tbuckley/cabot-search huggingface dataset:
Abstract 308: A Preoxygenation “Bundle” Decreases Desaturation Events and Improves Intubation Success in Air Medical Rapid Sequence Intubation
Authors: Justin Lemieux, Anushirvan Minokadeh, Jason Lanning, Justin Marayag, Daniel Davis
Journal: Circulation (2012)

Introduction: Oxygen desaturation occurs frequently in the course of prehospital rapid sequence intubation (RSI) and has been associated with increased morbidity and mortality. Preoxygenation with positive-pressure ventilation (PPV) may delay the onset of desaturation. However, PPV may not be used aggressively with emergency RSI due to concern for gastric insufflation precipitating regurgitation and aspiration events. Objective: To evaluate an aggressive preoxygenation protocol with regard to desaturation events during air medical RSI. Methods: The RSI protocol used in our air medical program airway training model was modified to employ several interventions designed to optimize preoxygenation prior to initial laryngoscopy. These included: two-person bag-valve-mask (BVM) ventilation, “two-thumbs-up” hand positioning on the mask, correct application of cricoid pressure, aggressive use of nasopharyngeal and oropharyngeal airways, small-volume assisted ventilation prior to administration of RSI medications, and large-volume ventilation following sedation/paralysis but prior to the initial laryngoscopy attempt. This algorithm identified a target SpO2 value of at least 93% based on a previous investigation. Desaturation events [decrease in SpO2 to &lt;90% or a continued decrease by at least 2% if initial SpO2 value was &lt;90%] were identified using physiologic data exported from hand held oximeter-capnometer devices. The incidence of desaturation events was established over a 2-year period prior to and the subsequent 2-year period following implementation of these algorithm changes. Results: A total of 155 RSI procedures were evaluated over the study period. Desaturation events decreased from 58% in the two years prior to the algorithm changes to 28% in the first year and 14% in the second year following implementation (chi-square test for trend p&lt;0.01). In addition, the intubation success rate increased from 94% to 97% following implementation of the protocol. There were no reports of major aspiration events during the study period. Conclusions: An aggressive preoxygenation protocol dramatically reduced the incidence of desaturation events and increased intubation success during air medical RSI without increasing aspiration events.
Abstract 9407: Overexpression of R120g αβ -Crystallin Causes Cardiac Arrhythmias, Reduced Heart Rate Variability, Alteration in the Expression Of Ca2+ Handling Proteins and Er Stress in Mice
Authors: Qibin Jiao, Atsushi Sanbe, Susumu Minamisawa
Journal: Circulation (2011)

Upregulation of αβ-crystallin (Cryαβ), a small heat shock protein, is associated with a variety of diseases, including desmin-related myopathies. Cryαβ, which binds to both desmin and cytoplasmic actin, may participate as a chaperone in intermediate filament formation and maintenance, and Cryαβ is abundant in cardiac and skeletal muscle. A mutation from arginine at the 120 amino acid residue to glycine (R120G) of Cryαβ has been linked to a familial desminopathy. Mice with cardiac specific overexpression of the R120G mutation in Cryαβ (CryαβR120G) have been known to suddenly die at 6-7 months without any obvious symptoms of heart failure. Therefoe, we investigated the cause of death in CryαβR120G transgenic mice. We prepared protein samples from the left ventricular tissues of the young and old mice (Young: 10 weeks, Old: 28 weeks), and examined a change in Ca2+ handling proteins. We found that the expression levels of SERCA2 and other Ca2+ handling proteins including phospholamban, ryanodine receptor 2, and calsequestrin 2 were significantly decreased in old CryαβR120G transgenic mice. Old CryαβR120G transgenic mice exhibited lower heart rate variability (HRV) such as heart rate, total power, and low frequency. In addition, continuous ECG monitoring uncovered that overexpression of CryαβR120G causesd cardiac arrhythmias such as ventricular tachycardia, atrioventricular block, and atrial flutter. We also found that the expression levels of endoplasmic reticulum (ER) degradation enhancing, α-mannosidase-like protein, inositol requirement 1, and x-box binding protein 1 mRNAs were significantly increased in old CryαβR120G transgenic mice, indicating that CryαβR120G transgenic mice exhibited ER stress. Thus the present study demonstrated that CryαβR120G lead to various arrhythmias, decreased autonomous tone, impaired Ca2+ regulation via the sarcoplasmic reticulum and enhanced ER stress with a concomitant decrease in lifespan.
Abstract 325: Differences in the Implications of the Time Interval from Collapse to Initiation of Cardiopulmonary Resuscitation and to Return of Spontaneous Circulation for the Prognosis of Out-of-Hospital Cardiac Arrest Patients
Authors: Eisuke Kagawa, Keigo Dote, Masaya Kato, Shota Sasaki, Yoshinori Nakano, Kiho Itakura, Yusuke Ochiumi, Yu Takiguchi, Hideko Honda, Ichiro Inoue, Takuji Kawagoe, Masaharu Ishihara, Yasuki Kihara
Journal: Circulation (2012)

