STUDY ON UTILITY OF INFRARED THERMOGRAPHY IN CONJUNCTION WITH POINT OF CARE ULTRASOUND IN PROFILING SHOCK IN PATIENTS PRESENTING TO EMERGENCY MEDICINE DEPARTMENT

1. Title of the project: Study on Utility of Infrared Thermography in Conjunction with Point of Care Ultrasound in Profiling Shock in Patients Presenting to Emergency Medicine Department

2. Type of Study: Prospective observational study.

3. Aims & objectives

Primary Objective: To assess severity of shock based on Infrared Thermography (IR) imaging (mottling score) in comparison with laboratory assessment

Secondary objective: To compare the accuracy of shock category prediction based on Infrared Thermography imaging in comparison with Point of Care Ultrasound (POCUS) assessment.  To assess feasibility of profiling and categorizing shock into warm shock and cold shock based on IR Thermography imaging

4. Justification for study (whether of national significance with rationale) : IR Camera along with Rapid Ultrasound in Shock (RUSH protocol) together can be used to classify shock hence giving a better overall picture of the type of shock .The time and expertise required to undertake Point of Care Ultrasound scans mitigates a potential shortcoming of this technology .Peripheral temperature varies in sepsis, with patients first undergoing a peripheral warm phase (due to vasodilatation–‘warm shock’) followed by increasingly cold peripheries as increasing systematic vascular resistance . These changes can be picked up using IR camera in a lesser time compared to Point of Care Ultrasound. Hence IR has a potential use in quick profiling of patients coming with shock. We also hypothesize that IR along with Artificial intelligence pattern recognition may be applicable in profiling shock in high volume Emergency Department settings .

5. Departments involved: Department of Emergency medicine

6. Study period: 18 months after IEC and CTRI

7. Sample size : 132. SAMPLE SIZE CALCULATION  132

8. Materials and methods :

Inclusion criteria : All patients >18 years of age admitted to the ED with shock . Shock defined as: 1)Heart rate > 110 2)Systolic BP <90  3)Lactate > 2mmol/L or >16mg/dL

Any 2 out of 3 above criteria based on consensus definition

Exclusion criteria: Patients who do not consent to the study. Patients with active external hemorrhage .Patients with cellulitis/Limb injuries

Tools used: Data will be calculated and assessed on the basis of statistical analysis software and IR camera software. A portable point of care ultrasound machine  ·  A Handheld thermal camera (FLIR E8-XT) .Tympanic Thermometer for core temperature . Monitor for Assessing vitals.

9. Detailed description of procedure / processes : Patients >18 years of age presenting to the Emergency medicine department fulfilling the definition of shock will be considered for inclusion. Informed consent will be taken either from the patient or a legally accepted representative when the patient is not in a capacity to consent for the same. After Informed consent, demographic details, vital parameters, salient laboratory investigations (as mentioned in the proforma) will be noted. Point of Care Ultrasound examination will be performed as per protocol .  Core temperature measurement will be done using tympanic thermometry and peripheral temperature shall be recorded using an infrared camera(FLIR E8) with in half an hour after completing RUSH protocol .The IR camera will be auto calibrated. Other non confounders of IR thermography will be noted . All four limbs will be imaged independently (excluding the one with IV access), at the tip of the index finger, forearm, great toe, knee and the highest gradient will be considered. Infrared thermography will be performed at the bedside at approximately 1 m distance within 60 minutes of arrival in the ER to allow acclimatization and minimize errors in temperature recordings. The IR mottling score of the patient will be noted and calculated from the images .The score ranged based on the extension of the mottling area from the center of the knees to the peripheral areas .Resuscitation and ongoing management of the patient will not be interrupted for the images . Limb temperature gradient patterns will be noted and mottling score will be noted.

10. Outcome measures : Correlation of shock with core to peripheral temperature gradient and POCUS in classifying the type of shock

11. Potential risks and benefits : Benefits: Will help evaluate and classify the type of shock and its further management based on the initial assessment . Risks- Risks: Less than minimal.  IR is a noncontact technique and does not have any radiation hazard . It has sensor for Infrared rays and does not emit Infrared rays . It is a handheld device and held bedside

12. Ethical considerations and methods to address issues : The study will commence only after getting approval from IEC. Informed consent will be obtained from all the patients for inclusion into the study. Identification: No direct identifiers will be used. Thermal images will be obtained only of the limbs. Exposure: As only the limbs shall be imaged the patient does not require to be fully exposed. Delay in treatment: No delay in treatment is anticipated due to data collection. Transmission of infection: Infrared thermography is a non contact method and is not anticipated to transmit infection.

13. Budget and proposed funding source : The department has a functional IR camera at present .Rs 2000 for stationary purposes . Funding self

14. Review of literature  : Shock is defined as a mismatch in oxygen delivery and cellular uptake. Point-of-care ultrasound has been a safe, rapid, and noninvasive method used in emergency departments. Resuscitative ultrasound, as a tool for initial management of patients in a state of shock, has resulted in a rapid and accurate initial diagnosis and better management . Among resuscitative ultrasound techniques, the RUSH protocol (Rapid Ultrasound in Shock) is based on three major steps: the pump, the tank, and the pipes . CLASSIFICATIONS OF SHOCK Many authorities categorize shock into 4 classic subtypes .The first is hypovolemic shock. This condition is commonly encountered in the patient who is hemorrhaging from trauma, or from a nontraumatic source of brisk bleeding such as from the gastrointestinal (GI) tract or a rupturing aortic aneurysm. Hypovolemic shock may also result from non hemorrhagic conditions with extensive loss of body fluids, such as GI fluid loss from vomiting and diarrhea. The second subtype of shock is distributive shock. The classic example of this class of shock is sepsis, in which the vascular system is vasodilated to the point that the core vascular blood volume is insufficient to maintain end organ perfusion. Other examples of distributive shock include neurogenic shock, caused by a spinal cord injury, and anaphylactic shock, a severe form of allergic response . The third major form of shock is cardiogenic shock, resulting from pump failure and the inability of the heart to propel the needed oxygenated blood forward to vital organs. Cardiogenic shock can be seen in patients with advanced cardiomyopathy, myocardial infarction, or acute valvular failure. The last type of shock is obstructive shock. This type is most commonly caused by cardiac tamponade, tension pneumothorax, or large pulmonary embolus. Many patients with obstructive shock will need an acute intervention such as pericardiocentesis, tube thoracostomy or anticoagulation, or thrombolysis . Medical infrared imaging has potential uses in emergency care as many acute presentations change blood flow and hence also change thermal patterns . It is a common clinical observation that peripheral temperature varies in sepsis, with patients first undergoing a peripheral warm phase (due to vasodilation–‘warm shock’) followed by increasingly cold peripheries as increasing systemic vascular resistance  Infrared thermography is non-invasive technology with an infrared camera that records infrared radiations emitted by the body and deduces temperature. The infrared camera creates images based on differences in surface temperature by detecting infrared radiation that emanates from objects and translates temperatures in a color gradient in photography . Infrared thermography offers a useful and non-invasive approach to the diagnosis of many disorders such as circulatory abnormalities .Thermography can help in complex situations in suspected septic patients to admission decisions in ICU.