Retrograde inferior vena caval perfusion for total aortic arch replacement surgery: a randomized pilot study.

OBJECTIVES: Antegrade cerebral perfusion (ACP) under moderate hypothermic circulatory arrest is used during total aortic arch replacement surgery (TARS) in patients with acute type A aortic dissection, but it is associated with high mortality and morbidity. We hypothesized that combining ACP with retrograde inferior vena caval perfusion (RIVP) improves outcomes. METHODS: This pilot study was prospective, randomized, controlled and assessor-blinded. Patients scheduled for TARS were randomly treated with either ACP or RIVP + ACP. The primary outcome was a composite of mortality and major complications including paraplegia, postoperative renal failure, severe liver dysfunction, and gastrointestinal complications. Secondary outcomes included neurological complications, length of intubation and requirement of blood products. RESULTS: A total of 76 patients were recruited (n = 38 per group). Primary outcome occurred in 23 patients (61%) in the ACP group and 16 (42%) in the RIVP + ACP group (OR: 0.60, 95% CI: 0.21-1.62; p = 0.31). There was a lower incidence of transient neurological deficits in the RIVP + ACP group (26% vs. 58%, OR: 0.26; 95% CI: 0.10-0.67,p = 0.006;). The RIVP + ACP group underwent shorter intubation (25 vs 47 h, p = 0.022) and required fewer blood products (red cells, 3.8 units vs 6.5 units, p = 0.047; platelet: 2.0 units vs 2.0 units, p = 0.023) compared with the ACP group. CONCLUSIONS: RIVP + ACP may be associated with lower incidence of transient neurological deficits, shorter intubation and less blood transfusion requirement than ACP alone during TARS. Multi-center, randomized trials with larger samples are required to determine whether RIVP + ACP is associated with lower rates of mortality and major complications. TRIAL REGISTRATION: Pilot study of a RCT registered in clinicaltrials.gov (NCT03607786), Registered 30 July, 2018-Retrospectively registered, https://clinicaltrials.gov/ct2/show/NCT03607786 .

A Contemporary Meta-Analysis of Antegrade versus Retrograde Cerebral Perfusion for Thoracic Aortic Surgery.

OBJECTIVE: To determine which of antegrade and retrograde cerebral perfusion (ACP and RCP) surpasses for a reduction in postoperative incidence of neurological dysfunction and all-cause death in thoracic aortic surgery, we performed a meta-analysis of contemporary comparative studies. METHODS: MEDLINE, EMBASE, and the Cochrane Central Register of Controlled Trials were searched from January 2010 to June 2017. For each study, data regarding the endpoints in both the ACP and RCP groups were used to generate odds ratios (ORs) and 95% confidence intervals (CIs). Study-specific estimates were combined using inverse variance-weighted averages of logarithmic ORs in the fixed-effect model. RESULTS: We identified and included 19 eligible studies with a total of 15,365 patients undergoing thoracic aortic surgery by means of ACP (a total of 7,675 patients) or RCP (a total of 7,690 patients). Pooled analysis demonstrated no statistically significant differences in postoperative incidence of stoke (17 studies enrolling a total of 9,421 patients; OR, 0.92; 95% CI, 0.79-1.08; p = 0.32) and mortality (16 studies including a total of 14,452 patients; OR, 1.07; 95% CI, 0.90-1.26; p = 0.46) between ACP and RCP, whereas a trend toward a significant reduction in incidence of temporary neurological dysfunction (TND) for ACP (12 studies enrolling a total of 7922 patients; OR, 0.85; 95% CI, 0.69-1.04; p = 0.12) was found. CONCLUSION: In thoracic aortic surgery, postoperative incidence of stroke and mortality was similar between ACP and RCP, whereas a trend toward a reduction of TND incidence existed in ACP.

Moderate Hypothermic Circulatory Arrest (≥ 28°C) with Selective Antegrade Cerebral Perfusion for Total Arch Replacement with Frozen Elephant Trunk Technique.

OBJECTIVES: The optimal hypothermic level during circulatory arrest in aortic arch surgery remains controversial, particularly in frozen elephant trunk (FET) procedures. We describe herein our experience for total arch replacement with FET technique under moderate systemic hypothermic circulatory arrest (≥ 28°C) during selective antegrade cerebral perfusion. METHODS: Between January 2009 and January 2016, 38 consecutive patients underwent elective total arch replacement for various aortic arch pathologies with FET technique using the E-vita Open hybrid prosthesis (Jotec GmbH, Hechingen, Germany). Selective unilateral or bilateral cerebral perfusion under moderate systemic hypothermic circulatory arrest (28.7°C ± 0.5°C) was used in all patients. Minimally invasive total arch replacement with FET via partial upper sternotomy was performed in 15 patients (39%) and in the remaining 23 patients (61%) via full sternotomy. Mean late follow-up was 3 ± 2 years and was 98% complete. Clinical data were prospectively entered into our institutional database. RESULTS: Cardiopulmonary bypass time accounted for 198 ± 58 minutes and the myocardial ischemic time 109 ± 29 minutes. Selective antegrade cerebral perfusion time was 55 ± 6 minutes. Lower body circulatory arrest time was 39 ± 11 minutes. Unilateral cerebral perfusion was performed in 31 patients (82%), and bilateral in 7 patients (18%). Intensive care unit stay was 4 ± 3 days. Thirty-day mortality was 5% (n = 2). Late survival at 3 years was 87 ± 3%. Two patients (5%) required reexploration for bleeding. Patients were discharged after a hospital length of stay of 7 ± 2 days. Postoperative permanent neurologic complication occurred in two patients (5%). Three patients (8%) experienced a transient neurologic disorder. New transient renal replacement therapy was necessary in three patients (8%). No spinal cord injury was noted. CONCLUSIONS: Our data suggest that moderate systemic hypothermic circulatory arrest (≥ 28°C) in combination with antegrade cerebral perfusion can safely be applied for total aortic arch replacement with FET and offers sufficient neurologic and visceral organ protection.

