Vratislav Mrazek

Hyperinvasive approach to out-of hospital cardiac arrest using mechanical chest compression device, prehospital intraarrest cooling, extracorporeal life support and early invasive assessment compared to standard of care. A randomized parallel groups comparative study proposal. “Prague OHCA study”

BackgroundOut of hospital cardiac arrest (OHCA) has a poor outcome. Recent non-randomized studies of ECLS (extracorporeal life support) in OHCA suggested further prospective multicenter studies to define population that would benefit from ECLS. We aim to perform a prospective randomized study comparing prehospital intraarrest hypothermia combined with mechanical chest compression device, intrahospital ECLS and early invasive investigation and treatment in all patients with OHCA of presumed cardiac origin compared to a standard of care.MethodsThis paper describes methodology and design of the proposed trial. Patients with witnessed OHCA without ROSC (return of spontaneous circulation) after a minimum of 5 minutes of ACLS (advanced cardiac life support) by emergency medical service (EMS) team and after performance of all initial procedures (defibrillation, airway management, intravenous access establishment) will be randomized to standard vs. hyperinvasive arm. In hyperinvasive arm, mechanical compression device together with intranasal evaporative cooling will be instituted and patients will be transferred directly to cardiac center under ongoing CPR (cardiopulmonary resuscitation). After admission, ECLS inclusion/exclusion criteria will be evaluated and if achieved, veno-arterial ECLS will be started. Invasive investigation and standard post resuscitation care will follow. Patients in standard arm will be managed on scene. When ROSC achieved, they will be transferred to cardiac center and further treated as per recent guidelines.Primary outcome6 months survival with good neurological outcome (Cerebral Performance Category 1–2). Secondary outcomes will include 30 day neurological and cardiac recovery.DiscussionAuthors introduce and offer a protocol of a proposed randomized study comparing a combined “hyperinvasive approach” to a standard of care in refractory OHCA. The protocol is opened for sharing by other cardiac centers with available ECLS and cathlab teams trained to admit patients with refractory cardiac arrest under ongoing CPR. A prove of concept study will be started soon. The aim of the authors is to establish a net of centers for a multicenter trial initiation in future.Ethics and registrationThe protocol has been approved by an Institutional Review Board, will be supported by a research grant from Internal Grant Agency of the Ministry of Health, Czech Republic NT 13225-4/2012 and has been registered under ClinicalTrials.gov identifier: NCT01511666.

Primary angioplasty in acute myocardial infarction with right bundle branch block: should new onset right bundle branch block be added to future guidelines as an indication for reperfusion therapy?

Aims The current guidelines recommend reperfusion therapy in acute myocardial infarction (AMI) with ST-segment elevation or left bundle branch block (LBBB). Surprisingly, the right bundle branch block (RBBB) is not listed as an indication for reperfusion therapy. This study analysed patients with AMI presenting with RBBB [with or without left anterior hemiblock (LAH) or left posterior hemiblock (LPH)] and compared them with those presenting with LBBB or with other electrocardiographic (ECG) patterns. The aim was to describe angiographic patterns and primary angioplasty use in AMI patients with RBBB. Methods and results A cohort of 6742 patients with AMI admitted to eight participating hospitals was analysed. Baseline clinical characteristics, ECG patterns, coronary angiographic, and echocardiographic data were correlated with the reperfusion therapies used and with in-hospital outcomes. Right bundle branch block was present in 6.3% of AMI patients: 2.8% had RBBB alone, 3.2% had RBBB + LAH, and 0.3% had RBBB + LPH. TIMI flow 0 in the infarct-related artery was present in 51.7% of RBBB patients vs. 39.4% of LBBB patients (P = 0.023). Primary percutaneous coronary intervention (PCI) was performed in 80.1% of RBBB patients vs. 68.3% of LBBB patients (P< 0.001). In-hospital mortality of RBBB patients was similar to LBBB (14.3 vs. 13.1%, P = 0.661). Patients with new or presumably new blocks had the highest (LBBB 15.8% and RBBB 15.4%) incidence of cardiogenic shock from all ECG subgroups. Percutaneous coronary intervention was done more frequently (84.8%) in patients with new or presumably new RBBB when compared with other patients with blocks (old RBBB 66.0%, old LBBB 62.3%, new or presumably new LBBB 73.0%). In-hospital mortality was highest (18.8%) among patients presenting with new or presumably new RBBB, followed by new or presumably new LBBB (13.2%), old LBBB (10.1%), and old RBBB (6.4%). Among 35 patients with acute left main coronary artery occlusion, 26% presented with RBBB (mostly with LAH) on the admission ECG. Conclusion Acute myocardial infarction with RBBB is frequently caused by the complete occlusion of the infarct-related artery and is more frequently treated with primary PCI when compared with AMI + LBBB. In-hospital mortality of patients with AMI and RBBB is highest from all ECG presentations of AMI. Restoration of coronary flow by primary PCI may lead to resolution of the conduction delay on the discharge ECG. Right bundle branch block should strongly be considered for listing in future guidelines as a standard indication for reperfusion therapy, in the same way as LBBB.

