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245 Cards in this Set
- Front
- Back
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The pleura within the chest primary function is to:
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prevent friction in chest cavity due to movement of lungs
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The motor nerves to the diaphragm are called the
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Phrenic nerves
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CLINICAL-Damage to neck region may damage the phrenic nerve and will result in ____________ due to the diaphragm no longer getting the appropriate nerve impulses.
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the inability to breath
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A diaphragmatic hernia is one in which the organs of the abdominal cavity protrude into the thoracic cavity through the diaphragm and this results in:
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difficulty breathing due to extra pressure within the chest and the diaphragm possibly not functioning as efficiently as possible.
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CLINICAL--PE of a pt w/a hernia will reveal:
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Muffled heart sounds on the side of the hernia with gut sounds in the chest. Easily repaired w/Sx
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Irritation of lungs trachea, bronchial tubes, stimulates the __________ which results in coughing.
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X Vagus nerve
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The mediastinum is
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The mediastinum is the "middle" section of the chest cavity that contains all of the chest organs except the lungs.. The chest cavity contains the left and right lungs, which lie on either side of the heart.
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One function of the mediastinum is to
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divide the Right lung from the Left lung and acts as a barrier between them to keep injury or infection in one from affecting the other.
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Pulmonary compliance refers to
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Elastic ability of lungs to stretch and recoil during breathing. Low compliance indicates a stiff lung and means extra work is required to bring in a normal volume of air. This occurs as the lungs in this case become fibrotic, lose their distensibility and become stiffer. In a highly compliant lung, as in emphysema, the elastic tissue has been damaged, usually due to their being overstretched by chronic coughing. Patients with emphysema have a very high lung compliance due to the poor elastic recoil, they have no problem inflating the lungs but have extreme difficulty exhaling air. In this condition extra work is required to get air out of the lungs.
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Emphysema is a loss of
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pulmonary compliance due to loss of elasticity which makes it difficult to exhale CO2.
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Bronchodialation refers to
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smooth muscles of bronchi relaxing and usually results in better airflow.
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Bronchodialator
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are a substance that dilates the bronchi and bronchioles, decreasing airway resistance and thereby facilitating airflow
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Basic air is how much O2?
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21%
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Basic air is made up of how much Nitrogen?
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78%, which we do not use
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Of the air we breath 21% is O2, 78% N, the 1% left is trace gasses and CO2 in normal air is less than 300 parts per million. Build up of CO2 is
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toxic, one of the most toxic gasses.
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Diffusion is the movement of a gas or solute from
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a HIGHER to a lower concentration. *requires no energy
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Gas exchange: O2 in aveoli where it is highly concentrated diffuses to the
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capillaries of the lungs, an area of lower concentration.
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Gas Exchange: CO2 moves from capillaries where it is highly concentrated to the
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lungs, where it has a low concentration, and is then expelled.
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What is the interpleural space?
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It is the space within the thoracic cavity walls and the organs contained within.
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The interpleural space MUST be_________ in order for lungs to function.
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under negative pressure ( a vacuum)
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The interpleural space is also known as____________________
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the mediastinum.
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What stimulates the respiratory rate?
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CO2 levels stimulate the pneumotaxic center and then the phrenic nerves.
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Inspiration is an active process and therefore requires ___________ whereas expiration is a passive process an does not.
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energy
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The bronchioles of the respiratory tract is lined with what type skin cells?
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Pseudostratified columnar epithelium
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The MCTS, Mucocilliary Transport System, is very vascular and its function is ______________________ _______________________________
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to trap dust, particles, foreign bodies in air and with the aid of mucous, traps it all and moves it out. Also keeps cells within the respiratory system moist so they do not rupture.
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Mast cells are a part of the layer of tissue located under the tissue lining respiratory tract and have as a function:_________________________ ________________________________
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their rupture releases histamines causing the the symptoms related to allergies such as the hypersecretion of mucous.
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What are the 2 primary functions of the respiratory tract?
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1) Gas exchange in alveolar sacs 2) Regulates blood ph along with kidneys
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CO2 waste is released from cells, combines with H2O to form H2CO3, carbonic acid, which is responsible for transporting CO2 out of the blood. describe what happens next.
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Once the CO2 combines with H20 to form H2CO3, it moves through the circulatory system to the alveolar sacs where the CO2 moves from the alveolar capillaries to the alveoli and then out of the lungs.
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Increased CO2 levels leads to increased levels of carbonic acid and therefore a higher blood ph and this then leads to the development of ____ _______________________________
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Hyperkalemia which if not treated can lead to cardiac arrest and death.
