module 11 general concepts in altered pulmonary function Flashcards
general concepts in altered pulmonary function
hypoventilation and hyperventilation hypoxemia and hypoxia acute respiratory failure alterations in pulmonary vasculature pulmonary malignancy
obstructive pulmonary disease
inc. airway resistance develops in localized regions d/t
- obstruction of airway from inc. sputum production
- mucosal hypertrophy and edema
- loss of structural integrity
- narrowing of airway from bronchial small muscle contraction
- - during expiration air leaves following path of least resistance -> maldistribution of gas
hypoxemia
deficient levels of blood oxygen
- low PaO2 or Hgb saturation
hypoxia
dec. in tissue oxygenation
- hypoxic hypoxia
- anemic hypoxia
- circulatory hypoxia
- histotoxic hypoxia
hypoxic hypoxia
dec PaO2 despite normal O2 carrying capacity
- high altitude
- hypoventilation
- airway obstruction
- O2 therapy adequate tx
anemic hypoxia
dec. O2 carrying ability r/t low Hgb
circulatory hypoxia
dec. blood flow/CO
- shock
- cardia arrest
- blood loss
- thyrotoxicosis
- CHF
histotoxic hypoxia
toxic substances prevent tissue oxygenation
normal VQ
from pulmonary artery -> alveolocapillary membrane w/ full alveoi, able to have gas exchange -> pulmonary vein
low VQ
pulmonary artery -> alveolocapillary membrane
impaired ventilation -> minimal gas exchange
-> pulmonary vein w/ hypoxemia
shunt (very low) V/Q
pulmonary artery -> alveolocapillary membrane
blocked ventilation-> collapsed alveoli -> no gas exchange
-> pulmonary vein w. hypoxemia (higher)
Blood goes from R - L side of heart with out passing through ventilated area of lungs
High V/Q
impaired perfusion -> alveolar dead space
-> hypoxemia
no blood flow to a ventilated alveoli
anatomical shunts
VSD
ASD
patent ductus arteriosus
intrapulmonary shunts
alveoli perfused but not ventilated
- localized pneumonia
- ARDS
acute respiratory failure defined as
disturbed gas exchange -> abnormal arterial blood gas values
- PaO2 < 60
- PaCO2 > 50
- pH < 7.30
acute respiratory failure 3 contributing factors
- failure of respiration (oxygenation) -> hypoxemia with normal/ low CO2
- failure of ventilation -> hypercapnia
- Combination resp and ventilatory failure
general r/t poorly matched V/Q -> hypoxemia
acute respiratory failure pahtogenesis
can develop from any abnormality in
- airways
- alveoli
- CNS/PNS
- resp. muscles
- hypoperfusion
- chest wall
- diaphragm
- pleural space
acute resp failure and ventialtion
ventilatory demands > ventilatory capacity
acute resp. failure s/s general
hypoxia hypercapnia HA dyspnea confusion dec. LOC restless agitation dizzy tremors initial HTN -> hypoTN and inc. HR
acute resp. failure early s/s
rapid, shallow breathing
inc. inspiratory muscle movement
acute resp. failure late s/s
cyanosis nasal flaring retractions cool, clammy skin dysrhythmia dec. cap refill
pulmonary HTN
sustained increase in pulmonary artery pressure > 25mmHg
constricted vessels in lungs
hypertrophy of RV
primary pulmonary HTN
idiopathic
rare, rapily progressive
women > men
associated with portal HTN, HIV, appetite suppressing drugs
secondary pulmonary HTN
vasoconstrictive obstructive obliterative (loss of capillary bed) inc. left atrial pressure inc. pulmonary blood flow inc. resistance to blood flow
pulmonary HTN s/s
often asymptomatic until significant damage done d/t distensibility of capillaries and ability to recruit more.
- exercise intolerance
- syncope
- inc. dyspnea
- chest pain on exertion
- fatigue
- hemoptysis
- pulmonary edema
pulmonary venous thromboembolism
>90% from veins of lower extremities virchow's triad - venous stasis - hypercoagulability - intimal injury Causes V/Q mismatch (dead space) - alveoli is adequate but no blood flow
thrombotic embolism
blood clots develop in venous system, predominately in thighs and legs
fat embolism
globules of fat secondary to fx of pelvis or long bones
amniotic fluid embolism
collections of fluid, hair, or other debris r/t complicated labor
air embolism
venous access through IV catheters
tumor embolism
fragment from malignant tissue
foreign material embolism
foreign bodies
- bullets
- sutures
- catheter tips
- PO meds injected IV
septic embolism
infected tissue or related substances
parasitic embolism
parasites present in lung vasculature
lobes associated with pulmonary embolism
lower lobes d/t increased blood flow
pulmonary embolism s/s
restless apprehension anxiety dyspnea inc. HR inc RR sudden dyspnea and chest pain medium to massive PE can worsen into HF, shock, or respiratory arrest
pulmonary malignancies
85% r/t tobacco smoke large cell: 10-15% small cell: 15-20% squamous cell: 20-30% adenocarcinoma: 35-40:% - 32% of cancer deaths in men, 25% in women
pulmonary malignancy s/s
vague
asymptomatic till advanced stage
intrathoracic vs extrathoracic
highest risk for pulmonary malignancy
started smoking before 25
one or more packs a day for 20 years
work with asbestos
> 50 y/o
intrathoracic malignancy s/s
dyspnea cough chest pain hemoptysis inc. sputum hoarsness phrenic nerve -> paralysis of hemidiaphragm on affected side -> pneumonia, atelectasis
extrathroacic malignancy s/s
wt loss fatigue anorexia anemia clubing facial and upper extremity edema with vena cava compression
