70 terms

Ch 22 Surg Tech Book

Cardiothoracic Surgery
Sternum(thorax) anatomy
Superior to Inferior
-xiphoid process
12 Ribs
7 true ribs
Connected to the sternum by costal cartilage
Hyaline Cartilage (trachea)
C-shaped rings that prevent trachea from collapsing
Bronchial Division (trachea)
Bronchioles end in alveolar ducts(between the bronchioles
Microscopic air sacs clustered at the end of bronchioles
Hilam (lungs)
Slight concave portion on medial side of each lung where the bronchus
Main Bronchi
Pulmonary arteries
Oxyginated blood leaves the lungs through the pulmonary veins
Pulmonary Veins if the Lungs
-2 from right lobe
-2 from left lobe
Location of Heart
-located within the mediastinum
-2/3 of organ slightly on the left side
Fibrous Pericardium
-heart coverings
-surrounds the heart
-fits loosely around the heart
Parietal Layer
(serous pericardium)
Lines the inside of the fibrous pericardium
Visceral Layer
(serous pericardium)
attached to the surface of the heart
Pericardial Space
(serous pericardium)
Space between the 2 layers that contains pericardial fluid,which acts as a lubricant on the surfaces of 2 layers,reduces friction
Makes up the bulk of the heart wall
Mitral Valve
Also called the bucuspid valve
Chordae Tendineae
-these fibrous cords are attached to the cusps of valves on the ventricle side
-prevent the cusps of the valve from folding back into the atrium
Blood Flow Through the Heart
-rt ventricle pumps blood into pulmonary artery
-lt ventricle pumps to aorta
Circumflex Artery
Supplies blood to left ventricle
The Cardiac Cycle
-includes all physiological actions that occur during a SINGLE heartbeat
Systole:phase of contraction
Diastole:phase of relaxation
Cardiac Conduction
1. SA node
2. AV node
3. Bundle of His
4. Purkinje Fibers
72 beats per minute
Adult normal resting heart rate average
Sinotrial Node
SA node
-located in the right atrial wall inferior to opening of superior vena cava
-"pacemaker" of the heart
Atrioventricular Node
AV node
-impulses from SA node travel here
-the action potential shows at AV node because the fibers are smaller, thus allowing time for the atria to empty blood into the ventricles
Bundle of His (Atrioventricular bundle)
Only electrical current between the atria
Purkinje Fibers
Electrical impulses from Bundle of His enter these conduction fibers
Anatomical Develoment of the Heart
-development begins just before the end of the 3rd week of gestation
Ductis Venosus
A continuation of the umbilical vein
The Ductis Arteriosus
Connects the pulmonary artery with the descending thoracic aorta, allowing blood to enter fetal circulation w/out going through the lungs
-this structure closes at birth
Pectus Excavatum
-the most common congenital deformity of the chest
-a funnel-shaped,asymetrical depression due to a posterior displacement of the sternal body
Pectus Carinatum
Results in a prominant sternum
The Mediastinum
Symptomatic lesions are malignant in 60% of all patients
Carcinoma of the Lungs
-leading cause of death due to cancer in the U.S.
-in most cases, it is the result of smoking
-90% off all patients are cigerette smokers
Blunt or penetrating trauma may result in an accumilation of air
Cardiac Tamponade
-compression of the heart due to a collection of blood or fluid w/in tge pericardium
-usually the result of penetrating trauma
Cardiac Tamponade Treatment
-must be immediate
-pericardial aspiration through a small subxiphoid incision is 1st step
-must be ready for median sternotomy or thoracitomy in case pericardiocentesis results in massive blood loss
A sac formed by localized dilation of the walls of artery due to structural weakening
True Aneurysm
The wall of the sac consists of one or more of the layers that make up the wall of the blood vessel
**Atherosclerotic aneurysm
Thoacic Aortic Aneurysm
-chest pain is the cheif complaint
-may be asymptomatic
Spindle Shaped Aneurysm
Involve the entire circumference of the artery
Dissecting Aneurysm
Involve hemorrhage into the arterial wall
-general term designating primary desease of the myocardium
-enlarged heart
-often of obscure
Sinus Tachycardia
-an atrial
Sinus Bradycardia
-an atrial
Acyanotic Defects
-congenital heart defect
-ventricular septal defect
-patent ductus arteriosus
Ventricular Septal Defect
An abnormal opening in the wall between the right
Patent Ductus Arteriosus
A failure of that fetal structure to completely close at birth
Cyanotic Defect
1. Tetrology of Fallot
2. Transposition of the Great Vessel
3. Tricuspid Atresia
4. Truncus Arteriosus
Tetrology of Fallot
Four Defects:
1. Ventricular septal defect
2. Infundibular or Pulmonary valve stenosis
3. An aorta that overides the ventricular septal defect
4. Right ventricle hypertrophy
Severe Tetrology of Fallot
Infants may require a shunt between the aorta
Truncus Arteriosus
Characterized by having a single artery arising from both ventricles
Rigid Bronchoscopy
-typically used to remove foreign objects in children
Anteroposterior (AP)
These radiologic studies of the chest can determine the overall size of the heart
Cardiac Patient Preperation
-for posterolateral positioning
-OR personell should have 4' adhesive tape
-pleur-evac is a closed water-seal drainage system
-STSR should not allow the lens with light cord attached to touch drape as it may ignite the drape
Cannot be insufflated, double lumen endotracheal tubes allow single lung ventelation
Pump Oxygenerator
-"heart-lung machine"
-used in cardiac surgery to remove unoxygenated blood from the venous system, oxygenated
Cannula Placement
-into the right atrium for draining venous blood
Myocardial Protection
During cardiopulmonary bypass is accomplished with systemic hypothermia
Intra-Aortic Balloon Pump
-mechanical device designed for circulatory support AFTER cardiac procedures
Coronary Artery Bypass Grafting
There should never be water left on your back table because it is easily mistaken for saline when filling cannulae
Aortic Valve Replacement
-median sternotomy is performed
-bone wax is used to seal off bleeders from sternal walls
Repeat Cardiac Procedures
Be prepared to cannulate femorally
Permanant Pacemaker Insertion
1. Endocardial leads
2. Epicardial leads
Endocardial Leads
-pacemaker insertion
-generally placed through the subclavian vein into the right ventricle or atrium
Epicardial Leads
-pacemaker insertion
-attached directly to the myocardium during cardiac surgery or through a subxiphoid approach
Procedures for Correcting Tetrology of Fallot
-median sternotomy is performed
-cardiopulmonary bypass (CBP)
-false aneurysm
-pulsitile hematomas that are not contained by the vessel layers but are confined by a fibrous capsule
Thoracic Cavity
Has 3 divisions
Right Lung
Has 3 lobes