Five-year trends in maternal cardiac arrest in Maryland: 2013-2017

BACKGROUND

The United States (US) maternal mortality rate (MMR) continues to increase. Until recently, the MMR in Maryland (MD) was consistently higher than the national average. Maternal cardiac arrest (MCA) is a rare condition, but can lead to devastating consequences. The incidence of MCA in the US is approximately 6-8 per 100,000 deliveries. To our knowledge there is no contemporary review of MCA in MD. Our primary aim was to determine the incidence of MCA in MD over a 5-year period. Secondary aims were to explore the causes of MCA, as well as characterize maternal and fetal survival.

MATERIALS AND METHODS

Maternal cardiac arrests in Maryland were identified using diagnostic codes and a statewide administrative database for the fiscal years 2013 through 2017. MCA incidence and mortality rates were compared with previously reported national data from 1998 to 2011. Demographic characteristics, medical co-morbidities, obstetric complications, mode of delivery, and fetal outcomes were collected for all patients. The apparent cause of MCA was determined for each patient. Complications and procedures performed in MCAs were also recorded.

RESULTS

In MD, 36 of 47 acute care hospitals provided maternity care. There were 32 cases of MCA in 332,483 deliveries, an estimated incidence rate of 10 per 100,000 deliveries (95% CI = 5-18). The most common apparent cause of MCA was hemorrhage. Maternal survival was 59.4%, while fetal survival was 93.8%. No significant differences were observed in MCA by age group. The incidence of MCA was significantly higher among non-Caucasian patients (24/177,727) when compared to Caucasian patients (8/154,732)(p =.01).

DISCUSSION

Maternal cardiac arrest in Maryland appears to be comparable to the US average, with similar maternal survival rates. Non-Caucasian patients appear to have a disproportionately high rate of these complications. While maternal mortality is high for MCA, fetal survival is excellent. Continued efforts and attention are needed to prevent MCA in underserved minorities and treat postpartum hemorrhage, the leading contributor to MCA over the past decade.

Von Willebrand Factor Concentrate Administration for Acquired Von Willebrand Syndrome- Related Bleeding During Adult Extracorporeal Membrane Oxygenation

OBJECTIVE

To review the use of Von Willebrand Factor (VWF) concentrate for treatment of acquired Von Willebrand syndrome (VWS)-related bleeding in adult extracorporeal membrane oxygenation (ECMO) patients and determine if it was associated with improved VWF laboratory parameters.

DESIGN

Retrospective observational cohort study.

SETTING

Tertiary care academic medical center.

PARTICIPANTS

Adult ECMO patients who received VWF concentrate for treatment of acquired VWS- related bleeding.

INTERVENTIONS

None, observational study.

MEASUREMENTS AND MAIN RESULTS

Ten adult ECMO patients received VWF concentrate for treatment of bleeding with evidence of acquired VWS over a 15-month period. Six patients were on veno-arterial ECMO and 4 were on veno-venous ECMO. The most common site of bleeding was airway or tracheal bleeding. The mean dose of VWF concentrate was 41 IU/kg. Mean VWF antigen was 263 ± 93 IU/dL before treatment and 394 ± 54 after treatment. Mean ristocetin cofactor activity was 127 ± 47 IU/dL before treatment and 240 ± 33 after treatment. The mean VWF ristocetin cofactor activity antigen ratio increased from 0.52 ± 0.14 before treatment to 0.62 ± 0.04 after treatment. Four of 10 patients had complete resolution of their bleeding within 24 hours, and 6 of 10 had complete resolution of their bleeding within 2- to- 4 days. There were 3 patients who had thrombotic events potentially related to VWF concentrate administration. No patient had an arterial thrombosis, stroke, or myocardial infarction.

CONCLUSIONS

VWF concentrate administration increases VWF function in adult ECMO patients, but also may be associated with increased thrombotic risk. Larger studies are needed to determine VWF concentrate's safety, efficacy, and optimal dosing in adult ECMO patients.

