Impact of Left Heart Bypass on Arterial Oxygenation During One-Lung Ventilation for Thoracic Aortic Surgery.

OBJECTIVE: The aim of this study was to reveal the mechanism of improved arterial oxygenation by measuring the changes in oxygenation before and after initiation of left heart bypass (LHB) during one-lung ventilation (OLV) for thoracic aortic surgery. DESIGN: Prospective, observational study. SETTING: Single-institution, private hospital. PARTICIPANTS: The study comprised 50 patients who underwent aortic surgery via a left thoracotomy approach with LHB circulatory support. INTERVENTIONS: Patients were ventilated using pure oxygen during OLV, and the ventilator setting was left unchanged during the measurement period. MEASUREMENTS AND MAIN RESULTS: The measurement of partial pressure of arterial oxygen (PaO2) was made at the following 4 time points: 2 minutes after heparin infusion (point 1 [P1]), 2 minutes after inflow cannula insertion through the left pulmonary vein (P2), immediately before LHB initiation (P3), and 10 minutes after LHB initiation (P4). The mean±standard deviation (mmHg) of PaO2 measurements at the P1, P2, P3, and P4 time points were 244±121, 250±123, 419±122, and 430±109, respectively, with significant increases between P1 and P3, P1 and P4, P2 and P3, and P2 and P4 (p<0.0001, respectively). No significant increase in PaO2 was seen between P1 and P2 or between P3 and P4. CONCLUSIONS: The improved arterial oxygenation during OLV in patients who underwent thoracic aortic surgery using LHB can be attributed to the insertion of an inflow cannula via the left pulmonary vein into the left atrium before LHB.

Left heart bypass for thoracoabdominal aortic aneurysm repair: technical aspects.

There are different surgical techniques for providing circulatory support during the repair of thoracoabdominal aortic aneurysms. They all aim at reducing the afterload of the heart and the preservation of distal organ perfusion. Partial or total extracorporeal circulation with or without cooling and left heart bypass (LHB) are actually the most used surgical approaches. The objective of this study was to describe and comment on the technical aspects of the LHB. We briefly describe our results and put them into perspective based on the current literature.

Indicadores pronósticos clínicos en el posoperatorio de cirugía cardiovascular pediátrica y su relación con la cinética del estrés oxidativo / Prognostic indicators after cardiac surgery in children and their relationship with the oxidative stress response

Objetivos. Analizar la evolución de parámetros de estrés oxidativo en el posoperatorio de cirugía cardiovascular pediátrica y correlacionarlos con diferentes indicadores clínicos pronósticos. Material y métodos. Treinta niños, de entre un mes y 14 años, peso > 5 kg, sometidos a circulación extracorpórea. Se obtuvieron muestras preoperatoria, posoperatoria inmediata y tras 18-20 h. Se analizó la capacidad de peroxidación lipídica de las membranas celulares mediante la cuantificación de productos de reacción con el ácido tiobarbitúrico, cuyo principal representante es el malondialdehído; se cuantificó el contenido celular de glutatión total, oxidado y reducido (representantes de la respuesta antioxidante). Se analizaron las variables clínicas que permitieran establecer una puntuación para el síndrome de respuesta inflamatoria sistémica asociado a circulación extracorpórea. Resultados. Treinta pacientes con una mediana de edad de 4,1 años (rango intercuartílico [RIC]: 2,7; 8,0); el 62,1% eran niñas; mediana de desviaciones estándar de peso −0,39 (RIC: −0,76; 0,24), de talla −0,22 (RIC: −0,74; 0,27) y de IMC −0,43 (RIC: −1; 0,45). Mediana de tiempo quirúrgico 79 min (RIC: 52,5; 125,5), mediana de pinzamiento 38,5 min (RIC: 22; 59). Aumentó el malondialdehído y disminuyó el glutatión en ambos momentos posoperatorios, con clara correlación directa, estadísticamente significativa, del tiempo de circulación extracorpórea con el porcentaje de descenso de glutatión total entre preoperatorio y posoperatorio inmediato y entre el preoperatorio y el posoperatorio tardío. Hubo una correlación estadística entre los niveles de glutatión total tras 18-20 h posoperatorias y el tiempo de duración de la ventilación mecánica y la pertenencia al grupo de síndrome de respuesta inflamatoria sistémica. Conclusiones. La circulación extracorpórea activa mediadores inflamatorios, máximo tras el pinzamiento aórtico, mejorando tras 24 h, siendo dependiente de los tiempos quirúrgicos. El desarrollo de respuesta inflamatoria está asociado a una mayor duración de la ventilación mecánica, una estancia más prolongada en Cuidados Intensivos, puntuaciones mayores del Modelo de Aristóteles y tiempos más largos quirúrgicos. Los que no cumplen criterios de respuesta inflamatoria tienen más niveles de glutatión en el posoperatorio tardío (AU)

