Rationale Multiple anecdotal reports describe patients with COVID-19 presenting with what is referred to as silent hypoxemia (without dyspnea, tachypnea, or respiratory distress). However, there is a paucity of literature on this problem. We conducted a study to determine the prevalence of silent hypoxemia in patients with COVID-19 infection at presentation in the emergency department (ED) or on admission, and compared it with that of patients with pneumonia by any other etiology at Memorial Hermann Health System. In addition, we analyzed the differences between clinical, laboratory, hospital utilization, and mortality. Methods From electronic medical records, we identified pneumonia patients with a positive result for coronavirus on reverse transcriptasepolymerase chain reaction (RT-PCR) nasopharyngeal swab test, or diagnosis of pneumonia by influenza or any other etiology for one year, presenting to the ED or admitted to any MHHS hospital. We extracted age, sex, race/ethnicity, vital signs, oxygen saturation, intensive care unit (ICU) admission, and hospital stay for all patients. Results A total of 17,475 COVID-19 patients were compared with 2,343 patients with influenza/pneumonia of any etiology. The two groups were similar with respect to age, sex, and ethnicity. The frequency of silent hypoxemia was greater in the COVID-19 (n=232, 1.3%) group compared to influenza/pneumonia (n= 3, 0.13%) patients (p<0.001). For patients with an oxygen saturation < 90, the proportion who had silent hypoxemia was 11.7% (232/1981) in the COVID-19 patients and 2.6% (3/117) in the influenza and other viral pneumonia patients. Between COVID-19 patients admitted to the hospital, patients with symptomatic hypoxemia had a longer hospital stays (median: 11 days, IQR: 6-22) compared to those with silent hypoxemia (median: 8 days, IQR: 4-18) (p=0.001). The symptomatic hypoxemia group was more likely to be admitted to the ICU (n=457, 26.1%) compared to the silent hypoxemic patients (n=33, 15.5%) (p<0.001) and the mortality rate was higher (n=454, 26.0%) vs (36, 15.5%) (p=0.001). Conclusion The prevalence of silent hypoxemia for adults with viral pneumonia who were seen in the ED or hospitalized in a 17- hospital system in Houston, was higher in the COVID-19 infection patient group compared to patients with other pneumonias or any other etiology. Among the COVID-19 subjects, those with symptomatic hypoxemia had worse outcomes compared to those with silent hypoxemia. More studies are needed to confirm these findings.

Objectives: Opioid-sparing multi-modal analgesia is a key component of enhanced recovery programmes. In cancer surgery, opioids may increase the risk of recurrence through direct immunomodulatory effects and from side effects negatively impacting postoperative recovery resulting in a delay for patients’ returning to intended oncological treatment1. In our hospital, intrathecal diamorphine (ITD) is part of our enhanced recovery protocol for robotic-assisted radical prostatectomy (RARP) patients. With intrathecal opioids known to reduce post-operative morphine requirements in laparoscopic colorectal surgery2, our aim was to investigate if ITD had the same opioid sparing ability in RARP patients.

This study examines current soil contamination in an Australian industrial city, Newcastle. Public (roadside verges and parks) and private (homes) surface soils (n=170) contained metal(loid)s elevated above their respective Australian Health Investigation Levels (HIL). Lead (Pb), the most common contaminant in the city, exceeds the HIL for residential soils (HIL-A, 300mg/kg) in 88% of private soils (median: 1140mg/kg). In-vitro Pb bio-accessibility analysis of selected soils (n=11) using simulated gastric fluid showed a high affinity for Pb solubilisation (maximum Pb concentration: 5190mg/kg, equating to 45% Pb bio-accessibility). Highly soluble Pb-laden Fe- and Mn-oxides likely contribute to the bio-accessibility of the Pb. Public and private space surface soils contain substantially less radiogenic Pb (range: 208Pb/207Pb: 2.345–2.411, 206Pb/207Pb: 1.068–1.312) than local background soil (208Pb/207Pb: 2.489, 206Pb/207Pb: 1.198), indicating anthropogenic contamination from the less radiogenic Broken Hill type Pb ores (208Pb/207Pb: 2.319, 206Pb/207Pb: 1.044). Source apportionment using Pb isotopic ratio quantification and soil mineralogy indicate the city's historic copper and steel industries contributed the majority of the soil contaminants through atmospheric deposition and use of slag waste as fill material. High-temperature silicates and oxides combined with rounded particles in the soil are characteristic of smelter dust emissions. Additionally, a preliminary investigation of polycyclic aromatic hydrocarbons in soils, sometimes associated with ferrous metal smelting, coal processing or burning of fossil fuels, shows that these too pose a health exposure risk (calculated in comparison to benzo(a)pyrene: n=12, max: 13.5mg/kg, HIL: 3mg/kg).

