United States

Background: 
Total Knee Arthroplasty (TKA) is one of the most commonly performed orthopaedic surgeries in the United States, particularly among older adults with comorbid conditions. Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia globally and is frequently observed in patients undergoing TKA. It is known to complicate postoperative outcomes; however, the long-term impact of pre-existing AF on surgical outcomes after TKA remains underexplored. Thus, this study aimed to evaluate 2-, 5-, and 10-year risk and indications for revision among patients with AF undergoing TKA.
Methods: 
The TriNetX database was utilized for this retrospective cohort study. The primary outcome was the 2-, 5-, and 10-year risk of revision following primary TKA among patients with and without pre-existing AF. The AF and control cohorts were 1:1 propensity matched by age, sex, clinical comorbidities and anticoagulant use. Cox proportional hazards models were used to assess the risk of all-cause revision as well as specific complications. Results were reported as hazard ratios (HRs) and confidence intervals (CI). A p-value of 0.05 was deemed to be the level of significance. 
Results: 
Patients with pre-existing AF (n=22,510) had a significantly higher risk of all-cause revision at 2 years (HR 1.3, 95% CI 1.1–1.5, p&lt;0.001), 5 years (HR 1.2, 95% CI 1.1–1.3, p&lt;0.001), and 10 years (HR 1.2, 95% CI 1.1–1.3, p&lt;0.001) post-TKA compared to matched controls (n=22,510). The AF cohort demonstrated increased risk of periprosthetic joint infection (PJI) (HR 1.5, 95% CI 1.4-1.7, p&lt;0.001) and hematoma (HR 1.8, 95% CI 1.6-2, p&lt;0.001) while showing decreased incidence of arthrofibrosis (HR 0.9, 95% CI 0.8-0.9, p=0.003). No significant difference in periprosthetic fracture rates was observed.
Conclusion: 
Pre-existing AF is associated with increased long-term risk of revision following TKA. These findings suggest the need for enhanced longitudinal monitoring and multidisciplinary perioperative management, including a lower clinical threshold for PJI evaluation and vigilant supervision of anticoagulation therapy.


AMA Research Challenge 2025 

Impact of Pre-existing Atrial Fibrillation on Long-Term Outcomes Following Total Knee Arthroplasty

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AMA Research Challenge 2024 

Join the AMA Research Challenge poster symposium and semifinals to explore top research posters and score posters in the semifinals (an AMA member exclusive opportunity).

Background: 
Total Knee Arthroplasty (TKA) is one of the most commonly performed orthopaedic surgeries in the United States, particularly among older adults with comorbid conditions. Atrial fibrillation (AF) is the most prevalent cardiac arrhythmia globally and is frequently observed in patients undergoing TKA. It is known to complicate postoperative outcomes; however, the long-term impact of pre-existing AF on surgical outcomes after TKA remains underexplored. Thus, this study aimed to evaluate 2-, 5-, and 10-year risk and indications for revision among patients with AF undergoing TKA.
Methods: 
The TriNetX database was utilized for this retrospective cohort study. The primary outcome was the 2-, 5-, and 10-year risk of revision following primary TKA among patients with and without pre-existing AF. The AF and control cohorts were 1:1 propensity matched by age, sex, clinical comorbidities and anticoagulant use. Cox proportional hazards models were used to assess the risk of all-cause revision as well as specific complications. Results were reported as hazard ratios (HRs) and confidence intervals (CI). A p-value of 0.05 was deemed to be the level of significance. 
Results: 
Patients with pre-existing AF (n=22,510) had a significantly higher risk of all-cause revision at 2 years (HR 1.3, 95% CI 1.1–1.5, p<0.001), 5 years (HR 1.2, 95% CI 1.1–1.3, p<0.001), and 10 years (HR 1.2, 95% CI 1.1–1.3, p<0.001) post-TKA compared to matched controls (n=22,510). The AF cohort demonstrated increased risk of periprosthetic joint infection (PJI) (HR 1.5, 95% CI 1.4-1.7, p<0.001) and hematoma (HR 1.8, 95% CI 1.6-2, p<0.001) while showing decreased incidence of arthrofibrosis (HR 0.9, 95% CI 0.8-0.9, p=0.003). No significant difference in periprosthetic fracture rates was observed.
Conclusion: 
Pre-existing AF is associated with increased long-term risk of revision following TKA. These findings suggest the need for enhanced longitudinal monitoring and multidisciplinary perioperative management, including a lower clinical threshold for PJI evaluation and vigilant supervision of anticoagulation therapy.


