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Unfractionated heparin (UFH) is a commonly used anticoagulant for pediatric patients undergoing extracorporeal membrane oxygenation (ECMO), but evidence is lacking on the ideal dosing. We aimed to (1) develop a population pharmacokinetic (PK) model for UFH, measured through anti–factor Xa assay; (2) optimize UFH starting infusions and dose titrations through simulations; and (3) explore UFH exposure–clinical outcomes relationship. Data from 218 patients admitted to Utah's Primary Children's Hospital were retrospectively collected. A 1‐compartment PK model with time‐varying clearance (CL) adequately described UFH PK. Weight on CL and volume of distribution and ECMO circuit change on CL were significant covariates. The typical estimates for initial CL and first‐order rate constant to reach steady‐state CL were 0.57 L/(h·10 kg) and 0.02/h. Comparable to non‐ECMO patients, the typical steady‐state CL was 0.81 L/(h·10 kg). Simulations showed that a 75 IU/kg UFH bolus dose followed by starting infusions of 25 and 20 IU/h/kg for patients aged younger than 6 years and 6 years or older, respectively, achieved the therapeutic target in 56.6% of all patients, whereas only 3.1% exceeded the target. The proposed UFH titration schemes achieved the target in more than 90% of patients while less than 0.63% were above the target after 24 and 48 hours of treatment. The median intensive care unit survival time in patients within and below the target at 24 hours was 136 and 66 hours, respectively. In conclusion, PK model of UFH was developed for pediatric patients on ECMO. The proposed UFH dosing scheme attained the anti–factor Xa target rapidly and safely. [ABSTRACT FROM AUTHOR]

This field report describes the design and operations of the Planetary LakeLander (PLL) probe and its ground data systems. LakeLander's primary mission is to characterize the physical, chemical, and biological processes occurring in a high-altitude lake, and how they are being impacted by rapid deglaciation. LakeLander's secondary purpose is to test operation concepts for future exploration of Titan's lakes. The LakeLander probe is a permanently anchored buoy that measures both surface meteorology and water quality parameters in the top 40 m of the water column. The concept of operations calls for the probe to continue collecting and downlinking data through the Andean winter, when the lake is inaccessible; this drives the power system design and forces a strong focus on system reliability, analogous to a space mission. The PLL ground data system provides the central archive of downlinked data. They are structured around a unified data-sharing web site that includes tools for mapping, data visualization, documentation, and numerical analysis. The web site provides a hub for engaging the science team and enables interdisciplinary collaboration. This report concludes with lessons learned during field deployment and several months of remote operations on the lake. Among the conclusions: (1) the choice to use an off-the-shelf profiling system has proven wise; (2) effective maintenance of a long-lived remote system requires extensive measurement, logging, and display of as many system variables as possible; and (3) the visualization sandbox component of the data-sharing web site has made numerical analysis of probe data much easier and more accessible to the entire interdisciplinary science team. [ABSTRACT FROM AUTHOR]