Impact of a Strategy for Improving Early Management of Acute Pain in the Pediatric Emergency Department

OBJECTIVES

The objective of this study was to measure the impact of an intervention on pain treatment in a pediatric emergency department (ED). The application of interventions to improve pain management in DE has demonstrated diverse effects so far, most of them successful.

METHODS

This is a quasi-experimental before-and-after, longitudinal, prospective study.Patients were collected between January 2020 and December 2021. Principal outcome was the number of patients with moderate or severe pain who received analgesia before 30 minutes to the ED arrival. The intervention consisted of several training sessions for nursing staff, pediatricians, and trauma physicians.

RESULTS

A total of 515 patients were enrolled, 230 during preintervention period and 285 during postintervention period. The percentage of patients receiving analgesia before 30 minutes increased from 24% to 29% and before 60 minutes increased from 31% to 42%. Time to analgesia administration decreased from 43 to 39 minutes.Only 254 patients (49%) received analgesia at some point during their stay in the ED, 137 (26.6%) before 30 minutes and 193 (37.5%) before 60 minutes. The probability of receiving analgesia was greater in patients seen by a pediatrician rather than an orthopedist (59%-37%). Metamizole was the most commonly used drug (48%), followed by ibuprofen and acetaminophen.

CONCLUSIONS

The application strategies to enhance early pain treatment in the ED can improve analgesia administration. Training strategies aimed at healthcare personnel working in the ED can change the way they work and achieve clear benefits for the patient. The treatment of pain in the ED should begin as soon as possible, and in this objective, the involvement of the nursing staff is a priority, because they are the professional who has the best opportunity for the detection and treatment of pain from the moment of triage.

Risk factors associated with indicators of dehydration among migrant farmworkers

OBJECTIVE

Farmworkers are at increased risk of adverse health outcomes related to occupational heat exposure and inadequate access to water, shade, or rest breaks. Presently, there is a dearth of studies examining the prevalence of dehydration and related factors in U.S. farmworkers. Our objectives were to characterize hydration status during typical workdays and to identify risk factors associated with increased dehydration in migrant farmworkers employed in Florida.

METHODS

Urine samples were collected and analyzed for urine specific gravity (USG) 2-3 times per person per day over five days in May 2021 and 2022. Data collection included demographic characteristics, wet-bulb-globe-temperature (WBGT), and information on working conditions (task type, duration, and crop units harvested), fluid intake, clothing worn, and heat safety behaviors. Multivariable mixed regression models were used to evaluate risk factors associated with change in USG levels (continuous) during a work shift.

RESULTS

A total of 111 farmworkers participated in this study providing 1020 cumulative USG measurements, of which 96.8% of end-of-shift USG samples were above 1.020 indicating potential dehydration. In multivariable models, dehydration assessed using change in USG levels significantly declined with age (β = -0.078; 95%CI: 0.150, -0.006) but showed significant increase with body mass index (β = 0.016; 95%CI: 0.003, 0.028), WGBT (β = 0.054; 95%CI:0.044, 0.064), mean shift duration, and state of primary residence. We did not find significant associations of dehydration with type of clothing worn, intake of employer-provided water, or crop units harvested during a shift in this sample of farmworkers.

CONCLUSION

Our findings underscore the need for additional research to evaluate adverse outcomes related to dehydration and to better understand recovery patterns from chronic dehydration across workweeks and harvest seasons in migrant farmworkers.

Dissociable Contributions of Basolateral Amygdala and Ventrolateral Orbitofrontal Cortex to Flexible Learning Under Uncertainty

Reversal learning measures the ability to form flexible associations between choice outcomes with stimuli and actions that precede them. This type of learning is thought to rely on several cortical and subcortical areas, including the highly interconnected orbitofrontal cortex (OFC) and basolateral amygdala (BLA), and is often impaired in various neuropsychiatric and substance use disorders. However, the unique contributions of these regions to stimulus- and action-based reversal learning have not been systematically compared using a chemogenetic approach particularly before and after the first reversal that introduces new uncertainty. Here, we examined the roles of ventrolateral OFC (vlOFC) and BLA during reversal learning. Male and female rats were prepared with inhibitory designer receptors exclusively activated by designer drugs targeting projection neurons in these regions and tested on a series of deterministic and probabilistic reversals during which they learned about stimulus identity or side (left or right) associated with different reward probabilities. Using a counterbalanced within-subject design, we inhibited these regions prior to reversal sessions. We assessed initial and pre-/post-reversal changes in performance to measure learning and adjustments to reversals, respectively. We found that inhibition of the ventrolateral orbitofrontal cortex (vlOFC), but not BLA, eliminated adjustments to stimulus-based reversals. Inhibition of BLA, but not vlOFC, selectively impaired action-based probabilistic reversal learning, leaving deterministic reversal learning intact. vlOFC exhibited a sex-dependent role in early adjustment to action-based reversals, but not in overall learning. These results reveal dissociable roles for BLA and vlOFC in flexible learning and highlight a more crucial role for BLA in learning meaningful changes in the reward environment.

Spinal gunshot wounds: A retrospective, multicenter, cohort study

INTRODUCTION AND OBJECTIVE

To describe the demographic and clinical characteristics and treatment of patients with spinal gunshot wounds across Latin America.

MATERIAL AND METHODS

Retrospective, multicenter cohort study of patients treated for gunshot wounds to the spine spanning 12 institutions across Latin America between January 2015 and January 2022. Demographic and clinical data were recorded, including the time of injury, initial assessment, characteristics of the vertebral gunshot injury, and treatment.

