Serum Lactate Level as a Predictor for Blood Transfusion in Postpartum Hemorrhage

OBJECTIVE

Postpartum hemorrhage (PPH) is the leading cause of maternal morbidity and mortality. At present, there are no reliable clinical or laboratory indicators to identify which patients might require blood transfusions during a PPH. Serum lactate has long been used as an early biomarker of tissue hypoperfusion in trauma settings. The aim of this study is to understand serum lactate's role in the management of obstetric hemorrhage.

STUDY DESIGN

A retrospective chart review was performed of women who delivered between 2016 and 2019 at our institution and experienced a PPH. The patients were divided into two groups: those with a normal serum lactate level, defined as ≤2 mmol/L, and those with an abnormal serum lactate level, defined as >2 mmol/L. Need for packed red blood cell transfusion, as part of the resuscitation, was assessed for both groups.

RESULTS

During the study period, 938 women experienced PPH. Of these, 108 (11.5%) had a normal serum lactate, ≤2 mmol/L, and 830 (88.5%) had an abnormal lactate, >2 mmol/L. Women with elevated lactate levels were more likely to receive a blood transfusion versus those with a normal lactate level (57.0 vs. 46.3%, p = 0.035, respectively). Additionally, the average number of blood transfusions administered was significantly higher in the abnormal lactate group versus in the normal lactate group (1.34 vs. 0.97, respectively, p = 0.004). In a multivariable linear regression model, increasing serum lactate levels were found to be predictive of requiring more than 1 unit of blood (p < 0.001).

CONCLUSION

Women with elevated serum lactate levels were more likely to require blood transfusions during a PPH versus those with a normal serum lactate level. Thus, serum lactate levels are useful as an early indicator of requirement for blood transfusion in the management of obstetric hemorrhage.

KEY POINTS

· Lactate is a biomarker for blood transfusion in trauma.. · Lactate's role in PPH is unknown.. · Elevated lactate predicts receiving more blood transfusions..

Long-term function, quality of life and healthcare utilization among survivors of pediatric out-of-hospital cardiac arrest

BACKGROUND

Survival following pediatric out-of-hospital cardiac arrest (OHCA) has improved over the past 2 decades but data on survivors' long-term outcomes are limited. We aimed to evaluate long-term outcomes in pediatric OHCA survivors more than one year after cardiac arrest.

METHODS

OHCA survivors <18 years old who received post-cardiac arrest care in the PICU at a single center between 2008-2018 were included. Parents of patients <18 years and patients ≥18 years at least one year after cardiac arrest completed a telephone interview. We assessed neurologic outcome (Pediatric Cerebral Performance Category [PCPC]), activities of daily living (Pediatric Glasgow Outcomes Scale-Extended, Functional Status Scale (FSS)), HRQL (Pediatric Quality of Life Core and Family Impact Modules), and healthcare utilization. Unfavorable neurologic outcome was defined as PCPC > 1 or worsening from pre-arrest baseline to discharge.

FINDINGS

Forty four patients were evaluable. Follow-up occurred at a median of 5.6 years [IQR 4.4, 8.9] post-arrest. Median age at arrest was 5.3 [1.3,12.6] years; median CPR duration was 5 [1.5, 7] minutes. Survivors with unfavorable outcome at discharge had worse FSS Sensory and Motor Function scores and higher rates of rehabilitation service utilization. Parents of survivors with unfavorable outcome reported greater disruption to family functioning. Healthcare utilization and educational support requirements were common among all survivors.

CONCLUSIONS

Survivors of pediatric OHCA with unfavorable outcome at discharge have more impaired function multiple years post-arrest. Survivors with favorable outcome may experience impairments and significant healthcare needs not fully captured by the PCPC at hospital discharge.

Deviations from PRx-derived optimal blood pressure are associated with mortality after cardiac arrest

AIM

Pressure reactivity index (PRx) provides a surrogate measurement of cerebrovascular autoregulation (CAR). We determined whether deviations from PRx-derived optimal mean arterial pressure (MAPopt) were associated with in-hospital mortality after adult cardiac arrest.

