First Pass Intubation: When You Can’t See The Cords

Failure of first pass intubation occurs about 10% of the time. The most common reasons, as I’ve described in a previous article (Avoiding Difficult Intubation Of The Easy Airway), is failure to pre-position the patient or optimally use our intubation tools.

I recently got an email from a first year resident who had elected to turn some intubations over to her instructors when she couldn’t see the cords. The instructors then had the same problems that she had had visualizing the larynx in those particular patients. Her instructors were successful in intubating despite not being able to see well and she was wondering how common it was to have poor visualization of the cords. She was also wondering if she was stepping aside too soon when she couldn’t see the cords. Maybe she should be trying a little longer.

Those were excellent questions. I thought it might be helpful to describe some of the thought process that goes behind the steps I take when I look but can’t see the cords —or when my student can’t see the cords.

Incidence Of First Pass Intubation Failure

Difficult intubation is defined by the American  Society of Anesthesiologists as “the need for more than 3 intubation attempts by a trained provider or attempts at intubation that last longer than 10 minutes”. In 2010, there were an estimated 25 million intubations in the United States and more than 50 million worldwide (1). The incidence of difficult intubation has been reported as 0.15% . That sounds like a small number, but it calculates to 1.5 in 1,000 intubations, or multiplied by 25 million, would theoretically predict 37,500 occurrences per year in the United States alone. (2)

For intubations in Emergency Departments, some studies have shown that more than two thirds (68%) of the intubations were successful on the first attempt, and about 10% of cases required three or more intubation attempts. Less experienced providers tended to require more intubation attempts. In one study of 2,833 patients (3), CA-1 residents had a 14.5% incidence vs 6% incidence for their staff attendings. More than 99% of these intubations were completed orally.

As you can see from those statistics, it’s not just novice intubators who fail to see the larynx on their first intubation pass. When we can’t see the cords during laryngoscopy,  our heart rate and blood pressure instantaneously rises as our level of anxiety soars. We know that first pass success is associated with a relatively small incidence of complications. As the number of intubation attempts increases, the incidence of complications increases substantially.  One Emergency Department study of 1,828 intubations showed that the incidence of adverse events such as hypoxia or physical injury during intubation was about 14% for one attempt, 47% for two attempts,  64% for three attempts, and 71% for four or more attempts (4).

Failure to see the cords on the first pass is scary. When we can’t see the larynx, we don’t know at that moment whether we will be able to see the larynx on the next pass, or if indeed we are starting down the terrifying road to can’t intubate/can’t ventilate.

The 4Ps of Preparation

You can read a more detailed approach to avoiding difficult intubation in my clinical review article in Airway Management (Always Prepare for Failure: 10 Rules for Approaching Difficult Intubation).(5) But it is worthwhile at least mentioning that the  best way to minimize the risk of getting into a situation where you can’t see the cords  is to optimize intubating conditions before you start. Perform the 4 Ps of preparation. For myself, I often find that I am much more likely to encounter difficulty if I have skipped these steps — which is unfortunately tempting to do in today’s fast paced turnover environment.

  • Past medical history:
    • ask the patient for history of any anesthetic problems
    • look at their old anesthesia records when you can
  • Perform an exam: look for potential anatomical problems
  • Position: place the head and neck in the best sniffing position
  • Preoxygenate well: because you never know when you will have problems

However, there is no question that you can do all of these steps and still fail to see the cords on your first try. Assuming you cannot see enough anatomical landmarks to make a reasonable attempt, what should you do next? Note that some of these steps are occurring simultaneously or in rapid succession.

Stop and Ventilate The Patient

Ventilating the patient gives you a moment to think about next steps. This is a big decision point. Most likely your next attempt will succeed, but if not, then you need to be prepared. If intubation attempts continue to fail,  you will need to decide to either:

  • keep trying – and if so what additional tools or helpers might you need
  • wake the patient up,
  • use a supraglottic airway to either proceed with the case or as an adjunct to intubation
  • consider an emergency airway

Now is the time to optimize oxygenation because further attempts at intubation may take time depending on the circumstances. You also need to ensure that your patient’s medical condition, vital signs, and lack of awareness are optimized.