Evaluation of quality of kidneys from donation after circulatory death/expanded criteria donors by parameters of machine perfusion.

AIM: To investigate whether the parameters of machine perfusion could predict the quality of kidneys from donation after circulatory death (DCD) donors and expanded criteria donors (ECD). METHODS: Fifty-eight kidneys from DCD/ECD donors were harvested in our hospital from July 2011 to August 2014. All kidneys were preserved with machine perfusion (Life Port), and parameters of machine perfusion were collected. All kidneys were biopsied before transplantation. The primary endpoints were delayed graft function (DGF), graft loss and patient death. RESULTS: After kidney transplantation, 26 patients (44.8%) had DGF. We chose 1 h RI as a predictive parameter to predict DGF after transplant, and made the ROC curve. The ROC curve showed that 1 h RI = 0.4 was the best cut-off point for predicting DGF after transplant. The sensitivity was 61.54%, and the specificity was 81.25%. Fifty-eight recipients were divided into two groups according to 1 h RI of machine perfusion. 22 cases in high RI group (RI > 0.4) and 36 cases in low RI group (RI ≤0.4). DGF rate was significantly higher in the high RI group (72.7% vs. 27.8%). One year serum creatinine levels were also significantly higher in the high RI group (P < 0.05). Acute rejection rate and 1 year graft and patient survival were comparable. CONCLUSIONS: One hour RI of machine perfusion is associated with DGF and 1 year graft function in DCD/ECD kidney transplantation, and may be a non-invasive tool for evaluating quality of DCD/ECD kidneys.

Adjunct Perfusion Branch for Reduction of Spinal Cord Ischemia in the Endovascular Repair of Thoracoabdominal Aortic Aneurysms.

BACKGROUND: To analyze utilization of a perfusion branch for temporary sac perfusion to reduce the spinal cord ischemia (SCI) in the endovascular repair of thoracoabdominal aortic aneurysms (TAAAs). METHODS: Between January 2012 and August 2016, 30 patients (18, men; median age 72 years) were treated for TAAAs with total endovascular repair using customized branched/fenestrated endografts in our institution. The median aneurysm size was 6.6 cm. Types of TAAA were: type I, 9 (30%), type II, 5 (16.6%), type III, 4 (13.3%), type IV, 6 (20%), and type V, 6 (20%). Ten patients received a perfusion branch to create an intentional endoleak, which was occluded with vascular plugs in mean interval time of 8.2 weeks (range: 6-10). Staged procedure and automated cerebrospinal fluid drainage were used in 23 (77%) and 24 (80%) patients, respectively. RESULTS: The technical success was 97%; 107 renovisceral target vessels were revascularized (32 fenestrations, 75 branches). At the time of the planned reinterventions, the mean arterial pressure (MAP) gradients were measured between the temporarily perfused aneurysm sac and the aortic endografts, and they were significantly higher (mean gradients 42.5 ± 10 mm Hg; range: 30-60) within the aortic grafts. The in-hospital and 30-day mortality was 3.3%. The incidence of postoperative SCI was 3/20 (15%) in the standard group and 0% in the group of the perfusion branch (p = 0.28). The mean follow-up was 12 months (range: 2-51). CONCLUSION: We experience that the use of a dedicated perfusion branch is feasible and may serve as protective adjunct to reduce the risk of SCI in endovascular treatment of TAAA. The risk of rupture in interval appears to be low. Larger series and multicenter studies are warranted to corroborate these results.

Is More than One Hour of Selective Antegrade Cerebral Perfusion in Moderate-to-Mild Systemic Hypothermic Circulatory Arrest for Surgery of Acute Type A Aortic Dissection Safe?

