POTD: Bringing a needle to a knife fight

Hello friends,

For my final clinical content based POTD, I wanted to summarize the steps for a nightmare event: the pediatric can’t intubate, can’t oxygenate scenario.

Resus residents, do you ever find yourself just glossing over the small bag in the corner of the bottom drawer of the airway cart when you do your daily check? The one labeled with the piece of tape that says “jet insufflation”? Maybe in the back of your head you have a vague idea that it’s supposed to be used for a needle cric in pediatric patients below 8 years old. But that’ll probably never happen right? Well, I’m here to tell you…..you probably are right. But that doesn’t mean that we shouldn’t be prepared for it.

I remember early resus year when I would check that the things on the check list were in that bag, but not actually have the context for how it all pieced together. It wasn't until PGY-2 procedure day when me and my co-residents in our group realized what a blind spot it had been for us. What are these random small syringes with the top off? Why is there the top of an ETT just out and about in here? Well, after reviewing the steps for the procedure, hopefully you can visualize how it all comes together.

Steps

1.     Prep and drape while locating the cricothyroid membrane.

2.     Pierce the membrane with the 14G angiocath directed 30-45 degree caudally.

3.     Advance catheter over needle, hub to skin, and remove needle.

4.     Attach a 7-0 ETT adaptor to top of a 3mL syringe with plunger taken out and attach this apparatus to the catheter.

5.     Attach a BVM to ETT adaptor.

6.     Take a deep breath (but don’t forget to also give your patient one), you did it.

It’s a relatively simple procedure, just with insanely high stakes.

Because I’m very much a visual learner:

Here’s a quick 1:52 min video: https://www.youtube.com/watch?v=F_PV7N2c2pQ. Note how the video does it is probably slightly different than how we would with our own makeshift kit here. Sorry for the potato quality but it’s short and gets the point across.

And lastly, I wanted to summarize a recent article written in June (the First10EM link below) that actually advocates doing a surgical approach with a scalpel and not going down the needle cric route for kids like what is traditionally taught to us. The author was also featured on this week’s episode of EMRAP going over this topic. Basically multiple professional societies have come out with contradictory guidelines over the use of needle vs surgical cric, which is not helpful. Data is super limited because of the rarity of this event in this population. Pediatric case reports seem to demonstrate a lack of success of the needle approach as the first line and that complications are to be expected even when the airway is established. This is seen again and again in adult studies as well.

The author then advocates that having the peds surgical cric approach in your toolbox is the best guarantee of achieving a definitive airway in this scenario with the least complications.

In children less than eight years old, the cricoid membrane may be too small so the horizontal incision step is discarded. There is also a higher risk of transecting the entire trachea with the horizontal incision. Instead in the peds surgical approach, you would just do a vertical cut through the trachea (though no more than 2 tracheal rings as this can make repair afterwards more difficult).

Would love to know what other peds providers think about this stance. It does seem like it is branching a little bit farther than what we’re comfortable with, but this is where the art of medicine comes in because the paucity of data out there.

References

https://www.ncbi.nlm.nih.gov/books/NBK537350/

https://first10em.com/the-pediatric-cant-intubate-cant-oxygenate-scenario-use-a-knife/

https://www.tamingthesru.com/blog/acmc/needle-cricothyrotomy

Breathe easy friends!

Intubating Asthmatic Patients

Asthma is Greek for panting, which is a fitting translation for a patient that presents with a severe asthma exacerbation. We try to avoid intubating these patients because they are prone to compilations such as pneumothorax, mucus plugging, and increased morbidity and mortality. 

However, there are specific situations when you may consider intubating an asthmatic patient. One reason is that your patient may not be improving despite maximal medical therapy, such as BIPAP, albuterol, ipratropium, magnesium, epinephrine/terbutaline, ketamine, etc. Another reason is that your patient may now be altered, and have worsening work of breathing, and vital sign abnormalities. Remember that a “silent chest” is a poor prognostic indicator; you may not hear wheezing because they are not moving any air. 

If you choose to intubate, there are tricks to maximize your success and optimize your management of your patient on the vent. 

• Use a large ETT (8-9) because it reduces airflow resistance and can facilitate procedures later (such as bronchoscopy). 

• Ketamine is a useful induction agent because of its bronchodilatory effects. It may also be useful if you choose delayed sequence intubation. 

• High airway pressures can cause hypotension after intubation, so consider giving volume if there is a current or prior history of hypotension. 

• If hemodynamics are compromised consider giving an epinephrine drip. It is considered a systemic bronchodilator that can provide hemodynamic support as well as bronchodilation. 

• Keep a low respiratory rate when bagging or on the vent (6-8 breaths/min). Giving them time to exhale will decrease the chances of air trapping and pneumothorax. Another way to do this is to increase the I:E time (1:4 or 1:5). 

• If the vent is alarming, troubleshoot (DOPES mnemonic) but be suspicious for mucus plugs, pneumothorax, or breath stacking. If they are breath stacking, disconnect them from the vent and push on their chest to help them fully exhale.  

A quick note about auto-PEEP and breath stacking: Auto-PEEP refers to trapping gas in the lungs during respiration. This occurs when one breath can’t be fully exhaled before the next inhalation. This trapped gas causes additional positive pressure, known as “auto-PEEP” in the chest which is typically higher than the PEEP set on the ventilator. This process predisposes patients to develop a pneumothorox. 

Thanks for reading!

Ariella

POTD: Intubating the Pregnant Patient

Intubating a pregnant woman is intimidating because you have two patients to consider. Physiologic changes in pregnancy can affect intubation so it is important to plan ahead.

Both ventilation and acid-base status change during pregnancy. As progesterone rises, there is an increase in tidal volume, which results in maternal respiratory alkalosis. This creates a gas gradient to allow for the transfer of CO2 from the fetus to the mom. This maternal hypocarbia causes uteroplacental vasoconstriction, which can cause fetal hypoperfusion and hypoxia. This creates a very delicate acid-base balance that is exacerbated by increased fetal oxygen consumption and CO2 production in the third trimester. In addition, the diaphragm is pushed up by the gravid uterus reducing the mother's functional residual capacity by 10-25%. As a result of these factors, pregnant patients have a shorter safe apnea time and can desaturate quickly.

Progesterone also decreases the tone of the lower esophageal sphincter. Combined with increased intraabdominal pressure from the gravid uterus, pregnant patients are at higher risk for aspiration. For these reasons, you should be careful with bagging and consider intubating in a semi-upright position. This position also has the benefit of taking some pressure off of the patient's chest and IVC.

Anticipate a difficult airway in pregnant patients. Failed intubation is 8x more likely than in the general population. Human placental growth hormone secreted in pregnancy increases blood flow to the upper airways. This results in edema and hyperemia of the airway, causing it to be smaller and more friable. For this reason, you should prepare a smaller caliber ETT. Rocuronium and succinylcholine have been studied with similar efficacy. Induction agents therefore depend on patient specific factors.

TLDR: 1. preoxygenate well due to shorter safe apnea time. 2. Consider a smaller ETT for a narrower and more friable airway. 3. Limit aspiration risks by decreasing bagging if possible 4. consider intubating patients in a semi-upright position.

Thanks for reading! 

Ariella

References: 

https://rebelem.com/respiratory-failure-and-airway-management-in-the-pregnant-patient/

https://www.nuemblog.com/blog/intubating-the-pregnant-patient

https://www.uptodate.com/contents/airway-management-for-the-pregnant-patient