Acute Heart Failure. Dr. Khaled M. Al-Qudah. 4/24/2013 Dr. Khaled Al-Qudah 1

Transcription

1 Acute Heart Failure Dr. Khaled M. Al-Qudah 4/24/2013 Dr. Khaled Al-Qudah 1

2 Acute heart failure is one of the major causes of sudden death in animals, especially when death is associated with exertion or excitement. 4/24/2013 Dr. Khaled Al-Qudah 2

3 The disease is characterized by: sudden loss of consciousness falling with or without convulsions sever pallor of the m.m death or complete recovery from the episode 4/24/2013 Dr. Khaled Al-Qudah 3

4 Etiology: Severe defect in filling when there is failure of heart to act as a pump due to: 4/24/2013 Dr. Khaled Al-Qudah 4

5 Tachycardia: resulted from Myocardial degeneration falling disease (copper deficiency in cattle) Vit E deficiency (whit muscle disease) electrical or lightning strike. administration of some drugs in large amounts like adrenergic drugs. 4/24/2013 Dr. Khaled Al-Qudah 5

6 Bradycardia: hypoglycemia intravenous injection of calcium administration of xylazine concentrated solution of KCl 4/24/2013 Dr. Khaled Al-Qudah 6

7 Ventricular fibrillation: Lightning strike Plant poisoning Overdose with anesthetics Severe toxemia 4/24/2013 Dr. Khaled Al-Qudah 7

8 Pathogenesis 1. Excessive tachycardia 4/24/2013 Dr. Khaled Al-Qudah 8 decrease in the diastolic period make the filling of the ventricles impossible cardiac out-put is reduced Failure of the heart to act as a pump

9 2. Ventricular fibrillation Incoordinated contraction Decrease in blood ejection from the heart. In severe cases no blood ejected from the heart. 4/24/2013 Dr. Khaled Al-Qudah 9

10 3. Severe Bradycardia decrease in the systolic period make the filling of the ventricles impossible cardiac out-put is reduced Failure of the heart to act as a pump 4/24/2013 Dr. Khaled Al-Qudah 10

11 In all above mentioned circumstances, there is a significant reduction in minute volume of the heart. Severe degree in tissue anoxia. The most sensitive organ is the brain and the first clinical signs are nervous in type. 4/24/2013 Dr. Khaled Al-Qudah 11

12 Acute cases Clinical finding: Sudden death within seconds or minutes. The animal shows some signs through the episode: dyspnea staggering falling death 4/24/2013 Dr. Khaled Al-Qudah 12

13 Acute cases Marked pallor m.m because of the reduction in arterial blood flow. Clonic convulsions. Death accompanied by deep asphyxial gasps 4/24/2013 Dr. Khaled Al-Qudah 13

14 Less acute cases The respiratory distress is more obvious because of pulmonary edema The length of the episode is hours long The syndrome is clinically similar to the acute left sided heart failure. 4/24/2013 Dr. Khaled Al-Qudah 14

15 Treatment: It is not practicable in large animals because of the short course of the disease. Intracardiac injection of very small doses of adrenaline. 4/24/2013 Dr. Khaled Al-Qudah 15

16 Peripheral Circulatory Failure: DR. Khaled M. Al-Qudah 4/24/2013 Dr. Khaled Al-Qudah 16

17 Failure of venous return to the heart caused reducing in the cardiac out-put. 4/24/2013 Dr. Khaled Al-Qudah 17

18 Clinically characterized by: muscle weakness subnormal temperature arterial blood pressure respiratory and heart rate depression mild clonic convulsions in some cases coma 4/24/2013 Dr. Khaled Al-Qudah 18

19 Etiology Hypovolemic failure (haematogenic failure): hemorrhage dehydration 4/24/2013 Dr. Khaled Al-Qudah 19

20 Etiology. Vasogenic failure (distributive failure): severe damage of the body tissues as a result of: trauma extensive surgery burn injury 4/24/2013 Dr. Khaled Al-Qudah 20

21 This will cause vaso-dilitation followed by pooling of the blood in the vessels, which reduce the effective circulating volume. 4/24/2013 Dr. Khaled Al-Qudah 21

22 Clinical Finding: General depression, weakness Subnormal temp. heart rate but the intensity of the heart sounds is reduced. Weak pulse, with small amplitude. Skin is cold and the m.m is pale, with prolonged capillary refill time. 4/24/2013 Dr. Khaled Al-Qudah 22

