Targeted Temperature Management: Quantifying the Extent of Serum Electrolyte and Blood Glucose Shifts in Postcardiac Arrest Patients.

This study aims to quantify the extent of electrolyte (potassium, magnesium, and phosphorus) and blood glucose changes during targeted temperature management (TTM), with insight on electrolyte replacements and insulin administration. This was a 3-year retrospective study of patients who underwent TTM via Arctic Sun. Electrolyte and blood glucose values in addition to electrolyte replacements and insulin administrations were collected before, during, and post-TTM. The primary analysis assessed changes in electrolyte and blood glucose values during and after TTM, and the secondary analysis assessed changes before and during, and before and after TTM. The secondary analysis also incorporated amount of electrolyte replacements and insulin administrations patients received before, during, and post-TTM. Sixty patients were included for analysis. Comparing levels during to after TTM, there was a significant increase in potassium (3.7 [0.7]-4.4 [0.7] mmol/L, p < 0.001) and decrease in blood glucose (192 [135]-134 [55] mg/dL, p = 0.001). Comparing levels before to during TTM, there was a significant decrease in potassium (4.3 [0.7]-3.7 [0.7] mmol/L, p < 0.001) and phosphorus (4.8 [3.2]-3.4 [1.5] mg/dL, p = 0.003). Comparing levels before to after TTM, there was a significant decrease in phosphorus (4.5 [2.9]-3.3 [1.2] mmol/L, p = 0.026) and blood glucose (219 [35]-134 [55] mg/dL, p < 0.001). Patients received on average potassium 102 mEq, magnesium 1.9 g, phosphorus 9 mmol, and insulin 94 units. Potassium significantly decreased during and significantly increased after TTM. Phosphorus significantly decreased during TTM and blood glucose significantly decreased after TTM. There were no significant changes in magnesium during the defined time period.

Predictors of Oxygenator Exchange in Patients Receiving Extracorporeal Membrane Oxygenation.

Thrombosis within the membrane oxygenator (MO) during extracorporeal membrane oxygenation (ECMO) can lead to sudden oxygenator dysfunction with deleterious effects to the patient. The purpose of this study was to identify predictors of circuit exchange during ECMO. This is a single-center, retrospective study of all patients who received ECMO at our institution from January 2010 to December 2015. Changes in potential markers were compared on Day 3 vs. Day 0 before MO exchange. Of the 150 patients who received ECMO, there were 58 MO exchanges in 35 patients. Mean ECMO duration was 21.1 (±12.7) days. D-dimer (DD) (µg/mL) (mean difference -2.6; 95% confidence interval [CI]: -4.2 to -1.1; p = .001) increased significantly in the 3 days leading up to MO exchange, whereas fibrinogen (mg/dL) (mean difference 90.7; 95% CI: 41.8-139.6; p = .001), platelet (PLT) count (1,000/µL) (mean difference 23.3; 95% CI: 10.2-36.4; p = .001), and heparin dose (units/h) (mean difference 261.7; 95% CI: 46.3-477.1; p = .02) decreased. Increasing DD or decreasing fibrinogen, PLT count, or heparin dose may indicate an impending need for MO exchange in patients receiving ECMO. Early identification of these changes may help prevent sudden MO dysfunction.

Anticoagulant Bridge Comparison in Mechanical Circulatory Support Patients.

Maintaining mechanical circulatory support (MCS) device patients in a specified therapeutic range for anticoagulation remains challenging. Subtherapeutic international normalized ratios (INRs) occur frequently while on warfarin therapy. An effective anticoagulant bridge strategy may improve the care of these patients. This retrospective review of MCS patients with subtherapeutic INRs compared an intravenous unfractionated heparin (UFH) strategy with a subcutaneous enoxaparin or fondaparinux strategy. Native thromboelastography (n-TEG) was used to evaluate anticoagulant effect with coagulation index (CI) as the primary outcome measure. Enoxaparin 0.5 mg/kg subcutaneously (SC) every 12 hours or fondaparinux 2.5-5 mg SC daily were compared with an initial UFH rate of 5 units/kg/hr and titrated to stated n-TEG goal range. The anticoagulant groups UFH, enoxaparin, and fondaparinux were found to be statistically similar with regard to frequency in n-TEG goal range, above range (hypercoagulability), or below range (hypocoagulability). Clinical outcomes were similar among groups with three gastrointestinal bleeds in UFH, one in enoxaparin, and one in fondaparinux groups. Device thrombosis occurred in one UFH patient, while UFH and fondaparinux groups had one ischemic cerebrovascular accident event each. These strategies provided comparable n-TEG results and clinical outcomes when compared with intravenous UFH. Low-dose enoxaparin or fondaparinux may provide an alternative anticoagulant bridging option in MCS patients presenting with subtherapeutic INR.

