Single-Site Review of Spinal Cord Protection Protocols Including the Utilization of Spinal Drains versus Medical Management with Branched Endovascular Aortic Repair.

BACKGROUND: Spinal cord ischemia (SCI) continues to be a devastating complication after repair of thoracoabdominal aortic aneurysms. The objective of this review is to present our single-center outcomes after the implementation of a standardized neuroprotective protocol following branched endovascular aortic repair. METHODS: A standardized neuroprotective protocol including preoperative steroids, acetazolamide, intraoperative hemodynamic parameters, and postoperative treatment goals was initiated in November 2019. Physician-modified branched endovascular repairs were completed at a single center from 2012 to 2021 with outcomes reviewed both before (n = 107) and after (n = 67) the implementation of the neuroprotective protocol. The primary end point was the incidence of any SCI event at 30 days. Secondary end points included all-cause mortality, stroke, myocardial infarction, and renal failure at 30 days. Patients with Crawford extents I-III, renal failure, or necessitating emergent repair were deemed high risk for SCI events and underwent a subset analysis. Survivability after SCI was estimated using Kaplan-Meier tables. RESULTS: Of the 174 consecutive patients treated, the 67 patients treated following implementation of the neuroprotective protocol were more likely to have experienced a prior myocardial infarction (26.9% vs. 14%; P = 0.0466) and have a history of chronic obstructive pulmonary disease (64.3% vs. 45.8%; P = 0.02). This group was more likely to be treated for paravisceral aneurysms (53.7% vs. 24.3%; P = 0.0002). Postprotocol implementation, spinal drain use was lower (6% vs. 38.3%; P = <0.0001) with 100% of these drains placed in urgent or unstaged thoracoabdominal aortic aneurysm repairs as a part of the protocol. Rates of any SCI event among all patients before and after implementation of the protocol were 9.3% (n = 10 of 107) and 6% (n = 4 of 67; P = 0.57), respectively. In comparison, the protocol significantly reduced SCI rates to 0 (0% vs. 17.1%; P = 0.0407) in high-risk patients. Frequency of renal failure was reduced (3% vs. 14%; P = 0.018) after initiation of the protocol. Patients in the postprotocol group had significantly improved 1-year mortality rate (9% vs. 27.1%; P = 0.0035) and renal failure rates (2% vs. 15%; P = 0.018). Regression models indicated that patients in the postprotocol group had lower likelihood of mortality and renal failure than patients in preprotocol group (P < 0.05) and that spinal drain reduced mortality (P < 0.1). CONCLUSIONS: Implementation of a standardized neuroprotective protocol that focuses on medical management and fluid dynamics may significantly reduce risk of SCI after branched endovascular repairs, with the most significant improvement of SCI outcomes involving those at greatest risk for developing SCI. Also noteworthy, there was significant improvement to 1-year survivability after the implementation of this neuroprotective protocol.

Short-term Cost Comparison of Systemic Heparin Therapy vs. Catheter Directed Thrombolysis for the Treatment of Massive and Submassive Pulmonary Embolism with Long-Term Chronic Pulmonary Hypertension Cost Model.

INTRODUCTION: Pulmonary embolism (PE) is a significant disease process that affects an estimated 117 cases per 100,000 person-years. Chronic pulmonary hypertension (CPH) is a long-term complication associated with acute PE which has a significant cost to treat, ranging from $98,000-117,000. METHODS: A retrospective chart review of 341 patients from January 2011 to November 2018 who presented with massive or submassive PE and were treated with either systemic heparin therapy or catheter directed thrombolysis (CDT). The results of the short-term cost analysis and pulmonary hypertension rates from data collected was then used in a long-term cost model using a standardized 100 patient model. RESULTS: Treatment with CDT resulted in fewer bleeding complications (4.2 percent vs. 13.8 percent, p=0.005), a shorter length of stay, a greater percentage of patients returning to their prior living conditions (89.0 percent vs. 79.3 percent, p=0.042), and a lower rate of chronic pulmonary hypertension at 12 months (6.3 percent vs. 15.9 percent, p=0.030) than those treated with systemic heparin. The expense of treatment utilizing CDT was greater than those undergoing systemic heparin treatment with a difference of approximately $31,000 (p=0.001) though our cost model showed the heparin group to have a higher cost over time. CONCLUSIONS: For patients with massive or submassive PE, this study demonstrated a significant long-term cost savings and improved outcomes for patients treated with catheter directed thrombolysis when compared to systemic heparin administration.

