Cardiopulmonary responses during the cooling and the extracorporeal life support rewarming phases in a porcine model of accidental deep hypothermic cardiac arrest.

BACKGROUND: This study aimed to assess cardiac and pulmonary pathophysiological responses during cooling and extracorporeal life support (ECLS) rewarming in a porcine model of deep hypothermic cardiac arrest (DHCA). In addition, we evaluated whether providing a lower flow rate of ECLS during the rewarming phase might attenuate cardiopulmonary injuries. METHODS: Twenty pigs were cannulated for ECLS, cooled until DHCA occurred and subjected to 30 min of cardiac arrest. In order to assess the physiological impact of ECLS on cardiac output we measured flow in the pulmonary artery using Doppler echocardiography as well as a modified thermodilution technique using the Swan-Ganz catheter (injection site in the right ventricle). The animals were randomized into two groups during rewarming: a group with a low blood flow rate of 1.5 L/min (LF group) and a group with a normal flow rate of 3.0 L/min (NF group). The ECLS temperature was adjusted to 5 °C above the central core. Cardiac output, hemodynamics and pulmonary function parameters were evaluated. RESULTS: During the cooling phase, cardiac output, heart rhythm and blood pressure decreased continuously. Pulmonary artery pressure tended to increase at 32 °C compared to the initial value (20.2 ± 1.7 mmHg vs. 29.1 ± 5.6 mmHg, p = 0.09). During rewarming, arterial blood pressure was higher in the NF than in the LF group at 20° and 25 °C (p = 0.003 and 0.05, respectively). After rewarming to 35 °C, cardiac output was 3.9 ± 0.5 L/min in the NF group vs. 2.7 ± 0.5 L/min in LF group (p = 0.06). At the end of rewarming under ECLS cardiac output was inversely proportional to the ECLS flow rate. Moreover, the ECLS flow rate did not significantly change pulmonary vascular resistance. DISCUSSION: Using a newly developed experimental model of DHCA treated by ECLS, we assessed the cardiac and pulmonary pathophysiological response during the cooling phase and the ECLS rewarming phase. Despite lower metabolic need during hypothermia, a low ECLS blood flow rate during rewarming did not improved cardiopulmonary injuries after rewarming. CONCLUSION: A low ECLS flow rate during the rewarming phase did not attenuate pulmonary lesions, increased blood lactate level and tended to decrease cardiac output after rewarming. A normal ECLS flow rate did not increase pulmonary vascular resistance compared to a low flow rate. This experimental model on pigs contributes a number of pathophysiological findings relevant to the rewarming strategy for patients who have undergone accidental DHCA.

Deep Hypothermic Cardiac Arrest Treated by Extracorporeal Life Support in a Porcine Model: Does the Rewarming Method Matter?

OBJECTIVES: Extracorporeal life support (ECLS) is the reference rewarming technique of accidental deep hypothermic cardiac arrest (DHCA). This study was designed to examine the impact of different rewarming blood flow rates and temperature setting of ECLS on cardiopulmonary lesions after DHCA in a porcine model of accidental hypothermia. METHODS: Twenty-four pigs were cannulated for ECLS, cooled until DHCA occurred, and subjected to 30 minutes of cardiac arrest. During the rewarming phase, we compared a low blood flow rate of 1.5 L/min versus a high flow rate of 3.0 L/min as well as two-temperature-setting rewarming strategies: a temperature during ECLS adjusted to 5°C above the central core temperature versus 38°C maintained throughout the rewarming phase. Cardiac output, hemodynamics and pulmonary function parameters were evaluated. Biologic markers of ischemia-reperfusion injuries were analyzed at baseline and at the end of the experiment. RESULTS: DHCA occurred at 21.2 ± 2°C. There was a trend for better cardiac output in groups with high blood flow (p = 0.053), with no interaction between ECLS flow and temperature (p = 0.63), a trend toward lower pulmonary vascular resistance (PVR; p = 0.075) and a significant decrease in arterial PVR in groups with high blood flow (p = 0.013) with no interaction (p = 0.47 and p = 0.60 for PVR and arterial PVR, respectively). Serum interleukin-6, tumor necrosis factor-α, receptor for advanced glycation end products (RAGE), and neuron-specific enolase were significantly increased between baseline and endpoint. The increase in the serum RAGE concentration was higher in the 38°C rewarming temperature groups compared to 5°C above adjusted temperature. There were no other significant differences in biomarkers. CONCLUSIONS: We developed a porcine model of DHCA treated by ECLS. Our data suggest that cardiac output tended to improve with a high-flow-rate rewarming strategy while a high-temperature delta between core temperature and ECLS increased the RAGE markers of lung injury.

