The Hemodynamic Effects of Aortic Regurgitation in Patients Supported by a HeartMate 3 Left Ventricular Assist Device.

BACKGROUND: Aortic regurgitation (AR) is a common complication following left ventricular assist device (LVAD) implantation. We evaluated the hemodynamic implications of AR in patients with HeartMate 3 (HM3) LVAD at baseline and in response to speed changes. METHODS AND RESULTS: Clinically stable outpatients supported by HM3 who underwent a routine hemodynamic ramp test were retrospectively enrolled in this analysis. Patients were stratified based on the presence of at least mild AR at baseline speed. Hemodynamic and echocardiographic parameters were compared between the AR and non-AR groups. Sixty-two patients were identified. At the baseline LVAD speed, 29 patients (47%) had AR, while 33 patients (53%) did not. Patients with AR were older and supported on HM3 for a longer duration. At baseline speed, all hemodynamic parameters were similar between the groups including central venous pressure, pulmonary capillary wedge pressure, pulmonary arterial pressures, cardiac output and index, and pulmonary artery pulsatility index (p > 0.05 for all). During the subacute assessment, AR worsened in some, but not all, patients, with increases in LVAD speed. There were no significant differences in 1-year mortality or hospitalization rates between the groups, however, at 1-year, ≥ moderate AR and right ventricular failure (RVF) were detected in higher rates among the AR group compared to the non-AR group (45% vs. 0%; p < 0.01, and 75% vs. 36.8%; p = 0.02, respectively). CONCLUSIONS: In a cohort of stable outpatients supported with HM3 who underwent a routine hemodynamic ramp test, the presence of mild or greater AR did not impact the ability of HM3 LVADs to effectively unload the left ventricle during early subacute assessment. Although the presence of AR did not affect mortality and hospitalization rates, it resulted in higher rates of late hemodynamic-related events in the form of progressive AR and RVF.

Disparities in Insurance Status Are Associated With Outcomes but Not Timing of Trauma Care.

INTRODUCTION: Patient factors influence outcomes after injury. Delays in care have a crucial impact. We investigated the associations between patient characteristics and timing of transfer from the emergency department to definitive care. METHODS: This was a review of adult trauma patients treated between January 1, 2016, and December 31, 2018. Bivariate analyses were used to build Cox proportional hazards models. We built separate logistic and negative binomial regression models for secondary outcomes using mixed-step selection to minimize the Akaike information criterion c. RESULTS: A total of 1219 patients were included; 68.5% were male, 56.8% White, 11.2% Black, and 7.8% Asian/Pacific Islander. The average age was 51 ± 21 y. Overall, 13.7% of patients were uninsured. The average length of stay was 5 d and mortality was 5.9%. Shorter transfer time out of the emergency department was associated with higher tier of activation (relative risk [RR] 1.39, 95% confidence interval [CI] 1.09-1.77; P = 0.0074), Injury Severity Score between 16 and 24 points (RR 1.57, 95% CI 1.04-2.32; P = 0.0307) or ≥25 (RR 3.85, 95% CI 2.45-5.94; P = 0.0001), and penetrating injury. Longer time to event was associated with Glasgow coma scale score ≥14 points (RR 0.47, 95% CI 0.27-0.85; P = 0.0141). Uninsured patients were less likely to be admitted (odds ratio 0.29, 95% CI 0.17-0.48; P = 0.0001) and more likely to experience shorter length of stay (incidence rate ratio 0.34, 95% CI 0.24-0.51; P = 0.0001). CONCLUSIONS: Injury characteristics and insurance status were associated with patient outcomes in this retrospective, single-center study. We found no disparity in timing of intrafacility transfer, perhaps indicating that initial management protocols preserve equity.

Skin Failure Among Critically Ill Patients Afflicted with Coronavirus Disease 2019 (COVID-19).

