topography of the cardiovascular respiratory tract

If we want to listen to the heart and lungs where do we listen?

Caudal to triceps and forelimb

What is the costochondral junction?

Where bone and cartilage meet

What happens when the animal breathes in?

Diaphragm flattens and moves caudally and increase space in thorax

What is the cardiac notch?

Indent in lung where heart sits

Whats A?

Cardiac notch

Whats B?

Costochondral junction

During a heart sound auscultation, what are the different valves we can listen to?

Pulmonary

Aortic

Mitral

Where is the loudest heart beat that you can hear?

Place stethoscope on thorax dorsal to point of elbow on left hand side

Stethoscope will be positioned over maximum

Which is inspiration which is expiration?

Red = expiration

Blue = inspiration

Whats A?

Pulmonary trunk

Whats B?

Right valve

Whats C?

Base of heart

Whats D?

Intraventricular arteries and veins

Whats E?

Atrium

Whats F?

Aorta leaving heart

Whats G?

Left ventricle

What’s H?

Heart

Whats I?

Apex of heart

Whats J?

Diaphragm

Whats K?

Phrenic nerve

Why do the lungs appear dark?

Lungs full of air

Whats C?

Trachea/windpipe

Whats D?

Aorta

Whats E?

Pairs of ribs

What’s F?

Caudal vena cava

Whats G?

Diaphragm

What’s H?

Abdominal contents

Whats I?

Heart

Why is it opaque at A?

Opaque region where major vessels entering and exiting

Whats B?

Caudal vena cava

Why is it white at C?

Whiter due to dense viscer eg liver

Whats D?

Diaphragm

Doming forwards, meet apex of heart on expiration, flatten when expire

Whats at E?

Where lungs sit

Whats F?

Apex

Whats G?

Heart

Whats A?

Central tendon

Whats B?

Holes, where structures pass

Whats C?

Where aorta passes (dorsal to diaphragm)

Whats D?

Muscular part of diaphragm

What does the muscular part of the diaphragm do ?

Can cause contraction of diaphragm , flattening diaphragm to draw air into lungs

What structure is this ?

Diaphragm

Why do we want the aorta to pass dorsal to the diaphragm?

Important so that when diaphragm contracts aorta doesnt become restricted by muscle

Don’t want blood flow through when aorta is constricted

Whats A?

Vagus nerve

What is B (what connects the sympathetic trunk to the vagus nerve)?

Antis of clavier

(unsure on spelling)

Whats C?

Phrenic nerve

Whats D?

Vertebral bodies

Whats E?

Sympathetic trunk

What would happen if an animal were to break their neck cranial to the 5th+7th division of the cervical spinal cord?

If an animal breaks their neck cranial to this region, inhibits motor function to the phrenic nerves so animal wont be able to breathe

What is the pathway of parasympathetic and sympathetic through the thorax?

Parasympathetic down from head

Sympathetic coming out of thoracolumbar region of spinal cord to supply thorax, abdomen and some of the head

What is the triangle of auscultation?

Where lungs closest to surface and easiest to hear

How would we know if an animal is healthy from an auscultation?

We don’t want to hear much, only ‘gentle breeze’ if disease, wheeze/crackles

Where is the triangle of auscultation?

Draw line caudal to triceps to point of elbow then from penultimate rib forwards to top of scapula then connect triangle

How can we measure respiratory rate just from looking?

Can be watched by seeing flank rise and fall, first part of clinical exam

Then listen to lungs, see if any congestion within airways or build up of fluid / blood - muffled sounds

Why wouldn’t we be able to hear the lungs in the region of the scapula?

Won’t hear anything here as the tricep muscle is covering , as cranial most part of the forelimb is very dense