Introduction : Out-of-hospital cardiac arrest patients have a poor prognosis even if cardiopulmonary resuscitation (CPR) is administered. The time interval from collapse to initiation of CPR (CA-CPR) and the time interval from collapse to return of spontaneous circulation (CA-ROSC) are reported to be predictors of survival in cardiac arrest patients. However, the clinical implications of both durations remain unclear. Hypothesis : We assessed the hypothesis that CA-CPR and CA-ROSC have different impacts on the prognosis of out-of-hospital cardiac arrest patients. Methods : We enrolled adult out-of-hospital cardiac arrest patients between 2006 and 2010 in this study. Receiver-operating characteristic curves of CA-CPR and CA-ROSC were generated to analyse favourable neurological outcomes. We assessed the independent predictors of return of spontaneous circulation (ROSC) and favourable neurological outcomes by using the logistic regression model. A P value of &lt; 0.05 was considered statistically significant. Results : We enrolled 1194 patients. The median age was 74 y (interquartile range 61-83 y); 61% were males. Fifty-two percent of the patients involved witnessed cardiac arrest; 76% of the patients were received by-stander CPR, 11% of the patients whose initial recorded rhythm was shockable rhythm. The CA-CPR for patients who achieved ROSC (n = 422) was shorter than that for patients who did not achieved ROSC (7 min (1-14 min) vs. 19 min (8-51 min), P &lt; 0.001). From the patients who achieved ROSC, the patients who had favourable neurological outcomes had shorter CA-CPR (2 min (1-7 min) vs. 8 min (2-15 min), P &lt; 0.001) and CA-ROSC (13 min (9-22 min) vs. 46 min (34-58 min), P &lt; 0.001). The area under the curve for the CA-CPR predicting ROSC was 0.74. The area under the curve for the CA-CPR and the CA-ROSC predicting favourable neurological outcomes in patients who achieved ROSC was 0.69 and 0.89, respectively. Multivariable analysis showed that the CA-CPR was associated with ROSC and CA-ROSC but not A-CPR was associated with favourable neurological outcomes. Conclusions : Early initiation of CPR is associated with ROSC, and early ROSC in turn is associated with favourable neurological outcomes in out-of-hospital cardiac arrest patients.
Abstract 9384: Differential Association of Epicardial Fat with Coronary Plaque in Patients with Acute Coronary Syndrome or Stable Angina Pectoris: Analysis by Integrated Backscatter Intravascular Ultrasound
Authors: Ken Harada, Tetsuya Amano, Tadayuki Uetani, Masataka Kato, Bunichi Kato, Tomohiro Yoshida, Hirohiko Ando, Ayako Kunimura, Yusaku Shimbo, Katsuhide Kitagawa, Kazuhiro Harada, Hideki Ishii, Tatsuaki Matsubara, Toyoaki Murohara
Journal: Circulation (2011)

Introduction: Epicardial fat is implicated in the pathogenesis of coronary atherosclerosis, but its precise contribution to this condition remains unclear. Objective: To evaluate the relations between epicardial adipose tissue and coronary plaque in patients with acute coronary syndrome (ACS) and those with stable angina pectoris (SAP). Methods: Atotal of 62 individuals (mean age, 67 ± 11 years; 64% men) who underwent percutaneous coronary intervention, including 20 patients with ACS and 42 patients with SAP, were enrolled in the study. Conventional and integrated backscatter intravascular ultrasound (IB-IVUS) was performed to assess coronary plaque in the patients. Plaque components were classified as calcified, dense-fibrous, fibrous, or lipid with the IB-IVUS system. The average plaque volume (total plaque volume/lesion length) and the percentage volumes of individual plaque components were calculated. Epicardial fat volume (EFV) was also measured by 64-slice computed tomography within 1 week of percutaneous coronary intervention. Results: There was no significant difference between ACS and SAP patient characteristics. EFV was significantly higher in patients with ACS than in those with SAP (117 ± 36 vs. 103 ± 40 ml, p &lt; 0.05). Multivariate regression analysis revealed that EFV was positively correlated with the percentage volume of dense-fibrous plaque ( r = 1.49, p &lt; 0.05) and negatively correlated with average plaque volume ( r = -0.58, p &lt; 0.05) in patients with ACS. However, no correlation between EFV and coronary plaque profile was apparent in patients with SAP. Conclusions: EFV was associated with the development of dense-fibrous plaque in ACS patients, whereas the average plaque volume decreased with increasing EFV in these patients. Our findings support the hypothesis that increased epicardial fat may contribute to the pathogenesis of ACS.
Abstract 264: Beneficial Effects of Therapeutic Hypothermia After Cardiac Arrest and CPR in Mice Require Nitric Oxide Synthase 3
Authors: Kotaro Kida, Joseph B Mandeville, Kenneth D Bloch, Fumito Ichinose
Journal: Circulation (2012)

