Engineering Commons^™

Cardiac, Thoracic, And Abdominal Pump Mechanisms In Cardiopulmonary Resuscitation: Studies In An Electrical Model Of The Circulation, Charles F. Babbs, Christopher Weaver, Sandra H. Ralston, Leslie A. Geddes

Weldon School of Biomedical Engineering Faculty Publications

To investigate alternative mechanisms generating artificial circulation during cardiopulmonary resuscitation (CPR), an electrical model of the circulation was developed. Heart and blood vessels were modeled as resistive-capacitive networks; pressures in the chest, abdomen, and vascular compartments as voltages; blood flow as electric current; blood inertia as inductance; and the cardiac and venous valves as diodes. External pressurization of thoracic and abdominal vessels, as would occur in CPR, was simulated by application of half-sinusoidal voltage pulses. Three modes of creating artificial circulation were studied: cardiac pump (CP), in which the atria and ventricles of the model were pressurized simultaneously; thoracic pump …

Intrapulmonary Epinephrine During Prolonged Cardipulmonary Resuscitation: Improved Regional Blood Flow And Resuscitation In Dogs, Sandra H. Ralston, William D. Voorhees, Charles F. Babbs

Weldon School of Biomedical Engineering Faculty Publications

Blood flow to vital organs was measured at five-minute intervals during 20 minutes of cardiopulmonary resuscitation (CPR) and ventricular fibrillation in two groups of anesthetized dogs (n = 15 per group). The relationship between organ blood flow and restoration of circulation after 20 minutes was assessed with no additional treatment in Group I and with intrapulmonary epinephrine in Group II. Cardiac output and organ blood flow did not vary significantly in Group I. In Group II, intrapulmonary epinephrine significantly improved blood flow to the myocardium, the brain, and the adrenal glands. A mean myocardial blood flow of less than 0.13 …

Theoretical Advantages Of Abdominal Counterpulsation In Cpr As Demonstrated In A Simple Electrical Model Of The Circulation, Charles F. Babbs, Sandra H. Ralston, Leslie A. Geddes

Weldon School of Biomedical Engineering Faculty Publications

Animal studies and preliminary clinical observations suggest that the addition of interposed abdominal compressions (IAC) to ventilation and chest compression of standard cardiopulmonary resuscitation (CPR) augments blood flow, blood pressures, and immediate survival. To investigate the physical basis for enhanced circulation during IAC-CPR, we developed an electrical model of the circulation. Heart and blood vessels were modeled as resistive-capacitive networks, pressures as voltages, blood flow as electric current, blood inertia as inductance, and the cardiac and venous valves as diodes. External pressurization of the heart and great vessels, as would occur in CPR, was simulated by application by half-sinusoidal voltage …

Efficacy And Safety Of The Reciprocal Pulse Defibrillator Current Waveform, M J. Niebauer, Charles F. Babbs, L A. Geddes, J D. Bourland

Weldon School of Biomedical Engineering Faculty Publications

The efficacy and safety of a new defibrillating current waveform, consisting of a low-tilt 5 ms trapezoidal pulse followed closely by a second identical pulse of opposite polarity, was tested m seven isolated, perfused, working canine hearts suspended in an isoresistive, isosmotic shock bath at 37 oC. The efficacy and safety of the reciprocal pulse was compared with a single 5 ms pulse, a single 10 ms pulse, and a dual (unidirectional) 5 ms pulse waveform. The mean threshold average current densities for the 5 ms single pulse, 10 ms single pulse, dual 5 ms pulse, and reciprocal pulse (absolute …

Indiana Highway Cost-Allocation Study, Kumares C. Sinha, Tien Fang Fwa, Essam Abdel-Aziz Sharaf, Ah Beng Tee, Harold L. Michael

JTRP Technical Reports

No abstract provided.

Street Cuts In County And City Streets, James Mabry Iddins

Indiana Local Technical Assistance Program (LTAP) Technical Reports

This report presents a detailed study of the methods and procedures used by county and city engineers to control street cuts.

Street Cuts In County And City Streets, James Mabry Iddins

Indiana Local Technical Assistance Program (LTAP) Publications

This report presents a detailed study of the methods and procedures used by county and city engineers to control street cuts.

