Acute exposure to hydrazine reported to four United States regional poison centers: reconsidering a paradigm.

INTRODUCTION: Exposures to hydrazines occur during aeronautic and space operations and pose a potential risk to personnel. Historically, extensive preparatory countermeasures have been taken due to concern for severe toxicity. This study seeks to better understand manifestations of acute occupational exposures to hydrazine to guide recommendations for management. MATERIALS AND METHODS: A retrospective database review of records from four United States regional poison centers was conducted of all human exposures to hydrazine, monomethylhydrazine, or 1,1-dimethylhydrazine over two decades. Following case abstraction, descriptive statistics were performed to characterize demographics, manifestations, treatments, and outcomes. RESULTS: One hundred and thirty-five cases were identified, and most were adult males exposed to inhaled hydrazine propellant vapors. Fifty-seven percent of patients were asymptomatic following exposure; otherwise, common symptoms were dyspnea, throat irritation, cough, ocular irritation, and headache. All patients were evacuated or received decontamination, with a few reports of symptomatic treatments, including oxygen supplementation and salbutamol (albuterol). Patients usually recovered quickly and were released after a brief healthcare facility evaluation or observed locally. No patients developed delayed symptoms. Symptoms of severe toxicity were not observed, and there were no deaths. DISCUSSION: Acute exposures to hydrazines during operations within the aerospace industry appear to be limited primarily to mucosal and mild pulmonary irritation without significant neurologic, hepatic, or hematologic toxicity. These findings are contrary to previously established expectations and may be related to low-level exposures or possibly due to current emergency countermeasures. CONCLUSIONS: Care in occupational hydrazine exposure will focus on evacuation, decontamination, and symptomatic management of chemical irritant properties of hydrazines. It is reasonable to manage mild cases outside of a healthcare facility. Continued endeavors in human space exploration and habitation will increase the risk of these exposures, making it imperative that clinicians be comfortable with the care and management of these patients.

The rising threat of peyssonnelioid algal crusts on coral reefs.

For more than a century, coral reefs have been exposed to increasing anthropogenic disturbances that have profoundly altered their community structure. These perturbations continue to challenge coral reefs in new ways as ecological paradigms are recast in the Anthropocene Epoch1. In recent decades, macroalgal blooms have blighted Caribbean reefs2, but the appearance of aggressive peyssonnelioid algal crusts (PAC) that are rapidly increasing in abundance to become dominant members of the benthos on Caribbean and Indo-Pacific reefs is a novel phenomenon in tropical seas3. By pre-empting vacant space, overgrowing corals, deterring the settlement of coral larvae, and favouring a phase transition from coral to algae4, PAC are likely to accelerate the decline in dominance of corals on global reefs (Figure 1).

Inter-comparison of marine microbiome sampling protocols.

Research on marine microbial communities is growing, but studies are hard to compare because of variation in seawater sampling protocols. To help researchers in the inter-comparison of studies that use different seawater sampling methodologies, as well as to help them design future sampling campaigns, we developed the EuroMarine Open Science Exploration initiative (EMOSE). Within the EMOSE framework, we sampled thousands of liters of seawater from a single station in the NW Mediterranean Sea (Service d'Observation du Laboratoire Arago [SOLA], Banyuls-sur-Mer), during one single day. The resulting dataset includes multiple seawater processing approaches, encompassing different material-type kinds of filters (cartridge membrane and flat membrane), three different size fractionations (>0.22 µm, 0.22-3 µm, 3-20 µm and >20 µm), and a number of different seawater volumes ranging from 1 L up to 1000 L. We show that the volume of seawater that is filtered does not have a significant effect on prokaryotic and protist diversity, independently of the sequencing strategy. However, there was a clear difference in alpha and beta diversity between size fractions and between these and "whole water" (with no pre-fractionation). Overall, we recommend care when merging data from datasets that use filters of different pore size, but we consider that the type of filter and volume should not act as confounding variables for the tested sequencing strategies. To the best of our knowledge, this is the first time a publicly available dataset effectively allows for the clarification of the impact of marine microbiome methodological options across a wide range of protocols, including large-scale variations in sampled volume.