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Eupnea is a term that means _______ _______________________________
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Normal breathing *avg small animal is 15bpm at rest
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Apnea is a term that means; _______ ________________________________
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cessation of breathing
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Cynosis refers to:
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a bluish coloration of the mucous membranes due to low O2, high CO2 levels
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Atelectasis is a term that refers to:
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Collapse of the lungs where the walls of the alveoli stick together.
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Tidal volume is defined as
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-the volume of air taken in with inhalation -depth of respiration
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We estimate the Tidal volume by:
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the weight of the animal
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What is the Minute Volume and how is it calculated?
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total volume of air moved in a minute (Respiration rate per minute) times (Tidal Volume) equals Minute volume ex----> 15 bpm * 60cc inspiration = 900cc/min
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What is respiratory alkalosis?
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CO2 ↓ →H2CO3 ↓ →blood ph ↑ Increased levels of Carbonic acid in the blood as a result of lower levels of CO2. The low CO2 does not allow for enough of the H2CO3 to be broken down as the CO2 is exhaled.
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The normal ph of the blood is
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7.4 +/- .2
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The etiology of Respiratory Alkalosis is:
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In people---> hyperventilating, anxiety animals---->over breathing for animals under anesthesia Tx is to stop breathing for animal for about 4 minutes (anesthesia apnea)
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Respiratory acidosis is a result of:
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Increased CO2 levels in the blood CO2↑ →H2CO3 ↑ →blood ph↓ → K+↑ → heart rate ↓→cardiac arrest
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What are the etiologies for respiratory acidosis?
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-Atlectasis/ lung collapse -Pyothorax -Hemothorax -Chyothorax -Drowning -Pneumonia -Pulmonary contusion -Pulmonary edema -Emphysema -Obstructed airway -Anesthesia Machine related
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Respiratory acidosis is linked to lung collapse/alveolar collapse because___________ and the most common cause is ______________
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it limits air exchange Pneumothorax due to hole in chest wall and possible a hole in the lung
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CLINICAL-An animal with a collapsed lung will present with
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Cynosis Dyspnea
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CLINICAL-How would an animal with a collapsed lung be treated?
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1) Gauze with Vaseline to STOP airflow into thorax temporarily 2) Thoracocentesis to remove air and reestablish vacuum
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What is pyothorax and how is it treated?
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Pus in the interplural space Tx-thoracocentesis to remove pus and a chest tube is sewn in to keep drainage going Antibiotics
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Why is pyothorax linked to respiratory acidosis?
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Any excess fluids in the interplural space increase the pressure against the lungs making it more difficult for them to fully expand and therefore decreasing respiratory efficiency and increasing CO2 levels result.
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Pleura produces anticoagulant,, so the blood from a hemothorax can be withdrawn and then____________
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autotransfused
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Hydrothorax is water in the thoracic cavity made up of the plasma fraction of blood and is typically caused by ____________________________ ____________________________
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neoplasias on chest wall
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What is Chyothorax?
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accumulation of lymph from the lymphatic system accumulates in the pleural space due to a tear or rupture of thoracic duct that carries lymph from lymph vessels in the mesentary to the thorax.
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When fluid is withdrawn from the chest, it may be difficult to tell if it is pus or lymph. What can you do to differentiate?
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1) Examine under microscope 2) If chilled with ether, lymph will turn clear
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When there are alveolar sac issues, what is the reason for respiratory acidosis?
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diffusion distance increases
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One alveolar sac issue is drowning. What is the standard Tx?
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-Administer concentrated CO2 -Diuretics such as Lasix -Bronchodialators- increase diameter for better O2 diffusion
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Pneumonia is another alveolar sac issue that will cause respiratory acidosis due to _________________ ______________________________
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decreased alveolar function due to being filled with pus/fluid
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Bacterial pneumonia is when bacteria
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infect the lungs which causes a production of pus and mucous.
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Hematogenous means
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originating from the blood, such as in a pneumonia that originate from the blood OR from inhalation. Hematogenous pneumonia is typically much more serious than inhalation.
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The lungs should be quiet when listened to however with pneumonia, they will have a ____________ sound and with emphysema will have a ______________ sound.
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moist rales dry rales
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What is the typical treatment for BACTERIAL pneumonia?
