Selective Organ Perfusion Research Articles

光ファイバ圧力センサを搭載した細径臓器灌流カテーテル

A small diameter (O.D. 1.47 mm) selective organ perfusion catheter with fiber-optic pressure sensor for monitoring perfusion pressure has been fabricated. As a design of the tip of the sensor, non-opening type and opening type have been fabricated and the opening design decrease influence by external force such as load or the balloon inflation on catheter down to 1 - 2 mmHg and achieved error range ±3 mmHg in the pressure measurement range of 0 - 100 mmHg.

Perfusion and visceral organ protection in patients with thoraco-abdominal aneurysm repair – our experiences

Methods We conducted a retrospective observational analysis of our experience with different approaches and perfusion techniques in patients with thoraco-abdominal aneurysm. Group 1: 3 patients: aortic cross-clamp, with left heart bypass, without selective organ perfusion Group 2: 2 patients: aortic cross-clamp, without left heart bypass, selective organ perfusion Group 3: 1 patient: aortic cross-clamp, with left heart bypass, selective organ perfusion Group 4: 2 patients: aortic cross-clamp, without left heart bypass, without selective organ perfusion

Early and Late Results of Graft Replacement for Dissecting Aneurysm of Thoracoabdominal Aorta in Patients With Marfan Syndrome

When treating dissecting aneurysm of the thoracoabdominal aorta surgically in patients with Marfan syndrome, we have usually performed graft replacement- including the entire thoracoabdominal aorta and reconstruction of all visceral branches, even if dilatation is mild in some segments-to avoid further aortic operations in the follow-up period. From October 1999 through July 2011, 20 consecutive patients with Marfan syndrome underwent repair of dissecting aneurysm of the thoracoabdominal aorta (median age, 45 years; range, 19-65 years). All patients underwent surgical intervention with cerebrospinal fluid (CSF) drainage and distal aortic and selective organ perfusion. Deep hypothermia was used in 13 patients for spinal cord protection. No in-hospital mortality was observed. One patient had temporary spinal cord ischemia but was fully recovered by discharge. Other complications included exploration for bleeding (n=1), prolonged ventilation (n=1), and graft infection (n=1). At a mean follow-up of 54 months (range, 9-129 months), 1 patient had died of interstitial pneumonia at 38 months postoperatively. Survival at 8% years was 91.2±9.0%. Two patients required additional aortic procedures (total arch replacement and aortic valve-sparing surgery). Actuarial rate of freedom from aortic operations at 8 years was 83.9%±10.5%, but no patient needed required repeated thoracotomy for an aortic procedure. Neither false nor patch aneurysms were observed using computed tomography (CT) during follow-up surveillance. Graft replacement for dissecting aneurysm of the thoracoabdominal aorta in Marfan syndrome offers good early and long-term results. We believe total aortic replacement including the entire thoracoabdominal aorta and reconstruction of all visceral arteries should be recommended for selected patients with Marfan syndrome.

Simultaneous Individually Controlled Upper and Lower Body Perfusion for Valve-Sparing Root and Total Aortic Arch Replacement: A Case Study

Optimal perfusion strategies for extensive aortic resection in patients with mega-aortic syndromes include: tailored myocardial preservation, antegrade cerebral perfusion, controlled hypothermia and selective organ perfusion. Typically, the aortic arch resection and elephant trunk procedure are performed under hypothermic circulatory arrest with myocardial and cerebral protection. However, mesenteric and systemic ischemia occur during circulatory arrest and commonly rely upon deep hypothermia alone for metabolic protection. We hypothesized that simultaneously controlled mesenteric and systemic perfusion can attenuate some of the metabolic debt accrued during circulatory arrest, which may help improve perioperative outcomes. The perfusion strategy consisted of delivering a 1 to 3 liter per minute flow at 25°C to the head/upper body via right axillary graft and simultaneous perfusion to the lower body/mesenteric organs of 1 to 3 liters per minute at 30°C via a right femoral arterial graft. We describe our technique of simultaneous mesenteric, systemic, cerebral and myocardial perfusion, and protection utilized for a young male patient with Marfan’s syndrome, while undergoing a valve sparing root replacement, total arch replacement and elephant trunk reconstruction. This perfusion technique allowed us to deliver differential flow rates and temperatures to the upper and lower body (cold head/warm lower body perfusion) to minimize ischemic debt and quickly reverse metabolic derangements.