METHODS

Retrospective analysis of post-cardiac arrest patients who had continuously recorded intracranial pressure (ICP) and MAP. PRx was calculated as a moving, linear correlation between ICP and MAP. Impaired CAR was defined as PRx ≥ 0.3. MAPopt was calculated using a multi-window weighted algorithm. The burdens of MAP < 5 mmHg below MAPopt (MAPopt-5) and > 5 mmHg above MAPopt (MAPopt + 5) were calculated by integrating the area between MAP and MAPopt-5 or MAPopt + 5 curves, respectively. Univariate logistic regression tested the association between burden of MAP < MAPopt-5 and outcome.

RESULTS

Twenty-two patients were analyzed. Thirteen (59%) patients died before hospital discharge. Time (median [IQR]) between ROSC and monitoring initiation was 16 [14, 21] hours and duration of monitoring was 35 [22, 48] hours; neither differed between survivors and non-survivors. Median MAPopt was 89 [85, 97] mmHg and did not differ between survivors and non-survivors (89 [83, 94] vs. 91 [85, 105] mmHg, p = 0.64). Burden of MAP < MAPopt-5 was greater for non-survivors compared to survivors (OR 3.6 [95% CI 1.2-15.6]). Range of intact CAR (upper-lower limit) was narrower for non-survivors when compared to survivors (5 [0, 22] vs. 24 [7, 36] mmHg, p = 0.03).

CONCLUSION

A greater burden of MAP below PRx-derived MAPopt-5 was associated with mortality after cardiac arrest. Non-survivors had a narrower range of intact CAR than survivors.

Better Nurse Staffing Is Associated With Survival for Black Patients and Diminishes Racial Disparities in Survival After In-Hospital Cardiac Arrests

BACKGROUND

Racial disparities in survival among patients who had an in-hospital cardiac arrest (IHCA) have been linked to hospital-level factors.

OBJECTIVES

To determine whether nurse staffing is associated with survival disparities after IHCA.

RESEARCH DESIGN

Cross-sectional data from (1) the American Heart Association's Get With the Guidelines-Resuscitation database; (2) the University of Pennsylvania Multi-State Nursing Care and Patient Safety Survey; and (3) The American Hospital Association annual survey. Risk-adjusted logistic regression models, which took account of the hospital and patient characteristics, were used to determine the association of nurse staffing and survival to discharge for black and white patients.

SUBJECTS

A total of 14,132 adult patients aged 18 and older between 2004 and 2010 in 75 hospitals in 4 states.

RESULTS

In models that accounted for hospital and patient characteristics, the odds of survival to discharge was lower for black patients than white patients [odds ratio (OR)=0.70; 95% confidence interval (CI), 0.61-0.82]. A significant interaction was found between race and medical-surgical nurse staffing for survival to discharge, such that each additional patient per nurse lowered the odds of survival for black patients (OR=0.92; 95% CI, 0.87-0.97) more than white patients (OR=0.97; 95% CI, 0.93-1.00).

CONCLUSIONS

Our findings suggest that disparities in IHCA survival between black and white patients may be linked to the level of medical-surgical nurse staffing in the hospitals in which they receive care and that the benefit of being admitted to hospitals with better staffing may be especially pronounced for black patients.

The impact of increased chest compression fraction on survival for out-of-hospital cardiac arrest patients with a non-shockable initial rhythm

OBJECTIVE

We evaluated the effect of chest compression fraction (CCF) on survival to hospital discharge and return of spontaneous circulation (ROSC) in out-of-hospital cardiac arrest (OHCA) patients with non-shockable rhythms.

METHODS

This is a retrospective analysis (completed in 2016) of a prospective cohort study which included OHCA patients from ten U.S. and Canadian sites (Resuscitation Outcomes Consortium Epistry and PRIMED study (2007-2011)). We included all OHCA victims of presumed cardiac aetiology, not witnessed by emergency medical services (EMS), without automated external defibrillator shock prior to EMS arrival, receiving > 1 min of CPR with CPR process measures available, and initial non-shockable rhythm. We measured CCF using the first 5 min of electronic CPR records.

