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Objectives. To assess differences in contextual factors by intent among pediatric firearm injury patients and determine factors associated with data missingness. Methods. We retrospectively queried the American College of Surgeons Firearm Study database (March 1, 2021-February 28, 2022) for patients aged 18 years or younger. We stratified preinjury, firearm-related, and event-related factors by intent and compared them by using Fisher exact, χ2, or 1-way analysis of variance testing. Secondary analysis estimated the adjusted odds of missingness by using generalized linear modeling with binominal logit link. Results. Among 17 395 patients, 2974 (17.1%) were aged 18 years or younger; 1966 (66.1%) were injured by assault, 579 (19.5%) unintentionally, and 76 (2.6%) by self-inflicted means. Most contextual factors differed by intent, including proportion of youths with previous adverse childhood experiences, mental illness, and violent assaults or injury, firearm type and access, perpetrator relationship, and injury location. In adjusted analyses, age, trauma center designation, intent, and admission status were associated with missingness. Conclusions. Contextual factors related to pediatric firearm injury vary by intent. Specific predictors associated with missingness may inform improved future data collection. Public Health Implications. Contextual factors related to pediatric firearm injury can be obtained in a systematic manner nationally to inform targeted interventions. (Am J Public Health. Published online ahead of print August 15, 2024:e1-e13. https://doi.org/10.2105/AJPH.2024.307754).
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Importance: Motor vehicle crash (MVC) and firearm injuries are 2 of the top 3 mechanisms of adult injury-related deaths in the US. Objective: To understand the differing associations between community-level disadvantage and firearm vs MVC injuries to inform mechanism-specific prevention strategies and appropriate postdischarge resource allocation. Design, Setting, and Participants: This multicenter cross-sectional study analyzed prospectively collected data from the American College of Surgeons (ACS) Firearm Study. Included patients were treated either for firearm injury between March 1, 2021, and February 28, 2022, or for MVC-related injuries between January 1 and December 31, 2021, at 1 of 128 participating ACS trauma centers. Exposures: Community distress. Main outcome and Measure: Odds of presenting with a firearm as compared with MVC injury based on levels of community distress, as measured by the Distressed Communities Index (DCI) and categorized in quintiles. Results: A total of 62â¯981 patients were included (mean [SD] age, 42.9 [17.7] years; 42â¯388 male [67.3%]; 17â¯737 Black [28.2%], 9052 Hispanic [14.4%], 36â¯425 White [57.8%]) from 104 trauma centers. By type, there were 53â¯474 patients treated for MVC injuries and 9507 treated for firearm injuries. Patients with firearm injuries were younger (median [IQR] age, 31.0 [24.0-40.0] years vs 41.0 [29.0-58.0] years); more likely to be male (7892 of 9507 [83.0%] vs 34â¯496 of 53â¯474 [64.5%]), identified as Black (5486 of 9507 [57.7%] vs 12â¯251 of 53â¯474 [22.9%]), and Medicaid insured or uninsured (6819 of 9507 [71.7%] vs 21â¯310 of 53â¯474 [39.9%]); and had a higher DCI score (median [IQR] score, 74.0 [53.2-94.8] vs 58.0 [33.0-83.0]) than MVC injured patients. Among admitted patients, the odds of presenting with a firearm injury compared with MVC injury were 1.50 (95% CI, 1.35-1.66) times higher for patients living in the most distressed vs least distressed ZIP codes. After controlling for age, sex, race, ethnicity, and payer type, the DCI components associated with the highest adjusted odds of presenting with a firearm injury were a high housing vacancy rate (OR, 1.11; 95% CI, 1.04-1.19) and high poverty rate (OR, 1.17; 95% CI, 1.10-1.24). Among patients sustaining firearm injuries patients, 4333 (54.3%) received no referrals for postdischarge rehabilitation, home health, or psychosocial services. Conclusions and Relevance: In this cross-sectional study of adults with firearm- and motor vehicle-related injuries, we found that patients from highly distressed communities had higher odds of presenting to a trauma center with a firearm injury as opposed to an MVC injury. With two-thirds of firearm injury survivors treated at trauma centers being discharged without psychosocial services, community-level measures of disadvantage may be useful for allocating postdischarge care resources to patients with the greatest need.
