Study Notes - Pulmonology and Hematology Overview

PULMONOLOGY VOLUME 3 CHAPTER 1

  • Hematopoietic System consists of:

    • Blood (both cells and plasma)

    • Bone marrow

    • Liver

    • Spleen

    • Kidneys

    • Kidneys (and to a lesser extent the liver) produce erythropoietin, a hormone responsible for red blood cell production.

    • The liver removes toxins from the blood and produces many clotting factors and proteins in plasma.

REVIEW OF RESPIRATORY PHYSIOLOGY

  • Inspiration is always an active process, requiring energy and is dependent on:

    • Intact chest wall

    • Intact pleural cavity

  • Expiration:

    • Generally a passive process; occurs as the chest wall and diaphragm recoil to their normal resting state.

    • Expiration does not normally require energy.

Factors Affecting Airflow (Ventilation)

  • Amount of airflow into lungs is dependent on:

    • Difference between pressure in the atmosphere and that inside the chest cavity.

    • Airway resistance

    • Lung compliance

Variance in Lung Volume

  • Volume of air entering lungs variably changes based on metabolic needs of the patient.

    • Influenced by factors such as:

    • Age

    • Sex

    • Physical conditioning

    • Medical illnesses

    • Tidal volume:

    • During quiet respiration, 500 mL of air moves in and out of the lungs of a 70-kg adult.

    • Residual volume:

    • Air that remains in lungs at all times; serves to maintain the patency of alveoli.

    • Peak flow:

    • Measures the maximum rate of airflow during forced expiration.

    • Anatomical dead space:

    • Air rests in trachea, mainstem bronchi, and bronchioles; not available for gas exchange.

Ventilatory Control

  • The medulla oblongata regulates ventilation and contains both inspiratory and expiratory centers.

    • Medullary signals are transmitted through the phrenic and intercostal nerves to the diaphragm and intercostal muscles.

    • Stretch receptors provide input to the medulla’s respiratory center.

    • The most important determinant of ventilatory work is arterial PCO2.

Blood Chemistry Changes

  • Increase in arterial PCO2 results in a decrease in blood pH.

  • Chemical receptors in medulla detect decreased pH, prompting signals to increase the rate and depth of respirations.

Diffusion in the Respiratory System

  • Diffusion is the process responsible for gas exchange; gases move between alveoli and pulmonary capillaries.

    • Respiratory membranes and endothelial lining of capillaries must remain intact for exchange of oxygen and carbon dioxide.

Lung Perfusion

  • Refers to the circulation of blood through the lungs or pulmonary capillaries, dependent on three key conditions:

    • Adequate blood volume

    • Intact pulmonary capillaries

    • Efficient pumping of blood by the heart

Oxygen Transport

  • Oxygen is transported in the bloodstream either:

    • Bound to hemoglobin

    • Dissolved in plasma

  • Oxyhemoglobin:

    • Hemoglobin with oxygen bound.

  • Deoxyhemoglobin:

    • Hemoglobin without oxygen.

  • Oxygen Dissociation Curve:

    • Fully oxygen-bound hemoglobin releases oxygen.

    • Changes in body temperature, blood pH, and PCO2 can alter this curve.

Carbon Dioxide Transport

  • Carbon dioxide transported from cells to lungs occurs as follows:

    • As bicarbonate ion (70%)

    • Bound to globin portion of the hemoglobin molecule (23%)

    • Dissolved in plasma (7%)

Respiratory Locations

  • Respiration occurs in two locations:

    • Pulmonary respiration: In the lungs

    • Cellular respiration: In capillaries

  • Disease processes that impair the pulmonary system will also result in derangements in:

    • Ventilation

    • Diffusion

    • Perfusion

Disruptions in Ventilation, Diffusion, and Perfusion
Disruption in Ventilation can arise due to:

  • Airway obstruction

  • Compromise of thoracic cavity integrity

  • Compromise of lung tissue integrity

  • Disruption in medullary signals

Disruption in Diffusion may occur due to:

  • Changes in the concentration of oxygen in alveoli

  • Alterations to structure or patency of alveoli

  • Alterations to the thickness of the respiratory membrane

  • Fluid and/or infectious material accumulation in alveoli

  • Changes in permeability of pulmonary capillaries

Disruption in Perfusion can be caused by:

  • Reduction in circulating blood volume

  • Reduction in normal circulating hemoglobin

ASSESSMENT

Scene Size-Up

  • Assess for multiple patients with the same complaint.

