Cardiopulmonary Bypass Perfusion Research Articles

Multicenter National survey on Cardiopulmonary bypass (CPB) Perfusion Practices during adult cardiac surgery

Multicenter National survey on Cardiopulmonary bypass (CPB) Perfusion Practices during adult cardiac surgery

Using Machine Learning to Predict Bleeding after Cardiac Surgery.

The primary objective was to predict bleeding after cardiac surgery with machine learning using the data from the ANZSCTS (Australia New Zealand Society of Cardiac and Thoracic Surgeons) Cardiac Surgery Database, cardiopulmonary bypass perfusion database, ICU (intensive care unit) database and laboratory results. We obtained surgical, perfusion, ICU and laboratory data from a single Australian tertiary cardiac surgical hospital from February 2015 to March 2022 and included 2000 patients undergoing cardiac surgery. We trained our models to predict either the Papworth definition or Dyke et al.'s universal definition of perioperative bleeding. Our primary outcome was the performance of our machine learning algorithms using sensitivity, specificity, positive and negative predictive values, accuracy, AUROC (area under receiver operating characteristics curve) and AUPRC (area under precision recall curve). Of the 2000 patients undergoing cardiac surgery, 13.3% (226/2000) had bleeding using the Papworth definition and 17.2% (343/2000) had moderate to massive bleeding using Dyke et al.'s definition. The best performing model based on AUPRC was the Ensemble Voting Classifier model for both Papworth (AUPRC 0.310, AUROC 0.738) and Dyke definitions of bleeding (AUPRC 0.452, AUROC 0.797). Machine learning can incorporate routinely collected data from various datasets to predict bleeding after cardiac surgery.

Recannulation of the right axillary artery in reoperative proximal thoracic aortic surgery is safe.

OBJECTIVESTo evaluate the safety and efficacy of recannulating the axillary artery in reoperative proximal thoracic aortic surgery.METHODSBetween 2008 and 2020, we evaluated patients who underwent reoperative proximal thoracic aortic surgery. The patients were divided into 2 groups: (i) patients with no previous right axillary artery cannulation (primary cannulation group) and (ii) patients with a previous cannulated right axillary artery (recannulation group). We analysed the intraoperative data, cannulation-related complications, postoperative outcomes and compared the 2 groups (primary cannulation versus recannulation).RESULTSThe patient (n = 132) baseline characteristics did not differ significantly between the 2 groups. There was no statistically significant difference in regard to the duration of surgery, cardiopulmonary bypass, aortic cross-clamp and antegrade cerebral perfusion time nor in regard to the total number of patients with cannulation-related complications between the 2 groups [n = 8 (8.0%) vs n = 1 (3.1%), P = 0.34]. The incidence of iatrogenic axillary artery dissection, iatrogenic aortic dissection, iatrogenic aortic dissection leading to death, axillary artery thrombosis, need for surgical repair, brachial plexus injury rates, malperfusion, high perfusion resistance and hyperperfusion syndrome revealed no significant difference between the 2 groups (P > 0.05). There were 11 (11.0%) cases of stroke in the primary cannulation group and 1 (3.1%) in the recannulation group (P = 0.18).CONCLUSIONSRecannulation of the right axillary artery in reoperative proximal thoracic aortic surgery is not associated with worse clinical outcomes and can be safely and effectively performed, also representing a preventive and rescue measure. Previous cannulation of the axillary artery should not hinder the decision for recannulation.

Aortic Root and Distal Arch Management During Type A Aortic Dissection Repair: Expanding Horizons.

The management of Type A aortic dissection has evolved over a period of a decade or so, and contemporary reports are suggesting a paradigm shift from a conservative approach to complete excision of the diseased aorta including root and distal arch. Improved cardiopulmonary bypass perfusion techniques, better understanding of the cerebral perfusion, and wide-ranging obtainability of prosthetic conduits gave surgical teams numerous choices. With improving outcomes and maturing surgical techniques, surgeons are performing extensive resections of the diseased aorta, but there is no standard protocol as far as the extent of the proximal and distal diseased aortic tissue resection is concerned. Aortic root replacement is associated with good early- and long-term outcomes and proffered solution in young and stable patients, for that reason many busy centres are endorsing total arch replacement in complex distal aortic dissections. This systemic review is discussing contemporary literature and associated pros and cons during surgical decision-making for these high-risk cases.

