Pulmonary Flashcards
Anatomy of the Pulmonary System
-Primary muscle of ventilation: Diaphragm
-Right Lung: 3 Lobes
-Left Lung: 2 lobes
What is the normal ventilation rate (Liters)
4L per minute
What is anotomic dead space? What is normal?
-Volume of space that does not participate in gas exchange
-Normal is 2mL/kg of tidal volume
Normal Ventilation/Perfusion Ratio
5L perfusion/min (Q)
-Ideal lung unit = 0.8 ratio
What is the Lab Diagnostic that Indicates Ventilation
-PaCO2 is the clinical indicator for ventilation NOT PaO2
What is dead space ventilation? What body parts experience dead space ventilation?
- Areas of the pulmonary system with no gas exchange
-Nose, mouth, trachea, bronchi
-The only place where gas is exchanged is the alveolar sacs
Pulmonary Embolism: Signs and Symptoms + Causes
Massive = >50% Occlusion
Submassive = < 50% Occlusion
-Refractory hypoxemia, tachypnea, dyspnea, chest pain
-Can be caused by blood, air, fat, or amniotic fluid
-Puts strain on the right ventricle as it tries to pump the same amount of blood through a obstructed circulatory system
-Leads to RIGHT ventricular heart failure
Leading cause of Pulmonary Embolism
- 80% to 90% result from DVT
- VTE and Fat Embolism
Treatment of Pulmonary Embolism
-Fluids!
-Coumadin on the first day of treatment
-Heparin drip and injections
-Fibronolytic Therapy
-Inotropes (maintain cardiac output)
Oxyhemoglobin Dissociation Curve
LEFT SHIFT: Causes HgB to “hold on” to more O2
-pH move UP
-BAD for tissues (SaO2 is high but tissues don’t receive O2)
RIGHT SHIFT: Causes HgB to “release” O2 more readily
-pH moves DOWN
-GOOD for tissues (SaO2 is low but tissues receive O2 readily)
Carbon Monoxide Poisoning (CO)
-CO attaches to HgB and does not allow the RBC to carry O2 or CO2
-CO has a higher affinity for Hgb than O2 and CO2
-Treatment: 100% oxygenation (Hyperbaric) until Carboxyhemoglobin level is <10%
-Finger probe cannot differentiate between CO and O2 so do not rely on finger probe SATs
Acid Base - How does hydrogen effect pH
-There is an inverse relationship between H+ and pH
- The more H+ the lower the pH (acidic)
-The less H+ the higher the pH (alkolotic)
Methods of pH correction. Metabolic and Respiratory
-Respiratory System (Lungs) corrects pH rapidly (within minutes to hours)
-Metabolic system (kidneys) corrects pH slowly (within hours to DAYS)
Anion Gap. What is it? What is normal? What makes an anion gap worse?
-A measurement of acid base balance in the blood typically used to identify cases of metabolic acidosis
-Normal range is 5-15
-Worsening factors: DKA, Salicylate intoxication, alcohol ketosis, lactic acidosis
Lung Compliance. Static and Dynamic
-How well the lungs accept the positive pressure ventilation from CPAP/BiPAP/Ventilator. Are the lungs elastic or stiff
-Static: Measures the elasticity of the tissues of the LUNG (Pneumonia, ARDS)
-Dynamic: Measures the elasticity of the tissues in the AIRWAY (Asthma)
-Increase in plateau pressure OR increase in peak inspiratory pressure will DECREASE lung compliance
-Static Problems (lung) have a decrease in BOTH static and dynamic compliance
-Dynamic problems (airway) have a decrease of ONLY the dynamic compliance and the static compliance remains NORMAL
How does lung compliance effect a patients?
