midterm review

Diffusion

  • Definition: Diffusion refers to the transfer of oxygen from the alveoli in the lungs to the bloodstream.

Ventilation

  • Definition: The breathing process involving:

    • Contraction of the diaphragm

    • Use of accessory muscles

    • Expansion of the ribs to pull air into the lungs.

Perfusion

  • Definition: The movement and absorption of oxygen molecules into body tissues, also referred to as oxygenation.

Conditions Affecting the Pleural Cavity

  • Pneumothorax: Presence of air in the pleural cavity that can collapse the lung and displace mediastinal structures.

  • Hemothorax: Presence of blood in the pleural cavity that can also lead to lung collapse.

  • Exudate: Fluid in the pleural space that prevents lung expansion and can lead to full collapse.

Respiratory Conditions

  • Apnea: Cessation of respiration.

  • Dyspnea: Difficulty or painful respiration.

  • Hyperventilation: Abnormally fast rate of respiration.

  • Hyperpnea: Excessively deep respiration.

  • Cyanosis: Blush tint to skin due to poor oxygenation.

Pulmonary Function Tests (PFTs)

  • Purpose: Measure lung function and volume.

  • Tidal Volume: Volume of air exhaled during normal respiration.

  • Minute Volume: Amount of air exhaled per minute.

  • Vital Capacity: Total volume of air exhaled after maximum inspiration.

  • Total Lung Capacity: Total amount of air in the lungs when fully inflated.

  • Peak Expiratory Flow Rate (PEFR): Maximum rate of air expelled in forced expiration.

Blood Gas Analysis

  • ABG’s (Arterial Blood Gases): Analyze levels of oxygen and carbon dioxide in the blood, along with pH levels.

Imaging Techniques

  • X-ray: Used to view the chambers and structures of the heart and lungs.

  • CT Scans: Advanced imaging techniques used in pulmonology, often for detecting pulmonary embolism.

  • Pulmonography: Assessing pulmonary function.

Bronchoscopy Procedures

  • Flexible Bronchoscopy: A slender, tube-like optic instrument used with local anesthetic for viewing peripheral bronchi and performing biopsies while the patient remains conscious.

  • Rigid Bronchoscopy: A large, metal tube used with general anesthesia for foreign body removal and larger biopsies.

Advanced Bronchoscopy Techniques

  • Electromagnetic Navigation: Aligns with CT scans to guide bronchoscopy.

  • EBUS (Endobronchial Ultrasound): Used for lymph node identification and biopsy during bronchoscopy.

Chest Drainage Systems

  • Purpose: Allow lungs to expand by re-establishing negative pressure in the pleural cavity, removing air, blood, or fluid.

  • Pleur-vac: Operates on the water seal principle to prevent air from re-entering the chest.

  • Chest Tubes: Inserted through a small incision and sutured to the chest wall.

Surgical Procedures

  • Thoracotomy: Open surgery with a posterolateral incision — access to lung structures.

  • Retractor for shoulder — scapular retractor

  • Preventing severe hemorrhage the edges of the wound are covered with laborontomy sponges to protect from bleeding

  • Lung Volume Reduction Surgery (LVRS): Removal of diseased tissue to enhance function of remaining healthy tissue due to loss of elasticity often from smoking. Pathology: Associated with chronic obstructive pulmonary disease (COPD) and pulmonary emphysema.

  • Lobectomy: Surgical removal of a lobe of the lung, often performed via video-assisted thoracoscopic surgery (VATS).

  • Pneumonectomy: Removal of an entire lung often due to extensive tumors or abscesses. — nerves are carefully preserved during pneumonectomy

  • Lung Transplantation: Involves removing a diseased lung and replacing it with a donor lung, while preserving donor nerves. ( Removal lobe only )

  • Decortication: Surgical removal of fibrous tissue overlying the lung (pleurectomy retrieves parietal pleura).

  • Right lung - 3 lobes

  • Left lung - 2 lobes

  • Hemoptysis - coughing up blood

Cardiac Anatomy and Physiology

  • Conduction System of the Heart: Includes the

  • SA Node (sinoatrial node), which acts as the heart’s pacemaker, and spreads impulses through the AV Node (atrioventricular node) and down the Bundle of His to Purkinje fibers in the ventricles.

