A few things that everybody needs to know about the LTV ventilator

As you've already read in a couple of blog posts back, I have a Pulmonetics LTV 1150 ventilator.

This ventilator is a portable Home ventilator that is also capable of being used in the ICU.

It's very pleasant to listen to it's drone as it's not too loud, or too quiet, and it provides me with smooth ventilation.

I am posting this blog post because there may be other people whether they might be a patient, or a parent of a child who is on this ventilator, and I want to explain a few things about this ventilator in hopes to help them if they are having issues with the ventilator.


This post is going to be very very long, so be warned.

Here I go droning on again.

Yeah, I know, I use the word drone quite a bit, as do I use the word wee quite a bit, for example, "He's a wee bit wheezy," or "During the wee hours of the morning, the patient desatted to 74% and the nurse came in to discover that He'd taken his oxygen off and was playing with the tubing."

I use other words quite a bit, but I have noticed I do use Wee and Drone a LOT.

LOL!

But anyhow, I'm getting off topic here.

I'd like to talk about a few things related to the LTV ventilator, and what might be the problems.

First I'd like to talk about the DISC/SENSE alarm.

There is an alarm on the ventilator known as a "DISC/SENSE," alarm.

This alarm could mean several things.

It's triggered by either a disconnection of the flow transducer cables that are connected to the ventilator circuit.

These are the two small tubes that you will find  on the side of the wye at the end of the circuit.

These essentially tell the ventilator when the patient's breathing, how much flow they're generating, the tidal volume that they are generating, or what volume is coming back to the ventilator after a machine or patient breath, and several other parameters.

These tubes may become unscrewed at the ventilator end, and even the slightest bit can induce a DISC/SENSE alarm.

Trust me.

I've had it happen to me.

I've connected a circuit, and gotten the dreaded "DISC/SENSE," alarm, and then I've traced the sense lines back from the wye to the ventilator to find that thel one of the lines were on slightly crooked, or  that one of them was not snug, and then once I fixed that, the alarm stopped!

It's very important that when you are going to attach these to the ventilator's flow transducer ports, that you sort of counter screw them, or counter turn them somewhat to the left, before you connect them to the transducers, and then you will notice that they screw themselves on when you do that.

You are not finished though.

You then need to tighten these the rest of the way,  until they are propperly secured onto the ventilator, but Not so tight that when it's time to remove them for a circuit change you can't get them off.

Then you have a problem, and it may in fact take hemostats to get these things off once you've done that, and you can actually break the plastic connectors at the end of these tubes.

This is best avoided by just getting them snug on the connections, and thennot cranking them as tight as you can get them.

These sensors must be snug, and on there straight, or you will get the dreaded  DISC/SENSE alarm.

Another issue that could cause the alarm to sound is the tiniest drop of water in the lines.

We're going to refer to these two transducers with the yellow and white color coded connections as sense lines from now on.

The smallest drop of water in the sense lines is going to confuse the ventilator, and do a couple of things.

One line being blocked will cause the ventilator to not give the breaths.

It will autocycle, and will give tiny breaths at upwards of  100-120 times per minute, but these breaths are not going to be enough to actually ventilate the patient.

This is a HUGE  problem, and must be solved immediately.

The other sense line, if obstructed will cause the ventilator to become confused to where It will not know when to stop delivering the breath, and so breaths will be stacked and this is also very very dangerous.

If condensation develops in the sense lines, you can simply press what is known as the "Manual Breath Button."

On the bottom portion of buttons, you will find this button over to the right, at the fifth button over.

It is to the left of the "Control Lock," button.

Two things are going to happen when you press this button.
1: The ventilator is going to administer an extra breath.

2: The ventilator will send what's known as a "Bolus," of air throughthese two sense lines and this will clear out the water in the tubing.

You might repeat this two to four times and then the DISC/SENSE alarm should stop.

This could also be caused by water in the exhalation valve sense line.

What I do to prevent so many DISC/SENSE alarms is something that I have found works for me, and that does not cause volume loss, pressure loss, or incorrect readings from the ventilator.

On the exhalation side of the ventilator,which on my Non-Heated wired ventilator circuit I have a long aerosol tube that You'd connect to a Large Volume Nebulizer, connected to this side, and I have an extra Humidification chamber that I use as a water trap.

On the other side of the trap,  or the water chamber, I have the section of the ventilator circuit that goes to the exhalation valve.

Now, on the side of my ventilator's pole stand, where the basketis that you hold stuff like the Extra charging cables, there's a little grasp that I put my tubing for the exhalation valve in, and It keeps it off the floor, and the exhalation valve is not hanging down to where a lot of water can develop in the tubing.