RESULTS

Data on 423 patients with spinal gunshot injuries were extracted from institutions in Mexico (82%), Argentina, Brazil, Colombia, and Venezuela. Patients were predominantly male civilians in low-risk-of-violence professions, and of lower/middle social status, and a sizeable majority of gunshots were from low-energy firearms. Vertebral injuries mainly affected the thoracic and lumbar spine. Neurological injury was documented in n=320 (76%) patients, with spinal cord injuries in 269 (63%). Treatment was largely conservative, with just 90 (21%) patients treated surgically, principally using posterior open midline approach to the spine (n=79; 87%). Injury features distinguishing surgical from non-surgical cases were neurological compromise (p=0.004), canal compromise (p<0.001), dirty wounds (p<0.001), bullet or bone fragment remains in the spinal canal (p<0.001) and injury pattern (p<0.001). After a multivariate analysis through a binary logistic regression model, the aforementioned variables remained statistically significant except neurological compromise.

CONCLUSIONS

In this multicenter study of spinal gunshot victims, most were treated non-surgically, despite neurological injury in 76% and spinal injury in 63% of patients.

Stratification of adolescents across mental phenomena emphasizes the importance of transdiagnostic distress: a replication in two general population cohorts

Characterizing patterns of mental phenomena in epidemiological studies of adolescents can provide insight into the latent organization of psychiatric disorders. This avoids the biases of chronicity and selection inherent in clinical samples, guides models of shared aetiology within psychiatric disorders and informs the development and implementation of interventions. We applied Gaussian mixture modelling to measures of mental phenomena from two general population cohorts: the Avon Longitudinal Study of Parents and Children (ALSPAC, n = 3018) and the Neuroscience in Psychiatry Network (NSPN, n = 2023). We defined classes according to their patterns of both positive (e.g. wellbeing and self-esteem) and negative (e.g. depression, anxiety, and psychotic experiences) phenomena. Subsequently, we characterized classes by considering the distribution of diagnoses and sex split across classes. Four well-separated classes were identified within each cohort. Classes primarily differed by overall severity of transdiagnostic distress rather than particular patterns of phenomena akin to diagnoses. Further, as overall severity of distress increased, so did within-class variability, the proportion of individuals with operational psychiatric diagnoses. These results suggest that classes of mental phenomena in the general population of adolescents may not be the same as those found in clinical samples. Classes differentiated only by overall severity support the existence of a general, transdiagnostic mental distress factor and have important implications for intervention.

Risk Factors for Nonunion Following Ankle Arthrodesis: A Systematic Review and Meta-analysis

BACKGROUND

Nonunion is a postoperative complication after ankle arthrodesis (AA), which leads to increased morbidity and revision rates. Previous studies have identified risk factors for nonunion following AA, but no meta-analysis has been performed to stratify risk factors based on strength of evidence.

METHODS

Abstracts and full-text articles were screened by 2 independent reviewers. Relevant data were extracted from the included studies. Random effects meta-analyses were summarized as forest plots of individual study and pooled random effect results.

RESULTS

Database search yielded 13 studies involving 987 patients were included, and 37 potential risk factors for nonunion. Meta-analysis found 5 significant risk factors for nonunion post-AA. Strong evidence supports male gender (OR: 1.96; 95% CI: 1.13-3.41), smoking (OR: 2.89; 95% CI: 1.23-6.76), and history of operative site infection prior to arthrodesis (OR: 2.40; 95% CI: 1.13-5.09) as predictors for nonunion following AA. There was moderate evidence supporting history of open injury (OR: 5.95; 95% CI: 2.31-15.38) and limited evidence for preoperative avascular necrosis (OR: 13.16; 95% CI: 2.17-79.61) as possible risk factors for nonunion.

CONCLUSION

The results of our meta-analysis suggest that male gender, smoking, and history of operative site infection have strong evidence and that history of open injury and avascular necrosis also have evidence as risk factors for nonunion. Surgeons should be cognizant of these risks when performing AA and closely follow up with patients with the aforementioned risk factors to ensure postoperative success.

LEVELS OF EVIDENCE

Level V: Systematic review of cohort and case-control studies.

Hypothalamic integrity is necessary for sustained weight loss after bariatric surgery: A prospective, cross-sectional study

OBJECTIVE

The hypothalamus is the main integrator of peripheral and central signals in the control of energy homeostasis. Its functional relevance for the effectivity of bariatric surgery is not entirely elucidated. Studying the effects of bariatric surgery in patients with hypothalamic damage might provide insight.

SUMMARY BACKGROUND DATA

Prospective study to analyze the effects of bariatric surgery in patients with hypothalamic obesity (HO) vs. matched patients with common obesity (CO) with and without bariatric surgery.

METHODS

65 participants were included (HO-surgery: n = 8, HO-control: n = 10, CO-surgery: n = 12, CO-control: n = 12, Lean-control: n = 23). Body weight, levels of anorexic hormones, gut microbiota, as well as subjective well-being/health status, eating behavior, and brain activity (via functional MRI) were evaluated.