Objective: To characterize skin integrity among coronavirus disease 2019 (COVID-19) patients treated in the intensive care unit (ICU), and identify risk factors for skin failure (SF) in these patients. Design: The characteristic, profound pro-inflammatory, hypercoagulable state of COVID-19 is manifested by the high severity of illness and extensive organ dysfunction observed in these patients. SF in critically ill patients, although described previously, exhibits a uniquely complex pathogenesis in this population. Patients: Retrospective review of all COVID-19 patients (confirmed positive for severe acute respiratory syndrome coronavirus-2 [SARS-CoV-2]) admitted to a single surgical ICU for at least 48 hours between March-June 2020. Interventions: Data were extracted from a COVID-19 institutional data repository that harvested data from electronic health records and other clinical data sources. Demographics; coagulation/inflammation biomarkers; number, location, and stage of SF lesions; resource utilization; and outcomes were captured. Measurements and Main Results: 64 patients met inclusion criteria; 51 (80%) developed SF (SF+ ). Forty-three (85%) developed stage 3 or higher SF (χ2 = 22.66, P < .0001). Thirty-nine of 51 (76%) SF+ patients developed more than one SF lesion (χ2 = 13.26, P = .0003). SF+ patients manifested a profound pro-inflammatory, hypercoagulable phenotype (lower serum albumin and higher ferritin, interleukin [IL]-6 and D-dimer concentrations [all, P < .001]). Durations of mechanical ventilation, vasopressor therapy, and ICU length of stay were significantly longer (all, P < .05) in the SF + patients. Conclusions: The unique characteristics of COVID-19 dermatopathology and the strong correlation between markers of inflammation and development of SF reflect COVID-19-related organ dysfunction and its deleterious effects on the microcirculation. Considering that skin is invaded directly by SARS-CoV-2 and affected by COVID-19-related immune complex deposition and microthrombosis, SF may reflect disease as opposed to pressure injuries related to processes of care. In the context of COVID-19 critical illness, SF should not be considered a "never event."

Trauma Response Nurse: Bringing Critical Care Experience and Continuity to Early Trauma Care.

Multitrauma patients can benefit significantly from specialized care. Prior to mid-2016, this hospital's trauma team did not include a surgical intensive care unit (SICU) nurse. As the value of bringing this expertise to the patient upon arrival was realized, the role of the trauma response nurse (TRN) was developed. The TRN role was designed to provide a dedicated SICU nurse to care for trauma patients from emergency department (ED) arrival through disposition. The integration of the TRN role into the trauma team sought to improve quality and safety, as well as communication and collaboration, and enhance continuity of care. The primary responsibilities of the TRN were to assist with clinical interventions, transport patients fromthe ED to tests and procedures, and assume care through disposition. Additional TRN duties included education, community outreach, and performance improvement. TRNs now respond to all trauma activations that occur on weekday day shift. This role has improved collaboration between nursing disciplines, improved the overall function of the trauma team, and enhanced the safety of trauma patients during transport. TRNs make valuable contributions to the education and outreach missions of the trauma program and ensure that patients are receiving the highest level of trauma care.

Validation of the HeartMate 3 survival risk score in a large left ventricular assist device center.

OBJECTIVE: The HeartMate 3 survival risk score was recently validated in the Multicenter study Of MagLev Technology in Patients Undergoing Mechanical Circulatory Support Therapy with HeartMate 3 to predict patient-specific survival in HeartMate 3 left ventricular assist device candidates. The HeartMate 3 survival risk score stratifies individuals into tertiles according to survival probability. METHODS: We performed a single-center retrospective review of all HeartMate 3 left ventricular assist device recipients between September 2017 and August 2022. Baseline characteristics were collected from the electronic medical records. HeartMate 3 survival risk scores were calculated for all eligible patients. One- and 2-year Kaplan-Meier survival analyses were conducted. A univariate and multivariable Cox regression model was used to identify predictors. RESULTS: A total of 181 patients were included in this final analysis. The median age was 62 years, 83% were male, and 26% were Interagency Registry for Mechanically Assisted Circulatory Support Profile 1. The mean HeartMate 3 survival risk score for the entire cohort was 2.66 ± 0.66. Two-year survivals in the high, average, and low survival groups were 93.5% ± 3.2%, 81.6% ± 7.4%, and 82.0% ± 6.6%, respectively. As a continuous variable, the unadjusted HeartMate 3 survival risk score was a significant predictor of mortality (hazard ratio, 2.20; 95% CI, 1.08-4.45; P = .029). The areas under the curve were 0.70 and 0.66 at 1 and 2 years, respectively. We were unable to demonstrate the discriminatory ability of the HeartMate 3 survival risk score using the original stratification, but we found significantly increased survival in the high survival group using a binary cutoff (hazard ratio, 4.8; 95% CI, 1.01-20.9; P = .038). CONCLUSIONS: The unadjusted HeartMate 3 survival risk score was associated with postimplant survival in patients outside of the Multicenter study Of MagLev Technology in Patients Undergoing Mechanical Circulatory Support Therapy with HeartMate 3 but did not remain an independent predictor after adjusting for ischemic etiology and severe diabetes. The HeartMate 3 survival risk score was able to identify patients at high survival using a binary cutoff, but we were unable to demonstrate its discriminatory ability among the previously published risk tertiles.

