Thoracic Aortic Disease
Conditions
Brief summary
Hypothermic circulatory arrest is an important surgical technique, allowing complex aortic surgeries to be performed safely. Hypothermic circulatory arrest provides protection to cerebral and visceral organs, but may result in longer cardiopulmonary bypass times during surgery, increased risks of bleeding, inflammation, and neuronal injury. To manage these consequences, a trend towards warmer core body temperatures during circulatory arrest has emerged. This trial will randomize patients to either mild (32°C) or moderate (26°C) hypothermia during aortic hemiarch surgery to determine if mild hypothermia reduces the length of cardiopulmonary bypass time and other key measures of morbidity and mortality.
Interventions
PROCEDUREHypothermic circulatory arrest
During cardiac surgery requiring circulatory arrest, the patient's body temperature is lowered significantly to reduce the cellular metabolic rate and reduce ischemic injury.
Sponsors
Ottawa Heart Institute Research Corporation
Study design
Allocation
RANDOMIZED
Intervention model
PARALLEL
Primary purpose
TREATMENT
Masking
DOUBLE (Subject, Outcomes Assessor)
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Age ≥ 18 years * Elective aortic hemiarch surgery * Planned unilateral selective anterograde cardioplegia * Anticipated lower body arrest time of \< 20 minutes * Able to provide written informed consent
Exclusion criteria
* Surgery for acute aortic dissection or emergent operations * Total arch replacement * Inability to perform unilateral selective anterograde cerebral perfusion (uSACP) * Patients with known/documented coagulopathy * Patients with cold agglutinin disease or those that test positive on routine preop screening * Pre-existing severe neurological impairment or inability to accurately assess neurocognitive function as determined by the operating surgeon * Severe carotid disease, defined as: any patient with previously documented carotid stenosis of \> 70% (via Doppler ultrasound (US), magnetic resonance angiography (MRA), or computer tomography angiography (CTA)) without neurological deficits; or carotid stenosis \> 50% with neurological deficits; or previous carotid endarterectomy or stenting * Patients in renal failure or currently being treated with renal replacement therapy (RRT) or estimated glomerular filtration rate (eGFR) \< 30 ml/min/1.73m2 * Use of an investigational drug or device at time of enrollment * Participation in another clinical trial which interferes with performance of the study procedures or assessment of the outcomes
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Composite endpoint of neurologic and acute kidney injury | Up to 90 days after surgery. | The primary objective of this study is to determine whether mild hypothermia (32°C) during aortic hemiarch surgery using unilateral selective anterograde cerebral perfusion (uSACP), is superior to moderate hypothermia (26°C) in reducing the composite endpoint of neurologic and acute kidney injury. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Incidence of Silent Strokes | Up to 90 days after surgery. | Comparison of mild (32°C) vs moderate (26°C) hypothermia in aortic hemiarch surgery with respect to the incidence of silent strokes, defined as infarctions identified during magnetic resonance imaging (MRI) in patients without neurologic symptoms. |
| Incidence of Acute Kidney Injury (AKI) | Up to 90 days after surgery. | Comparison of mild (32°C) vs moderate (26°C) hypothermia in aortic hemiarch surgery with respect to the incidence of acute kidney injury (AKI), defined as Stage 1 or greater using the KDIGO criteria. Using the KDIGO criteria, Stage 1 AKI is defined as an increase in serum creatinine of 1.5-1.9x the baseline or an increase \>= 27umol/L with urine output \<0.5mL/kg/hour for 6-12 hours. |
| Incidence of Delirium | Up to 90 days after surgery. | Comparison of mild (32°C) vs moderate (26°C) hypothermia in aortic hemiarch surgery with respect to the incidence of delirium, using the Confusion Assessment Method (CAM). The Confusion Assessment Method defines delirium as the presence of acute changes in mental status with fluctuating course, plus inattention and the presence of either disorganized thinking OR altered level of consciousness. |
| Death | Up to 90 days after surgery. | Comparison of mild (32°C) vs moderate (26°C) hypothermia in aortic hemiarch surgery with respect to the incidence of death |
| Evaluate differences in the duration of cardiopulmonary bypass used in patients who receive mild or moderate hypothermic circulatory arrest during aortic hemiarch surgery | During the index procedure | Comparison of mild (32°C) vs moderate (26°C) hypothermia in aortic hemiarch surgery with respect to the length of time that the patient remains on cardiopulmonary bypass. |
| Rates of Neurologic Injury | Up to 90 days after surgery. | Comparison of mild (32°C) vs moderate (26°C) hypothermia in aortic hemiarch surgery with respect to incidence of neurologic injury, including transient ischemic attack (TIA) and permanent neurological dysfunction (PND) or stroke. |
| Incidence and quantity of perioperative blood transfusions | Up to 90 days after surgery. | Comparison of mild (32°C) vs moderate (26°C) hypothermia in aortic hemiarch surgery with respect to the number and quantity of perioperative blood transfusions |
| Incidence of prolonged Mechanical Ventilation | Up to 90 days after surgery. | Comparison of mild (32°C) vs moderate (26°C) hypothermia in aortic hemiarch surgery with respect to the duration of mechanical ventilation. Mechanical ventilation will be defined as use of a mechanical ventilator ≥48 hours. |
| Perioperative Myocardial Infarction | Up to 48 hours after surgery. | Comparison of mild (32°C) vs moderate (26°C) hypothermia in aortic hemiarch surgery with respect to the incidence of perioperative myocardial infarction. This will be clinically diagnosed using a combination of electrocardiographic (new Q wave on 12 lead ECG) and/or biochemical (TnI \> 45 ng/L) markers. |
| Length of Stay | Up to 90 days after surgery. | Comparison of mild (32°C) vs moderate (26°C) hypothermia in aortic hemiarch surgery with respect to the duration of a patient's stay in the intensive care unit and on the hospital ward. |
| Quality of life (SF-12) | Up to 90 days after surgery. | Comparison of mild (32°C) vs moderate (26°C) hypothermia in aortic hemiarch surgery with respect to the patient's quality of life measured using the Short Form (SF) 12 questionnaire. |
| Rates of Mediastinal re-exploration for bleeding | Up to 90 days after surgery. | Comparison of mild (32°C) vs moderate (26°C) hypothermia in aortic hemiarch surgery with respect to the rates of mediastinal re-exploration (re-operation) for bleeding. |
Countries
Canada, United States
Contacts
Primary ContactJehangir Appoo, MD
Backup ContactAlice Black, BSc
Outcome results
None listed