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Background:

Enhanced Recovery After Surgery (ERAS) is a multimodal, evidence-based perioperative care protocol designed to reduce surgical stress, improve postoperative recovery, and minimize hospital stay and complications. Since its development in the early 2000s by the ERAS Society, this protocol has shown consistent success across various surgical specialties. Anesthesiologists play a pivotal role in the planning and execution of ERAS pathways, influencing outcomes across the preoperative, intraoperative, and postoperative phases.

Aims:

The aim is to evaluate whether or not ERAS implementation leads to shorter hospital stays, reduced postoperative pain and opioid use, faster return of bowel function, decreased complications and readmissions, and greater patient satisfaction.

Methods:

Following PRISMA guidelines, a systematic search of PubMed was conducted for English-language studies from January 2015 to June 2025. A systematic review was performed that highlights the role of anesthesia within the ERAS framework using literature sourced from peer-reviewed publications and ERAS Society guidelines. The protocol elements were categorized into three phases: preoperative, intraoperative, and postoperative. Special attention was given to pharmacologic interventions, anesthetic regimens, and perioperative fluid and pain management, aligning with the responsibilities of anesthesiologists. Key preoperative components include patient education, optimization of comorbidities, one-month abstinence from smoking and alcohol, premedication with NSAIDs/PCM, and carbohydrate loading. Intraoperative strategies include using balanced fluid therapy,
short-acting anesthetics, a mix of pain relief methods, and laparoscopic techniques when possible. Postoperative care emphasizes early mobilization, hydration, nausea control, and techniques such as chewing gum to reduce ileus.

Results:

Preoperative Components: Key elements include thorough risk assessment, patient education, smoking and alcohol abstinence for at least one month, deep vein thrombosis (DVT) prophylaxis, premedication with NSAIDs or dexamethasone, and carbohydrate loading. Mechanical bowel preparation and minimized fasting (solid food up to 6 hours, clear carbohydrate-rich liquids up to 2 hours before
surgery) are also essential.Intraoperative Components: A single antibiotic dose is recommended. Fluid management involves zero-balance therapy for low-risk patients and goal-directed fluid therapy for high-risk surgeries to avoid both hypovolemia and fluid overload. Minimally invasive techniques like laparoscopy are preferred. Anaesthetic strategies favor short-acting agents and regional anesthesia. Vigilant prevention of hypothermia and avoidance of nasogastric tubes and drains are encouraged. Postoperative Components: Early ambulation, prompt catheter removal, hydration, and non-pharmacologic interventions like chewing gum help minimize ileus and speed recovery. Implementation of ERAS protocols, particularly when guided by anesthesiologists, has demonstrated significant benefits:
● Reduced postoperative pain and opioid requirement
● Earlier return of bowel function
● Decreased complication and readmission rates
● Shorter hospital stay and improved patient satisfaction

Conclusion:

ERAS protocols represent a paradigm shift in perioperative care, reducing postoperative morbidity and length of stay. Anaesthesiologists play a central role across all ERAS phases—from risk stratification and fasting minimization to optimized anaesthesia, multimodal analgesia, and early recovery facilitation. This structured review highlights the multidisciplinary nature of ERAS and reinforces the anaesthesiologist’s role as a key driver of successful outcomes.

Enhanced Recovery After Surgery (ERAS): An Anesthesiologist’s Perspective

Introduction:
Left ventricular free-wall rupture (LVFWR) is a rare but catastrophic complication of acute myocardial infarction (AMI), occurring in only ~0.01% of ST-segment elevation AMI cases and carrying an in-hospital mortality approaching 80%, even with surgery. Prompt recognition and rapid multidisciplinary management are crucial, with anesthesiologists playing a central role in stabilization, transfusion, and coordination of care.