  • Evaluate for low oxygen concentration environments (e.g., enclosed spaces like grain silos or lower ground areas).

  • Consider possible airborne chemicals or gases (e.g., Haz-mat issues, fires).

  • Account for exposures to contagions, allergens, or extreme weather conditions.

Across the Room Assessment

  • Determine if the patient is “sick” or “real sick”:

    • Appearance

    • Level of consciousness (LOC) – use AVPU; anything less than A/O x 4 raises concern.

    • Is the patient anxious or panicking?

    • Is the patient able to speak in full sentences?

    • Are they complaining of shortness of breath (SOB) or dyspnea?

Indicators of Respiratory Distress

  • Work of Breathing:

    • Positioning

    • Audible respiratory sounds

    • Observe for tachypnea or bradypnea

  • Skin Condition:

    • Look for pallor, diaphoresis, cyanosis (a late finding), or obvious dependent edema (pedal or posterior).

Immediate Interventions for Really Sick Patients

  • If pulseless, initiate arrest resuscitation efforts.

  • Otherwise, assess and correct airway problems, ventilatory issues, and circulatory problems.

Airway Management

  • Start with proper body and head positioning.

  • Clear foreign bodies using Heimlich maneuver, finger sweeps, suction, and Magill forceps if necessary.

  • If unable to completely clear the airway, attempt to ventilate the apneic patient regardless.

  • Use nasopharyngeal airway (NPA) if a gag reflex is present; use oropharyngeal airway (OPA) if there is none.

  • Do NOT forego basic airway maneuvers for advanced airway techniques until absolutely necessary.

Breathing Assessment

  • Extreme tachypnea or bradypnea should be assisted:

    • Tachypnea: Synchronize at 12-20 breaths/minute.

    • Bradypnea: Overdrive at 12-20 breaths/minute.

  • Complaints of dyspnea or SOB should receive supplemental oxygen.

Circulation Assessment

  • Remember the link to cellular respiration.

  • Assess for hypotension (e.g., absence of radial pulse).

  • Evaluate for and treat any life-threatening cardiac dysrhythmias.

Secondary Assessment

  • Obtain a SAMPLE history:

  • Cardiac/respiratory history, medication usage, presence of possible allergic reactions, and associated symptoms (OPQRST).

Physical Exam and History

  • The physical exam should occur in conjunction with medical history, emphasizing whatever is critical for the patient during assessment.

ASSESSMENT OF RESPIRATORY PATIENT

PHYSICAL EXAM

  • Signs of distress can be indicated by pursed lips during exhalation.

  • Examine the nose, mouth, and throat for swelling or signs of infection.

  • An increase in sputum production may indicate an infection of the lungs or bronchial passages.

  • Examine jugular veins for distention.

Lung Exam Procedures

  • Follow standard steps of inspection, palpation, percussion, and auscultation for the chest exam.

    • Abnormal Breath Sounds:

    • Snoring

    • Stridor

    • Wheezing

    • Rhonchi

    • Crackles (rales)

    • Pleural friction rub

Vital Signs

  • The inter-relationship between cardiac and respiratory systems underscores the importance of accurately establishing a baseline for:

    • Pulse Rate and Rhythm: - 4 and 12 lead ECG: - Blood pressure:

    • Respiratory Rate, Rhythm, and Effort: - Pulse oximetry: - Capnography:

MANAGEMENT OF RESPIRATORY PATIENT

  • After supporting the ABCs (Airway, Breathing, Circulation), specific treatments must focus on:

    • Differentiating the cause of the chief complaint

    • Supporting both types of respiration

    • Maximizing oxygen availability within a therapeutic range

SPECIFIC RESPIRATORY DISEASES

Upper Airway Obstruction

  • Causes:

    • Relaxed tongue

    • Foreign bodies

    • Edema or hematoma from facial or neck trauma

    • Upper airway burns

    • Allergic reactions

  • Severe signs:

    • Silent cough

    • Cyanosis

    • Inability to speak or breathe

Signs/Symptoms of Upper Airway Obstruction

  • Edema, trauma, or burns to face, tongue, or neck

  • Conscious Patient:

    • Silent cough

    • Cyanosis

    • Inability to breathe effectively or speak

  • Unconscious Patient:

    • Snoring respirations

    • Inability to ventilate if apneic

Specific Management for Upper Airway Obstruction

  • Dependent on the source of obstruction

  • Basic airway maneuvers and adjuncts used for tongue occlusion

  • Use of FBAO maneuver and/or direct removal techniques with Magill forceps for foreign bodies

  • Treat edema from allergic reactions aggressively with medications

  • Consider performing cricothyrotomy when necessary

Adult Respiratory Distress Syndrome (ARDS)

  • Characterized by fluid accumulation in interstitial lung space.

    • Increases the distance for gas exchange between alveoli and capillaries.

    • Commonly results from sepsis, pneumonia, COVID-19, toxic inhalation, or acute pancreatitis.

  • Signs/Symptoms of ARDS:

    • Gradual decline in respiratory function

    • Dyspnea with noncardiogenic pulmonary edema

Specific Management of ARDS

  • Support pulmonary function through CPAP or intubation

  • Aggressive treatment of the underlying condition is vital

Obstructive Lung Diseases

  • Includes:

    • Emphysema

    • Chronic bronchitis

    • Asthma

    • Typically, smokers have both emphysema and chronic bronchitis.

  • Progressive Development:

    • Patient’s body can adapt to changes until emergent status due to an exacerbation triggers instability.

Emphysema

  • Loss of elastin leading to:

    • Over-inflation of alveoli

    • Loss of alveolar septum

    • Formation of blebs and bullae

    • Reduced lung function and inability to completely expel air

Chronic Bronchitis

  • Characterized by:

    • Decrease in epithelial cells (cilia), hindering debris clearance

    • Increased goblet (mucus-secreting) cells leading to excessive sputum production

    • Narrowing of the bronchioles occurs

Obstructive Lung Diseases - General Signs/Symptoms

  • Chronic dyspnea that worsens with exertion

  • Current or past smoking history or chemical exposures

  • Recurrent respiratory infections

  • Use of inhalers or supplemental oxygen noted

  • Diminished lung sounds noted throughout all fields

Circulatory Impact of Obstructive Lung Diseases

  • Obstructed pulmonary circulation can lead to pulmonary hypertension and subsequently right heart hypertrophy.

    • This condition may lead to chronic cor pulmonale and right heart failure over time.

Emphysema - Specific Signs/Symptoms

  • Weight loss is common

  • Barrel chest appearance

  • Patients may exhibit a pink color from polycythemia

  • Finger clubbing may also be present

Chronic Bronchitis - Specific Signs/Symptoms

  • Productive cough present

  • Patients may be overweight

  • Cyanosis may also be observed

  • Presence of rhonchi on auscultation

Management of Obstructive Lung Diseases

  • Administer supplemental oxygen to maintain oxygen saturation between 90% and 95%

  • Continuous monitoring of level of consciousness

  • Administer nebulized beta agonists and possibly fluid for dehydration

  • Consider using CPAP at lower PEEP settings

Asthma

  • Defined as a chronic inflammatory disorder of airways, often induced by various triggers such as allergens, cold air, exercise, food, or stress.

  • Initial Reaction:

    • Release of chemical mediators like histamine resulting in bronchoconstriction, bronchial edema.

  • Second Phase (6-8 hours post-exposure):

    • Eosinophils, basophils, and neutrophils infiltrate, causing further bronchoconstriction and bronchial edema.

Signs/Symptoms of Asthma

  • History of asthma

  • Prior intubations or medications (MDIs, nebulizer, corticosteroids).