RESULTS

Patients with HO lost significantly less weight after bariatric surgery than CO-participants (total body weight loss %: 5.5 % vs. 26.2 %, p = 0.0004). After a mixed meal, satiety and abdominal fullness tended to be lowest in HO-surgery and did not correlate with levels of GLP-1 or PYY. Levels of PYY (11,151 ± 1667 pmol/l/h vs. 8099 ± 1235 pmol/l/h, p = 0.028) and GLP-1 (20,975 ± 2893 pmol/l/h vs. 13,060 ± 2357 pmol/l/h, p = 0.009) were significantly higher in the HO-surgery vs. CO-surgery group. Abundance of Enterobacteriaceae and Streptococcus was increased in feces of HO and CO after bariatric surgery. Comparing HO patients with lean-controls revealed an increased activation in insula and cerebellum to viewing high-caloric foods in left insula and cerebellum in fMRI.

CONCLUSIONS

Hypothalamic integrity is necessary for the effectiveness of bariatric surgery in humans. Peripheral changes after bariatric surgery are not sufficient to induce satiety and long-term weight loss in patients with hypothalamic damage.

Sinus tarsi approach in high-risk patients with displaced intra-articular calcaneus fractures: A case series

Purpose

Though research exists regarding calcaneal fractures, the treatment approach for displaced intra-articular calcaneal fractures (DIACF) remains controversial. The most common approach, the extensile lateral approach (ELA), for the treatment of DIACFs has high rates of wound complications reported. In contrast, the sinus tarsi approach (STA) is becoming more popular due to its minimally invasive technique. The objective of this retrospective study is to investigate the incidence of wound complications in high-risk patients with DIACF following operative fixation via the STA.

Methods

Following IRB approval, a retrospective chart review was performed between 2007 and 2013 to assess high-risk patients for the presence of wound complications, including deep infections and delayed wound healing, following the use of STA for the management of DIACF's (n = 36). Demographics, risk factors, and secondary outcomes such as time to surgery were recorded.

Results

Of the 36 high-risk patients included in our study, seven had post-operative complications following operative fixation via the STA. Specifically, four patients had delayed wound healing, and three developed deep infections. Time to surgery had the greatest negative effect on postoperative complications and was influenced by age, sex, and the presence of a concomitant injury.

Conclusion

In conclusion, this study demonstrates that the STA is a viable option for high-risk patients with displaced intra-articular fractures. Additionally, time to surgery should be minimized, when possible, to reduce risks of post-operative complications, including infections and delayed wound healing.

Sex-differences in oral anticoagulation therapy in patients hospitalised with atrial fibrillation: a nationwide cohort study

Background

Important disparities in the treatment and outcomes of women and men with atrial fibrillation are well recognized. Whether introduction of direct oral anticoagulants has reduced disparities in treatment is uncertain.

Methods

All patients who had an incident hospitalization from 2010 to 2019 with non-valvular atrial fibrillation in Scotland were included in this cohort study. Community drug dispensing data were used to determine prescribed oral anticoagulation therapy and comorbidity status. Logistic regression modelling was used to evaluate patient factors associated with treatment with vitamin K antagonists and direct oral anticoagulants.

Results

A total of 172,989 patients (48% women [82,833/172,989]) had an incident hospitalization with non-valvular atrial fibrillation in Scotland between 2010 and 2019. The proportion of patients with thromboembolic risk factors (CHA2DS2VASc score &gt;0 in men and &gt;1 in women) treated with oral anticoagulation therapy increased from 36.8% to 66.3% over this 10-year period. By 2019, factor Xa inhibitors accounted for 83.6% of all oral anticoagulants prescribed, while treatment with vitamin K antagonists and direct thrombin inhibitors declined to 15.9% and 0.6%, respectively. Women were less likely to be prescribed any oral anticoagulation therapy compared to men (adjusted odds ratio, aOR 0.68 [95% CI, CI 0.67–0.70]). This disparity was mainly attributed to vitamin K antagonists (aOR 0.68 [95% CI 0.66–0.70]), whilst there was less disparity in use of factor Xa inhibitors between women and men (aOR 0.92 [95% CI 0.90–0.95]). At 1 year following hospitalization with atrial fibrillation, patients not prescribed oral anticoagulation therapy were more likely to have subsequent major adverse cardiovascular events compared to those prescribed with oral anticoagulation therapy (38.8% [15,380/39,608] versus 17.0% [6,761/39,671] in women and 35.2% [12,977/36,868] versus 16.4% [7,395/45,093] in men).

Conclusions

Women with non-valvular atrial fibrillation were significantly less likely to be prescribed vitamin K antagonists compared to men. Most patients admitted to hospital in Scotland with incident non-valvular atrial fibrillation are now treated with factor Xa inhibitors and this is associated with less treatment disparities between women and men.

Funding Acknowledgement

Type of funding sources: Private grant(s) and/or Sponsorship. Main funding source(s): This study was supported by the British Heart Foundation through a Clinical Research Training Fellowship (FS/18/25/33454), Intermediate Clinical Research Fellowship (FS/19/17/34172), Senior Clinical Research Fellowship (FS/16/14/32023) and a Research Excellence Award (RE/18/5/34216), and a research grant to NHS Lothian from Bristol Myers Squibb Pharmaceuticals Ltd and Pfizer UK Ltd.

Case report of congenital methemoglobinemia: an uncommon cause of neonatal cyanosis

Background

Methemoglobinemia can be an acquired or congenital condition. The acquired form occurs from exposure to oxidative agents. Congenital methemoglobinemia is a rare and potentially life-threatening cause of cyanosis in newborns that can be caused by either cytochrome B₅ reductase or hemoglobin variants known as Hemoglobin M.