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-Tussive medications to stimulate a productive cough to get the pus /mucous up and out -O2 -Antibiotics via IV or Nebulizer cage
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Viral pneumonia typically DOES NOT cause pus production due to suppressing WBC production. The virally caused inflammation leads to production of
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transudate fluid in the lungs/aveolar sacs and although a different cause, is treated the same as the bacterial pneumonia
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Bacterial pneumonia is when bacteria
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infect the lungs which causes a production of pus and mucous.
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Hematogenous means
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originating from the blood, such as in a pneumonia that originate from the blood OR from inhalation. Hematogenous pneumonia is typically much more serious than inhalation.
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The lungs should be quiet when listened to however with pneumonia, they will have a ____________ sound and with emphysema will have a ______________ sound.
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moist rales dry rales
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What is the typical treatment for BACTERIAL pneumonia?
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-Tussive medications to stimulate a productive cough to get the pus /mucous up and out -O2 -Antibiotics via IV or Nebulizer cage
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Viral pneumonia typically DOES NOT cause pus production due to suppressing WBC production. The virally caused inflammation leads to production of
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transudate fluid in the lungs/aveolar sacs and although a different cause, is treated the same as the bacterial pneumonia- Diuretics, O2, bronchodialators but NO antibiotics
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Pulmonary contusion is a result of blunt trauma to the chest that causes the alveolar sac capillaries to burst and since the alveolar sacs secrete heprin, they do not clot efficiently. This contributes to respiratory acidosis because
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there is a decrease in the efficiency of gas exchange which results in increased CO2 levels.
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Tx for pulmonary contusions is:
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*IV fluids *Bronchodialators *first 48 hrs are critical, once past this mark, prognosis is better. *Monocytes will phagocytize the RBC's
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Another cause of respiratory acidosis is pulmonary edema, which results from water moving from capillaries into alveolar sacs. Pulmonary edema has 3 main causes and they are:
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IV fluid excess electric shock Left heart failure
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What is the result of pulmonary edema caused by iv fluid excess and what species is most prone to this?
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Increases blood pressure and blood volume -can result in death if not recognized and reversed -CATS
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What happens in the event of pulmonary edema resulting from electric shock?
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The reaction to an electric shock is delayed 8-10 hours and the result is the slow leakage of fluids from the capillaries and pulmonary edema. Medical attention is required ASAP after a shock to stop or lessen the effects.
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What is the typical treatment for pulmonary edema caused by electric shock?
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Bronchodiolators Corticosteriods if given immediately will change the electric charge effects and should stop the pulmonary edema from happening
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Left heart failure, LHF, aka Congestive heart failure is a result of
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Left heart valve leaks and pumping is slower and ineffective, which leads to fluids backing up in the lungs and increased BP as the heart works harder to compensate
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CLINICAL- An animal with LHF induced pulmonary edema will present with what symptoms?
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Cynotic Dyspnic Moist rales
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CLINICAL-What is the typical Tx for an animal with pulmonary edema related LHF?
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-Lasix IV -O2 -Bronchodialators -diminish blood volume so heart has less work to do. ----Change in diet is very helpful for this: Low to no sodium diet in addition to daily Lasix meds.
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Emphysema is another health issue that can cause respiratory acidosis and the decrease in gas exchange efficiency is linked to______________ _______________________________
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breakdown of elastic in alveolar sacs
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Emphysema is most common in horses because___________________ and this leads to a condition called__ _______________________________
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they spend so much time in dusty barns Heaves--when is horses compensate for poor gas exchange by trying harder to breath. Leads to hypertrophy of muscles around the abdomen.
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Obstructed airway is another cause of respiratory acidosis due to decreased lung efficiency is attributed to what 3 causes?
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Foreign body ET tube mucous plug during anesthsia Strangulation-acute or chronic due to embedded collar
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An iatrogenic cause of respiratory acidosis is issues related to anesthesia and may be caused by:
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-Trach tube can become plugged with mucous (animal needs retubed quickly) -O2 tank is empty (Always check before surgery) -Soda lime is "used up" and will no longer removing CO2
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Pulmonary compliance refers to
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elasticity of the alveolar sacs and this is decreased in patients with emphysema
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Respiratory rates will go down prior to _____________________ decreasing.
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heart rate
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What is the function of the phrenic nerve?
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It is the motor nerve that innervates the diaphragm.
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What is the function of the diaphragm?
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pushes and pulls air out/in the lungs
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Gas exchange occurs where?
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alveolar sacs
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What is the function of the mediastinum?
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divides the chest cavity and keeps the lungs separate which keeps injury or infection in one lung from affecting the other.
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What is the function of the pleura?
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To protect the thoracic organs from friction so they can function efficiently.