This keeps water that might get into the large tube that my exhalation valve is connected from getting into the valve, and I've found that now that I've done this, I can turn my  Heater up to the maximum setting.

That is the only setting I'm comfortable at.
Now I want to  inform you that my heater doesn't have a temp probe or a heated wire, so there's no way to precisely set the temperature.

It's a small dial, and so I have no idea what the temp is.


This  humidifier is more sutable for a CPAP or BiLevel machine and Not sutable for the ventilator patient, but It's what my DME has, so they don't have the exact heater where you set the precise temperature, so I just have to make do.

Turns out, I'm not the only patient that has that issue.

If you are wondering, my Heater is a Fisher & Paykel HC150!

Now, usually from the research I've found, you're not going to find this in use with a home vent circuit.

It's more likely to be used for a patient with a PAP therapy device who doesn't use  a built in humidifier.

But anyhow, if you happen to be a patient or a caregiver who got something like this thing for your ventilator, This blog post is certainly for you.

You might recall the nights you've woken  up to the alarm, and you've gone to troubleshoot, and when you picked up your exhalation valve, water was just almost pouring out, and this is a complicated fix, because if you tap it against something, you're going to dislodge the diaphragm, and that's a real pain to fix, and so your PEEP is not going to be maintained, and that could take hours to fix.

You have to shake the tubing, and hope the water comes out enough to stop the alarm.

I don't know, the manual breath button might fix this, but really, It's best not to have to press the manual breath button if you ask me because it does administer an extra breath, and it's usually safe, but could cause distress in the patient because of the extra breath that they did not initiate.

So now that I have a water trap in my circuit, and I have the exhalation valve mounted on the small grasp  as I will call it, the water trap will collect most of your condensation.

it's important to empty this water trap every single day, and to clean it as well.


There are other reasons for your DISC/SENSE alarm, but these are the main two.

Other reasons although rare could be a hole in the sense lines, or broken connectors.

The ventilator itself may be malfunctioning and the components that read the flow inside the vent may be malfunctioning.

If you suspect this, and have tried all your other options above, than you need to contact your DME to have them come out and evaluate the issue.



The next issue I would like to talk about is the top filter on the left of your ventilator.

If this filter needs to be cleaned whilst the ventilator is actually ventilating a patient, it's very important that when removing it, you be aware that there is a fan inside of this area and if you stick something in there and it touches that fan, your ventilator is going to give you the "Hardware Fault!"

Immediately, GET WHATEVER IS IN THERE OUT.

Turn off the ventilator, and then turn it back on, and HOPEFULLY, this alarm resolves.

When you do this, if the patient can breathe, they should be disconnected from the circuit and allowed to breathe, but if they have difficulties or cannot, your manual resuscitation bag is there for that reason, and should be used.

If the patient is on a Lot of PEEP for example 10cmH2O this bag shouldhave a PEEP valve connected to it to maintain that PEEP.

If you're not cleaning the filter and you  get a hardware fault, the first thing you do is look at this the filter and see if maybe big brother or sister of the baby had put something in there.

YOU MUST check this first, because if this is not removed, the ventilator is going to stop functioning, and you're going to get analarm that you won't be able to silence and you will then have to call the DME and they'll have to either resolve the issue, or possibly send the ventilator in for repair.

This is  avoidable.

Hardware fault may be induced by other reasons, but the main reason is something has touched that fan that's behind that filter.

If this happens and when you remove the object from the ventilator you're still getting a hardware fault, you need to switch to the back up ventilator immediately, and turn off the ventilator that's having this issue because otherwise the ventilator's going to be trying to run but it can't because of this hardware fault and this could damage the ventilator even worse.

In most instances once you get whatever is in the fan out the alarm will resolve and you can turn off the ventilator, and turn it back on and it will stop displaying the hardware fault, but in rare situations, the ventilator will need to be serviced.




The next issue I want to discuss with you is the ventilator's battery.

There are two types of external batteries for the ventilator.

There is what is known as the "Sprint Pack," which is  white and that runs for about three to four hours and it consists of two batteries.

There are two test buttons on these batteries and you can press these and lights will display, and depending on how many lights are displaying  will depend on how much battery that you have left in each of the batteries.

It is very important that this battery remains plugged into the wall when not in use.

It will last much longer if the battery is not left to discharge.

A lot of times, this battery will be connected to the backup/transport ventilator, and this will be connected to the wall outlet at all times.

There is also the big batteries which can usually power the ventilator for 8-10 hours and these should also be kept charged, and kept in a dry room.

The ventilator also has it's own internal battery, but this battery usually only lasts for like 30-45 minutes depending on the ventilator's settings, and the patient's respiratory demand.

it is very important that this internal battery only be used as a backup.

