Help
Options
Didn't know it?
click below
click below
Knew it?
click below
click below
Don't Know
Remaining cards (0)
Know
retry
shuffle
restart
0:00
Embed Code - If you would like this activity on your web page, copy the script below and paste it into your web page.
Normal Size Small Size show me how
Normal Size Small Size show me how
MechVentStudyCards
Mechanical Ventilation Trivia / Study Cards
| Question | Answer |
|---|---|
| What is Ventilation? Q1 | Movement of air into and out of the lungs. |
| What is mechanical ventilation? Q2 | Using a piston driven, micro processor or pneumatic devices etc. to move air into and out of the lungs. |
| What are the functions of mechanical ventilators? Q3 | To provide movement of gases into and out of the lungs by mechanical means, piston movement microprocessors etc. |
| How does a mechanical ventilator provide ventilation? Q4 | Mechanical ventilators alter the person's inspiratory airway pressures only (expiration is passive). Ventilators use flow, pressure, volume, or time on inspiration. |
| What is flow? Q5 | How quickly a volume is dlvd & is calculated by dividing the amt of volume by amt of time. (Volume/Time) The mechanical ventilator delivers a particular volume or pressure set or given amount of time. Volume in L/M & Pressure in Time (Inspiratory Time) |
| What is meant by volume controlled ventilation? Q6 | When the mechanical ventilator delivers a set tidal volume, when a set flow is achieved. (ex. tidal volume 500mL with a flow of 60 L/M **remember pressure will vary |
| What is meant by pressure ventilation? Q7 | When the mechanical ventilator delivers a set pressure when a set time is achieved. (ex. pressure control 30 - with a inspiratory time of 1 sec.) **remember, volume will vary |
| What will cause a pressure variation in volume controlled ventilation? Q8 | When a volume ventilator dlvrs a preset Vt, the pressure will vary according to the pts pulmonary compliance (lungs) and the pts RAW (ET tube vent circuit, airway obstruction, etc.) |
| What will happen during volume ventilation if the pts lung compliance decreases (lungs get stiffer)? Q9 | Remember: During volume ventilation the volume is set, so a decrease in lung compliance will cause an increase in the amt of pressure to dlvr the set volume. |
| What will happen during volume ventilation if the pts airway resistance decreases? Q10 | In volume ventilation the volume is set, so a decrease in airway resistance will cause the pressure required to dlvr the volume to decrease. |
| What will cause a volume variation in pressure controlled ventilation? Q11 | When pressure controlled ventilation dlvrs a preset pressure, the volume will vary according to the pts pulmonary compliance and RAW. |
| What will happen during pressure controlled ventilation if the pts lung compliance decreases? Q12 | During pressure controlled ventilation, the pressure is set, so a decrease in lung compliance will cause a decrease in volume (not pressure). |
| What will happen during pressure controlled ventilation if the pts RAW decreases? Q13 | In pressure controlled ventilation the pressure is set, so a decrease in RAW will cause an increase in volume to the pt. |
| What is airway resistance (RAW)? Q14 | Airway resistance is the change in pressure divided by flow. Raw = (PIP – Pplat) / Flow. |
| What is pulmonary (lung) compliance? | Lung compliance is the change in volume divided by the change in pressure (How easily a lung will inflate) CL = Change in volume |
| What is meant by decreased compliance? Q16 | A decrease in compliance means lungs are stiffer (not as easy to inflate) caused by many restrictive diseases (ARDS, Pulmonary Fibrosis, etc.) |
| What is meant by increased lung compliance? Q17 | Increased compliance beyond normal means the lungs lack elasticity or the ability to snap back to original position (COPD, as shown by increase total lung capacity on pulmonary function test). |
| What is static compliance? Q18 | Static compliance is the measurement of lung compliance absent the flow from the mechanical ventilator. Cstat = ΔV / Pplat – PEEP. |