Subject(s)
Accidents, Traffic , Wounds, Gunshot , Humans , Male , Female , Adult , Wounds, Gunshot/epidemiology , Cross-Sectional Studies , Middle Aged , Accidents, Traffic/statistics & numerical data , United States/epidemiology , Prospective Studies , Firearms/statistics & numerical dataABSTRACT
Background: The experiences of trauma patients referred from Ghanaian non-tertiary hospitals for definitive care at higher levels is not well-known. Understanding the motivations of injured patients who do not attend their referral for definitive management may inform interventions to improve injury outcomes. Methods: This study is a follow-up survey of participants of a larger study involving initial management of injured patients presenting to 8 non-tertiary hospitals in Ghana from October 2020 to March 2022. Injured patients referred to higher levels of care were surveyed by phone using a structured questionnaire and patients who could not be reached were excluded. The main outcome was referral non-attendance and differences between patients who attended the referral and those who did not were determined with chi squared tests. Variables with intergroup differences were included in a multivariable logistic regression. Open-ended survey responses were analyzed using thematic content analysis. Results: Of 335 referred patients surveyed, 17 % did not attend the referral. Factors associated with referral non-attendance included being male (Adjusted odds ratio (AOR)=2.70, p = 0.013), sustaining a fracture (AOR=2.83, p = 0.003), and having less severe injury (AOR 2.84, p = 0.017). Primary drivers of referral non-attendance included financial problems (59 %), family influence (45 %), and lack of transportation (20 %). The majority of patients (77 %) not attending the referral sought treatment from traditional healers, citing lower cost, faster service, and a perception of equivalent outcomes. Reported facilitators of referral attendance included positive hospital staff experiences and treatment while barriers included higher hospital costs, lack of bed space, and poor interhospital communication. Conclusions: An important proportion of injured patients in Ghana do not attend referrals for definitive management, with many seeking care from traditional healers. Our study identified possible targets for interventions aimed at maintaining the continuum of hospital-based care for injured patients in order to improve outcomes.
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INTRODUCTION: While the U.S. has high quality data on firearm-related deaths, less information is available on those who arrive at trauma centers alive, especially those discharged from the emergency department. This study sought to describe characteristics of patients arriving to trauma centers alive following a firearm injury, postulating that significant differences in firearm injury intent might provide insights into injury prevention strategies. METHODS: This was a multi-center prospective cohort study of patients treated for firearm-related injuries at 128 U.S. trauma centers from 3/2021-2/2022. Data collected included patient-level sociodemographic, injury and clinical characteristics, community characteristics, and context of injury. The outcome of interest was the association between these factors and the intent of firearm injury. Measures of urbanicity, community distress, and strength of state firearm laws were utilized to characterize patient communities. RESULTS: 15,232 patients presented with firearm-related injuries across 128 centers in 41 states. Overall, 9.5% of patients died, and deaths were more common among law enforcement and self-inflicted (SI) firearm injuries (80.9% and 50.5%, respectively). These patients were also more likely to have a history of mental illness. SI firearm injuries were more common in older White men from rural and less distressed communities, whereas firearm assaults were more common in younger, Black men from urban and more distressed communities. Unintentional injuries were more common among younger patients and in states with lower firearm safety grades whereas law enforcement-related injuries occurred most often in unemployed patients with a history of mental illness. CONCLUSIONS: Injury, clinical, sociodemographic, and community characteristics among patients injured by a firearm significantly differed between intents. With the goal of reducing firearm-related deaths, strategies and interventions need to be tailored to include community improvement and services that address specific patient risk factors for firearm injury intent. LEVEL OF EVIDENCE: Level III, Prognostic/Epidemiological.