Case Presentation:
A 79-year-old male with no prior cardiac history presented with nausea, vomiting, and hypotension. ECG revealed diffuse ST-segment elevations with PR depression, and laboratory evaluation showed markedly elevated troponins (>20,000 ng/L). Bedside echocardiography demonstrated regional wall motion abnormalities and a moderate pericardial effusion. Cardiac catheterization confirmed acute circumflex thrombosis complicated by LVFWR. During catheterization, the patient suffered cardiac arrest requiring 25 minutes of advanced cardiac life support before extracorporeal membrane oxygenation (ECMO) was initiated.

In the operating room, intraoperative transesophageal echocardiography (TEE) revealed biventricular tamponade. Emergent sternotomy evacuated the pericardial effusion, revealing a 5 cm lateral wall rupture. Attempts at repair with sutures, pledgets, BioGlue, and Nu-Knit were complicated by poor tissue integrity and recurrent rupture. After ~100 minutes of cardiopulmonary bypass, the patient was transitioned to VA-ECMO with left ventricular venting. Despite massive transfusion, vasopressor support, and open chest management, the patient remained profoundly unstable and expired in the CICU shortly after surgery.

Conclusion:
This case underscores the anesthetic challenges of LVFWR, particularly rapid hemodynamic collapse, need for massive transfusion, and coordination with surgical teams. Early suspicion, expedited imaging, and immediate anesthetic intervention—including invasive monitoring, pharmacologic optimization, and ECMO initiation—are critical to survival, though tissue friability and recurrent rupture often limit outcomes. Proactive multidisciplinary strategies remain essential in managing this rare but devastating complication.

Medically Challenging Case: Anesthetic Management of Post-Infarction Left Ventricular Free-Wall Rupture

Background:
Gastric antral vascular ectasia (GAVE), also known as watermelon stomach, accounts for up to 4% of non-variceal upper gastrointestinal bleeding. It is often associated with cirrhosis and autoimmune disorders but rarely occurs in patients with alpha-1 antitrypsin deficiency (AATD), particularly in the absence of cirrhosis. Accurate diagnosis is crucial, as GAVE does not respond to therapies for portal hypertension.
Case Presentation:
A 64-year-old Caucasian woman with a history of AATD-related emphysema and chronic anemia presented with worsening fatigue and exertional dyspnea. She also reported diffuse abdominal pain with intermittent nausea and vomiting, but no hematemesis. Laboratory studies revealed normocytic anemia (hemoglobin 8.8 g/dL) and biochemical markers consistent with iron deficiency (ferritin 26 ng/mL, transferrin saturation 10%), with normal B12 and folate levels. Liver enzymes were mildly elevated. Liver biopsy showed severe steatosis, steatohepatitis (grade 2), stage 2 fibrosis (Brunt classification), and PAS-positive periportal globules consistent with AATD, but no evidence of cirrhosis. Upper endoscopy revealed moderate gastric antral vascular ectasia with bleeding in the gastric antrum. Argon plasma coagulation (APC) was performed with successful hemostasis.
Discussion:
Although GAVE is most commonly associated with cirrhosis, its occurrence in non-cirrhotic patients with systemic or autoimmune conditions suggests alternative pathogenic pathways. This case highlights a rare association between GAVE and alpha-1 antitrypsin deficiency (AATD) in the absence of cirrhosis. AATD causes systemic inflammation and accumulation of misfolded proteins in the liver, which may trigger immune-mediated processes that lead to vascular ectasia. Recognition of GAVE in such patients is critical, as it often presents with chronic iron-deficiency anemia and may be misattributed to more common causes. Clinical manifestations vary significantly, ranging from asymptomatic occult blood loss to overt gastrointestinal bleeding.
Due to the similar clinical presentation—and the fact that GAVE does not respond to therapies aimed at reducing portal venous pressure—it is imperative to distinguish it from portal hypertensive gastropathy via endoscopic evaluation. Endoscopic therapy, particularly APC, remains the primary treatment and is effective for bleeding control. Clinicians should maintain a high index of suspicion for GAVE in patients with unexplained anemia and systemic conditions like AATD. Early diagnosis and targeted intervention can prevent ongoing blood loss and improve patient outcomes.