Calidad de vida relacionada con la salud bucal en escolares

Introducción: La presencia de factores socioeconómicos, nivel educativo y el acceso a atención sanitaria pueden condicionar los niveles de calidad de vida relacionada con la salud bucal, especialmente en etapas de vida como la niñez. Objetivo: Determinar la asociación de las condiciones orales en la calidad de vida relacionada con la salud bucal en escolares. Métodos: Estudio observacional, descriptivo y transversal desde una base de datos de 144 escolares (11-12 años). La variable dependiente fue calidad de vida relacionada con la salud bucal, medida con el índice Child Oral Impacts on Daily Performances. Se realizó un análisis descriptivo y pruebas de U de Mann Whitney y ji cuadrado, además se aplicó una regresión logística lineal, con un nivel de confianza de 95 % y p< 0,05. Resultados: El 69,44 % (n= 100) presentó muy poca intensidad del impacto. La procedencia presentó diferencias significativas con limpiarse la boca e impacto total (p< 0,05) y el sexo con hablar y estudiar (p< 0,05). De la regresión lineal, la procedencia se asoció a la gravedad del desempeño limpiarse la boca (R2%= 0,039; a= 0,527; b= 0,347; p= 0,017) e impacto total (R2%= 0,036; a= 4,831; b= 4,824; p= 0,023), el sexo presentó asociación con hablar (R2%= 0,034; a= 0,498; b= -0,137; p= 0,026). Conclusión: La intensidad del impacto es muy poca en la calidad de vida relacionada con la salud bucodental; además, la procedencia se asoció con limpiarse la boca e impacto total, mientras que el sexo se asoció con el desempeño hablar; todo ello en escolares de 11 y 12 años.

Introduction: The presence of certain socioeconomic factors, educational level and access to health care can condition the levels of oral health-related Quality of Life, especially in life stages such as childhood. Objective: To determine the association of oral conditions on oral health-related quality of life in students. Methods: Observational, descriptive and cross-sectional study from a database of 144 schoolchildren (11-12 years old). The dependent variable was Quality of Life related to oral health, measured with the Child Oral Impacts on Daily Performances index. A descriptive analysis and Mann Whitney U and Chi-square tests were performed, and a linear logistic regression was applied, with a confidence level of 95% and p< 0,05. Results: The 69.44% (n= 100) presented very low impact intensity. The provenance presented significant differences with cleaning the mouth and total impact (p< 0.05), and sex with talking and studying (p< 0.05). From the linear regression, provenance was associated with severity of cleaning mouth performance (R2%= 0.039, a= 0.527, b= 0.347, p= 0.017) and total impact (R2%= 0.036, a= 4.831, b= 4.824, p= 0.023), sex was associated with talking (R2%= 0.034, a= 0.498, b= -0.137, p= 0.026). Conclusion: The intensity of the impact was very little in the quality of life related to oral health; in addition, the origin was associated with cleaning the mouth and total impact, while gender was associated with speaking; all this in schoolchildren aged 11 and 12.

Flecainide poisoning and prolongation of elimination due to alkalinization.

BACKGROUND: Flecainide is a 1C antidysrhythmic that is primarily used for ventricular tachycardia or premature ventricular contractions when other treatment is ineffective. It has a very narrow therapeutic window which may cause death in a double dose and requires inpatient initiation for cardiac monitoring. Despite established pharmacokinetic data from flecainide in therapeutic dosing, there is negligible data on flecainide toxicokinetics after an intentional overdose. Due to the inherent differences in pharmacokinetic and toxicokinetic principles, rarely can the peak effect or elimination half-life accurately be applied to the poisoned patient after an overdose. In overdose, flecainide can cause a variety of fatal dysrhythmias which may require sodium bicarbonate for stabilization but also may reduce the renal elimination of flecainide, meaning the life-saving treatment may prolong the time of toxicity. CASE REPORT: We present a case of an acute ingestion of flecainide with a known time of ingestion and known amount of ingestion who experienced subsequent life-threatening effects which required endotracheal intubation, sodium bicarbonate, aggressive electrolyte repletion, and multiple days in an intensive care unit. RESULTS: Serial serum and urine samples revealed a prolonged toxic serum concentration of flecainide. CONCLUSION: These results demonstrate the change in elimination kinetics of flecainide in the setting of urinary alkalization which is evident through prolonged morphologic changes present on serial electrocardiograms.