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Each lobe of the lung has 3 things. Name them.
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Bronchi artery vein
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Name the 4 lobes of the right lung
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Apical Cardiac Diaphragmatic Accessory lobe
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The left lung has how many lobes and differs from the right lung in what way?
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3 lobes no accessory lobe
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During inspiration the diaphragm moves__________ and upon expiration, the diaphragm moves _________
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down up
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CO2 is not transported on the RBC as O2 is but is instead in solution in
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the plasma
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Elastic tissue surrounds each alveolar sac which allows for:
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expansion and contraction of alveolar sac
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Alveolar sacs are lined with simple squamous epithelium and has fenestrations that
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allow for air exchange
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Bronchioles are lined with what type of muscle?
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Smooth muscle (along with cartilaginous rings)
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Bronchioles are the _________of the bronchiole tree.
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Smallest
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The base of the heart is the ________ of the heart while the apex is the ___________
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top/most cranial portion bottom/caudal portion
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Pulmonary circulation refers to blood that__________________________
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is on its way to lungs from heart for gas exchange. Low O2 and high CO2 content
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The caudal vena cava brings blood from
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abdomen, rear legs
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The cranial vena cava brings blood from the
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head, front legs
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Systemic circulation comes from the
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Left ventricle to the body via the aorta and is high in O2, low in CO2
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The endocardium and all chambers of the heart, arterys and veins are lined with what type of tissue that helps them avoid friction?
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simple squamous epithelium
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The tricuspid valve of the right side of the heart is made up of 3 parts and the bicuspid is made up of 2 parts that are of ____________
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equal size
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The left ventricle is the most muscular and stronger because it pumps blood throughout the body and in contrast, the right ventricle muscle is
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lesser in size and strength due to only pumping blood to the lungs
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Chordae tendineae are:
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Thread-like bands of fibrous tissue which attach on one end to the edges of the tricuspid and mitral valves of the heart and on the other end to the papillary muscles, small muscles within the heart that serve to anchor the valves.
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Coronary arteries have ___________ over the body for newly oxygenated blood.
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priority
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What are the 3 layers of the heart?
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Endocardium myocardium apicardium
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The pericardial sac produces an ________ to reduce friction.
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an oily fluid
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The right side of the heart/ pulmonary circulation is a ____________blood pressure system.
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low
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The left side of the heart/systemic circulation is a _____________ blood pressure system that pumps the blood throughout the body.
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high
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Valves are made of _________ and SHOULD only __________
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CT open in one direction
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The function of the valves of the heart and veins is to _________________
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insure a unidirectional flow
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The Tricuspid valve is also known as:
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Right Atrial ventricular valve' Right AV valve
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The bicuspid valve is also know as:
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Left atrial valve Left AV valve Mitreal valve
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Flow of blood through the heart:
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Vena cava → Right Atrium →Right AV/Tricuspid valve →Right ventricle →Pulmonary valve →Pulmonary Artery →LUNGS**GAS EXCHANGE** →Pulmonary veins →Left atrium →Left AV/bicuspid valve →Left ventricle →Aortic valve →aorta →cells in body → → →back to vena cava
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When you auscultate the heart, you should
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move around so you can hear all 4 valves in action, which are the sounds you should be hearing --the characteristic lub-dub
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A murmur is general term for an abnormal heart sound resulting from ____________________________________________
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Turbulante blood flow and has a characteristic woooshooing sound
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An arrythemia/dysrythmia is defined as
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dropping of beats from the normal heart rate pattern
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Bradycardia is defined as
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slow heart rate
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Tachycardia us defined as
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a fast heart rate
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Missing more than 3 heart beats will result in______________________
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passing out
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Cardiac output is defined as________ _______________________________ and is calculated by:
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cc's of blood being pumped per minute (Heart rate per minute)*(Stroke volume) equals Cardiac output Stroke volume is amount of blood leaving heart w/each pump ex.REST----> 70bpm*100cc blood =7000cc of blood/minute cardiac output Versus exercise: 170bpm*400cc= 68,000 cc blood/min
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What is used to estimate amount of blood moving through the heart?
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Echocardiogram
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Megacadia is
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the enlargement of the heart due to heart disease an can have right side, left side or both sides involved.
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How much of the heart rate and cardiac output is controlled by the parasympathetic system?
