The Gender Specific Effect on the Results of Ascending Aortic Replacement

The aim of our study is to analyze the early and late results in men and women who underwent ascending aortic replacement in antegrade cerebral perfusion (ACP) with mild-to-moderate hypothermic circulatory arrest. Female gender is associated with poorer outcomes after surgical aorta replacement. Data on gender specific differences after ascending aortic replacement are conflicting.

Description of the procedures:

All surgical procedures will be performed via median sternotomy. During the aortic arch anastomosis, continuous, unilateral SACP using innominate artery will be employed. Unilateral SACP may be converted to bilateral ACP at the surgeon's discretion if adequate cerebral flows are not achieved or if there are concerns with cerebral oximetry measurements.

Once on CPB, the patient will be cooled to a nasopharyngeal (NP) temperature of either 26-32 °C. Rectal temperature with be monitored as an additional temperature sites. Unilateral SACP will only be initiated once the target temperature has been reached. SACP via the innominate artery will be commenced with target flows of 8-10 ml/kg/min and perfusion pressure of 60-80 mmHg. Perfusion adequacy will be evaluated using measurement of blood pressure in both radial arteries and cerebral oximetry using near-infrared spectroscopy (NIRS).

After completion of the aortic hemiarch replacement, CPB will be resumed and the patient re-warmed to 36 °C prior to coming off CPB, with a = 1 °C temperature difference between temperature monitoring sites (NP and rectal).

Intraoperative information will be collected from the anesthetic record, surgical notes and perfusion records. Intraoperative data collection will include total operative time, CPB time, cross-clamp time, hypothermic cardiac arrest time, uSACP time, lowest nasopharyngeal and rectal temperature, arterial pressure in both radial arteries, perfusion rate and perfusion pressure during both of CPB and unilateral SACP, lowest hemoglobin concentration (g/L) and hematocrit (%), acid-base indices, intraoperative red blood cell transfusion (units), highest dose/agent used for intraoperative inotrope or vasopressor support. Also during the surgery will be performed NIRS and BIS-monitoring(bispectral index).

Postoperative data will include valuation of following indicators: mortality (hospital mortality and death from any cause); neurological injury (TIA, stroke, delirium), MRI and CT-scan only in event of postoperative stroke; acute kidney injury (creatinine level prior and 1, 2, 4 postoperative day (POD), renal replacement therapy (dialysis); time of mechanical ventilation; re-exploration for bleeding, tamponade or other reasons; postoperative transfusion (packed red blood cells, platelets, fresh frozen platelets, cryoprecipitate); postoperative myocardial infarction (electrocardiogram and troponins); length of stay (intensive care unit and total hospital days).

Follow-up information will be collected using direct or phone contact with patients, relatives, or physicians.

Eligibility Criteria:
Inclusion Criteria:

* Patients with small ascending aortic aneurysm (5.0-5.5 cm)
* Elective procedure
* Able to provide written informed consent

Exclusion Criteria:

* Surgery for acute aortic dissection or emergent operations
* Refusal of surgical treatment
* Oncological disease (high degrees)
* Multiple organ failure