The control circuitry is configured to receive one or more temperature signals from the one or more temperature sensors, determine a temperature associated with a patient based on the one or more temperature signals, determine that the temperature is less than a target temperature value, and at least partly in response to said determining that the temperature is less than the target temperature value, activate at least one of the first heating pad or the second heating pad.
1. A wearable heating sleeve comprising:
a first sleeve portion configured to be secured to a popliteal fossa of a patient's leg;
a first heating pad coupled to the first sleeve portion;
a second sleeve portion configured to be secured to a foot of the patient's leg;
a second heating pad coupled to the second sleeve portion;
one or more temperature sensors associated with at least one of the first sleeve portion or the second sleeve portion;
a third sleeve portion configured to be secured to a calf of the patient's leg;
one or more compression bladders associated with the third sleeve portion; and
control circuitry electrically coupled to the first heating pad, the second heating pad, and the one or more temperature sensors, the control circuitry configured to:
determine a first risk weight based on a surgery classification of a surgical operation associated with the patient;
determine a second risk weight based on an anesthesia condition of the patient;
receive one or more temperature signals from the one or more temperature sensors;
determine an estimated core temperature of the patient based on the one or more temperature signals;
determine a third risk weight based on the estimated core temperature;
determine a risk value associated with the patient based at least in part on a weighted, normalized summation of the first risk weight, the second risk weight, and the third risk weight; and
at least partly in response to the risk value, activate the first heating pad, the second heating pad, and the one or more compression bladders.
2. The wearable heating sleeve of claim 1 , wherein the control circuitry is electrically coupled to the first heating pad, the second heating pad, and the one or more temperature sensors at least in part by conductive wiring that extends externally of the first, second, and third sleeve portions.
3. The wearable heating sleeve of claim 1 , wherein the control circuitry is further configured to, based at least in part on the estimated core temperature, determine an amount of time until hypothermia is estimated to occur.
4. A heating system comprising:
a wearable sleeve;
a first heating pad associated with a first portion of the wearable sleeve;
a second heating pad associated with a second portion of the wearable sleeve;
one or more temperature sensors associated with the wearable sleeve; and
control circuitry communicatively coupled to the first heating pad, the second heating pad, and the one or more temperature sensors, the control circuitry configured to:
receive one or more temperature signals from the one or more temperature sensors;
estimate a core temperature associated with a patient based on the one or more temperature signals;
determine a temperature error value representing an error between the estimated core temperature and a target temperature value;
determine a proportional control component based on the temperature error value;
determine an integral control component based on an accumulated sum of past temperature error values;
determine a derivative control component based on a rate of change of the temperature error value; and
activate at least one of the first heating pad or the second heating pad based on the proportional control component, the integral control component, and the derivative control component.
5. The heating system of claim 4 , further comprising one or more compression devices associated with a third portion of the wearable sleeve.
6. The heating system of claim 5 , wherein the control circuitry is further configured to, in response to the proportional control component, the integral control component, and the derivative control component, activate the one or more compression devices.
7. The heating system of claim 4 , wherein:
the first heating pad is a popliteal fossa heating pad;
the second heating pad is a foot heating pad; and
the control circuitry is configured to perform said activating at least one of the first heating pad or the second heating pad by activating the popliteal fossa heating pad and the foot heating pad between a maximum temperature and a minimum temperature such that the popliteal fossa heating pad reaches the minimum temperature when the foot heating pad is at the maximum temperature and the foot heating pad reaches the minimum temperature when the popliteal fossa heating pad is at the maximum temperature.
8. The heating system of claim 4 , wherein the control circuitry is further configured to generate a time value parameter indicating a period of time expected until the patient is in range of hypothermia based at least in part the one or more temperature signals.
9. The heating system of claim 4 , wherein:
the control circuitry is further configured to determine an anesthesia state of the patient; and
said activating the at least one of the first heating pad or the second heating pad is based at least in part on the anesthesia state of the patient.
10. The heating system of claim 9 , wherein said determining the anesthesia state of the patient is based at least in part on a detection that a heart rate of the patient has dropped a threshold amount.
11. The heating system of claim 9 , wherein a weight assigned to the anesthesia state of the patient decreases over time.
12. The heating system of claim 4 , wherein the control circuitry is further configured to determine a hypothermia risk value based at least in part on the estimated core temperature.
13. The heating system of claim 12 , wherein said hypothermia risk value is based at least in part on a weighted combination of at least one dynamic parameter and at least one static parameter, each of the at least one dynamic parameter and the at least one static parameter having associated therewith a risk weight.
14. The heating system of claim 13 , wherein:
the at least one dynamic parameter comprises at least one of the estimated core temperature, patient skin temperature, environmental temperature, or a patient vital signal level; and
the at least one static parameter comprises at least one of patient demographic group, patient comorbidity status, or procedure type.
15. The heating system of claim 4 , wherein the estimated core temperature is a predicted future body temperature of the patient that is based at least in part on the one or more temperature signals and a rate of change of the one or more temperature signals.
16. The heating system of claim 15 , wherein the predicted future body temperature is further based at least in part on anesthesia depth.
17. The heating system of claim 4 , wherein said activating at least one of the first heating pad or the second heating pad involves alternating activation of the first heating pad and the second heating pad.
18. The heating system of claim 4 , wherein:
the control circuitry is further configured to:
determine a skin temperature of the patient based on the one or more temperature signals;
determine that the skin temperature is greater than a safety threshold; and
at least partly in response to said determining that the skin temperature is greater than the safety threshold, deactivate at least one of the first heating pad or the second heating pad.
19. The heating system of claim 4 , wherein the control circuitry is embodied, at least in part, in a controller electrically and physically couplable to the wearable sleeve via one or more cables.
20. The heating system of claim 4 , wherein the control circuitry is embodied, at least in part, in a controller communicatively couplable to at least one of the first heating pad, the second heating pad, or the one or more temperature sensors via a wireless connection.