Charles D. Fraser

Cardiopulmonary bypass with profound hypothermia: An optimal preservation method for multiorgan procurement

Numerous techniques have been devised for the harvesting of individual organs during a multiorgan procurement operation. Cardiopulmonary bypass with profound hypothermia (PH) has been employed in successful harvesting of heart-lung, kidney, pancreas, and liver grafts. This report summarizes our experience using CPB-PH for the harvesting of multiple organs from 10 brain-dead donors during the period from July 1983 to January 1988. Organs harvested included 10 heart-lungs, 17 kidneys (3 kidneys were not harvested due to anatomy and elevated creatinine), 1 liver, and 1 pancreas. Mean ischemic time for the distantly procured heart-lung grafts was 281 +/- 10 min. Adequate pulmonary function, as assessed by arterial blood gases, was observed in each heart-lung recipient (mean PO2 was 119 +/- 46 mmHg, 164 +/- 47 mmHg, 130 +/- 30 mmHg, 114 +/- 26 mmHg at immediate post-CPB, 6 hr postop, 24 hr postop, and postextubation, respectively). Mean length of intubation was 34 +/- 8 hr. Mean creatinines of kidney recipients at days 2, 7, and current creatinine were 7.4 +/- 3.6 mg%, 3.6 +/- 2.4 mg%, and 1.6 +/- 0.66 mg%, respectively. Eight kidney recipients (47%) required dialysis, (2 patients required only a single dialysis). Ninety-four percent of the kidney transplant patients are alive, and 88% (15/17) have functioning kidneys. One liver and 1 pancreas were harvested during this time period. Preservation was satisfactory in both the pancreas (Johns Hopkins Hospital) and liver (Dr. Thomas Starzl, personal communication). The technique of CPB-PH has resulted in excellent function of heart-lung grafts. Follow-up of the transplanted kidneys, liver, and pancreas utilizing this technique shows equal or better function compared with standard techniques. This technique offers other advantages in addition to satisfactory multiorgan preservation. Placement of an unstable patient on CPB ensures adequate organ perfusion and allows for a gradual yet uniform cooling of all organ systems. Cooling to a core temperature of 10-15 degrees C requires 30 min, during which time preliminary intraabdominal and mediastinal dissection can be carried out. Following cessation of CPB and subsequent exsanguination, organs can be more easily dissected in a near-bloodless field. This technique does not preclude additional crystalloid organ flushing. Since multiorgan procurement occurs with virtually every donor, this technique may be the optimal method providing excellent preservation, ease of dissection, and better control of hemodynamics during the operation.

Donor core-cooling provides improved static preservation for heart-lung transplantation.

Twenty-three dairy calves underwent heart-lung allotransplantation after donor organs were procured using either donor core-cooling through cardiopulmonary bypass (CPB) or pulmonary artery flush (PAF) to assess which method provides optimal graft preservation. In Groups 1 (control) and 2, donors were cooled to 15 degrees C on CPB and organs were either immediately transplanted (Group 1) or stored in saline solution (4 degrees C) for 4 hours (Group 2) prior to transplantation. In Group 3, donors were pretreated with prostaglandin E1 prior to PAF with modified Euro-Collins solution. Organs were stored in saline solution (4 degrees C) for 4 hours and were then transplanted. Acute cardiopulmonary function following transplantation was assessed by the ratio of end-systolic pressure to end-systolic dimension, extravascular lung water (EVLW), lung compliance, arterial oxygenation, and lung biopsy. Cardiac function after the transplantation procedure was similar in all groups, but EVLW values and lung biopsy scores were worse after PAF. Arterial O2 tension appeared lower after PAF, but not significantly so. Core-cooling provides superior static preservation and thus improved graft function in the acute bovine model.

Effects of cyclosporine on cerebral blood flow and metabolism in dogs.