This article demonstrates the potential of the digital image correlation (DIC) method to provide accurate full-field deformation measurements and successfully monitor the development of damage during seismic excitation of a partially grouted reinforced masonry building. The building was subjected to a sequence of earthquake ground motion records using the Large High Performance Outdoor Shake Table at the University of California, San Diego. The DIC setup was capable of measuring surface deformations of the single-story building with high frame rate cameras located at a distance greater than 50ft away. The accuracy of the measurements was assessed with data obtained using mounted displacement transducers. The full-field deformation data collected by the DIC system was capable to detect strain localization patterns associated with the onset of wall cracking before it could be shown by the displacement sensor data or by post mortem visual inspection. The research findings reported herein demonstrate, for the first time to the authors' best knowledge, the potential of in situ monitoring of actual structures for damage induced by non-stationary loading profiles using optical metrology. Copyright (c) 2016 John Wiley & Sons, Ltd.

Frequent parental visits are likely to benefit infants in a neonatal intensive care unit (NICU), particularly extremely low birth weight (ELBW; ⩽1000 g) survivors. Parking costs (⩾$10 per visit in our center) may deter visitation, especially for low-income parents. We assessed whether free parking (FP) decreased survivors’ length of stay (LOS). Parents (N=138) of ELBW infants (7 to 14 days old) were randomized to usual care (UC; n=66) or FP (n=72). The primary outcome was LOS. Among survivors (n=116), LOS was not significantly less with FP than UC (means: FP=89, UC=102 days, P=0.22; medians: FP=82, UC=84 days, P=0.30). Groups did not differ significantly on proportion of visit days (FP=0.69, UC=0.72, P=0.47), parental involvement, knowledge/skills and satisfaction. Post hoc analyses found that parents with a greater income, a car and fewer children visited more. More potent interventions than FP are needed to increase parental visits and reduce LOS for ELBW infants in disadvantaged urban populations.

Background: Arterial tortuosity is emerging as an imaging marker of adverse events in aortopathy, but quantification has focused on patients with Marfan and Loeys-Dietz syndromes. Our objective was to characterize vertebral artery tortuosity among a variety of aortopathy phenotypes and genotypes. Methods: We performed a retrospective analysis of patients ≤50 years old with at least one of the following: aortic dilation or dissection, bicuspid aortic valve (BAV), or a genotype associated with aortopathy. Patients included were either enrolled in GenTAC or were cared for at our institution, and had undergone a magnetic resonance or computed tomography angiogram that included the vertebral arteries. The disease-causing gene mutation was available for a subset of the patients. The vertebral artery tortuosity index (VTI) was utilized to quantify tortuosity, and was compared among phenotypes and genotypes. Increased tortuosity was defined as ≥2SD above the mean VTI of previously reported controls undergoing evaluation to exclude arrhythmogenic right ventricular dysplasia (mean 4.5±2.5, cutoff=10.5). Results: We included 456 patients, of median age 29 years (IQR 15-40 years), and 58% male. The figure shows VTI by phenotype and genotype. VTI was higher in all phenotypic groups than controls (p ≤0.01 for all). All genotypes (for which n>1) had increased VTI compared to controls (p≤0.01 for all). Patients with TGFBR2 mutations had significantly greater VTI (median 59, IQR 20-85) than those with FBN1 mutations (median 25, IQR 13-51, p=0.01); there was no difference in VTI between TGFBR1 (median 19, IQR 12-64) and FBN1 mutations (p=0.79). There was no overall correlation between age and VTI; when evaluated by diagnosis, there was a weak correlation in MFS (Spearman's rho=0.213, p=0.01). Conclusions: Increased arterial tortuosity as measured by VTI is present in many phenotypes and genotypes associated with aortopathy, and is not limited to those with mutations in TGFBR1/2.

Background In pilot studies, increased vascular tortuosity is associated with adverse outcomes in children and young adults withheritable thoracic aortic disease, specifically Marfan syndrome (MFS) and Loeys Dietz syndrome (LDS). It is known that vertebral artery tortuosity is highly prevalent in older adults who do not have heritable thoracic aortic disease. We hypothesized that tortuosity increases with age in patients with aortic disease <50 years old.