A Fatal Colchicine Ingestion With Antemortem Blood Concentration.

ABSTRACT: Although there are multiple therapeutic uses for colchicine, it is particularly dangerous in the setting of overdose due to an irreversible mechanism of action combined with a narrow therapeutic window. Colchicine is an antimitotic agent that binds tubulin and inhibits microtubule polymerization. This produces a predictable sequence of toxicity beginning with gastrointestinal effects with progression to multiorgan system dysfunction. Unfortunately, there are no specific antidotes for colchicine toxicity after organ injury has occurred, which can lead to tragic consequences. Despite the recognized toxicity, it is exceedingly rare to find a case in the medical literature with a confirmed time of ingestion, amount ingested, data from longitudinal examinations, and laboratory assessments, with a quantitative blood colchicine concentration. We present a case of acute colchicine overdose of 18 mg (approximately 0.25 mg/kg) with subsequent multiorgan failure and death with an antemortem blood colchicine concentration of 14 ng/mL at 18.5 hours after ingestion.

Disposition, outcomes, and lengths of stay due to bupropion overdose at a tertiary care center with a medical toxicology service.

INTRODUCTION: Bupropion is an antidepressant with unique mechanisms of action leading to a narrow therapeutic window. Parallel to increasing indications, there is an increasing number of overdoses and fatalities attributable to bupropion overdose. Due to the serious effects of a bupropion overdose including arrhythmias and early or delayed seizures, these patients necessitate prolonged monitoring with high levels of medical care. In the setting of a tertiary care center with a medical toxicology consult service, our institution is heavily relied upon to manage these patients. This study was performed to provide clarity on the resources used, lengths-of-stay, and treatments provided for these patients. METHODS: All patients at a tertiary care center with an oral bupropion overdose and a medical toxicology consult less than 24 h after the ingestion were included between July 15, 2017 and October 14, 2021. Chart review was performed to determine lengths-of-stay, the unit of disposition, treatments provided, and outcomes. RESULTS: A total of 73 cases were identified with 36 bupropion-only ingestions. Most cases were transferred from outside facilities, developed seizures, had QRS prolongation; and almost a third required intubation. The vast majority were admitted to an ICU and received GABA-A agonists. A median of 1.47 days per case was spent in the ED or ICU. There was an average of 41.9 ED or ICU bed-days per year and 68.5 non-psychiatric bed-days per year occupied by a patient after a bupropion overdose at a single center. CONCLUSIONS: Bupropion overdose necessitates high resource utilization which we believe will increase with the expanding indications for its use.

Initial Experience with F(ab')2 Antivenom Compared with Fab Antivenom for Rattlesnake Envenomations Reported to a single poison center during 2019.

BACKGROUND: There are two Food and Drug Administration (FDA)-approved antivenoms available for rattlesnake envenomations in the United States: the equine-derived F (ab')2 product sold with the brand name Anavip (F (ab')2 AV) and the ovine-derived Fab product sold with the brand name Crofab (FabAV). OBJECTIVE: To compare the clinical outcomes of rattlesnake envenomation patients treated either with FabAV or F (ab')2AV or a combination of these. METHODS: This is a retrospective chart review of all human rattlesnake envenomations requiring antivenom reported to one regional poison control center in 2019. Patients were categorized as receiving F (ab')2 AV, FabAV, or a combination of both. Baseline characteristics included demographics, time between envenomation and administering antivenom, an abbreviated snakebite severity score (ASSS), and the presence of coagulopathy at presentation. RESULTS: There were a total of 123 patients requiring antivenom. Of these, 57 (46.3%) received FabAV, 53 (43.1%) received F (ab')2 AV, and 13 (10.6%) received a combination of these. Those receiving F (ab')2 AV were younger, with an average age of 40.8 (±25.0) years versus 51.3 (±19.9) years (p = 0.0161) for those receiving FabAV. Time between envenomation and antivenom administration, ASSS, and the percentage of those with coagulopathy at presentation were otherwise similar. Patients treated with F (ab')2 AV or FabAV received a similar total number of vials [16.0 vials (±6.1) vs 14.5 vials (±5.4), p = 0.189], but patients treated with F (ab')2 AV were more frequently given additional doses [31 patients (58.5%) vs. 22 FabAV patients (38.6%), p = 0.0051]. In patients with outpatient follow-up for 2 weeks, fewer patients treated with F (ab')2 AV developed late coagulopathy [5 patients (11.1%) vs 22 FabAV patients (48.9%), p = 0.0004]. Adverse events were generally mild and uncommon with no difference in frequency between patients who received either antivenom (2 F (ab')2 AV patients vs 4 FabAV patients, p = 0.6637). CONCLUSIONS: Other than patient age, we found no significant difference in the baseline demographics, time between envenomation and administering antivenom, an abbreviated snakebite severity score (ASSS), and the presence of coagulopathy at presentation between patients receiving F (ab')2 AV or FabAV. Patients receiving F (ab')2 AV were more likely to be given an additional dose beyond the minimum typical treatment course, but less likely to develop late coagulopathy. Adverse events were uncommon and generally mild whether patients received either antivenom.