| How is inspiratory flow stopped on a mechanical ventilator? Q19 | By setting an inspiratory pause or hold, by dialing in an inspiratory hold of about .5 to 1 seconds (it is also called plateau pressure measurement) |
| What does a plateau pressure measure? | The lung pressure absent flow, but will include PEEP (Positive End Expiratory Pressure). |
| Does PEEP effect static compliance measurements? Q21 | Yes, static compliance is the change in volume divided by the change in pressure, since PEEP is left in the lungs it must be subtracted to get a true static compliance measurement. CLST = Change Vol/Change Press = Vt (Plateau - PEEP) |
| What is dynamic compliance? Q22 | The measurement of compliance when flow is present so that compliance as well as RAW is measured, and by subtracting PEEP. CDYN = Change Vol/Change Press = Vt (Peak-PEEP) |
| What is I:E Ratio? Q 23 | Inspiratory/Expiratory ratio is determined by the flow when using (volume ventilation) and determined by the I-time when using (pressure ventilation). |
| How is volume ventilation affected by I:E Ratio? Q24 | Volume ventilation uses L/M flow to determine I:E ratio. The faster the flow is sent in, the longer the time is allowed for expiration. ie (60 L/M flow will have a shorter inspiratory time than 40 L/m) |
| What is the significance of a shorter inspiratory time? Q25 | A shorter i time may be needed if pt needs longer times to exhale, such a COPD pts, b/c of the increased compliance. (They also have decreased flow rates; hence the need to increase the flow to speeds compatible to their needs). |
| What is total cycle time (TCT)? Q26 | The amt of time that the ventilator has for both inspiration and expiration, which is determined by the preset rate. |
| What are the total cycle times for the following rates: Rate = 15 Rate = 12 Rate =10 Q27 | Total cycle times are at follows: Rate = 15 = tct = 4 sec. (60 sec/15 sec) Rate = 12 = tct = 5 sec Rate = 10 = tct = 6 sec |
| How does inspiratory time percentage affect total cycle time? | The amt of time you set on the ventilator to deliver inspiration as part of the TCT. ie: Vent Rate 12 (TCT = 5 sec) *Itime% = 50% 5 x .5 (50%) Itime in sec. would be 2.5 sec. |
| How does inspiratory time percentage effect expiratory time? Q29 | Itime % effects Itime directly - expiratory time would be the remaining time left over. Ie: (Vent Rate 12) = TCT = 5 sec Itime% = 50% = Itime = 2.5 sec Ex time = 2.5 sec TCT = 5 sec |
| How do I adjust Itime % if the mechanical ventilator does not have this option in volume ventilation? Q30 | In some volume ventilators the flow control will adjust inspiratory time percentage. **Remember flow is how fast you tell the ventilator to send in a preset volume. Flow = V/T |
| What are the commonly used Itime percentages? Q31 | 20%, 25%, 33%, 50% |
| How are inspiratory / expiratory ratios (I:E ratios) determined by Itime %? Q32 | 20% Itime = 100/20 = 5 parts Inspiration is 1 part always (unless inversed) I:E ratio would be 1:4 1 + 4 = 5 parts |
| What are the I:E ratios for the commonly used Itime percentages? Q33 | 20% Itime = 100/20 = 5 parts = I:E of 1:4 25% Itime = 100/24 = 4 parts = I:E of 1:3 33% Itime = 100/33 = 3 parts = I:E of 1:2 50% Itime = 100/50 = 2 parts = I:E of 1:1 |
| What is control mode ventilation? Q34 | When the ventilator delivers a preset Vt at a preset rate. (Not commonly used) Will not allow pt to trigger own breaths - Pt will be locked out from vent (should be on sedation or resp depressants). |
| When is control mode used? Q35 | When pt needs to be sedated and paralyzed because of fighting the ventilator. |
| What is assist control ventilation? Q36 | When a preset volume and preset rate is dialed in, but also allows the pt to initiate his own resp rate **will not lock pt out of ventilation |
| What will happen when the pt initiates his own efforts on assist control mode? Q37 | The ventilator will give them the preset volume, which is set on the ventilator. (Remember; both assist breaths and control breaths will yield the preset volume). |