The effect of selective cerebral perfusion on cerebral versus somatic tissue oxygenation during aortic coarctation repair in neonates and infants

BackgroundSuboptimal tissue perfusion and oxygenation may be the root cause of certain perioperative complications in neonates and infants having complicated aortic coarctation repair. Practical, effective, and real-time monitoring of organ perfusion and/or tissue oxygenation may provide early warning of end-organ mal-perfusion.Methods Neonates/infants who were scheduled for aortic coarctation repair with cardiopulmonary bypass (CPB) and selective cerebral perfusion (SCP) from January 2015 to February 2017 in Children’s Hospital of Nanjing Medical University participated in this prospective observational study. Cerebral and somatic tissue oxygen saturation (SctO2 and SstO2) were monitored on the forehead and at the thoracolumbar paraspinal region, respectively. SctO2 and SstO2 were recorded at different time points (baseline, skin incision, CPB start, SCP start, SCP end, aortic opening, CPB end, and surgery end). SctO2 and SstO2 were correlated with mean arterial pressure (MAP) and partial pressure of arterial blood carbon dioxide (PaCO2).ResultsData of 21 patients were analyzed (age=75±67 days, body weight=4.4±1.0 kg). SstO2 was significantly lower than SctO2 before aortic opening and significantly higher than SctO2 after aortic opening. SstO2 correlated with leg MAP when the measurements during SCP were (r=0.67, p<0.0001) and were not included (r=0.46, p<0.0001); in contrast, SctO2 correlated with arm MAP only when the measurements during SCP were excluded (r=0.14, p=0.08 vs. r=0.66, p<0.0001). SCP also confounded SctO2/SstO2’s correlation with PaCO2; when the measurements during SCP were excluded, SctO2 positively correlated with PaCO2 (r=0.65, p<0.0001), while SstO2 negatively correlated with PaCO2 (r=-0.53, p<0.0001).Conclusions SctO2 and SstO2 have distinct patterns of changes before and after aortic opening during neonate/infant aortic coarctation repair. SctO2/SstO2’s correlations with MAP and PaCO2 are confounded by SCP. The outcome impact of combined SctO2/SstO2 monitoring remains to be studied.

In Vitro Evaluation of Flow Distribution in All-Region Perfusion during the Norwood Operation

Continuous all-region perfusion has the potential to reduce total body ischemia during the Norwood procedure. This technique involves placing cannulas in the innominate artery, descending aorta, and native aortic root, thus providing continuous flow to the whole body at mild hypothermia (32–34°C) during the entire operation. However, the cannulation strategy in this approach must be optimized to achieve adequate flow rates to all vascular beds. To ensure appropriate blood flow rates to three cannulas of different caliber supplied by two inflow pumps, a benchtop evaluation of comparative flow rates through branched cannulas with variable independent perfusion pressures was conducted. Two isolated vertical columns with outlets at 10 mmHg intervals to allow for adjustable perfusion pressures were filled with expired banked packed red blood cells and fresh frozen plasma. The main arterial line was bifurcated with an 8-Fr arterial cannula inserted at the base of one column and a 4-mm (outside diameter [OD]) olive tip cannula inserted at the base of the other column. Flow rates were measured on each branch of the ¼″ arterial lines. Under experimental cardiopulmonary bypass (CPB) perfusion pressures of 30–50 mmHg on the 8-Fr arterial cannula column, the branched olive tip cannula accommodated less than 25% of total flow at total flow rates of 50–700 mL/min. This fraction is insufficient to sustain adequate lower body perfusion. However, the olive tip flow fraction was found to be sufficient for coronary blood flow (5–20 mL/kg/min) when olive tip perfusion pressures close to average neonatal diastolic blood pressures (20–60 mmHg) were tested. For all-region perfusion during the Norwood operation, primary CPB arterial flow should be divided to the head and coronary circulation with an independent pump delivering flow to the descending aorta. This should avoid cerebral over-circulation and insufficient flow to the lower body.

In Vitro Evaluation of Flow Distribution in All-Region Perfusion during the Norwood Operation.

