Abstract 439: Using the Time Interval Between R-Wave Detection and Maximum Compression Pressure to Target and Validate Delivery of Synchronized Chest Compressions During Pseudo Electro-Mechanical Dissociation

Circulation ◽  
2019 ◽  
Vol 140 (Suppl_2) ◽  
Author(s):  
Joshua W Lampe ◽  
Jeff R Gould ◽  
Karen L Moodie ◽  
Zachary P Soucy ◽  
Peter S Burrage ◽  
...  
Keyword(s):  
Blood Flow ◽  
Time Interval ◽  
Hemodynamic Parameters ◽  
Chest Compressions ◽  
Compression Pressure ◽  
Carotid Blood Flow ◽  
Maximum Compression ◽  
Local Maxima ◽  
Blood Flows ◽  
Mechanical Dissociation

Introduction: The treatment of pseudo electro-mechanical dissociation (P-EMD) with standard chest compressions leads to some compressions that interfere with blood flow created by ventricular contraction and others that are synergistic. We have previously reported that the hemodynamics generated by standard chest compressions (StdCPR) depended on the time interval between the R-wave and the maximum compression pressure (t_int). Our goal was to use the t_int to identify the optimal timing for compression synchronization and to validate the delivery of synchronized chest compressions. Methods: Eight animals underwent surgical preparation and were exposed to hypoxia to induce P-EMD. The treatment period was divided into eight 45 sec epochs during which the P-EMD was left untreated or was treated with StdCPR or chest compressions synchronized to the R-wave in the ECG (SyncCPR). For each heart beat t_int was calculated as t peak AOP - t Rwave , blood pressures were averaged, and blood flows were integrated. 1,598 chest compressions were analyzed. The location of local extrema in hemodynamic parameters as a function of positive t_int values were identified recursively by dividing the range of t_int values into increasing numbers of bins and determining which bin had the highest mean value. Results: Blood flows and pressures exhibited a non-linear dependence on t_int. The maximum CPP occurred at t_int = 90 ±2.3 ms. The maximum aortic pressure occurred at t_int = 70 ±2.3 ms. The minimum right atrial pressure occurred at t_int = 280 ±2.3 ms. The maximum carotid blood flow occurred at t_int = 100 ±2.3 ms. The maximum jugular blood flow occurred at t_int = 400 ±2.3 ms. Unsynchronized chest compressions resulted in a t_int of -21 ± 170 ms. Synchronized chest compressions resulted in a t_int of 119 ± 13 ms. Conclusions: Local maxima and minima during StdCPR were identified in several hemodynamic parameters, but the extrema were not perfectly co-located. It appears that a t_int of 90-100 ms could be optimal. SyncCPR were delivered at 119 ms, which is not far from the local maxima observed for CPP and carotid blood flow.

Abstract 240: Comparison of Hemodynamics Generated by Synchronized and Interposed Compressions During Treatment of Pseudo Electro-mechanical Dissociation

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_4) ◽  
Author(s):  
Joshua W Lampe ◽  
Jill K Badin ◽  
Lyra Clark ◽  
Jeff R Gould ◽  
Karen L Moodie ◽  
...  
Keyword(s):  
Heart Rate ◽  
Blood Flow ◽  
Chest Compression ◽  
Right Atrial ◽  
Compression Rate ◽  
Chest Compressions ◽  
Blood Flows ◽  
Mechanical Dissociation ◽  
Life Threatening ◽  
Integrated Or

Introduction: Pseudo electro-mechanical dissociation (P-EMD) is a cardiac arrest variant characterized by a life-threatening reduction in cardiac output in the presence of organized electrical activity. Synchronization of chest compressions to the R-wave in the ECG may be preferable to the delivery of standard CPR. However, in the bradycardic P-EMD state, synchronization may result in inadequate blood flow due to the low compression/heart rate. This pilot study examined the hemodynamic effect of interposing additional chest compressions between synchronized chest compressions during bradycardic P-EMD to increase the compression rate. Methods: P-EMD was induced via hypoxia in three female swine (~30 kg) and treated with synchronized compressions until the onset of asystole (HR<12 BPM). Interposed compressions were added when the heart rate fell below 60 BPM. A chest compression was classified as synchronized or interposed depending on the presence or absence of a co-incident R-wave. Hemodynamic parameters were integrated or averaged over each compression interval. Results: Synchronized compressions tended to produce larger aortic pressures, larger carotid blood flows, and lower right atrial pressures than interposed compressions. Data from one experiment are shown in Figure 1. The relative hemodynamic benefit of a synchronized chest compression appears to depend on the effectiveness of the underlying heart contraction. The interposed chest compressions generated forward carotid blood flow and increased the compression rate during bradycardia. Discussion: During bradycardic P-EMD, synchronized compressions may generate better hemodynamics than interposed compressions, and the combination of synchronized and interposed compressions may result in more blood flow than the delivery of synchronized compressions alone. Figure 1. Comparison of hemodynamics generated by synchronized compressions (blue) and interposed compressions (red).