Factors associated with limitation of care after fatal injury.

BACKGROUND: There is variability in end-of-life care of trauma patients. Many survive resuscitation but die after limitation of care (LoC). This study investigated LoC at a level I center. METHODS: Adult trauma deaths between January 2016 and June 2020 were reviewed. Patients were stratified into "full code" versus any LoC (i.e., do not resuscitate, no escalation, or withdrawal of care) and by timing to LoC. Emergency department and "brain" deaths were excluded. Unadjusted logistic regression and Cox proportional hazards were used for analyses. Results include n (%) and odds ratios (ORs) with 95% confidence intervals (CIs), with α = 0.05. RESULTS: A total of 173 patients were included; 15 patients (8%) died full code and 158 (91%) died after LoC. Seventy-seven patients (48%) underwent incremental LoC. Age (OR, 1.05; 95% CI, 1.02-1.08; p = 0.0010) and female sex (OR, 3.71; 95% CI, 1.01-13.64; p = 0.0487) increased the odds of LoC; number of anatomic injuries (OR, 0.91; 95% CI, 0.85-0.98; p = 0.0146), chest injuries (Abbreviated Injury Scale [AIS] score chest, >3) (OR, 0.02; 95% CI, 0.01-0.26; p = 0.0021), extremity injury (AIS score, >3) (OR, 0.08; 95% CI, 0.01-0.64; p = 0.0170), and hospital complications equal to 1 (OR, 0.21; 95% CI, 0.06-0.78; p = 0.0201) or ≥2 (OR, 0.19; 95% CI, 0.04-0.87; p = 0.0319) decreased the odds of LoC. For those having LoC, final limitations were implemented in <14 days for 83% of patients; markers of injury severity (e.g., Injury Severity Score, Glasgow Coma Scale score, and AIS score) increased the odds of early LoC implementation. CONCLUSION: Most patients died after LoC was implemented in a timely fashion. Significant head injury increased the odds of LoC. The number of injuries, severe chest and extremity injuries, and increasing number of complications decreased the odds of LoC, presumably because patients died before LoCs were initiated. Understanding factors contributing to end-of-life care could help guide discussions regarding LoCs. LEVEL OF EVIDENCE: Prognostic and Epidemiologic; Level III.

Thrombotic Events and Anticoagulation-Related Bleeding Complications in Critically Ill Patients with Coronavirus Disease 2019.

Background: Thrombosis (T) is common in coronavirus disease 2019 (COVID-19) patients, and d-dimer concentrations correlate with outcomes. Controversy exists with regards to anticoagulation (AC) for patients. We implemented a full-heparinization AC protocol from the onset of the pandemic and hypothesized that a safety signal would be undetectable. Patients and Methods: Prospective evaluation of 111 patients with COVID-19 critical illness hospitalized from March to June 2020. All patients received therapeutic heparinoid-based AC from admission. Incidences of T, bleeding (B), or both (BT) were noted. The primary outcome was mortality. Kruskal-Wallis test and logistic regression were performed. Results are expressed as n (%), median (interquartile range) and odds ratios with 95% confidence intervals. Alpha was set at 0.05. Results: Thirty-two patients (28%) had T, 23 (20%) had B, and 14 (12%) had BT; 42 (40%) patients were unaffected. Two logistic regression models (outcome = mortality) evaluated BT as T, or BT as B. For BT as T, neither T, B, nor male gender predicted mortality; similarly, for BT as B, neither T, B, nor male gender predicted mortality. Factors associated with higher odds of death included higher Acute Physiology and Chronic Health Evaluation (APACHE) II score (odds ratio [OR], 1.06; 95% confidence interval [CI], 1.00-1.13; p = 0.0045), higher d-dimer concentration (OR, 1.00; 95% CI, 1.00-1.01; p = 0.043), and higher activated partial thromboplastin time (aPTT; OR, 1.09; 95% CI, 1.02-1.16; p = 0.010). Conclusions: Neither T nor B predicted mortality in this prospective cohort of anticoagulated patients with COVID-19 critical illness. These data support continued full-dose heparinoid prophylaxis.