Type A acute aortic dissection: why does the false channel remain patent after surgery?

PURPOSE: To understand why the false channel (FC) remains patent after surgery of type A acute aortic dissection (TAAAD). MATERIALS AND METHODS: Postoperative contrast-enhanced computed tomography scans of 129 patients operated for TAAAD were analyzed, and a color-Doppler ultrasound examination (CDUS) of the supra-aortic vessels (SAVs) was performed in 12 patients. RESULTS: The FC remained patent in 107 (82.9%) patients. The entry site was situated near the distal anastomosis in 43 (40.2%) patients and far from it in 44 (41.1%) patients. In 10 (9.35%) patients, an entry site was observed only in the SAVs. In 10 (9.35%) patients, no entry site was seen. Of the 12 patients explored with CDUS, a retrograde filling of the FC was observed in 11 patients. CONCLUSION: The frequent postoperative circulating aortic FC can be explained by the persistence of the primary entry tear, the presence of iatrogenic tears, and/or a retrograde filling in the SAVs.

Percutaneous drainage of postoperative pericardial effusion in cardiac surgery.

BACKGROUND AND AIM OF THE STUDY: Postoperative pericardial effusion is frequent and can be complicated by cardiac tamponade. Although the different drainage techniques are well described in the setting of medical effusion, there is not a standard postoperative effusion treatment. The aim of this work was to assess the feasibility and effectiveness of the percutaneous pericardial drainage. METHODS: This a retrospective study involving 197 patients from 1990 to 2008. Drainage was performed by subxiphoid puncture (91.9%) or left parasternal puncture (8.1%) between 3 and 690 days following a cardiac procedure via median sternotomy. Effusion thickness was at least 10 mm in the subcostal echocardiography view. RESULTS: No deaths directly related to the procedure were observed. Complete and enduring drainage was achieved in 158 patients (80.2%). The procedure failed for 22 patients (11.2%) because no fluid was drained in 14 cases (7.1%) and a right ventricular puncture in 8 cases (4.1%). Recurrence of the effusion, which occurred for 17 patients (8.6%), was more frequent if an effusion of more than 5 mm persisted after the first drainage (P = 0.024) and if the drainage was performed outside the operating room because of emergency (P = 0.046). Risk factors for mortality were recurrence of the effusion (P = 0.04) and drainage performed outside the operating room (P = 0.007). CONCLUSIONS: Percutaneous pericardial drainage is effective to treat postoperative pericardial effusion. When the effusion is thicker than 10 mm and accessible, it can be the initial strategy and surgical drainage can serve as an alternate strategy in case of failure and complications of this procedure.

Hemorrhagic tamponade due to cardiac angiosarcoma.

Prognosis of angiosarcoma, the most common primary malignant cardiac tumor, is very poor. An early detection and treatment may extend survival beyond one year. Newer imaging modalities, including magnetic resonance imaging (MRI), play an important role in the evaluation of cardiac masses. The case of a man admitted to the emergency room for a cardiac tamponade is reported. Thoracic computed tomography and MRI diagnosed a pericardial tumor, for which surgical biopsy revealed an angiosarcoma. Chemotherapy was started, and the patient survived for 28 months. Etiologies of hemorrhagic tamponades are discussed, as well as treatment of cardiac angiosarcoma.