Perfusion and Aortic Surgery: Patient Directed Cardiopulmonary Bypass and Quality Improvement

Aortic surgery frequently extends the boundaries of perfusion knowledge learned from non aortic cardiac surgery. This is due to the extremes of temperature, prolonged bypass times, hypothermic arrest, and selective organ(s) perfusion. Suboptimal perfusion can potentially affect outcomes even after technically successful aortic surgery. We present the concepts of patient directed bypass with regard to blood pressure, flow during cardiopulmonary bypass (CPB), oxygen delivery, cooling, and carbon dioxide levels on bypass. Quality of perfusion during aortic surgery is then addressed in the context of Perfusion Standards of Reporting Trials (PERFSORT, www.perfsort.net). PERFSORT analyses these variables during bypass: blood pressure, hematocrit, lactate, glucose, and temperature, all of which are known to affect outcomes. PERFSORT can be applied to individual cases or a series, and although primarily designed for research publications, is equally useful in a purely clinical setting. A new concept from engineering called Lissajous figures is then discussed to potentially retrospectively assess the effects of ischemia during aortic surgery. This may help identify why some patients despite flawless surgery, anesthesia, and perfusion, in the absence of bleeding, stroke, and obvious causes of organ damage at the time of aortic surgery develop multi organ dysfunction.

Does low-flow selective organ perfusion reduce oxidative stress and inflammatory reaction following hypothermic circulatory arrest?

Does low-flow selective organ perfusion reduce oxidative stress and inflammatory reaction following hypothermic circulatory arrest?

Brain and spinal cord protection during simultaneous aortic arch and thoracoabdominal aneurysm repair

We assessed the surgical and neurological outcome of patients undergoing simultaneous repair of aortic arch and descending thoracic aortic aneurysms (DTAA) or thoracoabdominal aortic aneurysms (TAAA) via left thoracotomy or thoracolaparotomy. During a 6-year period, we performed 32 procedures in 23 male and 9 female patients with DTAA or TAAA with concomitant aortic arch aneurysms. The mean age of the patients was 50.9 years (range, 18-75 years). Twenty-two patients suffered from DTAA, 4 had type-I TAAA, and 6 had type-II TAAA. The entire aortic arch was involved in 12 patients and the distal hemi-arch in 20 patients. The mean diameter of the aneurysms was 6 cm (range, 4.9-7.6 cm). All patients were operated on according to the protocol with cerebrospinal fluid drainage, distal aortic and selective organ perfusion, as well as antegrade brain perfusion. Neuromonitoring was performed by means of motor evoked potentials (MEPs), transcranial Doppler (TCD), and electroencephalography (EEG). All patients survived the surgical procedure and 30-day mortality did not occur. At the end of the procedure, all patients had adequate MEPs, TCD, and EEG. One patient died 47 days after operation due to gastrointestinal bleeding and therapy-resistant coagulopathy. Major postoperative complications like paraplegia or paraparesis, renal failure, and myocardial infarction were not encountered. One patient had a stroke but neurological deficits were irrelevant. Mean preoperative creatinine level was 125 mmol/L, which peaked to a mean maximal level of 130 and returned to 92 mmol/L at discharge. Other complications included bleeding requiring surgical intervention (n = 4), arrhythmia (n = 1), pneumonia (n = 5), and respiratory distress syndrome (n = 2). At a median follow-up of 38 months, all but 1 patient was alive and free of re-intervention. Single-stage repair of aortic arch and concomitant thoracic and thoracoabdominal aortic aneurysms via left-sided thoracotomy or thoraco-laparotomy yields excellent short- and midterm outcomes. Monitoring of cerebral and spinal cord function contributes to improved neurologic outcome.