The recombinational anatomy of a mouse chromosome.

Among mammals, genetic recombination occurs at highly delimited sites known as recombination hotspots. They are typically 1-2 kb long and vary as much as a 1,000-fold or more in recombination activity. Although much is known about the molecular details of the recombination process itself, the factors determining the location and relative activity of hotspots are poorly understood. To further our understanding, we have collected and mapped the locations of 5,472 crossover events along mouse Chromosome 1 arising in 6,028 meioses of male and female reciprocal F1 hybrids of C57BL/6J and CAST/EiJ mice. Crossovers were mapped to a minimum resolution of 225 kb, and those in the telomere-proximal 24.7 Mb were further mapped to resolve individual hotspots. Recombination rates were evolutionarily conserved on a regional scale, but not at the local level. There was a clear negative-exponential relationship between the relative activity and abundance of hotspot activity classes, such that a small number of the most active hotspots account for the majority of recombination. Females had 1.2x higher overall recombination than males did, although the sex ratio showed considerable regional variation. Locally, entirely sex-specific hotspots were rare. The initiation of recombination at the most active hotspot was regulated independently on the two parental chromatids, and analysis of reciprocal crosses indicated that parental imprinting has subtle effects on recombination rates. It appears that the regulation of mammalian recombination is a complex, dynamic process involving multiple factors reflecting species, sex, individual variation within species, and the properties of individual hotspots.

Predictors of Mortality Among Pediatric Burn Patients in East Africa.

Little is known about the outcomes of pediatric burn patients in resource-limited and rural locations of the developing world. In March 2013, our pediatric burn unit existing in this setting established an electronic registry of all patients. The authors analyzed the registry to determine overall mortality rates and predictors of mortality, including that of underweight status and body part burned. The secure electronic database of all admissions was reviewed for age, gender, weight, burn percentage (TBSA%), body part burned, cause/place of injury, length of stay, underweight status, surgery performed, reason for discharge, and mortality. Univariable and multivariable logistic regression was used to determine the variables associated with mortality. Kaplan-Meier curves were also analyzed. A total of 211 cases (59.7% male) admitted from March 2013 to June 2014 were reviewed. The median age, %TBSA, and length of stay were 2.0 years (1.3-3.3), 8.0% (5.0-13.4), and 8.5 days (4-14). The overall mortality rate was 15/211 (7.1%). Most injuries were unintentional (93.8%) scalds (85.3%) occurring in the home (98.1%). Two factors were significantly associated with mortality in the final multivariable model: %TBSA (odds ratio = 1.31 for 1% increase in %TBSA; 95% confidence interval = 1.17-1.46) and younger age (odds ratio = 0.20; 0.07-0.63). This study characterizes mortality among patients at a pediatric burn unit serving a rural population in the developing world. The majority of pediatric burns were unintentional scalds occurring in the home. %TBSA and lower age were the strongest predictors of mortality. Burn location and underweight status were not independent predictors of mortality. Overall mortality was 7.1%. These data are applicable to improving outcomes for patients in this burn unit and similar settings of its kind.

A Pilot Study to Validate the Burn Center Pediatric Early Warning Score Tool in Clinical Practice.