Intracranial Hemorrhage in Patients with Durable Mechanical Circulatory Support Devices: Institutional Review and Proposed Treatment Algorithm.

BACKGROUND: Spontaneous intracranial hemorrhage (ICH) is frequently managed in neurosurgery. Patients with durable mechanical circulatory support devices, including total artificial heart (TAH) and left ventricular assist device (LVAD), are often encountered in the setting of ICH. Although durable mechanical circulatory support devices have improved survival and quality of life for patients with advanced heart failure, ICH is one of the most feared complications following LVAD and TAH implantation. Owing to anticoagulation and clinically relevant acquired coagulopathies, ICH should be treated promptly by neurosurgeons and cardiac critical care providers. We provide an analysis of ICH in patients with mechanical circulatory support and propose a treatment algorithm. METHODS: We retrospectively reviewed medical records from 2013-2016 for patients with a durable mechanical circulatory device at Banner-University of Arizona Medical Center Tucson. All patients with suspected ICH underwent computed tomography scan of the brain. Anticoagulation was managed by the cardiothoracic surgeon. RESULTS: In 58 patients, an LVAD (n = 49), TAH (n = 10), or both (n = 1) were implanted. Both acquired von Willebrand disease and spontaneous ICH were diagnosed in 5 patients (8.6%) who underwent LVAD implantation. Seven neurosurgical procedures were performed in 2 patients. The overall mortality rate was 60%. Two patients had little or no deficits after treatment with modified Rankin Scale score of 1 and 2, respectively. CONCLUSIONS: We propose a novel treatment algorithm to manage patients with a LVAD or TAH and ICH, implemented in a multidisciplinary manner to best avoid neurologic and cardiovascular complications.

Advantages and disadvantages of using intravenous tissue Plasminogen activator as salvage therapy for inoperable HeartWare thrombosis.

Device thrombosis is a devastating complication of left ventricular assist devices. The definitive treatment has been device exchange or explant. Evidence of increasing morbidity and mortality with device exchange has shifted strategies toward conservative management. In this report, we detail the use of thrombolytics as salvage therapy in a patient with an occlusive HeartWare ventricular assist device (HeartWare Inc., Framingham, MA) thrombus, resulting in long-term survival without further intervention.

Suspected Heparin-Induced Thrombocytopenia in Patients Receiving Extracorporeal Membrane Oxygenation.

Heparin-induced thrombocytopenia (HIT) is an immune reaction usually secondary to unfractionated heparin. Anticoagulation management is critical in patients while on extracorporeal membrane oxygenation (ECMO) to prevent thromboembolism and for the optimal functioning of the circuit. We identified five patients with respiratory failure at our hospital managed with ECMO in the last 2 years that were treated for HIT. A brief clinical course and their management are discussed. We also briefly review the literature for best evidence for management of such patients.

Novel method using rotational thromboelastography analysis for intraoperative management of device patient with heparin-induced thrombocytopenia.

Heparin-induced thrombocytopenia (HIT) is a prothrombotic disease in response to previous heparin exposure. Direct thrombin inhibitors are suitable candidates for the prophylaxis of thrombosis in patients with HIT. Currently activated clotting time and activated partial thromboplastin time are used to guide dosing and monitor anticoagulation. These assays provide a measure of clot initiation and only account for a small fraction of the coagulation pathway. In this case study we performed rotational thromboelastography (ROTEM) analysis on a patient with HIT implanted with a continuous-flow CentriMag device for left ventricular support. ROTEM evaluation confirmed a decline in activated clotting time values and provided further information regarding intrinsic and extrinsic clotting times. Monitoring ROTEM parameters aided in the detection of coagulopathies and the decision to administer platelet or fresh frozen plasma products. Utilizing ROTEM can guide clinical decisions in transfusions, particularly in patients with HIT, where platelet and fibrinogen levels can be safely maintained to prevent thrombosis.