Prehospital end-tidal CO2 as an early marker for transfusion requirement in trauma patients.

OBJECTIVE: Below normal end-tidal carbon dioxide measurement (ETCO2) is associated with worse outcomes in sepsis and trauma patients as compared to patients with normal ETCO2. We sought to determine if ETCO2 can be used in the prehospital setting to predict transfusion requirement, operative hemorrhage control, or mortality in the first 24 h after admission for trauma. METHODS: This is a retrospective cohort study at a suburban, academic Level 1 Trauma Center. Patients were sequentially identified as prehospital trauma alerts from a single EMS system which requires, per policy, ETCO2 for all traumas. One year of prehospital data was collected and paired with hospital trauma registry data. Comparisons were made between ETCO2 values for patients who required transfusion, operative blood loss control, or who died, and those who did not. RESULTS: Two hundred thirty-five trauma patients were transported via the study EMS system, of which 105 (44.7%) had documented ETCO2 values. Patient mean age was 60 (SD24) years with 59 (56.2%) male. Three patients were intubated prehospital and seven were intubated in the trauma bay. Mean prehospital ETCO2 for those who needed transfusion, surgery, or died (n = 11) was 25.7 (9.1) compared to 30.6 (7.8) for those who did not (p = 0.049). Optimal cutoff for our population was EtCO2 ≤ 27 with a sensitivity of 72.7% (95% CI 32-93) and specificity of 72.2% (62-81). CONCLUSION: Below normal ETCO2 values were associated with increase need for transfusion, operative intervention, and death. Further study is warranted to determine if ETCO2 outperforms other predictors of severe trauma.

An unusual microbiome characterises a spatially-aggressive crustose alga rapidly overgrowing shallow Caribbean reefs.

Several species of crustose coralline algae (CCA) and their associated microbial biofilms play important roles in determining the settlement location of scleractinian corals on tropical reefs. In recent decades, peyssonnelid algal crusts (PAC) have become spatial dominants across large areas of shallow Caribbean reefs, where they appear to deter the recruitment of scleractinians. Our genetic investigations of PAC in St. John, US Virgin Islands, amplifying the large-subunit ribosomal RNA and psbA protein D1 marker genes, revealed them to be identical to Ramicrusta textilis previously reported overgrowing corals in Jamaica. Specimens of PAC sampled from the Honduras were likewise identical, confirming that this crustose alga inhabits the easternmost and westernmost regions of the Caribbean. We also analysed 16S rDNA tag amplicon libraries of the biofilms associated with PAC and sympatric CCA, which is favoured for coral settlement. Our results show that the microbial communities on PAC (vs. CCA) are characterized by significantly lower numbers of the epibiotic bacterial genus Pseudoalteromonas, which facilitates the recruitment and settlement of marine invertebrates. From these data, we infer that PAC are therefore unlikely to be attractive as settlement sites for coral larvae. Given the significant ecological change anticipated on these reefs due to increasing cover of PAC, there is an urgent need to further investigate competitive interactions between PAC and scleractinian corals, and elucidate the role of PAC and their associated microbiomes in accentuating phase shifts from coral to algae on tropical reefs.

The Experience of Pain and Pain Tool Preferences of Hospitalized Youth.