Effects of varying chest compression depths on carotid blood flow and blood pressure in asphyxiated piglets

2021 ◽  
pp. fetalneonatal-2020-319473
Author(s):  
Marlies Bruckner ◽  
Megan O’Reilly ◽  
Tze-Fun Lee ◽  
Mattias Neset ◽  
Po-Yin Cheung ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Blood Flow ◽  
Systolic Blood Pressure ◽  
Neonatal Resuscitation ◽  
Chest Compressions ◽  
Carotid Blood Flow ◽  
Newborn Piglets ◽  
Resuscitation Guidelines ◽  
Registration Number ◽  
Anterior Posterior

BackgroundCurrent neonatal resuscitation guidelines recommend chest compressions (CCs) should be delivered to a depth of approximately 1/3 of the anterior–posterior (AP) chest diameter. The aim of the study was to investigate the haemodynamic effects of different CC depths in a neonatal piglet model.MethodsCCs were performed with an automated CC machine with 33%, 40% and 25% AP chest diameter in all piglets in the same order for a duration of 3 min each.ResultsEight newborn piglets (age 1–3 days, weight 1.7–2.3 kg) were included in the study. Carotid blood flow (CBF) and systolic blood pressure were the highest using a CC depth of 40% AP chest diameter (19.3±7.5 mL/min/kg and 58±32 mm Hg).ConclusionCC depth influences haemodynamic parameters in asphyxiated newborn piglets during cardiopulmonary resuscitation. The highest CBF and systolic blood pressure were achieved using a CC depth of 40% AP chest diameter.Trial registration numberPCTE0000148.

Abstract 2230: Lower Extremity Counterpulsation During The Decompression Phase of CPR Improves Hemodynamics And Provides Continuous Forward Carotid Blood Flow.

Circulation ◽  
2007 ◽  
Vol 116 (suppl_16) ◽  
Author(s):  
Demetris Yannopoulos ◽  
Henry R Halperin ◽  
Johns Hopkins ◽  
Keith G Lurie
Keyword(s):  
Blood Flow ◽  
Lower Extremity ◽  
Cerebral Perfusion Pressure ◽  
Cerebral Perfusion ◽  
Perfusion Pressure ◽  
Fold Increase ◽  
Aortic Pressure ◽  
Hemodynamic Parameters ◽  
Carotid Blood Flow ◽  
Thoracic Decompression

Background: We hypothesize that lower extremity counterpulsations (LECP) during the decompression phase of CPR will increase diastolic aortic pressure without raising the intracranial pressure (ICP) and significantly increase forward carotid blood flow. Methods: In 6 (24±4Kg) pigs, 4 minutes of untreated VF were followed by 2 minutes epochs of standard (STD) CPR, STD +LECP, active compression decompression (ACD) +ITD and ACD + inspiratory impedance threshold device (ITD)+LECP. Compressions and ventilations were performed according to the 2005 AHA guidelines. A large blood pressure cuff that was circumferentially placed around the pig’s thighs avoiding the abdominal cavity was inflated with air to the point that manometer pressure started to rise. Compressions over the cuff were performed manually and synchronized with the thoracic decompression phase. The cuff was compressed up to 200mmHg. Basic hemodynamic parameters and common carotid blood flow (CCBF) (ml/min) were continuously measured. Cerebral perfusion pressure (CerPP) (mean arterial pressure - mean ICP) and CPP (diastolic AoP - diastolic RAP) were calculated at the end of the 2 minute epochs. Statistical analysis was performed with ANOVA. Results: LECP significantly increased diastolic aortic pressure, CPP and CerPP both when added on STD and on ACD+ITD CPR. The largest benefit was observed with ACD+ITD+LECP were there was a 2-fold increase in CPP and CerPP with a 2.5-fold increase in common carotid blood flow compared to STD CPR. LECP did not alter ICP. (Table 1 ). Decompression phase CCBF during ACD+ITD+LECP CPR was positive and reached pre cardiac arrest levels. Conclusion: LECP during thoracic decompression significantly augmented aortic diastolic pressure, CPP and CerPP without increasing the ICP . LECP led to a continuous positive cerebral perfusion pressure gradient during CPR cycles and in combination with ACD + ITD CPR common carotid blood flow reached pre-arrest levels. Hemodynamic Parameters

scholarly journals Continuous chest compressions with asynchronous ventilations increase carotid blood flow in the perinatal asphyxiated lamb model