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BACKGROUND: Severe traumatic brain injury (TBI) is a leading cause of pediatric mortality, with a disproportionate burden on low- and middle-income countries. The impact of concomitant extracranial injury (ECI) on these patients remains unclear. This study is the first to characterize the epidemiology and clinical course of severe pediatric TBI with extracranial injuries in any South American country. METHODS: We conducted a secondary analysis of baseline data collected prior to implementation of a clinical trial on TBI care in Argentina, Paraguay, and Chile from September 2019 to July 2020. Patients ≤18 years with CT evidence of TBI, and a Glasgow coma scale (GCS) score ≤8 were recruited. Patients were initially stratified by highest non-head abbreviated injury scale (AIS): isolated TBI (AIS=0), minor extracranial injury (MEI; AIS=1-2), and serious extracranial injury (SEI; AIS≥3). Patients were subsequently stratified by mechanism of injury. Intergroup differences were compared using ANOVA, two-tailed unpaired t-tests, and chi-square tests. RESULTS: Among the 116 children included, 33 % (n = 38) had an isolated TBI, 34 % (n = 39) had MEI, and 34 % (n = 39) had SEI. Facial (n = 53), thoracic (n = 44), and abdominal (n = 31) injuries were the most common ECIs. At discharge, there were no significant differences in median GCS, GOS, or GOS-extended between groups. Patients with SEI had a longer hospital LOS than those with isolated TBI (median 28.0 (IQR 10.6-40.1) vs 11.9 (IQR 8.7-20.7) days, p = 0.013). The most common mechanisms of injury were road traffic injuries (RTIs) (n = 50, 43 %) and falls (n = 35, 30 %). Patients with RTI-associated TBIs were more likely to be older (median 11.0 (IQR 3.0-14.0) vs 2.0 (IQR 0.8-7.0) years, p<0.001) and more likely to have an ECI (86% vs 54 %, respectively; p = 0.003). ICU and Hospital LOS for RTI patients (median 10.5 (IQR 6.1-21.1) and 24.1 (IQR 11.5-40.4) days) were longer than those of fall patients (median 6.1 (IQR 2.6-8.9) and 13.7 (IQR 7.7-24.5) days). CONCLUSIONS: Extracranial injuries are common in South American patients with severe TBI. Severe ECI is more frequently associated with RTIs and can result in a higher rate of surgical procedures and LOS. Further strategies are needed to characterize the prevention and treatment of severe pediatric TBI in the South American context.
Subject(s)
Brain Injuries, Traumatic , Humans , Child , Brain Injuries, Traumatic/therapy , Patient Discharge , Glasgow Coma Scale , Hospitals , ChileABSTRACT
INTRODUCTION: Firearm-related injuries in the U.S. have risen 37% since 2015. Understanding how the association between firearm incidents and state-level firearm restrictiveness is modified by community-level distress and economic connectedness (EC) may inform upstream injury prevention efforts. METHODS: A national cross-sectional study of firearm incidents (interpersonal and unintentional firearm events) occurring between 1/2015 and 12/2021 was performed using the Gun Violence Archive. The exposures were community distress (Distressed Communities Index, DCI), EC, and year-state-level firearm restrictiveness. The primary outcome was mean annual urban firearm incidence rate per ZIP Code Tabulation Area. Generalized linear mixed models were fit to evaluate the modification of the firearm law-firearm incident association by DCI and EC. Data analyses took place in 2022. RESULTS: About 266,020 firearm incidents were included. The mean rate was higher with each DCI tertile, with a RR of 3.18 (95% CI: 3.06, 3.30) in high versus low distress communities. Low EC was associated with over 1.8 times greater rate of firearm-related injury. The least restrictive firearm laws were associated with 1.20 times higher risk of firearm incidents (95% CI: 1.12, 1.28). The association between restrictive laws and lower incidence rates was strongest in low and medium distress and high EC communities. CONCLUSIONS: Stricter firearm laws are associated with lower rate of firearm incidents. The magnitude of this association is smallest for communities experiencing the greatest economic disadvantage.
Subject(s)
Firearms , Gun Violence , Wounds, Gunshot , Humans , United States/epidemiology , Homicide , Wounds, Gunshot/epidemiology , Wounds, Gunshot/prevention & control , Cross-Sectional Studies , Gun Violence/prevention & controlABSTRACT
BACKGROUND: Early transfer to specialized centers improves trauma and burn outcomes; however, overtriage can result in unnecessary burdens to patients, providers, and health systems. Our institution developed novel burn triage pathways in 2016 to improve resource allocation. We evaluated the implementation of these pathways, analyzing trends in adoption, resource optimization, and pathway reliability after implementation. METHODS: Triage pathways consist of transfer nurses (RNs) triaging calls based on review of burn images and clinical history: green pathway for direct outpatient referral, blue pathway for discussion with the on-call provider, red pathway for confirmation of transfer as requested by referring provider, and black pathway for the rapid transfer of severe burns. We used the RE-AIM (Reach, Effectiveness, Adoption, Implementation, Maintenance) framework to evaluate implementation. These pathways affected all acute burn referrals to our center from January 2017 to December 2019 (reach). Outcomes of interest were pathway assignment over time (adoption), changes to burn provider call volume (effectiveness), and the concordance of pathway assignment with final disposition (implementation reliability). RESULTS: Transfer RNs triaged 5,272 burn referrals between 2017 and 2019. By January 2018, >98% of referrals were assigned a pathway. In 2018-2019, green pathway calls triaged by RNs reduced calls to burn providers by a mean of 40 (SD, 11) per month. Patients in green/blue pathways were less likely to be transferred, with >85% receiving only outpatient follow-up ( p < 0.001). Use of the lower acuity pathways increased over time, with a concordant decrease in use of the higher acuity pathways. Younger adults, patients referred from Level III to Level V trauma centers and nontrauma hospitals, and patients referred by APPs were less likely to be triaged to higher acuity pathways. CONCLUSION: Implementation of highly adopted, reliable triage pathways can optimize existing clinical resources by task-shifting triage of lower acuity burns to nursing teams. LEVEL OF EVIDENCE: Prognostic and Epidemiological; Level III.