RESULTS

Demographics of 12,928 adult patients were: mean age 68; male 59.9%; public location 8.5%; bystander witnessed 35.2%; bystander CPR 39.3%; median interval from 911 to defibrillator turned on 10 min:04 s; initial rhythm asystole 64.8%, PEA 26.0%, other non-shockable 9.2%; compression rate 80-120/min (69.1%); median CCF 74%; ROSC 25.6%; survival to hospital discharge 2.4%. Adjusted odds ratio (OR); 95% confidence intervals (95%CI) of survival for each CCF category were: 0-40% (2.00; 1.16, 3.32); 41-60% (0.83; 0.54, 1.24); 61-80% (1.02; 0.77, 1.35); and 81-100% (reference group). Adjusted (OR; 95%CI) of ROSC for each CCF category were: 0-40% (1.02; 0.79, 1.30); 41-60% (0.83; 0.72, 0.95); 61-80% (0.85; 0.77, 0.94); and 81-100% (reference group).

CONCLUSIONS

We observed an incremental benefit from higher CCF on the incidence of ROSC, but not survival, among non-shockable OHCA patients with CCF higher than 40%.

Cryo scanning transmission x-ray microscope optimized for spectrotomography

A cryo scanning transmission X-ray microscope, the cryo-STXM, has been designed and commissioned at the Canadian Light Source synchrotron. The instrument is designed to operate from 100 to 4000 eV (λ = 12.4 - 0.31 nm). Users can insert a previously frozen sample, through a load lock, and rotate it ±70° in the beam to collect tomographic data sets. The sample can be maintained for extended periods at 92 K primarily to suppress radiation damage and a pressure on the order of 10^-9 Torr to suppress sample contamination. The achieved spatial resolution (30 nm) and spectral resolution (0.1 eV) are similar to other current soft X-ray STXMs, as demonstrated by measurements on known samples and test patterns. The data acquisition efficiency is significantly more favorable for both imaging and tomography. 2D images, 3D tomograms, and 4D chemical maps of automotive hydrogen fuel cell thin sections are presented to demonstrate current performance and new capabilities, namely, cryo-spectrotomography in the soft X-ray region.

Timing and modes of death after pediatric out-of-hospital cardiac arrest resuscitation

AIM

To determine the timing and modes of death of children admitted to a pediatric critical care unit (PICU) of a tertiary care center after an out-of-hospital cardiac arrest (OHCA).

METHODS

This is a retrospective descriptive study at a tertiary care PICU of all consecutive patients <18 years old who received ≥1 min of chest compressions, had return of spontaneous circulation (ROSC) for ≥20 min, and were admitted to the PICU after an OHCA. Modes of death were classified as brain death (BD), withdrawal due to neurologic prognosis (W/D-neuro), withdrawal for refractory circulatory failure (W/D-RCF), and re-arrest without ROSC (RA).

RESULTS

191 consecutive patients were admitted to the PICU from February 2005 to May 2013 after an OHCA. Eighty-six(45%) patients died prior to discharge: BD in 47%(40/86), W/D-neuro in 34%(29/86), W/D-RCF in 10%(9/86), and RA in 9%(8/86). Time to death was longer for patients with W/D-neuro: 4 days [1, 5] and BD 4 days [1, 5](p < 0.01) as opposed to those with W/D-RCF (1 day[1, 2]) and RA(1 day[0.5, 1]). Of patients who underwent W/D-neuro, 9/29(31%) died within 3 days of PICU admission and 20/29(69%) ≥3 days. Of patients who died after W/D-neuro, 12/29(41%) received therapeutic hypothermia, 27/29(93%) underwent EEG monitoring, 21/29(72%) had a brain CT, and 13/29(45%) had a brain MRI. All MRIs showed signs of hypoxic-ischemic injury.

CONCLUSION

Neurologic injury was the most common mode of death post-resuscitation care OHCA after in a tertiary care center PICU. Neurologic prognostication impacts the outcome of a large proportion of patients after OHCA, and further studies are warranted to improve its reliability.

Time on the scene and interventions are associated with improved survival in pediatric out-of-hospital cardiac arrest

BACKGROUND

Survival is less than 10% for pediatric patients following out-of-hospital cardiac arrest. It is not known if more time on the scene of the cardiac arrest and advanced life support interventions by emergency services personnel are associated with improved survival.

AIM

This study was performed to determine which times on the scene and which prehospital interventions were associated with improved survival.

METHODS

We studied patients aged 3 days to 19 years old with out-of-hospital cardiac arrest, using the Resuscitation Outcomes Consortium cardiac arrest database from 11 North American regions, from 2005 to 2012. We evaluated survival to hospital discharge according to on-scene times (<10, 10 to 35 and >35 min).