Background : Therapeutic hypothermia (TH) improves neurological outcomes after ventricular fibrillation (VF)-induced cardiac arrest (CA), but the mechanisms by which TH elicits its beneficial effects are incompletely elucidated. Recently, we reported that inhaled nitric oxide (NO) improves outcomes after CA and CPR in mice. In this study, we tested the hypothesis that NO signaling is required for TH to improve outcomes after CA/CPR. We also sought to determine whether inhaled NO remains beneficial in mice treated with TH after CA and CPR. Methods : Adult male wild-type (WT) and NO synthase 3-deficient (NOS3 -/- ) mice were subjected to potassium-induced CA at 37°C for 8 and 6.5 minutes, respectively, at which time, CPR was performed with chest compression and mechanical ventilation. Body temperature was maintained at 37°C or reduced to 33°C starting 30 min after return of spontaneous circulation (ROSC) for 24h. TH-treated mice contemporaneously breathed air without or with NO (40 ppm). T2-weighted magnetic resonance imaging (MRI) was performed in live WT mice at 24h after CA/CPR. Results: Normothermic (NT) WT mice exhibited 100% mortality within 24h after CA/CPR. TH markedly improved the survival rate at 10 days in WT mice (43%; P&lt;0.05 vs NT). In WT mice treated with TH, breathing NO (NO+TH) further improved the survival rate after CA/CPR (88%, P&lt;0.05, NO+TH vs TH). NT NOS3 -/- mice exhibited 100% mortality within 24h after CA/CPR. TH failed to improve survival rate in NOS3 -/- mice, suggesting that NOS3 is required for the beneficial effects of TH after CA/CPR. NO breathing combined with TH improved the survival rate in NOS3 -/- mice after CA/CPR (67%, P&lt;0.01 vs NOS3 -/- TH). T2-weighted MRI in live mice showed hyperintense areas in the brainstem and ventral hippocampus of mice that were treated with TH alone consistent with development of vasogenic edema. NO+TH largely prevented the development of brain hyperintense regions (P&lt;0.05, NO+TH vs TH). Conclusions : The ability of TH to improve survival in mice subjected to CA/CPR requires NOS3 suggesting that NO signaling plays a critical role in the beneficial effects of TH. Inhaled NO can improve survival and reduce brain injury after CA/CPR even in mice treated with TH.
Abstract 9362: Argon Reduces Neurohistopathological Damage and Preserves Functional Recovery After Cardiac Arrest in Rats
Authors: Anne Bruecken, Carmen Fera, Axel Meinhardt, Joachim Weis, Rolf Rossaint, Michael Fries
Journal: Circulation (2011)

Introduction: Xenon has profound neuroprotective effects in various models of neurological injury and is currently undergoing phase two clinical trials in cardiac arrest patients. However, xenon is very costly which might preclude a widespread use. We hypothesized that the more available Argon might also protect central nervous tissues and functional recovery in a rodent model of global cerebral ischemia. Material and Methods: 14 male Sprague-Dawley rats were subjected to 7 mins of cardiac arrest and 3 mins of cardiopulmonary resuscitation (CPR). One hour after successful CPR, animals were randomized to ventilation with 70% Argon for 1h in comparison to untreated controls receiving 70% Nitrogen. A neurologic deficit score was calculated on seven days following the experiment before the animals were killed and the brains harvested for histopathological analyses. Results: All animals survived. Untreated controls exhibited severe neurological dysfunction while animals from the Argon group showed significant improvements at all points in time (Fig. 1). This was paralleled by a significant reduction in the degree of necrotic cell damage in the neocortex and the hippocampal CA 3/4 region (Fig. 2). Conlusions: Our study demonstrates that a single one hour application of 70% Argon provided a significant reduction in histopathological damage of the neocortex and hippocampus which was associated with a marked improvement in functional neurological recovery.
Abstract 338: Abdominal Fat Suspension Device for Maintaining Normal Cardiorespiratory Function in Obese Patients Undergoing Conscious Sedation During Surgery
Authors: Norman F Truong, Daeun Yoon, Gabriel Ochoa, Marisa Prevost, Sehyun Yun, Z Maria Oden, Mehdi Razavi
Journal: Circulation (2012)