-Decreased lung compliance will increase the patients work of breathing
Treatment for Respiratory Failure
-Position patient upright, bronchodilators, suction, ventilate, avoid O2 toxicity
-Correct hypotension and cardiac arrhythmias
CPAP
Continuous Positive Airway Pressure
-FiO2 + 1 pressure setting (PEEP)
BiPAP
Bilevel Positive Airway Pressure
-FiO2 + 2 pressure settings (IPAP and EPAP)
-Useful for hypoxemic or hypercarbic respiratory failure- expected to make a fast recovery
Invasive Mechanical Ventilation
-Placement of an endotracheal tube
-X-ray confirmation ETT is 3-5cm above the carina
-Poor positioning typically occurs in to the right lung 2/2 short mainstem bronchus and low angle of right lung
Mechanical Ventilation - Set Volume OR Set Pressure
-A ventilator can provide a Set breath volume OR a set breath pressure NOT BOTH
Assist Control Mode (AC)
-Always delivers a set tidal volume at a set respiratory rate
-The volume will also be provided for spontaneous breaths
-Risk for barotrauma if patient is hyperventilating spontaneously and peak pressures increase
Pressure Control Mode (PC/AC)
-Always delivers a set pressure at a set respiratory rate
-Referred to as “pressure above PEEP”
-Set pressure will be provided for spontaneous breaths as well
-No guaranteed tidal volume
Synchronized Intermittent Mandatory Ventilation (SIMV)
-Always delivers a set tidal volume at a set respiratory rate
-Spontaneous breaths are delivered when the airway pressure drops below the end-expiratory pressure
-Good setting to ween off the ventilator
Pressure Support Ventilation (PSV)
-The patient triggers every breath but the ventilator provides increased airway pressure (if needed) to reach an adequate tidal volume
Tidal Volume Normal Ranges
-Based off of IDEAL BODY WEIGHT NOT CURRENT BODY WEIGHT
-General: 6-10mL/kg
-ARDS patients: 4-6mL/kg
Obstructive Lung Diseases; COPD, Asthma, Bronchitis
-Disorders that trap air and gas within the lungs, making it difficult to get air OUT
-Wheezing
-Barrel chest
Bronchitis
-Inflammatory response to an irritant in the lungs or airway
-Always considered an acute illness unless the patient has had bronchitis for greater than 3 months a year for the past 2 years or more
COPD
-Starts as an inflammatory response to an irritant in the lungs or airway
-Smoking is the #1 cause
-May also be caused by Alpha-1 antitrypsin disease (genetic)
-Leads to air obstruction and air trapping from collapsed alveoli, decrease in surface area leading to less gas exchange
-A chronic COPD patient may have a High HCO3 due to complete compensation
-May lead to cor pulmonale (right ventricular enlargement) and elevated CVP
COPD Treatment
-Treat cause of admission (what caused this exacerbation?)
-O2 administration - be careful because the more O2 given = the more CO2 retained
-Bronchodilator (SABA; Short acting beta agonist; albuterol)
-Clear secretions
-Hydration and humidified O2
-High calorie, low carbohydrate foods
Status Asthmatics
-A hyper-reactive airway that causes sever narrowing
-Not relieved with meds
-Severe air trapping with no air movement at all
-Increase in intrathoracic pressures which decreases venous return to the heart and increases RV afterload
Status Asthmatics Presentation/Treatment
-Cough, tachycardia, tachypnea, anxiety, (late) low LOC
-Flattened diaphragm on x-ray
-Pulsus Paradoxus > 15mmHg (severe is >18)
-On the Vent: Use low tidal volumes and increase expiration time to reduce the amount of air trapping
-Meds: Bronchodilators, anticholinergics, corticosteroids, hydration
-Avoid sedation
Restrictive Lung Diseases; Acute Lung Injury; ARDS; Pneumonia, Pulmonary Fibrosis
-These diseases restrict the lungs from expanding during inhalation
-Lung compliance and lung volumes are decreased
Acute Lung Injury
-The first step of the progress of ARDS
-Direct or indirect injury which causes a significant amount of inflammatory response leading to increased permeability causing edema -> ARDS
Restrictive Lung Disease: What is ARDs: Acute Respiratory Distress Syndrome
-A condition 2/2 illness or injury that allows fluid to leak in to the lungs (opacities bilaterally on x-ray)
-Breathing becomes difficult and oxygen cannot get IN to the body
-Classified as Mild, Moderate, or Severe
How to determine ARDs Severity (Mild, moderate, severe)
-PF Ratio! (PaO2/FiO2)
-FiO2 as a decimal (ie 45% = 0.45)
-Mild -The ratio is between 200 and 300 with PEEP or CPAP
-Moderate -The ratio is between 100-200 with PEEP >5
-Severe -The ratio is < 100 with PEEP >5
ARDs Treatment
-Treat admission cause (exacerbation)
-Mechanical Ventialtion
-Infection Prevention
-Upright Patient Positioning or PRONE
No steroids for ARDS patients
3 Stages of ARDS (based on timing not severity)
Exudative: 0-4 days
Proliferative: 3-10 days
Fibrotic: 7-14 days
ARDs Diagnosis Requirements
-chest X-ray showing bilateral opacities
-Must be within 1 week of new or worsening symptoms
-Respiratory failure proven to not be 2/2 cardiac function or fluid overload