| Why is assist control made not used for weaning? Q38 | Because the set volume from the machine will be delivered. We would not know what the pts own (true) volume is -- ie: Vol set = 500 Control breath = 10 Assist = 10 (both x 500) |
| When is assist control mode used? Q39 | To provide full support without locking the pt out of the ventilator and can be also used as backup rate for apnea. |
| What is Synchronized Intermittent Mandatory Ventilation (SIMV)? Q40 | SIMV is when the ventilator will dlvr a preset volume and rate, and will also allow pt to trigger vent and allows pt to establish own Vt. |
| Why is SIMV often called a weaning mode? Q41 | Because if the pt initiates a breath, we can see what his true spontaneous Vt is, but will also give preset volume and rate if the pt doesn't initiate. |
| What will happen if the pt initiates a breath at exactly the same time as a set timed breath? (On SIMV) Q42 | Because the machine is synchronized the vent will take over the spontaneous breath and make iot an assisted breath. (This eliminates fighting the ventilator) or ASYNCHRONY |
| Why do we use SIMV? Q43 | SIMV will provide partial support while allowing the pt to breath spontaneously (which is first step in weaning). |
| What is pressure control ventilation (PCV)? Q44 | When the ventilator dlvrs a preset pressure (not volume) by using a preset rate. **Remember: volume will vary, according to pts compliance and resistance. |
| How is flow determined on PCV? Q45 | Flow is determined by inspiratory time set on the ventilator and also rate when using pressure control ventilation. |
| Why do we use pressure control ventilation? Q46 | Pressure control ventilation is used when you have excessive high airway pressures on volume ventilation -- ie: diseases such as ARDS - decreasing lung compliance. |
| What will happen when the pts lung compliance improves on pressure controlled ventilation? Q47 | When lung compliance improves on PCV you will see and increase in the pts Vt -- **Remember: pressure is set - volume will vary). |
| What is inverse ratio ventilation (IRV)? Q48 | When PCV is used with Itime belong than Etime. (ie: 1.5:1 or 2:1 I:E ratio) |
| Why would we use PCV with inverse I:E ratio? Q49 | To help oxygenation with ARDS pts by extending the time the pressure remains in the lungs before expiration is allowed. |
| Why is inverse ratio ventilation used with pressure control? Q50 | Because of the danger of barotrauma from extended times used to oxygenate. This way we can control how much pressure is in the airway - (mean pressure). |
| What is pressure regulated volume control (PRVC)? Q51 | A unique mode in the fact that you can have a set Vt and the ventilator will regulate the lowest possible pressure to deliver that volume. |
| How does the ventilator regulate the pressure in PRVC mode? Q52 | The ventilator automatically alters the pak flow and Itime, when it senses a changing airway resistance or lung compliance. |
| What is airway pressure release ventilation (APRV)? Q53 | When a person is allowed to breath spontaneous at and elevation CPAP level, then this elevated level is released to form an expiration. |
| What is normal APRV release time? Q54 | Usually between 1 and 2 seconds. |
| When would we use Airway Pressure Release Ventilation? Q55 | APRV is used for ARDS, and Restrictive diseases as an alternate to volume ventilation. |
| What is high frequency oscillatory ventilation (HFOV)? Q56 | A ventilator that delivers the highest rates possible in the range of 240 to 1800 / per min (4 to 30 Hz). |
| How does the HFOV ventilator deliver high rates? Q57 | The HFOV produces piston driven movement that passes perpendicular to the ET tube. |
| When do we use HFOV? Q58 | It's used on infants and neonates because of its high rates and lower volumes. (Sometimes used in adults when conventional ventilation has failed). |
| What are common settings for the HFOV? Q59 | Initial Settings = 1) Mean Airway Pressure (MAP) - set a little higher than conventional settings. 2) Flow (Bias) - 20 L/M 3)Power (amplitude) - 5 to 6 4) Itime % - 33% 5) FiO2 - 100% 6) Frequency (HZ) - 8 to 15 |