RESULTS

Data were available for 2244 patients (1017 infants, 594 children and 633 adolescents). Infants had the lowest rate of survival (3.7%) compared to children (9.8%) and adolescents (16.3%). Survival improved over the 7 year study period especially among adolescents. Survival was highest in the 10 to 35 min on-scene time group (10.2%) compared to the >35 min. group (6.9%) and the <10 min. group (5.3%, p=0.01). Intravenous or intra-osseous access attempts and fluid administration were associated with improved survival, whereas advanced airway attempts were not associated with survival and resuscitation drugs were associated with worse survival.

CONCLUSIONS

In this observational study, a scene time of 10 to 35 min was associated with the highest survival, especially among adolescents. Access for fluid resuscitation was associated with increased survival but advanced airway and resuscitation drugs were not.

Rhodium-catalyzed enantioselective silylation of arene C-H bonds: desymmetrization of diarylmethanols

We report a Rh-catalyzed, enantioselective silylation of arene C-H bonds directed by a (hydrido)silyl group. (Hydrido)silyl ethers that are formed in situ by hydrosilylation of benzophenone or its derivatives undergo asymmetric C-H silylation in high yield with excellent enantioselectivity in the presence of [Rh(cod)Cl]2 and a chiral bisphosphine ligand. The stereoselectivity of this process also allows enantioenriched diarylmethanols to react with site selectivity at one aryl group over the other. Enantioenriched benzoxasiloles from the silylation process undergo a range of transformations to form C-C, C-O, C-I, or C-Br bonds.

Cesarean scar pregnancies: experience of 60 cases

OBJECTIVES

To evaluate the management, clinical courses, and outcomes of cesarean scar pregnancies diagnosed in the first trimester.

METHODS

We identified 60 cases of cesarean scar pregnancies diagnosed between 5 and 14 weeks. Group A contained 48 patients with fetal/embryonic cardiac activity; group B comprised 12 patients without cardiac activity; and group C included 11 patients with cardiac activity who chose expectant management.

RESULTS

Five of the 48 patients (10.4%) in group A were successfully treated for vaginal bleeding. Thirty-three (68.7%) received methotrexate injections, and all had full resolution. Three (6.3%) required uterine artery embolization for late-developing arteriovenous malformations. Ten of the 12 patients (83.3%) in group B were managed expectantly and had full recovery. Two of the 10 (20.0%) had arteriovenous malformations; 1 had unsuccessful uterine artery embolization followed by a hysterectomy, and the second requested a hysterectomy. Ten of the 11 patients (90.9%) in group C continued the pregnancies. One declined local injection. Four of the 10 (40.0%) delivered live offspring by successive elective cesarean deliveries. Three (30.0%) had hysterectomies for placenta percreta, and 1 did not have a hysterectomy after delivery. Five (50%) had second-trimester complications, all leading to hysterectomies. Of the 60 patients, 20 (33.3%) had serious complications: 5 had arteriovenous malformations; 4 had uterine artery embolization; and 11 had hysterectomies.

CONCLUSIONS

A cesarean scar pregnancy is a serious complication for patients who have had cesarean deliveries. Counseling, treatment, and follow-up are challenging for patients and caregivers. However, emerging data from different management approaches confirm that a cesarean scar pregnancy may progress and result in a live neonate at the expense of further fertility. This study confirmed that expectant management of a cesarean scar pregnancy is associated with a high risk of hysterectomy due to morbidly adherent placenta.

PA Comments

I have just read and offer congratulations for the Winter 1980-81 edition of Practicing Anthropology which included 13 articles on anthropology in A.I.D. I read those articles with pride at the variety of experiences anthropologists report having in A.I.D. and, particularly, at the reports of respect for anthropology's contributions in A.I.D. professed by importantly placed non-social scientists. I know practically all the authors: the edition had the benefit from some of the best in A.I.D.