Objectives. To analyse the trend in lipid peroxidation and antioxidant response as key markers of oxidative stress after paediatric cardiovascular surgery, and compare them with other internationally accepted clinical prognostic indicators. Patients and methods. A prospective study was conducted on 30 children aged one month to 14 years, weight > 5 kg, undergoing cardiopulmonary bypass surgery. Blood samples were taken just before the intervention, immediately after surgery, and after 18-20 h. Cell membrane lipid peroxidation was analysed by quantifying malondialdehyde, as well as measuring total glutathione (oxidized and reduced), as representatives of antioxidant response. An analysis was also performed on clinical variables for establishing a score for the systemic inflammatory response syndrome associated with cardiopulmonary bypass. Results. The study included 30 children with a mean age of 4.1 years old (interquartile range [IQR]: 2.7; 8.0). Of these, 62.1% were girls. The standard deviation of the median weight was −0.39 (IQR: −0.76; 0.24), the median height was −0.22 (IQR: −0.74; 0.27), and the median BMI was −0.43 (IQR: −1; 0.45). The final surgery times were divided into 2 parts: total time of extracorporeal circulation, with a mean of 79 min (IQR: 52.5; 125.5), and the clamping time, a measurement included in the previous figure with a mean value of 38.5 min (IQR: 22; 59). Malondialdehyde increased and glutathione decreased in postoperative time, with clear, statistically significant direct correlation between time of extracorporeal circulation and percentage decrease in total glutathione between preoperative and immediate postoperative time, and a decline between the preoperative and late postoperative. There was a statistical correlation between total glutathione levels at 18-20 h postoperatively and the duration of mechanical ventilation and inflammatory systemic response syndrome. Conclusions. Surgery with extracorporeal circulation performed in children activates inflammatory mediators, being maximum after aortic clamping, and improving after the first 24 h. The level of oxidative stress activation depends on surgical times. The development of systemic inflammatory response syndrome is associated with longer duration of mechanical ventilation, longer stay in intensive care, higher scores in the Aristotle model and longer surgical times. Those who do not meet criteria for inflammatory response have higher levels of glutathione in first 24 h (AU)

Takayasu's or tuberculous arteritis?

Takayasu's arteritis (TA) is a large vessel vasculitis of unknown aetiology characterised by involvement of the aorta and its major branches. Tuberculous arteritis of the aorta is an uncommon condition usually secondary to the dissemination of Mycobacterium tuberculosis infection from the mediastinum and/or lung to the adjacent aorta; this may mimic TA. We report a case of a 23-year-old woman with cutaneous granulomatous vasculitis and saccular aneurysmal dilation of the aorta and large vessels, and highlight the findings shared by TA and tuberculous arteritis.

Implante de un stent en la anastomosis del colector a la aurícula izquierda tras cirugía correctora de drenaje venoso pulmonar anómalo total / Stent Implantation in the Anastomosis After Correction of a Total Anomalous Pulmonary Venous Connection

No disponible

Surgical repair of coarctation of aorta in adults under left heart bypass.