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99.9%
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The sympathetic nervous system only controls the heart rate .1% of the time and this happens only during _____________________________ and this releases _______________
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life threatening situations adrenaline and epinephrine
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The vagus nerve is considered cholinergenic because_____________ ________________________________
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it stimulates the release of ACH (acetocholine)
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The Parasympathetic nervous system via the vagus nerve releases ACH which acts as a_______ to __________ and this effect is counteracted by the release of ________________
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break slow heart rate Atropine
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What is systole?
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The period specifically during which the left ventricle of the heart contracts.
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what is systolic pressure?
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The systolic pressure is specifically the maximum arterial pressure during contraction of the left ventricle of the heart.
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What is diastole?
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The time period when the heart is in a state of relaxation and dilatation and when the chambers of the heart fill (expansion).
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What is diastolic pressure?
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the minimum arterial pressure during relaxation and dilatation of the ventricles of the heart. Diastole is the time when the ventricles fill with blood.
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Blood pressure is defined as
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amount of pressure exerted against walls of aorta when it pumps.
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What is systole?
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The period specifically during which the left ventricle of the heart contracts.
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what is systolic pressure?
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The systolic pressure is specifically the maximum arterial pressure during contraction of the left ventricle of the heart.
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What is diastole?
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The time period when the heart is in a state of relaxation and dilatation and when the chambers of the heart fill (expansion).
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What is diastolic pressure?
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the minimum arterial pressure during relaxation and dilatation of the ventricles of the heart. Diastole is the time when the ventricles fill with blood.
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Blood pressure is defined as
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amount of pressure exerted against walls of aorta when it pumps.
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What is systole?
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The period specifically during which the left ventricle of the heart contracts.
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what is systolic pressure?
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The systolic pressure is specifically the maximum arterial pressure during contraction of the left ventricle of the heart.
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What is diastole?
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The time period when the heart is in a state of relaxation and dilatation and when the chambers of the heart fill (expansion).
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What is diastolic pressure?
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the minimum arterial pressure during relaxation and dilatation of the ventricles of the heart. Diastole is the time when the ventricles fill with blood.
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Blood pressure is defined as
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amount of pressure exerted against walls of aorta when it pumps.
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Normal blood pressure is __________ for both people and animals.
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120/80
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Blood pressure readings of 120/80 represents:
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120 mm hg for ventricular contraction and is The top number, which is also the higher of the two numbers, measures the pressure in the arteries when the heart beats (when the heart muscle contracts). 80 mm hg is The bottom number, which is also the lower of the two numbers, measures the pressure in the arteries between heartbeats (when the heart muscle is resting between beats and refilling with blood).
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What is the blood pressure with the veins?
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3/0
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What is the blood pressure in the right atrium?
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15/0
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What is the blood pressure in the right ventricle?
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25/0
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What is the blood pressure with the pulmonary artery?
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25/15
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What is the blood pressure within the pulmonary vein?
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3/0
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What is the blood pressure within the Left ventricle?
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15/0
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what is the blood pressure within the Left ventricle?
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120/0
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What is the blood pressure within the aorta?
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120/80
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In animal medicine, what do we use for measuring blood pressure rather than a cuff?
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a doppler
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Hypertension is defined as __________ and is _____________ in animals.
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high blood pressure uncommon
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Hypotension is defined as _________ and is _______________
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low blood pressure more of an issue with animals than high BP.
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What are 4 hormones that control the heart rate?
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Epinephrine Cortisol Thyroxin Glucagon
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What effect does epinephrine have on heart rate?
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increase
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Epinephrine is released from ________ in response to____________________
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adrenal glands ACUTE stress
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Cortisol affects the heart rate and is released in response to:
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Chronic Stress, usually environmental in animals Is immunosupressive
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What are 2 of the pathognomic signs of hypothyroidism in dogs?
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Lack of hair on sides and tail
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Thyroxin comes from the thyroid and affects the heart rate when the levels of this hormone are
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excessive
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Thryroxin regulates rate of cell ________________________
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metabolism throughout the body
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Hyperthyroidism is a result of too much_____________ and is called _______________which is rare in most animals, except cats, esp cats over 1o.
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thyroxin T3 & T4 Graves disease
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the Pathognomic sign for Graves disease/hyperthyroidism in cats is
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HR at 250 bpm --tachycardic at rest
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Glucagon increases glucose levels and its effect on the heart is to ______ _______________________________
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increase HR
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Exercise makes the Co2 levels and heart rate go up and what does it do to blood pressure?
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BP goes down as blood moves into dilated vessels and muscles throughout the body.
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Body temperature is another item that can increase heart rate. What are 2 ways temperature goes up?
