Analysis of the Microsized Microwave Atmospheric Satellite (MicroMAS) Communications Anomaly

The Micro-sized Microwave Atmospheric Satellite (MicroMAS) is a dual- spinning 3U CubeSat equipped with a passive microwave spectrometer that operated nine channels near the 118.75-GHz oxygen absorption line. The focus of this first MicroMAS mission (hereafter, MicroMAS-1) was to ob- serve convective thunderstorms, tropical cyclones, and hurricanes from a near-equatorial orbit. A small fleet of Micro-sized Microwave Atmospheric Satellites could yield high-resolution global temperature and water vapor profiles, as well as cloud microphysical and precipitation parameters. MicroMAS-1 was delivered in March 2014 to the launch provider and was deployed from the International Space Station in March 2015. Engineering data and sensor telemetry were successfully downlinked within the first few days of on-orbit operation, but an anomaly prevented the successful validation of the science instrument. This paper discusses the data reconstruction process used to determine the spacecraft state and to diagnose potential failure modes using combi- nations of simulations and engineering models of key components. After analyzing the potential failure modes on both the groundstation and the spacecraft, results indicate that one of the solar panels may have not prop- erly deployed, leading to the most likely cause of failure: damage to the on- board radio transmitter power amplifier. A re-flight mission, MicroMAS-2, has two launches (2a and 2b) planned for 2018.Air Force Office of Scientific Research (Contract FA8721-05-C-0002

Initial Radiance Validation of the Microsized Microwave Atmospheric Satellite-2A

The Micro-Sized Microwave Atmospheric Satellite (MicroMAS-2A) is a 3U CubeSat that launched in January 2018 as a technology demonstration for future microwave sounding constellation missions, such as the NASA Time-Resolved Observations of Precipitation structure and storm Intensity with a Constellation of Smallsats (TROPICS) mission now in development. MicroMAS-2A has a miniaturized 1U 10-channel passive microwave radiometer with channels near 90, 118, 183, and 206 GHz for moisture and temperature profiling and precipitation imaging [4]. MicroMAS-2A provided the first CubeSat atmospheric vertical sounding data from orbit and to date is the only CubeSat to provide temperature and moisture sounding and surface imaging. In this paper, we analyze six segments of data collected from MicroMAS-2A in April 2018 and compare them to ERA5 reanalysis fields coupled with the Community Radiative Transfer Model (CRTM). This initial assessment of CubeSat radiometric accuracy shows biases relative to ERA5 with magnitudes ranging from 0.4 to 2.2 K (with standard deviations ranging from 0.7 to 1.2 K) for the four mid-tropospheric temperature channels and biases of 2.2 and 2.8 K (standard deviations 1.8 and 2.6 K) for the two lower tropospheric water vapor channels.NASA (Award NNX16AM73H

Association Between Diastolic Blood Pressure During Pediatric In-Hospital Cardiopulmonary Resuscitation and Survival

BackgroundOn the basis of laboratory cardiopulmonary resuscitation (CPR) investigations and limited adult data demonstrating that survival depends on attaining adequate arterial diastolic blood pressure (DBP) during CPR, the American Heart Association recommends using blood pressure to guide pediatric CPR. However, evidence-based blood pressure targets during pediatric CPR remain an important knowledge gap for CPR guidelines.MethodsAll children ≥37 weeks' gestation and <19 years old in Collaborative Pediatric Critical Care Research Network intensive care units with chest compressions for ≥1 minute and invasive arterial blood pressure monitoring before and during CPR between July 1, 2013, and June 31, 2016, were included. Mean DBP during CPR and Utstein-style standardized cardiac arrest data were collected. The hypothesis was that DBP ≥25 mm Hg during CPR in infants and ≥30 mm Hg in children ≥1 year old would be associated with survival. Primary outcome was survival to hospital discharge. Secondary outcome was survival to hospital discharge with favorable neurological outcome, defined as Pediatric Cerebral Performance Categories 1 to 3 or no worse than prearrest baseline. Multivariable Poisson regression models with robust error estimates were used to estimate the relative risk of outcomes.ResultsBlinded investigators analyzed blood pressure waveforms during CPR from 164 children, including 60% <1 year old, 60% with congenital heart disease, and 54% after cardiac surgery. The immediate cause of arrest was hypotension in 67%, respiratory decompensation in 44%, and arrhythmia in 19%. Median duration of CPR was 8 minutes (quartiles, 3 and 27 minutes). Ninety percent survived the event, 68% with return of spontaneous circulation and 22% by extracorporeal life support. Forty-seven percent survived to hospital discharge, and 43% survived to discharge with favorable neurological outcome. Maintaining mean DBP ≥25 mm Hg in infants and ≥30 mm Hg in children ≥1 year old occurred in 101 of 164 children (62%) and was associated with survival (adjusted relative risk, 1.7; 95% confidence interval, 1.2-2.6; P=0.007) and survival with favorable neurological outcome (adjusted relative risk, 1.6; 95% confidence interval, 1.1-2.5; P=0.02).ConclusionsThese data demonstrate that mean DBP ≥25 mm Hg during CPR in infants and ≥30 mm Hg in children ≥1 year old was associated with greater likelihood of survival to hospital discharge and survival with favorable neurological outcome

