Use Of Systemic Heparin Research Articles

Microsurgical training in vein anastomoses: the use of systemic heparin in a rat model.

To investigate whether the use of systemic heparin could be useful for vein microvascular anastomoses in microsurgical training on rats. Femoral end-to-end venous anastomoses were performed on both thighs of 40 wistar rats by two microsurgery trainees from October 2018 to February 2019 (80 anastomoses in total). We divided the rats into 2 groups of 20 specimens (40 femoral end-to-end anastomoses) each: group A received no heparin administration; group B received subcutaneous systemic heparin administration before starting dissection. We compared both vein patency after the procedures. Patency tests showed no difference between the two groups after 5 minutes. At the delayed test after 120 minutes, vein patency was significantly better in the systemic heparin group (85,0% vs 55,0%). Even though both trainees judged practicing on both groups very instructive, they found useful performing anastomoses when heparin was administrated. We suggest including the use of systemic heparin in microsurgery training programs, especially for the beginners. Systemic heparin administration in rat models is educative for trainees.

The Use of Heparin during Open Repair of Ruptured Abdominal Aortic Aneurysm is Safe and Reduces Mortality

Introduction: The use of systemic heparin during open repair of ruptured abdominal aortic aneurysms (rAAA) remains contentious with no clear guidelines. The purpose of this study is to investigate the effects of intraoperative heparin on perioperative outcomes after open rAAA repair. Methods: The Vascular Quality Initiative (VQI) database was queried for all patients that received open repair for rAAAs from 2011 to 2021. Perioperative outcomes included mortality, myocardial infarction, permanent dialysis, lower extremity ischemia, bowel ischemia, stroke and return to OR for any reason or for bleeding. Results: A total of 2,209 patients underwent open rAAA repair, of which, 80.7% received intraoperative heparin. Patients in the non-heparin group had significantly larger aneurysms (P = 0.044) and were more likely to be hemodynamically unstable with lower minimum systolic blood pressure and higher rates of cardiac arrest (P < 0.001). In contrast, the symptoms-to-intervention time was significantly longer in the heparin group (P = 0.002). On univariable analysis, patients in the heparin group exhibited significantly lower rates of perioperative mortality (30.4%vs59.9%, P < 0.001) and return to OR for bleeding (7.3%vs11.4%, P = 0.007). After adjustment, the use of heparin was associated with a 52% decrease in the risk of death (aOR,0.48;95% CI,0.36-0.66;P <0.001) and a 34% decrease in the risk of reexploration for bleeding (aOR,0.66;95% CI,0.46-0.94;P = 0.021). Conclusion: The use of heparin during open repair of rAAA in a real-world setting was associated with a significant decrease in the risk of death without increasing the risk of bleeding and postoperative complication. These findings suggest that the use of heparin is safe in open rAAAs.

Vascular emergencies-The new COVID-19 crisis?

Vascular emergencies-The new COVID-19 crisis?

Safety and Efficacy of a Percutaneously Inserted Ventricular Support Device Purge Solution Heparin 25 U/mL.

The Impella is a percutaneous ventricular assist device (pVAD) that provides temporary hemodynamic support to patients with cardiogenic shock or for protected percutaneous coronary intervention. The manufacturer recommends a 50-U/mL concentration of heparin purge solution (or 25 U/mL as an alternative), with systemic heparin to maintain therapeutic anticoagulation during device support. Concomitant use of systemic heparin with the purge solution may increase the risk of bleeding. The primary objective of this study was to describe the prevalence of thrombosis and bleeding using a less-concentrated heparin purge solution (25 U/mL) in combination with systemic heparin therapy. This was a retrospective observational cohort study of patients who required at least 12 hours of pVAD support and received 25-U/mL concentration of heparin purge solution between January 1, 2014, and May 31, 2017. The primary end points were the rate of thrombotic and bleeding events. Secondary end points included the percentage of time within the therapeutic activated partial thromboplastin time (aPTT) range. Descriptive statistics were utilized for data analysis. Of the 161 patients screened, 100 met inclusion criteria; 63% of patients experienced a bleeding event, with Bleeding Academic Research Consortium (BARC) type 3a being the most common. Median percentages of subtherapeutic and supratherapeutic aPTT values were similar between the bleeding and nonbleeding groups. Two patients experienced thrombotic events. Based on our findings, the device thrombosis rate was 2% and the rate of major bleeding (BARC 3a and higher) was 35%. This study provides descriptive outcomes data of a lower-concentration heparin purge solution.

