Medical Surgical Nursing PDF

STARS NKL SERVICES & CONSULTANCY ONLINE REVIEW MEDICAL SURGICAL NURSING MODULE#11-1  MEDICAL SURGICAL NURSING REVIEW NOTES AND PRACTICE TEST PART-I REVIEW NOTES...

STARS NKL SERVICES & CONSULTANCY ONLINE REVIEW MEDICAL SURGICAL NURSING MODULE#11-1  MEDICAL SURGICAL NURSING REVIEW NOTES AND PRACTICE TEST PART-I REVIEW NOTES CARDIOVASCULARY SYSTEM DISORDERS Anatomy and Physiology Cardiovascular Physiology  Circulatory system – includes a pump (the heart), interconnected tubes (blood vessels or vascular system), and extracellular fluid and cells (blood) Heart and heart wall layers  The heart is located in the left side of the mediastinum. The Layers of the Heart Wall Epicardium – Essential layer of the heart – The layer that covers the heart is the (visceral – Coronary arteries are found in this layer PERICARDIUM pericardium) – There are two parts- parietal and – Middle and thickest layer of the heart visceral pericardium Myocardium (CBQ) – The space between the two – Responsible for contraction of the heart pericardial layers is the pericardial space – Innermost layer of the heart Endocardium – Lines the inside of the myocardium – Covers the heart valves Chambers of heart Right atrium: collecting chamber for incoming systemic venous system Right ventricle: propels blood into pulmonary system Left atrium: collects blood from pulmonary venous system 1  Left ventricle: largest thick-walled muscle that acts as a high-pressure pump which propels blood into the systemic arterial system The heart chambers are guarded by valves - The atrio-ventricular valves- Tricuspid and bicuspid - The semi-lunar valves- Pulmonic and aortic valves The Blood supply of the heart comes from the Coronary arteries - Right coronary artery - Left coronary artery Blood supply for the heart: Coronary arteries – supply blood to myocardium Coronary blood flow – blood flowing through the coronary arteries Coronary sinus – drainage area for the blood; empties into right atrium The main functions of this system are: - to transport oxygen, hormones and nutrients to the tissues - and to transport waste products to the lungs and kidneys for excretion The CONDUCTING SYSTEM OF THE HEART Consists of the 1. SA node- the pacemaker 2. AV node- slowest conduction 3. Bundle of His – branches into the Right and the Left bundle branch 4. Purkinje fibers- fastest conduction The Heart sounds 1. S1- due to closure of the AV valves 2. S2- due to the closure of the semi-lunar valves 3. S3- due to increased ventricular filling 4. S4- due to forceful atrial contraction 2 Heart rate - Normal range is 60-100 beats per minute - Tachycardia is greater than 100 bpm - Bradycardia is less than 60 bpm - Sympathetic system INCREASES HR - Parasympathetic system (Vagus) DECREASES HR (CBQ) The Heart: Physiology - The amount of blood the heart pumps out in each beat is called theSTROKE VOLUME - When this volume is multiplied by the number of heart beat in a minute (heart rate), it becomes theCARDIAC OUTPUT - When the Cardiac Output is multiplied by the Total Peripheral Resistance, it becomes theBLOOD PRESSURE Blood pressure = Cardiac output X Peripheral resistance Blood pressure - Control is neural (central and peripheral) and hormonal - Baroreceptors in the carotid and aorta - Hormones - ADH, Adrenergic hormones, Aldosterone and ANF The Heart: Physiology - The PRELOAD is the degree of stretching of the heart muscle when it is filled-up with blood - The AFTERLOAD is the resistance to which the heart must pump to eject the blood Vascular System - The vascular system consists of the arteries, veins and capillaries - The arteries are vessels that carry blood away from the heart to the periphery - The veins are the vessels that carry blood to the heart - The capillaries are lined with squamos cells, they connect the veins and arteries 3  - The lymphatic system also is part of the vascular system and the function of this system is to collect the extravasated fluid from the tissues and returns it to the blood Cardiac Assessment 1. Health History - Obtain description of present illness and the chief complaint - Chest pain, SOB, Edema, etc. - Assess risk factors 2. Physical examination - Vital signs- BP, PP, MAP 2 x diastolic + systolic /3 - Inspection of the skin - Inspection of the thorax - Palpation of the PMI, pulses - Auscultation of the heart sounds 4 3. Laboratory and diagnostic studies - CBC - Cardiac catheterization - Lipid profile - arteriography - Cardiac enzymes and proteins - CXR - CVP - ECG - Holter monitoring - Exercise ECG Laboratory Test Rationale - To assist in diagnosing MI - To identify abnormalities - To assess inflammation - To determine baseline value - To monitor serum level of medications - To assess the effects of medication CK- MB (creatine kinase) - Indicates myocardial damage - Elevates in MI within 4-6 hours - peaks in 18 hours and then declines till 3 days - 0-5% of total CK (26-174U/L) - Normal value is 0-7 U/L Lactate Dehydrogenase (LDH) - Elevates in MI in 24 hours - peaks in 48-72 hours - Normally LDH1 is greater than LDH2 - MI- LDH2 greater than LDH1 (flipped LDH pattern) - Normal value is 70-200 IU/L Myoglobin - Oxygen binding protein - Found in both skeletal and cardiac - Level rises 1 hour after cell death - Peaks in 4-6 hours - Returns to normal w/in 24-36 hours - Not used alone - Muscular and RENAL disease can have elevated myoglobin Troponin I and T - Troponin I has a high affinity for myocardial injury - Elevates within 3-4 hours, peaks in 4-24 hours and persists for 7 days to 3 weeks! - Troponin I -