OBJECTIVE: To describe our experience with repair of coarctation of the aorta in adults using left heart bypass. METHODS: From November 2007 to October 2009, eight adult patients with coarctation of the aorta underwent surgical repair under circulatory support using a left atrium to femoral artery bypass circuit, with graft interposition tube through left posterolateral thoracotomy. Five patients were female, with mean age of 31.5 ± 13.1 years. All patients had hypertension and others associated cardiovascular diseases. RESULTS: There were no deaths or neurological complications. The mean surgical time was 308 minutes with mean left heart bypass and distal aortic clamping time of 73 and 65 minutes respectively. Postoperative bleeding was 696 ml in average. Six patients developed severe hypertension postoperatively requiring intravenous vasodilators. The mean length of stay was 9 days. A significant reduction of gradient blood pressure occurred. Echocardiographic follow-up up to two months postoperatively showed mean aortic / graft gradient of 20.3 mmHg. CONCLUSION: In this series the use of left heart bypass showed to be a safe option in the surgical correction of coarctation of the aorta in adults, especially in patients with abnormal aortic wall. There was no spinal cord ischemia in the cases studied.

Correção cirúrgica da coarctação da aorta em adultos sob assistência circulatória extracorpórea esquerda / Surgical repair of coarctation of aorta in adults under left heart bypass

OBJETIVO: Descrever a experiência do serviço com a correção da coarctação da aorta em adultos utilizando assistência circulatória esquerda. MÉTODOS: De novembro de 2007 a outubro de 2009, oito pacientes adultos com coarctação da aorta foram submetidos a correção cirúrgica com interposição de enxerto tubular através de toracotomia póstero-lateral esquerda e uso de assistência circulatória com uso de circuito átrio esquerdo e artéria femoral. Cinco pacientes eram do sexo feminino e tinham idade média de 31,5 ± 13,1 anos. Todos tinham hipertensão arterial sistêmica (HAS) e apresentavam doenças cardiovasculares associadas. RESULTADOS: Não houve óbitos ou complicações neurológicas. O tempo médio cirúrgico foi de 308 minutos, o tempo médio de assistência circulatória de 73 minutos e o de pinçamento aórtico médio de 65 minutos. O sangramento médio no pós-operatório foi de 696 ml. Seis pacientes evoluíram com HAS grave no pós-operatório, sendo necessário uso de vasodilatadores endovenosos. As altas hospitalares ocorreram em média no 9º dia pós-operatório. Houve redução significativa do gradiente médio da pressão arterial sistêmica. O seguimento ambulatorial com ecocardiograma até dois meses de pós-operatório demonstrou gradiente aorta/enxerto médio de 20,3 mmHg. CONCLUSÃO: O uso da assistência circulatória esquerda pode ser uma opção na correção cirúrgica da coarctação da aorta em adultos, principalmente em pacientes com alterações parede da aorta, não sendo observada isquemia medular nos casos estudados.

OBJECTIVE: To describe our experience with repair of coarctation of the aorta in adults using left heart bypass. METHODS: From November 2007 to October 2009, eight adult patients with coarctation of the aorta underwent surgical repair under circulatory support using a left atrium to femoral artery bypass circuit, with graft interposition tube through left posterolateral thoracotomy. Five patients were female, with mean age of 31.5 ± 13.1 years. All patients had hypertension and others associated cardiovascular diseases. RESULTS: There were no deaths or neurological complications. The mean surgical time was 308 minutes with mean left heart bypass and distal aortic clamping time of 73 and 65 minutes respectively. Postoperative bleeding was 696 ml in average. Six patients developed severe hypertension postoperatively requiring intravenous vasodilators. The mean length of stay was 9 days. A significant reduction of gradient blood pressure occurred. Echocardiographic follow-up up to two months postoperatively showed mean aortic / graft gradient of 20.3 mmHg. CONCLUSION: In this series the use of left heart bypass showed to be a safe option in the surgical correction of coarctation of the aorta in adults, especially in patients with abnormal aortic wall. There was no spinal cord ischemia in the cases studied.

Temporary mechanical circulatory support for Takotsubo cardiomyopathy secondary to primary mediastinal B-cell lymphoma.