Continuous all-region perfusion has the potential to reduce total body ischemia during the Norwood procedure. This technique involves placing cannulas in the innominate artery, descending aorta, and native aortic root, thus providing continuous flow to the whole body at mild hypothermia (32-34°C) during the entire operation. However, the cannulation strategy in this approach must be optimized to achieve adequate flow rates to all vascular beds. To ensure appropriate blood flow rates to three cannulas of different caliber supplied by two inflow pumps, a benchtop evaluation of comparative flow rates through branched cannulas with variable independent perfusion pressures was conducted. Two isolated vertical columns with outlets at 10 mmHg intervals to allow for adjustable perfusion pressures were filled with expired banked packed red blood cells and fresh frozen plasma. The main arterial line was bifurcated with an 8-Fr arterial cannula inserted at the base of one column and a 4-mm (outside diameter [OD]) olive tip cannula inserted at the base of the other column. Flow rates were measured on each branch of the ¼″ arterial lines. Under experimental cardiopulmonary bypass (CPB) perfusion pressures of 30-50 mmHg on the 8-Fr arterial cannula column, the branched olive tip cannula accommodated less than 25% of total flow at total flow rates of 50-700 mL/min. This fraction is insufficient to sustain adequate lower body perfusion. However, the olive tip flow fraction was found to be sufficient for coronary blood flow (5-20 mL/kg/min) when olive tip perfusion pressures close to average neonatal diastolic blood pressures (20-60 mmHg) were tested. For all-region perfusion during the Norwood operation, primary CPB arterial flow should be divided to the head and coronary circulation with an independent pump delivering flow to the descending aorta. This should avoid cerebral over-circulation and insufficient flow to the lower body.

A modified frozen elephant trunk technique for acute Stanford type A aortic dissection

BackgroundAcute Stanford type A aortic dissection is often fatal, with a high mortality rate and requiring emergency intervention. Salvage surgery aims to keep the patient alive by addressing severe aortic regurgitation, tamponade, primary tear, and organ malperfusion and, if possible, prevent the late dissection-related complications in the proximal and downstream aorta. Unfortunately, no optimal standard treatment or technique to treat this disease exists. Total arch replacement with frozen elephant trunk technique plays an important role in treating acute type A aortic dissection. We aim to describe a modified elephant trunk technique and report its short-term outcomes.MethodsFrom February 2018 to August 2019, 16 patients diagnosed with acute Stanford type A aortic dissection underwent surgery with the modified frozen elephant trunk technique at Xiamen Heart Center (male/female: 9/7; average age: 56.1 ± 7.6 years). All perioperative variables were recorded and analyzed. We measured the diameters of the ascending aorta, aortic arch, and descending aorta on the bifurcation of the pulmonary and abdominal aortas and compared the diameters at admission, before discharge, and 3 months after discharge.ResultsFifteen patients (93.8%) had hypertension. The primary tears were located in the lesser curvature of the aortic arch and ascending aorta in 5 (31.3%) and 9 patients (56.3%), respectively, and no entry was found in 2 patients (12.5%). The dissection extended to the iliac artery and distal descending aorta in 14 (87.6%) and 2 patients (12.5%), respectively. The duration of cardiopulmonary bypass (CPB), cross-clamping, and antegrade cerebral perfusion were 215.8 ± 40.5, 140.8 ± 32.3, and 55.1 ± 15.2 min, respectively. Aortic valve repair was performed in 15 patients (93.8%). Bentall procedure was performed in one patient (6.3%). Another patient received coronary artery repair (6.3%). The diameters at all levels were greater on discharge than those on admission, except the aortic arch. After 3 months, the true lumen diameter distal to the frozen elephant trunk increased, indicating false lumen thrombosis and/or aortic remodeling.ConclusionsThe modified frozen elephant trunk technique for acute Stanford type A aortic dissection is safe and feasible and could be used for organ malperfusion. Short-term outcomes are encouraging, but long-term outcomes require further investigation.