Factor VIII and Functional Protein C Activity in Critically Ill Patients With Coronavirus Disease 2019: A Case Series

Critically ill patients with coronavirus disease 2019 (COVID-19) have been observed to be hypercoagulable, but the mechanisms for this remain poorly described. Factor VIII is a procoagulant factor that increases during inflammation and is cleaved by activated protein C. To our knowledge, there is only 1 prior study of factor VIII and functional protein C activity in critically ill patients with COVID-19. Here, we present a case series of 10 critically ill patients with COVID-19 who had severe elevations in factor VIII activity and low normal functional protein C activity, which may have contributed to hypercoagulability.

Early tracheostomy after initiation of venovenous extracorporeal membrane oxygenation is associated with decreased duration of extracorporeal membrane oxygenation support

Timing of tracheostomy placement for patients with respiratory failure requiring venovenous extracorporeal membrane oxygenation support is variable and continues to depend on surgeon preference. We retrospectively reviewed all consecutive adult patients supported with peripheral venovenous extracorporeal membrane oxygenation for acute respiratory distress syndrome at a single institution with the hypothesis that early tracheostomy (within 7 days of extracorporeal membrane oxygenation initiation) decreases the duration of extracorporeal membrane oxygenation support. The primary endpoint was duration of extracorporeal membrane oxygenation support. Secondary endpoints included mortality, overall and intensive care unit length of stay, duration of mechanical ventilation, and time from extracorporeal membrane oxygenation initiation to liberation from ventilator, intensive care unit discharge, and hospital discharge. Overall and extracorporeal membrane oxygenation-associated hospital costs were compared. A total of 50 patients were identified for inclusion (early n = 21; late n = 29). Baseline characteristics including indices of disease severity were similar between groups. Duration of extracorporeal membrane oxygenation support was significantly shorter in the early tracheostomy group (12 vs. 21 days; p = 0.005). Median extracorporeal membrane oxygenation-related costs were significantly decreased in the early tracheostomy group ($3,624 vs. $5,603, p = 0.03). Early tracheostomy placement is associated with decreased time on extracorporeal membrane oxygenation support and reduced extracorporeal membrane oxygenation-related costs in this cohort. Validation in a prospective cohort or a clinical trial is indicated.

Racial Disparity in Cardiac Surgery Risk and Outcome: Report From a Statewide Quality Initiative

BACKGROUND

Racial disparities persist in health care. Our study objective was to evaluate racial disparity in cardiac surgery in Maryland.

METHODS

A statewide database was used to identify patients. Demographics, comorbidities, and predicted risk of death were compared between races. Crude mortality and incidence of complications were compared between groups, as were risk-adjusted odds for mortality and major morbidity or mortality.

RESULTS

The study included 23,094 patients. Most patients were white (75.8%), followed by African American (16.3%), Asian (3.8%), and other races (4.1%). African Americans had a higher preoperative risk for mortality based on The Society of Thoracic Surgeons predictive models compared with white patients (3.0% vs 2.3%, P < .001). African Americans also had higher prevalence of diabetes mellitus, hypertension, peripheral vascular disease, and cerebral vascular disease than white patients. After adjustment for preoperative risk, there was no difference in 30-day mortality between African Americans (odds ratio [OR], 1.26; 95% confidence interval [CI], 0.99-1.59), Asians (OR, 1.22; 95% CI, 0.75-1.97), and other races (OR, 1.18; 95% CI, 0.74-1.89) compared with whites. African Americans had lower risk-adjusted odds of major morbidity or mortality compared with whites (OR, 0.83; 95% CI, 0.75-0.93).

CONCLUSIONS

African American cardiac surgical patients have the highest preoperative risk in Maryland. Patients appeared to receive excellent cardiac surgical care, regardless of race, as risk-adjusted mortality did not differ between groups, and African American patients had lower risk-adjusted odds of major morbidity or mortality than white patients. Future interventions in Maryland should be aimed at reducing preoperative risk disparity in cardiac surgical patients.

Coagulation Factor Levels and Underlying Thrombin Generation Patterns in Adult Extracorporeal Membrane Oxygenation Patients

BACKGROUND

There is a paucity of data on the underlying procoagulant-anticoagulant balance during extracorporeal membrane oxygenation (ECMO). We hypothesized that adult ECMO patients would have an imbalance between procoagulant and anticoagulant factors, leading to an abnormal underlying thrombin generation (TG) pattern.

