In Vitro Treatment of Extracorporeal Membrane Oxygenation Coagulopathy with Recombinant von Willebrand Factor or Lyophilized Platelets

OBJECTIVES

The objective was to compare primary hemostasis between adult ECMO patients and cardiac surgical patients before heparinization and cardiopulmonary bypass. Furthermore, the authors explored whether in vitro treatment of ECMO patient blood samples with recombinant von Willebrand Factor (vWF) or lyophilized platelets improved primary hemostasis in vitro.

DESIGN

Prospective cohort study.

SETTING

Single academic medical center.

PARTICIPANTS

Ten cardiac surgical patients and 8 adult ECMO patients.

INTERVENTIONS

Cardiac surgical patients and ECMO patients had blood samples collected, and in vitro platelet thrombus formation was assessed using the ATLAS PST device. The ECMO patients had platelet thrombus formation evaluated at baseline and after in vitro treatment with recombinant vWF or lyophilized platelets, whereas cardiac surgical patients had a single blood sample obtained before heparinization and cardiopulmonary bypass run.

MEASUREMENTS AND MAIN RESULTS

Median maximum force (39.7 v 260.2 nN) and thrombus area (0.05 v 0.11) at 5 minutes were lower in untreated ECMO patient samples compared with cardiac surgical patients (p = 0.008 and p < 0.001, respectively). The ECMO patient samples treated with recombinant vWF demonstrated an increase in both platelet maximum force (median value of 222.1 v 39.7 nN) (p = 0.01) and platelet thrombus area (median value of 0.16 v 0.05; p = 0.001). The ECMO patient samples treated with lyophilized platelets demonstrated no increase in platelet maximum force (median value of 193.3 v 39.7 nN; p = 0.18); however, there was a significant increase in platelet thrombus area (median value of 0.13 v 0.05; p = 0.04).

CONCLUSIONS

Recombinant vWF and lyophilized platelets may help to restore primary hemostasis in ECMO patients. Future studies should further evaluate the safety and efficacy of these potential therapeutics in ECMO patients.

Complications of Vascular Disease

Vascular diseases and their sequelae increase perioperative risk for noncardiac surgical patients. In this review, the authors discuss vascular diseases, their epidemiology and pathophysiology, risk stratification, and management strategies to reduce adverse perioperative outcomes.

Racial-ethnic disparities in potentially preventable complications after cesarean delivery in Maryland: an observational cohort study

Background

Potentially preventable complications are monitored as part of the Maryland Hospital Acquired Conditions Program and are used to adjust hospital reimbursement. Few studies have evaluated racial-ethnic disparities in potentially preventable complications.

Our study objective was to explore whether racial-ethnic disparities in potentially preventable complications after Cesarean delivery exist in Maryland.

Methods

We performed a retrospective observational cohort study using data from the Maryland Health Services Cost Review Commission database. All patients having Cesarean delivery, who had race-ethnicity data between fiscal years 2016 and 2020 were included. Multivariable logistic regression modeling was performed to estimate risk-adjusted odds of having a potentially preventable complication in patients of different race-ethnicity.

Results

There were 101,608 patients who had Cesarean delivery in 33 hospitals during the study period and met study inclusion criteria. Among them, 1,772 patients (1.7%), experienced at least one potentially preventable complication. Patients who had a potentially preventable complication were older, had higher admission severity of illness, and had more government insurance. They also had more chronic hypertension and pre-eclampsia (both P<0.001). Median length of hospital stay was longer in patients who had a potentially preventable complications (4 days vs. 3 days, P<0.001) and median hospital charges were approximately $4,600 dollars higher, (P<0.001). The odds of having a potential preventable complication differed significantly by race-ethnicity group (P=0.05). Hispanic patients and Non-Hispanic Black patients had higher risk-adjusted odds of having a potentially preventable complication compared to Non-Hispanic White patients, OR=1.26 (95% CI=1.05 to 1.52) and OR=1.17 (95% CI=1.03 to 1.33) respectively.