Repair of residual aortic dissections with frozen elephant trunk technique

In this study, we present our mid-term results of reoperation with the frozen elephant trunk procedure due to patent false lumen-related complications in patients previously undergoing supracoronary aortic repair for acute type A aortic dissection. Between January 2013 and September 2018, a total of 23 patients (17 males, 6 females; mean age 51.5±9.7 years; range, 30 to 67 years) who underwent ascending aortic replacement due to type A aortic dissection and, later, frozen elephant trunk procedure for residual distal dissection were included. For diagnostic purposes and follow-up, computed tomography angiography was performed in all patients, and both re-entry and aortic diameters were evaluated. Echocardiography was used to evaluate cardiac function and valve pathologies. The Ishimaru zone 0 (n=11, 47.8%), Ishimaru zone 1 (n=1, 4.3%), Ishimaru zone 2 (n=4, 17.4%), and Ishimaru zone 3 (n=7, 30.4%) were used for frozen elephant trunk stent graft fixation. The mean duration of cardiopulmonary bypass and antegrade selective cerebral perfusion was 223.9±71.2 min and 88.9±60.3 min, respectively. In-hospital mortality was 13%, while there was one (4.3%) aortic-related death and four (17.4%) re-interventions during follow-up. Early repair should be considered in the presence of persistent dissections due to alarmingly high mortality rates of reoperations. Reoperation with the frozen elephant trunk procedure has acceptable results and the decision of the procedure to be performed should be based on preoperative risk factors of the patient.

Effects of cardiopulmonary bypass perfusion temperature on perioperative renal function in adult patients undergoing cardiac surgery.

Aims and objectiveThe primary objective of this investigation was to study the effects of cardiopulmonary bypass (CPB) perfusion temperature on renal function parameters [serum creatinine, creatinine clearance, urine albumin, urine protein, and urine albumin/creatinine ratio (ACR)]. The secondary objective was to detect renal complications of CPB.Materials and methodsThis is a prospective longitudinal study of 30 adult patients (17 men, 13 women; mean age, 53.37 ± 16.02 years) who underwent valvular heart surgery [with or without coronary artery bypass grafting (CABG)]. Serum creatinine, creatinine clearance, urine protein, urine albumin, and urine ACR were collected during CPB (at 28 °C, 32 °C, and 37 °C) and postoperatively (at 12 hours, 24 hours, and 48 hours). Data were analyzed using one-way repeated-measures analysis of variance (ANOVA). A significant ANOVA was followed by a Bonferroni–Holm post hoc test.ResultsAlthough serum creatinine (p < 0.001) and creatinine clearance (p = 0.0016) underwent a significant ANOVA change (p < 0.001 and p = 0.0016, respectively) after CPB, there was no statistically significant change compared with their baseline values. Urine ACR showed a significant change at 28 °C (p < 0.01), 32 °C (p < 0.01), and 37 °C (p < 0.05) as compared with baseline values. No significant change in urine albumin was observed during CPB or up to 24 hours. A significant change occurred after 48 hours of CPB (p < 0.05). A significant increase in urine protein was noted after CPB at 12 hours (p < 0.01), 24 hours (p < 0.01), and 48 hours (p < 0.01). Overall, 12 (40%) patients had acute kidney injury (AKI). Ten (33.33%) patients had stage I AKI, one patient progressed to AKI stage II, and another to AKI stage III. Of the 10 patients who had stage I AKI, eight had complete recovery within 48 hours.ConclusionsCPB with moderate hypothermia for valvular heart surgeries can be performed safely in patients with adequate renal functional reserve. The glomerular permeability across the Bowman’s capsule increases after CPB as evidenced by significant proteinuria at 12 hours and increased albuminuria at 48 hours after surgery. There is an increased risk of transient stage I AKI after CPB, from which patients recover within 48 hours.

Early outcome of aortic balloon occlusion during total aortic arch replacement with the frozen elephant trunk technique for aortic dissection.

The aim of this study was to propose and evaluate the new operative technique of aortic balloon occlusion in total aortic arch replacement (TAR) with the frozen elephant trunk that can significantly decrease the time of circulatory arrest and increase the hypothermic cardiopulmonary bypass (CPB) temperature. Between 2010 and 2018, 1335 patients with aortic dissection who underwent TAR with the frozen elephant trunk were included in the study. The newest 80 cases were treated with aortic balloon occlusion. To illustrate the difference with the new procedure, 1255 conventional TAR cases served as the historical control. Femoral and right axillary artery cannulations were used for CPB and antegrade selective cerebral perfusion. Circulatory arrest was implemented at the nasopharyngeal temperature of 28°C with continuous antegrade selective cerebral perfusion. After the stent graft was inserted into the true lumen of the descending aorta, the aortic balloon in a sheath was deployed into the stent graft and positioned at the metal part of the stent graft. When the balloon was inflated with enough saline to compress the stent graft, the sheath was simultaneously pressed by hand to properly fix the balloon and avoid displacement. Then femoral perfusion could be resumed. The aortic balloon occlusion technique was successful in all patients, with the median duration of circulatory arrest being 5 (interquartile range 3-7) min. The 30-day mortality rate was 6.25% (5/80), whereas with the conventional method it was 9.40% (118/1255). The postoperative conscious revival (8.67 vs 11.40 h, P < 0.001) and mechanical ventilation times (19.70 vs 24.45 h, P = 0.02) were significantly shorter. Decreases in postoperative acute kidney injuries (13.75% vs 32.11%, P = 0.001) and liver injuries (8.75% vs 37.61%, P < 0.001) were also observed. The patients were transfused with lesser quantities of red blood cells, plasma and platelets. The aortic balloon occlusion technique is a feasible way to shorten circulatory arrest significantly, to obviate the need for deep hypothermia in TAR with the frozen elephant trunk and to provide favourable protective effects on the central nervous, haematological and visceral systems. With these satisfactory results, this technique deserves further investigation.