Case presentation

A term male infant developed cyanosis and hypoxia shortly after birth after an uncomplicated pregnancy, with oxygen saturations persistently 70–80% despite 1.0 FiO2 and respiratory support of CPAP+ 6 cm H2O. Pre- and post-ductal saturations were equal and remained below 85%. Initial radiographic and echography imaging was normal. Capillary blood gas values were reassuring with normal pH and an elevated pO2. Investigations to rule out hemolysis and end-organ dysfunction were within acceptable range. Given the absence of clear cardiac or pulmonary etiology of persistent cyanosis, hematologic causes such as methemoglobinemia were explored. No family history was available at the time of transfer to our institution. Unconjugated hyperbilirubinemia > 5 mg/dL (442 μmol/L) interfered with laboratory equipment measurement, making accurate methemoglobin levels unattainable despite multiple attempts. Initial treatment with methylene blue or ascorbic acid was considered. However, upon arrival of the presumed biological father, a thorough history revealed an extensive paternal family history of neonatal cyanosis due to a rare mutation resulting in a hemoglobin M variant. Given this new information, hematology recommended supportive care as well as further testing to confirm the diagnosis of congenital methemoglobinopathy. Whole genome sequencing revealed a likely pathogenic variation in hemoglobin. The neonate was discharged home at 2 weeks of age on full oral feeds with 0.25 L/min nasal cannula as respiratory support, with close outpatient follow-up. By 5 weeks of age, he was weaned off respiratory support.

Conclusion

Congenital methemoglobinemia should be considered in the differential diagnosis for newborns with persistent hypoxemia despite normal imaging and laboratory values. Accurate quantification of methemoglobin concentrations is challenging in neonates due to the presence of other substances that absorb light at similar wavelengths, including HbF, bilirubin, and lipids.

Potential Mechanisms Involved in Chronic Kidney Disease of Unclear Etiology

BACKGROUND AND OBJECTIVES

The etiology of chronic kidney disease of unclear etiology, also known as Mesoamerican nephropathy, remains unclear. We investigated potential etiologies for Mesoamerican nephropathy in an immigrant dialysis population.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

Migrants with Mesoamerican nephropathy kidney failure (n=52) were identified by exclusion of known causes of kidney disease and compared using a cross-sectional survey with demographically similar patients with kidney failure from other causes (n=63) and age/sex/place of origin-matched healthy participants (n=16). Survey results were extended to the bench; C57BL/6 mice (n=73) received 10-15 weekly intraperitoneal injections of paraquat (a reactive oxygen species-generating herbicide) or vehicle. Kidney function, histology, and expression of organic cation transporter-2 (proximal tubule entry for paraquat) and multidrug and toxin extrusion 1 (extrusion pathway) were examined. Kidney biopsies from Nicaraguan patients with acute Mesoamerican nephropathy were stained for the above transporters and compared with patients with tubulointerstitial nephritis and without Mesoamerican nephropathy.

RESULTS

Patients with Mesoamerican nephropathy and kidney failure were young agricultural workers, almost exclusively men; the majority were from Mexico and El Salvador; and they had prior exposures to agrochemicals, including paraquat (27%). After adjustment for age/sex, exposure to any agrochemical or paraquat was associated with Mesoamerican nephropathy kidney failure (odds ratio, 4.86; 95% confidence interval, 1.82 to 12.96; P=0.002 and odds ratio, 12.25; 95% confidence interval, 1.51 to 99.36; P=0.02, respectively). Adjusted for age/sex and other covariates, 1 year of agrochemical exposure was associated with Mesoamerican nephropathy kidney failure (odds ratio, 1.23; 95% confidence interval, 1.04 to 1.44; P=0.02). Compared with 16 matched healthy controls, Mesoamerican nephropathy kidney failure was significantly associated with exposure to paraquat and agrochemicals. Paraquat-treated male mice developed kidney failure and tubulointerstitial nephritis consistent with Mesoamerican nephropathy. Organic cation transporter-2 expression was higher in male kidneys versus female kidneys. Paraquat treatment increased organic cation transporter-2 expression and decreased multidrug and toxin extrusion 1 expression in male kidneys; similar results were observed in the kidneys of Nicaraguan patients with Mesoamerican nephropathy.

CONCLUSIONS

Exposure to agrochemicals is associated with Mesoamerican nephropathy, and chronic exposure of mice to paraquat, a prototypical oxidant, induced kidney failure similar to Mesoamerican nephropathy.

A Retrospective Case-Series of Patient-Reported Response to Ultrasound-Guided Corticosteroid Injection of the Long Head of Biceps Tendon in Orthopedic Surgery

Objective: Identify factors predictive of therapeutic success following ultrasound-guided sheath injection of the long head of the biceps tendon. Materials and Methods: A total of 162 cases were divided into three groups based on clinical responses: complete, partial, or no relief. The presence or absence of clinical symptoms, glenohumeral joint structural pathology, and treatment method was compared. Results: Of the 115 injections with follow-up, 19.1% reported no clinical response while 53.0% had a complete response. Patients with fibromyalgia or chronic spine pain were strongly associated with a poor outcome (odds ratio [OR] = 5.7, P < .001). Conclusion: Ultrasound-guided intra-sheath injection is an effective method of non-surgical management for biceps tendinopathy.