CONTEXT:Neonatal meningitis is associated with significant morbidity and mortality. We speculated that meningitis may be underdiagnosed among very low birth weight (VLBW) infants because of the failure to perform lumbar punctures (LPs) in infants with suspected sepsis.OBJECTIVE:This study was undertaken to review the epidemiology of late-onset meningitis in VLBW (401-1500 g) infants and to evaluate the concordance of cerebrospinal fluid (CSF) and blood culture (BC) results.METHODS:VLBW infants (excluding those with intraventricular shunts) born at centers of the National Institute of Child Health and Human Development Neonatal Research Network from September 1, 1998, through December 31, 2001, were studied. Late-onset meningitis was defined by culture-based criteria and classified as meningitis with or without associated sepsis. Unadjusted comparisons were made using chi2 tests and adjusted comparisons using regression models.RESULTS:Of 9641 VLBW infants who survived >3 days, 2877 (30%) had > or = 1 LPs, and 6056 (63%) had > or = 1 BC performed after day 3. One hundred thirty-four infants had late-onset meningitis (1.4% of all patients; 5% of those with an LP). Pathogens associated with meningitis were similar to those associated with sepsis. One third (45 of 134) of the infants with meningitis had negative BCs. Lower gestational age and prior sepsis increased risk for meningitis. Compared with uninfected infants, those with meningitis had a longer time on mechanical ventilation (28 vs 18 days), had longer hospitalizations (91 vs 79 days), were more likely to have seizures (25% vs 2%), and were more likely to die (23% vs 2%).CONCLUSIONS:Meningitis is a serious complication among VLBW infants, associated with increased severity of illness and risk of death. Of note, one third of the infants with meningitis had meningitis in the absence of sepsis. Because CSF cultures were performed only half as often as BCs, this discordance in blood and CSF culture results suggests that meningitis may be underdiagnosed among VLBW infants.

BACKGROUNDGlutamine is one of the most abundant amino acids in both plasma and human milk and may be conditionally essential in premature infants. However, glutamine is not provided by standard intravenous amino acid solutions.OBJECTIVEWe assessed the effect of parenteral glutamine supplementation on plasma amino acid concentrations in extremely low-birth-weight infants receiving parenteral nutrition (PN).DESIGNA total of 141 infants with birth weights of 401-1000 g were randomly assigned to receive a standard intravenous amino acid solution that did not contain glutamine or an isonitrogenous amino acid solution with 20% of the total amino acids as glutamine. Blood samples were obtained just before initiation of study PN and again after the infants had received study PN (mean intake: 2.3 +/- 1.0 g amino acids x kg(-1) x d(-1)) for approximately 10 d.RESULTSInfants randomly assigned to receive glutamine had mean plasma glutamine concentrations that increased significantly and were approximately 30% higher than those in the control group in response to PN (425 +/- 182 and 332 +/- 148 micromol/L for the glutamine and control groups, respectively). There was no significant difference between the 2 groups in the relative change in plasma glutamate concentration between the baseline and PN samples. In both groups, there were significant decreases in plasma phenylalanine and tyrosine between the baseline and PN samples; the decrease in tyrosine was greater in the group that received glutamine.CONCLUSIONSIn extremely low-birth-weight infants, parenteral glutamine supplementation can increase plasma glutamine concentrations without apparent biochemical risk. Currently available amino acid solutions are likely to be suboptimal in their supply of phenylalanine, tyrosine, or both for these infants.

CONTEXT Inner-city high-risk infants often receive limited and fragmented care, a problem that may increase serious illness. OBJECTIVE To assess whether access to comprehensive care in a follow-up clinic is cost-effective in reducing life-threatening illnesses among high-risk, inner-city infants. DESIGN Randomized controlled trial. SETTING AND PARTICIPANTS A total of 887 very-low-birth-weight infants born in a Texas county hospital between January 1988 and March 1996 and followed up in a children's hospital clinic. One hundred four infants who became ineligible or died after randomization but before nursery discharge were excluded from the analysis. INTERVENTIONS Infants were randomly assigned to receive routine follow-up care (well-baby care and care for chronic illnesses; n = 441) or comprehensive care (which included the components of routine care plus care for acute illnesses, with 24-hour access to a primary caregiver; n = 446). MAIN OUTCOME MEASURES Life-threatening illnesses (ie, causing death or hospital admission for pediatric intensive care) occurring between nursery discharge and age 1 year, assessed by blinded evaluators from inpatient charts and state Medicaid and vital statistics records; and hospital costs (estimated from department-specific cost-to-charge ratios). RESULTS Comprehensive care resulted in a mean of 3.1 more clinic visits and 6.7 more telephone conversations with clinic staff (P<.001 for both). One-year outcomes were unknown for fewer comprehensive-care infants than routine-care infants (9 vs 28; P =.001). Identified deaths were similar (11 in comprehensive care vs 13 in routine care; P =.68). The comprehensive-care group had 48% fewer life-threatening illnesses (33 vs 63; P<.001), 57% fewer intensive care admissions (23 vs 53; P =.003), and 42% fewer intensive care days (254 vs 440; P =.003). Comprehensive care did not increase the mean estimated cost per infant for all care ($6265 with comprehensive care and $9913 with routine care). CONCLUSION Comprehensive follow-up care by experienced caregivers can be highly effective in reducing life-threatening illness without increasing costs among high-risk inner-city infants. JAMA. 2000;284:2070-2076.