Effects of cardiopulmonary bypass perfusion temperature on perioperative renal function in adult patients undergoing cardiac surgery

Aims and objectiveThe primary objective of this investigation was to study the effects of cardiopulmonary bypass (CPB) perfusion temperature on renal function parameters [serum creatinine, creatinine clearance, urine albumin, urine protein, and urine albumin/creatinine ratio (ACR)]. The secondary objective was to detect renal complications of CPB. Materials and methodsThis is a prospective longitudinal study of 30 adult patients (17 men, 13 women; mean age, 53.37 ± 16.02 years) who underwent valvular heart surgery [with or without coronary artery bypass grafting (CABG)]. Serum creatinine, creatinine clearance, urine protein, urine albumin, and urine ACR were collected during CPB (at 28 °C, 32 °C, and 37 °C) and postoperatively (at 12 hours, 24 hours, and 48 hours). Data were analyzed using one-way repeated-measures analysis of variance (ANOVA). A significant ANOVA was followed by a Bonferroni–Holm post hoc test. ResultsAlthough serum creatinine (p < 0.001) and creatinine clearance (p = 0.0016) underwent a significant ANOVA change (p < 0.001 and p = 0.0016, respectively) after CPB, there was no statistically significant change compared with their baseline values. Urine ACR showed a significant change at 28 °C (p < 0.01), 32 °C (p < 0.01), and 37 °C (p < 0.05) as compared with baseline values. No significant change in urine albumin was observed during CPB or up to 24 hours. A significant change occurred after 48 hours of CPB (p < 0.05). A significant increase in urine protein was noted after CPB at 12 hours (p < 0.01), 24 hours (p < 0.01), and 48 hours (p < 0.01). Overall, 12 (40%) patients had acute kidney injury (AKI). Ten (33.33%) patients had stage I AKI, one patient progressed to AKI stage II, and another to AKI stage III. Of the 10 patients who had stage I AKI, eight had complete recovery within 48 hours. ConclusionsCPB with moderate hypothermia for valvular heart surgeries can be performed safely in patients with adequate renal functional reserve. The glomerular permeability across the Bowman’s capsule increases after CPB as evidenced by significant proteinuria at 12 hours and increased albuminuria at 48 hours after surgery. There is an increased risk of transient stage I AKI after CPB, from which patients recover within 48 hours.

Differences of early immunological responses in on-pump versus off-pump cardiac surgery.