METHODS

Twenty adult venoarterial (VA) ECMO patients had procoagulant and anticoagulant factor levels measured temporally on ECMO day 1 or 2, day 3, and day 5. In heparin-neutralized plasma, underlying TG patterns, and sensitivity to activated protein C were assessed using calibrated automated thrombogram. TG parameters including lag time, peak TG, and endogenous thrombin potential (ETP) were compared against 5 normal plasma controls (3 males and 2 females) obtained from a commercial supplier. Thrombomodulin (TM) was added to some samples to evaluate for activated protein C resistance.

RESULTS

Procoagulant factors (factor [F] II, FV, and FX) were mostly in normal reference ranges and gradually increased during the first 5 ECMO days (P = .022, <.001, <.001). FVIII levels were elevated at all time points and did not change (P = .766). In contrast, FXI was in the low-normal range but did not increase during ECMO (P = .093). Antithrombin (AT) and protein C levels were below normal but increased during the first 5 ECMO days (P = .002 and P = .014). Heparinase-treated samples showed prolonged lag time, increased peak TG, and increased ETP compared to controls; mean difference in lag time on ECMO day 1 or 2 = 6.0 minutes (99% confidence interval [CI], 2.8-9.2), peak TG = 193.4 (99% CI, 122.5-264.3), and ETP = 1170.4 (99% CI, 723.2-1617.6). After in vitro TM treatment, differences in TG parameters were accentuated and ECMO samples appeared insensitive to TM treatment; mean difference in lag time on ECMO day 1 or 2 = 9.3 minutes (99% CI, 6.2-12.4), peak TG = 233.0 (99% CI, 140.9-325.1), and ETP = 1322.5 (99% CI, 764.8-1880.2). Similar differences in TG parameters were observed on ECMO days 3 and 5.

CONCLUSIONS

Contact activation occurs during ECMO, but procoagulant factor levels are generally preserved. Although heparin-neutralized TG is delayed, peak TG and ETP are supranormal in the setting of high FVIII and low AT and protein C levels. Resistance to TM is also apparent. These changes demonstrate a possible mechanism for hypercoagulability during adult VA ECMO.

Abstract 31: Center-specific Variation in Use of Dual Antiplatelet Therapy Prior to Coronary Surgery: an Outcomes Analysis from the Maryland Cardiac Surgery Quality Initiative

Background: Understanding institutional practices and associated outcomes of patients managed with different dual antiplatelet therapy (DAPT) strategies prior to coronary artery bypass grafting (CABG) could inform practice improvement. We hypothesized that, while receipt of DAPT within 5 days prior to CABG would increase risk for postoperative bleeding, there is institutional variation in preoperative DAPT management.

Methods: A retrospective cohort study was performed using data from the Maryland Cardiac Surgery Quality Initiative (MCSQI), a consortium aggregating data from the 10 hospitals that perform cardiac surgery in Maryland. Isolated CABG patients between 2011 and 2018 were included. The exposure variable of interest was DAPT use within 5 days prior to CABG. The temporal trend in preoperative use of DAPT, heterogeneity in DAPT usage between centers, and perioperative outcomes are reported. The primary outcomes were the STS major morbidity/mortality composite measure and postoperative bleeding events.

Results: The sample included 13,965 patients, of which 23% ( n =3,219) received preoperative DAPT within 5 days of surgery. The percentage of CABG patients treated with DAPT within 5 days decreased over time from 26% in 2011 to 15% in 2018 (Figure, P <0.001 for trend). There was significant heterogeneity in preoperative DAPT use among centers within the state (Figure, P <0.001 for difference in proportions). CABG patients receiving preoperative DAPT were more likely to present with acute MI (49% v 27%, P <0.001) and less likely to present electively (19% v 34%, P <0.001). The ratio of observed-to-expected STS-defined morbidity/mortality was similar between DAPT (O/E 0.85, 95% CI 0.77-0.92) and non-DAPT groups (O/E 0.84, 95% CI 0.79-0.89). Median transfusion of blood products was higher for the DAPT group (1 [0-4] v 0 [0-3], P <0.001). In adjusted models, preoperative DAPT was associated with greater odds of reoperation for bleeding (OR=1.38, P =0.017) and transfusion of ≥2 PRBC units (OR=1.27, P <0.001).