2021 ◽  
Author(s):  
Payam Vali ◽  
Amy Lesneski ◽  
Morgan Hardie ◽  
Ziad Alhassen ◽  
Peggy Chen ◽  
...  
Keyword(s):  
Blood Flow ◽  
Chest Compressions ◽  
Carotid Blood Flow

Abstract 139: Impedance Threshold Device and Active Decompression Improve Hemodynamics in a Swine Model of Prolonged CPR

Circulation ◽  
2018 ◽  
Vol 138 (Suppl_2) ◽  
Author(s):  
Joshua W Lampe ◽  
Yin Tai ◽  
Anja K Metzger ◽  
Christopher L Kaufman ◽  
Lance B Becker
Keyword(s):  
Blood Flow ◽  
Chest Compression ◽  
Zero Point ◽  
Swine Model ◽  
Carotid Blood Flow ◽  
Blood Flows ◽  
Lift Height ◽  
Threshold Device ◽  
Acd Cpr ◽  
Impedance Threshold Device

Introduction: Cardiopulmonary resuscitation with the impedance threshold device and active decompression (ITD-ACD CPR) has been shown to improve chest compression generated blood flow relative to standard chest compression. Using our high-fidelity swine model of cardiac arrest treated with prolonged mechanical chest compression (MCC) we studied the effect of different lift heights (amount of lift above the natural zero point of the sternum) during active decompression. Methods: CPR was performed on six domestic swine (~30 kg) using standard physiological monitoring. Flow was measured in the abdominal aorta, inferior vena cava (IVC), right common carotid and external jugular, and left femoral artery. Ventricular fibrillation (VF) was electrically induced. MCC were started after ten minutes of VF. Four MCC waveforms were used: Standard CPR (2”, 100 CPM), and ITD-ACD CPR (2”, 80 CPM) with 0.5”, 1.0”, and 1.5” lift past the zero point. MCC waveforms were changed every 2 min in a crossover design and delivered for 56 minutes. Data were analyzed in CPR cycles which included four epochs of CPR, one of each waveform, constituting 8 minutes of compressions. Results: Lift height had a significant (p<0.05) effect on carotid and jugular blood flow. Lift heights of 1.0 and 1.5” generated significantly more carotid blood flow in all 7 CPR cycles. A lift height of 1.5” generated significantly more jugular blood flow over all 7 CPR cycles. The interaction between duration of CPR and Jugular blood flow previously observed using this animal model was not observed. Carotid and jugular blood flow as a function of waveform and CPR cycle are shown in the figure. Conclusions: ITD-ACD CPR improved carotid and jugular blood flows, suggestive of improved cerebral perfusion. A lift height of 1.5” was required for significant improvement of jugular blood flows, while ITD-ACD CPR provided significantly better carotid blood flow than standard CPR at all lift heights.

COMPARISON OF CAROTID BLOOD FLOW DURING CPR AND CHEST COMPRESSIONS WITH CPAP IN A PORCINE MODEL

1998 ◽  
Vol 86 (Supplement) ◽  
pp. 128S
Author(s):  
ZG Hevesi ◽  
&NA; Thrush ◽  
JB Downs ◽  
RA Smith
Keyword(s):  
Blood Flow ◽  
Porcine Model ◽  
Chest Compressions ◽  
Carotid Blood Flow

The Lack of Vasoconstrictor Effect of the Pineal Hormone Melatonin in an Animal Model Predictive of Antimigraine Activity

Cephalalgia ◽  
2001 ◽  
Vol 21 (6) ◽  
pp. 656-663 ◽  
Author(s):  
B Tom ◽  
P De Vries ◽  
JPC Heiligers ◽  
EW Willems ◽  
E Scalbert ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Animal Model ◽  
Blood Flow ◽  
Carotid Artery ◽  
Haemodynamic Effects ◽  
Vascular Conductance ◽  
Carotid Blood Flow ◽  
Blood Flows ◽  
Vasoconstrictor Effect

The pineal hormone, melatonin, has been implicated in the pathophysiology of migraine and several studies have demonstrated its vasoconstrictor properties. In the present study, systemic and carotid haemodynamic effects of melatonin, administered directly into the carotid artery, were investigated in anaesthetized pigs. Ten-minute intracarotid infusions of melatonin (1, 10 and 100 μg kg−1 min−1) produced slight decreases in blood pressure and total carotid and arteriovenous anastomotic blood flows, but nutrient blood flow was not affected. The decrease in carotid blood flow was entirely caused by the hypotension, since no changes in vascular conductance values were observed. It is concluded that melatonin itself is not capable of producing vasoconstriction in the cranial circulation of anaesthetized pigs. Thus, it appears that melatonin has no anti-migraine potential via a vasoconstrictor mechanism.