Cardiopulmonary bypass surgery is accompanied by an inflammatory response and pulmonary dysfunction that renders patients vulnerable to postoperative complications. The majority of studies investigating the inflammatory response in cardiopulmonary bypass focus on cytokine measurements. This study investigated the early response of peripheral blood cell types and early changes in lung tissue in on-pump versus off-pump cardiopulmonary bypass surgery. Landrace pigs were assigned to the following groups (n = 6 per group): 1. off-pump cardiopulmonary bypass, 2. conventional cardiopulmonary bypass, 3. heparin-coated cardiopulmonary bypass, 4. surface-reduced cardiopulmonary bypass, and 5. surface-reduced cardiopulmonary bypass plus lung perfusion. Surgery was performed under mild hyperthermia (32°C), with 90-minute ischemia and 180-minute reperfusion. Histological and flow cytometric analyses were performed. Lung water content increased during reperfusion in heparin-coated (84.63 ± 2.99%) compared to conventional cardiopulmonary bypass (76.33 ± 4.56%, p = 0.04). Alveolar septal thickness increased during ischemia at heparin-coated (p < 0.01) and surface-reduced cardiopulmonary bypass plus lung perfusion (p = 0.05). Tumor necrosis factor expression increased significantly (p < 0.01) in peribronchial, perivascular, and peripheral lung areas in all on-pump groups, but not in off-pump cardiopulmonary bypass. The usage of heparin-coated cardiopulmonary bypass led to increased percentages of CD3+CD4+ (p = 0.03) and CD3+CD8+ (p = 0.01) T cells compared to an uncoated device. Natural killer and mature B lymphocytes decreased at conventional and surface-reduced cardiopulmonary bypass plus lung perfusion. Activated granulocytes and macrophages increased at conventional cardiopulmonary bypass and heparin-coated cardiopulmonary bypass. Off-pump cardiopulmonary bypass induces less immunological response and lung injury than on-pump surgery. The reduction of cardiopulmonary bypass surface reduces the inflammatory immune response induced by cardiopulmonary bypass. Lung perfusion of surface-reduced cardiopulmonary bypass diminished the extravasation caused by surface reduction of the cardiopulmonary bypass.

A Review of Goal-Directed Cardiopulmonary Bypass Management in Pediatric Cardiac Surgery.

Cardiopulmonary bypass perfusion management significantly affects postoperative outcomes. In recent years, the principles of goal-directed therapy have been applied to the field of cardiothoracic surgery to improve patient outcomes. Goal-directed therapy involves continuous peri- and postoperative monitoring of vital clinical parameters to tailor perfusion to each patient's specific needs. Closely measured parameters include fibrinogen, platelet count, lactate, venous oxygen saturation, central venous oxygen saturation, mean arterial pressure, perfusion flow rate, and perfusion pulsatility. These parameters have been shown to influence postoperative fresh frozen plasma transfusion rate, coagulation state, end-organ perfusion, and mortality. In this review, we discuss the recent paradigm shift in pediatric perfusion management toward goal-directed perfusion.

Recent innovations in perfusion and cardiopulmonary bypass for neonatal and infant cardiac surgery.

The development and refinement of cardiopulmonary bypass (CPB) has made the repair of complex congenital heart defects possible in neonates and infants. In the past, the primary goal for these procedures was patient survival. Now that substantial survival rates have been achieved for even the most complex of repairs in these patients, focus has been given to the reduction of morbidity. Although a necessity for these complex neonatal and infant heart defect repairs, CPB can also be an important source of perioperative complications. Recent innovations have been developed to mitigate these risks and is the topic of this review. Specifically, we will discuss improvements in minimizing blood transfusions, CPB circuit design, monitoring, perfusion techniques, temperature management, and myocardial protection, and then conclude with a brief discussion of how further systematic improvements can be made in these areas.

A Novel Interoperable Safety System for Improved Coordination and Communication in Cardiac Surgery.

During cardiac surgery there is an unmet need for safe transfer of responsibility for patient oxygenation back and forth from the anesthesia to the perfusion teams. Prior to cardiopulmonary bypass (CPB), lung ventilation is performed by the anesthesia machine ventilator and is the responsibility of the anesthesia team. During CPB, lung ventilation is halted and oxygenation is performed by the CPB oxygenator and perfusion team This recurrent transfer throughout the procedure introduces the rare but serious possibility of a "never event", resulting in the patient's lungs not being ventilated upon stopping the CPB and potentially leading to catastrophic hypoxemia. Monitors and alarms on the anesthesia and bypass machines would not be useful when the other device is operating so they are routinely put into a standby mode until needed. Consequently, in the event that the handoff is missed, there are no alarms to catch the situation. To solve this unmet need, we propose a novel interoperable, context-aware system capable of detecting and acting if this rare situation occurs. Our system is built on the open-source OpenICE framework, allowing it to seamlessly work with a variety of ventilator and bypass machines.

