Non-cardiovascular conditions (CMC) Flashcards
The respiratory system plays a crucial role in maintaining homeostasis by
facilitating gas exchange, delivering oxygen to the bloodstream and expelling carbon dioxide from the body
name the structures of the respiratory system
divided into upper and lower respiratory tracts, including nasal cavity, pharynx, larynx, trachea, bronchi, and lungs
(trachea is start of lower, or the area below the vocal cords so part of the larynx? but basically trachea)
what is an acute PE?
sudden blockage in one of the pulmonary arteries in the lunges, typically caused by blood clots that travel to the lungs from other parts of the body, a condition known as DVT. This blockage can cause significant impairment in pulmonary circulation, leading to respiratory distress and potencial CV compromise.
describe the pathophys of acute PE
involves obstruction of blood flow, which increases PVR. this increased resistance puts strain on the RV of the hart, which has to work harder to pump blood through the obstructed pulmonary circuit. If untreated, this can lead to RV failure and decreased CO, potentially resulting in hemodynamic instability and shock
s/s of PE
variety. sudden SOB, pleuritic chest pain (sharp pain that worsens with breathing), hemoptysis, signs of right heart strain (JVD)
if severe: syncope, sudden CV collapse
dx of PE
CTPA: computed tomography pulmonary angiography to visualize presence of clots in pulm arteries
additionally: D-dimer blood test, which can indicate clot formation
echo: to assess RV function
PE management
focus is on stabilizing patient and preventing further clot formation
AC therapy (heparin, DOAC)
if contraindicated or insufficient, thrombolytic therapy may be used.
if massive or hemodynaic instability: embolectomy or catheter-directed therapies may be necessary
PE prevention
prophlyactic AC for high risk patients
mechanical methods: compression stockings
lifestyle modifications to reduce risk factors for DVT
What is ARF (acute respiratory failure)?
life threatening condition characterized by the inability of the respiratory system to maintain adequate gas exchange, resulting in hypoxemia and/or hypercapnia.
In ARF, primary dysfunction involves either a failure in
oxygenation or ventilation
Describe Type 1 respiratory failure
aka oxygenation failure.
marked by a PaO2 less than 60 mmHg with normal or low PaCO2.
commonly due to conditions like pneumonia, pulmonary edema, or ARDS, where there is impaired gas exchange at the alveolar level.
Describe Type 2 respiratory failure
aka ventilatory failure
presents with PaCO2 greater than 50mmHg and often associated with hypoxemia
causes include COPD, neuromuscular disorders, or CNS depression affecting respiratory drive
clinical presentation of ARF
dyspnea, tachypnea, cyanosis, AMS, use of accessory muscles
abnormal ABGs: indicating hypoxemia and or hypercapnia
management of ARF
treat underlying cause, support oxygenation and ventilation
-supplemental oxygen. in cases of ventilatory failure or severe hypoxemia unresponsive to oxygen therapy alone, may need mechanical ventilation
NIPPV can be used sometimes to avoid intubation
Pharm interventions for ARF
bronchodilators for bronchospasm
corticosteroids for inflammation
abx for infection
diuretics for fluid overload
What is ARDS (acute respiratory distress syndrome)?
severe, life-threatening condition characterized by the acute onset of widespread inflammation in the lungs. It can result in impaired gas exchange and can lead to significant respiratory fialure. Often seen in critically ill pts and can be triggered by various direct or indirect insults to the lunge, such as pneumonia, sepsis, trauma, or inhalation injury
describe pathophys of ARDS
marked by increased permeability of the alveolar-capillary barrier, leading to pulmonary edema that is not caused by cardiac failure. This results in reduced lung compliance and impaired oxygenation. The hallmark of ARDS is the rapid onset of severe dyspnea, hypoxemia, and bilateral infiltrates on chest imaging that cannot be attributed to heart failure or fluid overload.
the categories of ARDS are based on
degree of hypoxemia: mild, moderate, severe
determined by the PaO2/ FiO2 ratio while on PEEP of at least 5cm H2O
mild vs mod vs severe ARDS
mild: PaO2/ FiO2 ratio between 200-300mmHg
mod: between 100-200mmHg
severe: less than 100 mmHg
management of ARDS
supportive care with mechnical ventilation using lung-protective strategies.
-includes low TV ventilation (6ml/kg of predicted body weight) and maintaining plateau pressures below 30cm of H2O to prevent ventilatory-induced lung injury
prone positioning has been show to improve oxygenation and outcomes in severe cases
other: conservative fluid management to minimize pulmonary edema
tx of underlying causes
prevention of complications (DVT, stress ulcers)
Pharm has limited roles. NMB in early severe ARDS to improve oxygenation
What is acute lung injury?
critical condition characterized by acute and persistent lung inflammation, leading to increased pulmonary vascular permeability and non-cardiogenic pulmonary edema.
It is an intermediary state between normal lung function and ARDS, with ALI being a less severe form.
defined by the acute onset of hypoxema, AEB PaO2/ FiO2 of less than 300mmHg, bilateral infiltrates, and absense of left atrial HTN (which differentiates it from cardiogenic pulmonary edema)
pathophys of ALI
direct or indirect lung insults
direct: pneumonia, aspiration, inhalation injury
indirect: systemic inflammatory responses such as sepsis or pancreatitis
the resultant damage to the alveolar-capillary membrane increases its permeability, allowing protein-rich fluid to leak into the alveoli, impairing gas exchange
clinical presentation of ALI
acute onset dypsniea, tachypnea, refractory hypoxemia
crackles due to alveolar flooding
ABG- hypoxemia and resp alkalosis initially
bilateral infiltrates without evidence of LA HTN or significant pleural effusions
management of ALI
supporitve care. underlying cause.
mechanical ventilation with low TV to prevent further lung injury
PEEP is used to maintain alveolar recruitment and improve oxygenation.
fluid management to maintain adequate perfusion while avoiding overload