Safety and Efficacy of Living Donor Hepatectomy Without Systemic Heparinization: Short- and Long-Term Outcomes

There is no consensus regarding the use of systemic heparin, and long-term outcomes of living donor hepatectomy (LDH) without systemic heparinization have not yet been determined. This study was performed to determine whether systemic heparinization can be omitted during LDH, with a focus on donor safety and long-term outcomes.We retrospectively analyzed the outcomes of 175 cases of LDH performed in our institution between January 2011 and December 2014: group I (n = 79) received systemic heparinization, whereas group II (n = 96) did not, but liver graft was flushed with a heparinized perfusate. Postoperative bleeding requiring blood transfusion or intervention was more frequent in group I than in group II (P = .028). The decreases in donor hemoglobin and hematocrit levels, and platelet count during the early postoperative period, were greater in group I than in group II. In multivariate analysis, systemic heparin was the only independent risk factor for blood transfusion (odds ratio [OR] = 5.114; 95% confidence interval [CI]: 1.201-21.775; P = .027) and significant postoperative bleeding (OR = 7.731; 95% CI: 1.345-44.429; P = .022) after LDH. Most postoperative complications including graft vascular thrombosis were similar between the 2 groups, as was the survival rate, and neither graft loss due to vascular thrombosis nor non-anastomotic biliary stricture was evident. In conclusion, omission of systemic heparinization during LDH is a feasible and safe option without adverse effects.

Successful local use of heparin calcium for congested fingertip replants.

BackgroundConventional methods of external bleeding for congested fingertip replants exhibit notable problems, including uncontrollable bleeding and unpredictable survival of the replant. We have added a local injection of heparin calcium to the routine use of systemic heparinization for inducing external bleeding. We retrospectively examined patients who underwent external bleeding using our method.MethodsLocal subcutaneous injections of heparin calcium were made in 15 congested replants in addition to systemic heparinization. Each injection ranged from 500 to 5,000 U. The average duration of the injections was 4.1 days. Surgical outcomes were analyzed and compared with a control group of patients who underwent external bleeding without heparin calcium.ResultsThe overall survival rate was 93.3%, which was higher than that of the control group (83.3%), but the difference was not statistically significant (P=0.569). The survival rate for subzones I and II by the Ishikawa subzone classification was 100%, whereas it was 87.5% in subzones III and IV. No statistically significant difference was observed. The rate of partial necrosis was 0% in subzones I and II, whereas it was significantly higher (66.7%) in subzones III and IV (P=0.015). The mean total blood loss via external bleeding was 588 g in 10 fingers. No patients required blood transfusion.ConclusionsCongestion of a replanted fingertip can be successfully managed without blood transfusion by our method. Although complete relief from congestion in replants in subzones I and II is achievable, there is a higher risk of partial necrosis in subzones III and IV.

TAA 1. The Role of Heparin in Endovascular Repair of Blunt Thoracic Aortic Injury

Early diagnosis and treatment are essential to improve survival of patients with blunt thoracic aortic injury (BTAI). Often, aortic surgical intervention may be delayed because of increased risk of bleeding with heparin, particularly in polytrauma victims. We believe that surgical delay may be remedied by proceeding without heparinization. This study reviewed the outcome of patients subjected to thoracic endovascular aortic repair (TEVAR) under full, low-dose, and no intraoperative systemic heparinization. There were 77 cases of confirmed BTAI identified and retrospectively analyzed at a high-volume urban trauma center during a period of 15 years (March 2003-September 2017). Patients were stratified into three groups on the basis of the intraoperative use of heparin during TEVAR as follows: full heparin (FH), low-dose heparin (LH), and no heparin (NH). Baseline characteristics including the patients' demographics, diagnostic laboratory data and imaging studies, operative reports, postoperative complications, embolic and bleeding outcomes, and mortality data were reviewed. Of the 77 total patients who underwent TEVAR for BTAI, 42 patients received FH, 18 received LH, and 17 had no use of systemic heparin. There was no significant difference in age, sex, body mass index, or smoking history. The most common mechanism of injury was motor vehicle collision. Grade 3 (pseudoaneurysm) was the predominant type of BTAI (FH, 69.0%; LH, 61.1%; NH, 76.5%; P = .23). The mean interval between admission and repair was three times longer in the FH group than in the NH group (FH, 2.33 days; NH, 0.76 day; P = .091). The mean time in the intensive care unit was shorter in the NH group vs the FH group (15 days vs 26.21 days; P = .025). Thromboembolic and bleeding outcomes and mortality rates were comparable in all three groups; 57 patients continued follow-up for a mean time of 30.99 months. Our study shows no statistically significant difference in outcomes between the heparinized and nonheparinized groups. The primary benefit of the NH group is seen in time to repair. Although not statistically significant, the mean time to repair was three times longer in the FH group. Patients in the NH group also benefited from prompt intervention and treatment. Therefore, intraoperative heparinization in critically ill patients with BTAI undergoing TEVAR remains at the surgeon's discretion, although the lack of heparinization appears to be a safe and potentially faster alternative, particularly in the polytrauma patient.