Visceral Injury and Systemic Inflammation in Patients Undergoing Extracorporeal Circulation During Aortic Surgery

Visceral injury and inflammation are evaluated in patients undergoing extracorporeal circulation (ECC) either with distal aortic perfusion (DAP) during thoracic aortic aneurysm (TAA) repair or DAP and selective organ perfusion (DAP and SP) during thoracoabdominal aortic aneurysm (TAAA) repair. Visceral hypoperfusion and subsequent visceral injury, mainly to the gut, have been implicated as central events in the development of systemic inflammatory response syndrome (SIRS) and organ dysfunction after major surgery. Patients undergoing DAP or DAP and SP are exposed to artificial visceral perfusion, potentially leading to the development of intestinal injury and systemic inflammation. To assess visceral injury arteriovenous differences of fatty acid binding proteins were measured for the gut (I-FABP and L-FABP) and left kidney (L-FABP) along with systemic plasma concentrations. Systemic ALT was used as liver injury marker. Plasma IL-6 and IL-8 denoted systemic inflammation. During ECC systemic I-FABP and L-FABP levels increased in both groups, representing intestinal injury. Significantly elevated levels of I-FABP (P < 0.001) and L-FABP (P < 0.001) were found in the DAP and SP group, after ECC was stopped and normal circulation restored. Liver and renal tubular cell injury was not detected. Significant increases in systemic IL-6 and IL-8 values were measured only in patients undergoing DAP and SP. Additionally, the extent of intestinal injury correlated positively with systemic inflammation. This study shows the development of intestinal mucosal injury during ECC with DAP or DAP and SP, indicative of insufficient intestinal perfusion. Intestinal injury was associated with a systemic pro-inflammatory response.

Thoracoabdominal Aortic Aneurysm Repair in Patients with Marfan Syndrome

We assessed the surgical outcome of descending thoracic aortic aneurysm repair (DTAA) and thoracoabdominal aortic aneurym (TAAA) repair in patients with Marfan syndrome. During a six year period, 206 patients underwent DTAA and TAAA repair. In 22 patients, Marfan syndrome was confirmed. The median age was 40 years with a range between 18 and 57 years. The extend of the aneurysms included 6 DTAA (1 with total arch, 2 with distal hemi-arch), 11 type II TAAA (2 with total arch, 3 with distal hemi-arch), 4 type III and one type IV TAAA. All patients suffered from previous type A (n=6) or type B (n=16) aortic dissection and 15 already underwent aortic procedures like Bentall (n=7) and ascending aortic replacement (n=8). All patients were operated on according to the standard protocol with cerebrospinal fluid drainage, distal aortic and selective organ perfusion and monitoring motor evoked potentials. In patients undergoing simultaneous arch replacement (via left thoracotomy), transcranial Doppler and EEG assessed cerebral physiology during antegrade brain perfusion. In four patients circulatory arrest under moderate hypothermia was required. In-hospital mortality did not occur. Major postoperative complications like paraplegia, renal failure, stroke and myocardial infarction were not encountered. Mean pre-operative creatinine level was 125mmol/L, which peaked to a mean maximal level of 130 and returned to 92mmol/L at discharge. Median intubation time was 1.5 days (range 0.33-30 days). Other complications included bleeding requiring surgical intervention (n=1), arrhythmia (n=2), pneumonia (n=2) and respiratory distress syndrome (n=1). At a median follow-up of 38 months all patients were alive. Using CT surveillance, new or false aneurysms were not detected, except in one patient who developed a visceral patch aneurysm six years after open type II repair. Surgical repair of descending and thoracoabdominal aortic aneurysms provides excellent short- and mid-term results in patients with Marfan syndrome. In this series, a surgical protocol with cerebrospinal fluid drainage, distal aortic and selective organ perfusion and monitoring motor evoked potentials resulted in low morbidity and absent mortality. These outcomes of open surgery should be considered when discussing endovascular aneurysm repair in Marfan patients.

The value of motor evoked potentials in reducing paraplegia during thoracoabdominal aneurysm repair