BACKGROUND: An accurate holistic pediatric pain assessment is necessary for quality pain management. Evidence continues to be published indicating inadequacies in pediatric pain management. It is important for clinicians to consider the pain assessment process while caring for youth. AIM: The purpose of this study was to understand the pain experience through focused interviews and to explore how youth use, interpret and understand self-report pain assessment tools including their tool preferences. DESIGN: A qualitative descriptive study using a research developed semi-structured interview guide was conducted with 40 hospitalized youth, 10-17 years (M: 13yr; S.D. 2.4); 21 (52.5%) female on a medical inpatient unit. Interview questions focused on: current pain experience; pain related symptoms; evaluation of pain treatment and preferences for select pain assessment tools: 0-10 Numeric Rating Scale, The Oucher, Faces Pain Scale-Revised, and Adolescent Pediatric Pain Tool (APPT). SETTING: Large tertiary and quaternary care pediatric hospital located in northeastern United States. PARTICIPANTS/SUBJECTS: Hospitalized youth, 10-17 years of age. RESULTS: Analysis of transcribed interviews yielded 3 themes: My Pain Now, Pain Treatment Expectations, and Telling Healthcare Providers about My Pain. Additionally, pain tools preference, assessment frequency, and discussion of how behavior, activity level, and pain expression was different for each youth. APPT was the preferred pain assessment tool. Descriptive words such as sharp, throbbing, and aching were identified most often. Youth identified that activity and pain level often do not match. CONCLUSIONS: Because pain is multi-dimensional, assessing each dimension (quality, location, intensity, and meaning) is key to thorough assessment. Results provide insight into youth preferences influencing clinical practice such as offering options for interventions and having a voice in the pain management process. All nurses caring for children should discuss available pain tools preferably before the child is in pain and assure the child knows how to use the tool.

Points & Pearls: Pediatric community-acquired pneumonia: diagnosis and management in the emergency department

Worldwide, pneumonia is the most common cause of death in children aged < 5 years. Distinguishing viral from bacterial causes of pneumonia is paramount to providing effective treatment but remains a significant challenge. For patients who can be managed with outpatient treatment, the utility of laboratory tests and radiographic studies, as well as the need for empiric antibiotics, remains questionable. This issue reviews viral and bacterial etiologies of community-acquired pneumonia in pediatric patients, offers guidance for obtaining historical information and interpreting physical examination findings, discusses the utility of various diagnostic techniques, and provides recommendations for the treatment of previously healthy and medically fragile children. [Points & Pearls is a digest of Pediatric Emergency Medicine Practice.]

Activity and diversity of methane-oxidizing bacteria along a Norwegian sub-Arctic glacier forefield.

Methane (CH4) is one of the most abundant greenhouse gases in the atmosphere and identification of its sources and sinks is crucial for the reliability of climate model outputs. Although CH4 production and consumption rates have been reported from a broad spectrum of environments, data obtained from glacier forefields are restricted to a few locations. We report the activities of methanotrophic communities and their diversity along a chronosequence in front of a sub-Arctic glacier using high-throughput sequencing and gas flux measurements. CH4 oxidation rates were measured in the field throughout the growing season during three sampling times at eight different sampling points in combination with laboratory incubation experiments. The overall results showed that the methanotrophic community had similar trends of increased CH4 consumption and increased abundance as a function of soil development and time of year. Sequencing results revealed that the methanotrophic community was dominated by a few OTUs and that a short-term increase in CH4 concentration, as performed in the field measurements, altered slightly the relative abundance of the OTUs.

HIV PrEP in the Military: Experience at a Tertiary Care Military Medical Center.

Objectives: We evaluated human immunodeficiency virus (HIV) pre-exposure prophylaxis (PrEP) administration at the Walter Reed National Military Medical Center (WRNMMC), which serves a geographic area at high risk of HIV infection. Methods: Medical records were reviewed for all patients initiating PrEP at WRNMMC from November 1, 2013, to March 30, 2016. Demographic, laboratory, clinical, and risk exposure characteristics and outcomes were described. Results: One hundred fifty-nine patients received PrEP; 133 (84%) patients were active duty, 95 (60%) patients were over 28 yr old. The majority were non-Hispanic Whites (n = 87, 55%). The median men who have sex with men (MSM) risk index score was 18.0 (IQR 12.0-22.0); 20 patients scored less than 10. One hundred and thirty-one (82%) patients remained on PrEP through the evaluation period. Patients mainly discontinued PrEP for service-related or toxicity reasons. Incident STIs occurred in 31 (19%) patients. No cases of HIV seroconversion were observed. Conclusions: In this first description of PrEP utilization in a U.S. military health care system, a significant number of patients were non-Hispanic Whites, well-educated, were older, or were otherwise at low risk for HIV acquisition. Further effort is needed to enhance PrEP use among the higher risk young African-American MSM population, and further studies are needed to determine the cost-effectiveness of PrEP in individuals who are not categorized as high risk.