Watermelon Stomach in Non-Cirrhotic Alpha-1 Antitrypsin Deficiency: A Rare Cause of Chronic Anemia

Background
Pelvimetry, the radiographic assessment of pelvic dimensions, is instrumental in assessing pelvic architecture and guiding obstetric planning in high-risk pregnancies, particularly those involving complex anomalies such as conjoined twins. This vignette presents a rare case of omphalothoracopagus (omphalo- = belly button, thoraco- = chest, -pagus = conjoined) twins diagnosed at 20 weeks gestation in a G1P0 23-year-old woman, utilizing advanced modalities including 3D ultrasound, Pulsed Wave Doppler, and Maximum Intensity Projection (MIP). Imaging revealed shared vital structures—a single liver and a six-chambered heart—highlighting the anatomical constraints and surgical limitations. Given the extent of fusion and lack of viable separation options, the pregnancy was terminated. This case highlights the role of pelvimetry and high-resolution imaging in prenatal diagnosis, multidisciplinary planning, and outcome optimization.
Case Presentation
A G1P0 23-year-old woman was referred at 20 weeks’ gestation for evaluation of suspected conjoined twins. Diagnostic imaging included 2D, 3D, and 4D ultrasound, color flow Doppler, Pulsed Wave Doppler, and Maximum Intensity Projection (MIP), performed using a Voluson 730 ultrasound system. These revealed omphalothoracopagus twins sharing a single liver and a complex six-chambered heart. Further confirmation via MRI showed thoracic fusion and a shared upper abdominal cavity. Pelvimetry via advanced ultrasound techniques enabled visualization of maternal pelvic anatomy and fetal position. Despite the detailed imaging, the severity of anatomical fusion precluded surgical separation. The patient elected for pregnancy termination, and post-mortem findings confirmed the prenatal diagnosis.
Discussion
Despite the decision to terminate the pregnancy due to severe anomalies, pelvimetry proved essential. Using a Voluson 730 ultrasound system, the team employed 2D color flow mapping, pulsed wave Doppler, 3D/4D reconstruction, maximum intensity projection (MIP), and tomographic imaging to assess pelvic dimensions and the spatial relationship of the twins’ shared organs.
Pelvimetry played a vital role in evaluating maternal anatomy and guiding the clinical team’s assessment of surgical feasibility. In conjoined twin cases—especially those involving shared vital structures—accurate pelvic and fetal imaging is key to delivery planning and supports informed, multidisciplinary decision-making.
The value of pelvimetry extends beyond rare or complex cases; it is also instrumental in preventing emergency cesarean sections and reducing the risk of traumatic births for both mother and baby. These imaging techniques offer critical insights to minimize maternal and fetal risk, improve diagnostic precision, and enhance overall clinical outcomes and the birthing experience.

The Role of Pelvimetry in the Delivery of Omphalothoracopagus Conjoined Twins

Background
Pseudohypoparathyroidism type 1b is a rare genetic condition generally affecting young-to-middle-aged adults that arises from abnormal cAMP response to parathyroid hormone (PTH), resulting in resistance to stimulation of renal PTH receptors. PTH resistance leads to a pattern of hypocalcemia, hyperphosphatemia, and secondarily elevated PTH. These abnormalities can result in secondary Fahr syndrome, neurologic sequela of pseudohypoparathyroidism consisting of predominant parkinsonism, occurring from characteristic basal ganglia calcifications.

Case Presentation
The patient, a 9-year-old male with no significant past medical history or family history, presented to the Emergency Department with one day of acutely worsening mental status and difficulty walking, in the setting of gradual-onset behavioral changes and abnormal coordination over the past three months, with no preceding trauma. During this interval, he had been treated for suspected Lyme disease without clinical improvement. Head CT without contrast was ordered and showed calcifications in the basal ganglia, thalamus, and the gray-white matter junction of the cerebral cortex. Subsequent labs revealed serum calcium of 4.9, phosphorous of 10.1, and PTH of 292. The patient was also later found to have vertebral compression fractures on spinal radiography. Initial treatment consisted of calcium repletion with IV calcium gluconate until total calcium >7.5, then PO calcium carbonate. He additionally received supplemental calcitriol and vitamin D3, reduced phosphorous diet, and physical therapy. He ultimately recovered his ability to walk, and his mental status returned to baseline.

