Results of aortic arch repair with hypothermic circulatory arrest and retrograde cerebral perfusion

Clinical Predictors for Prolonged Intensive Care Unit Stay in Adults Undergoing Thoracic Aortic Surgery Requiring Deep Hypothermic Circulatory Arrest

OBJECTIVE

The purpose of this study was to describe clinical predictors for prolonged length of stay in the intensive care unit (PLOS-ICU) after adult thoracic aortic surgery requiring standardized deep hypothermic circulatory arrest (DHCA); and to determine the incidence of PLOS-ICU after DHCA, univariate predictors for PLOS-ICU, and multivariate predictors for PLOS-ICU.

STUDY DESIGN

A retrospective and observational study. PLOS-ICU was defined as longer than 5 days in the ICU.

STUDY SETTING

Cardiothoracic operating rooms and the ICU.

PARTICIPANTS

All adults requiring thoracic aortic repair with DHCA INTERVENTIONS: None.

MAIN RESULTS

The cohort size was 144. The incidence of PLOS-ICU was 27.8%. The mortality rate was 11.1%. Univariate predictors for PLOS-ICU were age, stroke, DHCA duration, vasopressor dependence >72 hours, mediastinal re-exploration for bleeding, and renal dysfunction. Multivariate predictors for PLOS-ICU were stroke, vasopressor dependence >72 hours, and renal dysfunction.

CONCLUSIONS

PLOS-ICU after DHCA is common. The identified multivariate predictors merit further hypothesis-driven research to enhance perioperative protection of the brain, kidney, and cardiovascular system.

Major Clinical Outcomes in Adults Undergoing Thoracic Aortic Surgery Requiring Deep Hypothermic Circulatory Arrest: Quantification of Organ-Based Perioperative Outcome and Detection of Opportunities for Perioperative Intervention

OBJECTIVE

The purpose of this study was to describe clinical outcome after adult thoracic aortic surgery requiring standardized deep hypothermic circulatory arrest (DHCA), to determine mortality and length of stay, neurologic outcome, cardiorespiratory outcome, and hemostatic and renal outcome after DHCA.

DESIGN

Retrospective and observational.

SETTING

Cardiothoracic operating rooms and intensive care unit (ICU).

PARTICIPANTS

All adults requiring thoracic aortic repair with DHCA.

INTERVENTIONS

None. The study was observational.

MAIN RESULTS

The cohort size was 110. All patients received an antifibrinolytic. The mortality rate was 8.2%. The mean length of stay was 6.8 days (ICU) and 14.0 days (hospital). The incidence of stroke was 8.1% and postoperative delirium was 10.9%. The rate of postoperative atrial fibrillation was 43.6%; 19.1% required postoperative mechanical ventilation longer than 72 hours. Chest tube drainage was 931 mL for the first 24 hours. Postoperative dialysis was required in 1.8% of patients. Renal dysfunction occurred in 40% to 50% of patients, depending on the definition.

CONCLUSIONS

The protocol for DHCA at the authors' institution is associated with superior or equivalent perioperative outcomes to those reported in the literature. This study identified the need for further quantification of the clinical outcomes after DHCA in order to prioritize outcome-based hypothesis-driven prospective intervention in DHCA.

Complex intimal flaps in acute aortic dissection

A 43-year-old man was emergently admitted and diagnosed as acute aortic dissection (Stanford type A). While being prepared for emergent operation he fell into hemodynamic hazard with repeated ventricular fibrillation and loss of consciousness. Massive aortic regurgitation and coronary disturbance due to a back-and-forth movement of an intimal flap through the aortic valve were the causes of the cardiogenic catastrophy. In addition, a completely torn intimal flap was intussuscepted into the origin of the brachiocephalic artery. This was thought to disturb the cerebral perfusion. Acute aortic dissection with such complex intimal flaps is very rare. In such cases cardiopulmonary bypass should be established to maintain the patient's cardiac function as soon as possible after diagnosis and the operation should be performed with sufficient brain protection.