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*fever due to viral and bacterial infections *Environmental: hypo and hyperthermia
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The Sino-atrial node/ SA Node is located in the right atrium of the heart and its function is
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to act as the electrical pacemaker for the heart by discharging an electrical current to the atria causing them to contract----->Atrial Systole
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The Atrial-Ventricular node is located between the ventricles and Atria of the heart and this
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Acts as an electrical relay station that slows the electrical current before the signal is permitted to pass down through to the ventricles. This delay ensures that the atria have a chance to fully contract before the ventricles are stimulated. --Cause ventricular systole
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What is the function of Purkinje fibers?
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•Relays cardiac impulses to the ventricular cells causing the ventricles to contract.
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What is the role of the "bundles of his"?
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---Transmit electrical impulses of the heart from the sinoatrial (SA) node (pacemaker) located in the right atrium to the rest of the heart. The intrinsic rate of the Bundle of His is between 40 - 60 bpm.[3] The bundle of His branches into the three bundle branches: the right, left anterior and left posterior bundle branches that run along the interventricular septum. The bundles give rise to thin filaments known as Purkinje fibers. These fibers distribute the impulse to the ventricular muscle. Together, the bundle branches and Purkinje network comprise the ventricular conduction system. It takes about 0.03-0.04s for the impulse to travel from the bundle of His to the ventricular muscle.
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If the SA node fails______________
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the AV node will take over and visa versa.
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The P wave on a ECG represents __________________
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Atriole systole--the SA node firing
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An esophageal stethoscope allows you to hear:
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the valves of the heart open and close
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The QRS waves on an ECG represent:
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ventricular systole ---AV node firing
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The T wave on a a ECG represents:
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re-polarization/ resting stage
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PCV, preventricular contraction indicates that
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the myocardium, heart muscle, is not getting enough 02
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The heart muscle has a "golden period". How long is this and what is it?
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6 minutes It represents the amount of time the heart can stop before there are neurological and physiological consequences.
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Cardiac fibrillation is defined as:
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the heart beating in an irregular manner
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Cardiac arrest is defined as:
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The heart has NO eelectrical activity in the myocardium
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What is typically found on a crash cart?
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Predrawn up meds for dealing with heart and respiratory issues -Ambu bag -ET tubes -O2 -EKG machine -defibrillator
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CLINICAL-animal comes into clinic with what appears to be a heart issue. What is the basic procedure?
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-Establish airway-ET tube & bag animal -------Appropriate O2 level to restart heart -Place IV cath --------possibly add sodium bicarb to deal with acidosis -Put EKG leads on ------Determine if it is arrest or fibrillation -Do closed cardiac massage ---------------Compress heart to encourage blood flow to the brain
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Typical Tx for cardiac arrest is:
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Administer epinephrine intracardiac or intra-ET tube to stimulate heart and reestablish heart rate
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With a cardiac fibrillation, the goal for treatment is to convert the irregular heart rhythm back to a normal rhythm by doing what?
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Using electric shock of defibrillation paddles, shocking the heart back into normal rhythm by causing the whole heart (and body) to contract at once. ___Placed on ventral side of abdomen at base & apex of heart.
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What are 5 congenital heart defects discussed in class?
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-Patent Ductus Arteriosis (PDA) -Patent Foramen Ovale-Atrial Septal Defect -Aortic Stenosis -Pulmonic Stenosis -Ventricular septal defect
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What is the function of the Ductus arteriosis in a fetus?
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This carries blood from Vena cava and ride side of heart directly to aorta since the lungs are bi-passed due to receiving O2 in and CO2 being carried out by maternal circulation via placenta and umbilical cord.
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Patent Ductus Arteriosis (PDA) refers to a congentital heart defect where the
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Ductus arteriosis fails to close at birth and the O2 and CO2 blood continue to mix.
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PDA is the most common congenital heart defect which is most commonly diagnosed at 6-8 weeks of age due to what symptoms?
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At the wellness check, owner may mention, and vet and staff may notice, animal is less active. -cynotic gums -Machinary murmur when heart is auscultated--waterfall wooshing sound at base of heart
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PDA Tx:
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Sx is on Tx and this defect is easily closed and should be done ASAP
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What is the function of the Foramen Ovale in the fetus?
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It is an opening in the heart that allows blood to move from Right atria to left atria in addition to circulation via the ductus arteriosis
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Patent Foramen Ovale refers to what congentital heart defect?