The role of heparin in endovascular repair of blunt thoracic aortic injury

ObjectiveEarly diagnosis and treatment are essential to improve survival of patients with blunt thoracic aortic injury (BTAI). Often, aortic surgical intervention may be delayed because of increased risk of bleeding with heparin, particularly in polytrauma victims. We believe that surgical delay may be remedied by proceeding without heparinization. This study reviewed the outcome of patients subjected to thoracic endovascular aortic repair (TEVAR) under full, low-dose, and no intraoperative systemic heparinization. MethodsThere were 77 cases of confirmed BTAI identified and retrospectively analyzed at a high-volume urban trauma center during a period of 15 years (March 2003-September 2017). Patients were stratified into three groups on the basis of the intraoperative use of heparin during TEVAR, as follows: full heparin (FH), low-dose heparin (LH), and no heparin (NH). Baseline characteristics including the patients' demographics, diagnostic laboratory data and imaging studies, operative reports, postoperative complications, embolic and bleeding outcomes, and mortality data were reviewed. ResultsOf the 77 total patients who underwent TEVAR for BTAI, 42 patients received full-dose heparinization, 18 received low-dose heparin, and 17 had no use of systemic heparin. There was no significant difference in age, sex, body mass index, or smoking history. The most common mechanism of injury was motor vehicle collision. Grade 3 (pseudoaneurysm) was the predominant type of BTAI (FH, 69.0%; LH, 61.1%; NH, 76.5%; P = .23). The mean interval between admission and repair was three times longer in the FH group than in the NH group (FH, 2.33 days; NH, 0.76 day; P = .091). The mean time in the intensive care unit was shorter in the NH group vs the FH group (15 days vs 26.21 days; P = .025). Thromboembolic and bleeding outcomes and mortality rates were comparable in all three groups; 57 patients continued follow-up for a mean time of 30.99 months. ConclusionsOur study shows no statistically significant difference in outcomes between the heparinized and nonheparinized groups. The primary benefit of the NH group is seen in time to repair. Although not statistically significant, the mean time to repair was three times longer in the FH group. Patients in the NH group also benefited from prompt intervention and treatment. Therefore, intraoperative heparinization in critically ill patients with BTAI undergoing TEVAR remains at the surgeon's discretion, although the lack of heparinization appears to be a safe and potentially faster alternative, particularly in the polytrauma patient.

Is Systemic Heparinization Necessary during Living Donor Hepatectomy?

Systemic heparinization has traditionally been performed during living donor hepatectomy (LDH) at most transplant centers because of the possibility of graft vascular thrombosis. However, no consensus on the use of systemic heparinization during LDH has yet emerged. The aims of the present study were to compare donor and recipient outcomes with reference to systemic heparinization and to determine whether or not systemic heparin needs to be administered to living donors. Via a retrospective review, we analyzed the outcomes of 175 LDHs performed at our institution from January 2011 to December 2014; 79 donors received systemic heparinization (group I), whereas 96 did not, but the liver graft was flushed with a heparinized perfusate (group II). The mean follow-up period was 60.6 ± 24.6 months for group I and 47.1 ± 13.5 months for group II. Patient demographics, intraoperative parameters, postoperative complications, and survival rates were compared between the two groups. The overall complication rates in donors did not differ significantly between the two groups, but postoperative bleeding requiring red blood cell transfusions in donors occurred more frequently in group I versus group II (7.6% versus 1.0%, P = 0.028). The incidences of graft vascular thrombosis were similar in the two groups, and no graft loss caused by vascular thrombosis was evident during the early postoperative period. The incidence of biliary stricture in recipients was not higher in donors who did not receive systemic heparin (5.1% versus 8.3%, P = 0.394). Moreover, the 1-,3-,and 5-year graft survival rates in the group I and group II were 87.1%, 84.5%, 81.9% and 96.9%, 94.7%, 93.6%, respectively and so overall graft survival in group II was higher than that in group I (p=0.018). In conclusion, the omission of systemic heparinization during LDH is both feasible and safe, with no adverse effects on donor or recipient outcomes.