  • Cardiac Catheterization: An interventional radiology procedure used to visualize heart chambers and large vessels to assess functionality and pressure.

  • Right Heart Catheterization (RHC): Assesses pressures in the right atrium, ventricle, and pulmonary artery.

  • Left Heart Catheterization (LHC): Evaluates systemic resistance and valve function via arterial puncture in the femoral or brachial artery.

  • Angiography: Process of imaging using a contrast medium injected into an artery.

  • Sa node known as the hearts pacemaker initiates the cardiac cycle

  • AV. Node located in the intra atrial spectrum receives impulses from the SA node

  • Bundle of his conducts impulses from the AV. Junction to the ventricular walls

  • Punkinje fibers the final pathway in the conduction system that causes the ventricles to contract

  • Intravascular ultrasound uses a catheter tipped with a transducer to measure blood flow rate inside a vessel

Cardiopulmonary Bypass (CPB)

  • System: Temporarily replaces the function of the heart and lungs during surgery using a pump and oxygenator.

  • Components:

    • Aortic Cannula: Delivers oxygenated blood from the pump.

    • Venous Cannula: Drains blood back to the pump from the heart.

    • Transitional Cannula: Used for delivering cardioplegia directly into the coronary sinus.

Cardiac Conditions

  • Atrial Flutter: Heart rate ranges from 240 to 350 beats per minute.

  • Cardioplegia: Method of intentionally stopping the heart's pumping action, typically using a potassium chloride solution.

  • Symptoms of Heart Dysfunction: Ventricular Fibrillation leading to ineffective contractions; Ischemia due to localized inadequate blood supply.

  • LV Vent Decompresss the left ventricle and removes air

  • Ejection Fraction Measurement: Assessing the amount of blood pumped from the ventricle.

  • Antegrade- infuse into the aorta

  • Retrograde - solution infused into the coronary venous system via the coronary sinus

  • VL surgical procedures - stenosis constriction or regulation (leaking of the valve) between the left atrium and the left ventricle— median sternotomy - partial or full midline incision

Heart Valve Issues

  • Stenosis: Constriction of the valve.

  • Ventricular fibrillation- chaotic disorganized stimulation of one or both ventricles that does not pump the blood

  • Ventricular angiography- demonstrates the movement of blood through the valves and can be used to measure the ejection fraction and end systolic and diasystolic volumes

  • Regurgitation: Leaking of the valve, causing undirectional blood flow difficulties.

  • Aortic Valve Replacement: Replacement occurs when the valve fails to function due to disease or damage.

  • Layers of the heart— epicardium . Myocardium , inner endocardium

  • Disease or interference in the conduction system results in uncoordinated electrical activity in the cardiac muscle and may cause ineffective contractions

  • Atrial fibrillation chaotic disorganized stimulation of one or both that prevents atrial contraction

  • Heart transplantation may be performed in suitable patients with end-stage cardiac disease

Major structures

  • Arteries

  • Veins

  • Capillaries

Tunica Externa - adventia protect vessels from injury and provides structural strength

Tunica media composed of inner layers of smooth muscle bonded by connective tissue

Tunica intima secrete substance that causes vasodilation or constriction and those that prevent platelet aggravation in the vessels

Blood not pumped through the veins rather milked toward the heart by contractions in skeletal muscle in the peripheral system

Arteries

  • Thick walls

  • Elastic

  • Blood moves through the arteries by pumping action of the heart

  • No internal valves

  • Loss function can lead to tissue, injury or death

  • oxygenated blood

Veins

  • Thin walls

  • Deoxygenated blood

  • Less elastic than arteries

  • Blood moves through veins by the contraction of skeletal muscles

  • Internal valves prevent black flow

  • Bleed slowly when severed

  • Closer to the skin

Andiography- is the injection of contrast media into a selected artery and it branches to determine the exact location of stricture occusion or malfunction

Endovascular aneurysm repair- expanding stent deployed from the femoral artery either by percutaneous or open technique ( Main body of the stent is separated from the craft limbs which form the bifurcated y)

Arterial venous shunt or arterial venous fistula- is to treat vascular access

Fusiform aneurysm most common bulges outward symmetrically

Saccular aneurysm- protrudes from one way only

Pseudo — ruptures in vessel Wall wear blood is contained by surrounding tissue rather than vessel loops

Fem-Fem bypass - performed for blockage in iliac artery

fem-pop bypass - blockage of femoral artery - restores bloodflow

Brain Structure and Functionality

  • Cerebrum: Largest part, controlling motor activities and sensory impulses; responsible for thought and behavior.