Coronary versus carotid blood flow and coronary perfusion pressure in a pig model of prolonged cardiac arrest treated by different modes of venoarterial ECMO and intraaortic balloon counterpulsation

IntroductionExtracorporeal membrane oxygenation (ECMO) is increasingly used in cardiac arrest (CA). Adequacy of carotid and coronary blood flows (CaBF, CoBF) and coronary perfusion pressure (CoPP) in ECMO treated CA is not well established. This study compares femoro-femoral (FF) to femoro-subclavian (FS) ECMO and intraaortic balloon counterpulsation (IABP) contribution based on CaBF, CoBF, CoPP, myocardial and brain oxygenation in experimental CA managed by ECMO.MethodsIn 11 female pigs (50.3 ± 3.4 kg), CA was randomly treated by FF versus FS ECMO ± IABP. Animals under general anesthesia had undergone 15 minutes of ventricular fibrillation (VF) with ECMO flow of 5 to 10 mL/kg/min simulating low-flow CA followed by continued VF with ECMO flow of 100 mL/kg/min. CaBF and CoBF were measured by a Doppler flow wire, cerebral and peripheral oxygenation by near infrared spectroscopy. CoPP, myocardial oxygen metabolism and resuscitability were determined.ResultsCaBF reached values > 80% of baseline in all regimens. CoBF > 80% was reached only by the FF ECMO, 90.0% (66.1, 98.6). Addition of IABP to FF ECMO decreased CoBF to 60.7% (55.1, 86.2) of baseline, P = 0.004. FS ECMO produced 70.0% (49.1, 113.2) of baseline CoBF, significantly lower than FF, P = 0.039. Addition of IABP to FS did not change the CoBF; however, it provided significantly higher flow, 76.7% (71.9, 111.2) of baseline, compared to FF + IABP, P = 0.026. Both brain and peripheral regional oxygen saturations decreased after induction of CA to 23% (15.0, 32.3) and 34% (23.5, 34.0), respectively, and normalized after ECMO institution. For brain saturations, all regimens reached values exceeding 80% of baseline, none of the comparisons between respective treatment approaches differed significantly. After a decline to 15 mmHg (9.5, 20.8) during CA, CoPP gradually rose with time to 68 mmHg (43.3, 84.0), P = 0 .003, with best recovery on FF ECMO. Resuscitability of the animals was high, both 5 and 60 minutes return of spontaneous circulation occured in eight animals (73%).ConclusionsIn a pig model of CA, both FF and FS ECMO assure adequate brain perfusion and oxygenation. FF ECMO offers better CoBF than FS ECMO. Addition of IABP to FF ECMO worsens CoBF. FF ECMO, more than FS ECMO, increases CoPP over time.

Severe Allergic Dermatitis After Closure of Foramen Ovale With Amplatzer Occluder

Allergic reaction to nitinol is rarely reported, and its incidence, symptoms, and course have not been clearly defined. We report an occurrence of severe progressive generalized exanthema 3 days after the implantation of an Amplatzer occluder for a patent foramen ovale, with symptoms disappearing immediately after surgical removal of the device 3 months later. The risks and possible prevention of allergic reaction to nickel and especially to titanium are discussed.

Early vancomycin, amikacin and gentamicin concentrations in pulmonary artery and pulmonary tissue are not affected by VA ECMO (venoarterial extracorporeal membrane oxygenation) in a pig model of prolonged cardiac arrest

BACKGROUND ECMO (extracorporeal membrane oxygenation) is increasingly used in severe hemodynamic compromise and cardiac arrest (CA). Pulmonary infections are frequent in these patients. Venoarterial (VA) ECMO decreases pulmonary blood flow and antibiotic availability in lungs during VA ECMO treated CA is not known. We aimed to assess early vancomycin, amikacin and gentamicin concentrations in the pulmonary artery as well as tracheal aspirate and to determine penetration ratios of these antibiotics to lung tissue in a pig model of VA ECMO treated CA. METHODS Twelve female pigs, body weight 51.5 ± 3.5 kg, were subjected to prolonged CA managed by different modes of VA ECMO. Anesthetized animals underwent 15 min of ventricular fibrillation (VF) followed by continued VF with ECMO flow of 100 mL/kg/min. Immediately after institution of ECMO, a 30 min vancomycin infusion (10 mg/kg) was started and amikacin and gentamicin boluses (7.5 and 3 mg/kg, respectively) were administered. ECMO circuit, aortic, pulmonary arterial, and tracheal aspirate concentrations of antibiotics were measured at 30 and 60 min after administration; penetration ratios were calculated. RESULTS All 30 min antibiotic concentrations and 60 min concentration for gentamicin in the pulmonary artery were no different than the aorta. However, the 60 min pulmonary artery vancomycin and amikacin values were significantly higher than aortic, 19.8 (14.3-21.6) vs. 17.6 (14.2-19.0) mg/L, p = 0.009, and 15.6 mg/L (11.0-18.6) vs. 11.2 (10.4-17.2) mg/L, p = 0.036, respectively. One hour penetration ratios were 18.5% for vancomycin, 34.9% for gentamicin and 38.8% for amikacin. CONCLUSION In a pig model of VA ECMO treated prolonged CA, despite diminished pulmonary flow, VA ECMO does not decrease early vancomycin, gentamicin, and amikacin concentrations in pulmonary artery. Within 1 h post administration, antibiotics can be detected in tracheal aspirate in adequate concentrations.

Intravenous irradiation of blood by N2 laser: rabbit organism immunity increase using a staphylococcal model

The capacity of erythrocytes to photohemolysis was researched in physiological solution with increasing percents of blood plasma by spectrophotometer Specord UV-VIS. The screening effect of plasma was founded during illumination of erythrocyte suspensions by completed light of the mercury lamp DRT-375. Much less effect was observed during the illumination of the light with (lambda) equals 365 nm. The screening effect of plasma was due to presence of a protein and aminoacid groups in plasma.