OBJECTIVES: Surgery for acute type A aortic dissection (AAD) remains a surgical challenge with considerable risk of morbidity and mortality. Antegrade cerebral perfusion (ACP) has been popularized, offering a more physiologic method of brain perfusion during complex aortic arch repair, often necessary in setting of AAD. The safe limits of this approach under moderate-to-mild systemic hypothermic circulatory arrest (≥ 28°C) are yet to be defined. Thus, the current study investigates our clinical results after surgical treatment for AAD in patients with a selective ACP and systemic circulatory arrest time of ≥ 60 minutes in moderate-to-mild hypothermia (≥ 28°C). METHODS: Between January 2000 and April 2016, 63 consecutive patients underwent surgical treatment for AAD employing selective ACP during moderate-to-mild systemic hypothermia (≥ 28°C) with prolonged ACP and circulatory arrest times. Patients' mean age was 59 ± 15 years, and 39 patients (62%) were men. Hemiarch replacement and total arch replacement were performed in 13 (21%) and 50 (79%) patients, respectively. Frozen elephant trunk, arch light, and elephant trunk technique were performed in nine (14%), six (10%), and three patients (5%), respectively. Clinical data were prospectively entered into our institutional database. Mean late follow-up was 6 ± 4 years and was 98% complete. RESULTS: Cardiopulmonary bypass time accounted for 245 ± 81 minutes and the myocardial ischemic time accounted for 140 ± 43 minutes. Mean duration of ACP was 74 ± 12 minutes. The mean lowest core temperature accounted for 28.9 ± 0.8°C. Unilateral ACP was performed in 44 patients (70%); bilateral ACP was used in the remaining 19 patients (30%). Intensive care unit stay reached 6 ± 5 days. New onset of acute renal failure requiring hemofiltration was observed in 8% of patients (n = 5). New postoperative permanent neurologic deficits were found in five patients (8%) and transient neurologic deficits in six patients (10%). There was one case of paraplegia. Thirty-day mortality and in-hospital mortality were 8 (n = 5) and 11% (n = 7), respectively. Overall survival at 5 years was 76 ± 9%. CONCLUSION: Our preliminary data suggest that selective ACP during moderate-to-mild systemic hypothermic circulatory arrest (≥ 28°C) can safely be applied for more than 1 hour even in the setting of AAD.

Arterial protocol including prophylactic distal perfusion catheter decreases limb ischemia complications in patients undergoing extracorporeal membrane oxygenation.

OBJECTIVE: Venoarterial extracorporeal membrane oxygenation (ECMO) is a salvage therapy in patients with severe cardiopulmonary failure. Owing to the large size of the cannulas inserted via the femoral vessels (≤24-F) required for adequate oxygenation, this procedure could result in significant limb ischemic complications (10%-70%). This study evaluates the results of a distal limb perfusion arterial protocol designed to reduce associated complications. METHODS: We conducted a retrospective institutional review board-approved review of consecutive patients requiring ECMO via femoral cannulation (July 2010-January 2015). To prevent arterial ischemia, a distal perfusion catheter (DPC) was placed antegrade into the superficial femoral artery and connected to the ECMO circuit. Limb perfusion was monitored via near-infrared spectroscopy (NIRS) placed on both calves. Decannulation involved open repair, patch angioplasty, and femoral thrombectomy as needed. RESULTS: A total of 91 patients were placed on ECMO via femoral arterial cannula (16-F to 24-F) for a mean duration of 9 days (range, 1-40 days). A percutaneous DPC was inserted prophylactically at the time of cannulation in 55 of 91 patients, without subsequent ischemia. Of the remaining 36 patients without initial DPC placement, 12 (33% without DPC) developed ipsilateral limb ischemia related to arterial insufficiency, as detected by NIRS and clinical findings. In these patients, the placement of a DPC (n = 7) with or without a fasciotomy, or with a fasciotomy alone (n = 4), resulted in limb salvage; only one patient required subsequent amputation. After decannulation (n = 7), no patients had further evidence of limb ischemia. Risk factors for the development of limb ischemia identified by categorical analysis included lack of DPC at time of cannulation and ECMO cannula size of less than 20-Fr. There was a trend toward younger patient age. Overall ECMO survival rate was 42%, whereas survival in patients with limb ischemia was only 25%. CONCLUSIONS: Limb ischemia complications from ECMO may be decreased by prophylactic placement of an antegrade DPC. Without DPC, continuous monitoring using NIRS may identify limb ischemia, which can be treated subsequently with DPC and or fasciotomy.

Efficacy of Distal Perfusion Cannulae in Preventing Limb Ischemia During Extracorporeal Membrane Oxygenation: A Systematic Review and Meta-Analysis.