Conclusions

In Maryland a small percentage of patients undergoing Cesarean delivery experienced a potentially preventable complication with Hispanic and Non-Hispanic Black patients disproportionately impacted. Continued efforts are needed to reduce potentially preventable complications and obstetric disparities in Maryland.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-022-04818-5.

Overt Disseminated Intravascular Coagulation with Severe Hypofibrinogenemia During Veno-Venous Extracorporeal Membrane Oxygenation

Disseminated intravascular coagulation (DIC) is a life-threatening hematologic derangement characterized by dysregulated thrombin generation and excessive fibrinolysis. However, DIC is poorly characterized in the extracorporeal membrane oxygenation (ECMO) population, and the underlying mechanisms are not well understood. Several mechanisms contribute to DIC in ECMO, including consumption of coagulation factors, acquired von Willebrand's syndrome leading to thrombocytopenia, and hyperfibrinolysis. There are few case reports of DIC in adult ECMO patients. Most are in the context of venoarterial ECMO, which is typically used in the setting of cardiogenic shock and cardiac arrest. These disease states themselves are known to be associated with DIC, liver failure, impaired anticoagulant mechanisms, and increased fibrinolysis. We present an unusual case of a 74-year-old man who developed overt DIC during veno-venous (VV) ECMO. DIC resulted in clinical bleeding and severe hypofibrinogenemia requiring massive cryoprecipitate transfusion of 87 pooled units. When the patient was decannulated from ECMO, his platelet count and fibrinogen concentration improved within 24 hours, suggesting that ECMO was a proximate cause of his DIC.

The Year in Extracorporeal Membrane Oxygenation: Selected Highlights From 2021

This review summarizes the extracorporeal membrane oxygenation (ECMO) or extracorporeal life support literature published in 2021. This Selected Highlights article is not intended to be an exhaustive review of the literature, but rather a summarizing of key themes that developed in the ECMO literature during 2021. The primary topics presented include the following: ECMO for coronavirus disease 2019, extracorporeal cardiopulmonary resuscitation, periprocedural cardiopulmonary support with ECMO, and anticoagulation for ECMO.

In Vitro Comparison of Recombinant and Plasma-Derived von Willebrand Factor Concentrate for Treatment of Acquired von Willebrand Syndrome in Adult Extracorporeal Membrane Oxygenation Patients

BACKGROUND

Coagulopathic bleeding is common during adult extracorporeal membrane oxygenation (ECMO), and acquired von Willebrand syndrome is a contributing factor. We compared ECMO patient blood samples that were treated in vitro with recombinant von Willebrand Factor concentrate and plasma-derived von Willebrand Factor concentrate. Our hypothesis was that recombinant von Willebrand Factor (vWF) would have greater efficacy in increasing vWF function. Secondarily, we hypothesized that recombinant vWF would have less impact on thrombin generation.

METHODS

Thirty ECMO patients and 10 cardiac surgical controls were enrolled in the study. ECMO patient blood samples were treated in vitro with low- and high-dose recombinant vWFs and low- and high-dose plasma-derived vWFs. Whole blood ristocetin-induced platelet aggregation (RIPA), plasma ristocetin cofactor activity (RCo), and thrombin generation were compared between ECMO patient blood samples and control blood samples and between vWF-treated ECMO patient blood samples and nontreated samples.