Discussion
This rare condition has been reported in adults and even some children as young as age 12, but this case represents one of the youngest documented patients with pseudohypoparathyroidism type 1b with secondary Fahr syndrome to date. Prompt recognition of this disorder in children is essential to avoid delays in diagnosis and treatment. In the presented case, CT of the head without contrast and labs were ordered in a timely manner, allowing for efficient identification of the characteristic diagnostic features of pseudohypoparathyroidism type 1b, followed by targeted treatment. The case therefore underscores the utility of head CT without contrast as an initial evaluation of children presenting with parkinsonian symptoms, given the distinctive findings of basal ganglia calcifications in pseudohypoparathyroidism that can be rapidly visualized, and then confirmation of the diagnosis with follow-up lab studies including calcium, phosphorous, and PTH. Furthermore, the patient in this case had quick resolution of symptoms with initiation of appropriate treatment, so efficient diagnosis evidently yields desirable clinical outcomes for this condition.

A pediatric patient with pseudohypoparathyroidism type 1b with secondary Fahr syndrome

Background
Left Without Being Seen (LWBS) remains a critical quality and safety metric in emergency medicine. Patients who LWBS face increased risk of clinical deterioration and reflect system-level inefficiencies. Traditional methods to identify LWBS risk are retrospective, limiting the opportunity for proactive mitigation. This study developed and compared predictive models using triage-time variables to identify patients at elevated risk for LWBS across a CDC national dataset.

Methods
We analyzed data from the National Hospital Ambulatory Medical Care Survey (NHAMCS), combining emergency department visits from 2015 to 2022. Predictor variables included arrival hour (as decimal time), day of week, triage acuity, age, race/ethnicity, insurance status, and gender. The outcome variable was binary LWBS status. Records with missing key variables were excluded, and class imbalance was addressed via synthetic oversampling and weighted modeling. We trained logistic regression, random forest, and XGBoost classifiers with cross-validated grid tuning and adaptive racing for hyperparameter optimization. A model stacking approach was subsequently employed to combine predictions from all three base models into a unified ensemble using a meta-learner trained to optimize classification metrics. Performance was assessed by positive predictive value (PPV), negative predictive value (NPV), sensitivity, specificity, F1 score, and area under the precision-recall curve (AUC-PR), with optimal thresholds selected via post hoc analysis.

Results
LWBS prevalence was low across all years (~1%). Individually, base models showed high NPV and specificity but struggled with sensitivity due to class imbalance. While XGBoost marginally outperformed others in positive class detection, the stacked ensemble demonstrated improved harmonic balance across PPV, NPV, sensitivity, and specificity. The stacking framework yielded more stable and clinically interpretable predictions, mitigating trade-offs observed in the base models. Variables most associated with increased LWBS risk included early-morning arrival times, lower acuity levels, and uninsured status.

Conclusion
Machine learning models using routinely collected emergency department triage data can predict LWBS risk with moderate precision despite low prevalence. Stacked ensemble modeling enhanced predictive performance over individual models, offering a more balanced approach which is critical for identifying at-risk patients without over-alerting. While recall remains limited, implementing these models for real-time flagging could enable targeted interventions to reduce LWBS rates and improve patient safety. Future work will explore integration into live ED workflows with decision support alerts and the inclusion of operational variables such as wait times and staffing levels to enhance predictive performance.

Know Before They Go: Predicting LWBS Risk in the Emergency Department with Machine Learning

Medical students' perceptions and assumptions about patients with disability: A case-based approach

One in four adults in the United States has a disability. Mobility impairments are most common, impacting 14% of Americans. Persons with disabilities (PWD), including those with mobility impairments, consistently receive less preventive care and subsequently have poorer health outcomes. Key drivers include provider attitudes, knowledge, lack of training, and low awareness. Our objective was to assess whether medical students’ perceptions of PWD influence their clinical recommendations. 

An anonymous survey was administered to medical students at Michigan State University College of Human Medicine. Respondents were asked to review a clinical case and then answer multiple-choice and free-response questions regarding their management decisions for acute low back pain and hypertension. Respondents were randomly assigned a case involving a patient with or without a mobility disability. The disability was a lower limb amputation described in the patient’s medical history and physical exam. Descriptive statistics and frequency tables were used to describe the key quantitative and qualitative variables. 

