Syllabus

UCSD Cardiovascular Animal Laboratory

Lab I, II, III

Winter Quarter, 1999

I . Introduction

Here is the physiology faculty's explanation, in their own words, of the value of dog vivisection.

Laboratories using animals have been an integral part of the teaching of Physiology at UCSD since the School began in 1968. The course faculty believe that direct exposure to the cardiovascular system, by studying anesthetized, open- chest, living animals, provides a deeper understanding than can come from textbook study, lectures, films or computer simulations alone.

Students will not only directly observe the process of normal integrative physiology, extending and reinforcing core material, but they also will examine how these normal physiologic processes are changed by myocardial ischemia cardiac arrhythmias, and a variety of pharmacological agents which they will administer to patients later in their careers.

At no other time during medical school training will the student be able to see and feel physiological process in the manner provided by this laboratory. The experience is unique, and we believe, irreplaceable in the complete education of physicians.

The major objectives of the Cardiology Laboratory are:

1. Discuss the cardiac cycle and intracardiac pressure measurements utilizing the Swan-Ganz catheter.

2. Determine and discuss the effects of sympathetic and parasympathetic agonists.

3. Analyze the effects of atrial and ventricular pacing.

4. Examine the hemodynamics of obstructive lesions using pulmonary stenosis as a model.

5. Determine and discuss the effects of sympathetic antagonists.

6. Observe the electrical and mechanical alterations produced by cardiac ischemia.

7. Observe technique of defibrillation.

8. Examine gross anatomy by dissecting the heart at the end of the experiment with your instructor.

The following syllabus covers nine typed pages.

II. Preparation of the Animal and the Recording System

The students are advised to watch a videotape on "surgical procedures" such as IV placement prior to attending the lab. One student told me the video, which is several years old, shows the director of this course vivisecting without gloves. The dogs are already sedated, intubated, and restrained when the students enter, so they never see the dogs active and alert. They are cautioned to contact one of the circulating staff if at anytime they feel the animal needs more anesthetic.

A. FEMORAL ARTERY AND VEIN CANNULATION

The printed instructions for placing an IV in the dog's femoral vein cover one third a page, typed single-spaced, thus revealing the profound inexperience of the operators of this lab. One student told me her dog bled to death during this prepatory phase, so she and her teammates had to watch a different dog's vivisection.

B. JUGULAR VEIN CANNULATION

First-year medical students float a Swan-Ganz catheter.

III. Studies on the Cardiac Cycle

ECG leads are placed.

A. INTRA-ATRIAL PRESSURE

B. VENTRICULAR PRESSURE

C. PULMONARY ARTERY AND PULMONARY CAPILLARY WEDGE PRESSURES

Swan-Ganz used to obtain various pressure tracings.

IV. Pharmacologic Regulation of Cardiac Outpu

May be performed now or after the chest is opened.

Cardiac output measured by thermal dilution. CO and various pressures measured after isoproterenal and after norepinephrine.

V. Open Chest Surgery

Students incise the dog's skin with electrocautery, open his sternum with a bone saw, and place rib spreaders to hold his chest open. Then they open his pericardium and create a "cradle" to hold his beating heart while they proceed with the demonstration. Obviously this is surgery, but no surgeon is present . . .

VI. The Effects of Electrically Induced Alterations in Cardiac Rhythm

A. PREMATURE ATRIAL CONTRACTIONS

B. PREMATURE VENTRICULAR CONTRACTIONS

Students place electrodes on various places on the dog's heart, send an abnormal stimulus, and watch the dog's ECG and pressures change.

VII. Pulmonary Stenosis

Students press their fingertips on to the dog's pulmonary artery, partially occluding it, and watch changes.

VIII. The Effects of Myocardial Ischemia

Young doctors-in-training intentionally ligate the dog's coronary arteries, to produce ECG changes. This is not a technique they will ever use in the ICU.

IX. Cardioversion

The students intentionally induce v-fib so the instructors can defibrillate. Then they stop the dog's heart with KCl and restart it with calcium.

X. Dissection of the Heart

Administer pentobarbital in 10 ml increments until cardiac contraction ceases. Turn off the respirator. Your instructor will help you remove the heart by cutting the great vessels.

No mention of cleanup is made. I imagine a pile of blood-smeared dog corpses with chests splayed open, hearts gone. At roughly 70 pounds a piece, thirty dogs would make a pile the size of a Volkswagen. And weigh about as much too. Twice a year.

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