Age- and gender-dependent changes of bovine myocardium architecture

Growth, gravidity and lactation put high demands on the performance of the myocardium. The aim of this study, which was performed in 40 female and 20 male bovines ranging from 1 to 4.5 years old, was to determine gross and microscopic morphometric data of bovine myocardium to establish a comparative measure of myocardial growth during juvenile development. During the developmental stage of young adulthood, age-related increases in female myocardial characteristics included cardiac mass, left and right ventricular mass and the ratio of cardiac mass to loose connective tissue. Age-related decreases were observed in the number of myocyte nuclei per mm(2) and the thickness of the right ventricular wall. Sex differences in these parameters were found between 2-year-old bulls (N = 20) and 2-year-old heifers (N = 10), with males having heavier hearts, thicker ventricular walls, less myocytes in the left ventricle and less connective tissue in both ventricles. Age and sex had no influence on the ratio of capillaries to myocytes, estimated at 0.98 in the adult bovine. Capillary density does not change during juvenile development, but cross-sectional capillary area does adapt to myocyte cross-sectional area, accounting for this relatively constant ratio.

Evaluation of human peri-implant soft tissues around alumina-blasted/acid-etched standard and platform-switched abutments

This study evaluated the histometric characteristics of the peri-implant mucosa of human subjects that received textured implant abutments with conventional (implant and abutment with same diameter) or platform-switched (implant diameter wider than that of the abutment) configurations. Wider and longer connective tissue around platform-switched implants was observed compared to that with conventional abutments. Despite the different dimensions between the two abutment types, the abutment-soft tissue interaction was similar for both groups at the histometric level.

Relationship between chest compression rates and outcomes from cardiac arrest

BACKGROUND

Guidelines for cardiopulmonary resuscitation recommend a chest compression rate of at least 100 compressions per minute. Animal and human studies have reported that blood flow is greatest with chest compression rates near 120/min, but few have reported rates used during out-of-hospital (OOH) cardiopulmonary resuscitation or the relationship between rate and outcome. The purpose of this study was to describe chest compression rates used by emergency medical services providers to resuscitate patients with OOH cardiac arrest and to determine the relationship between chest compression rate and outcome.

METHODS AND RESULTS

Included were patients aged ≥ 20 years with OOH cardiac arrest treated by emergency medical services providers participating in the Resuscitation Outcomes Consortium. Data were abstracted from monitor-defibrillator recordings during cardiopulmonary resuscitation. Multiple logistic regression analysis assessed the association between chest compression rate and outcome. From December 2005 to May 2007, 3098 patients with OOH cardiac arrest were included in this study. Mean age was 67 ± 16 years, and 8.6% survived to hospital discharge. Mean compression rate was 112 ± 19/min. A curvilinear association between chest compression rate and return of spontaneous circulation was found in cubic spline models after multivariable adjustment (P=0.012). Return of spontaneous circulation rates peaked at a compression rate of ≈ 125/min and then declined. Chest compression rate was not significantly associated with survival to hospital discharge in multivariable categorical or cubic spline models.

CONCLUSIONS

Chest compression rate was associated with return of spontaneous circulation but not with survival to hospital discharge in OOH cardiac arrest.

High rate of non-eligibility: methodological factors impacting on recruitment for a multicentre, double-blind study of paediatric patients with major depressive disorder

INTRODUCTION

This report describes difficulties encountered when attempting to recruit children and adolescents with major depression for a recent international double-blind, placebo-controlled trial (www.clinicaltrials.gov Nr. NCT00849901).

METHODS

Over a 14-month period, children and adolescents with depressive symptoms were pre-screened for their eligibility for inclusion.

RESULTS

85 patients (age 7-17 years) were considered. Of these, only one was enrolled. The main reasons for non-eligibility were: failure to meet the baseline severity criterion on the primary outcome scale (clinical global impression-severity; 32.1% of the patients); requirement for immediate hospitalisation (15.4%); or the presence of an exclusionary comorbid psychiatric disorder (19.1%).

DISCUSSION

The recruitment of paediatric patients with major depression was primarily limited by various inclusion and exclusion criteria. Slow recruitment of small patient samples may impact strongly on the representativeness and generalisability of research findings, and thus on analyses in evidence-based medicine and on the development and recommendations of treatment guidelines. This may impact in turn on the feasibility of the clinical development and registration process of new compounds in paediatric psychopharmacology and beyond.

Epidemiology of out-of hospital pediatric cardiac arrest due to trauma

OBJECTIVE

To determine the epidemiology and survival of pediatric out-of-hospital cardiac arrest (OHCA) secondary to trauma.