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Burn Units , Triage , Adult , Humans , Reproducibility of Results , Referral and Consultation , Trauma Centers , Retrospective StudiesABSTRACT
BACKGROUND: Prior evaluations of ICU readmission among injured older adults have inconsistently identified risk factors, with findings limited by use of sub-analyses and small sample sizes. This study aimed to identify risk factors for and implications of ICU readmission in injured older adults. METHODS: This retrospective, single-center cohort study was conducted at a High-Volume Level 1 Trauma Center and included injured older adult patients (>65 years old) requiring at least one ICU admission during hospitalization between 2013-2018. Patients who died <48 hours of admission were excluded. Exposures included patient demographics and clinical factors. The primary outcome was ICU readmission. Multi-variable regression was used to identify risk factors for ICU readmission. RESULTS: 6,691 injured adult trauma patients were admitted from 2013-2018, 55.4% (n = 3,709) of whom were admitted to the ICU after excluding early deaths. Of this cohort, 9.1% (n = 339) were readmitted to the ICU during hospitalization. Readmitted ICU patients had a higher median Injury Severity Score (21 (IQR: 14-26) vs 16 (IQR: 10-24)), with similar mechanisms of injury between the two groups. Readmitted ICU patients had a significantly higher mortality (19.5%) compared to single ICU admission patients (9.9%) (p < 0.001) and higher rates of developing any complication, including delirium (61% vs 30%, p < 0.001). On multivariable analysis, the factors associated with the highest risk of readmission were delirium (RR = 2.6, 95% CI 2.07 - 3.26) and aspiration (RR = 3.04, 95% CI 1.67- 5.54). More patients in the single ICU admission cohort received comfort-focused care at the time of their death as compared to the ICU readmission cohort (93% vs 85%, p = 0.035). CONCLUSIONS: Readmission to the ICU is strongly associated with higher mortality for injured older adults. Efforts targeted at preventing respiratory complications and delirium in the geriatric trauma population may decrease the rates of ICU readmission and related mortality risk. LEVEL OF EVIDENCE: III/Epidemiologic.
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Firearm deaths continue to be a major public health problem, but the number of non-fatal firearm injuries and the characteristics of patients and injuries is not well known. The American College of Surgeons Committee on Trauma, with support from the National Collaborative on Gun Violence Research, leveraged an existing data system to capture lethal and non-lethal injuries, including patients treated and discharged from the emergency department and collect additional data on firearm injuries that present to trauma centers. In 2020, Missouri had the 4th highest firearm mortality rate in the country at 23.75/100,000 population compared to 13.58/100,000 for the US overall. We examined the characteristics of patients from Missouri with firearm injuries in this cross-sectional study. Of the overall 17,395 patients, 1,336 (7.7%) were treated at one of the 11 participating trauma centers in Missouri during the 12-month study period. Patients were mostly male and much more likely to be Black and uninsured than residents in the state as a whole. Nearly three-fourths of the injuries were due to assaults, and overall 7.7% died. Few patients received post-discharge services.