RESULTS

ECMO patient blood samples had severely reduced median RIPA compared to control samples 2 ohms (1-12 [25th-75th percentile]) vs 20 ohms (11-42) (P < .001). Treatment of ECMO patient blood samples with high-dose recombinant vWF significantly increased median RIPA to 10 ohms (2-15) (P < .001), while low-dose recombinant vWF and low- and high-dose plasma-derived vWFs did not significantly increase RIPA; 6 ohms (3-14), 4 ohms (1-13), and 6 ohms (2-10), respectively (P = .25, >.99, and >.99). Treatment with high-dose recombinant vWF and low- and high-dose plasma-derived vWFs significantly increased median plasma RCo to 4.7 international units (IU)/mL (3.7-5.9), 3.3 IU/mL (2.7-4.8), and 3.9 IU/mL (3.4-5.3), respectively, compared to controls 1.8 IU/mL (1.5-2.3) (all P < .001). Treatment with low- and high-dose plasma-derived vWFs significantly increased mean endogenous thrombin potential (6270.2 ± 2038.7 and 6313.1 ± 1913.3) compared to nontreated samples (5856.7 ± 1924.6) (P = .04 and .006), whereas treatment with low- and high-dose recombinant vWFs had no significant effect on mean endogenous thrombin potential (5776.1 ± 2087.3 and 5856.2 ± 1946.4) (P > .99 for both comparisons).

CONCLUSIONS

In vitro treatment of ECMO patient blood samples with high-dose recombinant vWF was superior to low-dose recombinant vWF and plasma-derived vWF in terms of improving RIPA. In addition, recombinant vWF treatment did not increase endogenous thrombin potential, which may reduce overall thrombotic risk if it used to treat acquired von Willebrand syndrome in ECMO patients.

Hispanic/Latino-Serving Hospitals Provide Less Targeted Temperature Management Following Out-of-Hospital Cardiac Arrest

Background Variation exists in outcomes following out-of-hospital cardiac arrest, but whether racial and ethnic disparities exist in postarrest provision of targeted temperature management (TTM) is unknown. Methods and Results We performed a retrospective analysis of a prospectively collected cohort of patients who survived to admission following out-of-hospital cardiac arrest from the Cardiac Arrest Registry to Enhance Survival, whose catchment area represents ≈50% of the United States from 2013 to 2019. Our primary exposure was race or ethnicity and primary outcome was utilization of TTM. We built a mixed-effects model with both state of arrest and admitting hospital modeled as random intercepts to account for clustering. Among 96 695 patients (24.6% Black patients, 8.0% Hispanic/Latino patients, and 63.4% White patients), a smaller percentage of Hispanic/Latino patients received TTM than Black or White patients (37.5% versus 45.0% versus 43.3%, P<0.001) following out-of-hospital cardiac arrest. In the mixed-effects model, Black patients (odds ratio [OR], 1.153 [95% CI, 1.102-1.207], P<0.001) and Hispanic/Latino patients (OR, 1.086 [95% CI, 1.017-1.159], P<0.001) were slightly more likely to receive TTM compared with White patients, perhaps because of worse neurological status on admission. We did find community- level disparity because Hispanic/Latino-serving hospitals (defined as the top decile of hospitals that cared for the highest proportion of Hispanic/Latino patients) provided less TTM (OR, 0.587 [95% CI, 0.474-0.742], P<0.001). Conclusions Reassuringly, we did not find evidence of intrahospital or interpersonal racial or ethnic disparity in the provision of TTM. However, we did find interhospital, community-level disparity. Hispanic/Latino-serving hospitals provided less guideline-recommended TTM after out-of-hospital cardiac arrest.

Women receive less targeted temperature management than men following out-of-hospital cardiac arrest due to early care limitations - A study from the CARES Investigators

BACKGROUND

Women experience worse neurological outcomes following out-of-hospital cardiac arrest (OHCA). It is unknown whether sex disparities exist in the use of targeted temperature management (TTM), a standard of care treatment to improve neurological outcomes.

METHODS

We performed a retrospective study of prospectively collected patients who survived to hospital admission following OHCA from the Cardiac Arrest Registry to Enhance Survival from 2013 through 2019. We compared receipt of TTM by sex in a mixed-effects model adjusted for patient, arrest, neighborhood, and hospital factors, with the admitting hospital modeled as a random intercept.