Ventilating the patient immediately verifies, (and reassures), that you are not (yet) in a “can’t intubate/can’t ventilate” scenario. If you can’t ventilate, then you need to immediately jump further down the algorithm of options.

The ease with which you can ventilate should be factored into how long you will continue further attempts and indeed which steps you might take. If my patient is easy to ventilate, and I saw a fair amount of recognizable anatomy, then I will feel more comfortable trying a simple change in head position and a change in laryngoscope blades. If ventilation is difficult, then I’m much more likely to ask immediately for a videolaryngoscope, ask for another intubator to be called as a back up, or consider waking the patient up.

Communicate With Your Team

As you remove the laryngoscope from the patient’s mouth and begin to ventilate the patient, alert your team to what’s going on. If those team members are doing other tasks in the operating room, call them back to the bedside. Now is not the time to be the strong silent type and solve this problem heroically on your own. You want their attention and help before the patient potentially desaturates.

Quickly Assess What Went Wrong

As soon as you abort an intubation attempt you should be asking yourself: “What went wrong?” What could you see? What couldn’t you see? What can you do to make the next time successful? Start planning ahead.

Change Something On The Next Attempt!

The definition of insanity is to do the same thing that just failed again. Unless you had a perfect view of the cords and the light went out on your laryngoscope right before passing the tube, you must change at least one thing on your next attempt.

What Can You Change?

There are many things that you can change on your next pass, and depending on what you saw the first time you may want to change more than one thing.

  • Type or size of laryngoscope blade
  • Use of, or shape of a stylet
  • Position of the patient
  • Sniffing position improved
  • Addition of cricoid pressure
  • Head tilt
  • How high you’ve lifted the head off the bed
  • Height of the bed
  • The technique of how you’re using the blade
    • e.g. positioning of the tip of a curved blade on the hyoepiglottic ligament

Remember you have helpers who cannot read your mind. Talk to them, tell them what you’re doing and how you need them to help.

What If You Can’t See On The Second or Third Pass?

The recommendation of the ASA Task Force on the Management of the Difficult Airway is to limit laryngoscopic attempts to three before switching to an alternative method in order to avoid the risk of considerable patient injury that may occur. The slippery slope that is sometimes encountered is: Is that three attempts by one provider? Does it matter if the first provider is a novice — e.g. does the count start over when the attending steps in? How many times do you then attempt with the alternate method?

Alternate Intubation Methods

Perhaps as soon as a first pass intubation fails, and certainly when a second pass intubation fails, you should at least start running through the back of your mind what alternate methods you have and what you need to do to use them. What equipment might you need? Where is that equipment? When should you send for the equipment? Should I ask for the difficult airway cart? Is there another skilled intubation who might be called?

Get The VideoLaryngoscope

If your facility has a video laryngoscope, think about asking for it to be brought early. Having it in the room, even if you end up not needing it, saves precious moments if you patient does desaturate. The risk of complications rises with each attempt. Being able to switch quickly to the videolaryngoscope decreases the potential for a truly prolonged intubation attempt. You can read more on the techniques of successfully using one type of videolaryngoscope, the Glidescope here (Glidescope: Tricks For Successful Intubation)

Videolaryngoscopy is quickly becoming the tool of choice for when you can’t see the cords. As costs of videolaryngsocopes come down and their availability increases, I predict that they will eventually become the primary tool for first pass intubation. However, at present they are expensive and not everyone has easy access to one.