To date, no consensus exists regarding indication, technique, or efficacy of distal perfusion cannulae (DPC) in preventing limb ischemia among patients receiving venoarterial extracorporeal membrane oxygenation (VA-ECMO). We aim to examine the available literature and report association between DPC and risk of limb ischemia. PubMed/Medline, Scopus, Cochrane Central Register of Controlled Trials, Google Scholar, and bibliographies of included studies were searched from database inception until August 2016. Original studies describing the DPC placement technique and incidence of limb ischemia following DPC placement among VA-ECMO patients were included for systematic review. Studies with a comparison group of patients without DPC were included for meta-analysis. Two authors independently screened title/abstracts, reviewed full texts, and extracted data from the eligible studies. Meta-analysis was performed using the Mantel-Haenszel method under a random-effects model. Statistical heterogeneity was examined with the I2 statistic (RevMan Version 5.3). Of 542 title/abstracts screened, 62 full text articles were selected for review, yielding 22 retrospective observational studies, for a total of 779 patients with 132 limb ischemia events. There was significant variation in DPC indication, cannula type, and placement technique among the studies. Compared to no DPC, the presence of a DPC was associated with at least a 15.7% absolute reduction in the incidence of limb ischemia (9.74 vs. 25.42%; risk ratio 0.41; 95% confidence interval 0.26-0.65, P < 0.01; heterogeneity statistic I2 = 28%). There was no statistically significant difference in mortality in the pooled dataset comparing DPC versus no DPC. In adults treated with VA-ECMO, DPC placement was associated with a lower incidence of limb ischemia. Currently no consensus guidelines exist regarding indication for DPC placement. Given the association described in this analysis, future prospective trials are warranted to establish a causal relationship and optimal technique for the use of DPC in patients treated with VA-ECMO.

The Risk of Neurological Dysfunctions after Deep Hypothermic Circulatory Arrest with Retrograde Cerebral Perfusion.

OBJECTIVE: Retrograde cerebral perfusion (RCP) is a brain protection technique that is adopted generally for anticipated short periods of deep hypothermic circulatory arrest (DHCA). However, the real impact of this technique on cerebral protection during DHCA remains a controversial issue. METHODS: For 344 (59.5%) of 578 consecutive patients (mean age, 66.9 ± 10.9 years) who underwent cardiovascular surgery under DHCA at the present authors' institution (1999-2015), RCP was the sole technique of cerebral protection that was adopted in addition to deep hypothermia. Surgery of the thoracic aorta was performed in 95.9% of these RCP patients; in 92 cases there was an aortic arch involvement. Outcomes were reviewed retrospectively. The focus was on postoperative neurological dysfunctions. RESULTS: There were 33 (9.6%) in-hospital deaths. Thirty-one (9%) patients had permanent neurological dysfunctions and 66 (19.1%) transitory neurological dysfunctions alone. Age older than 74 years (odds ratio [OR], 1.88, P = .023), surgery for acute aortic dissection (OR, 2.57; P = .0009), and DHCA time longer than 25 minutes (OR, 2.44; P = .0021) were predictors of neurological dysfunctions. The 10-year nonparametric estimate of freedom from all-cause death was 61.8% (95% confidence interval, 57.8%-65.8%). Permanent postoperative neurological dysfunctions were risk factors for cardiac or cerebrovascular death (hazard ratio, 2.6; P = .039) even after an adjusted survival analysis (P < .04). CONCLUSIONS: According to the study findings, RCP, in addition to deep hypothermia, combines with a low risk of neurological dysfunctions provided that DHCA length is 25 minutes or less. Permanent postoperative neurological dysfunctions are predictors of poor late survival.

A systematic review and meta-analysis of cold in situ perfusion and preservation for pancreas transplantation.

BACKGROUND: This study aimed to identify the most effective solution for in situ perfusion/preservation of the pancreas in donation after brain death donors, in addition to optimal in situ flush volume(s) and route(s) during pancreas procurement. METHODS: Embase, Medline and Cochrane databases were utilized (1980-2017). Articles comparing graft outcomes between two or more different perfusion/preservation fluids (University of Wisconsin (UW), histidine-tryptophan-ketoglutarate (HTK) and/or Celsior) were compared using random effects models where appropriate. RESULTS: Thirteen articles were included (939 transplants). Confidence in available evidence was low. A higher serum peak lipase (standardized mean difference 0.47, 95% CI 0.23-0.71, I2 = 0) was observed in pancreatic grafts perfused/preserved with HTK compared to UW, but there were no differences in one-month pancreas allograft survivals or early thrombotic graft loss rates. Similarly, there were no significant differences in the rates of graft pancreatitis, thrombosis and graft survival between UW and Celsior solutions, and between aortic-only and dual aorto-portal perfusion. CONCLUSION: UW cold perfusion may reduce peak serum lipase, but no quality evidence suggested UW cold perfusion improves graft survival and reduces thrombosis rates. Further research is needed to establish longer-term graft outcomes, the comparative efficacy of Celsior, and ideal perfusion volumes.

Postoperative renal failure in thoracoabdominal aortic aneurysm repair with simple cross-clamp technique and 4°C renal perfusion.

