Modified Perfusion for Neonatal Aortic Arch Reconstruction

Study Overview
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Brief Summary
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Even though the lower part of the body does receive some blood supply during Cardiopulmonary Bypass(CPB) surgery, it may not be enough. As a result of this lowered blood supply, there are complications associated with CPB and clamping of the aorta. These include complications with the stomach, intestines and kidneys. The hypotheses of this study are that increased lower body perfusion during aortic arch reconstruction will decrease intestinal ischemia and the incidence of necrotizing enterocolitis, improve renal function in the postoperative period, and shorten both intensive care unit and hospital length of stay. The purpose of this research study is to provide the lower part of the body and its organs with possibly more blood supply with a modified form of cardiopulmonary bypass and see if this additional blood supply helps to decrease complications of the kidney, stomach and intestines.

Detailed Description
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As the aorta is repaired, the child has no circulation to the body or brain. While short periods of circulatory arrest were well tolerated, a modified technique called selective cerebral perfusion was developed to maintain blood flow to the brain during aortic repairs so as to allow for less hurried repairs with less concern over brain ischemia and injury. Selective cerebral perfusion is designed to provide flow to the brain via the right carotid artery and collateral intracranial vessels while the aortic arch is isolated for repair. It is felt that collateral vessels also allow some perfusion of the lower body, but the adequacy of lower body perfusion during selective cerebral perfusion has not been well documented. While it is clear that some blood reaches the lower body, the incidence of renal and gastrointestinal complications following cardiac repairs involving aortic arch reconstructions remains significant. The goal of this proposal is to evaluate a simple modification of the standard selective cerebral perfusion protocol designed to increase perfusion to the lower body during aortic arch reconstructions. Essentially all children who undergo aortic arch reconstruction at Egleston hospital have either a femoral or umbilical artery catheter in place for routine monitoring. During selective cerebral perfusion, the descending thoracic aorta is clamped, so the lower body arterial line is not a useful monitor at that point. We propose to connect a pressure line from the cardiopulmonary bypass circuit to the lower body arterial catheter, allowing for increased perfusion of the lower body through the femoral/umbilical arterial catheter during selective cerebral perfusion We will monitor simultaneous near infra-red spectroscopy of the brain, flank, and thigh to determine the adequacy of oxygen delivery to the brain, kidney, and lower body musculature during the procedure. Near infra-red spectroscopy provides a measure of the oxygenation of hemoglobin in arterial, capillary, and venous blood within the path of an infra-red sensor. Blood samples will be collected before skin incision, at the end of the procedure, and at 3, 12, and 24 hours after arrival to the intensive care unit. Intestinal fatty acid binding protein (i-FABP) and c-reactive protein (CRP) serum levels will be measured at each timepoint as markers of intestinal ischemia and generalized inflammation respectively. The incidence of documented or suspected necrotizing enterocolitis prior to hospital discharge and the time required to achieve full enteral feeds will be recorded. Renal function will be assayed by the maximal change from preoperative to postoperative serum creatinine, normalized urine output per 12 hour period following surgery, total diuretic dose per day, and daily creatinine clearance for the first 3 days after surgery.

Official Title
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Evaluation of a Modified Perfusion Strategy for Neonatal Aortic Arch Reconstruction: Does Perfusing the Lower Body During Arch Repair Help?

Conditions
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Aortic Arch Hypoplasia or Atresia

Intervention / Treatment
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* Procedure: Modified Selective Cerebral Perfusion


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Diagnosis including aortic coarctation, arch hypoplasia, or interrupted aortic arch which requires cardiopulmonary bypass for repair age less than 1 year parental consent for participation Exclusion Criteria: prior aortic arch operations emergency operation operating surgeon decides that selective cerebral perfusion is not indicated Documented renal insufficiency (creatinine > 2.0) or evidence of bowel ischemia prior to surgery

Ages Eligible for Study
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Maximum Age: 1 Year

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: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| No Intervention: Control<br>Arm 1 is the control arm. This arm will receive the standard cardiopulmonary bypass circuit. | |
| Active Comparator: Experimental<br>This arm is the modified selective perfusion arm. This arm will receive the modified cardiopulmonary circuit. | Procedure: Modified Selective Cerebral Perfusion<br>* Modified Selective perfusion is a cardiopulmonary bypass circuit that has been modified to allow blood flow to the lower body as well as the upper body while the surgery is being performed.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Intestinal Fatty Acid Binding Protein and C-reactive Protein |  | Baseline and 0, 3, 12, and 24 hours after surgery | 
| iFAB Post-op | intestinal fatty acid binding protein level immediately postop | Immediate postop | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cerebral and Lower Body Near Infra-red Spectroscopy Measures |  | 24 hours | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Pediatrics, Selective Cerebral Perfusion, Renal Complications, Gastrointestinal Complications, Aortic Arch Reconstruction, Modified Perfusion, Cardiopulmonary Bypass, Cardiac Defects, intestinal ischemia, necrotizing entercolitis, Near Infra-red spectroscopy, Creatinine, C-reactive protein levels