If you're out and you have used your external battery, this internal battery will be the emergency backup, and hopefully this will not be necessary, but if it is, you shouldbe prepared to manually ventilate the patient, because this battery does not last long.
You might also decide to use this battery in the tub room, or if you're just taking the patient outside for a few minuets, but never use this battery on a trip to the Dr's. or to the hospital, because it will not last you long.



The important thing about these batteries, especially the Sprint Pack is that these remain charging whenever they are not in use.

If you're going to store the backup/transport ventilator somewhere, you need to keep both the battery and the ventilator plugged in at all times.

Otherwise, your batteries will completely discharge, and this will become a problem when you have to use the ventilator.



The next thing I would like to talk to you about is something very important that might be confusing to somebody.

If you turn the ventilator off, like if your patient is getting off the ventilator for a short period, when you hold down the Standby button, the ventilator once powered off is going to sound a very loud alarm.

This signals that the ventilator has been powered off and I feel this alarm is very very important because in the event that somebody tries to turn off the ventilator the operator needs to know that the vent is off, and not ventilating.

To silence the alarm, you Press the "Silence/Reset," button.

Now, even when you have done this, you are going to note that the "VENT INOP," Light is still illuminated.

This is another important alert to alert you the caregiver, that the ventilator was recently turned off.

This will remain on for 10-15 minuets, and then it will turn off.


The next thing that might confuse some people who are new to the ventilator is the flashing alarm message even when the alarm had resolved and the audio alarm has ceased.

This is another very very important indicator that was built in the vent for a reason.

All right.

Scenario:

Baby Sean coughs and triggers the HIGH PRESSURE alarm.

All right.

Sean has coughed and now that he's no longer coughing the ventilator senses that the Inspiratory Pressure is back under the HIGH AIRWAY PRESSURE alarm limit.

The alarm has stopped sounding.

But then Sean's Mother comes into the room to see that the alarm is no longer sounding, but she sees the Red alarm Indicator, "HIGH PRESS," and it is flashing.

Why?

This is very important in that it has alerted Sean's mother that there was an alarm that did sound and even though the situation has self resolved when Sean stopped coughing, that alert is there to indicate that yes, at some point Sean did trigger this alarm.

So how is this alarm cleared?

it's simple.

You press the SILENCE/RESET alarm button, and then you will see the ventilator measured parameters rotating through each value once again.

Most ventilators have this function.

In the event that the Evita XL alarms after the alarm has resolved, the ventilator will still display the message in white letters so that the RT will see what alarm was triggered, and until that message is cleared, this will be displayed.

The Hamilton ventilators, and the Trilogy ventilators also have this function.

I feel that these features are very important in all ventilators.




All right.

Let's say that you are a nurse caring for a patient  on the LTV ventilator.

You might be asked to chart values such as the PIP, the MAP, the VTE, the I:E Ratio, and the actual Frequency.

Well, on the top of the ventilator's front panel, there is the message display screen where these values are continuously rotated through.

But what if you need to manually rotate through these to chart at your own pace.
Well, you can simply press the "SELECT," button and you can then manually review these settings, and can do this without having to rush to chart a value before the rotation continues to the next value.

The order is as follows!

F: which equals the Actual Frequency!

VTE: That is the exhaled Tidal Volume.

VE: That is the Minute Ventilation.

I:E This is your Inspiratory to Expiratory Ratio.

VCALC: This is the calculated flow that the ventilator calculates according to the Tidal Volume you set, and the Inspiratory Time!

In other words, this value will only appear if the patient is in VOLUME CONTROL ventilation.
If Sean was set to Pressure Control this value will not be available, and there will be no need to chart it.

Between the VCALC and the PIP, you might see messages that indicate that alarms are turned off, for example, "LMV ALARM OFF," or "HIGH F OFF," depending on whether any alarms are turned off.

PIP: This is your Peak Inspiratory Pressure.

MAP: This is  the reading for your MEAN AIRWAY PRESSURE.

PEEP: This is your actual Positive End Expiratory Pressure, or PEEP.

NOTE: Remember previously how I'd mentioned the painful task of fixing your exhalation valve if you tried to tap it to get the water out?

Well, if your baby is set at 10 of PEEP, and your ventilator is reading the PEEP as 2, That set PEEP is not being delivered, and THAT IS A BAD THING.

If the Low PEEP alarm is turned on,  It will certainly alarm.

Now, let's say that Sean's nurse is done charting, and wants to resume the rotation of parameters.

Well to do this, simply press the  "SELECT," button two times in rapid succession.

Now the rotation continues.


