Mechanical Ventilation Flashcards
What are the two types of mechanical ventilation?
-Negative pressure (not used in acute care setting)
-positive pressure (pushes air in)
What are the two subgroups of positive ventilation?
-Volume ventilation (predetermined tidal volume (Vt) is set. Pressure is determined by the pt and vent together and varies w/each breath.)
-pressure ventilation (peak inspiratory pressure & the volume is determined by the pt/vent w/each breath)
pressure vent is for inhale only & helps prevent alveoli collapse by keeping the pressure up
What are the two volume assisted vent MODES?
-A/C Vent (assist-control,*max support)
•preset tidal volume & RR
•Pt can initiate own breath but vent will do all work & deliver set volumes.
•used commonly in resp failure, ARDS, Paralysis
-SIMV (Synchronized intermittent mandatory vent)
•preset tidal volume & RR but Pt can initiate own breath W/own tidal volume
•commonly used for Pt weaning or strengthening lungs/WOB.
Pressure support vent setting
•won’t have preset volume
•Pt must be able to initiate own breath
•positive pressure is added to inspiration
•typically used for Pt weaning
•flow rate of + pressure is greater than the force of spontaneous breath —>
^ o2 reaches alveoli
Pressure control vent setting
PCV: gives breath w/set pressures. Pt can control RR & volume
Pressure control inverse ratio
PC-IRV:
•”last ditch effort setting”-Renteria
•extra inspiratory time than expiratory time allows for increased alveolar oxygenation
•short expiratory cycle keeps alveoli open
•need deep sedation d/t abnormal breathing pattern
•used commonly w/ARDS Pt’s who are hard to oxygenate
Airway pressure release ventilation
APRV:
•”not as much sedation/gentler setting” -Renteria
•allows spontaneous breathing but has preset CPAP
•no set Vt
•Delivers set of rapid inspiratory pressures (extra puff -think eye Dr test)
•good for Pt’s w/collapsed alveoli
Pressure regulated volume control
PRVC:
•dual modes together - full support (preset pressure & volume)
•sedation needed but it’s a gentler mode
Ancillary vent settings
“Peep those alveoli open” 🫁
-PEEP:
• + pressure applied at end expiration
•opens alveoli/prevents collapse
•range is 3-20cm h2O (5cm is natural occurring/healthy person)
•main goal of PEEP: improve oxygenation while decreasing the Fio2
- Warning* -increased PEEP levels Can cause barotrauma to alveoli and hemodynamic instability
warning the higher the peep the higher risk for decreased BP d/t intrathoracic pressure on the heart
Alternatives to Vents: CPAP
Continuous positive airway pressure :
•similar to PEEP but delivers continued expiratory pressure
•maintains 5cm H2O
•common uses: sleep apnea, CHF, COPD exacerbation
*caution in Pt’s w/cardiac impairment
Alternatives to Vents: BiPAP
Bilevel positive airway pressure:
•two levels of support (considered life support)
•high inspiratory & low expiratory pressures
•common Pt’s: COPD, CHF, RF, sleep apnea
•last ditch effort to prevent intubation
*contraindications: need to be conscious, not vomiting, no facial trauma or recent head sx
Hi-flow NC
•fills dead space
•delivers set flow rates
•less risk of mucosal damage
•can achieve peep (1cm H2O for Q 10L)
•similar to Bi-pap w/o claustrophobia
Vent complications (alveolar)
Alveolar hypoventilation: leaking cuff, low pressures, increased secretions or obstruction
Alveolar hyperventilation: Pt hyperventilating over set rate, tidal volume set too high or rate set too fast
Nursing considerations: Vent
•pain control/sedation
•reposition Q2hr/PRN
•oral care/suction
•maintaining alarms
•trach care
•monitor trends/vitals/labs
•participate in weaning trails/sedation vacations
Indications for intubation
•Resp distress is #1 indicator
•prolonged period of apnea (TBI, sleep apnea, drugs)
•Trauma/airway obstruction
•high risk aspiration/ineffective airway clearance(overdose/drunk)
Risks/complications of intubation
•broken teeth
•spinal cord instability (make sure to use jaw thrust maneuver to protect spine)
•inability to intubate (swelling, fat, bleeding, vomit)
ET Tube placement
2cm above carina
Use stethoscope; listen abdomen, lft lung, rt lung 🫁
Pre-intubation preparation
Bedside: provider, 2 nurses, 2 RT
Equipment:
•wall o2/suction
•ambu bag
•ET tube, stylet, 10ml syringe, appropriate blade
•fiberoptic intubation device
•CO2 detector
•commercial stabilization device
•meds (situational. Gag reflex NEEDS meds)
•ancillary (NG/foley)
Intubation meds : sedatives
•Fentanyl
•midazolam (Versed)
•propofol (Diprivan)
•Etomidate (Amidate)
Intubation meds : paralytic
•Succinylcholine IVP 15secs
•Rocuronium (Zemuron) 15-30secs
What order are intubation meds given?
1st Amidate + 2nd Succ
Or
1st Roc + 2nd Amidate
Nurses role after intubation
•Maintain correct placement
•maintain cuff inflation
•monitor oxygenation(gas exchange. O2 to tissues). ventilation (mechanics, WOB/RR/muscles)
•maintaining tube patency
•suction only when spo2 drops, Pt coughing, resp distress, secretions or increased RR.
routine suctioning can cause tissue damage, dysrhythmias and increased ICP
Two major complications of intubation
•unplanned extubation:
-can l/t death, disability
-use comfort measures
-use soft wrist restraints if needed
•Aspiration:
-Maintain cuff inflation
-suction PRN /HOB 30-45°
-NG/OG tube for intubated pts