Use A Bougie

When you don’t have a videolaryngoscope immediately available, the bougie is a wonderful tool for intubation. It must be used carefully to avoid complication, but if you can’t see the cords it offers you a quick solution. You can read more about the bougie and precautions in its use here (The Bougie: Use Wisely To Avoid Rare But Serious Complications)

Supraglottic Airway Assisted Intubation

Using an LMA to assist with intubation is a nice option. A device such as the Fastrach gives you the ability to ventilate during the intubation process. Details on use of the Fastrach intubating Airway can be found here (Tips for Mastering the LMA Fastrach)

Fiberoptic

Intubation with the fiberoptic bronchoscope is best done electively before one starts so that the airway can be optimized with topical anesthesia, and a drying agent. In an unanticipated intubation, consider using the Fiberoptic early rather than later, before the airway is traumatized and excessive secretions stimulated. Blood and saliva in the airway make visualization very difficult.

Prepare Alternate Equipment Before you Start

When I begin an elective intubation, I always have Plan B and C. I try to have at least some of the equipment close by. I will have still in their sterile wrappers:

  • a second type of blade out on my station
  • a laryngeal mask airway of he correct size
  • a bougie in the room

I (and my team) will know where the glide scope is kept for emergencies. If I’m worried about the airway I often have the GlideScope outside the door ready to grab. It saves a lot of time and anxiety to know that I have alternate methods of intubation and ventilation immediately to hand and ready to go.

If I am running to an emergency intubation on the ward, my intubation box contains alternate methods such as a bougie and an LMA. I will often bring the portable GlideScope with me. Especially when dealing with critically ill and deteriorating patients, first pass i intubation success is especially important.

When To Stop Intubation Attempts

It is difficult to know when to change to a different technique, to ask someone else to try, or to stop the attempt. Failure to recognize the potential point of no return on the way to loss of the airway can be very hard. The temptation is strong to protect your ego by proving to yourself, and your audience of staff members, that you are skilled at performing that technique. “This should work, I’ve done it before; I will make it work now.” I’ve watched colleagues repeat spinal attempts at the same interspace over and over without changing anything, yet expecting success with each new needle pass. As has been said, “The definition of insanity is doing the same thing over and over again, expecting different results.”

Another confounding factor in deciding to abandon a technique, or even the entire intubation attempt, is the fact that one simply is not aware of time passing in the middle of an emergency. What seems like 1 to 2 minutes can really be 10 to 15. Force yourself to keep track of the clock. the longer an intubation attempt persists, the risk of complications increases and indeed the risk of of a “can’t intubate/can’t ventilate” scenario increase as well.

flowchart Difficult Airway Society Guideline for Unanticipated Difficult Intubation 2015

Difficult Airway Society Guideline for Unanticipated Difficult Intubation 2015

Working With A Student Who Misses The First Pass Intubation

The resident who emailed me was wondering what criteria should be used for when the student’s first pass intubation fails and when the next intubation attempt should be turned over to the attending. When I’m working with a student, the timing of when I take over will depend on:

  • my assessment as to how much stimulation the patient will tolerate
  • the experience of the student (and their past success rate)
  • the student’s intubation technique
  • how gentle he or she is being with the patient
  • how well she or he is communicating with me

Patient safety comes first. If I have a high risk patient and an inexperienced student, I will do the intubation and demonstrate the techniques with a running commentary. If my student has more experience and has demonstrated previous success, then I will often try to talk them through the changes I think they need to make on the second ad perhaps third attempt.

One important factor, apart from their technique and how gentle they are, that often gives me more patience in giving them another pass is how well they are communicating with me. I am much more likely to approve another pass from a student who tells me what she sees, explains what she thinks she needs to change, and then describes her proposed next steps.

May The Force Be With You!