BACKGROUND: Left heart mechanical circulatory support (MCS) through the left chest via the pulmonary vein and descending thoracic aorta is a good option for patients with an inaccessible anterior mediastinum and/or poor peripheral access. MATERIALS AND METHODS: We report the case of a 19-year-old small female with a newly discovered bulky primary mediastinal diffuse large B-cell lymphoma (PMBL) who developed refractory inverted Takotsubo cardiomyopathy (TC) with cardiogenic shock. RESULTS: Temporary MCS was implemented in order to stabilize the patient and proceed with a chemotherapy treatment. Given the patient's oncologic "frozen" mediastinum and the presence of poor peripheral arterial access, the left heart temporary MCS was successfully implanted through a left mini-thoracotomy via the left inferior pulmonary vein and descending thoracic aorta. CONCLUSIONS: This is the first report of temporary MCS to treat inverted TC and diffuse PMBL.

The effect of left heart bypass on pulmonary blood flow and arterial oxygenation during one-lung ventilation in patients undergoing descending thoracic aortic surgery.

STUDY OBJECTIVE: To study the effect of left heart bypass (LHB) on regional pulmonary blood flow and arterial oxygenation during one-lung ventilation (OLV). DESIGN: Prospective, observational study SETTING: Operating room PATIENTS: 14 ASA physical status II and III patients scheduled to undergo descending thoracic or thoracoabdominal aortic surgery using LHB. INTERVENTIONS AND MEASUREMENTS: Parameters studied during OLV with 100% oxygen before and during LHB mean arterial pressure, heart rate, pulmonary artery pressure, pulmonary capillary wedge pressure, central venous pressure, cardiac index, cardiac output, arterial oxygen tension (PaO(2)), mixed venous oxygen pressure, alveolar arterial oxygen difference (P((A-a)O2)), and right upper pulmonary venous flow (RUPVF). Right upper pulmonary venous flow was measured using transesophageal echocardiography. MAIN RESULTS: With the transition to OLV, there was a significant decrease in PaO(2) and a significant increase in P((A-a)O2). However once LHB was initiated, these values improved significantly (P = 0.0007 and 0.0004, respectively) with the simultaneous increase in RUPVF (P = 0.0018). CONCLUSIONS: LHB improved pulmonary blood flow to the dependent lung and arterial oxygenation during OLV in descending thoracic aortic surgery.

Use of a multi-modality life support system.

The purpose of this study was to describe the design and utilization of a multi-modality life support system (MMLSS), which is used to provide extracorporeal support for cases such as left heart bypass (LHB), extracorporeal life support (ECLS), veno-venous bypass, and hypothermic resuscitation. The design of the MMLSS consisted of a mobile cart outfitted with a centrifugal pump, heater cooler, an in-line blood gas monitor, oxygen blender/flow meter, and assorted safety devices (pressure sensors and level and bubble detectors). A single disposable circuit was used for all procedures and designed to be easily modifiable to support a variety of clinical scenarios, with and without the use of an oxygenator. The system was designed for rapid deployment throughout the hospital. From January 1, 2006 to December 31, 2007, the MMLSS has been used in three LHB procedures (63 +/- 72 minutes), four adult ECLS cases (57.2 +/- 56.9 hours), four veno-venous bypasses (72 +/- 35 minutes), and one hypothermic resuscitation (182 minutes). The MMLSS was designed to be used in patients > 20 kg and could achieve flows in the range of 1-5.5 L. There were no complications associated with the device. The MMLSS is a versatile system that can be used throughout the hospital with a single disposable circuit, accommodating a diverse caseload in a safe and reproducible manner.

Surgical repair of thoracoabdominal aortic aneurysms.

