Oxygen & Perfusion Disorders Flashcards
Acute respiratory failure is defined by what PO2 and PCO2 levels?
PO2 under 60 mmHg, and PCO2 over 50 mmHg
What are hallmark SX of hypercapnia (high levels of CO2)?
Dyspnea and HA
What is the pathophysiology behind “pickwickian” syndrome?
aka obesity hypoventilation syndrome -> pts who are obese may blunt their ventilation drive & increase the mechanical load on the chest (due to weight)
How do you treat obesity-hypoventilation syndrome?
weight loss
imaging finding indicative of ARDS?
Air bronchogram
Chief symptom of hypoxemia?
dyspnea
Signs of hypoxemia?
cyanosis, restlessness, confusion, anxiety, delirium, tachypnea, bradycardia or tachycardia, hypertension, cardiac dysrhythmias, and tremor
Signs of hypercapnia?
peripheral and conjunctival hyperemia, hypertension, tachycardia, tachypnea, impaired consciousness, papilledema, and asterixis (tremor of hand when wrist is extended).
What are risk factors for development of acute respiratory failure?
smoking, drinking, family hx of respiratory disease, lung cancer, COPD
What is the main therapeutic goal in acute hypoxemic respiratory failure?
ensure adequate oxygenation of vital organs.
How do you treat acute respiratory failure via non-ventilatory methods?
With nasal cannula of inspired oxygen. Higher concentrations may be needed with ARDS, pneumonia, parenchymal lung disease patients
How do you treat ARF via ventilatory methods?
via face mask (noninvasive) or
tracheal intubation
What is first line therapy in COPD patients with hypercapnic respiratory failure that have a patent airway?
NPPV (non invasive positive pressure ventilation) via full face mask or nasal mask
What is a common side effect of overinflation?
acute respiratory alkalosis
What is a serious complication of mechanical ventilation?
Ventilator- associated pneumonia
What do you need to take into consideration when feeding a patient in respiratory failure?
Overfeeding, especially with CHO-rich formulas, should be avoided, because it can increase hypercapnia
How does ARDS differ from respiratory failure?
ARDS is acute failure within 1 week of a systemic or pulmonary insult w/o evidence of HF.
Risk factors for ARDS?
sepsis, aspiration of gastric contents, shock, infection, lung contusion, nonthoracic trauma, toxic inhalation, near-drowning, multiple blood transfusions.
What is a common etiology of ARDS?
damage to endothelial cells and alveolar epithelial cells causes increased vascular permeability and decreased activity and production of SURFACTANT –> leads to pulmonary edema, alveolar collapse, and hypoxemia.
T/F. ARDS can precipitate multi organ failure (kidneys, liver, gut, CNS, CV)
TRUE!
How can you prevent ARDS?
you can’t :(
Treatment of the hypoxemia usually requires:
tracheal intubation and positive-pressure ventilation
Which body position may help oxygenation in ARDS patients?
prone
ARDS + sepsis = what mortality rate?
90%
What are the lasting effects on ARDS survivors?
cough, dyspnea, sputum production - tend to improve over time.
Most patients with obesity-hypoventilation syndrome also suffer from:
Obstructive sleep apnea, this must be treated aggressively
How does hyperventilation affect CO2 levels?
DECREASE (hypocapnia)
How is chronic hyperventilation diagnosed?
if symptoms are reproduced during voluntary hyperventilation
How does acute hyperventilation present?
hyperpnea, paresthesias, carpopedal spasm, tetany, and anxiety
How can you treat hyperventilation in the office?
pursed lip breathing, or through the nose with one nostril pinched, or rebreathing expired gas from a paper bag
What value of systolic pulmonary pressure is considered hypertensive?
> 30 mm Hg (normal is 25/15)
Most common cause of pulmonary HTN?
Heart failure (left –> right) (group 2)
What lung conditions can cause pulmonary HTN?
COPD, sleep apnea, thromboembolism, interstitial lung disease, pulmonary fibrosis, bronchiectasis (group 3)
Which demographic is Pulm HTN most commonly seen in?
women around 50 years
What is the most common symptom of Pulm HTN?
PROGRESSIVELY worsening SOB on exertion. Sometimes syncope on exertion
T/F: chest imaging and PFTs are useful in determining the cause of pulm HTN in group 3.
True!
What is the gold standard for diagnosis and quantification of pulm HTN?
right-sided catherization
Patient has unexplained pulm HTN and a hx of PE or risk factors for PE, what should be done?
Need to rule out PE/thromboembolic disease. V/Q lung scanning is sensitive test that differentiate this.
T/F. Patients with group 3 pulm HTN should be receiving supplemental oxygen.
TRUE if hypoxic at rest or with physical activity. If have COPD need to supplement for >15 hrs/day.
Which non-pulmonary drugs are approved by the FDA to treat pulm HTN?
WEINER drugs!! Viagra, cialis ;)
T/F. The presence of cor pulmonale carries a poor survival outcome regardless of the cause of pulm HTN,
TRUE
Cor pulmonale usually responds to measures that reduce pulmonary artery pressure, such as:
supp oxygen, correct acidemia, bed rest, salt restriction, diuretics
Acute pulmonary edema presents characteristically like:
severe dyspnea, production of PINK FROTHY SPUTUM, and diaphoresis and cyanosis. RALES in all lung fields
What are some physical or social aspects that can make a person more prone to sleep apnea?
narrowed upper airways, ingestion of alcohol or sedatives before sleep, common cold, hypothyroidism and cigarette smoking are additional risk factors.
What is the common demographic for patients with obstructive sleep apnea/
obese, middle-aged men
What are the first steps in management of OSA?
weight loss and strict avoidance of alcohol and hypnotic drugs
How do you diagnose OSA?
polysomnography
What labs should be run with suspected OSA patients?
thyroid function tests (TSH, T4, serum) - need to exclude hypothyroidism