Neurological side effects associated with cyclosporine immunosuppressive therapy are generally believed to occur with CsA blood concentrations above the therapeutic range. The effects of high blood CsA levels on cerebral hemodynamics, metabolism, and electrophysiologic activity were studied in acute (no CsA prior treatment) and chronic (with CsA prior treatment) dogs. In acute animals, when parenteral CsA (10 mg/kg or 25 mg/kg) was administered intravenously (CsA blood level 2000–22,000 ng/ml), slight but significant time-dependent decreases in cerebral blood flow (CBF), prolongation of absolute latencies of somatosensory-evoked potential (SSEP), and brainstem auditory-evoked responses (BAER) were noted. In the CsA chronically administered animals (oral CsA 25 mg/kg/24 hr for 14 days, CsA blood level 1077 ng/ml), baseline cerebral physiologic parameters were normal, and the cerebral responses to further administration of CsA (25 mg/kg, CSA blood level 56,000 ng/ml) intravenously were similar to those of the acute animals. Animals given Cremophor EL, the solvent for parenteral CsA preparation, showed similar cerebral responses to those observed in animals given CsA. Thus this study showed that CsA, regardless of the dose given, whether chronically or acutely administered, or the solvent for CsA all induced similar cerebral physiologic responses. We suggest that the cerebral physiologic and functional changes associated with parenteral CsA administration were small and were likely caused by its solvent, Cremophor EL, rather than CsA itself. Furthermore on the basis of our results, it is unlikely that high blood CsA per se can account for neurological side effects that occur in immunosuppressed patients.

Acute Cholecystitis Preceding Mycotic Aortic Pseudoaneurysm in a Heart Transplant Recipient

Abstractu2002 Mycotic pseudoaneurysm is a rare complication after orthotopic heart transplantation (OHT). This case describes a middle‐aged OHT recipient who developed a mycotic pseudoaneurysm after an episode of acute cholecystitis. The region of involved aorta was effectively repaired using a patch of bovine pericardium and a brief period of hypothermic circulatory arrest.u2002(J Card Surg 2010;25:749‐751)

Duration of Left Ventricular Assist Device Support Does Not Impact Survival After US Heart Transplantation

BACKGROUNDnThe aim of this study was to determine whether the duration of left ventricular device support (LVAD) influenced outcomes after orthotopic heart transplantation in a modern, bridge to transplant national cohort.nnnMETHODSnThe United Network for Organ Sharing database, which has recently made pretransplant LVAD duration available, was queried for all adult bridge to transplant patients between January 2011 and December 2012. Three LVAD duration cohorts were generated, as follows: short (less than 90 days), intermediate (90 to 365xa0days), and prolonged (more than 365 days). Recipient,xa0donor, and transplant-specific characteristics were compared among the duration cohorts. Unadjusted short-term and long-term survivals were estimated with the Kaplan-Meier method. Risk-adjusted models were also constructed to determine the independent impact of device duration on mortality.nnnRESULTSnOf the 1,332 patients who met criteria for inclusion, 9.8% (nxa0= 130), 54.7% (nxa0= 729), and 35.5% (nxa0= 473) were classified as short, intermediate, and prolonged, respectively. Although the performance statusxa0across eachxa0cohort was similar at listing (pxa0= 0.38), more patients in the intermediate and prolonged cohortsxa0were considered functionally independent beforexa0orthotopic heart transplantation (32% and 37%, respectively, versus 18%; p < 0.001). Additionally, despite worse baseline renal function in the intermediate and prolonged cohorts relative to the short cohort (glomerular filtration rate, 57 and 57 versus 69, p < 0.001), there was noxa0difference in the incidence of new onset posttransplant renal failure (7% versus 10%, 9%, pxa0= 0.41). There was also no difference in 30-day survival (98%, 96%, 95%, pxa0= 0.51), 6-month survival (93%, 92%, 92%, pxa0= 0.93), orxa01-year survival (91%, 89%, 89%, pxa0= 0.78) across the cohorts. After risk adjustment, duration did not independently predict mortality at any timepoint.nnnCONCLUSIONSnIn the largest, non-industry sponsored study of a modern bridge to transplant cohort, we demonstrated that duration of LVAD support before orthotopic heart transplantation does not influence posttransplant morbidity or mortality. In subanalysis, support for 90 days or more is associated with improvements in pretransplant functional performance.

Pseudoaneurysm formation after valve sparing root replacement in children with Loeys-Dietz syndrome

Loeys‐Dietz syndrome (LDS) is an autosomal dominant connective tissue disorder predisposing patients to aneurysm formation and arterial dissection. Aortic root replacement is often performed prophylactically and valve‐sparing root replacement (VSRR) has become the procedure of choice. However, in these patients with connective tissue disorders, postoperative pseudoaneurysms may develop.