METHODS

The CanAm Pediatric Cardiac Arrest Study Group is a collaboration of researchers in the United States and Canada sharing a common goal to improve survival outcomes for pediatric cardiac arrest. This was a prospective, multicenter, observational study. Twelve months of consecutive data were collected from emergency medical services (EMS), fire, and inpatient records from 2000 to 2003 for all OHCAs secondary to trauma in patients aged ≤18 years in 36 urban and suburban communities supporting advanced life support (ALS) programs. Eligible patients were apneic and pulseless and received chest compressions in the field. The primary outcome was survival to discharge. Secondary measures included return of spontaneous circulation (ROSC), survival to hospital admission, and 24-hour survival.

RESULTS

The study included 123 patients. The median patient age was 7.3 years (interquartile range [IQR] 6.0-17.0). The patient population was 78.1% male and 59.0% African American, 20.5% Hispanic, and 15.7% white. Most cardiac arrests occurred in residential (47.1%) or street/highway (37.2%) locations. Initial recorded rhythms were asystole (59.3%), pulseless electrical activity (29.1%), and ventricular fibrillation/tachycardia (3.5%). The majority of cardiac arrests were unwitnessed (49.5%), and less than 20% of patients received chest compressions by bystanders. The median (IQR) call-to-arrival interval was 4.9 (3.1-6.5) minutes and the on-scene interval was 12.3 (8.4-18.3) minutes. Blunt and penetrating traumas were the most common mechanisms (34.2% and 25.2%, respectively) and were associated with poor survival to discharge (2.4% and 6.5%, respectively). For all OHCA patients, 19.5% experienced ROSC in the field, 9.8% survived the first 24 hours, and 5.7% survived to discharge. Survivors had triple the rate of bystander cardiopulmonary resuscitation (CPR) than nonsurvivors (42.9% vs. 15.2%). Unlike patients sustaining blunt trauma or strangulation/hanging, most post-cardiac arrest patients who survived the first 24 hours after penetrating trauma or drowning were discharged alive. Drowning (17.1% of cardiac arrests) had the highest survival-to-discharge rate (19.1%).

CONCLUSIONS

The overall survival rate for OHCA in children after trauma was low, but some trauma mechanisms are associated with better survival rates than others. Most OHCA in children is preventable, and education and prevention strategies should focus on those overrepresented populations and high-risk mechanisms to improve mortality.

Outcomes after in-hospital cardiac arrest in children with cardiac disease: a report from Get With the Guidelines--Resuscitation

BACKGROUND

Small studies suggest that children experiencing a cardiac arrest after undergoing cardiac surgery have better outcomes than other groups of patients, but the survival outcomes and periarrest variables of cardiac and noncardiac pediatric patients have not been compared.

METHODS AND RESULTS

All cardiac arrests in patients <18 years of age were identified from Get With the Guidelines-Resuscitation from 2000 to 2008. Cardiac arrests occurring in the neonatal intensive care unit were excluded. Of 3323 index cardiac arrests, 19% occurred in surgical-cardiac, 17% in medical-cardiac, and 64% in noncardiac (trauma, surgical-noncardiac, and medical-noncardiac) patients. Survival to hospital discharge was significantly higher in the surgical-cardiac group (37%) compared with the medical-cardiac group (28%; adjusted odds ratio, 1.8; 95% confidence interval, 1.3-2.5) and the noncardiac group (23%; adjusted odds ratio, 1.8; 95% confidence interval, 1.4-2.4). Those in the cardiac groups were younger and less likely to have preexisting noncardiac organ dysfunction, but were more likely to have ventricular arrhythmias as their first pulseless rhythm, to be monitored and hospitalized in the intensive care unit at the time of cardiac arrest, and to have extracorporeal cardiopulmonary resuscitation compared with those in the noncardiac group. There was no survival advantage for patients in the medical-cardiac group compared with those in the noncardiac group when adjusted for periarrest variables.

CONCLUSION

Children with surgical-cardiac disease have significantly better survival to hospital discharge after an in-hospital cardiac arrest compared with children with medical-cardiac disease and noncardiac disease.