  • Sudden onset following exposure to triggers:

    • Dyspnea

    • Wheezing

    • Diminished lung sounds

    • Waveform capnography may show “Shark's fin” with elevated CO2 levels.

Specific Management of Asthma

  • Administer nebulized beta agonists and corticosteroids

  • Consider using epinephrine and magnesium sulfate

  • Monitor for dehydration and provide IV fluids if necessary

  • Use CPAP with an in-line nebulizer if CDI is warranted

Acute Severe Asthma (Status Asthmaticus)

  • Characterized by no response to repeated doses of beta-agonists with worsening hypoxia and distress.

    • Implement CPAP with in-line nebulizer and administer corticosteroids and magnesium sulfate.

    • Chemical-assisted intubation may be required as a last resort.

Pneumonia

  • A collection of related respiratory diseases initiated by the invasion of infectious agents into the lungs (e.g., bacterial, viral, fungal, aspiration).

  • Classification by Location:

    • Bronchial

    • Lobar

    • Interstitial pneumonia

Pathophysiology of Pneumonia

  • Infection initiates in one lung part, spreading to surrounding alveoli.

  • Accumulation of fluid and inflammatory cells can occur; may result in alveolar collapse and is primarily a disorder of ventilation.

Signs/Symptoms of Pneumonia

  • Recent fever history

  • Deep, productive cough with yellow to brown sputum potentially streaked with blood

  • Pleuritic chest pain can be associated

  • Abnormal lung sounds:

    • Silent regions (due to consolidation)

    • Pleuritic rub

    • Crackles (localized or diffuse)

    • Rhonchi

Treatment for Pneumonia

  • Provide general respiratory support

  • Administer fluids to address dehydration

  • Administer antipyretics (e.g., acetaminophen or ibuprofen) for high fever

  • Early identification of the specific disease is crucial for out-of-hospital treatment

Pulmonary Embolism

  • Definition: An embolus, which may be an air, fat, amniotic fluid, or thromboembolus, lodges in the pulmonary artery.

  • It is a leading cause of acute cor pulmonale.

  • Ventilation occurs in the affected lung segment, leading to a mismatch with perfusion resulting in hypoxic state.

Signs/Symptoms of Pulmonary Embolism

  • Sudden onset of severe, unexplained dyspnea.

  • May have a recent history of immobilization (e.g., hip fracture, surgery).

  • In about 50% of cases, deep vein thrombosis in lower extremity is evident.

Management for Pulmonary Embolism

  • Large embolisms may lead to cardiac arrest; perform CPR if necessary.

  • Administer supplemental oxygen at the highest possible concentration

Spontaneous Pneumothorax

  • Occurs without any blunt or penetrating trauma.

  • Affects a 5:1 male-to-female ratio; more so in tall, thin individuals with a smoking background.

  • Commonly occurs between ages 20 and 40 and has a higher incidence among those with COPD.

Signs/Symptoms of Pneumothorax

  • History of previous spontaneous pneumothorax

  • Sudden dyspnea onset

  • One-sided pleuritic pain

  • Diminished lung sounds on the affected side

Specific Management of Pneumothorax

  • Symptoms and pulse oximetry guides therapy levels.

  • Individuals needing positive pressure ventilation are at risk for tension pneumothorax.

GYNECOLOGY

Pelvic Inflammatory Disease (PID)

  • Inflammation caused by infection in the female reproductive tract, by either bacterium, virus, or fungus.

  • Involves: uterus, fallopian tubes, and ovaries; it is the most common cause of abdominal pain in women of childbearing age and often exacerbated by gonorrhea or chlamydia.

    • Patients may not show symptoms until PID has advanced.

  • Symptoms include walking with a shuffling gait and severe pain, fever, chills, nausea, vomiting; may lead to sepsis.

Ruptured Ovarian Cyst

  • Cysts are fluid-filled pockets in the ovary that can rupture, resulting in abdominal pain.

  • Symptoms include delayed menstrual periods, dyspareunia, and irregular bleeding; associated with vaginal bleeding.