The pediatric early warning score (PEWS) tool helps providers to detect subtle clinical deterioration in non-intensive care unit pediatric patients and intervene early to prevent significant adverse outcomes. Although widely used in general pediatrics, limited studies report on its validation; none report on use with burn-injured patients. New York-Presbyterian/Weill Cornell Medical Center modified a general PEWS system to a burn-specific PEWS and integrated its use into standard practice. This study investigated the external validity of the PEWS process in clinical practice. Fifty cases of patients aged 0 to 15.9 years admitted between January 2012 and June 2013, whose length of stay (LOS) more than 3 days were selected for review from this cohort of n equal to 187. Demographics, total PEWS and score changes, and compliance with PEWS documentation and with resultant interventions were reviewed. Continuous variables are presented as mean ± SD, P less than 0.05. Mean age, burn size, and LOS were 3.2 ± 3.3 years, 4.8 ± 5.7%, and 9.8 ± 7.0 days; 26% required grafting, and 50% were male. No mortalities occurred. One thousand six hundred and twelve PEWS from 1745 opportunities were documented (92.4%). For all PEWS (n = 1612) and PEWS greater than 0 (n = 912), means were 0.9 ± 1.2 and 1.6 ± 1.2, respectively. Among the 162 PEWS increase events, intake (54.1%) and output (4.5%) parameters increased most commonly. Of these, 129 PEWS increases (79.6%) were followed by an intervention that most commonly included text notation of score increase (93.7%), physician/physician assistant notification (70.5%), and feeding-tube insertion (25.6%). Patients with PEWS greater than 0 had similar age, LOS, and larger burn size (5.2% vs 1.4%, P < 0.05) than those with PEWS equal to 0. Compliance with PEWS performance and resultant actions based on score increases are high. Data support that even small changes in burn-injury specific PEWS stimulate provider discussion and intervention and support its validation; further studies on its effect on practice are warranted.

The treatment of posttraumatic stress disorder and related psychosocial consequences of burn injury: a pilot study.

Burn injuries are unique in their medical and psychological impact, yet there has been little exploration of psychiatric treatment for this population. This uncontrolled pilot study assessed feasibility, acceptability, and preliminary efficacy of a treatment protocol designed to address posttraumatic stress disorder, depression, coping with scarring, and community integration among adult burn survivors. A 14-session, manualized treatment protocol was created using cognitive-behavioral interventions including imaginal exposure, behavioral activation, cognitive restructuring, modeling, and in vivo exposure. Responses were measured using the Clinician Administered PTSD Scale, Beck Depression Index, Community Integration Questionnaire, Oswestry Disability Questionnaire, and Burn Specific Health Scale. Nine of 10 enrolled patients (60% women; mean = 42 years old) completed treatment. Burn size was 0.5% to 65%; mechanism of injury included flame (4), scald (5), and contact (1) burns. Mean acute hospitalization was 30.1 days (range = 13-87); mean time from injury to treatment was 3.2 months (range = 1-7). Baseline mean posttraumatic stress score was 68 on the Clinician Administered PTSD Scale (severe); scores decreased by 36% to a mean of 45.3 at posttreatment, with a large effect size. Baseline self-reported depression was 21 (moderate) on the Beck Depression Index, decreasing by 47% to a mean of 12 posttreatment (nonclinical). Change in community reintegration score was significant and large, and body image showed significant improvement. The protocol showed promise in the treatment of posttraumatic stress disorder, depression, self-image, and community reintegration following burn injury. These findings suggest that coping may improve with treatment and symptoms should not be dismissed as unavoidable consequences of burn injury.

Pediatric sink-bathing: a risk for scald burns.

Our burn center previously reported a significant incidence of scald burns from tap water among patients treated at the center. However, mechanism of these scalds was not investigated in detail. A recent series of pediatric patients who sustained scalds while bathing in the sink was noted. To evaluate the extent of these injuries and create an effective prevention program for this population, a retrospective study of bathing-related sink burns among pediatric patients was performed. Patients between the ages of 0 and 5.0 years who sustained scald burns while being bathed in the sink were included in this study. Sex, race, age, burn size, length of stay, and surgical procedures were reviewed. During the study period of January 2003 through August 2008, 56 patients who were scalded in the sink were admitted, accounting for 54% of all bathing-related scalds. Among these, 56% were boys and 45% were Hispanic. Mean age was 0.8 ± 0.1 years. Burn size and hospital length of stay averaged 5 ± 0.7% and 11 ± 1 days, respectively. Of this group, 10.7% required skin grafting. The overwhelming majority (94% of patients) were discharged home. The remaining patients were discharged to inpatient rehabilitation, foster care, and others. Pediatric scald burns sustained while bathing in a sink continue to be prevalent at our burn center. Because of limited space and the child's proximity to faucet handles and water flow, sinks are an unsafe location to bathe a child. While such practice may be necessary for some families, comprehensive burn prevention education must address this hazard.