[Percutaneous extracorporeal life support in acute severe hemodynamic collapses: single centre experience in 100 consecutive patients]. / Assistance circulatoire extracorporelle percutanée dans les défaillances hémodynamiques aiguës graves: expérience monocentrique chez 100 patients consécutifs.

BACKGROUND: Extracorporeal life support (ECLS) is a circulatory assistance device that is increasingly used in adults undergoing cardiopulmonary arrest (CPA) or hemodynamic collapse when conventional therapies fail. OBJECTIVES: To assess the feasibility and outcomes of 100 consecutive arteriovenous percutaneous ECLS procedures at the Grenoble University Hospital between January 2002 and September 2007. METHODS: Monocentric descriptive registry with one-year prospective follow-up. RESULTS: An ECLS device was successfully used in 93% of patients. Its indication was cardiogenic shock in 50% of the cases, CPA in 38% of the cases and unsuccessful weaning of cardiopulmonary bypass (CPB) after cardiothoracic surgery in 12% of the cases. Direct complications of ECLS were observed in 56% of patients, the most frequent being hemorrhage at the intravenous puncture site requiring red blood cell transfusions (26%), and lower limb ischemia (19%). Weaning from ECLS was achieved in 33 patients (44% cardiogenic shocks, 13% CPAs, 50% CPB weaning failures) and 20 patients were discharged from the hospital (26% cardiogenic shocks, 10.5% CPAs and 25% CPB weaning failures). All are still living without any serious sequelae (mean follow-up period of 16.8 months). CONCLUSION: The use of ECLS in CPA patients, especially with cardiogenic shock, is feasible with satisfactory survival rates, given the extreme severity of their initial state.

Endovascular stent-graft management of aortic intramural hematomas.

PURPOSE: To report initial experience with endovascular stent-grafting in aortic intramural hematoma (IMH). MATERIALS AND METHODS: From 2000 to 2006, 15 patients (mean age, 67 years; range, 54-83 y) underwent endovascular treatment of aortic IMH. Thirteen patients were admitted for acute aortic syndrome and two for traumatic aortic injury. An endovascular procedure was performed as primary treatment for four patients (type A IMH, n = 3; type B IMH, n = 1) and as a second-line therapy in 11 patients because of unfavorable evolution (type A IMH, n = 1; type B IMH, n = 10). All stent-grafts were placed in the descending aorta, even for type A IMH. The mean follow-up was 21 months (range, 6-72 months). RESULTS: The primary success rate was 93%, with complete exclusion of the lesion (n = 14). Exclusion was partial for one patient with a type I endoleak (7%). The 30-day mortality rate was zero. IMH evolution was favorable in all cases, with decreased aortic wall thickening (n = 8) or complete regression (n = 7). Complications associated with endovascular repair were mainly related to aneurysm formation (20%). The late death rate was 7%. CONCLUSIONS: Endovascular stent-graft treatment can be performed in the management of complicated IMH, even in some cases of type A IMH, when an intimal lesion is located in the isthmus or descending aorta with contraindications to surgery. This procedure offers low morbidity and mortality rates, representing a feasible therapeutic option especially for elderly patients with comorbidities. Further studies are necessary to confirm these preliminary results.

[Isolated coronary surgery in the octogenarian. Immediate results and analysis of long-term survival rate and quality of life]. / Chirurgie coronaire isolée chez l'octogenaire: Résultats immédiats et analyse du taux de survie et de la qualité de vie à long terme.