Introduction: Obese patients undergoing surgical procedures that require conscious sedation have a heightened risk of perioperative morbidity because their excess abdominal tissue limits diaphragmatic excursion. We describe a simple, intuitive device that may help attenuate this increased risk. Methods: Our abdominal suspension device consists of 4 suction cups that grip onto the abdomen. The cups are attached to a horizontal beam that is supported by a height-adjustable frame anchored to both sides of the operating table. To confirm the efficacy of abdominal suspension for relieving stress on the heart, we tested 30 healthy subjects of normal weight in the supine position. We measured their heart rates with and without a 40-lb tissue model that was placed on the abdomen to simulate the excess abdominal weight seen in obese patients. Results: There was no significant difference in the average blood oxygen saturations before and after weight removal (97.7% vs. 97.5%, respectively; P =0.155). However, the decrease in heart rate was significant [76.2 vs. 68.9 beats/min, respectively, before and after weight removal; P &lt;0.01 ( P =4.36×10 -6 )], implying decreased respiratory effort as determined by a 1-tailed paired t test. Conclusion: By helping to maintain normal cardiorespiratory function in obese patients during surgical procedures requiring conscious sedation, our abdominal suspension device shows great promise for reducing unnecessary cardiac stress and preventing perioperative respiratory complications.
Abstract 9458: Coronary CT Angiography for Re-Adjustment of Pre-Test Probability of Obstructive Coronary Artery Disease
Authors: Shinichiro Fujimoto, Takeshi Kondo, Takahide Kodama, Tadaaki Orihara, Junichi Sugiyama, Makoto Kondo, Akira Endo, Hiroshi Fukazawa, Hideki Nagaoka, Akitsugu Oida, Shinichi Takase, Jagat Narula
Journal: Circulation (2011)

Backgrounds: Although various clinical algorithms have been proposed for defining pre-test probability of obstructive coronary artery disease (CAD), including Duke clinical score, these metrics suffer from selection bias of inclusion of predominantly high-risk population suitable for conventional coronary angiography. However, with noninvasive coronary CT angiography (CTA) comparative anatomy may also be available for a larger number of low and intermediate risk subjects, and may allow development of more inclusive algorithms. Methods: 3468 consecutive patients underwent CTA for suspected CAD (65.3±11.3 years, M:F: 1837:1811); patients with known CAD and those showing poor image quality were excluded from the study. Regression coefficients of age, gender, coronary risk factors including hypertension (HT), diabetes (DM), hyperlipidemia (HL) and smoking, history of cerebral infarction and chest symptoms (typical, atypical, or none) were weighed as predictors for CAD by multivariate analysis using logistic regression analysis against CTA findings. Risk score (K-risk) regarding the pre-test probability of CAD were calculated using each regression coefficients Results: Regression coefficients of age, gender, HT, DM, HL, smoking, history of cerebral infarction, chest symptom were 1.222, 0.039, 0.386, 0.768, 0.818, 0.385, 0.587, 0.431, respectively, and constant -6.404. The rate of concordance of K-risk and observation value was 82.8%. Area under curve of K-risk calculated by receiver operating characteristic curve was greater than that of Duke clinical score (0.769 vs 0.734 p=0.003). Conclusions: A K-risk score developed by comparison to CTA findings in the real-world population with suspected CAD allows for a superior assessment of pre-test probability of CAD. Further study for precision of it would be needed in a multicenter trial.
Abstract 341: Estrogen Prevents Sudden Death and Spontaneous Ventricular Fibrillation Associated with Pulmonary Hypertension via Estrogen Receptor Beta Mediated Mechanism
Authors: Soban Umar, Raymond Chui, Jonathan Hoffman, Aneesh Bapat, Hrayr S Karagueuzian, Mansoureh Eghbali
Journal: Circulation (2012)