RESULTS

Among 123,419 patients, women had lower rates of shockable rhythms (24.4 % vs. 39.2%, P < .001) and lower rates of presumed cardiac aetiologies for arrest (74.3% vs. 81.1%, P < .001). Despite receiving a similar rate of TTM in the field (12.1% vs. 12.6%, P = .02), women received less TTM than men upon admission to the hospital (41.6% vs. 46.4%, P < .001). In an adjusted mixed-effects model, women were less likely than men to receive TTM (Odds Ratio 0.91, 95% Confidence Interval 0.89 to 0.94). Among the 27,729 patients with data indicating the reason for not using TTM, a higher percentage of women did not receive TTM due to Do-Not-Resuscitate orders/family requests (15.1% vs. 11.4%, p < .001) and non-shockable rhythms (11.1% vs. 8.4%, p < .001).

CONCLUSIONS

We found that women received less TTM than men, likely due to early care limitations and a preponderance of non-shockable rhythms.

Outcomes of cesarean delivery in obstetric patients with SARS-CoV-2 infection

SARS‐CoV‐2 infection was not associated with increased mortality, but was associated with a modest increase in morbidity, including stillbirth, in cesarean delivery patients in Maryland, USA.

Peripheral cannulation for extracorporeal membrane oxygenation yields superior neurologic outcomes in adult patients who experienced cardiac arrest following cardiac surgery

BACKGROUND

Extracorporeal cardiopulmonary resuscitation (ECPR) for refractory cardiac arrest has improved mortality in post-cardiac surgery patients; however, loss of neurologic function remains one of the main and devastating complications. We reviewed our experience with ECPR and investigated the effect of cannulation strategy on neurologic outcome in adult patients who experienced cardiac arrest following cardiac surgery that was managed with ECPR.

METHODS

Patients were categorized by central versus percutaneous peripheral VA-extracorporeal membrane oxygenation (ECMO) cannulation strategy. We reviewed patient records and evaluated in-hospital mortality, cause of death, and neurologic status 72 hours after cannulation.

RESULTS

From January 2010 to September 2019, 44 patients underwent post-cardiac surgery ECPR for cardiac arrest. Twenty-six patients received central cannulation; 18 patients received peripheral cannulation. Mean post-operative day of the cardiac arrest was 3 and 9 days (p = 0.006), and mean time between initiation of CPR and ECMO was 40 ± 24 and 28 ± 22 minutes for central and peripheral cannulation, respectively. After 72 hours of VA-ECMO support, 30% of centrally cannulated patients versus 72% of peripherally cannulated patients attained cerebral performance status 1-2 (p = 0.01). Anoxic brain injury was the cause of death in 26.9% of centrally cannulated and 11.1% of peripherally cannulated patients. Survival to discharge was 31% and 39% for central and peripheral cannulation, respectively.

CONCLUSIONS

Peripheral VA-ECMO allows for continuous CPR and systemic perfusion while obtaining vascular access. Compared to central cannulation, a peripheral cannulation strategy is associated with improved neurologic outcomes and decreased likelihood of anoxic brain death.

Neurological complications during veno-venous extracorporeal membrane oxygenation: Does the configuration matter? A retrospective analysis of the ELSO database

Background

Single- (SL) and double-lumen (DL) catheters are used in clinical practice for veno-venous extracorporeal membrane oxygenation (V-V ECMO) therapy. However, information is lacking regarding the effects of the cannulation on neurological complications.

Methods

A retrospective observational study based on data from the Extracorporeal Life Support Organization (ELSO) registry. All adult patients included in the ELSO registry from 2011 to 2018 submitted to a single run of V-V ECMO were analyzed. Propensity score (PS) inverse probability of treatment weighting estimation for multiple treatments was used. The average treatment effect (ATE) was chosen as the causal effect estimate of outcome. The aim of the study was to evaluate differences in the occurrence and the type of neurological complications in adult patients undergoing V-V ECMO when treated with SL or DL cannulas.