New management strategy for fluid resuscitation: quantifying volume in the first 48 hours after burn injury.

This study evaluated a 24-hour resuscitation protocol, established a formula to quantify resuscitation volume for the second 24 hours, described the relationship between the first and second 24 hours, and identified which patients required high volumes. A protocol for patients with burn >15% TBSA was implemented in 2009. Initial fluid was based on the Parkland calculation and adjusted to meet a goal urine output. Protocol compliance was defined as appropriate fluid titration to maintain urine output. Resuscitation ratio in the second 24 hours was tabulated as total fluid /(evaporative loss + maintenance fluid + estimated colloid). Data were collected prospectively from 2009 to 2011. A Wilcoxon rank test compared differences between groups. Regression analyses analyzed volume administered. P < .05 was statistically significant. Forty patients with burn >15% TBSA met criteria for inclusion. Mean age, burn size, and resuscitation volumes in the first and second 24 hours (mean + SD) were 47+ 20.7 years, 29.9 + 14.6% TBSA, 7.4 + 3.7 ml/kg/% TBSA, and a ratio of 1.9 times expected volume (SD, 1.3), respectively. Protocol compliance was 34%. Intubation, older age, and increased narcotic administration correlated with higher resuscitation volumes. A higher resuscitation volume in the first 24 hours significantly correlated with a higher resuscitation volume in the second 24 hours (P < .001). In conclusion, there is a significant relationship between fluid administration in the first and second 24 hours of resuscitation; intubation, older age, and narcotics correlate with higher volumes. A formula for observed/expected volumes in the second 24 hours is total fluid/(evaporative loss + maintenance fluid +estimated colloid).

Engaging older adults in burn prevention education: results of a community-based urban initiative.

The objective of the study is to educate New York City seniors aged 60 years and older about fire safety and burn prevention through the use of a community-based, culturally sensitive delivery platform. The ultimate goal is to reduce burn injury morbidity and mortality among this at-risk population. Programming was developed and provided to older adults attending community-based senior centers. Topics included etiology of injury, factors contributing to burn injuries, methods of prevention, emergency preparedness, and home safety. Attendees completed a postpresentation survey. Of the 234 senior centers invited to participate in the program, 64 (27%) centers requested presentations, and all received the educational programming, reaching 2196 seniors. An additional 2590 seniors received education during community-based health fairs. A majority reported learning new information, found the presentation helpful, and intended to apply this knowledge to daily routines. Data confirm that many opportunities exist to deliver culturally sensitive burn prevention programming to the older adult population of this large metropolitan area in settings that are part of their daily lives. A majority of respondents welcomed the information, perceived it as helpful, and reported that they were likely to integrate the information into their lives.

Burn disaster response planning in New York City: updated recommendations for best practices.

Since its inception in 2006, the New York City (NYC) Task Force for Patients with Burns has continued to develop a city-wide and regional response plan that addressed the triage, treatment, transportation of 50/million (400) adult and pediatric victims for 3 to 5 days after a large-scale burn disaster within NYC until such time that a burn center bed and transportation could be secured. The following presents updated recommendations on these planning efforts. Previously published literature, project deliverables, and meeting documents for the period of 2009-2010 were reviewed. A numerical simulation was designed to evaluate the triage algorithm developed for this plan. A new, secondary triage scoring algorithm, based on co-morbidities and predicted outcomes, was created to prioritize multiple patients within a given acuity and predicted survivability cohort. Recommendations for a centralized patient and resource tracking database, plan operations, activation thresholds, mass triage, communications, data flow, staffing, resource utilization, provider indemnification, and stakeholder roles and responsibilities were specified. Educational modules for prehospital providers and nonburn center nurses and physicians who would provide interim care to burn injured disaster victims were created and pilot tested. These updated best practice recommendations provide a strong foundation for further planning efforts, and as of February 2011, serve as the frame work for the NYC Burn Surge Response Plan that has been incorporated into the New York State Burn Plan.