Subject(s)
Firearms , Wounds, Gunshot , Humans , Male , Female , Missouri/epidemiology , Wounds, Gunshot/epidemiology , Cross-Sectional Studies , Aftercare , Patient Discharge , ViolenceABSTRACT
BACKGROUND: While firearm injuries and deaths continue to be a major public health problem, the number of non-fatal firearm injuries and the characteristics of patients is not well known. The American College of Surgeons (ACS) Committee on Trauma leveraged an existing data system to collect additional data on fatal and non-fatal firearm injuries presenting to trauma centers. This report provides an overview of this initiative and highlights the challenges associated with capturing actionable data on firearm-injured patients. METHODS: 128 trauma centers that are part of the ACS Trauma Quality Improvement Program (TQIP) collected data on individuals of any age arriving alive between March 1, 2021 and February 28, 2022 with a firearm injury. In addition to the standard data collected for TQIP, abstractors also extracted additional data specific to this study. We linked data from the Distressed Community Index (DCI) to patient records using zip code of residence. RESULTS: A total of 17,395 patients were included, with mean (SD) age of 30.2 (13.5) years, 82.5% were male and the majority were Black and non-Hispanic. The mean proportion of variables with missing data varied among trauma centers, with a mean of 20.7% missing data. Injuries occurred most commonly in homes (31.2%) or on the street (26.6%); 70.4% of injuries were due to assaults. Nearly one-third of patients were discharged from the ED, 25.9% were admitted directly to the operating room, 10.9% to the ICU; 5.9% died in the ED and 10.3% died overall during their course of care. Nearly two-thirds of patients lived in the two highest distressed categories of communities; only 7.5% lived in the least distressed quintile. CONCLUSIONS: Utilizing trauma center data can be a valuable tool to improve our knowledge of firearm injuries if clinical practices and documentation of patient risks and circumstances are standardized. LEVEL OF EVIDENCE: III Level, epidemiological.
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BACKGROUND: Regionalized care for burn-injured patients requires accurate triage. In 2016, we implemented a tele-triage system for acute burn consultations. We evaluated resource utilization following implementation, hypothesizing that this system would reduce short-stay admissions and prioritize inpatient care for those with higher burn severity. STUDY DESIGN: We conducted a retrospective study of all transferred patients with acute burn injuries from January 1, 2010 to December 31, 2015, and January 1, 2017 to December 31, 2019. We evaluated the proportions of short-stay admissions (discharges less than 24 hours without operative intervention, ICU admission, or concern for nonaccidental trauma) among patients transferred before (2010 to 2015) and after (2017 to 2019) triage system implementation. Multivariable Poisson regression was used to evaluate factors associated with short-stay admissions. Interrupted time series analysis was used to evaluate the effect of the triage system. RESULTS: There were 4,688 burn transfers (3,244 preimplementation and 1,444 postimplementation) in the study periods. Mean age was higher postimplementation (32 vs 29 years, p < 0.001). Median hospital length of stay (LOS) and ICU LOS were both 1 day higher, more patients underwent operative intervention (19% vs 16%), and median time to first operation was 1 day lower postimplementation. Short-stay admissions decreased from 50% (n = 1,624) to 39% (n = 561), and patients were 17% less likely to have a short-stay admission after implementation (adjusted relative risk [aRR], 0.83; 95% CI, 0.8 to 0.9). Pediatric patients younger than 15 years old composed 43% of all short-stay admissions and were much more likely than adult patients to have a short-stay admission independent of transfer timing (aRR, 2.36; 95% CI, 1.84 to 3.03). CONCLUSIONS: Tele-triage burn transfer center protocols reduced short-stay admissions and prioritized inpatient care for patients with more severe injuries. Pediatric patients remain more likely to have short-stay admission after transfer.