Surgical Closure of Patent Ductus Arteriosus in Premature Neonates Weighing Less Than 1,000 grams: Contemporary Outcomes:

Objective: The safety of surgical closure of patent ductus arteriosus (PDA) in very low birth weight premature neonates has been questioned because of associated morbidities. However, these studies are vulnerable to significant bias as surgical ligation has historically been utilized as “rescue” therapy. The objective of this study was to review our institutions’ outcomes of surgical PDA ligation. Methods: All neonates with operative weight of ≤1.00 kg undergoing surgical PDA ligation from 2003 to 2015 were analyzed. Records were queried to identify surgical complications, perioperative morbidity, and mortality. Outcomes included pre- and postoperative ventilator requirements, pre- and postoperative inotropic support, acute kidney injury, surgical complications, and 30-day mortality. Results: One hundred sixty-six preterm neonates underwent surgical ligation. One hundred twenty-one (70.3%) had failed indomethacin closure. One hundred sixty-four (98.8%) patients required mechanical ventilation prior to surgery. At 17 postoperative days, freedom from the ventilator reached 50%. Of 109 (66.4%) patients requiring prolonged preoperative inotropic support, 59 (54.1%) were liberated from inotropes by postoperative day 1. Surgical morbidity was encountered in four neonates (2.4%): two (1.2%) patients had a postoperative pneumothorax requiring tube thoracostomy, one (0.6%) patient had a recurrent laryngeal nerve injury, and one (0.6%) patient had significant intraoperative bleeding. The 30-day all-cause mortality was 1.8% (n = 3); no deaths occurred intraoperatively. Conclusion: In this retrospective investigation, surgical PDA closure was associated with low 30-day mortality and minimal morbidity and resulted in rapid discontinuation of inotropic support and weaning from mechanical ventilation. Given the safety of this intervention, surgical PDA ligation merits consideration in the management strategy of the preterm neonate with a PDA.

Cervical esophago-esophageal anastomosis

We describe our results with cervical esophagoesophageal anastomosis. This approach has been used with success in 4 patients. It has the advantage of avoiding esophagectomy in patients with benign disease and allows restoration of esophageal continuity in patients having limited options for esophageal replacement.

Coronary Button Pseudoaneurysms After Aortic Root Replacement in a Child With Loeys-Deitz Syndrome

Loeys-Deitz syndrome (LDS) is a connective tissue disorder characterized by aggressive aortopathy with a proclivity for aortic aneurysmal rupture and dissection. Prophylactic surgical intervention is often indicated to ameliorate risk of aneurysm rupture. Aortic root replacement involves excision of the coronary arteries from the aortic root with a button of surrounding aortic tissue and subsequent anastomosis of these buttons to the synthetic aortic graft. We report the case of a 16-year-old girl with LDS who developed pseudoaneurysms at the sites of previous coronary button implantation.

Tricuspid Valve Detachment in Ventricular Septal Defect Closure Does Not Impact Valve Function

BACKGROUNDnAlthough tricuspid valve detachment (TVD) facilitates improved exposure during transatrial ventricular septal defect (VSD) closure, few have analyzed the impact of TVD on long-term valve durability.nnnMETHODSnPediatric patients undergoing VSD closure at our institution from 1997 to 2013 were identified, and charts were retrospectively reviewed. Patients were separated into groups based on utilization of TVD. Propensity score matching was then performed using a nonparsimonious logistic regression model involving 7 variables. Primary outcome was residual TV dysfunction at long-term follow-up, defined as mild (2+) and moderate (3+) TV regurgitation (TR) on follow-up echocardiography. Secondary outcomes included postoperative atrioventricular dissociation, residual VSD, and reinterventions.nnnRESULTSnA total of 247 patients underwent VSD closure; 164 (66.4%) without TVD and 83 (33.6%) with TVD. Median follow-up time was 2,343 days (interquartile range, 1,237 to 3,963.5 days) in the group without TVD versus 1,606 days (interquartile range, 826 to 3,017 days) in those with TVD. After successfully matching 83 patients, 29 of 83 (34.9%) patients in the non-TVD group had mild TR versus 28 of 83 (33.7%) patients in the TVD group (pxa0= 0.87). 2 patients in the non-TVD group had moderate TR versus 1 patient in the TVD group at long-term follow-up. One patient in each group suffered transient atrioventricular block, but neither required pacemaker insertion.nnnCONCLUSIONSnTVD did not compromise long-term valve durability and did not impose increased morbidity. Patients who underwent TVD had a similar prevalence of mild TR to patients without TVD. Moderate TR was exceptionally rare in both groups. When exposure is difficult, TVD is a safe and effective technical adjunct.