Abstract 18794: Systemic Heparin Use and Outcomes in Cardiac Arrest Patients Treated With Therapeutic Hypothermia Without Coronary Intervention

Introduction: The effects of hypothermia on hemostatic function are complex and poorly understood. While cardiac arrest and CPR can elicit a pro-inflammatory, pro-coagulant state, hypothermia may alter platelet count, activation and aggregation. Hypothesis: We hypothesized that treatment with systemic heparin during therapeutic hypothermia (TH) is associated with improved neurologic outcomes. Methods: We conducted a retrospective study of 157 cardiac arrest survivors treated with TH at our institution from 2007-2014. A priori, we excluded TH patients (pts) presenting with an acute coronary syndrome requiring percutaneous coronary intervention, pulmonary embolus, venous thrombosis or need for mechanical circulatory support. We used a multivariable logistic regression model to examine the relationship between systemic heparin and neurologic outcome (Cerebral Performance Category score 1-2=good; 3-5=poor) as well as inpatient survival. We also performed a chi-square analysis for the secondary endpoint of major bleeding. Results: Mean age was 57.0 (+/- 16.2) years; 86 (54%) pts were male; and 75 (47.8%) pts had an initial rhythm of ventricular tachycardia or ventricular fibrillation. At discharge, 48 (30.6%) pts had a good neurologic outcome and 23 (14.7%) pts suffered from a major bleed. Systemic heparin was administered to 48 (30.6%) pts, and was neither associated with favorable neurologic outcome (OR 0.99, CI 0.39-2.56, p=0.991) nor inpatient survival (OR 1.28, CI 0.54-3.05, p=0.574). The risk of bleeding with heparin was 2.08 (CI 0.99-4.38, p=0.052). Conclusions: In our cohort, indiscriminate use of systemic heparin during TH post-cardiac arrest was not associated with improved neurologic outcomes. Conversely, a trend towards increased risk of major bleeding was noted.

Effect of Intra Operative Intravenous Injection of Heparin on Patency Rate of Radio Cephalic Autogenous Arteriovenous-Fistula in Chronic Renal Failure Patients

Background: Currently, there is no standard for the use of systemic heparin during creation of Arteriovenous (AV) fistula to decrease the incidence of postoperative thrombotic complications. Objectives: The goal of this study was to evaluate the effects of intra-operative IV heparin on patency rate and postoperative bleeding complications in patients undergoing surgery for AV fistula. Patients and Methods: A prospective, randomized controlled study was performed on 50 patients undergoing AV fistula creation, who were randomly divided in two groups. The control group received no systemic heparin and the heparin group received 5,000 units of intravenous heparin before clamping of theartery. Results: There was a significant difference in patency rate between the heparin and control groups (96% vs. 72%, P = 0.021), and there were no significant differences in operative time (P = 0.55). Perioperative bleeding was not significantly different between the two groups. Conclusions: The results suggest that intra operative administration of heparin has statistically significant effects on patency rates yet not on postoperative bleeding complications. Larger trials with longer follow-up durations and assessment of maturation rates are needed to determine this effect on fistula outcome.

Is Systemic heparinization necessary during living donor hepatectomy?