BACKGROUND:Because of concern that feedings may increase the risk of necrotizing enterocolitis, some high-risk infants have received prolonged periods of parenteral nutrition without enteral feedings. Providing minimal enteral feedings during this period of parenteral nutrition was developed as a strategy to enhance feeding tolerance and decrease time to reach full feedings. OBJECTIVES:For high-risk neonates receiving parenteral feedings, to assess the effect of minimal enteral nutrition (MEN) compared to no enteral nutrient intake on measures of feeding tolerance and neonatal outcome. SEARCH STRATEGY:Searches were performed of the Oxford Database of Perinatal Trials, MEDLINE, abstracts and conference proceedings, references from relevant publications in the English language, and studies identified by personal communication. SELECTION CRITERIA:Only randomized or quasi-randomized clinical trials were considered. Trials were included if they enrolled high-risk infants randomly assigned to receive minimal enteral feedings (defined as dilute or full strength feedings providing <= 25 kcal/kg/d for >= 5d) or no enteral nutrient intake (no feedings or water only). DATA COLLECTION AND ANALYSIS:The two reviewers reached consensus for inclusion of trials. Data regarding clinical outcomes were extracted and evaluated by the two reviewers independently of each other. Authors were contacted as needed and feasible to clarify or provide missing data. The specific data that were needed were requested in writing. MAIN RESULTS:Among infants given minimal enteral nutrition (MEN), there was an overall reduction in days to full enteral feeding, total days that feedings were held, and total hospital stay. There was no discernible effect on necrotizing enterocolitis. REVIEWER'S CONCLUSIONS:The evidence of benefit from MEN in these analyses is not convincing for a variety of reasons--the inherent difficulty of assessing enteral feedings in high-risk infants, the small size and methodologic limitations of the studies to date, unexplained heterogeneity with respect to some of the apparent benefits, the potential for bias to affect the findings in unblinded studies, and the unexcluded possibility that MEN might increase necrotizing enterocolitis. For these reasons, it is unclear whether MEN should be used in lieu of an equal period of time without enteral feedings.

BACKGROUND:Very premature infants fed by gavage are unable to regulate their own enteral intake. Therefore the rate at which feedings are advanced must be determined by caregivers. While advancing feedings too rapidly may increase the risk of necrotizing enterocolitis, advancing feedings too slowly might result in undernutrition or prolonged hospital stay. OBJECTIVES:For low-birth-weight premature infants receiving parenteral fluids, to assess the effect of different rates of advancement of enteral feedings beginning at the same age on measures of feeding tolerance and neonatal outcome. SEARCH STRATEGY:Search strategies included a Medline search and a search of the Oxford Database of Perinatal Trials; additional references were sought in review articles, relevant chapters of textbooks, a previous systematic review, recent American Pediatric Society - Society for Pediatric Research abstracts, personal files, and personal communication. SELECTION CRITERIA:Only randomized or quasi-randomized trials were considered. Trials were included if premature low-birth-weight infants were studied and if the strategies being compared were different rates of advancement of feedings (accomplished by either differences in volume or concentration) with the onset of feedings at the same postnatal age in each group. DATA COLLECTION AND ANALYSIS:The two reviewers reached consensus for inclusion of trials. Data regarding clinical outcomes were extracted and evaluated by the two reviewers independently of each other. Authors were contacted as needed and feasible to clarify or provide missing data. The specific data that were needed were requested in writing. MAIN RESULTS:Among infants randomized to more rapid rates of advancement of feedings, there was an overall reduction in days to full enteral feeding and days to regain birth weight. There was no effect on necrotizing enterocolitis (relative risk = 0.90, 95% confidence interval = 0. 46-1.77). REVIEWER'S CONCLUSIONS:There are suggested advantages of more rapid rates of advancing feedings in premature low-birth-weight infants (shorter time to regain birth weight and shorter time to achieve full feedings). It is unclear whether this strategy should be adopted as routine practice because of limited information regarding safety (broad confidence intervals for the incidence of necrotizing enterocolitis) and the effect on length of hospital stay (broad confidence intervals). Because different birth weight ranges and different rates of advancement were used in each of these studies, the ideal rate of advancement remains unclear, particularly for extremely-low-birth-weight infants.