Respiratory Flashcards
<p>4 causes of hypoxia </p>
<p>1. Low PaO@
2. Anemia or abnormal hemoglobin
3. Low cardiac output states
4. Inability to use delivered oxygen ie. cyanide toxicity</p>
<p>6 physiological mechanisms of hypoxemia </p>
<p>1. Low inspired partial pressure of O2
2. Hypoventilation
3. Ventilation/perfusion mismatch
4. Shunt - intrapulmonary vs. intracardiac
5. Low mixed venous oxygen saturations
6. Diffusion abnormality </p>
<p>Etiologies of decreased lung compliance</p>
<p>pneumonia pneumothorax atelectasis mainstem intubation obesity pulmonary fibrosis ARDS congestive heart failure abdominal distension, compartment syndrome kyphoscoliosis </p>
<p>Causes of increased lung compliance </p>
<p>emphysema
open chest
flail chest </p>
<p>Contraindications of NIPPV </p>
<p>1. hemodynamic instability/shock
2. decreased LOC/unable to protect airway
3. inadequate respiratory drive
4. high risk aspiration (UGIB, SBO)
5. facial trauma/burns/surgeries (unable to wear mask)
6. upper airway obstruction
7. inability to clear secretions
8. agitated, uncooperative patient </p>
<p>Indications for NIPPV </p>
<p>1. Cardiogenic pulmonary edema
2. AECOPD
3. Others controversial: pre-oxygenation, asthma </p>
<p>Complications of NIPPV </p>
<p>pressure necrosis of skin
damages to eyes
claustrophobia </p>
<p>Benefits of PEEP </p>
<p>prevent end expiratory collapse of alveoli
recruit non or poorly ventilated alveoli
creates hydrostatic forces that move fluid from airway to interstitium (helps with gas exchange) </p>
<p>Complications of PEEP </p>
<p>overinflation and barotrauma
decreased preload
</p>
<p>Relative contraindications of PEEP </p>
<p>hypotension right heart failure R->L intracardiac shunt increased ICP hyperinflation asymmetric or focal lung disease bronchopleural fistula </p>
<p>How do you detect auto-PEEP (breath stacking) </p>
<p>Clinical: patients fight the vent, dysynchronous
Expiratory sounds heard throughout expiratory phase up until inspiration
Expiratory hold maneuver </p>
<p>What is the definition of ARDS (Berlin 2012) </p>
<p>Respiratory symptoms must have begun within one week of a known clinical insult, or the patient must have new or worsening symptoms during the past week.
1. Bilateral opacities consistent with pulmonary edema must be present on a chest radiograph or computed tomographic (CT) scan. These opacities must not be fully explained by pleural effusions, lobar collapse, lung collapse, or pulmonary nodules.
2. The patient’s respiratory failure must not be fully explained by cardiac failure or fluid overload. An objective assessment (eg, echocardiography) to exclude hydrostatic pulmonary edema is required if no risk factors for ARDS are present.
3. A moderate to severe impairment of oxygenation must be present, as defined by the ratio of arterial oxygen tension to fraction of inspired oxygen (PaO2/FiO2). The severity of the hypoxemia defines the severity of the ARDS:
•Mild ARDS – The PaO2/FiO2 is >200 mmHg, but ≤300 mmHg, on ventilator settings that include positive end-expiratory pressure (PEEP) or continuous positive airway pressure (CPAP) ≥5 cm H2O.
•Moderate ARDS – The PaO2/FiO2 is >100 mmHg, but ≤200 mmHg, on ventilator settings that include PEEP ≥5 cm H2O.
•Severe ARDS – The PaO2/FiO2 is ≤100 mmHg on ventilators setting that include PEEP ≥5 cm H2O.</p>
<p>What is the dosing of norepinephrine (levophed) </p>
<p>0.01-3 mcg/kg/min for infusion
| Once you exceed 0.3-0.4, start thinking about other causes of shock </p>
<p>What is the dosing of push dose epi and how do you make it? </p>
<p>Take 1:10,000 cardiac epi from crash card. 100 mcg/mL
Mix 1 cc with 9 cc of NS = 10 mcg/mL
Duration 5-10 min
Give 0.5-2 mL q2-5 min (5-20 mcg) </p>
<p>What is the dosing of push dose phenyl and how do you make it? </p>
<p>Take 1 mL of phenyl (10 mg/mL), mix in 100 cc bag of NS
= 100 mcg/mL
Duration 10-20 min
Give 0.5-2 mL q2-5 min (50-200 mcg) </p>