Restrictive Lung Disease: Pulmonary Fibrosis
-An interstitial lung disease that causes scarring of the lungs. This reduces elasticity and decreases expansion of the lung. Reduction of gas exchange due to scar tissue
Primary VS. Secondary Pulmonary Fibrosis
-Primary: Inherited or idiopathic
-Secondary: Radiation, medications, medical conditions
Pulmonary Fibrosis Treatments
-Medications (bronchodilators, O2, anti-anxiety agents), oxygen, rehabilitation, supportive care
Restrictive Lung Disease: Pneumonia
-Caused by an infection that leads to alveolar consolidation within the lungs
-Causes fluid and pus to fill alveolar sacs
-May be hard to distinguish between pneumonia and bronchitis; chest x-ray confirms 1 vs. the other
-Bronchitis affects the upper airways while pneumonia affects the lower lungs
Pneumonia Causes
-Pneumonia is most commonly caused by a bacterial, viral, or fungal infection
-May also be from aspiration or parasites
Pneumonia Signs and Symptoms
-Dehydration, tachycardia, chest pain, fever, chills, malaise, productive cough, (elderly) confusion
Pneumonia Treatment
-Chest X-Ray, sputum cultures, ABG
-Antibiotics, antivirals, antifungals (depending on sputum culture result)
-Antibiotic administration should begin within 4 hours of entering the hospital
-GOOD LUNG DOWN
-Early Mobilization
-Suctioning + subglotic suction prior to cuff deflation
-Routine oropharyngeal suctioning
-Give fluids; hydration
-Fever control
-Nutrition
-Oral hygiene
-HOB 30 degrees or higher
Type of Pneumonia: Community, Hospital, Ventilator
-Community Acquired develops outside of the hospital
-Hospital Acquired develops 48 hours after admission
-Ventilator Acquired develops in a patient who has been on a vent. for 2 continuous days OR develops pneumonia 1 day after extubation
Chest Trauma
-Identify the mechanism of injury and the location of the injury
-Chest/Chest Wall: Pulmonary contusion, pneumothorax, hemothorax, lacerations
-Chest: Cardiac rupture, cardiac tamponade, aortic dissection, hemorrhage
Air Leak Syndrome: Pneumothorax
-Caused by a tear in the pleura of the lung. Can be caused by thoracic trauma, barotrauma, or iatrogenic (caused by medical intervention)
Pneumothorax
-Begins as air leaking in to the lungs leading to an eventual lung collapse due to POSITIVE pressure gradient
-Healthy human has a negative pressure gradient allowing the lung to expand with the thorax on inhalation
Pneumothorax Classifications; Simple, TENSION, Hemothorax, Pneumomediastinum
-Tension Pneumothorax Air is unable to exit; causing a mediastinal shift
-Tracheal deviation AWAY from the affected side
-Distended neck veins (JVD)
-Hypotension
Life threatening
Pneumothorax Treatment
-Needle decompression and chest tube placement
-Chest tube insertion site for pneumothorax; HIGH
-Chest tube insetion site for hemothorax; LOW (think fluid would be at the bottom of the lung
Chest Tube Specifications
-If an air embolism is suspected during insertion, place the patient in reverse Trendelenburg and on left side to trap air in the right ventricle
** < 200mL of output in a day; consider weaning **
** > 200mL of output for 2 or more consecutive hours may require intervention!!! **
-No dependent loops in chest tubing
-No milking or stripping the chest tube
-Keep collection chamber lower than the chest
-Suction control chamber determines the amount of suction NOT the wall suction source
-Clamp ONLY when changing the system or when you receive an order (camping cuts off negative pressure and the expanded lung may re-collapse
-Bubbling in the water seal is not normal (if it is continuous)
-Bubbling intermittently (tidaling) on inspiration is normal
Shunt What is it? What should we do?!?
-A shunt is movement from the right side of the heart to the left without being oxygenated in the process (venous blood moves to the arterial side) (result is refractory hypoxemia)
-This causes an extreme V/Q mismatch
-Providing O2 will not correct the hypoxemia present
-Treatment - Administer oxygen AND PEEP
-PEEP keeps expiratory pressure POSITIVE
-Decreases surface tension of the alveoli, increases alveolar recruitment, increases time of gas exchange which allows you to decrease FiO2
Signs of hypoxemic respiratory failure
-Tachypnea, accessory muscle use, abnormal breath sounds
-Tachyarrhythmias (early)
-Bradyarrhythmias (late)
-Cyanosis (Central; lips, earlobes)
-Anxiety and agitation
Hypercapnic respiratory failure
-Shallow breathing
-Bradypnea
-Normal OR abnormal breath sounds
-Progressive loss of consciousness
Pulmonary Hypertension Definition
-Mean Pulmonary artery pressure > 25 at rest and and PAOP that is less than 16 at rest
-Normal Pulmonary artery pressure is
~ 20
- Eventually leads to Right ventricular
Treatment of Pulmonary Hypertension
-Diuretics, oxygen, anticoagulants, digoxin, exercise trainign
Aspiration
-Oropharyngeal is most common
-Usually in right lung due to mainstem bronchus anatomy
-Can lead to ARDS, tachycardia, hypoxemia, hypotension due to fluid shifts
