what is passive atelectasis? name four things that can cause this?
the result of persistent use of small Vt
- 1. general anesthesia
- 2. shallow breathing
- 3. reduced surfactant production
- 4. inadequate nutrition
atelectasis in a hospitalized patient can be the result of what? (6)
1. neuromuscular disorders
2. heavy sedation
3. upper or lower abdominal or thoracic surgery
4. bed ridden patients
5. spinal cord injury
6. hx of malnutrition
what types of lung diseases can lead to atelectasis? name 5 (ABCCE)
those w/ increased mucus production
- 1. asthma
- 2. chronic bronchitis
- 3. emphysema
- 4. c.f
- 5. bronchiectasis
what are some symptoms of atelectasis? (7)
- 1. increased RR
- 2. inspiratory rales
- 3. bronchial BS
- 4. reduced BS
- 5. hypoxemia (due to shunt)
- 6. tachycadia (heart tries to compensate for hypoxemia)
- 7. fever (if pneumonia develops)
What might you see on a x-ray for a patient with atelectasis?
- 1. opacity
- 2. signs of volume loss
- due to: displacement of interlobar lung fissures, crowding of blood vessels, air bronchospasms, elevated diaphragm, shift of trachea, heart or diaphragm (shift towards it, pneumothorax would push it away)
there would be white solid figures
What are 4 different types of lung expansion therapies?
3. CPAP (continuous positive pressure ventilation)
4. PEP (positive expiratory pressure)
1. what two types of pressure does "transpulmonary pressure" consist of?
2. The greater the transpulmonary pressure the more the _____ ____ ____.
1. transpulmonary pressure = alveolar pressure - pleural pressure
2. the more the alveoli will expand.
(this will allow the pressure gradient to open up the lungs )
how can each of the four lung expansion therapies change transpulmonary pressure? (2)
1. I.S - decreasing the surrounding pleural pressure by a deep spontaneous inspiration
2. IPPB, PEP, CPAP - increasing the alveolar pressure by applying positive pressure
what can you do for a patient that is at minimal risk for atelectasis? high risk? and high risk, but not able to do I.S?
1. minimal risk : deep breath coughing, frequent repositioning, early ambulation, (or IS)
2. high risk : I.S
3. positive pressure (IPPB)
with IPPB, the more pressure you give them the more ____ the patient will get as well.
how many cmH20 does the patient need to turn the bennet IPPB machine on?
-1 to -2 cm H20
what does the pin do on the bennett machine? what do u have to do to manually give the patient a breath?
when the holes line up the patient recieves a breath. the pin allows gas to flow. push the pin up to manually give them a breath.
1. What do the terminal flow nobs help with?
2. What happens to inspiratory time if you increase flow?
3. How many LPM does it take to stop the bennett valves cycle (stops flow of gas)
1. helps to compensate for leaks
2. increasing flow will make inspiratory time decrease
3. 1-3 LPM will stop the bennett valve, therefore stoping the flow of gas
what are four common problems that can happen with IPPB?
1. difficult to turn on or turns on w/o patient initiation
2. inspiratory time too short of too long
3. unit cycles off prematurely due to obstruction
4. unit will not cycle of due to leak
(patient may not be making a tight enough seal)
what are some things you should monitor while administering IPPB therapy?
RR, expired volume, peak flow, pulse, sputum, mental function, skin color, breath sounds, BP, SP02, ICP, Xray, & subjective response
what happens to flow when transpulmonary pressure is equal to atmospheric pressure?
flow is zero
For PEEP to work airways pressures are kept ____ atm pressure at all times. how is this accomplised?
ABOVE atm pressures.
PEEP device that allows air out of the circuit only until some set pressure above atm is reached.
1. what happens when the pressure in the PEEP circuit decreases to its new baseline?
2. what happens as the next breath is inhaled?
1. exhalation ends and the volume in the lung (FRC) is larger than it was prior to application.
2. the end inspiratory volume will be higher, because the same volume will be inhaled but there was a larger volume in the lungs at the beginning of the inhalation.
how does PEEP help the alveoli?
because the alveoli that were likely to collapse due to a lack of surfactant are not allowed to do so because the added pressure at the end of exhalation splints or holds them open
PEEP and CPAP are normally used with what type of patients?
PEEP- pt normally on mechanical vent
CPAP- pt is spontaneously breathing
*they both are changing your baseline to maintain openess at the end of exhalation
what are the two types of PEEP devices ?
Orificial resistors - (has continuous flow) generates PEEP by obstructing gas flow. dependent on expiratory flow rate
threshold resistors - creates PEEP by the use of a spring that keeps preset level of pressure on exhalation valve w/in a specific flow rate . able to maintain PEEP at a constant level.
what are 5 types of threshold resistors that provide PEEP ?
inflated balloon, emerson water seal, weighted ball, spring loaded, or a magnet
what are the normal PEEP pressures?
a patient on CPAP needs to maintain ______.
what do flow resistors on PEEP do?
increase the flow rate past the point where the resistance of the exhalation vavle can allow gas to leave. because the flow fills up the circuit faster than it is vented out, back pressure creates positive pressure.
During PEP therapy the patient exhales against a ____-_____ flow resistor.
what happens when the pt exhales against the fixed-orifice flow resistor?
pressure in the airways is raised, which shifts the gas from those alveoli that were easily inflated during inhalation to those that are atelectatic.
Is PEP or PEEP continuous?
PEP is NOT. PEEP is continuous.
how would you instruct a pt to use PEP ?
when are the alveoli opened up with PEP therapy?
pt takes a moderatly deep inhalation through their nose and then exhales against the fixed orifice resistor.
atelectatic alveoli are inflated during the EXHALATION phase. NOT INHALATION!!
does PEP or PEEP therapy require a pressurized external gas source?
PEP - NO
PEEP - YES
does EPAP produce the same mechanical or pressure effect as PEP when a fixed orifice resistor is used?
how does EPAP increase the work of breathing?
draws negative during inspiration and can increase the work of breathing because there is a larger gap from expiratory pressure to inspiration