cardiac and respiratory system

The Cardiovascular System • Consists of: 1. Heart 2. Blood Vessels 3. Lymph system – lymph vessels, lymph nodes, spleen The Cardiovascular System • Functions: – Heart and blood - transport: 1. Oxygen (O2), carbon dioxide (CO2) 2. Nutrients 3. Hormones – Lymph - protects body by eliminating waste and supporting immune system Circulation of Blood • Systemic: (pertaining to the BODY ) – From left ventricle of heart – Carries oxygenated blood to all organs/tissues – Back to right atrium of heart Circulation of Blood • Pulmonary: (pertaining to the LUNGS ) – From right ventricle of heart – Carries deoxygenated blood through lungs – Back to left atrium of heart Blood Vessels • Arteries • (small arteries = arterioles) – Carry OXYGENATED blood from heart to tissues • Exception: pulmonary artery carries deoxygenated blood from heart to lungs – Thick walls with smooth muscle • HIGHER pressure Important Arteries • Aorta – Clinical significance: aortic stenosis (narrowing) • Facial a. – Pulse in horse – Blood pressure Important Arteries • Carotid a. – Deep to jugular vein • Femoral a. – Clinical significance: take your cat/dogs pulse here Blood Vessels • Capillaries – Microscopic – Connect ARTERIES to VEINS – Permeable – exchange of gasses and nutrients Clinical Significance • Capillary refill time Blood Vessels • Veins – (small veins = venules) – Carry DEOXYGENATED blood from tissues to heart • Exception: pulmonary veins carry oxygenated blood from lungs to heart – Thin walls (can look collapsed) with NO smooth muscle • LOWER pressure • Veins, continued – Blue appearance = deoxygenated blood – Closer to surface of skin – Have valves to ensure ONE-WAY flow of blood Important Veins • Jugular v. – Venipuncture or intravenous injections in large and small animals • Cephalic v. – Venipuncture or intravenous injections in small animals • Portal v. The Heart • Function: pump blood throughout the body • Heart rate: • Varies by species (whale 30 bpm, hamster 450 bpm) • Human: 60-80 beats/minute = about 100,800 per day – Size: • Also varies • Normal horse: 8-9 pounds • Secretariat: 22 pounds Apex Base Exterior Structures Left Auricle Right Auricle caudal cranial pulmonary trunk interventricular groove Interior Structures Cranial vena cava Caudal vena cava Right atrium Cranial Caudal (Left AV valve, bicuspid valve) (Right AV valve) (Semilunar) (Semilunar) Ventricular Structures Papillary mm. Chordae tendinae • Papillary muscles: attach chordae tendinae to ventricle wall • Chordae tendinae: Function: prevent prolapse of valves and ensure one-way flow Clinical Significance: Heart murmurs • Turbulent blood flow through valves • Many causes • Sometimes bad, sometimes not Cranial vena cava Caudal vena cava Blood flow through the heart • Deoxygenated blood comes back to the heart from the: – Head via the cranial vena cava – Rest of the body via the caudal vena cava • Enters into the right atrium • Goes through the tricuspid or right AV valve to the right ventricle • From the right ventricle it goes through the pulmonary (semilunar) valve into the pulmonary artery and into the lungs where it picks up oxygen • From the lungs the blood (now oxygenated) comes back to the heart via the pulmonary veins • It enters into the left atrium • Goes through the mitral or left AV valve to the left ventricle • From left ventricle it goes through the aortic (semilunar) valve and to the rest of the body The Lymph System • Lymph vessels • Major lymph nodes • Spleen Major lymph nodes The Spleen • Located on left side of body • Goat: attached to rumen/diaphragm • Largest lymph organ in body • Functions: – Stores red blood cells and iron – Produces lymphocytes (immune cells) – Destroys old red blood cells The Spleen - Goat The Respiratory System ANSC 2202 Inspire: to encourage someone to greater effort, enthusiasm or creativity Latin – inspirare = “to breath” Functions 1. 2. 3. 4. 5. 6. Respiration: Exchange oxygen (O2) for carbon dioxide (CO2) Warm the air Filter foreign particles with mucus and cilia Phonation Olfaction Heat regulation • Inspiration = breathing in – LOWER pressure in lungs – Muscles: 1. Diaphragm 2. External intercostals • Expiration = breathing out – Usually passive – Elastic recoil – Muscles: 1. internal intercostals 2. abdominal muscles – only used when illness causes dyspnea (labored breathing) Functions #2 and 3: Warm the air and filter particles The Upper Respiratory Tract (URT) 1. External Structures 2. Internal Structures (URT) • External 1. Nose 2. = nostrils 3. Nares Philtrum URT • Internal – Nasal cavity – separated by nasal septum • Rostral - Vestibule • Middle = thin scrolls of bone = passages between conchae Concha(e) Meatus(es) Clinical Significance: Atrophic Rhinitis • Young pigs • Two bacteria working together – Pasteurella multocida – Bordetella bronchiseptica • Sneezing, coughing, inflammation of nasolacrimal duct, sometimes hemorrhage • Controlled by vaccination URT • Internal – Nasal cavity – separated by nasal septum • Caudal – – More bony scrolls – Horses – very vascular, be careful when passing nasogastric tube ethmoturbinates URT • Internal – Pharynx (more next week) – Guttural pouches • horses only – Larynx Guttural Pouches • Horses • Diverticulum (blind sac) coming off eustachian tube • Clinical significance: can harbor bacteria Function #4: Phonation – The Larynx Function #5: Olfaction • Sense of smell Function #6: Heat Regulation The Lower Respiratory Tract (LRT) • Consists of: – Trachea – Bronchial tree – Lungs – Pleural membranes • “Windpipe” • Extends from larynx to 5th thoracic vertebrae • Made up of cartilage rings – 16-20 – Semicircular (except birds – they are complete rings) The Trachea • Two parts: 1. Cervical • larynx to thoracic inlet 2. Thoracic • thoracic inlet to bifurcation Tracheal Bifurcation Where trachea splits into primary bronchi The Tracheal Bronchus and Branch off of trachea the bifurcation Ventilates (brings air to) right cranial lung lobe PIGS RUMINANTS BEFORE The Bronchial Tree – Primary or main bronchus (right and left) – Bronchus (plural = bronchi) – Bronchioles – no more cartilage – Alveoli - gas exchange • Microscopic Clinical Significance: Diseases • Pneumonia • Abscesses • Tuberculosis • Melanoma Collapsing Trachea • Small/toy breed dogs • Middle-aged or older • Weak tracheal rings cause collapse Terms for Cardiovascular System Apex Base Right auricle Left auricle Cranial vena cava Caudal vena cava Pulmonary trunk (can also called pulmonary artery) Pulmonary veins Aorta Interventricular groove Right atrium Right ventricle Left atrium Left ventricle Chordae tendinae Papillary muscles Right AV valve (AKA tricuspid) Left AV valve (AKA mitral or bicuspid) Aortic valve (AKA aortic semilunar valve) Pulmonary valve (AKA pulmonary semilunar valve) Pericardial sac Jugular vein Cephalic vein Spleen Lymph nodes (see picture in lecture notes) Terms for Respiratory System Nares Philtrum Guttural pouches (equine only; be able to identify on picture) Larynx Epiglottis Arytenoid Cartilage Trachea Tracheal bronchus Tracheal bifurcation Diaphragm Lungs Alveoli (be able to identify on picture) The Spleen – Horse • Clinical significance: – Horses: contracts when stressed, cause of colic – Dogs: cancer Lungs Oxygenated blood Deoxygenated bloo