scholarly journals Corpuls CPR Generates Higher Mean Arterial Pressure Than LUCAS II in a Pig Model of Cardiac Arrest

2017 ◽  
Vol 2017 ◽  
pp. 1-9 ◽  
Author(s):  
S. Eichhorn ◽  
A. Mendoza ◽  
A. Prinzing ◽  
A. Stroh ◽  
L. Xinghai ◽  
...  
Keyword(s):  
Blood Flow ◽  
Chest Compression ◽  
Near Infrared ◽  
Coronary Perfusion Pressure ◽  
Spontaneous Circulation ◽  
Pig Model ◽  
Coronary Perfusion ◽  
Organ Perfusion ◽  
Chest Compressions ◽  
Carotid Blood Flow

According to the European Resuscitation Council guidelines, the use of mechanical chest compression devices is a reasonable alternative in situations where manual chest compression is impractical or compromises provider safety. The aim of this study is to compare the performance of a recently developed chest compression device (Corpuls CPR) with an established system (LUCAS II) in a pig model. Methods. Pigs (n = 5/group) in provoked ventricular fibrillation were left untreated for 5 minutes, after which 15 min of cardiopulmonary resuscitation was performed with chest compressions. After 15 min, defibrillation was performed every 2 min if necessary, and up to 3 doses of adrenaline were given. If there was no return of spontaneous circulation after 25 min, the experiment was terminated. Coronary perfusion pressure, carotid blood flow, end-expiratory CO2, regional oxygen saturation by near infrared spectroscopy, blood gas, and local organ perfusion with fluorescent labelled microspheres were measured at baseline and during resuscitation. Results. Animals treated with Corpuls CPR had significantly higher mean arterial pressures during resuscitation, along with a detectable trend of greater carotid blood flow and organ perfusion. Conclusion. Chest compressions with the Corpuls CPR device generated significantly higher mean arterial pressures than compressions performed with the LUCAS II device.

COMPARISON OF ANTIHYPERTENSIVE EFFECT OF MOXONIDINE VERSUS CLONIDINE IN RENAL FAILURE PATIENTS.

2018 ◽  
Vol 6 (9) ◽  
Author(s):  
DR.MATHEW GEORGE ◽  
DR.LINCY JOSEPH ◽  
MRS.DEEPTHI MATHEW ◽  
ALISHA MARIA SHAJI ◽  
BIJI JOSEPH ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Renal Failure ◽  
Blood Flow ◽  
Blood Vessel ◽  
Blood Vessels ◽  
High Blood Pressure ◽  
Antihypertensive Effect ◽  
The Body ◽  
Ability To Work ◽  
Blood Flows

Blood pressure is the force of blood pushing against blood vessel walls as the heart pumps out blood, and high blood pressure, also called hypertension, is an increase in the amount of force that blood places on blood vessels as it moves through the body. Factors that can increase this force include higher blood volume due to extra fluid in the blood and blood vessels that are narrow, stiff, or clogged(1). High blood pressure can damage blood vessels in the kidneys, reducing their ability to work properly. When the force of blood flow is high, blood vessels stretch so blood flows more easily. Eventually, this stretching scars and weakens blood vessels throughout the body, including those in the kidneys.

Myocardial blood flow determined with krypton 85 in unanesthetized dogs

1962 ◽  
Vol 203 (1) ◽  
pp. 122-124 ◽  
Author(s):  
J. A. Herd ◽  
M. Hollenberg ◽  
G. D. Thorburn ◽  
H. H. Kopald ◽  
A. C. Barger
Keyword(s):  
Blood Flow ◽  
Coronary Artery ◽  
Myocardial Blood Flow ◽  
Exponential Function ◽  
Scintillation Detector ◽  
Left Ventricular ◽  
Blood Flows ◽  
Single Exponential Function ◽  
Single Exponential ◽  
Rapid Measurements

Serial, rapid measurements of left ventricular myocardial blood flow in trained, unanesthetized dogs have been made by injecting krypton 85 through chronically implanted coronary artery catheters and counting with an external scintillation detector. Precordial radioactivity declined as a single exponential function during the first 2 min after injection, suggesting a single rate of myocardial blood flow. Simultaneous estimations with Kr85 and blood flowmeters in acute experiments established the accuracy and reproducibility of the technique. Myocardial blood flows between 40 and 55 ml/100 g/min were observed repeatedly in three well-trained, unanesthetized dogs in the basal state.

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