Rational Design of Memory-Based Sensors: the Case of Molecular Calorimeters.

Thermodynamic characterization is crucial for understanding molecular interactions. However, methodologies for measuring heat changes in small open systems are extremely limited. We document a new approach for designing molecular sensors, that function as calorimeters: sensors based on memory. To design a memory-based sensor, we take advantage of the unique kinetic properties of nucleic acid scaffolds. Particularly, we elaborate on the differences in folding and unfolding rates in nucleic acid quadruplexes. DNA-based i-motifs unfold fast in response to small heats but do not fold back when the system is equilibrated with surroundings. We translated this behavior into a molecular memory function that enables the measurement of heat changes in open environments. The new sensors are biocompatible, operate homogeneously, and measure small heats released over long time periods. As a proof-of-concept, we demonstrate how the molecular calorimeters report heat changes generated in water/propanol mixing and in ligand/protein binding.

Quantitation without Calibration: Response Profile as an Indicator of Target Amount.

Quantitative assessment of biomarkers is essential in numerous contexts from decision-making in clinical situations to food quality monitoring to interpretation of life-science research findings. However, appropriate quantitation techniques are not as widely addressed as detection methods. One of the major challenges in biomarker's quantitation is the need to have a calibration for correlating a measured signal to a target amount. The step complicates the methodologies and makes them less sustainable. In this work we address the issue via a new strategy: relying on position of response profile rather than on an absolute signal value for assessment of a target's amount. In order to enable the capability we develop a target-probe binding mechanism based on a negative cooperativity effect. A proof-of-concept example demonstrates that the model is suitable for quantitative analysis of nucleic acids over a wide concentration range. The general principles of the platform will be applicable toward a variety of biomarkers such as nucleic acids, proteins, peptides, and others.

Breast milk DHA levels may increase after informing women: a community-based cohort study from South Dakota USA.

BACKGROUND: Docosahexaenoic acid (DHA), an omega-3 fatty acid found in breast milk, has many health benefits for both mother and baby. A 2007 meta-analysis found U.S. women had breast milk DHA levels (0.20% of total fatty acids) below the worldwide mean (0.32%). In 2008, international dietary recommendations were made for pregnant and lactating women to consume 200 mg of DHA per day. This community-based study aimed to define current milk DHA levels from upper Midwest USA lactating mothers and to determine if providing information about their own level along with dietary recommendations would incite changes to increase breast milk DHA content. METHODS: New mothers attending lactation classes or using hospital pumping rooms in Sioux Falls, South Dakota, USA participated by providing one drop of breast milk on a card for fatty acid analysis at baseline and 1 month after initial reporting. DHA levels were analyzed by gas chromatography. Mothers received a report of their own breast milk level along with dietary recommendations on DHA intake for lactating women. Median baseline and follow-up DHA levels were determined and differences were compared by Wilcoxon signed-rank test. RESULTS: At baseline, breast milk DHA content (n = 84) was highly variable (range 0.05 to 0.73%) with a median of 0.18% (IQR, 0.13, 0.28; mean ± SD, 0.22 ± 0.13%), well below the worldwide average (0.32%). Women who reported taking DHA supplements (n = 43) had higher levels than those who did not (0.23% vs. 0.15%, P < 0.0001). In a subset of 60 mothers who submitted a second sample, median breast milk DHA content increased from 0.19 to 0.22% (P < 0.01). CONCLUSIONS: Findings suggest that providing nursing mothers with their breast milk DHA level and education about DHA intake while breastfeeding motivates change to increase DHA levels.