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Failure of the foramen ovale to close
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Tx for Patent Foramen Ovale/Atrial Septal defect is:
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Sx to close Heart needs to be stopped ---can use heart lung bypass but animals tend to not do well on these--RBCs tend to rupture & is $$$ --Preferred method is to induce hypOthermia down to 80-85 degrees which will alllow you to stop heart for up to 40 minutes
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Aortic Stenosis refers to when the valve of the aorta
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is constricted and does not allow enough blood flow through leading to blood backing up in the left ventricle. ---this leads to enlargement of left heart ventricle ------>Left heart failure-----> pulmonary edema (backing up of fluids into lungs due to poor circulation)
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Pathognomic sign for left heart failure is:
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Pulmonary edema
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Pathognomic sign for Right heart failure is:
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Ascites
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Pulmonic stenosis is the stenosis of
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the pulmonary valve in right ventricle and Ascites is the typical sign of this problem.
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Ventricular septal defect is a hole _____________ and Tx ___________
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in the septum in the heart depends on degree of hole. May be able to encourage to heal with time and or med....may need surgery.
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Left AV valve insufficiency is an age related "wearing out" of the valves due to the
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shrinkage of the valves made up of CT which then leads to the heart muscle hypertrophy due to needing to work harder to pump blood.
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What are the typical symptoms of Left AV (atrial ventricular) valve insufficiency?
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-Murmur -Pulmonary edema -Higher heart rate -Dyspnic -Hypertrophy of heart can lead to coughing due to heart pressing on trachea
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Left AV valve insufficiency diagnosis is made by:
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-Radiographs -cardiac echo
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Tx for Left AV valve involves:
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-O2 ---->LIFETIME OF MEDS: -Diuretics to reduce water in the lungs--->Lasix is typically used -Reduced sodium diet (Hills h/d) -Digitalis meds to increase hearts ability to contract ----> Digoxin is typical
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Right AV valve insufficiency
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has as a pathognomic sign: Ascites and is treated the same as Left AV valve insufficiency.
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Adult Heartworms tend to live in one place:
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Right ventricle around pulmonary valve
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Obstruction due to heart worms leads to
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Right heart failure leading to ascites
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When diagnosing heart worms, before treating, it is a good idea to:
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try to estimate the degree of infestation with a echocardiogram or ultrasound because large infestations will require Sx to remove adults followed by meds (Carparsilin) to kill microfilaria.
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If an animal has a small infestation of heartworms, then it is possible to treat by:
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meds to kill adults and preventatives to kill microfilaria
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Dead heartworm adults end up where ____________ and have the potential to cause _____________
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lungs via pulmonary arteries VERMINOUS embolism: dead worms stop blood flow in artery which leads to inflammation, abscesses in the lungs---which can rupture and cause bleeding in the lungs
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Vegetative endocarditis is a gram positive infection typically caused by streptococcus. This involves the infection going to the joints and then the left AV valve. Then the body________________________
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-attempts to wall off the infectious bacteria which leads to the buildup of CT on Left AV valves that looks like cauliflower ---this decreases the efficiency of the valve --parts of the "cauliflower" buildup can break off and cause abscesses elsewhere in the body (called a septic embolism)
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Cardiomyopathy is the #1 reason for heart transplants in people and this aquired heart problem involves:
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Autoimmune problem that destroys muscle cells that are then replaced by scar tissue that does not function as heart muscle thereby decreasing pumping efficiency.
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What breed of dogs is cardiomyopathy most common in?
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Dobermans
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Cardiomyopathy can be managed with:
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meds for about a year
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What is a cardiac tamponade?
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A traumatic hole or tumor in the Right Atrium which causes a hole leading to blood flowing into pericardium. --->pressure build within the pericardial sac ----->heart cannot pump efficiently -------->may collapse heart
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What is the Tx for Cardiac tamponade?
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Thoracocentesis to remove blood and possible Sx to repair the hole
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In addition to trauma, cardiac tamponade may be caused by a tumor called a Hemangeosarcoma and this tumor is highly ___________ which gives this condition a ________
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metastatic poor prognosis
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Heart attack and stroke are _________ in animals.
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uncommon
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What is arteriosclerosis?
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Atherosclerosis is a condition in which fatty material collects along the walls of arteries. This fatty material thickens, hardens (forms calcium deposits), and may eventually block the arteries. Atherosclerosis is a type of arteriosclerosis. The two terms are often used to mean the same thing.
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What are some of the pathologies linked with arteriosclerosis?
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-arterial wall plaques--cholesterol deposits -Clot embolism -Myocardial infarction (heart attack) -Cerebral infarction (stroke)
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What is an infarction?
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area of dead tissue due to lack of blood flow
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What is an emboli?