Isolated Perfusion of the Upper Extremity with TNF-α - Double Venous Cannulation

The authors present a technical variation of the standard cannulation for cardiopulmonary bypass perfusion during hyperthermic isolated limb perfusion (ILP) procedures in selected patients with unresectable soft tissue sarcoma or malignant melanoma. Of 55 ILP procedures performed at our institution since the procedure was established in 2009, nine were performed at the upper extremity. Standard single venous cannulation was used in five cases, and extended, double venous cannulation in the last four. The standard technique for brachial vein cannulation in a small compartment of the upper extremity entails a problematic and longer perfusion of the upper extremity. This is due to the lower flow rate in the venous system and relatively large surface area with respect to weight. We present a simple technique based on a "Y" cannulation of the venous system via the deep brachial vein and superficial venous system via the basilic vein, delivering a 20% increase in flow rate in the extracorporeal circulation. Faster heating of the upper extremity and a stable thermal environment throughout upper-extremity ILP are essential for successful treatment. Extended technique of venous cannulation for extracorporeal circulation setting, due to their advantages, became standard in the upper limb ILP procedure at our institution.Key words: isolated limb perfusion - malignant melanoma - soft tissue sarcoma - upper limb - extracorporeal circulation The authors declare they have no potential conflicts of interest concerning drugs, products, or services used in the study. The Editorial Board declares that the manuscript met the ICMJE recommendation for biomedical papers.Submitted: 8. 1. 2017Accepted: 15. 1. 2017.

Invited Commentary

I would like to congratulate Elvevoll and colleagues [1Elvevoll B. Lundemoen S. Svendsen O.S. et al.Does roller pump-induced pulsatile CPB perfusion affect microvascular fluid shifts and tissue perfusion?.Ann Thorac Surg. 2016; 102: 564-572Abstract Full Text Full Text PDF PubMed Scopus (3) Google Scholar] for this well thought out trial. Although the size of the aortic cannula does restrict the pulsatile wave form, I think it is still a valid model. The use of microspheres also adds validity to the model and to its results: no difference in pulsatile versus nonpulsatile flow. Pulsatile flow is the most efficient means for our body to power the cardiovascular system, but it is not necessary. This is shown clinically by the success of second-generation mechanical assist devices. The most energy demanding of patients, the pediatric population, grow and thrive on both pulsatile and nonpulsative devices. Hopefully the “golden calf” of pulsatility will soon be slain with device companies focusing on smaller devices and research dollars funneled toward better understanding the nuances of an individuals’ coagulation cascade. Does Roller Pump–Induced Pulsatile CPB Perfusion Affect Microvascular Fluid Shifts and Tissue Perfusion?The Annals of Thoracic SurgeryVol. 102Issue 2PreviewPulsatile versus nonpulsatile cardiopulmonary bypass (CPB) perfusion remains debated. Beneficial effects on tissue perfusion, inflammation, and microvascular fluid exchange have been linked to pulsatile perfusion by some investigators and denied by others. This study evaluated fluid extravasation and tissue perfusion during nonpulsatile or pulsatile roller pump–induced CPB perfusion. Full-Text PDF

Lung-Centered Open Heart Surgery: A Call for a Paradigm Change.

Lung-Centered Open Heart Surgery: A Call for a Paradigm Change.

Does Roller Pump–Induced Pulsatile CPB Perfusion Affect Microvascular Fluid Shifts and Tissue Perfusion?

Pulsatile versus nonpulsatile cardiopulmonary bypass (CPB) perfusion remains debated. Beneficial effects on tissue perfusion, inflammation, and microvascular fluid exchange have been linked to pulsatile perfusion by some investigators and denied by others. This study evaluated fluid extravasation and tissue perfusion during nonpulsatile or pulsatile roller pump-induced CPB perfusion. Fourteen pigs underwent roller pump-induced pulsatile (n= 7) or nonpulsatile CPB perfusion (n= 7) for 90 minutes. Fluid input/losses, colloid osmotic pressures (plasma/interstitium), hematocrit, serum electrolytes, serum proteins, tissue perfusion, and total tissue water content were measured, and plasma volume and fluid extravasation were calculated. Fluid additions/losses, plasma volume, and fluid extravasation changed similarly in both groups during CPB with no between-group differences. Neither was between-group differences observed for tissue perfusion and total tissue water content, with one exception. Total tissue water content of the right (3.92 ± 0.26 versus 4.32 ± 0.28 g/g dry weight) and left ventricle (4.02 ± 0.25 versus 4.33 ± 0.24 g/g dry weight) was lowered in the pulsatile group. No important differences were found between pulsatile and nonpulsatile CPB perfusion for microvascular fluid balance and tissue perfusion.