Selective Digestive Decontamination decreases MODS

About 10 years ago we were doing SDD on all our ventilated patients, but we stopped because of a lack of good evidence of efficacy and the fear of developing bacterial resistance. A new Critical Care Medicine systematic review shows that SDD decreases MODS but not mortality.

It's not enough to change our practice, but it's still interesting nonetheless how the same stuff keeps coming up.

Proton pump inhibitors increase the risk of clostridial infection

Patients who were treated with PPI while being treated for clostridial infection had a 42% increased risk of recurrence
http://archinte.ama-assn.org/cgi/content/full/170/9/772

High dose intravenous magnesium drip may help patients with aneurysmal SAH

There was a significant decrease in delayed ischemic infarction in the group that was treated with a high dose magnesium drip to keep the serum magnesium level between 2 and 2.5. There was no statistically significant difference in mortality or GCS, although there was a suggestion to that effect. The morbidity of giving magnesium was nil, and it may help.

Make sure the patient is comfortable at night and can sleep

What happens to you if you’re awoken every 10 minutes? That’s what happens to an ICU patient. If a patient is up all night, they’ll be tired the next day when the time comes to try to extubate. Also, make sure that at night they have adequate ventilator support. Don’t try to wean someone when they’re sleeping.

Always try to allow a patient to say "Good bye" and "I love you"

Often in critically ill patients we are concentrating on stabilizing a patient. If they’re in respiratory distress our priority is getting them intubated. But remember that there will be times that this may be the last time they ever get to speak to their loved ones. So if you can, make sure that you get their family in there so the patient can say “Good bye” and “I love you.”

Endotracheal tube removal requires ability to protect airway

Is a gag reflex present?

Can the patient cough?  (Consider using a "white card" test.  Disconnect the patient from the ventilator, place a white index card in front of the patient, and if they can hock a loogie onto the card, they have an adequate cough)

Are the patients secretions managable?

Can they protect the airway?  (They do NOT need to be completely alert to do this)

Treatment of Septic Shock is all a guideline

I went to a talk by one of the authors of the Surviving Sepsis Campaign. He went through all the points in the SSC. His major point is that the endpoints, such as CVP 8-12, SVO2 >70, MAP>65 are all starting points. You need to use some clinical judgment. For example, let’s say you have a young patient who has a good vascular system. You get the MAP to 60, and the patient starts to pee. Should you push the pressor just to get the MAP to 65? Not necessarily. On the other hand, if you have an elderly patient with atherosclerosis, you may need a higher MAP

More on Nasotracheal intubations

It's important to use Afrin or Neosynephrine in whatever nostril you pick.  You can soak some q-tips in an Afrin solution and then put them in  the nose.  This will vasoconstrict and help prevent bleeding.  Another trick is to get a small nasal trumpet, and coat it with lidocaine jelly.  Stick it in the nose, and leave it there.  Then get a bigger nasal trumpet and coat it with lidocaine jelly.  Give it time to take effect.  Use more Afrin.

Then use the Endotrol tube (see picture) if you have one.  Pull the little loopy thing and that pulls the tip anteriorily.

Nasotracheal intubation tip

If you're stuck doing a nasotracheal intubation, the major problem is getting the tube to go anterior so it'll intubate the larynx.  We do have the "Endotrol" tubes which have a loop that you can use to pull the tube anterior, but if you don't have that, here's a trick.

Use lots of lidocaine jelly into whichever nostril you pick.  Put the tube in.  When you get to the pharynx, inflate the cuff--that'll push the tube anterior.  Advance the tube, and then when you're in the larynx deflate the cuff and intubate past the cords.  Then inflate the cuff again.

Patients don't fight ventilators, ventilators fight patients.

If a patient is having trouble with a ventilator, the first responses of nurses and physicians is often to increase sedation which will make the doctors and nurses feel better, but will ultimately work against the patient.  Sedated patients can't be weaned off a ventilator and every day you're on a ventilator is another day you're on a ventilator.

The first response to a patient "bucking" a vent or "fighting" a vent, is to work with the ventilator settings.  Is the patient getting enough tidal volume?  Is the patient getting too much?  Does the patient need more flow?  If the patient is on volume control ventilation might he be better suited on pressure control (or vice versa)?  Does the PEEP need to be adjusted?

Try those first.  Increase sedation as a last resort.

Weaning

Everybody is fond of weaning people off the ventilator--slowly decreasing the respiratory rate or pressure support.  But does it make any difference?

No.

What makes a difference is DAILY spontaneous breathing trials, ideally paired with sedation vacations.  In fact, the lecturer I went to today suggested that weaning people off the ventilator might be counterproductive because it could tire people out for their spontaneous breathing trial.

So if you want to wean someone off of a ventilator, go ahead.  Just don't tire them out, and make sure that they have their spontaneous breathing trial every day. 

Auto-PEEP

Auto-PEEP.  We've all heard of autopeep.  Most times when people think about it, they're thinking that it's "intrinsic PEEP," and they know it's bad--and they'd be right.  But what causes it and what makes it happen?

Look at the image below

This is a flow vs time diagram.  Above the line is inspiration, and below the line is exhalation.  Note how the flow below the line does not come back to zero.  This means that the patient starts their inspiration before they have a chance to completely exhale.  Try it--it's not comfortable.

What does this mean for a patient on a ventilator?  Well it means that the ventilator will try to give a breath before the patient is done exhaling, and airway pressures will go up and tidal volumes may drop. 

What causes it?   Auto-PEEP is caused by one of three things.

1. High minute ventilation.  Minute ventilation is caused by high respiratory rate and/or high tidal volumes
2. Increased I:E ratio.  If the inspiratory time is too high, relative to the expiratory time, the patient will not have enough time to exhale (see the graph above)
3. Airway trapping, like in asthma or COPD

So how to treat it?
To treat it, you have to think of the three reasons above.

1. High minute ventilation.  This is the easiest to deal with.  Decrease the minute ventilation.  First start with decreasing the respiratory rate, and then the tidal volume.
2. Increased I:E ratio.  Again, decrease the respiratory rate, this will increase the inspiratory time.  You can also try increasing the flow in the ventilator cycle so more of the air goes to the patient at the beginning of the breath.  
3. Airway trapping.  Decreasing the respiratory rate will give time for the air to leave the lungs (think asthma).  Also, increasing the PEEP can help in COPD-related airway trapping.  The way this works, is if, say the auto-PEEP is 10 cm from airway trapping, and the patient has to initiate a breath, they need to pull at least -10 cm before the ventilator will trigger.  Adding PEEP to this will counteract this.  So, say, in this example there is a PEEP of 7, the patient will only need -3 cm to trigger the vent.