Conclusion: Many isolated CABG patients in the state of Maryland are treated with DAPT within 5 days prior to CABG with notable variation between centers. Given the associated risk of postoperative bleeding, standardized management of preoperative DAPT therapy could improve post-CABG outcomes.

Recreational 'mud fever': Leptospira interrogans induced diffuse alveolar hemorrhage and severe acute respiratory distress syndrome in a U.S. Navy seaman following 'mud-run' in Hawaii

A 23-year-old man with a viral-like prodrome developed sudden severe dyspnea and was found to have renal failure, anemia, shock, and diffuse alveolar hemorrhage with acute respiratory distress syndrome, requiring emergent endotracheal intubation and extracorporeal membrane oxygenation (ECMO). Travel and exposure history from peripheral sources revealed that the patient had participated in a 'mud-run' in Hawaii two weeks prior to symptom onset. The patient was subsequently diagnosed with leptospirosis and treated with ceftriaxone and doxycycline. He was discharged on hospital day 13 with full recovery. Leptospirosis is associated with exposure to water, soil, or other matter contaminated with urine of carrier animals. It has been associated with a multitude of activities over time; most recently recreational water-based activities including 'mud-runs' in endemic areas have been added to the list of routes of exposure. This case underscores the importance of obtaining a thorough epidemiological exposure and travel history and being aware of areas of endemicity for life-threatening infections. Additionally, to our knowledge this is the second case of a patient in the United States treated with ECMO for leptospirosis induced pulmonary hemorrhage.

Regional Cerebral Oximetry as an Indicator of Acute Brain Injury in Adults Undergoing Veno-Arterial Extracorporeal Membrane Oxygenation-A Prospective Pilot Study

Background: Regional cerebral oxygen saturation (rScO2) measured by near-infrared spectroscopy (NIRS) can be used to monitor brain oxygenation in extracorporeal membrane oxygenation (ECMO). ECMO patients that develop acute brain injuries (ABIs) are observed to have worse outcomes. We evaluated the association between rScO2 and ABI in venoarterial (VA) ECMO patients. Methods: We retrospectively reviewed prospectively-collected NIRS data from patients undergoing VA ECMO from April 2016 to October 2016. Baseline demographics, ECMO and clinical characteristics, cerebral oximetry data, neuroradiographic images, and functional outcomes were reviewed for each patient. rScO2 desaturations were defined as a >25% decline from baseline or an absolute value < 40% and quantified by frequency, duration, and area under the curve per hour of NIRS monitoring (AUC rate, rScO2^*min/h). The primary outcome was ABI, defined as abnormalities noted on brain computerized tomography (CT) or magnetic resonance imaging (MRI) obtained during or after ECMO therapy. Results: Eighteen of Twenty patients who underwent NIRS monitoring while on VA ECMO were included in analysis. Eleven patients (61%) experienced rScO2 desaturations. Patients with desaturations were more frequently female (73 vs. 14%, p = 0.05), had acute liver dysfunction (64 vs. 14%, p = 0.05), and higher peak total bilirubin (5.2 mg/dL vs. 1.4 mg/dL, p = 0.02). Six (33%) patients exhibited ABI, and had lower pre-ECMO Glasgow Coma Scale (GCS) scores (5 vs. 10, p = 0.03) and higher peak total bilirubin levels (7.3 vs. 1.4, p = 0.009). All ABI patients experienced rScO2 desaturation while 42% of patients without ABI experienced desaturation (p = 0.04). ABI patients had higher AUC rates than non-ABI patients (right hemisphere: 5.7 vs. 0, p = 0.01, left hemisphere: 119 vs. 0, p = 0.06), more desaturation events (13 vs. 0, p = 0.05), longer desaturation duration (2:33 vs. 0, p = 0.002), and more severe desaturation events with rScO2 < 40 (9 vs. 0, p = 0.05). Patients with ABI had lower GCS scores (post-ECMO initiation) before care withdrawal or discharge than those without ABI (10 vs. 15, p = 0.02). Conclusions: The presence and burden of cerebral desaturations noted on NIRS cerebral oximetry are associated with secondary neurologic injury in adults undergoing VA ECMO.