Results

From a population of 6834 patients, the weighted propensity score matching included 6245 patients (i.e., 91% of the total cohort; 4175 with SL and 20,270 with DL cannulation). The proportion of patients with at least one neurological complication was similar in the SL (306, 7.2%) and DL (189, 7.7%; odds ratio 1.10 [95% confidence intervals 0.91–1.32]; p = 0.33). After weighted propensity score, the ATE for the occurrence of least one neurological complication was 0.005 (95% CI − 0.009 to 0.018; p = 0.50). Also, the occurrence of specific neurological complications, including intracerebral hemorrhage, acute ischemic stroke, seizures or brain death, was similar between groups. Overall mortality was similar between patients with neurological complications in the two groups.

Conclusions

In this large registry, the occurrence of neurological complications was not related to the type of cannulation in patients undergoing V-V ECMO.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-021-03533-5.

Tissue Factor Pathway Inhibitor Levels During Veno-Arterial Extracorporeal Membrane Oxygenation in Adults

Tissue factor pathway inhibitor (TFPI) has multiple anticoagulant properties. To our knowledge, no studies have measured TFPI levels in adult veno-arterial (VA) extracorporeal membrane oxygenation patients. We hypothesized that adult VA ECMO patients would have increased TFPI levels and slowed tissue factor triggered thrombin generation. Twenty VA ECMO patients had TFPI levels and thrombin generation lag time measured on ECMO day 1 or 2, day 3, and day 5. TFPI levels and thrombin generation lag time were compared against healthy control plasma samples. Mean TFPI levels were significantly higher in ECMO patients on ECMO day 1 or 2 = 81,877 ± 19,481 pg/mL, day 3 = 73,907 ± 26,690 pg/mL, and day 5 = 77,812 ± 23,484 pg/mL compared with control plasma = 38,958 ± 9,225 pg/mL (P < 0.001 for all comparisons). Median thrombin generation lag time was significantly longer in ECMO patients on ECMO day 1 or 2 = 10.0 minutes [7.5, 13.8], day 3 = 9.0 minutes [6.8, 12.1], and day 5 = 10.7 minutes [8.3, 15.2] compared with control plasma = 3.6 minutes [2.9, 4.2] (P < 0.001 for all comparisons). TFPI is increased in VA ECMO patients and tissue factor triggered thrombin generation is slowed. Increased TFPI levels could contribute to the multifactorial coagulopathy that occurs during ECMO.

Clinical Practice Variation and Outcomes for Stanford Type A Aortic Dissection Repair Surgery in Maryland: Report from a Statewide Quality Initiative

Background  Stanford Type A aortic dissection repair surgery is associated with high mortality and clinical practice remains variable among hospitals. Few studies have examined statewide practice variation.

Methods  Patients who had Stanford Type A aortic dissection repair surgery in Maryland between July 1, 2014 and June 30, 2018 were identified using the Maryland Cardiac Surgery Quality Initiative (MCSQI) database. Patient demographics, comorbidities, surgery details, and outcomes were compared between hospitals. We also explored the impact of arterial cannulation site and brain protection technique on outcome.

Results  A total of 233 patients were included from eight hospitals during the study period. Seventy-six percent of surgeries were done in two high-volume hospitals (≥10 cases per year), while the remaining 24% were done in low-volume hospitals. Operative mortality was 12.0% and varied between 0 and 25.0% depending on the hospital. Variables that differed significantly between hospitals included patient age, the percentage of patients in shock, left ventricular ejection fraction, creatinine level, arterial cannulation site, brain protection technique, tobacco use, and intraoperative blood transfusion. The percentage of patients who underwent aortic valve repair or replacement procedures differed significantly between hospitals ( p  < 0.001), although the prevalence of moderate-to-severe aortic insufficiency was not significantly different ( p  = 0.14). There were no significant differences in clinical outcomes including mortality, renal failure, stroke, or gastrointestinal complications between hospitals or based on arterial cannulation site (all p  > 0.05). Patients who had aortic cross-clamping or endovascualr repair had more embolic strokes when compared with patients who had hypothermic circulatory arrest ( p  = 0.03).

