Prevention of Perioperative Hypothermia in Transurethral Resection Under Spinal Anaesthesia

Study Overview
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Brief Summary
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Perioperative hypothermia is one of the most common anaesthetic complications, increasing the morbidity/mortality of our patients. Active prewarming with hot forced-air devices has demonstrated to be the most effective tool to prevent hypothermia, but its use is only recommended in long-term surgeries and the optimal prewarming duration has not been elucidated. Both spinal anaesthesia associated to the irrigation with liquids at low temperature instilled during transurethral resection (TUR) cause a decrease in the core temperature of the patient. This is a clinical trial comparing different time periods of prewarming in patients submitted to undergo elective transurethral resection. Our aim is to assess the effect of different time-periods of prewarming on preventing perioperative hypothermia during TUR with spinal anaesthesia. Investigators will compare different time periods: 0 minutes (control group), 15 minutes, 30 minutes and 45 minutes. 200 patients are going to be included in this study (50 patients in each group). Measurement of temperature will be performed using a tympanic thermometer and zero-heat-flux temperature sensor. Patients will be followed throughout their hospital admission. Data will be recorded using a validated instrument and will be analysed using the statistics program R Core Team.

Detailed Description
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Inadvertent perioperative hypothermia is probably the most common anaesthetic complication. Its appearance increases the morbidity of the surgical patient, increasing the incidence of cardiac events or perioperative blood loss and causes a greater time of recovery from anaesthesia. Prewarming is the most effective measure to prevent hypothermia and maintain intraoperative normothermia. However, prewarming in patients submitted to spinal anesthesia is still a weak recommendation and the optimal prewarming time has not been elucidated. Due to the searching of optimal prewarming time and the lack of evidence about the efficiency of prewarming in patients submitted to transurethral resection under spinal anaesthesia, the conductance of this clinical trial is justified.

Official Title
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Prevention of Perioperative Hypothermia in Transurethral Resection Under Spinal Anaesthesia

Conditions
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Hypothermia; Anesthesia, Perioperative Complication, Regional Anesthesia Morbidity, Temperature Change, Body, Transurethral Resection Syndrome

Intervention / Treatment
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* Device: WarmTouch total body blanket, Covidien Ltd, Mansfield, USA


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients undergoing elective Transurethral resection under spinal anesthesia. Patients older tan 18 years old. American Society of Anesthesiologists physical status classification I - III. Absence of cognitive impairment. Written informed consent before enrollment. Exclusion Criteria: Pregnancy. American Society of Anesthesiologists physical status classification IV. Active infection. Intake of antipyretics within 24 hours before surgery. Thyroid disorders. Skin lesions or History of hypersensitivity to skin contact devices.

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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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: Different time periods of prewarming will be compared: 0 minutes (control group), 15 minutes, 30 minutes and 45 minutes
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Control<br>No prewarming. Patients will be actively warmed during the intraoperative period. Tympanic thermometer and zero-heat-flux temperature sensor will be used to measure the temperature throughout the perioperative period. | |
| Experimental: Prewarming during 15 minutes<br>Active Prewarming will be performed during 15 minutes, using a forced-air blanket over the whole body and connected to a forced-air warmer set up at 43 degrees centigrade. Patients will be actively warmed during the intraoperative period. | Device: WarmTouch total body blanket, Covidien Ltd, Mansfield, USA<br>* Forced-air warming will be applied in the preanesthetic room<br>|
| Experimental: Prewarming during 30 minutes<br>Active Prewarming will be performed during 30 minutes, using a forced-air blanket over the whole body and connected to a forced-air warmer set up at 43 degrees centigrade. Patients will be actively warmed during the intraoperative period. | Device: WarmTouch total body blanket, Covidien Ltd, Mansfield, USA<br>* Forced-air warming will be applied in the preanesthetic room<br>|
| Experimental: Prewarming during 45 minutes<br>Active Prewarming will be performed during 45 minutes, using a forced-air blanket over the whole body and connected to a forced-air warmer set up at 43 degrees centigrade. Patients will be actively warmed during the intraoperative period. | Device: WarmTouch total body blanket, Covidien Ltd, Mansfield, USA<br>* Forced-air warming will be applied in the preanesthetic room<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Differences in Body Temperature among different treatment groups using tympanic thermometer and zero-heat-flux temperature sensor | To assess the effects of prewarming in preventing drop of body temperature of patients undergoing elective transurethral resection under spinal anesthesia | Throughout surgery, an average of 60 minutes. | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Length of stay in postanesthetic care unit (in minutes) | To assess the effect of prewarming in the length of stay in the Post-Anesthetic Care Unit of patients undergoing elective transurethral resection under spinal anesthesia. | Stay in Post-Anesthetic Care Unit, an average of 6 hours. | 
| Postoperative pain, using visual analogue scale (from 0 to 10) | To assess the effect of prewarming in reducing the postoperative pain at the arrival to the postanesthetic care unit of patients undergoing elective transurethral resection under spinal anesthesia | Immediate postoperative period, an average of 1 hour. | 
| Postoperative shivering (using a dichotomous scale: yes or no) | To assess the effect of prewarming in the prevalence of postoperative shivering of patients undergoing elective transurethral resection under spinal anesthesia | Immediate postoperative period, an average of 1 hour | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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body temperature, hypothermia, prewarming, regional anesthesia