Introduction: Previously we showed that right ventricular failure (RVF) secondary to pulmonary hypertension (PH) is associated with spontaneous ventricular fibrillation (VF) and sudden death in rats. We also discovered that estrogen (E2) therapy rescues severe PH and RVF. Estrogen receptor b (ERb) has been shown to play a protective role both in heart and lung. Here we hypothesize that E2 prevents sudden death and abolishes spontaneous VF associated with RVF through ERb. Methods: Male rats were treated with monocrotaline (MCT 60 mg/kg, s.c.) or PBS (CTRL, n=9). At day 21, MCT rats were left untreated to develop RVF by day 30 (n=9), or treated with E2 (42.5 ug/kg/day, s.c., n=9) with or without ERb antagonist PHTPP (850 ug/kg/day, s.c., n=8) from day 21 to day 30. RV ejection fraction (RVEF) was serially monitord with echocardiography. Direct RV catheterisation was performed terminally to record RV pressure (RVP). At ~day 30, hearts were studied in isolated-perfused Langendorff setting and microelectrode recordings were made. RV-epicardial activation pattern was optically mapped using fluorescent voltage-sensitive dye (RH-237). Trichrome staining was performed to assess cardiac fibrosis. Values are expressed as Mean±SEM. Results: By day 30, MCT rats developed severe PH (RVP=72±4 vs. 30±2 mmHg in CTRL, p&lt;0.05) and RV failure (RVEF=33±3% vs. 65±1 in CTRL, p&lt;0.05) with moderate RV fibrosis and ∼30% of RVF rats died suddenly. Early after depolarization (EADs) and spontaneous VF were observed in RVF group during normal Tyrode perfusion with wave front dynamics supported by both focal and multiple wavelet patterns. E2 therapy resulted in complete rescue of PH (RVP=38±3 mmHg, p&lt;0.05 vs. RVF; RVEF=60±2%, p&lt;0.05 vs. RVF; no signs of fibrosis) and none of the rats died in E2-groups. No VF was initiated in any of the control or E2 treated rat hearts. In the presence of ERb antagonist PHTPP, E2 could not rescue PH (RVP=60±4 vs. 38±3 in E2; RVEF=42±2 vs. 60±2 % in E2; p&lt;0.05 vs. E2); moderate RV fibrosis was present and spontaneous EADs and VF were observed in all the hearts similar to RVF group. Conclusions: In conclusion, E2-therapy rescues PH-induced RVF and prevents VF by reversing PH-induced RV-dysfunction and fibrosis most likely through ERb-mediated mechanism.
Abstract 282: Fat Intravasation from Intraosseous Infusions
Authors: Bernard J Rubal, Margaret A Hanson
Journal: Circulation (2012)

Rapid vascular access is an essential element in advanced resuscitation procedures and intraosseous (IO) cannulation has proven to be both a rapid and effective alternative to intravenous access. Little attention has been given to refinements in IO procedures that may improve efficacy or reduce complications of use. This study was designed to assess fat intravasation with IO infusions. In this study, IO cannulas (15G, EZ IO, Vidacare Corp, San Antonio, TX) were inserted into the proximal tibias (N=14) and distal femurs (N=11) of seven anesthetized swine ( Sus scrofa, 50.1±3.5 Kg). A lipophilic fluorescent probe (Nile red: Excitation 480nm-Emission 535nm) was used to quantify fat intravasation in venous effluents by relative fluorescent (RFU). Blood for analysis was withdrawn from an 8F catheter placed by fluoroscopic guidance in the external iliac vein. The IO infusion regimen consisted of an initial IO saline flush (10cc), infusion with a pressurized bag (300 mmHg), and infusions at 0.3, 0.5, 1.0, 2.0 and 3.0 ml per second using a programmable pump. An ANOVA and post hoc tests were employed to assess the significance of treatment effects. Figure illustrates significant (*P&lt;0.05) fat intravasation (mean ± SD) with initial flush and infusion rates ≥ 1ml per second. The post mortem assessment of lung tissue from these animals (N=79 samples) using formalin fixed H&amp;E stained sections and frozen sections stained with oil-red-O revealed mild to moderate positive staining for lipid in all lung segments and rare bone marrow emboli consisting of mature adipocytes and hematopoietic cells within medium sized pulmonary arteries. In conclusion, this study suggests that both initial flush and high flow rates induce medullary damage and the embolization of bone marrow and fat. Further studies are needed to determine if refinements in IO flush and infusion practices can maintain the benefits of IO infusions and minimize fat embolization.