Paraplegia after thoracoabdominal aortic aneurysm (TAAA) repair mainly occurs in patients with Crawford extent I and II. We assessed the impact of monitoring spinal cord integrity and the subsequent adjusted surgical maneuvers on neurologic outcome in repairs of type I and II TAAAs. Surgical repair of TAAAs was performed in 112 consecutive patients with extent type I (n = 42) and type II (n = 70) aneurysms. The surgical protocol included cerebrospinal fluid drainage, moderate hypothermia, and left heart bypass with selective organ perfusion. Spinal cord function was assessed by means of monitoring motor evoked potentials (MEPs). Significant decreased MEPs always generated adjustments, including raising distal aortic and mean arterial pressure, reattachment of visible intercostal arteries, or endarterectomy of the excluded aortic segment with revascularization of back bleeding intercostal arteries. Motor evoked potential monitoring could be achieved in all patients. By maintaining a mean distal aortic pressure of 60 mm Hg, MEPs were adequate in 82% of patients. Increasing distal aortic pressure restored MEPs in all patients. In 19 patients (17%), MEPs decreased significantly during aortic cross-clamping because of critical spinal cord ischemia. MEPs returned in all patients after spinal cord blood flow was re-established except in three patients with type II TAAA in whom MEPs could not be restored, and absent MEPs at the end of the procedure corresponded with neurologic deficit. Delayed paraplegia developed in two patients owing to hemodynamic instability with insufficient mean arterial blood pressure to maintain adequate spinal cord perfusion. Monitoring MEPs is a highly reliable technique to assess spinal cord ischemia during TAAA repair. A surgical protocol including cerebrospinal fluid drainage, left heart bypass, and monitoring of MEPs can reduce the paraplegia rate significantly. Adjusted hemodynamic and surgical strategies induced by changes in MEPs could restore spinal cord ischemia in most patients, preventing early and late paraplegia in all type I patients. In type II patients, early paraplegia occurred in 4.2% and delayed neurologic deficit in 2.9%. Despite all available measures, complete prevention of paraplegia in type II aneurysms seems to be unrealistic.

Visceral and Renal Tissue Oxygenation During Supraceliac Aortic Crossclamping and Left Heart Bypass with Selective Organ Perfusion

Introduction. Left-heart bypass (LHB) and selective organ perfusion (SOP) are used during thoracoabdominal aortic surgery to prevent ischemic damage to the kidneys and visceral organs after supraceliac aortic crossclamping. We studied the hypothesis, in a porcine model, that despite LHB and maximal SOP, visceral and renal ischemia still occured during surgery.Material and methods. Eleven pigs (54–70 kg) were coupled to a non-pulsatile LHB with inflow and outflow at the lower thoracic and distal infrarenal aorta, respectively. After supracoeliac and infrarenal aortic crossclamping, SOP was started using perfusion catheters. The proximal and distal mean aortic blood pressures were kept above 70 and 50 mmHg, respectively, while the mean blood pressure within the SOP system was above 60 mmHg. The visceral and renal tissue oxygenation was measured by intermittent blood gas analysis, from the portal and both renal veins. The jejunal mucosal oxygenation was measured by tonometric measurement of the luminal pCO2.Results. Measured median blood blood flow through the LHB and the SOP system were 800 and 1140 ml/min, respectively. Median blood flow prior to, and during LHB and SOP through the celiac artery, superior mesenteric artery, and left renal artery were 300 and 240, 762 and 295, and 235 and 235 ml/min, respectively. During 3 h of LHB and SOP no significant changes in the renal tissue oxygenation were noted compared with the physiological situation prior to supracoeliac aortic crossclamping and cannulation. However, in the visceral vascular bed median mixed venous oxygen saturation dropped from 79 to 63% (p<0.001), and median oxygen extraction ratio increased from 26 to 41% (p<0.001). Median tonometric measured intraluminal jejunal pCO2 increased from 9.9 to 12.15kPa (p>0.05). During 3 h of LHB and SOP no hemolysis was detected, as there was no rise in serum LDH.Conclusion. LHB and SOP preserves renal but not visceral tissue oxygenation during supraceliac aortic crossclamping and does not induce hemolysis.

Reduced renal failure following thoracoabdominal aortic aneurysm repair by selective perfusion.