A Checklist And Sample Specifications For Front End Loaders, Herpicc

Indiana Local Technical Assistance Program (LTAP) Publications

Attached is a checklist and sample specifications for purchasing front end loaders for use in the maintenance of Indiana's local roads and streets.

This checklist and the sample specifications provide for individual preferences. They are not intended to dictate decisions or restrict bidding. If followed, they will assure a durable piece of maintenance equipment well suited for the uses placed on front end loaders by Indiana Counties, Cities and Towns.

A general observation of those with experience is that reducing specification requirements to obtain a lower first cost is nearly always a poor economic decision.

Field Evaluation Of An Impact Testing Device For Measuring Base Course Strength, Norman W. Garrick

Indiana Local Technical Assistance Program (LTAP) Publications

This publication documents the factors that affect the use of the Clegg Impact Tester, for measuring in-situ, the load-carrying capacity of unpaved low-volume roads and to assess the suitability of this device for that purpose and to initiate the development of guidelines for its use.

Revenue Calculations Pertaining To A Change In County Local-Option Highway-User Taxes Proposed By The Indiana Association Of County Commissioners, Association Of Indiana Counties, And Indiana Association Of Cities And Towns, Herpicc

Indiana Local Technical Assistance Program (LTAP) Publications

The projected revenue values contained in this report are the product of computer programs developed by staff members of the Highway and Extension Research Project for Indiana Counties and Cities (HERPICC). In its role as provider of technical information to the state's counties and municipalities, HERPICC produced this report in response to a request from the three associations who, as representatives of local governments, proposed the changes analyzed herein. Given its status as a state agency, HERPICC'S production of this report is not intended to represent, nor should it be interpreted as, either an endorsement or a criticism of the …

Use Of Peats As Embankment Foundations : Interim Report, Harold Allen Gruen, C. W. Lovell

JTRP Technical Reports

No abstract provided.

An Investigation Of Contract Claims For Indiana Highway Construction Projects, Karen Denise Berg

JTRP Technical Reports

No abstract provided.

Priority Setting Of Highway Improvement Projects, Mark Douglas Harness, Kumares C. Sinha

JTRP Technical Reports

No abstract provided.

Design Of Compacted Clay Embankments For Improved Stability And Settlement Performance : Interim Report, Martin J. Goodman, Jean-Lou Chameau, C. W. Lovell

JTRP Technical Reports

No abstract provided.

Controlling Movement Of Embankments Over Peats And Marls, Harold Allen Gruen, C. W. Lovell

JTRP Technical Reports

No abstract provided.

Indiana State Highway Reciprocity Study, Kumares C. Sinha, Graham S. Toft, Virgil L. Anderson, Essam Abdel-Aziz Sharaf, Kang Hu

JTRP Technical Reports

No abstract provided.

1983 Directory Of Indiana State, County, City And Town Officials Responsible For Road And Street Work, Herpicc

Indiana Local Technical Assistance Program (LTAP) Directory

Contact information for agency officials and employees responsible for Indiana’s local road infrastructure.

A Training Guide For Pavement Maintenance Personnel, Herpicc

Indiana Local Technical Assistance Program (LTAP) Publications

These Guidelines have been prepared as a reference for highway maintenance personnel responsible for patching pavements and are intended as a reference for the patching crew. The Guidelines are not intended to be a detailed reference describing the successes and failures of techniques and materials used by various agencies to construct pavement patches. The patching techniques and materials presented in these Guidelines are those which have been developed by research and successfully used by various agencies to patch highway pavements under various climatic or weather conditions.

Checklist For Preparing Basic Motor Grader (29,000 Lbs. Class) Specifications, Herpicc

Indiana Local Technical Assistance Program (LTAP) Publications

This checklist provides various items to be considered when seeking bids for motor graders.