| How do I adjust the HFOV for increasing and decreasing PaCO2 measurements? Q60 | For increasing PaCO2 first you: 1) increase power (amplitude) 2) then decrease frequency (HZ) For decreasing PaCO2 first you: 1) decrease power (amplitude) 2) then you can increase frequency (HZ) |
| How does decreasing the HZ or frequency in HFOV cause a decrease in PaCO2? Q61 | In HFOV the piston movement is what causes volume displacement. The slower the piston, the larger the volume entering pts lungs, which would result in lower PCO2. |
| What is pressure support ventilation? Q62 | When a pressure is applied to the airway during spontaneous breathing to overcome airway resistance from the ET tube & circuit, and also causes augmentation of spontaneous Vt. |
| When is pressure support used? Q63 | Used for all spontaneous modes of ventilation, such as SIMV, to help spontaneous volume, because they are breathing through circuits, and ET tubes to trigger breaths. |
| What is the difference between pressure support and pressure control ventilation? Q64 | Pressure support is initiated by the spontaneous breathing effort, while pressure control is controlled by the vent operator or timed (Itime and rate). |
| What is proportional assist ventilation (PAV)? Q65 | PAV is a new option on some vents that automatically changes the pressure support according to the volume, compliance, and resistance of the pt. |
| What is adaptive support ventilation (ASV)? Q66 | ASV is an option that changes the number of breaths delivered by the machine and pressure support, according to the pts breathing pattern. |
| What is volume assured pressure support (VAPS)? Q67 | VAPS is a combination that assures a Vt by combining pressure support with volume assisted cycles. |
| What is continuous positive airway pressure (CPAP)? Q68 | CPAP is pressure applied and used for spontaneous breathing pts which would keep alveoli open to prevent atelectasis by improving Functional Residual Capacity. |
| When is CPAP used? Q69 | CPAP is used for spontaneously breathing pts to help improve oxygenation because of refractory hypoxemia caused by intrapulmonary shunting. |
| What is positive end expiratory pressure (PEEP)? Q70 | PEEP is basically leaving pressure in the lung after exhalation to keep lungs inflated and prevent the lungs from collapsing. |
| Why do we use PEEP? Q71 | PEEP is used for oxygenation due to refractory hypoxemia caused by intrapulmonary shunting. (Keeps alveoli open for further lung recruitment and increased surface area). |
| What is the difference between CPAP and PEEP? Q72 | CPAP is PEEP applied to spontaneous breathing pts. PEEP is used during mechanical ventilator breaths when there is a rate. |
| What should we watch for when using PEEP? Q73 | Since PEEP is airway pressure inside the lungs, we must be aware of the detriments of positive pressure. Decreased cardiac output, decreased urine output, increased Intracranial pressure (ICP). |
| How do we know PEEP is being detrimental? Q74 | PEEP can have a direct correlation to decrease blood pressure if used to the extreme, which would cause a decreased blood flow to kidneys hindering urine output. ICP monitors should be in place for head injury pt when using PEEP. |
| What is peak inspiratory pressure (PIP)? Q75 | PIP is the total pressure it takes the mechanical ventilator to deliver a preset Vt. (Including both RAW and lung compliance). |
| What is mean airway pressure (MAP)? Q76 | MAP is the average airway pressure during a ventilator cycle. |
| What affects mean airway pressures? Q77 | MAP, because it is in the airway, is affected by the Itime -- how long pressure is in airway. Rate and ITime and PEEP - which remains in the airway while set. |
| What is plateau pressure? Q78 | Pplat is the pressure remaining in the lungs, after the flow is stopped by an inspiratory or inflation hold (pause). It is used to measure static compliance. |
Created by:
Beccaboop
Popular Respiratory Therapy sets