Systemic heparinization has traditionally been performed during living donor hepatectomy (LDH) at most transplant centers because of the possibility of graft vascular thrombosis. However, no consensus on the use of systemic heparinization during LDH has yet emerged. The aims of the present study were to compare donor and recipient outcomes with reference to systemic heparinization and to determine whether or not systemic heparin needs to be administered to living donors. Via a retrospective review, we analyzed the outcomes of 137 LDHs performed at our institution from January 2011 to October 2013; 79 donors received systemic heparinization (group I), whereas 58 did not, but the liver graft was flushed with a heparinized perfusate (group II). Patient demographics, intraoperative parameters, laboratory data, postoperative complications, and survival rates were compared between the 2 groups. The overall complication rates did not differ significantly between the 2 groups, but postoperative bleeding requiring red blood cell transfusions occurred more frequently in group I versus group II (7.6% versus 0.0%, P = 0.03). The incidences of graft vascular thrombosis were similar in the 2 groups, and no graft loss caused by vascular thrombosis was evident during the early postoperative period. Moreover, no difference in either posttransplant graft function or survival was apparent between the 2 groups. The rates of decreases in donor hemoglobin, hematocrit, and platelet count levels during the early postoperative period were significantly higher in group I versus group II. In conclusion, the omission of systemic heparinization during LDH is both feasible and safe, with no adverse effects on donor or recipient outcomes.

The use of heparin in patients with ruptured abdominal aortic aneurysms

The use of systemic heparin in patients with ruptured abdominal aortic aneurysms (rAAAs) remains a contentious issue with no clear guidelines. This review reports the current understanding, at a molecular and clinical level, of the possible benefits and risks of heparin in emergency aneurysm repair (both open and endovascular). MEDLINE, EMBASE, AMED, SCOPUS, CINAHL and Cochrane Library were searched for all articles containing the keywords 'rupture', 'abdominal', 'aneurysm' and 'heparin'. Current experience, indications and outcomes were analyzed. Articles were searched for both endovascular and open repair of AAAs. A total of eight studies were included for analysis in the systematic review. Of these, only one paper focused specifically on heparin use in open repair of ruptures and suggested a benefit. Of the remaining seven, two were self-reporting retrospective studies assessing individual surgeons' practice, one was a case report and the remaining four included mention of heparin use but with no outcome data. The evidence available suggests that a pro-coagulable state exists in rAAAs. This may be responsible for the morbidity and mortality postprocedure, which arises predominantly from multiple organ failure and cardiac compromise rather than outright hemorrhage. This diathesis may respond well to heparin administration, suggesting that heparin administration in ruptured aneurysms is appropriate.

A Prospective Clinical Evaluation of the Effects of Intraoperative Systemic Anticoagulation in Patients Undergoing Arteriovenous Fistula Surgery

No standard presently exists for the use of systemic heparin during angioaccess surgery to decrease the incidence of postoperative thrombotic complications. Our objective was to study the effects of intraoperatively administered heparin on 30-day patency and postoperative bleeding complications in patients undergoing autogenous arteriovenous (AV) fistula surgery. A prospective, double-blinded, randomized controlled study was performed on 48 patients undergoing AV fistula creation from April 2007 through November 2009. Of the 48 patients, 22 were randomized to the control group and received no heparin. Twenty-six were randomized to receive heparin (75 units/kg intravenously) before clamping of the artery. There was no significant difference in 30-day patency between the heparin and control groups (92% vs. 86%, P = 0.65), respectively. Three patients (12%) developed hematomas in the heparin group compared with one (5%) in the control group; however the difference was not statistically significant (P = 0.61). The results suggest that intraoperative administration of heparin has no statistically significant effect on 30-day patency rates or postoperative bleeding complications. Larger trials with longer term follow-up and assessment of maturation rates are needed to determine the effect of intraoperative anticoagulation on these outcomes of arteriovenous fistula surgery.

Heparin versus citrate for anticoagulation in critically ill patients treated with continuous renal replacement therapy

Continuous renal replacement therapy (CRRT) is commonly used in the care of critically ill patients (Gabutti et al., 2002). Critical illness increases the likelihood to both coagulation and bleeding, making anticoagulation for CRRT problematic. This mini-review aims to examine the evidence that compares the use of systemic heparin and regional citrate as forms of anticoagulation for CRRT in critically ill patients. The primary outcome of interest was haemofilter circuit survival, and the secondary outcome was reduced risk of bleeding. A systematic literature search was undertaken to identify all studies comparing these drugs. The Cochrane Library, Medline and Embase databases were searched. Eighty-nine articles were found. Included studies were randomized controlled trials (RCTs), which used a target population of critically ill adults. Studies were excluded if they had not been written in English and if they were not available through King's College London. After applying the inclusion and exclusion criteria, three RCTs comparing the use of systemic heparin and regional citrate were included in the review. Two studies showed significant differences in circuit survival time, with citrate prolonging survival time. All studies showed an increased risk of bleeding in the heparin group, resulting in a higher rate of transfusion while heparin was being used. The studies examined lacked reference to the power of the studies and strength in the presentation of the results. Because of the lack of reliability in the studies, it would be suggested that further research is needed on this topic in order to produce rigorous high-quality reviews with limited bias. The use of citrate, as with all treatments in clinical practice, should be used with caution and assessed on an individual patient basis. Reviewing this evidence helps to gain an insight into different treatment options available, identifying some of the risks and benefits.