OBJECTIVE: Acute renal failure (ARF) is reported in up to 12% of patients after thoracoabdominal aortic aneurysm (TAAA) repair with assisted circulation. ARF increases mortality, reduces quality of life, and increases length of hospital stay. This study analyzes ARF after TAAA repair done without assisted circulation. METHODS: A retrospective analysis of all patients treated for TAAA from 2000 to 2013 was performed using a concurrently maintained, institutionally approved database. All surgeries used simple cross-clamp technique, with moderate systemic hypothermia (32°-33°C) and renal artery perfusion with 4°C solution. Serum creatinine concentration was measured preoperatively and 1 day, 3 days, 7 days, and 30 days after surgery, and Cockcroft-Gault estimated glomerular filtration rate (eGFR) was calculated. Kidney injury was classified by RIFLE (Risk, Injury, Failure, Loss of kidney function, End-stage renal disease) eGFR criteria. Changes in eGFR, kidney injury, ARF, dialysis, length of stay, mortality, and risk factors for ARF were analyzed with SAS-JMP software (SAS Institute, Cary, NC) for univariate analysis and multivariate modeling. RESULTS: From 2000 to 2013, 455 patients had TAAA surgery; 116 (25.5%) were acute. Mean preoperative eGFR was 62.3 mL/min. Mean renal ischemia time was 58.9 minutes. Eighteen patients (4%) had ARF; nine (2%) required temporary dialysis, and three (0.66%) required permanent dialysis. In univariate analysis, age, renal ischemia time, acuity, baseline eGFR, previous aortic surgery, surgical blood loss, and return to operating room for bleeding complications were significant for ARF (P < .05). Sex, aneurysm extent by Crawford type, cardiac index and mean arterial pressure after reperfusion, and use of loop diuretics were not significant for ARF. In a stepwise deletion model, acute (P = .0377), previous aortic surgery (P = .0167), return to operating room (P = .0213), and age (P = .0478) were significant for ARF. Surgical blood loss (P = .0056) and return to operating room (P = .0024) were significant for postoperative dialysis in multivariate analysis. Only surgical blood loss was significant for permanent dialysis in a multivariate model (P = .0331). CONCLUSIONS: Very low ARF after TAAA repair can be achieved by simple cross-clamp technique with moderate systemic hypothermia and profound renal cooling. Age, preoperative eGFR, previous aortic surgery, return to operating room, and surgical blood loss were significant for ARF. Return to operating room for bleeding and surgical blood loss were significant for dialysis. Baseline eGFR <30 mL/min and postoperative dialysis were significant for mortality. Most patients with ARF, even those with temporary dialysis after TAAA repair, recover renal function to near preoperative levels.

Similar cerebral protective effectiveness of antegrade and retrograde cerebral perfusion during deep hypothermic circulatory arrest in aortic surgery: a meta-analysis of 7023 patients.

In aortic arch surgery, deep hypothermic circulatory arrest (DHCA) combined with cerebral perfusion is employed worldwide as a routine practice. Even though antegrade cerebral perfusion (ACP) is more widely used than retrograde cerebral perfusion (RCP), the difference in benefit and risk between ACP and RCP during DHCA is uncertain. The purpose of this meta-analysis is to compare neurologic outcomes and early mortality between ACP and RCP in patients who underwent aortic surgery during DHCA. PubMed, EMBASE, and the Cochrane Library were searched using the key words "antegrade," "retrograde," "cerebral perfusion," "cardiopulmonary bypass," "extracorporeal circulation," and "cardiac surgery" for studies reporting on clinical endpoints including early mortality, stroke, temporary neurologic dysfunction (TND), and permanent neurologic dysfunction (PND) in aortic surgery requiring DHCA with ACP or RCP. Heterogeneity was analyzed with the Cochrane Q statistic and I(2) statistic. Publication bias was tested with Begg's funnel plot and Egger's test. Thirty-four studies were included in this meta-analysis, with 4262 patients undergoing DHCA + ACP and 2761 undergoing DHCA + RCP. The overall pooled relative risk for TND was 0.722 (95% CI = [0.579, 0.900]), and the z-score for overall effect was 2.9 (P = 0.004). There was low heterogeneity (I(2) = 18.7%). The analysis showed that patients undergoing DHCA + ACP had better outcomes than those undergoing DHCA + RCP in terms of TND, while there were no significant differences between groups in terms of PND, stroke, and early mortality. This meta-analysis indicates that DHCA + ACP has an advantage over DHCA + RCP in terms of TND, while the two methods show similar results in terms of PND, early mortality, and stroke.

Hypothermic, initially oxygen-free, controlled limb reperfusion for acute limb ischemia.