Conclusion  There remains considerable practice variation in Stanford Type A aortic dissection repair surgery within Maryland including some modifiable factors such as intraoperative blood transfusion, arterial cannulation site, and brain protection technique. Continued efforts are needed within MCSQI and nationally to evaluate and employ the best practices for patients having acute aortic dissection repair surgery.

Platelet factor-4 concentration in adult veno-arterial ECMO patients

BACKGROUND

Heparin induced thrombocytopenia (HIT) is reported at a variable rate in extracorporeal membrane oxygenation (ECMO) patients. A critical factor impacting platelet factor-4 (PF4)-heparin antibody formation is plasma PF4 concentration. We hypothesized that PF4 concentration would be increased during veno-arterial (VA) ECMO.

METHODS

Plasma PF4 concentration was measured during the first 5 ECMO days in 20 VA ECMO patients and 10 control plasma samples. PF4-heparin ratios were estimated using an assumed heparin concentration of 0.4 IU/mL. This correlates with an activated partial thromboplastin time of 60 to 80 seconds, which is the anticoagulation target in our center.

RESULTS

Twenty VA ECMO patients were enrolled, 10 of which had pulmonary embolism. Median PF4 concentration was 0.03 µg/mL [0.01, 0.13] in control plasma. Median PF4 concentration was 0.21 µg/mL [0.12, 0.34] on ECMO day 1 or 2, 0.16 µg/mL [0.09, 0.25] on ECMO day 3, and 0.12 µg/mL [0.09, 0.22] on ECMO day 5. Estimated median PF4-heparin ratios were 0.04, 0.03, and 0.02 respectively. Two patients (10%) developed HIT that was confirmed by serotonin release assay. PF4 concentration did not differ significantly in these patients compared to non-HIT patients (p = 0.37). No patient had an estimated PF4-heparin ratio between 0.7 and 1.4, which is the reported optimal range for PF4-heparin antibody formation.

CONCLUSION

Our data suggest that PF4 concentration is mildly elevated during VA ECMO compared to control plasma. Estimated PF4-heparin ratios were not optimal for HIT antibody formation. These data support epidemiologic studies where HIT incidence is low during VA ECMO.

Anemia, sex, and race as predictors of morbidity or mortality after knee arthroplasty surgery

BACKGROUND

Anemia is associated with poor outcome after major joint replacement surgery, but it is unclear whether sex and race modify its impact on outcome. We hypothesized that anemia would be associated with increased morbidity or mortality after knee arthroplasty surgery and that sex and race would be effect modifiers for this relationship.

STUDY DESIGN AND METHODS

We performed a retrospective cohort study of elective knee arthroplasty patients between 2013 and 2018 using data from the National Surgical Quality Improvement Program. Morbidity or mortality after surgery was compared between patients without anemia, with mild anemia, and with moderate to severe anemia. Multivariable logistic regression was used to determine adjusted odds for morbidity or mortality with anemia. Interaction terms were entered into the model to test for effect modification by sex and race.

RESULTS

243 491 patients were included and 30 135 patients (12.4%) were anemic. Morbidity or mortality occurred in 3.7% of patients without anemia, 5.2% of patients with mild anemia, and 7.1% of patients with moderate to severe anemia (P < .001). After adjustment for confounding variables, mild anemia OR = 1.36 (95% CI = 1.28-1.45), and moderate to severe anemia OR = 1.92 (95% CI = 1.72-2.13) were associated with increased odds of morbidity or mortality. Sex, but not race, was a significant effect modifier with men having a greater increase in morbidity or mortality when anemic (P = .02).

CONCLUSIONS

Anemia is associated with increased morbidity or mortality after knee arthroplasty surgery and men have a greater increase in perioperative risk than women when anemic.