Autologous blood collection in abdominal vascular surgery. Assessment of a low pressure blood salvage system with particular reference to the preservation of cellular elements, triglyceride, complement and bacterial content in the collected blood.

A simple, low pressure, blood scavenging system has been assessed in major abdominal vascular operations. The aim of this study was to assess the quality of blood obtained with this device and its suitability for reinfusion. Three areas of special interest, which have not been reported so far, are the fate of plasma complement, the load of fat aspirated after tissue dissection and the degree of bacterial contamination in the scavenged blood. The development of autologous blood scavenging systems is reviewed. The features which most affect the quality of scavenged blood are identified and their importance discussed by comparison with our experience. Key features of our system were: simplicity of the apparatus, controlled low-pressure aspiration, the use of systemic heparin and the avoidance of mechanical pumps. The blood obtained was of excellent quality with good preservation of cellular elements, platelets and fibrinogen. Plasma total haemolytic complement, C3 and C4 fractions were preserved in normal, though slightly reduced, quantities. Lipid (triglyceride) content was minimally increased after filtration. Bacterial contamination was present in all cases, but at a very low level provided that aspiration was limited to the peritoneal cavity. This low-level of contamination is not thought to be of great significance; its origin and importance are discussed.

Is Systemic Heparin a Risk Factor for Catheter-Related Sepsis in Dialysis Patients?

Background: Biofilms are dense aggregates of surface adherent microorganisms embedded in a polysaccharide matrix. Intravenous iron and heparin are thought to promote the formation of biofilm. Both are commonly employed during hemodialysis treatments which might affect the incidence of catheter-related sepsis. Methods: 559 patients who underwent hemodialysis treatment with a catheter were reviewed. Episodes of sepsis were analyzed for the use of systemic heparin and intravenous iron as well as all other risk factors for sepsis. Results: Sepsis developed in 141 of the 796 catheters. Analysis of variance revealed that the number of days that the catheter remained in place was the most significant variable (p < 0.0001) associated with catheter-related sepsis along with multiple other variables, but a Cox proportional hazards analysis revealed that only the two biofilm risk factors (intravenous iron [p < 0.001], and mid-treatment bolus of heparin [p = 0.046]) along with previously reported factor of a depressed serum albumin (p = 0.001) are of significance. Conclusion: In addition to duration of catheter use, we found three significant risk factors for sepsis and two of those three have been associated with the development of biofilm.

Off-Pump Open Pulmonary Embolectomy for Patients with Major Pulmonary Embolism

Acute major pulmonary artery embolism (AMPE) requires rapid diagnosis and early intensive treatment to optimize patient outcomes. Most patients with AMPE and hemodynamic instability need open pulmonary embolectomy (OPE). We modified the technique of OPE to include a minimally invasive procedure without the use of cardiopulmonary bypass (CPB). From March 1988 to April 2006, we performed OPE on a total of 12 patients (21 sides) with AMPE. Seven patients (13 sides) underwent conventional OPE with CPB and 5 patients underwent off-pump OPE (OPPE), 4 (8 sides) with AMPE and 1 with catheter embolus with thrombosis. In patients who underwent conventional OPE, there was 1 hospital death in a patient with severe right ventricle dysfunction and 2 significant cases of airway bleeding. In patients who underwent OPPE, there was 1 case of minimal airway bleeding. Mean systolic pulmonary artery pressure in conventional OPE and OPPE patients, respectively, decreased from 50.3 +/- 14 mmHg and 35.4 +/- 6.6 mmHg pre-operatively to 41.7 +/- 20 and 28 +/- 3 mmHg postoperatively. During the long-term follow-up, there were 2 cancer-related deaths but no recurrence of PE. All surviving patients maintained functional class I (n = 10) or II (n = 1). Compared with conventional OPE, OPPE was effective for treating AMPE in our selected cases. Modification of conventional CPB and systemic full heparinization to minimal use of systemic heparinization without CPB may be helpful in treating selected patients with AMPE.