There were 118 responses across four years (e.g., M1, M2, M3, and M4). Demographic data collected included year in medical school, race, gender, whether the respondent identified as a PWD, or if they had a family member with mobility issues. Overall, respondent demographics and their familiarity with PWDs were proportionately distributed between cases. Respondent decision-making differed between cases. Notably, the PWD case respondents included inaccurate, scientifically unsound assumptions. For example, one respondent’s rationale for prioritizing “Smoking Cessation” was that “Hypertension already caused amputation, likely severe, and smoking cessation [is] necessary to prevent thromboembolism.” Further analysis showed that respondents with the PWD case frequently incorrectly inferred opioid use or limited ability to exercise due to amputation. While clinical rationale differed, there was no statistically significant difference in respondents' beliefs in the patient's adherence to treatment. 

This is the first study using case methodology to see if medical students’ perceptions of PWDs are linked to clinical decision-making. Overall, the data imply that biases may lead to sub-optimal care and health disparities for PWDs. Moving forward, medical schools should consider curricula that show how bias, stigma, and misconceptions about disability affect patient care to address this issue. We are currently assessing family medicine residents and attending physicians across Michigan to expand our understanding of factors that lead to patient disparities. Ideally, this research, in addition to data on the lived experiences of PWDs, can be used to create evidence-based solutions to improve care and outcomes.

Medical students' perceptions and assumptions about patients with disability: A case-based approach

Patients with end-stage heart failure remain dependent on heart transplant as the primary treatment. One of the limiting factors that remains in organ donation is the availability of suitable donors, making the use of each organ donation crucial. Cardiac structural malformations can interfere with graft suitability if not identified preoperatively, particularly in cases of atrial septal defects such as patent foramen ovale (PFO). Currently, Transthoracic echocardiography (TTE) is the standard imaging modality to evaluate the donor hearts due to its accessibility and non-invasive nature. Its diagnostic accuracy for detecting certain structural defects in the complex donor population is poorly defined. Recent prospective studies suggest that a significant diagnostic gap exists, as intraoperative findings often reveal defects that TTE misses. This highlights the urgent need to critically evaluate current screening practices. 

A single-center, prospective, observational study was conducted between April 2024 and April 2025. To systematically assess the frequency, characteristics, and detection rates of structural cardiac defects in donor hearts. Inclusion criteria encompassed all donor hearts or heart-lung blocks implanted in adult recipients; where structural defects were identified and comprehensive pre- and intraoperative data were available.

During the study period, a total of 102 heart transplants were performed, of which 15 cases (14.7%) had structural cardiac abnormalities identified intraoperatively. The vast majority of these defects (n = 14, 93%) were patent foramen ovale (PFO), while one case involved an anomalous origin of a coronary artery. The anomalous coronary case was diagnosed preoperatively and excluded from further analysis. All 4 cases with three or more high-risk features demonstrated atrial septal abnormalities detectable by TTE, suggesting that increased anatomical complexity may influence the likelihood of defect visualization despite the overall low sensitivity of TTE in this population.

The inadequate identification of structural cardiac anomalies, especially PFO, during the assessment of donor hearts constitutes a significant obstacle to enhancing organ utilization and transplant success rates. Although transthoracic echocardiography serves as a crucial tool for detecting abnormalities, its restricted sensitivity limits its efficacy as the exclusive screening technique in the intricate donor cohort. This investigation underscores the necessity for improved diagnostic methodologies, encompassing the incorporation of transesophageal echocardiography, contrast-enhanced imaging, and standardized procurement protocols to advance the detection of clinically pertinent defects. Such initiatives could mitigate intraoperative unforeseen events, enable prompt surgical interventions, and optimize the safe application of available donor hearts.

Detection of Cardiac Malformations in Donor Hearts: Evaluating Preoperative Screening Accuracy.

Introduction
Climate change is causing heatwaves to become more frequent, intense, and prolonged, posing severe health risks to farmworkers, who are disproportionately affected by extreme weather. Farmworkers face an occupational heat-related mortality rate 35 times higher than workers in other industries, underscoring the danger they face. This risk is compounded by inadequate training, limited workplace safety regulations, physically demanding labor, and poor access to water, shade, and breaks. This cross-sectional survey aimed to assess the prevalence of farmworkers working during perceived unsafe climate conditions and access to employer-provided safety training.