BACKGROUND: There are almost three million octogenarians living in France, many of whom present with a coronaropathy. Moreover, it appears that life expectancy at 80 years of age is still important. OBJECTIVE: To evaluate the results of coronary surgery among these patients. METHODS: Eighty-eight consecutive octogenarians who had an isolated coronary artery bypass surgery between 1996 and 2002 were compared with 165 patients 60 to 70 years of age; the two groups had been paired according to the main risk factors. Patients were contacted by telephone and then received a quality-of-life-related questionnaire. RESULTS: Operative mortality was 2.3% in the octogenarian versus 1.2% in the 60- to 70-year-old group (P not significant). There was more low cardiac output syndrome, postoperative acute renal failure and transfusion in octogenarians. Long-term survival (average duration of follow-up was 3.8 years) was higher in the 60- to 70-year-old group: 89.7% versus 77.9% (P=0.025). Four independent risk factors of long-term increased mortality were found: age, diabetes, history of stroke and postoperative blood transfusion. Finally, the long-term survival in the octogenarians who had this surgery was higher than in the octogenarians of the general French population to a significant degree, with a quality of life considered to be satisfactory. CONCLUSION: For selected octogenarians, an isolated coronary surgery can be proposed, with short- and long-term results comparable with those of a younger population.

Giant aneurysm of the proximal segment of the left anterior descending artery in a patient with Behçet's disease--a combined approach.

Behçet's disease is an autoimmune, multisystem disease presenting with recurrent oral and genital ulceration as well as ocular involvement. Aneurysmal degeneration of coronary arteries remains a rare phenomenon in Behçet's disease. The case of a patient with Behçet's disease who presented with severe stenosis of the left anterior descending artery associated with a giant aneurysm of the proximal segment is described. Surgical revascularization was proposed, followed by percutaneous embolization of the aneurysm.

Preoperative predictive factors for mortality in acute type A aortic dissection: an institutional report on 217 consecutives cases.

Surgical treatment of type A acute aortic dissection remains a challenge, especially in elderly patients or in patients with a critical preoperative status. We have retrospectively assessed our series over a 15-year period starting in 1990, including patients operated under cardiac massage for preoperative cardiac arrest occurring in the operating room. There were 217 patients (mean age, 61.5+/-13.5 years; 16 patients >80 years). Preoperative shock was noted in 21.7%, including 14 patients operated under cardiac massage. Operating procedures were: modified Bentall (31%), aortic tube (67.1%), other (1.9%), aortic arch procedure in 26.4%. Overall mortality rate was 19.8% with an exponential increase with age (50% over 80 years). Of 14 patients operated under cardiac massage, three have been discharged: one ventricular fibrillation due to an acute myocardial infarction and two among the 13 with acute aortic ruptures in cardiac arrest (one being a redo, the adhesions limiting the tamponade). Our results confirmed age and preoperative shock prior to surgery as risk factors, and the fact that operating on a patient under cardiac massage for cardiac arrest due to an aortic rupture is probably not a reasonable therapeutic choice.

Emergency endovascular stent graft repair for acute blunt thoracic aortic injury: a retrospective case control study.

OBJECTIVE: To compare surgical and endovascular stent graft (ESG) treatment of blunt thoracic aortic injury (BAI) in the emergency setting. DESIGN AND SETTING: Retrospective case control study in two surgical intensive care units of a university hospital. PATIENTS: 30 patients who presented with BAI between 1995 and 2005: 17 treated surgically and 13 by ESG. The two groups were comparable for the severity of trauma and mean delay before treatment; the mean age was higher in the ESG group (46+/-18 vs. 35+/-15 years). RESULTS: In the surgical group time spent in the operating theater was longer (310+/-130 vs. 140+/-48 min) and blood losses higher (2000+/-1300 vs. no significant bleeding); aortic clamping time was 48+/-20 min. The mortality rate was 15% with ESG (n=2) and 23% with surgery (n=4). Complications of the procedure were more frequent in the surgical group (1 vs. 7). In the ESG group there was one pulmonary embolism. In the surgical group there were three neurological complications, one acute aortic dissection, one perioperative rupture, one periprosthetic leak, and one septic shock. Two complications (postoperative aortic dissection and paraplegia) appeared in the same patient in the surgical group. Intensive care unit length of stay, duration of mechanical ventilation, and catecholamine support were similar in the two groups. CONCLUSIONS: Stent graft for emergency treatment of BAI is efficient and is associated with fewer complications than surgical treatment.