23 Clinical Finding.. Fast, shallow respiration. Anorexia and thirst. Nervous signs include listlessness coma clonic convulsions in some cases 4/24/2013 Dr. Khaled Al-Qudah 23

24 Treatment The main principle of treatment is to restore the circulation blood volume to normal and avoid tissue anoxia. 1). In acute hemorrhage which reduce the PCV to less than 20% requires intensive monitoring and fluid replacement. When the PCV falls below 12% blood replacement is essential 4/24/2013 Dr. Khaled Al-Qudah 24

25 Treatment. 2). Blood or fluid loss that results in total protein concentration below 3.5 g/dl requires plasma or whole blood 3). Peripheral vasoconstructive drugs should be avoided, as they further restrict blood flow and decrease tissue perfusion 4/24/2013 Dr. Khaled Al-Qudah 25

26 Edema Dr. Khaled M. Al-Qudah 4/24/2013 Dr. Khaled Al-Qudah 26

27 Edema is the term generally used for the accumulation of excess fluid in the intercellular tissue spaces or body cavities Edema may be localized or may be systemic 4/24/2013 Dr. Khaled Al-Qudah 27

28 When edema is severe and generalized and causes diffuse swelling of all tissues, it is called Anasarca. Edema fluid in the peritoneal cavity is known as Ascites. in the pleural cavity it is known as Hydrothorax in the pericardial sac is known as Hydropericardium. 4/24/2013 Dr. Khaled Al-Qudah 28

29 Non-inflammatory edema is due to hypoperteinemia (protein poor) where the specific gravity is usually below and is referred to as a transudate. Inflammatory edema is protein-rich (specific gravity is usually over 1.020) and usually contains leukocytes and is referred to as an exudate. 4/24/2013 Dr. Khaled Al-Qudah 29

30 Etiology INCREASED HYDROSTATIC PRESSURE: An increase in hydrostatic pressure in the venular end of the microcirculation raises the filtration pressure and opposes the oncotic pressure of plasma proteins. 4/24/2013 Dr. Khaled Al-Qudah 30

31 Increased Hydrostatic Pressure. C. H. F: When heart failure is right sided, the edema is systemic; when heart failure is left sided, the lungs are primarily affected. 4/24/2013 Dr. Khaled Al-Qudah 31

32 Increased Hydrostatic Pressure. Hepatic fibrosis Portal hypertension edema (ascites) Local compression of mammary veins by large fetus Udder or ventral edema in mares and cows in late pregnancy. 4/24/2013 Dr. Khaled Al-Qudah 32

33 DECREASED PLASMA OSMOTIC PRESSURE: Since albumin is the primary osmotic force responsible for reabsorption of interstitial fluid, a significant reduction of this protein results in edema. In most circumstances, the critical level of plasma protein is about 2.5 gm/dl. 4/24/2013 Dr. Khaled Al-Qudah 33

34 DECREASED PLASMA OSMOTIC PRESSURE Endoparasitism [ strongylus sp.] In horse [ fasciola sp. [ Bunostomum. Sp.] in cattle and sheep [ Haemonchus. Sp. 4/24/2013 Dr. Khaled Al-Qudah 34

35 DECREASED PLASMA OSMOTIC PRESSURE Renal diseases. damage to the glomeruli leads to massive proteinuria. Severe liver disease, reduced synthesis of plasma proteins. 4/24/2013 Dr. Khaled Al-Qudah 35

36 DECREASED PLASMA OSMOTIC PRESSURE Malnutrition with diets low in protein. Protein-losing gastroenteriopathies: John s disease Heavy infestation with Ostertagia sp. in young cattle 4/24/2013 Dr. Khaled Al-Qudah 36

37 OBSTRUCTION OF LYMPHATIC FLOW Interference with lymphatic drainage is the cause for expansion of the interstitial fluid volume. This type of edema is usually restricted to a localized area drained by a lymph node. 4/24/2013 Dr. Khaled Al-Qudah 37

38 OBSTRUCTION OF LYMPHATIC FLOW.. Tumors, Lymphosarcoma Inflammation Congenital: inherited lymphatic obstruction edema in Ayrshire calves. Sporadic lymphangitis in horses 4/24/2013 Dr. Khaled Al-Qudah 38