Morbidity and mortality following thoracoabdominal aortic aneurysm (TAAA) repair are tremendous. Preoperative assessment is essential in detecting cardiac and pulmonary risk factors in order to reduce cardiopulmonary complications. Paraplegia and renal failure are main determinants of postoperative mortality and therefore gained substantial attention during the last decades. Left heart bypass, cerebrospinal fluid (CSF) drainage and epidural cooling have significantly reduced paraplegia rate, however, this dreadful event still occurs in up to 25% of patients undergoing type II repair. Renal failure has been partly prevented by means of retrograde aortic perfusion and cooling but renal failure still remains a significant problem. We have evaluated the effects of protective measures aiming for reduction of paraplegia and renal failure. Monitoring motor evoked potentials (MEPs) is an accurate technique to assess spinal cord integrity during TAAA repair, guiding surgical strategies to prevent paraplegia. Selective volume- and pressure controlled perfusion is a technique to continuously perfuse the kidneys during aortic cross clamping and subsequent circulatory exclusion In patients with atherosclerotic thoracoabdominal aortic aneurysms, blood supply to the spinal cord depends on a highly variable collateral system. In our experience, monitoring MEPs allowed detection of cord ischemia, guiding aggressive surgical strategies to restore spinal cord blood supply and reduce neurologic deficit: overall paraplegia rate was less than 3%. We believe that these protective measures should be included in the surgical protocol of TAAA repair, especially in type II cases. Renal and visceral ischemia can be reduced significantly by continuous perfusion during aortic cross clamping in TAAA repair. Not only sufficient volume flow but also adequate arterial pressure appears to be essential in maintaining renal function.Obviously, endovascular modalities have been successfully applied in TAAA patients, the majority of which as part of hybrid procedures. Technological innovation will eventually cause a shift from open to minimal invasive surgical repair. At present, however, open surgery is considered the gold standard for TAAA repair, especially in (relatively) young patients and patients suffering from Marfan's disease.

Stent grafting technique using Matsui-Kitamura (MK) stent for patients with aortic arch aneurysm.

OBJECTIVE: Although several methods of stent-grafting for patients with aortic arch aneurysm have been reported, these methods have been associated with several complications such as endoleak and migration. We developed a new method using Matsui-Kitamura (MK) stent-graft following extra-anatomic arch vessels bypass by selective cerebral perfusion (SCP) under left heart bypass (LHB). METHODS: Between December 2001 and December 2003, 12 patients with aortic arch aneurysm were treated according to this new method. All patients were male with an average age of 71.3+/-6.4 years. There were 5 patients with severe pulmonary dysfunction, 4 with renal dysfunction, one with severe cardiac dysfunction and 3 with preoperative cerebral infarction. Under SCP using LHB, the extra-anatomic arch vessel bypass was established. The MK stent-graft was delivered into the aortic arch. Coronary artery bypass grafting (CABG) was concomitantly performed in one patient. RESULTS: There were no cases of endoleak, migration or hospital death. One patient, who had a past history of cerebrovascular disease, suffered a minor stroke, and one patient, who was performed CABG to the mid-left anterior descending branch (LAD) using the left internal thoracic artery (LITA), presented paraparesis. Although two patients of chronic renal failure underwent scheduled CHDF on account of using the contrast medium during the procedure, all of them were weaned from hemodialysis. However, there were no other postoperative complications such as, respiratory failure or cardiac dysfunction. CONCLUSIONS: Endovascular stent grafting EVSG using the MK stent with extra-anatomic arch vessel bypass under SCP using LHB could be a useful and less invasive method for patients with aortic arch aneurysm who are at a high surgical risk.

Effects of acute left ventricular unloading on right ventricular function in normal and chronic right ventricular pressure-overloaded lambs.

OBJECTIVE: Right ventricular pressure overload occurs in several types of (congenital) heart disease, as well as in pulmonary disease. Clinical outcome in some of these patient groups might in part be related to left ventricular loading conditions. The effects of left ventricular unloading on the function of the hypertrophic right ventricle have not been studied. We aimed to study the effects of left ventricular unloading on right ventricular hemodynamics and contractility in an animal model of chronic right ventricular pressure overload. METHODS: In lambs the pulmonary artery was chronically banded to increase right ventricular pressure to systemic levels. After 8 weeks, right ventricular contractility and hemodynamic function were assessed in these lambs, as well as in age-matched control animals, by using a combined pressure-conductance catheter in the right ventricle during baseline conditions and during complete bypass of the left ventricle. RESULTS: In both groups acute left ventricular unloading significantly decreased left ventricular pressure to low levels while aortic pressure was maintained. In the right ventricle of the control group, both end-systolic and end-diastolic volumes increased with left ventricular unloading (P <.01) while end-systolic pressure was maintained. Cardiac output was unchanged despite decreased right ventricular contractility. In the banding group acute left ventricular unloading also decreased right ventricular contractility but increased cardiac output. During acute left ventricular unloading, diastolic stiffness was unchanged in the control group, whereas it was significantly decreased in the banding group. CONCLUSIONS: Both in normal hearts and in hearts subject to chronic right ventricular pressure overload, acute left ventricular unloading decreases right ventricular contractility. Although no effects on cardiac output are encountered in normal hearts during left ventricular bypass, cardiac output is improved in right ventricular pressure-overloaded hearts, most likely related to improved right ventricular diastolic compliance.