Microcirculatory and therapeutic effects of whole body periodic acceleration (pGz) applied after cardiac arrest in pigs

AIMS

Cardiac arrest (CA) and resuscitation are models of whole body ischemia reperfusion injury. Interventions performed prior to (pre-treatment) or after (post-treatment) can result in cardioprotection. Myocardial stunning, characterized by microcirculatory and contractile dysfunction after CA, is an important component of the post-cardiac arrest syndrome. Periodic acceleration (pGz), produced by the cyclical motion of the supine body headward to footward, increases microcirculatory blood flow to vital organs and elicits production of endothelial derived cytoprotective factors in normal animals. We tested the hypothesis that application of pGz 30 min after return of circulation from CA, as a delayed post-treatment strategy, would improve regional microcirculatory blood flow to vital organs and functional indices of myocardial stunning in pigs.

METHODS

8 min of unsupported VF followed by cardiopulmonary resuscitation and defibrillation was carried out in twenty anesthetized and paralyzed male swine who were randomized to delayed post-treatment with pGz (dPost) or none (CONT). pGz was begun 30 min after return of circulation along with conventional mechanical ventilation. Hemodynamics, echocardiogram, and regional blood flows were measured as well as biochemical index of cardiac tissue injury.

RESULTS

All animals had spontaneous return of circulation after cardiopulmonary resuscitation (CPR) and defibrillation. dPost animals had less myocardial stunning and greater regional blood flows to the heart, brain, kidneys, ileum and stomach than CONT. Post-treatment with pGz blunted the increase in Troponin I produced by CA and resuscitation, and, induced a greater rise in endothelial derived nitric oxide synthase (eNOS) and its phosphorylation (p-eNOS).

CONCLUSIONS

Delayed post-treatment with pGz as a therapeutic strategy, protects against early myocardial stunning in VF cardiac arrest by improving microcirculatory blood flow to the heart and also protects other vital organs by this mechanism.

Summary of NIH Medical-Surgical Emergency Research Roundtable held on April 30 to May 1, 2009

STUDY OBJECTIVE

In 2003, the Institute of Medicine Committee on the Future of Emergency Care in the United States Health System convened and identified a crisis in emergency care in the United States, including a need to enhance the research base for emergency care. As a result, the National Institutes of Health (NIH) formed an NIH Task Force on Research in Emergency Medicine to enhance NIH support for emergency care research. Members of the NIH Task Force and academic leaders in emergency care participated in 3 roundtable discussions to prioritize current opportunities for enhancing and conducting emergency care research. The objectives of these discussions were to identify key research questions essential to advancing the scientific underpinnings of emergency care and to discuss the barriers and best means to advance research by exploring the role of research networks and collaboration between the NIH and the emergency care community.

METHODS

The Medical-Surgical Research Roundtable was convened on April 30 to May 1, 2009. Before the roundtable, the emergency care domains to be discussed were selected and experts in each of the fields were invited to participate in the roundtable. Domain experts were asked to identify research priorities and challenges and separate them into mechanistic, translational, and clinical categories. After the conference, the lists were circulated among the participants and revised to reach a consensus.

RESULTS

Emergency care research is characterized by focus on the timing, sequence, and time sensitivity of disease processes and treatment effects. Rapidly identifying the phenotype and genotype of patients manifesting a specific disease process and the mechanistic reasons for heterogeneity in outcome are important challenges in emergency care research. Other research priorities include the need to elucidate the timing, sequence, and duration of causal molecular and cellular events involved in time-critical illnesses and injuries, and the development of treatments capable of halting or reversing them; the need for novel animal models; and the need to understand why there are regional differences in outcome for the same disease processes. Important barriers to emergency care research include a limited number of trained investigators and experienced mentors, limited research infrastructure and support, and regulatory hurdles. The science of emergency care may be advanced by facilitating the following: (1) training emergency care investigators with research training programs; (2) developing emergency care clinical research networks; (3) integrating emergency care research into Clinical and Translational Science Awards; (4) developing emergency care-specific initiatives within the existing structure of NIH institutes and centers; (5) involving emergency specialists in grant review and research advisory processes; (6) supporting learn-phase or small, clinical trials; and (7) performing research to address ethical and regulatory issues.

CONCLUSION

Enhancing the research base supporting the care of medical and surgical emergencies will require progress in specific mechanistic, translational, and clinical domains; effective collaboration of academic investigators across traditional clinical and scientific boundaries; federal support of research in high-priority areas; and overcoming limitations in available infrastructure, research training, and access to patient populations.