Another issue I want to discuss is the variation of parameters according to what is set, and what you get.

What you have set and what you get may be a wee bit off.

So, let's give some settings here, and we'll talk about this carefully.

We have Sean on a Respiratory Rate of 30, on a Tidal Volume of 95, on a Pressure Control of 18, which is dimmed out because we're not using Pressure control, an Inspiratory Time of 0.5, on a Pressure Support of 15, on a Sensitivity of 1, with a High Pressure Alarm Limit of 40, a Low Pressure Alarm limit of 4, and a Low Minute Ventilation Alarm of 0.1, and with  a set PEEP of 10!

All right, now usually the Low Pressure limit is not set below the PEEP, but sometiems in the Home Care Setting this happens.

All right.

Now, we've got Sean on his ventilator.

He's sleeping comfortably, and Occasionally might take some breaths, but let's say that for the most part, He's riding the ventilator.

All right.

So, the nurse is charting the ventilator settings, and the actual parameters.

The Tidal Volume that the ventilator reads may be somewhat different than the actual setting.

This depends on the Compliance, and the Resistance of the ventilator circuit, of Sean's trach tube, of his airways, and of his small lungs.

In other words, if Sean's nurse sees a VTE, of 86 instead of 95, this isn't too unusual.

Now if there is a huge variable in the VTE, for example, she sees a VTE of 30 or 40, there would definitely be cause for concern, and this should be immediately  checked out.

The PEEP may be a little bit off too, as well as the  PIP.

One or two cmH2O is not uncommon.

However, if the PEEP was set at 10cmH2O and Sean's nurse charts a PEEP of 1cmH2O there is definitely an issue and this MUST be checked out.

Of course, in most cases the High and Low PEEP alarms need to be active.



Another important function that I want to discuss are the two different locking functions.
If you notice, exactly to the left of that black rotary wheel there is a "CONTROL LOCK," button.

This is to lock the ventilator so that it cannot be accidentally adjusted, and so that nothing can be changed.

There are two levels of the  Control Lock.

The first one is the EASY lock.

If this was set in the internal menu then when the ventilator is locked, to unlock it you just simply press the lock button.

If the ventilator is in HARD UNLOCK, you will have to hold this button down for three seconds to unlock the ventilator.

If you are not sure what level is set in the Internal Menus, you can simply press the "CONTROL LOCK,"  button, and if the ventilator was locked when you pressed it, the ventilator will either unlock, and the green light on the button will go off, or you will see that light flash, and the message "LOCKED," will display in the message window that has your measurements and alarm indications displayed.

If the LED flashes and you see "LOCKED," when you press the "CONTROL LOCK," button, you will have to hold this button down for three seconds, and then the ventilator will be unlocked.

This locking function is there for safety.

If Sean's Big brother Aidan comes in to look at the ventilator and then tries to press buttons, the ventilator if locked will prevent any changes.

If children are in the house and there is a higher risk of setting changes there really should be a "HARD LOCK," programmed into the ventilator so that the risk of changes is reduced.

It's important to note that even when the ventilator is locked the Select button can still be used to manually view parameters, and to stop and restart the rotation of the parameters.

The alarm silence button is still functional as well.

At this point, I've covered several important things in regards to the Pulmonetics LTV ventilator, and I hope that this was helpful.

If anybody does have any questions you can comment and I will answer these questions.

In the future I can discuss other topics and at a point in time, this will occur, but I wanted to stress some very important things that I've thought of, and some that I've had issues with.

Well, mainly the DISC/SENSE alarm.

That was hard to resolve, but I give God praise for eventually helping me with this issue.

I'm very thankful.

One of the most important things to remember is to first look at the patient.

The ventilator could be going off saying "LOW PRESSURE," and that means that the pressure is lower than the set Low Airway Pressure Alarm limit.

It is Highly likely that this could be a disconnect, or a leak.

So if you look at the patient, and trace the circuit all the way to the machine, you can usually see where the disconnection is.

The baby could  have the whole circuit off and playing with it, or the large tubing could have popped out of the wye.

High Pressure alarms that sound but then quickly stop, are most likely a cough, or a forced exhalation.

You also MUST have a manual resuscitation bag, or better known as the Ambu Bag ready in the event that you cannot readily identify the problem.

If this happens, just take the ventilator circuit off, and bag the patient until somebody can identify the issue that is causing the alarms.

I hope this helps,  may God bless you and keep you, as well as all you come into contact with, including your family, your relatives, and your friends.


God's love is Perfect, and we should cherish that,and give our lives to him, fully devoting ourselves to glorifying him, and to being a witness to others about what He has done, is doing now, and what he will do for us, and will do for them when they accept them into their hearts.