Effects Of Myocardial Infarction On Catheter Defibrillation Threshold, Charles F. Babbs

Weldon School of Biomedical Engineering Faculty Publications

Because the automatic implantable defibrillator may be used in patients having ischemic heart disease, it is important to know whether myocardial ischemia changes the threshold for ventricular defibrillation under experimental conditions simulating automatic internal defibrillation. We determined changes in ventricular defibrillation threshold following coronary occlusion, using an electrode catheter designed for use with an automatic implantable defibrillator. Acute myocardial ischemia was produced without thoracotomy in 10 dogs (experimental group) by embolization with a plastic bead injected via a catheter into the left coronary artery. A control group of 4 dogs had only saline injected into the artery. Defibrillation threshold was …

Simple Methods For Determining The Accuracy Of Tumor Blood Flow Measurements Using Radioactive Microspheres In Rats, Rosanna C. Chan, Charles F. Babbs, Richard J. Vetter

Weldon School of Biomedical Engineering Faculty Publications

Two simple methods are presented that allow positive identification of the accuracy and precision of the microsphere technique and a quick verification of sphere entrapment in tumor vessels. A known flow of Ringer's solution from a motor-driven syringe is perfused through the rat's isolated systemic circulation from left ventricle to right atrium and collected in a funnel. Using this preparation, total blood flow in rats measured with radioactive microspheres injected into the left ventricle was 97% of actual flow. The coefficient of variation (standard deviation/mean) of the microsphere measurements was 0.22. In the same preparation, non-entrapment of microspheres in subcutaneous …

Improved Oxygen Delivery During Cardiopulmonary Resuscitation With Interposed Abdominal Compressions, William D. Voorhees, Mark J. Niebauer, Charles F. Babbs

Weldon School of Biomedical Engineering Faculty Publications

The ability of a new modification of cardiopulmonary resuscitation (CPR) to deliver oxygen to tissues was evaluated. The method utilizes standard CPR techniques with the addition of manual abdominal compressions (100 mm Hg) interposed between chest compressions, and is termed interposed abdominal compression-CPR (IAC-CPR). Oxygen delivery was measured by a spirometer in a closed circuit designed to permit positive-pressure ventilation synchronized with mechanical chest compression. Ventricular fibrillation was induced electrically in 10 anesthetized dogs. In each dog, trials of IAC-CPR and standard CPR were alternated every five minutes during a 30-minute period. Arterial and central venous blood pressures, oxygen consumption, …

Relationship Of Blood Pressure And Flow During Cpr To Chest Compression Amplitude: Evidence For An Effective Compression Threshold, Charles F. Babbs, W D. Voorhees, K R. Fitzgerald, H R. Holmes, L A. Geddes

Weldon School of Biomedical Engineering Faculty Publications

This study was conducted to investigate the importance of the depth of chest compression in producing effective cardiopulmonary resuscitation (CPR) in animals, as indicated by cardiac output and mean arterial blood pressure. Cardiac output was measured by a modified indicator dilution technique in 8 anesthetized dogs, 6 to 12 kg body weight, during repeated 2-minute episodes of electrically induced ventricular fibrillation and CPR provided by a mechanical chest compressor and ventilator (Thumper^®). Chest compression exceeding a threshold value (x₀) between 1.5 and 3.0 cm was required in each animal to produce measurable cardiac output. In particular, …

A Nondestructive Testing Procedure For In-Place Evaluation Of Flexural Strength Of Concrete : Informational Report, Alvin Sunao Nishikawa

JTRP Technical Reports

No abstract provided.

Polymer Treatment Of Non-Durable Aggregates, Douglas Windslow, William Lee Dolch

JTRP Technical Reports

No abstract provided.

Techniques To Increase Survival Of New Highway Plantings (Seeding Portion), Philip L. Carpenter, John B. Masiunas

JTRP Technical Reports

No abstract provided.

Chemical Mowing: A New Maintenance Concept For Indiana Roadsides : Final Summary Report, D. James Morré

JTRP Technical Reports

No abstract provided.

The Establishment Of Prairie Species Along Roadsides : Interim Report, John B. Masiunas, Philip L. Carpenter

JTRP Technical Reports

No abstract provided.

Classification And Other Standard Tests For Shale Embankments, Michael William Oakland, C. W. Lovell

JTRP Technical Reports

No abstract provided.

Effects Of Fertilization Practices During Nursery Production On Mycorrhizal Development By Landscape Plants Used For Highway Revegetation : Interim Report, Stephen Dunning Verkade

JTRP Technical Reports

No abstract provided.