BACKGROUND: Controlled limb reperfusion has been shown to prevent the deleterious effects of ischemia-reperfusion (IR) syndrome following revascularization of acute limb ischemia (ALI). To reduce the production of cell-toxic oxygen-free radicals, we have established a new initially oxygen-free, hypothermic, heparin-coated perfusion and hemofiltration system and report on our first results. METHODS: In a retrospective single-center study, controlled limb reperfusion was applied in 36 patients (64.7 ± 15 years) with ALI of category IIA to III (33.7 ± 20.7 hr ischemic time). 52.8% had central (aortic and bifurcation) and 47.2% had peripheral (common iliac artery and distal) vascular occlusions. The common femoral artery and vein were cannulated, and a hypothermic (22°C), initially oxygen-free, potassium-free ringer's solution was perfused using a heparin-coated extracorporeal membrane oxygenation (ECMO) and hemofiltration system with low-dose heparinization. Thirty-day mortality, clinical recovery of neurological dysfunction, limb amputation, and fasciotomy rate were analyzed. Laboratory parameters associated with ischemia and IR injury were determined. RESULTS: Average perfusion time was 94 ± 35 min. Thirty-day mortality was 27.8%. 55.5% of patients showed complete recovery of motor and sensory dysfunction. A total of 27.8% of patients developed a compartment syndrome and required fasciotomy. Lower leg amputation was necessary in 11.1% of patients. Lactate levels were reduced in ischemic limbs by 25.3% within 60 min (P < 0.05). Preoperative negative base excess of -1.96 ± 0.96 mmol/L was equalized after 12 hr (P < 0.05), while pH stayed balanced at 7.4. Serum potassium stayed within normal limits throughout 24 hr, and therefore systemic hyperkalemia was prevented and imminent metabolic acidosis was corrected. CONCLUSIONS: An initially oxygen-free, hypothermic, heparin-coated ECMO counteracts local and systemic effects of IR injury. Reduced mortality and morbidity might result from this new treatment, although this could not be conclusively proven in our study. A prospective, randomized controlled trial is needed to prove superiority of this new concept.

Efficacy of right axillary artery perfusion for antegrade cerebral perfusion in open total arch repair.

OBJECTIVE: Right axillary artery (RAxA) perfusion was introduced for selective antegrade cerebral perfusion in total aortic arch repair to prevent cerebral embolism derived from arterial cannulation. However, the strategic benefits and long-term results regarding the cannulation site remain controversial. We retrospectively compared the outcomes between propensity score-matched patients with and without using RAxA cannulation. METHODS: Between 2006 and 2012, 260 consecutive patients underwent total arch repair with antegrade cerebral perfusion and moderate hypothermia at a single institution. RAxA cannulation was added in 142 patients (54.6%), and 70 propensity score-matched pairs were obtained. RESULTS: There were no significant differences in 30-day (2.9% [2 of 70] vs 5.7% [4 of 70]; P = .415 and in-hospital death (5.7% [4 of 70] vs 5.7% [4 of 70]; P = 1.000) between matched pairs. Although there was no significant difference in the occurrence of postoperative stroke (8.6% [6 of 70] vs 8.6% [6 of 70]; P = 1.000), the new rate of new occurrence of postoperative paraparesis was lower in patients with RAxA perfusion (0% [0 of 70] vs 4.3% [3 of 70]; P = .067). With a mean follow-up period of 1057 ± 686 days, the overall 5-year survival was 90.6% and was 89.6% for patients with RAxA perfusion. Thee difference in survival between patients with and without RAxA perfusion was not significant. CONCLUSIONS: RAxA perfusion is a useful option for total aortic arch repair, and the midterm outcomes were satisfactory. However, RAxA perfusion did not completely prevent stroke in patients with an atherothrombotic aorta.

Normothermic ex vivo allograft blood perfusion in clinical heart transplantation.

BACKGROUND: Cold ischemia associated with cold static storage is an independent risk factor for primary allograft failure and survival of patients after orthotopic heart transplantation. The effects of normothermic ex vivo allograft blood perfusion on outcomes after orthotopic heart transplantation compared to cold static storage have been studied. METHODS: In this prospective, nonrandomized, single-institutional clinical study, normothermic ex vivo allograft blood perfusion has been performed using an organ care system (OCS) (TransMedics, Andover, MA, USA). Included were consecutive adult transplantation patients who received an orthotopic heart transplantation (oHTx) without a history of any organ transplantation, in the absence of a congenital heart disorder as an underlying disease and not being in need of a combined heart-lung transplantation. Furthermore, patients with fixed pulmonary hypertension, ventilator dependency, chronic renal failure, or panel reactive antibodies >20% and positive T-cell cross-matching were excluded. Inclusion criteria for donor hearts was age of <55 years, systolic blood pressure >85 mmHg at the time of final heart assessment under moderate inotropic support, heart rate of <120 bpm at the time of explantation, and left ventricular ejection fraction >40% assessed by an transcutaneous echo/Doppler study with the absence of gross wall motion abnormalities, absence of left ventricular hypertrophy, and absence of valve abnormalities. Donor hearts which were conventionally cold stored with histidine-tryptophan-ketoglutarate solution (Custodiol; Koehler Chemie, Ansbach, Germany) constituted the control group. The primary end point was the recipients' survival at 30 days and 1 and 2 years after their heart transplantation. Secondary end points were primary and chronic allograft failure, noncardiac complications, and length of hospital stay. RESULTS: Over a 2-year period (January 2006 to July 2008), 159 adult cardiac allografts were transplanted. Twenty-nine were assigned for normothermic ex vivo allograft blood perfusion and 130 for cold static storage with HTK solution. Cumulative survival rates at 30 days and 1 and 2 years were 96%, 89%, and 89%, respectively, whereas in the cold static storage group survival after oHTx was 95%, 81%, and 79%. Primary graft failure was less frequent in the recipients of an oHTx who received a donor heart which had been preserved with normothermic ex vivo allograft blood perfusion using an OCS (6.89% versus 15.3%; P = .20). Episodes of severe acute rejection (23% versus 17.2%; P = .73), as well as, cases of acute renal failure requiring haemodialysis (25.3% versus 10%; P = .05) were more frequent diagnosed among recipients of a donor heart which had been preserved using the cold static storage. The length of hospital stay did not differ (26 days versus 28 days; P = .80) in both groups. CONCLUSIONS: Normothermic ex vivo allograft blood perfusion in adult clinical orthotopic heart transplantation contributes to better outcomes after transplantation in regard to recipient survival, incidence of primary graft dysfunction, and incidence of acute rejection.