Pediatric Major Head Injury: Not a Minor Problem.

Traumatic brain injury is a highly prevalent and devastating cause of morbidity and mortality in children. A rapid, stepwise approach to the traumatized child should proceed, addressing life-threatening problems first. Management focuses on preventing secondary injury from physiologic extremes such as hypoxemia, hypotension, prolonged hyperventilation, temperature extremes, and rapid changes in cerebral blood flow. Initial Glasgow Coma Score, hyperglycemia, and imaging are often prognostic of outcome. Surgically amenable lesions should be evacuated promptly. Reduction of intracranial pressure through hyperosmolar therapy, decompressive craniotomy, and seizure prophylaxis may be considered after stabilization. Nonaccidental trauma should be considered when evaluating pediatric trauma patients.

Spatiotemporal Dynamics of Ammonia-Oxidizing Thaumarchaeota in Distinct Arctic Water Masses.

One of the most abundant archaeal groups on Earth is the Thaumarchaeota. They are recognized as major contributors to marine ammonia oxidation, a crucial step in the biogeochemical cycling of nitrogen. Their universal success is attributed to a high genomic flexibility and niche adaptability. Based on differences in the gene coding for ammonia monooxygenase subunit A (amoA), two different ecotypes with distinct distribution patterns in the water column have been identified. We used high-throughput sequencing of 16S rRNA genes combined with archaeal amoA functional gene clone libraries to investigate which environmental factors are driving the distribution of Thaumarchaeota ecotypes in the Atlantic gateway to the Arctic Ocean through an annual cycle in 2014. We observed the characteristic vertical pattern of Thaumarchaeota abundance with high values in the mesopelagic (>200 m) water throughout the entire year, but also in the epipelagic (<200 m) water during the dark winter months (January, March and November). The Thaumarchaeota community was dominated by three OTUs which on average comprised 76% ± 11 and varied in relative abundance according to water mass characteristics and not to depth or ammonium concentration, as suggested in previous studies. The ratios of the abundance of the different OTU types were similar to that of the functional amoA water cluster types. Together, this suggests a strong selection of ecotypes within different water masses, supporting the general idea of water mass characteristics as an important factor in defining microbial community structure. If indeed, as suggested in this study, Thaumarchaeota population dynamics are controlled by a set of factors, described here as water mass characteristics and not just depth alone, then changes in water mass flow will inevitably affect the distribution of the different ecotypes.

Resting Stage of Plankton Diversity from Singapore Coastal Water: Implications for Harmful Algae Blooms and Coastal Management.

Resting strategies of planktonic organisms are important for the ecological processes of coastal waters and their impacts should be taken into consideration in management of water bodies used by multiple industries. We combined different approaches to evaluate the importance of resting stages in Singapore coastal waters. We used molecular approaches to improve the knowledge on Singapore biodiversity, we sampled and extracted cysts from sediments to evaluate the density of resting stages in Johor Strait, and we compared systematically information on Singapore planktonic biodiversity to existing published information on resting stages from these reported organisms. This is the first study evaluating the importance of resting stages in Singapore waters. Above 120 species reported in Singapore are known to produce resting stages though no previous work has ever been done to evaluate the importance of these strategies in these waters. The results from the resting stage survey confirmed 0.66 to 5.34 cyst g-1 dry weight sediment were present in the Johor Strait suggesting that cysts may be flushed by tidal currents into and out of the strait regularly. This also suggest that the blooms occurring in Singapore are likely due to secondary growth of Harmful Algae Bloom species in the water rather than from direct germination of cysts from sediment. Finally, we discuss the importance of these resting eggs for three main national industries in Singapore (shipping, marine aquaculture and provision of drinking water through seawater desalination). We argue that this study will serve as a baseline for some of the future management of Singapore waters.