Patterns of recombination activity on mouse chromosome 11 revealed by high resolution mapping.

The success of high resolution genetic mapping of disease predisposition and quantitative trait loci in humans and experimental animals depends on the positions of key crossover events around the gene of interest. In mammals, the majority of recombination occurs at highly delimited 1-2 kb long sites known as recombination hotspots, whose locations and activities are distributed unevenly along the chromosomes and are tightly regulated in a sex specific manner. The factors determining the location of hotspots started to emerge with the finding of PRDM9 as a major hotspot regulator in mammals, however, additional factors modulating hotspot activity and sex specificity are yet to be defined. To address this limitation, we have collected and mapped the locations of 4829 crossover events occurring on mouse chromosome 11 in 5858 meioses of male and female reciprocal F1 hybrids of C57BL/6J and CAST/EiJ mice. This chromosome was chosen for its medium size and high gene density and provided a comparison with our previous analysis of recombination on the longest mouse chromosome 1. Crossovers were mapped to an average resolution of 127 kb, and thirteen hotspots were mapped to <8 kb. Most crossovers occurred in a small number of the most active hotspots. Females had higher recombination rate than males as a consequence of differences in crossover interference and regional variation of sex specific rates along the chromosome. Comparison with chromosome 1 showed that recombination events tend to be positioned in similar fashion along the centromere-telomere axis but independently of the local gene density. It appears that mammalian recombination is regulated on at least three levels, chromosome-wide, regional, and at individual hotspots, and these regulation levels are influenced by sex and genetic background but not by gene content.

Burn disaster response planning: an urban region's approach.

The objective of this study was to describe a draft response plan for the tiered triage, treatment, or transportation of 400 adult and pediatric victims (50/million population) of a burn disaster for the first 3 to 5 days after injury using regional resources. Review of meeting minutes and the 11 deliverables of the draft response plan was performed. The draft burn disaster response plan developed for NYC recommended: 1) City hospitals or regional burn centers within a 60-mile distance be designated as tiered Burn Disaster Receiving Hospitals (BDRH); 2) these hospitals be divided into a four-tier system, based on clinical resources; and 3) burn care supplies be provided to Tier 3 nonburn centers. Existing burn center referral guidelines were modified into a hierarchical BDRH matrix, which would vector certain patients to local or regional burn centers for initial care until capacity is reached; the remainder would be cared for in nonburn center facilities for up to 3 to 5 days until a city, regional, or national burn bed becomes available. Interfacility triage would be coordinated by a central team. Although recommendations for patient transportation, educational initiatives for prehospital and hospital providers, city-wide, interfacility or interagency communication strategies and coordination at the State or Federal levels were outlined, future initiatives will expound on these issues. An incident resulting in critically injured burn victims exceeding the capacity of local and regional burn center beds may be a reality within any community and warrants a planned response. To address this possibility within New York City, an initial draft of a burn disaster response has been created. A scaleable plan using local, state, regional, or federal health care and governmental institutions was developed.

The impact of a legislative intervention to reduce tap water scald burns in an urban community.

To review the efficacy municipal legislation in the reduction of tap water scald burns among an urban population. A retrospective chart and database review of patients hospitalized at this burn center between July 1999 and June 2004 for treatment of tap water scalds were performed. Demographic information and injury details, including extent of injury and age, type and location of the dwelling in which the injury occurred, were reviewed. Citywide incidence of these injuries for periods before and after a local prevention law was enacted was also calculated. Hospital costs for acute care treatment of these injuries were estimated. Tap water scalds increased from 15 to 22 per million/yr after legislation enactment. This burn center treated 281 of these patients during 5 years of the study period. Patients experienced significant morbidity and mortality. All cases (100%) occurred in structures exempt from current legislation. Citywide treatment costs were estimated between $102 and $148,000,000. In New York City, tap water scald burns remain a significant public health risk and continue to occur within buildings exempt from current law. Future injuries may potentially be prevented by expanding the law to include all residential buildings, regardless of building age or minimum occupancy.