Subject(s)
Burn Units , Triage , Adult , Humans , Child , Adolescent , Retrospective Studies , Hospitalization , Length of StayABSTRACT
Importance: Firearm-related injuries are the leading cause of death among children and adolescents in the US. For youths aged 10 to 19 years, 64% of firearm-related deaths are due to assault. Understanding the association between the rate of death due to assault-related firearm injury and both community-level vulnerability and state-level gun laws may inform prevention efforts and public health policy. Objective: To assess the rate of death due to assault-related firearm injury stratified by community-level social vulnerability and state-level gun laws in a national cohort of youths aged 10 to 19 years. Design, Setting, and Participants: This national cross-sectional study used the Gun Violence Archive to identify all assault-related firearm deaths among youths aged 10 to 19 years occurring in the US between January 1, 2020, and June 30, 2022. Exposure: Census tract-level social vulnerability (measured by the Centers for Disease Control and Prevention social vulnerability index [SVI]; categorized in quartiles as low [<25th percentile], moderate [25th-50th percentile], high [51st-75th percentile], or very high [>75th percentile]) and state-level gun laws (measured by the Giffords Law Center gun law scorecard rating; categorized as restrictive, moderate, or permissive). Main Outcomes and Measures: Youth death rate (per 100 000 person-years) due to assault-related firearm injury. Results: Among 5813 youths aged 10 to 19 years who died of an assault-related firearm injury over the 2.5-year study period, the mean (SD) age was 17.1 (1.9) years, and 4979 (85.7%) were male. The death rate per 100â¯000 person-years in the low SVI cohort was 1.2 compared with 2.5 in the moderate SVI cohort, 5.2 in the high SVI cohort, and 13.3 in the very high SVI cohort. The mortality rate ratio of the very high SVI cohort compared with the low SVI cohort was 11.43 (95% CI, 10.17-12.88). When further stratifying deaths by the Giffords Law Center state-level gun law scorecard rating, the stepwise increase in death rate (per 100 000 person-years) with increasing SVI persisted, regardless of whether the Census tract was in a state with restrictive gun laws (0.83 in the low SVI cohort vs 10.11 in the very high SVI cohort), moderate gun laws (0.81 in the low SVI cohort vs 13.18 in the very high SVI cohort), or permissive gun laws (1.68 in the low SVI cohort vs 16.03 in the very high SVI cohort). The death rate per 100 000 person-years was higher for each SVI category in states with permissive compared with restrictive gun laws (eg, moderate SVI: 3.37 vs 1.71; high SVI: 6.33 vs 3.78). Conclusions and Relevance: In this study, socially vulnerable communities in the US experienced a disproportionate number of assault-related firearm deaths among youths. Although stricter gun laws were associated with lower death rates in all communities, these gun laws did not equalize the consequences on a relative scale, and disadvantaged communities remained disproportionately impacted. While legislation is necessary, it may not be sufficient to solve the problem of assault-related firearm deaths among children and adolescents.
Subject(s)
Firearms , Wounds, Gunshot , United States/epidemiology , Humans , Adolescent , Child , Male , Female , Cross-Sectional Studies , Census Tract , Centers for Disease Control and Prevention, U.S.ABSTRACT
This cross-sectional study assesses nonself-inflicted firearm-related deaths occurring at inpatient or outpatient facilities, hospice care, nursing homes, home, or other settings from 1999 to 2021.
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Firearms , Hospice Care , Wounds, Gunshot , Humans , United States/epidemiology , Nursing HomesABSTRACT
Pheochromocytomas are rare adrenal tumors that are often diagnosed in workup for endocrine causes of refractory hypertension, as an incidental imaging finding, or in patients with classic symptoms of headache, palpitations, and/or diaphoresis. We describe a case of pheochromocytoma presenting in a 63-year-old woman with spontaneous and multifocal subarachnoid and intracerebral hemorrhage without underlying vasculopathy. The patient previously had no documented episodes of hypertension and took no regular medications. She experienced sudden-onset severe headache and presented with hypertensive crisis. Cranial imaging showed bifrontal and right temporal convexal subarachnoid and intracerebral hemorrhage of unknown etiology. Cranial arterial catheterization showed no vascular malformation underlying the site of hemorrhage. Given concern for potential malignant etiology, cross-sectional body imaging was performed that revealed a 7-cm right adrenal heterogeneous mass. Biochemical workup demonstrated markedly elevated plasma metanephrine and normetanephrine levels, diagnostic of pheochromocytoma. She underwent α- and ß-blockade, and evaluation with a multidisciplinary team including repeat intracranial imaging to ensure resolution of the intracranial bleeding before definitive surgical management. She then underwent successful laparoscopic adrenalectomy. This case demonstrates that the workup of cryptogenic intracranial hemorrhage and hypertensive crisis should include evaluation for catecholamine-secreting tumors.
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Polymer conjugation increases an enzyme's circulation time and stability for use as a therapeutic agent, but this attachment indubitably affects its properties. Covalent attachment of multiple polyethylene glycol chains with sizes of either 2, 5, 10, or 20 kDa increases the molecular weight and hydrodynamic radius of the model enzyme trypsin. The sizes of these polymer-enzyme conjugates are increased to be within the recommended limits for PDEPT applications. The T(d) increases from 49 to 60 °C to expand the enzyme's workable range of conditions. This functionalization with PEG polymers of varying lengths maintains trypsin's enzymatic activity. Conjugate activities are 79-120% that of native trypsin at room temperature and 221-432% that of trypsin at 37 °C.