Veno-venous perfusion to cool and rewarm in thoracic and thoracoabdominal aortic aneurysm repair.

BACKGROUND: Femoro-femoral veno-arterial perfusion is an established circulatory support and cooling method for thoracic- and/or thoracoabdominal aortic aneurysm repair. However, retrograde perfusion through femoral arteries can lead to retrograde cerebral embolization and neurologic dysfunction after surgery. To avoid these complications, we have established a femoro-femoral veno-venous perfusion technique and evaluated its safety and effectiveness in elective and nonelective patients. METHODS: Common femoral veins were cannulated bilaterally percutaneously following systemic low-dose heparinization (100 IU/kg body weight). Venous blood was drained from drainage of the inferior vena cava, and venous return followed through the superior vena cava. After proximal aortic cross-clamping, veno-venous perfusion was switched to veno-arterial antegrade perfusion through the distal descending thoracic aorta to achieve spinal and visceral perfusion or through iliac arteries for distal perfusion combined with selective renovisceral blood perfusion. After completion of aortic repair, the arterial cannula was removed and the patient rewarmed just by switching back to veno-venous perfusion. Gas and temperature exchange as well as relevant hemodynamic parameters were recorded prospectively and analyzed retrospectively in 25 consecutive patients including 15 nonelective cases. RESULTS: Percutaneous insertion of outflow (28F cannula) and inflow (18F cannula) venous cannulae was complication-free and allowed unrestricted perfusion in all 25 patients. Veno-venous perfusion allowed effective cooling (mean body temperature 36.6 ± 0.6°C to 31.6 ± 2.1°C, P = .001 compared with start of cooling) and re-warming (mean body temperature 30.5 ± 3°C to 36.3 ± 0.8°C, P = .03 compared with start of re-warming). Hemodynamic as well as pulmonary parameters remained remarkably stable during surgical dissection and single lung ventilation even in nonelective cases. There was no complication associated with the perfusion technique during surgery. CONCLUSIONS: Transfemoral veno-venous cooling and re-warming results in remarkable hemodynamic stability during open repair of thoracic- and/or thoracoabdominal aortic aneurysms and eliminates the need for retrograde arterial perfusion and its inherent risks.

Further experience with distal aortic perfusion and motor-evoked potential monitoring in the management of extent I-III thoracoabdominal aortic anuerysms.

BACKGROUND: Prior studies indicated improved early mortality and paraplegia rates in a small cohort of patients with type I-III thoracoabdominal aortic aneurysms (TAAs) treated with atriofemoral bypass (AFB) and motor-evoked potentials (MEVPs) when compared with a propensity-matched cohort of patients treated with the clamp and sew (CS) method, wherein epidural cooling was the principal spinal cord protective adjunct. The use of AFB/MEVP increases the complexity of TAA repair and in this study, we address whether the early benefits will be sustained when this is applied to a general population with type I-III TAAs. METHODS: Consecutive patients undergoing repair of nonruptured Crawford extent I-III TAAs from 1/1987 to 12/2011 were identified. Patients were stratified according to operative approach (AFB/MEVP vs CS). Endpoints included long-term survival, and the composite outcome of perioperative death and paraplegia. A multivariate, risk-adjusted model was then created to determine if operative approach independently influenced outcome. RESULTS: There were 485 patients (CS = 385 [79%]; AFB/MEVP = 100 [21%]). The cohorts differed in that the AFB/MEVP group was younger (65.8 ± 12.5 years vs 70.9 ± 9.7 years; P < .001), had more extent I/II aneurysms (66% vs 50.1%; P = .005), and had more chronic dissections (30.3% vs 18.9%; P = .018). Operative variables differed in that the AFB/MEVP cohort had longer operative times (434 ± 112 minutes vs 324 ± 98 minutes; P < .001) and higher blood turnover (6028 ± 3473 mL vs 3581 ± 3111 mL; P < .0001). There was no difference in the rate of intraoperative death (AFB/MEVP = 1.0% vs CS = 0.5%; P = .50), length of intensive care unit stay (AFB/MEVP = 9.6 ± 8.6 days vs CS = 9.5 ± 12.3 days; P = .95) or hospital length of stay (AFB/MEVP = 19.9 ± 12.6 days vs CS = 21.6 ± 23.5 days; P = .49). The composite perioperative death and paraplegia rate was lower in the AFB/MEVP cohort (7% vs 19%; P = .004). The multivariate model for predictors of the composite outcome showed that AFB/MEVP was protective (odds ratio, 0.39; 95% confidence interval, 0.17-0.9; P = .028). Long-term (4-year) survival was improved in the AFB/MEVP group as well (73 ± 6% vs 60 ± 3%; P = .004). CONCLUSIONS: AFB/MEVP is an independent predictor of improved perioperative death and paraplegia rates as well as long-term survival in patients undergoing repair of type I-III TAAs and is the preferred operative strategy.