A global ensemble of ocean wave climate statistics from contemporary wave reanalysis and hindcasts

There are numerous global ocean wave reanalysis and hindcast products currently being distributed and used across different scientific fields. However, there is not a consistent dataset that can sample across all existing products based on a standardized framework. Here, we present and describe the first coordinated multi-product ensemble of present-day global wave fields available to date. This dataset, produced through the Coordinated Ocean Wave Climate Project (COWCLIP) phase 2, includes general and extreme statistics of significant wave height (H_s), mean wave period (T_m) and mean wave direction (θ_m) computed across 1980–2014, at different frequency resolutions (monthly, seasonally, and annually). This coordinated global ensemble has been derived from fourteen state-of-the-science global wave products obtained from different atmospheric reanalysis forcing and downscaling methods. This data set has been processed, under a specific framework for consistency and quality, following standard Data Reference Syntax, Directory Structures and Metadata specifications. This new comprehensive dataset provides support to future broad-scale analysis of historical wave climatology and variability as well as coastal risk and vulnerability assessments across offshore and coastal engineering applications.

Measurement(s)	Significant wave height • Mean wave period • Mean wave direction
Technology Type(s)	Global wave reanalysis and hindcasts
Sample Characteristic - Environment	Wind-waves
Sample Characteristic - Location	Global

Risk factors for nonunion following tibiotalocalcaneal arthrodesis: A systematic review and meta-analysis

BACKGROUND

The goal of this study is to review the literature to identify risk factors for nonunion after tibiotalocalcaneal arthrodesis (TTCA) and stratify them based on strength of evidence.

METHODS

Five databases were searched from inception to May 17th, 2020. Abstracts and full-text articles were screened for those that included risk factors predictive of nonunion following TTCA.

RESULTS

Eight studies involving 624 patients were included and 33 potential risk factors for nonunion were identified. Strong evidence supported prior peripheral neuropathic conditions as risk factors for nonunion following surgery (OR: 2.86, 95% CI: 1.56-5.23).

CONCLUSION

TTCA is an effective salvage procedure but is associated with high nonunion rates. The results of our meta-analysis suggest that prior peripheral neuropathic conditions have strong evidence for failure to achieve union. Surgeons should be cognizant of these risks when performing TTCA and carefully monitor patients with the aforementioned comorbidity to achieve successful results.

Factors affecting In vitro methane production from cecum contents of White Roman geese

The goal of this research was to gain understanding of in vitro methane (CH4) production from the cecal contents of White Roman geese under various incubation conditions. Five experiments were conducted to ascertain the effects of i) incubation time, ii) pH, iii) the addition of formic acid to the culture media, iv) temperature, and v) the addition of salt to the nutritive liquid. Methane production increased significantly with the supplementation of formic acid in the culture fluid (Experiment III). Additionally, CH4 production Experiment V was higher than that without saline. In contrast, low CH4 production occurred under acidic conditions (pH ≦5.4) and at temperatures higher or lower than typical bird body temperature (43 °C) without formic acid and saline solution in the culture media. Since bird body temperature cannot be controlled easily, approaches such as maintaining cecum fluid at low pH and preventing the formation of formic acid by adjusting the recipes of feeds could be considered for controlling in vivo CH4 production from the intestinal tract digesta of geese.

Trastuzumab deruxtecan in HER2-positive metastatic breast cancer and beyond

INTRODUCTION

Despite the substantial improvements made in human epidermal growth factor receptor 2 (HER2)-targeted therapies since the approval of trastuzumab more than 20 years ago, there is still considerable unmet need in patients with HER2-expressing breast cancer (BC) and other solid tumors. Trastuzumab deruxtecan (T-DXd) is a newer antibody-drug conjugate approved for the treatment of metastatic breast cancer (BC) and gastric cancer (GC) and is under active investigation in other solid tumors, including non-small cell lung cancer, colorectal cancer, and HER2-low tumors.

AREAS COVERED

The current treatment and investigational landscape of HER2-positive and HER2-low metastatic BC (mBC) and the preclinical and clinical trials investigating T-DXd. To identify relevant literature, a search was performed on English-language publications and congress abstracts.

EXPERT OPINION

T-DXd is likely to become the standard of care for second-line treatment of HER2-positive mBC, and it may play a role in the treatment of hormone receptor-positive and triple-negative mBC with HER2-low expression. Because it was recently approved in the United States and Japan to treat HER2-positive metastatic GC, it holds promise for the treatment of other HER2-positive solid tumors, including colorectal cancer, non-small cell lung cancer, and HER2-low BC.

B. infantis EVC001 Is Well-Tolerated and Improves Human Milk Oligosaccharide Utilization in Preterm Infants in the Neonatal Intensive Care Unit

Not all infants carry specialized gut microbes, meaning they cannot digest human milk oligosaccharides and therefore do not receive complete benefits from human milk. B. infantis EVC001 is equipped to convert the full array of complex oligosaccharides into compounds usable by the infant, making it an ideal candidate to stabilize gut function and improve nutrition in preterm infants. A prospective, open-label study design was used to evaluate the tolerability of B. infantis EVC001 and its effects on the fecal microbiota in preterm infants in a Neonatal Intensive Care Unit. Thirty preterm infants <1,500 g and/or <33 weeks gestation at birth were divided into two matched groups, and control infants were enrolled and discharged prior to enrolling EVC001 infants to prevent cross-colonization of B. infantis: (1) fifteen control infants received no EVC001, and (2) fifteen infants received once-daily feedings of B. infantis EVC001 (8.0 x 10⁹ CFU) in MCT oil. Clinical information regarding medications, growth, nutrition, gastrointestinal events, diagnoses, and procedures was collected throughout admission. Infant stool samples were collected at baseline, Study Days 14 and 28, and 34-, 36-, and 38-weeks of gestation. Taxonomic composition of the fecal microbiota, functional microbiota analysis, B. infantis, and human milk oligosaccharides (HMOs) in the stool were determined or quantified using 16S rRNA gene sequencing, metagenomic sequencing, qPCR, and mass spectrometry, respectively. No adverse events or tolerability issues related to EVC001 were reported. Control infants had no detectable levels of B. infantis. EVC001 infants achieved high levels of B. infantis (mean = 9.7 Log10 CFU/μg fecal DNA) by Study Day 14, correlating with less fecal HMOs (ρ = -0.83, P < 0.0001), indicating better HMO utilization in the gut. In this study, B. infantis EVC001 was shown to be safe, well-tolerated, and efficient in colonizing the preterm infant gut and able to increase the abundance of bifidobacteria capable of metabolizing HMOs, resulting in significantly improved utilization of human milk. Clinical Trial Registration: https://clinicaltrials.gov/ct2/show/NCT03939546, identifier: NCT03939546.