  • Lobes of the Brain:

    • Frontal: Forehead and orbits, implicated in reasoning.

    • Occipital: Back of the skull, controls vision.

    • Temporal: Both sides of the cranium, regulates memory, sensation, language, and emotions.

    • Parietal: Sides and roof of the cranium, related to language control.

Brainstem and Circulatory Systems

  • Components: (brainstem) Includes the pons and medulla oblongata, vital for cardiac and respiratory functions.

  • Circle of Willis: A circular network of arteries providing redundant blood flow to the brain; crucial since the brain requires a significant amount of oxygen.

  • Cerebrospinal Fluid (CSF): cushions and nourishes and cleans the brain, with conditions like hydrocephalus leading to excessive CSF, often treated with shunts.

  • Hydrocephalus - excessive CSF treated with shunts to drain fluid to the abdominal or heart

Hematomas

  • Epidural - between skull and dura due to trauma

  • Subdural- between dura and brain

Brain Divided

  • Cerebrum - forehead

  • Cerebellum- hindbrain

  • Brain stem

Procedures

  • Craniotomy - opening the skull to access tumors or aneurysms

  • Craniectomy - Bone flap is removed, stored in antibiotic solution

  • Laminectomy- removing lamina to relieve pressure

  • Rhizotomy - cut nerves root for pain spasms

  • Cordotomy- cut nerves fibers in the spinal cord for terminal pain

  1. Brain

  2. Pia mater

  3. The anachnoid

  4. The dura mater

  5. Carnium

  6. Pericranium

  7. Muscle

  8. Galea

  9. Connected tissue

  10. Scalp

  11. Hair

Pericranium posterior layer of the skull

Midbrain

  • Hypothalamus

  • Thalamus

  • Pituitary gland

Cervical -7

Lumbar - 5

Sacral -5

Thoracic - 12

Nerve and Spinal Procedures

  • Spina Bifida: Incomplete closure of vertebral arches, with the most severe form being myelomeningocele.

  • Surgical Access: Various procedures for accessing the brain include craniotomy and craniectomy.

  • Nerve Interventions: Procedures can involve cutting nerve roots or fibers to relieve pain or spasms, termed Rhizotomy and Cordotomy.

Cranial Nerves

  • Key Functions:

    • Olfactory: Sense of smell.

    • Optic: Visual activity.

    • Oculomotor: Eye movement control (pupil dilation).

    • Trochlear: Eye movement down and laterally.

    • Trigeminal: Chewing and facial sensation.

    • Abducens: Lateral eye movement.

    • Facial: Facial expressions and sensation.

    • Vestibulochlear : hearing and balance

    • Glossopharyngeal: gagging and swallowing

    • Vagus : stimulates pharyngeal and laryngeal affects the heart pancreas lungs and digestive system

    • Accessory : helps control pharyngeal and laryngeal also controls the cranial and spinal portion

    • Hypoglossal: stimulates muscle of the tongue

Peripheral Nervous System

  • Structure: Composed of small bundles of nerves surrounded by a sheath; includes both the autonomic and somatic nervous

  • ANS involuntary controls, heart rates, respiration control of fight or flight.

  • SNS voluntary action can be controlled

  • Endoneumium - surrounded by sheath

Surgical Techniques and Instruments

  • Lidocaine and Epinephrine: Lidocaine acts quickly for anesthesia but has a short duration, while epinephrine reduces bleeding by constricting blood vessels.

  • Various Scissors Functionality:

    • Metz: Scissors for delicate tissue. Cut vessels , cut subq , small prolene suture

  • Mayo: Used for tougher tissue, cut uterus

  • Straight mayo - cut suture cut bandages cut dreams cut umbilical cord

  • curved mayo - cut tough tissue, cut uterus

  • Potts - extended station into vessel

  • lister scissors - cut inner layer of cast cut bandages cut umbilical cord

  • Straight Iris- cut suture in very small area like finger

  • Curved Iris - cut tendon or muscle in very small area like finger

  • Tenatomy - cut delica tissue and very small area