Renal failure and visceral ischemia are feared complications following thoracoabdominal aortic aneurysm (TAAA) repair, significantly contributing to mortality. This prospective study describes volume- and pressure-controlled perfusion of the renal and visceral arteries during TAAA surgery. In 73 consecutive patients (mean age 59 years), TAAA repair (27 type I, 28 type II, 8 type III and 10 type IV) was performed, using retrograde and selective organ perfusion. Sixteen patients had impaired renal function with blood creatinine higher than 100 mmol/l. During the thoracic part of the procedure, the mean distal aortic pressure was kept above 60 mm Hg by means of left-heart bypass. After opening the abdominal aorta, the renal and visceral arteries were individually perfused by means of perfusion catheters (9 French) in the first 33 patients (group I). Volume flow through each catheter was assessed with ultrasound flow meters and maintained at least at 60 ml/min. In addition to volume flow measurements, catheters with pressure sensors were used in the last 40 patients (group II), allowing pressure-controlled selective perfusion. The extent of the aneurysm was comparable in both groups. Mean cross-clamp time for the thoracic part was 46 min, including proximal anastomosis and reattachment of intercostal arteries. Mean cross-clamp time for the abdominal part was 74 min, including re-implantation of intestinal and renal arteries and selective dacron grafts to the celiac-axis arteries (n = 5), superior mesenteric arteries (n = 8) and renal arteries (n = 25), through which the catheters guaranteed continuous perfusion during the time the anastomosis was performed. Urine output was uninterrupted in all patients, irrespective of cross-clamp time. In group I, one patient (3%) developed renal failure and three patients (9%) required temporary peritoneal dialysis. In group II, no patients developed renal failure and two patients (5%) required temporary peritoneal dialysis. Thirteen patients with pre-existing renal impairment did not deteriorate. No patients developed visceral ischemia or multiple-organ failure. Total in-hospital mortality was 6/73 (8%) and was related to cardiopulmonary complications. Renal and visceral ischemia can be reduced significantly by continuous perfusion during cross-clamping in TAAA repair. Not only sufficient volume flow but also adequate arterial pressure appears to be essential in maintaining renal function.

Initial experience with the Nikkiso centrifugal pump during thoracoabdominal aortic aneurysm repair

Purpose: Several centers use atriodistal bypass (ADB) as a protective adjunct against distal ischemia during extensive thoracoabdominal aortic aneurysm (TAAA) repair. Most current ADB circuits use indirect-drive centrifugal pumps. The purpose of this report is to describe our initial clinical experience with the Nikkiso pump, a more compact direct-drive centrifugal pump recently developed at Baylor, for ADB during TAAA repair. Methods: The Nikkiso pump was used for ADB perfusion in 10 consecutive patients during graft repair of TAAAs (six Crawford extent I and four extent II). Two patients had aortic dissection. In the four patients who had extent II repairs, selective renal and visceral perfusion was also performed with the Nikkiso pump. Results: No mechanical pump malfunctions or adverse events related to the device occurred. All 10 patients survived and were discharged from the hospital. No patient had paraplegia after surgery. Two patients had delayed lower extremity weakness after undergoing extent I repairs; both recovered and were ambulating at the time of discharge. No complications were associated with bleeding or cerebral, respiratory, renal, or hepatic function. Conclusions: Our initial experience with the Nikkiso centrifugal pump during TAAA repair demonstrated excellent pump function that provided sufficient flow for both distal aortic and selective organ perfusion. The prevention of permanent spinal cord injury and distal organ failure was successful in this group. (J Vasc Surg 1998;27:378-83.)

Retrograde aortic and selective organ perfusion during thoracoabdominal aortic aneurysm repair

To evaluate the possible prevention of renal and intestinal ischaemia during surgery of thoracoabdominal aortic aneurysms (TAAA) by use of retrograde and selective organ perfusion. Prospective study. Thirty-three consecutive patients underwent TAAA repair, six of whom had a previous type B dissection: 14 patients (35%) had type I TAAA, 12 patients type II (32%), three patients type III (15%) and four patients type IV (18%). Mean age was 61 years (range 22-84 years). In patients with type I TAAA, retrograde aortic perfusion was performed by means of a left atrium femoral artery bypass or partial cardiopulmonary bypass. In type II, III and IV the same procedure was performed; however, following cross-clamping and opening of the abdominal aorta, the coeliac trunc, superior mesenteric and both renal arteries were selectively perfused with four Pruitt-catheters (9 Fr.), connected as an octopus to the extracorporal circulation. All patients survived the surgical procedure. The minimal volume flow through each octopus catheter was 60 ml/min. Urine output was uninterrupted in all patients, irrespective of the aortic cross-clamp time. Only one patient (3%), who already had renal insufficiency, developed renal failure. Total in-hospital mortality was 15%, paraplegia occurred in 12%. Retrograde aortic and selective organ perfusion is a safe technique and can prevent ischaemic renal and intestinal damage during cross-clamping of the aorta in thoracoabdominal aneurysm surgery.