Total aortic arch grafting via median sternotomy using integrated antegrade cerebral perfusion

BACKGROUND

In aortic arch grafting, antegrade cerebral perfusion prolongs the safe time of arch exclusion. However, there are the problems of cerebral embolism and distribution of the cerebral perfusion. We describe and analyze mortality and cerebral complications in patients undergoing total arch grafting using our refined technique.

METHODS

Between June 1994 and March 2002, 100 consecutive patients underwent total arch grafting through median sternotomy. There were 49 atherosclerotic aneurysms and 51 aortic dissections. Fifty-four patients were operated on an emergency basis because of rupture or acute type A dissection. We conducted total arch grafting using hypothermic antegrade cerebral perfusion from every cervical vessel. Carbon dioxide gas was added to the cerebral perfusion in order to inhibit the increase in the cerebral vascular resistance during hypothermic cerebral perfusion.

RESULTS

Hospital mortality was 4%. The causes of death were dysarrhythmia (n = 1), mesenteric necrosis (n = 1), and preoperative cardiac arrest (n = 2). On univariate analysis, preoperative shock and concomitant cardiac procedures were risk factors for hospital death. The rate of postoperative neurologic damage was 5%. Two patients suffered from cerebral infarction. Temporary neurologic dysfunction occurred in 3 patients. On univariate analysis, emergency surgery was a risk factor for postoperative neurologic damage. On multivariate analysis, there was no significant independent predictor of hospital mortality and neurologic damage. Actuarial survival at 96 months was 66.4 +/- 9.1%, and freedom from aortic accidents (reoperation, rupture, and cholesterol embolism) was 74.9 +/- 7.9%.

CONCLUSIONS

The early- and long-term results of total arch grafting using integrated antegrade cerebral perfusion were found to be satisfactory.

Determination of cerebral blood flow dynamics during retrograde cerebral perfusion using power M-mode transcranial Doppler

BACKGROUND

Retrograde cerebral perfusion (RCP) during profound hypothermic circulatory arrest has been used as an adjunct for cerebral protection for repairs of the ascending and transverse aortic arch. Transcranial Doppler ultrasound has been used to monitor cerebral blood flow during RCP with varying success. The purpose of this study was to characterize cerebral blood flow dynamics during RCP using a new mode of monitoring known as transcranial power motion-mode (M-mode) Doppler ultrasound.

METHODS

Data on pump-flow characteristics and patient outcomes were collected prospectively for patients undergoing ascending and transverse aortic arch repair. Retrograde cerebral perfusion during profound hypothermic circulatory arrest was used for all operations. Intraoperative cerebral blood flow dynamics were monitored and recorded using transcranial power M-mode Doppler ultrasound.

RESULTS

Between August 2001 and March 2002, we used transcranial power M-mode Doppler ultrasound monitoring for 40 ascending and transverse aortic arch repairs during RCP. Mean RCP time was 32.2 +/- 13.8 minutes. Mean RCP pump flow and RCP peak pressure for identification of cerebral blood flow were 0.66 +/- 0.11 L/min and 31.8 +/- 9.7 mm Hg, respectively. Retrograde cerebral blood flow during RCP was detected in 97.5% of cases (39 of 40 patients) with a mean transcranial power M-mode Doppler ultrasound flow velocity of 15.5 +/- 12.3 cm/s. In the study group, 30-day mortality was 10.0% (4 of 40 patients). The incidence of stroke was 7.6% (3 of 40 patients); the incidence of temporary neurologic deficit was 35.0% (14 of 40 patients).

CONCLUSIONS

Transcranial power M-mode Doppler ultrasound consistently demonstrated retrograde middle cerebral artery blood flow during RCP. Transcranial power M-mode Doppler ultrasound can provide optimal RCP with individualized settings of pump flow.