Observational Examination of Thermoregulation in Total Joint Arthroplasty

Study Overview
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Brief Summary
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Total joint patients have poor outcomes with infection since they are having permanent hardware implanted. Infection prevention in this group is therefore critical and a major source of discussion in both the orthopedic and anesthesia literature. Hypothermia has been shown to increase the risk of infection and blood loss. However, studies have not examined when in the operation or how fast patients temperatures drop. This study will observe how patients' temperatures change during total joint arthroplasty. By identifying when body temperature changes occur, prevention strategies may be developed and implemented.

Detailed Description
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Peri-operative hypothermia can have deleterious effects. While there is no standard consistent definition within the literature mild hypothermia is commonly defined as a core temperature between 34 and 36 °C. Mild hypothermia has been shown to increase the occurrence of surgical site infections, cardiac morbidity, coagulopathy leading to increased blood loss and transfusion requirements, impaired drug metabolism, and prolonged emergence from anesthesia. In addition, there is evidence that maintaining intra-operative normothermia can shorten hospital length of stay. Despite the fact that intra-operative temperature monitoring and warming are considered standard of care, peri-operative hypothermia in total joint arthroplasty patients remains an issue for several reasons. A large proportion of patient undergoing joint replacement are elderly, making them susceptible to peri-operative hypothermia. In addition, regional anesthesia causes vasodilation and promotes heat flow from the core to the periphery and impairs central and autonomic thermoregulation such that patients receiving neuraxial anesthesia can be particularly susceptible to perioperative hypothermia. Finally, core temperature monitoring is typically not used during regional anesthesia and hypothermia may go undetected for long periods of time. The primary goal of this study was to examine the incidence of hypothermia during lower extremity arthroplasty. A secondary aim was to identify patient and operative factors associated with hypothermia in order to improve future preventative strategies. Our hypothesis was that peri-operative hypothermia occurs in the majority of patients undergoing lower extremity arthroplasty. In addition, we hypothesized that certain patient and anesthetic factors (such as low body mass index and receiving general anesthesia) would increase the incidence of hypothermia.

Official Title
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Observational Examination of Thermoregulation in Total Joint Arthroplasty

Conditions
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Hypothermia

Intervention / Treatment
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* Other: Observation Of Temperature


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adults 18 years of age and over that are scheduled to undergo total hip or total knee joint arthroplasty. Exclusion Criteria: Patients unable to give informed consent will be excluded.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Joint Arthroplasty<br>Participants undergoing joint replacement | Other: Observation Of Temperature<br>* Participants temperature will be recorded perioperatively.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Incidence of Hypothermia | The incidence of ever being hypothermic (temperature < 36.0 °C at one or more measurements) was the primary outcome. All temperatures were assessed with an Exergen temporal thermometer (precise to 0.1 °C). Each temporal measurement was taken and recorded three times for accuracy and the mean value utilized for data analysis at each time point. Temperatures were measured upon (1) leaving holding area; (2) operating room (OR) arrival; (3) after anesthetic induction; (4) upper body forced air warmer initiation (used for all patients); (5) incision; (6-8) every 30 minutes after incision; (9) leaving the OR; and (10) arrival to PACU. OR temperature and humidity were recorded throughout. | Starting with temperature measurement prior to leaving preoperative holding for OR and ending after temperature taken on arrival in recovery room | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Hypothermia, Total Hip Joint Prosthesis, Total Knee Joint Prosthesis