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free floating material in the CVS
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What is an aneurism?
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artery wall thinning out, bulging and eventually rupturing if not treated --rare in small animals ---Seen in horses in anterior/cranial mesenteric artery due to infestation with Strongylus Vulgaris-Equine bloodworm
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What is phlebitis?
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inflammation of veins, typically legs. Important for patients to be up after surgery and walking to encourage circulation in the legs to avoid inflammation and clot formation.
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what are varicose veins?
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veins release clots which tend to lodge in pulmonary arteries causing pulmonary embolism
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Comparison of arterys, veins and capillaries
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fyi
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Although arterys and veins tend to be the same general size, their wall thickness differs how?
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Arteries walls are thicker than the thin walled veins
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Arteries carry blood _______ from heart that is high in________________
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away O2, nutrients
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veins carry blood __________ the heart and this blood is high in _________
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toward CO2 and wastes
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Arteries tend to be located __________ whereas veins tend to be ____________
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deep superficial
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Blood pressure in arteries should be around ___________ whereas in veins it is typically______
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120/80 3/0
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The blood pressure within the capillary beds tends to be around:
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3/0
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What are the 3 mechanisms of venous return?
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#1 is skeletal muscle contraction 2. valves keep blood moving ina unilateral direction 3.Negative interpleural chest pressure from inhaling
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What is shock?
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the venous capillary pooling of blood due to precapillary sphincters all opening at once while post capillary sphincters close ----->Blood thickens due to not circulating and mixing -------->leads to METABOLIC Acidosis
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The artery side of capillaries have the precapillary sphincters that end up staying open while on the venous side of the capillaries, the postcapillary sphincters close, trapping the blood in the capillaries. If the majority of the blood is in capillary beds, the
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rest of the body is not getting the blood it needs because there is NOT enough blood to fill the arteries and the veins in the body all at once.
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How much of the capillaries are typically filled with blood when the body is at rest?
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10%
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What is the function of capillaries?
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Bring O2 and nutrients in from arterys to all the cells in the body and take away wastes and CO2 to the veins.
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What is the general result of capillary pooling?
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Lactic acid goes up CO 2 level goes up H2CO3 goes up ph goes down K goes up
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Hypovalemic shock, the most common type, is attributable to
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ACUTE blood loss ----external injury internal injury to thoracic cavity or abdomen, typically spleen
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Hypovalemic shock signs:
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-pale mucous membranes -tachycardia -hypothermia -BP not easily palpable, weak thready pulse ---LAB -RBC/PCV low -protein low May do Thoracocentesis or abdominocentesis to confirm
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Hypovalemic shock Tx involves:
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-IV cath, possibly 2 open STREAM flow, not drip -Massive amounts of WARMED fluids ----This raises BP and encourage blood flow OUT of capillary beds as does appropriate ph level. -O2 if airway is opne -Raise ph of blood to combat METABOLIC acidosis by adding Sodium bicarbonate --these are followed by a whole blood transfusion
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With hypovalemic shock, once the animal is stabilized, then_____________
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you can proceed to Sx to treat the cause.
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Prolonged shock leads to
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rupture of body cells, then irreversible shock
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With shock, corticosteroids may be given to
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stabilize cell membranes so lysosomes do not rupture cells membranes in response to metabolic acidosis.
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Septic Shock is due to
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septicemia, bacteria, in bloodstream and a typical bacteria is E. Coli which release endotoxins which are a major causal factor in shock
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Septic shock has the same signs as Hypovalemic shock and the treatment is the same with the addition of __________
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antibiotics to treat the infection --Should not use Bacteriocidal drugs because the rupturing/killing of bacteria release MORE endotoxins. ----Bacteriostatic drugs are better due to simply stopping reproduction of bacteria
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Anaphylactic shock is due to ____________, often in reaction to __________________ and the shock is a result of the body _____________
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an allergic reaction medications, especially IV meds releasing massive amounts of histamine
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What is the treatment for Anaphylactic shock?
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Same as hypovalemic shock except will add corticosteroids (better than antihistamines) and Epinephrine
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metabolic acidosis results in:
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Sodium bicarb going down ph going down
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Neurogenic shock is a result of
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neurotic mind overiding some basic brain functions Tx is the same and even though it is a mental shock--still MUST be treated like any other shock. Mainly seen in humans and primates--rarely other animals that lack the developed neocortex.
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Cardiogenic shock is due to :
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Death of heart muscle due to infarction puts off a toxin. Same Tx as HV shock.
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