39 VASCULAR DAMAGE TO SMALL VESSELS: Allergic edema, caused by local liberation of vasodilators: Urticaria Angioneurotic edema (endogenous or exogenous allergens provoke either local or diffuse lesions, especially when the pasture is in flower). Release of Histamine local vascular dilatation with damage to capillary walls leakage of plasma & edema (perineum &udder) conjunctiva. 4/24/2013 Dr. Khaled Al-Qudah 39

40 Purpura hemorrhagica: allergic reaction to streptococcal protein, causing damage to capillary wall and edema. (Face, muzzle, legs) 4/24/2013 Dr. Khaled Al-Qudah 40

41 Toxic damage: Anthrax Malignant edema Gut edema Mulberry heart disease Viral arteritis E. I. A Heartwater I/V Ivermectin ( horses) Plant poisons 4/24/2013 Dr. Khaled Al-Qudah 41

42 Clinical Findings: Anasarca accumulation of edematous transudate in S/Q tissue Ascites accumulation of edematous transudate in the peritoneal cavity: 1. Distention of the abdomen 2. Fluid can be detected by a fluid thrill on tactile percussion and paracentesis. 4/24/2013 Dr. Khaled Al-Qudah 42

43 Clinical Findings. Hydrothorax and hydropericardium, characterized clinically by: 1. Restriction of cardiac movements 2. Embarrassment of respiration 3. Collapse of the ventral parts of the lung 4. Muffling of respiratory and cardiac sounds. 4/24/2013 Dr. Khaled Al-Qudah 43

44 Clinical Findings. Edema of the limbs uncommon in cattle and sheep but occurs in horses Edema of the head in horses is a common lesion in: African horse sickness Purpura hemorrhagica 4/24/2013 Dr. Khaled Al-Qudah 44

45 Horse with ventral abdominal oedema 4/24/2013 Dr. Khaled Al-Qudah 45

46 corneal oedema in a dog 4/24/2013 Dr. Khaled Al-Qudah 46

47 Swelled head in a ram caused by Clostridium novyi 4/24/2013 Dr. Khaled Al-Qudah 47

48 Clinical Findings. Edematous swelling ere: Soft Painless Pit in pressure 4/24/2013 Dr. Khaled Al-Qudah 48

49 Clinical Findings. Clinical Significance of Edema is dependent primarily on the location of edema accumulation. Edema of the brain or lungs is a life-threatening condition. Subcutaneous edema and edema of the other viscera have little function significance. 4/24/2013 Dr. Khaled Al-Qudah 49

50 4/24/2013 Dr. Khaled Al-Qudah 50

51 Clinical Pathology: Type of fluid Type of cells: inflammatory cell neoplastic cells Protein content of the fluid will vary according to the cause of edema. 4/24/2013 Dr. Khaled Al-Qudah 51

52 Differential Diagnosis: Ruptures of the urethra or bladder as a result of urethral obstruction by calculus causing accumulation of the urine in the peritoneal cavity and S/Q. 4/24/2013 Dr. Khaled Al-Qudah 52

53 Differential Diagnosis Peritonitis, Pleurisy and Pericarditis are also characterized by local accumulation of fluid but toxemia and signs of inflammation are usually present. 4/24/2013 Dr. Khaled Al-Qudah 53

54 Diagnosis: Paracentesis Nature of the fluid Inflammation Type of inflammatory cells Number of inflammatory cells Yes/No - isolat. Bacteria 4/24/2013 Dr. Khaled Al-Qudah 54

55 Diagnosis. Hypoproteinemia Total serum protein concentration Renal amyloidosis Marked proteinuria Liver diseases Liver test function 4/24/2013 Dr. Khaled Al-Qudah 55

56 Treatment: Correcting the primary disease. H. F. digoxin Pericarditis drainage of the pericardial sac. Parasitic gastroenteritis anthelmintic Hypoproteinemia administration of plasma or plasma substitutes and the feeding of high quality protein. 4/24/2013 Dr. Khaled Al-Qudah 56

57 Treatment. Restriction of the amount of salt in the diet. Diuretics Aspiration of fluids: must be carried out slowly to avoid acute dilatation of splanchnic vessels and subsequent peripheral circulatory failure. This technique gives only temporary relief because the fluid rapidly accumulates again. 4/24/2013 Dr. Khaled Al-Qudah 57