Cystitis

  • Bladder inflammation caused by a urinary tract infection (UTI).

  • Symptoms include urinary frequency, pain or burning on urination (dysuria), and low-grade fever.

Endometritis

  • Infection of the uterine lining; may occur post-miscarriage, childbirth, or gynecologic procedures.

  • Symptoms typically include lower abdominal pain, foul-smelling vaginal discharge, and fever.

Endometriosis

  • Presence of endometrial tissue outside of the uterus.

  • Symptoms include painful menstruation, bleeding, and infertility issues; occurs often in women aged 30-40.

Ectopic Pregnancy

  • Implantation of a fetus outside the uterus, most commonly in a fallopian tube.

  • Symptoms can include unilateral abdominal pain, missed menstruation, and possible vaginal bleeding.

Non-Traumatic Vaginal Bleeding

  • This can result from cramping abdominal pain and the passage of clots and tissue.

  • Situation requires a compassionate approach given its serious emotional impacts.

Trauma - Obstetric Context

  • Blunt trauma is more frequent than penetrating trauma; straddle injuries are a common form of blunt trauma.

  • Vaginal injuries are often lacerations resulting from sexual assault or other traumas.

PRENATAL PERIOD

Overview

  • The period from conception through delivery; fetal development starts immediately after fertilization.

  • Ovulation is when an egg is released from the ovary and, if fertilized, it implants in the uterus; if unfertilized, menstruation results.

Anatomical and Physiological Changes

  • The uterus weight increases from 60g (normal state) to 1,000g during pregnancy, increasing capacity from 10 mL to 5,000 mL.

  • Maternal blood volume increases: 45% during pregnancy.

  • Renal blood flow increases and renal absorption enhances; glucosuria may appear, indicating potential gestational diabetes.

Hormonal Changes

  • A variety of hormonal adjustments occur; mucus plug forms in the cervix to protect the fetus, and cardiovascular changes include increased heart rate and cardiac output.

Major Complications During Pregnancy

  • Hypertensive disorders (e.g., preeclampsia), gestational diabetes, and vaginal bleeding complications (e.g., abortion, placenta previa, abruptio placenta).

Preeclampsia, Eclampsia, and Other Hypertensive Disorders

  • Recognized by elevated blood pressures; mild (hypertension) and severe forms produce a raft of symptoms including generalized edema and proteinuria.

  • Symptoms can precede serious complications like seizures, stroke, or kidney failure if untreated.

Delivery Stages

First Stage

  • Dilation stage, includes organized contractions and progression through cervical dilation.

Second Stage

  • Delivery of fetus; important evaluation factors include timing, frequency of contractions, and maternal urges.

Third Stage

  • Delivery of placenta, requires monitoring of potential complications.

Management Considerations During Birth

  • Assisting the delivery and assuring maternal well-being; understanding and managing potential complications such as breech presentations, prolapsed cords, and ensuring there’s time for proper transport if required.

HEMATOLOGY

Overview of the Hematopoietic System

  • The hematopoietic system includes blood, bone marrow, liver, spleen, and kidneys, with a key role in erythropoietin production and toxin removal.

  • Plasma serves critical functions in transportation, clotting, and buffering the acid-base balance.

Components of Blood

  • Plasma: Contains 90-92% water and 6-7% proteins necessary for transport of nutrients and oxygen; also aids in waste removal.

  • Red Blood Cells (RBC): Last approximately 120 days; affect oxygen release influenced by pH, body temperature, and the Bohr effect.

  • White Blood Cells (WBC): Normally between 5,000-9,000 WBCs/mcL; respond to infection and play a role in immune function. (e.g., HIV impacts T cells).

  • Platelets: Critical to hemostasis; levels too low may lead to bleeding, while high levels can contribute to clotting issues.

Hematologic Emergencies Management

  • Early identification of issues such as anemia, thrombocytopenia, or transfusion reactions is crucial; management strategies vary significantly based on condition severity.

  • Supportive measures for assistance in any hematological emergency should always be in consideration, including oxygen support and assessment for signs of distress.