Association Between Diastolic Blood Pressure During Pediatric In-Hospital Cardiopulmonary Resuscitation and Survival

BackgroundOn the basis of laboratory cardiopulmonary resuscitation (CPR) investigations and limited adult data demonstrating that survival depends on attaining adequate arterial diastolic blood pressure (DBP) during CPR, the American Heart Association recommends using blood pressure to guide pediatric CPR. However, evidence-based blood pressure targets during pediatric CPR remain an important knowledge gap for CPR guidelines.MethodsAll children ≥37 weeks' gestation and <19 years old in Collaborative Pediatric Critical Care Research Network intensive care units with chest compressions for ≥1 minute and invasive arterial blood pressure monitoring before and during CPR between July 1, 2013, and June 31, 2016, were included. Mean DBP during CPR and Utstein-style standardized cardiac arrest data were collected. The hypothesis was that DBP ≥25 mm Hg during CPR in infants and ≥30 mm Hg in children ≥1 year old would be associated with survival. Primary outcome was survival to hospital discharge. Secondary outcome was survival to hospital discharge with favorable neurological outcome, defined as Pediatric Cerebral Performance Categories 1 to 3 or no worse than prearrest baseline. Multivariable Poisson regression models with robust error estimates were used to estimate the relative risk of outcomes.ResultsBlinded investigators analyzed blood pressure waveforms during CPR from 164 children, including 60% <1 year old, 60% with congenital heart disease, and 54% after cardiac surgery. The immediate cause of arrest was hypotension in 67%, respiratory decompensation in 44%, and arrhythmia in 19%. Median duration of CPR was 8 minutes (quartiles, 3 and 27 minutes). Ninety percent survived the event, 68% with return of spontaneous circulation and 22% by extracorporeal life support. Forty-seven percent survived to hospital discharge, and 43% survived to discharge with favorable neurological outcome. Maintaining mean DBP ≥25 mm Hg in infants and ≥30 mm Hg in children ≥1 year old occurred in 101 of 164 children (62%) and was associated with survival (adjusted relative risk, 1.7; 95% confidence interval, 1.2-2.6; P=0.007) and survival with favorable neurological outcome (adjusted relative risk, 1.6; 95% confidence interval, 1.1-2.5; P=0.02).ConclusionsThese data demonstrate that mean DBP ≥25 mm Hg during CPR in infants and ≥30 mm Hg in children ≥1 year old was associated with greater likelihood of survival to hospital discharge and survival with favorable neurological outcome

Chest compression rates and pediatric in-hospital cardiac arrest survival outcomes

AimThe primary aim of this study was to evaluate the association between chest compression rates and 1) arterial blood pressure and 2) survival outcomes during pediatric in-hospital cardiopulmonary resuscitation (CPR).MethodsProspective observational study of children ≥37 weeks gestation and <19 years old who received CPR in an intensive care unit (ICU) as part of the Pediatric Intensive Care Unit Quality of CPR Study (PICqCPR) of the Collaborative Pediatric Critical Care Research Network (CPCCRN). Arterial blood pressure and compression rate were determined from manually extracted arterial line waveform data during the first 10 min of CPR. The primary outcome was survival to hospital discharge. Modified Poisson regression models assessed the association between rate categories (80-<100, 100-120 [Guidelines], >120-140, >140) and outcomes.ResultsCompression rate data were available for 164 patients. More than half (98/164; 60%) were <1 year old. Return of circulation was achieved in 148/164 (90%); survival to hospital discharge in 77/164 (47%). Percentage of events with average rate within Guidelines was 32.9%. Compared to Guidelines, higher rate categories were associated with lower systolic blood pressures (>120-140, p = 0.010; >140, p = 0.077), but not survival. A rate between 80-<100 per minute was associated with a higher rate of survival to hospital discharge (aRR 1.92, CI95 1.13, 3.29, p = 0.017) and survival with favorable neurological outcome (aRR 2.12, CI95 1.09, 4.13, p = 0.027) compared to Guidelines.ConclusionNon-compliance with compression rate Guidelines was common in this multicenter cohort. Among ICU patients, slightly lower rates were associated with improved outcomes compared to Guidelines

Functional outcomes among survivors of pediatric in-hospital cardiac arrest are associated with baseline neurologic and functional status, but not with diastolic blood pressure during CPR

