AG2-Mechanical ventilation Flashcards
What are 4 main reasons for mechanical ventilation?
Respiratory failure, apnea, hypoxia, and respiratory muscle fatigue
What are the 2 levels of pressure support provided with BiPAP?
Higher inspiratory positive pressure and lower expiratory positive pressure
What is tidal volume?
Volume of air delivered with each machine breath
What is a normal tidal value?
6-10ml/kg
What is PEEP?
Positive pressure applied at the end of expiration. Can be used to increase functional residual capacity and improve overall oxygenation.
What is a normal PEEP value?
5-10 cm H20
What is the flow rate?
How fast each breath is delivered by the ventilator. Normal value of 40-80 L/min.
What are 3 methods for weaning the patient off the ventilator?
T piece, SIMV mode, and pressure support trials
What is a T piece?
Oxygen delivery system that is used in place of the mechanical ventilator for short periods of time to assess the patient’s tolerance and respiratory drive off the ventilator.
What is SIMV mode?
Synchronized intermittent mandatory ventilation; rate of the ventilator is gradually decreased allowing the respiratory rate to be a combination of ventilator and spontaneous breathing.
What are pressure support trials?
Pressure is gradually decreased to allow the patient to increase is or her own tidal volume.
What is the proper cuff inflation pressure?
20-30cm H20
Most common traumatic lung problems caused by mechanical ventilation?
Barotrauma: positive pressure from the ventilation distends the lungs and causes the alveoli to rupture.
Volutrauma: excess volume being pushed into the lungs shifts fluid into the alveolar spaces causing lung injury.
Lung injury: prolonged ventilation can decrease the lung’s ability to produce surfactant and increase inflammation in the tissue.
What is a common complication of mechanical ventilation?
Ventilator associated pneumonia (VAP)
What are signs of VAP?
Fever, crackles, increasing WBC, excessive sputum.
Interventions to prevent VAP?
- elevate the head of the bed at least 30 degrees.
- frequent oral care
- oral suction to prevent aspiration
- pulmonary hygiene (chest physiotherapy, postural drainage, and positioning).
Causes of high pressure alarms going off?
Suctioning, coughing, biting on ET tube, obstruction of the ventilator tubing, and pneumothorax.
Causes of low volume alarms going off?
Air leaks (flat pilot balloon on ET tube, low cuff pressure)
How long should you oxygenate a patient prior to suctioning with a closed ventilation system?
30-60 seconds
What is minimum PEEP used on a ventilator?
5
What is the max PEEP used on a ventilator?
20
PaO2, PaCo2, pH, and SaO2 signs of respiratory failure?
PaO2< 60mmHg
PaCO2> 45mmHg
PH< 7.35
SaO2< 90%
How is the tidal volume goal calculated?
Weight based 7-9mL/kg (ideal body weight)
How many liters of oxygen can be delivered with high flow nasal cannula?
Up to 60 liters per minute
What are the benefits of high flow nasal cannula?
Less drying and less nosebleeds because the oxygen is 100% humidified and heated
What is the PEEP effect of high flow nasal cannula?
Every 10 liters = 1 of PEEP
Nursing interventions when patient is on BiPAP?
Prevent skin breakdown and monitor for vomiting
What are indications for intubation?
Chest wall not moving, cyanosis, GCS < or equal to 8, decreased oxygen saturation, abnormal ABGs (PCO2> 50), unable to protect their airway d/t decreased mental status, general anesthesia
Explain color changes with CO2 detector confirmation after intubation?
Purple- problem, could be in the lungs
Yellow- CO2 is being blown off
Why do we need to give PPIs and H2 blockers to ventilated patients?
To prevent stress ulcers
How often does CHG mouth care need to be done for ventilated patients?
Every 2-4 hours
How often should we assess for suctioning on a ventilated patient?
Q2H
How long can an ET tube be in place?
10-14 days
What ventilator modes will do all the work of breathing for the patient?
Volume controlled, pressure controlled, and assist control.
What ventilator modes allows the patient to start the work but then takes over the work if needed?
SIMV
What ventilator modes allows the pt to do some or most of the work but then assists to finish the work?
Pressure support, BiPAP, and CPAP
What is PIP?
Peak inspiratory pressure; Dynamic pressure need to fully inflate the lung (overcome resistive and elastic forces of the lung); how hard the ventilator has to work to blow up the lungs.
What can an increased PIP indicate?
Patient is going into ARDS
What is the goal for PaO2 with a patient with ARDS?
> 55
What is the goal for PaCO2 for a patient with ARDS?
40-50
Ventilator adjustments: If PaO2 is low then ?
Increase FiO2 and/or increase PEEP
Ventilator adjustments: If PaO2 is high then?
Decrease FiO2 and/or decrease PEEP
Ventilator adjustments: If PaCO2 is high then?
Increase RR and/or increase Vt (tidal volume)
Ventilator adjustments: If PaCO2 is low then?
Decrease RR and/or decrease Vt
T/F End tidal should be the same as PCO2?
TRUE
What are some complications of mechanical ventilation?
Cardiac problems, lung problems, GI problems, infection, msl deconditioning, ventilator dependence, and self extubation.
Why should we monitor for I&Os, weight, and hydration status in a ventilated pt?
PEEP increases intrathoracic press leading to a decrease in cardiac output resulting in hypotension causing RAAS to be activated and leading to fluid retention/decreased urine output.
Why should we teach ventilated patients to avoid using the Valsalva maneuver like straining during a bowel movement?
It can further increase intrathoracic pressure
What are symptoms of failing ventilator weaning trials?
Sternomastoid activity, diaphoresis, nasal flaring, cyanosis, tachypnea, abdominal paradox, tachycardia, intercostal recession, and supresternal and supraclavicular recession.
What causes a high PIP alarm to go off and how do we fix it?
Developing decreased compliance; fix by evaluating for ARDS RRT to adjust
How often should we monitor a patient after extubation?
Every 5 min for signs of respiratory distress or sudden closure of the airway
