questions with answers
Reasons for Mechanical Ventilation - ANSWER: ✔✔- Acute Respiratory Failure
- Ventilatory Failure - not moving adequately but perfusing
- Oxygenation Failure - moving air but perfusing inadequate
- Combined Ventilatory and Oxygenation Failure
Acute Respiratory Failure - ANSWER: ✔✔- Classified as blood gas abnormality
- PaO2 less than 60 mm Hg (however, less than 80 is hypoxemia)
- PCo2 greater than 45 mm Hg with acidosis.
- Sa02 less than 90%. (pulse oximetry)
- Can be caused by ventilatory failure, oxygenation failure or a combination of both.
- Whatever the cause, the patient is hypoxemic.
Ventilatory Failure - ANSWER: ✔✔- Can result from inadequate chest wall movement not allowing
enough air movement into and out of the lungs, which causes carbon dioxide to be retained.
- Muscle weakness that occurs with some neuromuscular diseases such as Myasthenia Gravis, ALS, brain
stem dysfunction can cause inadequate ventilation.
- Table 32-2
- Shallow resp, agonal resp, probs with brain
Oxygenation Failure - ANSWER: ✔✔- Oxygenation failure results when air moves in and out the lungs
without difficulty, but does not oxygenate the blood sufficiently.
- Poor diffusion of oxygen at the alveolar level.
- Air that is low in oxygen
- Abnormal hemoglobin that fails to bind oxygen.
- Table 32-3
,Combined Ventilatory and Oxygenation Failure - ANSWER: ✔✔- Hypoventilation and poor gas diffusion
with or without poor lung perfusion.
- Examples are ARDS and combined heart failure and lung disease.
- With ards, surfactant is washed away and pt will have slower breaths and lungs fdont' move adequately
and lungs become stiff and as alveoli are affected , we don't have good oxygenation
Clinical Manifestations (ASSESSMENT) - ANSWER: ✔✔- Dyspnea - difficulty breathing
- Orthopnea - can't breathe while laying down. characterized by number of pillows it takes for pt to lay
on to breath properly
- Hypercarbia - too much CO2
Pallor - turning pale or grayish (later sign)
- Cyanosis - turning blue or purple (later sign)
Restlessness - will happen with hypoxemia (early sign)
- Confusion
- Labored breathing
- Agonal respirations- An abnormal pattern of breathing characterized by gasping, labored breaths that
are not effective. Not moving air
--- Can be the result of brain injury, respiratory failure, cardiac arrest
Diagnostics - ANSWER: ✔✔- Pulse Oximetry - measured on finger, earlobe, nose, forehead (SaO2 95% -
100%)
- ABGs - most reliable way to tell about gas echange and oxygenation
- End-Tidal Carbon Dioxide Monitoring - amount of CO2 that is exhaled (normal value is 35-45). When pt
is being intubated is the most definitive way to show proper placement without x-ray
- CXR - can visualize lungs and see if pt is properly intubated, if needed
Pulse Oximetry (cannot replace abgs) - ANSWER: ✔✔- Noninvasive measurement of oxygen saturation
(SpO2).
- Measures the percentage of oxygen bound to hemoglobin (normal 97%)
- Can be used for continuous monitoring or spot check.
, - Can reduce the need for frequent sampling of arterial blood
- Can it completely replace ABGs?
When is Pulse Ox Not Accurate?? - ANSWER: ✔✔- Vasoconstriction meds - epinephrine, dopamine
- Elevated carboxyhemoglobin (smokers)
- Shock - decreased perfusion and compensatory mechanisms cause vasoconstrictions
- Severe anemia - not enough circulation hemoglobin
- Arrested - blood is shunted from periphery to heart to sustain bp
Anything causing decreased perfusion
- Thick acrylic nails
End-Tidal Carbon Dioxide - ANSWER: ✔✔- Measures the level of CO2 at the end of exhalation by
changing colors
- Measured via
--- Endotracheal tube
--- Nasal or oral airway
Nursing Diagnoses related to mechanical ventilation - ANSWER: ✔✔- Impaired Gas Exchange - look at
abgs
- Ineffective Breathing Pattern - look at resp rate (12-20 (or 28 for resp failure), depth, and effort [should
be full even and unlabored with chest movement symmetrical]
- Ineffective Airway Clearance - abnormal breath sounds (crackles, wheezing, coarse, moist non-
productive cough, et tube that keeps getting clogged with secretions)
- Impaired Spontaneous Ventilation - apnea, agonal breathing, decreased rate of 10 or 8
- For unsuccessful weaning - dysfunctional ventilatory weaning process
Goals/Objectives - ANSWER: ✔✔- ABG's return within normal value - don't say normal value say a PaO2
greater than or equal to 80, pH between 7.35 and 7.45, and PaCO2 between 35 and 45
- Resp 12-28, full, even, and unlabored
- O2 sat >/ 92% (lower may be acceptable depending on the pt and doctor's order)