The use of left heart bypass in the repair of thoracoabdominal aortic aneurysms: current techniques and results.

The surgical repair of thoracoabdominal aortic aneurysms (TAAA) remains challenging. The prevention of spinal cord ischemic complications requires a multidisciplinary approach. The protective effect of left heart bypass (LHB), particularly regarding spinal cord ischemia, during the repair of extensive TAAA is evaluated here. Data from 1,250 consecutive patients who underwent the repair of extent I or extent II TAAA over a 16-year period was prospectively entered into a database. LHB was used in 666 (53.3%) patients. This group was retrospectively compared with 584 (46.7%) patients who had undergone surgery without the use of LHB. A total of 1,173 (93.8%) patients were 30-day survivors. Paraplegia or paraparesis developed postoperatively in 68 (5.5%) patients. In patients with extent I TAAA, paraplegia and paraparesis rates in the LHB cohort (9 of 290, 3.1%) and those without LHB (13 of 313, 4.2%) were statistically similar (P=0.866). The latter was observed despite the fact that longer clamp times were used in the LHB group. In patients with extent II TAAA, the LHB group had a statistically significant lower incidence of paraplegia or paraparesis (17 of 375, 4.5%) compared with the non-LHB group (29 of 259, 11.2%; P=0.019). In our experience, we identified LHB as protective for reducing the risk of postoperative paraplegia and paraparesis in patients who underwent the repair of extent I and extent II TAAA, the latter statistically significant.

Transesophageal echocardiography in the management of left atrio-femoral bypass during thoracoabdominal aortic aneurysm repair: a case report.

PURPOSE: To describe the utility of transesophageal echocardiography (TEE) in a patient undergoing thoracoabdominal aneurysm (TAA) surgery using left atrio-femoral bypass (LAFB). CLINICAL FEATURES: A 57-yr-old female patient underwent repair of type II TAA. As per institutional routine, LAFB technique was used. Initial difficulty with the pump flow was encountered. TEE images showed that the left atrial cannula was positioned against the left atrial wall. The cannula position was adjusted and the pump flow was established. During different stages of the surgery, TEE was used to monitor the left ventricular cavity size and its function. This allowed the adjustment of LAFB pump flow relative to left ventricular filling and optimal fluid resuscitation in order to maintain both upper and lower body perfusion. CONCLUSION: In this patient, TEE was useful to confirm the correct position of the left atrial cannula and for hemodynamic management during LAFB.

[Early postoperative period in children with hypoplastic left heart syndrome in the comparison of classic and modified Norwood procedures]. / Wczesny okres pooperacyjny u dzieci z zespolem niedorozwoju lewego serca--porównanie klasycznej i zmodyfikowanej operacji Norwooda.

INTRODUCTION: The Norwood operation in neonates with hypoplastic left heart syndrome is associated with very high mortality. AIM: To compare early postoperative period in children who underwent classic operation to that in patients who underwent a new modification of the Norwood procedure. METHODS: Evaluation of the early postoperative period (72 h after the operation) in patients who underwent classic operation: Group 1 (31 children) and patients in whom modified Norwood procedure was performed: Group 2 (18 children). The surgical technique of the modified Norwood procedure was presented (right ventricle- to = pulmonary artery shunt and neo-aorta reconstruction by direct anastomosis between aortic arch and main pulmonary artery). RESULTS: In Group 1 in 15 (48.4%) children circulatory collapse occurred, requiring resuscitation, which was unsuccessful in 9 (60%) cases. In Group 2 one child died and early postoperative period of the other was uneventful. The mean circulatory arrest time in deep hypothermia was significantly (p = 0.002) shorter in Group 2 (mean: 33.7 +/- 8.7 min, range 25-53 min) than in Group 2 (mean: 54.1 +/- 6.6 min, range 41-76 min) and cardiopulmonary bypass time was not significantly prolonged (Group 1: mean 70.5 +/- 24.2 min, range 48-167 min; Group 2: mean 62.5 +/- 9.6 min, 39-84 min) (p = 0.765). In Group 2 there was significantly higher diastolic pressure 4, 8, 12, 24 and 36 h after the operation (p < 0.001, p = 0.005, p = 0.037, p = 0.017, p = 0.022, respectively). CONCLUSION: The new modification of the Norwood procedure ensures stable conditions in early postoperative period. We believe that short circulatory arrest time without prolongation of cardiopulmonary bypass time and higher diastolic pressure (the location of the proximal shunt end beneath the valve of the systemic circulation) improves the function of the heart.