Relationship between episodes of unsustained VTs detected early after an ICD implant and subsequent monomorphic VTs causing appropriate therapy

Introduction

Non-sustained ventricular tachycardias (NSVT) are observed frequently among ICD patients with left ventricular dysfunction (LVD).

Purpose

To analyze the relationship between episodes of NSVTs and monomorphic VTs (MVTs) that subsequently cause appropriate therapies.

Methods

416 ICD patients with LVD (LVEF &lt;45%) followed for 41±27 months. ICD programming (detection and therapies) was standardized. NSVT was defined as any VT of ≥5 beats which did not met the detection criteria occurring within the first 6 months after ICD implant. We analyzed 2201 NSVTs (10+7 beats), which occurred in 250 of the 416 patients (Median=2; IQR=0–7). The mean cycle length (CL) of NSVT was 323±32 ms (adjusted per multiple episodes/patient, generalized estimating equation method (GEEM)).

Results

During the follow-up, 1441 MVT occurred in 183 patients. After showing a significant correlation between burden of NSVT and the occurrence of appropriate therapies due to MVT (C coefficient=0.68; p&lt;0.001), we observed that subjects with &gt;5 NSVT presented an excess of adjusted risk: HR=1.97 (95% CI=1.45–2.72); p&lt;0.001. However, the adjusted mean CL of NSVTs was similar in patients with (322±34) vs. without MVT (324±26 ms); p=0.3.

Among patients who presented NSVTs and MVTs (n=145 subjects), we analyzed the relationship between the adjusted mean CL of the NSVTs (n=1288 episodes) and the CL of the first appropriate therapy due to MVT occurring subsequently. We found a significant and positive correlation between the two (r=0.88; p&lt;0.001); the strongest correlation was observed in subjects with &gt;5 NSVTs (r=0.97, n=52)). The robustness of such correlation was similar in individuals with ischemic (r=0.86; n=91) versus non-ischemic cardiomyopathy (r=0.90; n=54), and in primary (r=0.86; n=75) versus secondary prevention (r=0.90; n=70). The agreement between the CL of first MVT and the adjusted mean CL of NSVT episodes (GEEM) was determined according to the Bland-Altman Method. The difference between the two values was 2±8.3 ms, with only 7.6% (11/145) of patients in whom the difference between the two CL was outside the concordance limits. The agreement was greater, again, in individuals with &gt;5 NSVTs. As shown in the Figure, in more than 95% of patients both values were within the interval of agreement (0.32±4 ms).

Conclusions

1-The burden of NSVTs occurring early after an ICD implant, but not their CL, is associated with a higher incidence of appropriate therapies due to MVT at follow-up.

2-The CL of the NSVTs and that of the first and subsequent MVTs is virtually the same in patients with higher NSVT burden. Therefore, it could be the same tachycardia, but with different duration.

Figure 1

Funding Acknowledgement

Type of funding source: None

An incoherent HIFU transducer for treatment of the medial branch nerve: Numerical study and in vivo validation

BACKGROUND

Chronic back pain due to facet related degenerative changes affects 4-6 million patients a year in the United States. Patients refractory to conservative therapy may warrant targeted injections of steroids into the joint or percutaneous medial branch nerve denervation with radiofrequency ablation. We numerically tested a novel noninvasive high intensity focused ultrasound transducer to optimize nerve ablation near a bone-soft tissue interface.

METHODS

A transducer with 4 elements operating in an incoherent mode was modeled numerically and tested pre-clinically under fluoroscopic guidance. After 6 lumbar medial branch nerve ablations were performed in 2 pigs, they were followed clinically for 1 week and then sacrificed for pathological evaluation.

RESULTS

Simulations show that the acoustic spot size in water at 6 dB was 14mm axial x 1.6mm lateral and 52mm axial x 1.6mm lateral for coherent and incoherent modes, respectively. We measured the size of N = 6 lesions induced in vivo in a pig model and compared them to the size of the simulated thermal dose. The best match between the simulated and measured lesion size was found with a maximum absorption coefficient in the cortical bone adjusted to 30 dB/cm/MHz. This absorption was used to simulate clinical scenarios in humans to generate lesions with no potential side effects at 1000 and 1500 J.

CONCLUSION

The elongated spot obtained with the incoherent mode facilitates the targeting during fluoroscopic-guided medial branch nerve ablation.