ECMO – Long term follow-up

Since ECMO was first introduced in the late 1970s for the treatment of acute hypoxic respiratory failure (AHRF) in children, it has been used in over 25,000 patients worldwide. Data from the Extracorporeal Life Support Organization (ELSO) shows that ECMO has been used in over 20,000 neonates with an overall survival of 80%. Despite this impressive record, less is known about the long term morbidity associated with what is the ultimate means of technological support. In neonatal respiratory failure, the main area of concern is neurological morbidity which is likely to be multifactorial in aetiology. Factors that may influencethis morbidity are the degree of hypoxaemia prior to cannulation, the use of hyperventilation to treat PPHN, the cannulation and ligation of the carotid artery and the internal jugular vein, the use of systemic heparinization in the near-term or pre-term infant and the duration of ECMO support. Outside of the central nervous system, major factors that determine long term pulmonary morbidity are pre-existing pulmonary morbidity (BPD) and the pulmonary vascular disease and pulmonary hypoplasia that is seen in congenital diaphragmatic hernia. This latter category of patient seems to be particularly problematic, firstly because the overall survivor rate is lower than other forms of neonatal respiratory failure (60% survival vs. 80% survival) and the incidence of significant neurological disability also seems higher. A recent retrorospective review from ECMO centres in the United Kingdom showed that in 73 patients with CDH treated with ECMO there were 27 survivors to one year of age, but 13 of these had long term respiratory morbidity, while 7 had neurodevelopmental problems. However, when evaluating data like this, one has to try and separate the morbidity associated with the use of ECMO versus the morbidity inherent with acute hypoxic respiratory failure in the newborn. The best data that we have in order to help separate these two issues is the long term outcome from the UK randomised controlled trial of neonatal ECMO. The end point for this study wasoutcome at one yearof age and subsequent evaluation. Patients randomized to receive ECMO had better overall outcomes at the one year mark and the four year survival data was published in the Lancet in 2004. This showed that 50% of the ECMO long term survivors had no disability while only 37% of those treated in the conventional arm were normal (Table 1). This landmark study has established the superiority of ECMO over conventional therapy for infants with severe AHRF. With further technological advances such as the use of heparin bonded circuits, repair of the neck vessels at the time of decannulation and the decreased use of hyperventilation to treat PPHN, there is an expectation that this neurological morbidity will fall substantially in the future. Long term outcome in older children with AHRF is

Surgical results of low-dose systemic heparinization (1 mg/kg, 100 IU/kg) in thoracic aortic operation combined with a heparin-coated cardiopulmonary bypass circuit: Is low-dose heparinization safe during deep hypothermic circulatory arrest?

Heparin-coated cardiopulmonary bypass circuits allow a reduction in the use of systemic heparin administered during cardiopulmonary bypass. This study was carried out to investigate safety during deep hypothermic circulatory arrest in this low-dose heparin group during thoracic aortic operation. Heparin-coated cardiopulmonary bypass circuits were used in 30 adult patients who underwent thoracic aortic operations that required deep hypothermic circulatory arrest. The patients were divided into two groups. Six patients received 300 IU/kg of heparin, and the remaining 24 patients received 100 IU/kg. Clinical outcomes (mortality, incidence of stroke, and transfusion volumes during operation) were examined. All devices remained functional throughout the procedures, and no systemic emboli were detected. Two deaths occurred in the high-dose heparin group, but no deaths occurred in the low-dose heparin group (P = 0.03). The percentage of patients requiring transfusion was similar in the two groups (66.7% vs. 70.8%), but the median exposure to allogenic blood products was greater in the high-dose heparin group than in the low-dose heparin group (9.8 ± 9.5 units vs. 5.5 ± 5.2 units; P = 0.09). Reduced systemic heparinization, combined with hepar-in-coated cardiopulmonary bypass circuits during deep hypothermic circulatory arrest, can be performed with acceptably low early mortality in thoracic aortic operations. Patients are not at increased risk for stroke.