Hypothermic circulatory arrest using antegrade cerebral perfusion is safe for elective aortic arch surgery.

BACKGROUND: We hypothesized that hypothermic circulatory arrest (HCA) can be performed with a low operative risk and does not add to the morbidity in elective procedures. METHODS: A total of 178 patients with a mean (± SD) age of 62 (± 10) years underwent HCA for elective aortic surgery from April 2008 to September 2011. Pre- and postoperative clinical data were collected prospectively. RESULTS: Hemiarch replacement was performed in 97% patients. Mean logistic Euroscore I was 17% (± 15). HCA was performed at 26°C bilateral tympanic temperature. Mean HCA duration was 17 (±) min. Mean cross-clamp time was 106 (± 39) min. Overall 30-day mortality was 2% and stroke occurred in 4% of patients. Overall 6-month survival was 96%. Cox regression analysis for 6-month survival revealed four variables with significant influence: the logistic Euroscore I (p = 0.008), age (p = 0.04), cross-clamp time (p = 0.008), and reoperation for bleeding complications (p = 0.04). CONCLUSIONS: HCA with open distal anastomosis for elective aortic repair can be performed with low operative mortality, even in the elderly, and seems not to add to the morbidity of the procedure.

Quality of life following surgery of ascending aorta and aortic arch with selective antegrade cerebral perfusion.

OBJECTIVE: Surgery of the ascending aorta and aortic arch has been challenging since its inception as neurological complications may occur significantly affecting the quality of life (QOL). METHODS: From January 1998 to December 2007, 79 patients mainly suffering aortic dissection (65%) or true aortic aneurysm (34%) underwent surgery on the aortic arch employing deep hypothermic circulatory arrest and selective antegrade cerebral perfusion. QOL was assessed with the sickness-impact-profile (SIP) comprising 136 questions and 12 categories. RESULTS: All patients underwent replacement of the ascending aorta, combined with a partial (hemiarch) (n = 33; 42%) or total (n = 46, 58%) arch replacement. Thirty-day mortality was 17.7% (n = 14 patients). Perioperatively, three patients (3.8%) suffered a transitory ischemic attack (TIA) and 5.1% patients suffered a stroke. The median score of the complete questionnaire was 4.7, which demonstrates excellent QOL following such complex surgical procedures. The median physical dimension was 2.5 (0; 8), the psychosocial median score was 3.7 (1.2; 16.1), both underline an only minimal impairment of the daily life. CONCLUSION: The QOL after following the surgery of ascending aorta and aortic arch with selective antegrade cerebral perfusion is excellent on the long-term as assessed by the SIP.

Open repair of extensive thoracoabdominal and thoracic aneurysm: a preliminary single-center experience with femorofemoral distal aortic perfusion with oxygenator and without cerebrospinal fluid drainage.

Thoracoabdominal aortic aneurysms (TAAA) and extensive thoracic descending aortic aneurysms (TDA) are not accessible through standard endovascular treatment. Fenestrated and branched endograft technology was developed rapidly without widespread application. The aim of this study was to review our open repair (OR) experience of TAAA and TDA. A total of 28 patients who underwent elective OR of TAAA or TDA between January 2001 and January 2009 were analyzed retrospectively. The mean age of the patients was 65.5 years (three women). The anatomic locations of the aneurysms were as follows: six in thoracic descending aorta and 22 in thoracoabdominal aorta (14 TAAA I, two TAAA II, six TAAA III). TDA (40 patients) available for ordinary endovascular treatment and TAAA IV (35 patients) were excluded from this study. To focus on spinal cord vascularization, 25 patients were submitted for angiography. Three patients suffering from back pain required quick treatment and were excluded from angiographic investigations. Angiography procedures were contributive in 23 patients (92%). Surgical repairs were driven through left thoraco-phreno-laparotomy, with the adjunct of distal aortic perfusion (femorofemoral bypass) including the use of an oxygenator and sequential aortic cross-clamping. Cerebrospinal fluid drainage was not used in this experience. The 30-day mortality rate was 14.3% (four of 28 patients): one multiorgan failure and three pulmonary sepsis. An immediate postoperative paraplegia occurred, affecting a patient with TDA who was previously submitted for infrarenal aorta replacement, despite angiographic identification and revascularization of intercostal artery destined to spinal artery. The 1-year survival rate was 82.1% (23 of 28 patients). In the preliminary experience of this study, OR of extensive TAAA and TDA with distal aortic perfusion and an oxygenator without use of cerebrospinal fluid drainage was associated with a significant perioperative mortality rate (14.2%), a reasonable rate of paraplegia (3%), and 1-year survival rate of 82.1%.