Renal perfusion during thoracoabdominal aortic operations: cold crystalloid is superior to normothermic blood.

BACKGROUND: Renal failure remains a common complication of thoracoabdominal aortic aneurysm repair. The purpose of this randomized clinical trial was to compare two methods of selective renal perfusion--cold crystalloid perfusion versus normothermic blood perfusion--and determine which technique provides the best kidney protection during thoracoabdominal aortic aneurysm repair. METHODS: Thirty randomized patients undergoing Crawford extent II thoracoabdominal aortic aneurysm repair with left heart bypass had renal artery perfusion with either 4 degrees C Ringer's lactate solution (14 patients) or normothermic blood from the bypass circuit (16 patients). Acute renal dysfunction was defined as an elevation in serum creatinine level exceeding 50% of baseline within 10 postoperative days. RESULTS: One death occurred in each group. One patient in the blood perfusion group experienced renal failure requiring hemodialysis. Ten patients (63%) in the blood perfusion group and 3 patients (21%) in the cold crystalloid perfusion group experienced acute renal dysfunction (p = 0.03). Multivariable analysis confirmed that the use of cold crystalloid perfusion was independently protective against acute renal dysfunction (p = 0.02; odds ratio, 0.133). CONCLUSIONS: When using left heart bypass during repair of extensive thoracoabdominal aortic aneurysms, selective cold crystalloid perfusion offers superior renal protection when compared with conventional normothermic blood perfusion.

Traumatic rupture of the thoracic aorta: cohort study and systematic review.

PURPOSE: Through a systematic review of the literature, we identified the optimal management of traumatic ruptures of the thoracic aorta (TRTA) and reported the results of a cohort of patients treated with the clamp-and-sew technique (CAS) at a tertiary trauma center. METHODS: Studies were identified through Medline and the Cochrane library and from reference lists and papers from the authors' files. Studies with a single consistent protocol (CAS, Gott shunt [GS], left heart bypass [LHB], or partial cardiopulmonary bypass [PCPB]) that reported mortality and neurologic outcomes were included. Relevance, validity, and data extraction were performed in duplicate. A retrospective review of charts from June 1992 to August 2000 provided the database for our experience. RESULTS: Twenty studies reporting on 618 patients were found to be relevant. Interobserver agreement for relevance and validity decisions was high. Mortality rates for repair with CAS, GS, LHB, and PCPB were 15%, 8%, 17%, and 10%, respectively, and for paraplegia they were 7%, 4%, 0%, and 2%, respectively. The difference in mortality rates was not statistically significant. CAS had a higher incidence of neurologic deficits than GS (odds ratio [OR], 1.8; 95% CI, 0.4-8), LHB (OR, 6.4; 95% CI, 0.8-50), and PCPB (OR, 3.4; 95% CI, 1-10). In our cohort of 25 patients, 21 underwent surgery with CAS. The median abbreviated injury severity score was 20 (range, 4-50). The mean aortic clamp time was 30 +/- 12 minutes. Aortic repair was achieved with graft interposition in 43% of patients, and simple suture was achieved in 57% of patients. Mortality (10%) and neurologic complication (paraplegia, 11%; paraparesis, 5%) rates were not statistically different from those reported in the literature. CONCLUSION: CAS is associated with a similar mortality rate but a higher incidence of neurologic deficits than methods with distal aortic perfusion.