Methods
This survey was administered during a health education event in Oxnard, California. Participants were recruited in-person and completed the survey digitally in English or Spanish. Participation was voluntary and anonymous, with respondents compensated via grocery gift cards. This study was considered exempt from IRB review by the University of California, Los Angeles. Variables collected included demographics, health insurance, climate-related work conditions, and access to training, and employer protections. Descriptive statistics were used for analysis.

Results
A total of 46 farmworkers completed the survey; 96% responded in Spanish. Most participants were female (60.0%) and in the 45–54 age range (31.1%). The majority (77.8%) worked in crop farming, and 62.2% were employed by farm labor contractors. Nearly half (43.8%) reported having no health insurance, and only 6.2% had employer-sponsored coverage. One in five reported that their health had been harmed by work, yet over half (56.8%) did not report injuries. Of those who did not report their injuries, 28.6% cited not knowing how to report an issue. Although half (58.1%) worked in extreme heat and 34.9% in wildfire smoke, 30.2% reported not having received training on heat-illness prevention and 79.1% did not receive training on climate-related risks beyond heat. Access to paid sick leave was low (30.2%), and 39.5% were unaware of such benefits.

Conclusion
This study identifies critical gaps in climate-related workplace protections for California farmworkers. Despite regulations, many continue to work in unsafe conditions without adequate training regarding occupational health hazards or knowledge of their rights. These findings highlight the need for stronger enforcement of safety standards, employer accountability, and culturally appropriate education for workers. Policy efforts must prioritize worker-centered solutions that promote safety in the face of intensifying climate risks.


Gaps in Climate Health Protections for California Farmworkers: A Cross-Sectional Survey of Workplace Protections and Perceived Safety

Background: Since emergence of COVID-19, and its association with myocarditis, the use of troponin I (TnI) tests has drastically increased at pediatric ERs. We hypothesize that in pediatric patients presenting to the ER, the natural history of trivially elevated troponin is normal without cardiac disease. Additionally, we hypothesized there exists a cut-off troponin value with good sensitivity and specificity.

Methods: We conducted a single-center retrospective study of patients who were presented to our ER 2022-2023 found to have elevated troponin levels (hospital assay defines abnormal > 0.021 ng/mL) and the following chief complaints: chest pain, dizziness, syncope/near-syncope, fatigue, shortness of breath, and palpitations. Patients without elevated troponin or follow-up cardiac testing (echocardiogram, ECG) were excluded. Patients with a prior history of cardiac disease were excluded. We compared patients found to have no cardiac disease with those who did. Cardiac disease was defined as an abnormality on ECG, echo, or MRI (if available). Comparisons were made using chi-square and independent t-tests. Receiver operating curve (ROC) analysis to determine discriminatory ability of troponin. 

Results: In total, 275 patients met inclusion criteria for chief complaint and elevated troponin, though 103 had incomplete cardiac testing, leaving 172 patients for analysis. Of these, 29 (17%) were diagnosed with cardiac disease and 143 (83%) without cardiac disease (Table). There was a lesser incidence of female sex in the cardiac disease group. Those with cardiac disease had a significantly greater troponin value at presentation (10.0 +/- 12.1 vs. 0.35 +/- 1.5, p < 0.001). MRI was only available for 17 patients total (10%). ROC analysis demonstrated excellent discriminatory ability for troponin at ER presentation for detection of cardiac disease (Figure, area under curve 0.95, p < 0.001). Youden’s J determined a cut-off troponin value of 0.3 for sensitivity 90% and specificity 86%. There were 47 patients with a troponin > 0.3, and 125 < 0.3. A troponin > 0.3 yields a positive predictive value of 55%, while < 0.3 yields a negative predictive value of 98%. Those with troponin <0.3 were admitted 70% of the time, and >0.3 admitted 83%. 

Conclusions: Troponin level at ER presentation demonstrates good discriminatory ability for subsequent cardiac disease diagnosis. Low troponin levels (< 0.3) have a high negative predictive value, however a significant number of patients were admitted to the hospital. This initial data may guide appropriate triaging and resource utilization. 



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