AimDiastolic blood pressure (DBP) during cardiopulmonary resuscitation (CPR) is associated with survival following pediatric in-hospital cardiac arrest. The relationship between intra-arrest haemodynamics and neurological status among survivors of pediatric cardiac arrest is unknown.MethodsThis study represents analysis of data from the prospective multicenter Pediatric Intensive Care Quality of cardiopulmonary resuscitation (PICqCPR) Study. Primary predictor variables were median DBP and median systolic blood pressure (SBP) over the first 10min of CPR. The primary outcome measure was "new substantive morbidity" determined by Functional Status Scale (FSS) and defined as an increase in the FSS of at least 3 points or increase of 2 in a single FSS domain. Univariable analyses were completed to investigate the relationship between new substantive morbidity and BPs during CPR.Results244 index CPR events occurred during the study period, 77 (32%) CPR events met all inclusion criteria as well as having both DBP and FSS data available. Among 77 survivors, 32 (42%) had new substantive morbidity as measured by the FSS score. No significant differences were identified in DBP (median 30.5mmHg vs. 30.9mmHg, p=0.5) or SBP (median 76.3mmHg vs. 63.0mmHg, p=0.2) between patients with and without new substantive morbidity. Children who developed new substantive morbidity were more likely to have lower pre-arrest FSS than those that did not (median [IQR]: 7.5 [6.0-9.0] versus 9.0 [7.0-13.0], p=0.01).ConclusionNew substantive morbidity determined by FSS after a pediatric IHCA was associated with baseline functional status, but not DBP during CPR

Association between time of day and CPR quality as measured by CPR hemodynamics during pediatric in-hospital CPR

IntroductionPatients who suffer in-hospital cardiac arrest (IHCA) are less likely to survive if the arrest occurs during nighttime versus daytime. Diastolic blood pressure (DBP) as a measure of chest compression quality was associated with survival from pediatric IHCA. We hypothesized that DBP during CPR for IHCA is lower during nighttime versus daytime.MethodsThis is a secondary analysis of data collected from the Pediatric Intensive Care Quality of Cardiopulmonary Resuscitation Study. Pediatric or Pediatric Cardiac Intensive Care Unit patients who received chest compressions for ≥1 min and who had invasive arterial BP monitoring were enrolled. Nighttime was defined as 11:00PM to 6:59AM and daytime as 7:00AM until 10:59PM. Primary outcome was attainment of DBP ≥ 25 mmHg in infants <1 year and ≥30 mmHg in older children. Secondary outcomes were mean DBP, ROSC, and survival to hospital discharge. Univariable and multivariate analyses evaluated the relationships between time (nighttime vs. daytime) and outcomes.ResultsBetween July 1, 2013 and June 30, 2016, 164 arrests met all inclusion/exclusion criteria: 45(27%) occurred at nighttime and 119(73%) during daytime. Average DBPs achieved were not different between groups (DBP: nighttime 28.3 mmHg[25.3, 36.5] vs. daytime 29.6 mmHg[21.8, 38.0], p = 0.64). Relative risk of DBP threshold met during nighttime vs. daytime was 1.27, 95%CI [0.80, 1.98], p = 0.30. There was no significant nighttime vs. daytime difference in ROSC (28/45[62%] vs. 84/119[71%] p = 0.35) or survival to hospital discharge (16/45[36%] vs. 61/119[51%], p = 0.08).ConclusionsIn this cohort of pediatric ICU patients with IHCA, there was no significant difference in DBP during CPR between nighttime and daytime

The association of immediate post cardiac arrest diastolic hypertension and survival following pediatric cardiac arrest

AimIn-hospital cardiac arrest occurs in >5000 children each year in the US and almost half will not survive to discharge. Animal data demonstrate that an immediate post-resuscitation burst of hypertension is associated with improved survival. We aimed to determine if systolic and diastolic invasive arterial blood pressures immediately (0-20 min) after return of spontaneous circulation (ROSC) are associated with survival and neurologic outcomes at hospital discharge.MethodsThis is a secondary analysis of the Pediatric Intensive Care Quality of CPR (PICqCPR) study of invasively measured blood pressures during intensive care unit CPR. Patients were eligible if they achieved ROSC and had at least one invasively measured blood pressure within the first 20 min following ROSC. Post-ROSC blood pressures were normalized for age, sex and height. "Immediate hypertension" was defined as at least one systolic or diastolic blood pressure >90th percentile. The primary outcome was survival to hospital discharge.ResultsOf 102 children, 70 (68.6%) had at least one episode of immediate post-CPR diastolic hypertension. After controlling for pre-existing hypotension, duration of CPR, calcium administration, and first documented rhythm, patients with immediate post-CPR diastolic hypertension were more likely to survive to hospital discharge (79.3% vs. 54.5%; adjusted OR = 2.93; 95%CI, 1.16-7.69).ConclusionsIn this post hoc secondary analysis of the PICqCPR study, 68.6% of subjects had diastolic hypertension within 20 min of ROSC. Immediate post-ROSC hypertension was associated with increased odds of survival to discharge, even after adjusting for covariates of interest