Depreciación del caballo Pura Raza Española con la deformación del borde dorsal del cuello

Se plantea como objetivo estimar la depreciación de un caballo Pura Raza Española con la deformación del borde dorsal del cuello. Se estudió a una población de 500 caballos de Pura Raza Española clasificados en 4 edades: Potros (6 meses-4 años), en doma 4-8 años, adultos 8-12 años y maduros (12-20 años), pertenecientes a 65 propietarios, 10 centros de cría Pura Raza Española y un matadero en Andalucía y Extremadura, España. Se realizó la estimación de la depreciación para un año una vez detectada la deformación del borde dorsal de cuello, de manera separada por 3 grupos etarios: caballos en doma 4-8 años, caballos adultos 8-12 años y caballos maduros (12-20 años), mediante tres métodos, el método de línea recta, el método de la reducción de saldo (5%) y el método de la suma de los dígitos de los años. En relación a la depreciación del caballo de Pura Raza Española con deformación del borde dorsal del cuello, estimada para un año, es bastante alta y proporcional al costo del caballo. En conclusión, la depreciación del caballo de Pura Raza Española con la deformación del borde dorsal del cuello, se puede presentar en promedio a partir de los 6 años de edad (aproximadamente entre 4-8 años), la depreciación calculada por los tres métodos línea recta, reducción del saldo al 5% y suma de los dígitos fue similar, solo presento variación por el grupo etario 4-8 años 95%, 8-12 años 99% y 12-20 años 98% de depreciación respetivamente.

P2879Effectiveness of first versus subsequentes ATP attemps: predictors and clinical consequences

Introduction

Antitachycardia pacing (ATP) terminates the majority (but not all) of slow VTs (S-VT) with a cycle length (CL) >320 ms.

Purpose

To analyze the efficacy, safety and predictors of ATP, comparing the first (ATP-1) to the second (ATP-2) and third (ATP-3) attempts.

Methods

We studied 556 S-VT (CL=354±18 ms; range: 321–415 ms; 1.6% syncopes) occurring in 67 patients. ATP programming was standardized, including three consecutive bursts of 15 pulses at 91% of VT CL.

Results

ATP effectiveness declined significantly from ATP-1 (436/556: 78%) compared to ATP-2 (24/103: 23%) and ATP-3 (10/79: 13%), p<0.01 for all comparisons. The percentage of variation of RR intervals (P-RR, %) was significantly higher prior to effective ATP-1 (2.73±1.45 vs 1.23±0.9; p<0.001). After an ineffective ATP-1, the P-RR decreased dramatically, with no differences between episodes terminated or not at ATP-2 (0.6±0.14 vs 0.44±0.16; p=0.6) or ATP-3 (0.54±0.15 vs. 0.52±0.14; p=0.7). The postpacing interval – CL difference (PPI-CLd) after an unsuccessful ATP-1 was shorter in episodes terminating at ATP-2 or ATP-3 (180±24 vs 211±15 ms; p<0.001) being 200 ms the cut-off point with the best sensitivity and specificity for non-effective ATP-2 and ATP-3 (93% and 74%, respectively). By multivariate analysis, the duration of native QRS complex (dQRS) (ms) was found the only independent predictor of a PPI-CLd ≥200 ms (OR=1.04; p=0.003). The best cutoff point of dQRS for PP-CLd ≥200 ms was 120 ms (sensitivity and specificity of 66% and 79%, respectively).

Several predictors of ATP efficacy were found by logistic regression: a) ATP-1: P-RR (OR=7.3; p<0.001), beta-blockers (OR=4.1; p<0.001) and dQRS (OR=0.95; p<0.001); b) ATP-2: PPI-CLd (OR=0.94; p=0.001) and dQRS (OR=0.96; p=0.04); c) ATP-3: PPI-CLd (OR=0.93; p=0.009).

Patients with a dQRS≥120 ms had a lower adjusted effectiveness of ATP and a higher proportion of S-VT causing syncope. Table.

Table 1 Patients with QRS <120 ms Patients with QRS ≥120 ms p value Adjusted effectiveness of ATP-1 89% (82–96) 70% (59–80) 0.008 Adjusted effectiveness of ATP-2 47% (32–63) 23% (11–35) 0.036 Adjusted effectiveness of ATP-3 18% (3–33) 3% (0–6) 0.003 Adjusted incidence of syncope due to S-VT 0.18% (0–0.6) 4.1% (2.1–6.1) 0.025 Values are expressed as mean (95% CI). Generalized Estimating Equations Method.

Conclusions

The efficacy of ATP in terminating S-VT is mainly due to the ATP-1. The regularization of RR intervals after ineffective ATP-1 underlies the lower efficacy of ATP-2 and ATP-3. Since the dQRS correlated significantly with the PPI-CLd, patients with a dQRS≥120 ms had a lower ATP-1, ATP-2 and ATP-3 effectiveness, leading to a higher incidence of syncope.

Biochemical changes in knee articular cartilage of novice half-marathon runners

Objective

To evaluate changes in knee articular cartilage of novice half-marathon runners using magnetic resonance imaging T2 relaxation time mapping.

Methods

Healthy subjects were recruited from local running clubs who met the following inclusion criteria: (i) age 18–45 years; (ii) body mass index less than 30 kg/m²; (iii) had participated in one half-marathon or less (none within the previous 6 months); (iv) run less than 20 km/week; (v) no previous knee injury or surgery; (vi) no knee pain. T2 signals were measured pre- and post-race to evaluate the biochemical changes in articular cartilage after the subjects run a half-marathon.

Results

A significant increase in the mean ± SD T2 relaxation time was seen in the outer region of the medial tibial plateau (50.1 ± 2.4 versus 54.7 ± 2.6) and there was a significant decrease in T2 relaxation time in the lateral femoral condyle central region (50.2 ± 4.5 versus 45.4 ± 2.9). There were no significant changes in the patella, medial femoral condyle and lateral tibia articular surfaces.

Conclusion

An increase in T2 relaxation time occurs in the medial tibial plateau of novice half-marathon runners. This limited region of increased T2 values, when compared with complete medial compartment involvement seen in studies of marathon runners, may represent an association between distance run and changes seen in articular cartilage T2 values.

3325Incidence, outcomes and microbiology in patients with infective endocarditis

Introduction

Despite recent improvements in management, infective endocarditis remains associated with high morbidity and mortality. Over the last few decades, several factors have impacted on both the incidence and outcomes following infective endocarditis.

Purpose

Using a national linkage approach, we describe the changing age- and sex-stratified incidence and outcomes of infective endocarditis in Scotland over the last 25 years.

Methods

We conducted a consecutive retrospective individual patient linkage study across multiple national databases. Using data extracted from the Scottish hospital discharge dataset held by the Information Services Division of NHS National Services Scotland, we extracted episodes for all patients aged 20 years or older who were admitted with infective endocarditis between January 1, 1990, and December 31, 2014 in Scotland, UK. Patient episodes with infective endocarditis were linked to national prescribing and microbiology databases. The primary outcome was 1-year mortality following the index presentation. Generalised additive models were constructed to estimate the crude and age- and sex-stratified incidence rates (using a poison distribution) as well as trends in mortality (using a binomial distribution) adjusted for age, sex and comorbidity.

Results

Across 12,446 individual patients, there were a total of 12,667 hospitalisations (mean age 68±17 years, 55% females) with infective endocarditis using a 5-year look back period. The estimated crude rate of hospitalisation increased from 7.38 per 100,000 (95% CI 6.58 to 8.28) in 1990 to 15.09 per 100,000 (95% CI 13.90 to 16.39) in 2014 (p<0.001). Over the period of the study, 31% (3,877/12,667) of people admitted to hospital with infective endocarditis died within one year of admission. Case fatality fell markedly in both men and women from 1990 to 2014 (Figure). Microbiology was status was available for 34% of all hospitalisations with staphylococcus cultures associated with worse outcomes.

Conclusions

Despite the crude incidence of infective endocarditis doubling over the last 25 years and case fatality remaining high, the risk of death has markedly fallen over the last two decades. Staphylococcus cultures remain an independent marker of poor prognosis in this cohort.

Acknowledgement/Funding

British Heart Foundation

Scale Thickness Predicts Skin Puncture-Force Resistance in Three Pleuronectiform Fishes

In fishes, the skin and scales provide a physical barrier to the external environment and must withstand direct physical insult from biotic and abiotic features of the habitat. Flatfishes likely rely heavily on their scales for physical defense because they rest directly on the substrate. Using a flatfish model, we asked: what are the effects of scale type and scale morphology on puncture force resistance? We also asked: are there morphological and functional differences between the eyed and blind sides in flatfishes and do the morphological and functional properties of scales vary with organism size? Using a large size range of three species of Pleuronectid flatfish (Isopsetta isolepis, n = 10; Parophrys vetulus, n = 10; and Platichthys stellatus, n = 12), we measured the force required to puncture the integument using a sample of skin+scales taken from the eyed and blind side of each individual. We also measured the diameter, area, and thickness of the scales of each individual. Scaling relationships (body length vs. variable of interest) were derived for each species and compared with a priori expectations of geometric similarity. We found no relationship between scale type and puncture resistance and no differences in morphological parameters or puncture resistance between the eyed and blind side within a given species. These flatfish species do vary in their ability to withstand puncture forces; however, once scale thickness is taken into account, species differences disappear. Thus, the ability of a flatfish to withstand mechanical insult from puncture-forces varies depending on the thickness of the scale.

Tree root dynamics in montane and sub-alpine mixed forest patches

BACKGROUND AND AIMS

The structure of heterogeneous forests has consequences for their biophysical environment. Variations in the local climate significantly affect tree physiological processes. We hypothesize that forest structure also alters tree root elongation and longevity through temporal and spatial variations in soil temperature and water potential.

METHODS

We installed rhizotrons in paired vegetation communities of closed forest (tree islands) and open patches (canopy gaps), along a soil temperature gradient (elevations of 1400, 1700 and 2000 m) in a heterogeneous mixed forest. We measured the number of growing tree roots, elongation and mortality every month over 4 years.

KEY RESULTS

The results showed that the mean daily root elongation rate (RER) was not correlated with soil water potential but was significantly and positively correlated with soil temperature between 0 and 8 °C only. The RER peaked in spring, and a smaller peak was usually observed in the autumn. Root longevity was dependent on altitude and the season in which roots were initiated, and root diameter was a significant factor explaining much of the variability observed. The finest roots usually grew faster and had a higher risk of mortality in gaps than in closed forest. At 2000 m, the finest roots had a higher risk of mortality compared with the lower altitudes.

CONCLUSIONS

The RER was largely driven by soil temperature and was lower in cold soils. At the treeline, ephemeral fine roots were more numerous, probably in order to compensate for the shorter growing season. Differences in soil climate and root dynamics between gaps and closed forest were marked at 1400 and 1700 m, but not at 2000 m, where canopy cover was more sparse. Therefore, heterogeneous forest structure and situation play a significant role in determining root demography in temperate, montane forests, mostly through impacts on soil temperature.