Christine E Whitten MD, author

Anyone Can Intubate: A Step by Step Guide
and
Pediatric Airway Management: A Step By Step Guide

To Preview Books On Amazon.com Click Below

  Button link to see inside or buy the book Anyone Can Intubate, A Step By Step Guide to Intubation and Airway Management, 5th edition on amazon    Button to see inside or buy the book Pediatric Airway Management: A Step-by-Step Guide by Christine Whitten

References

  1. American Society of Anesthesiologists: Presentation by Chunyuan Qui, MD, CEO of Qscope. Presented at: Elsevier Business Intelligence IN3 West Conference; March 4-5, 2010; Las Vegas, NV. www.velosal.com/?page_id=15.
  2. Cook TM, MacDougall-Davis SR. Complications and failure of airway management. Br J Anaesth.2012;109 suppl 1:i68-i85.
  3. Mort TC. Emergency Tracheal Intubation: Complications Associated with Repeated Laryngoscopic Attempts. Anesth Analg 2004;99:607–13
  4. Sakles JC, Chiu S, Mosier J, Walker C, Stolz U. The importance of first pass success when performing orotracheal intubation in the emergency department. Acad Emerg Med. 2013;20(1):71–78. doi:10.1111/acem.12055
  5. Whitten CE. Prepare For Failure: 10 Rules forApproaching Difficult Intubation. Airway Management. Suppler to Anesthesiology News 2019-2020

Bilateral Tension Pneumothorax: Harder To Diagnose

Tension pneumothorax is a life-threatening emergency. We all know the signs of tension pneumothorax:

  • unilateral breath sounds (breath sounds absent on affected side),
  • thorax may be hyperresonant,
  • jugular venous distention,
  • tracheal deviation to the opposite side,
  • maximum heart sounds shifted to the opposite side, and often
  • tachycardia
  • hypotension

However diagnosis is more difficult if the patient is suffering from bilateral tension pneumothoraces. We think about bilateral tension pneumothorax occurring with trauma cases. Yet the three cases I’ve seen in my career were complications of intubation and emergency airway management. Continue reading

PostObstructive Pulmonary Edema

Patients with postobstructive pulmonary edema (or P.O.P.E.) develop sudden, unexpected and potentially life-threatening pulmonary edema after relief of airway obstruction.  It can be mild or severe. My first experience with it was in 1983.

The Case

In 1983, we didn’t have pulse oximetry, end-tidal carbon dioxide monitoring or even automated blood pressure cuffs. The patient was a healthy 6’3” tall and 250 lbs , 20 year old man. All muscle and clearly in great shape. He had just had knee surgery under general anesthesia and was on the verge of waking up.

He was coughing vigorously on the endotracheal tube. Four people held him down. My resident, fearful he night hurt himself or the team, extubated him while he was still coughing and before he was following commands. Unfortunately the patient was still in stage 2, when the airway reflexes are hyperdynamic.

Within seconds the patient went into laryngospasm, intense spasmodic closure of the vocal cords and other laryngeal muscles. There followed several minutes of struggling to re-establish an open airway. Finally the spasm broke with the use of positive pressure and the patient awoke.

However the mood in the room quickly turned from relief to concern. Our patient started to panic, claiming that he couldn’t breathe. His color was poor. He was wheezing badly, with pink frothy sputum bubbling out of his mouth. He was awake enough to communicate with us but so panicked that he started to fight the team of caregivers. Continue reading

Airway Emergency: Start With The Basics of Airway Management

We have just finished another round of Critical Event Training for my hospital’s Anesthesia and OR staff. One of the scenarios we ran was how to manage a failed airway emergency: the dreaded “can’t intubate-can’t ventilate” airway emergency scenario.

As an instructor, it’s important for me to set the stage realistically. The more real the scenario, the more the providers will learn and be able to apply the information should they ever find themselves in a comparable situation. I must observe as the trainees respond to the emergency, and then help the trainees self-analyze what went well — or not so well — during the scenario. Of course, discussion of how things went during a training scenario always leads to sharing of examples from past real life scenarios. And after 37 years of practice I’ve had a lot of sharable experiences.

One past case we discussed is particularly appropriate for those students around the country who are just beginning to learn airway management because the solution rested in basic airway management techniques. This case, involving an intubation in an ICU patient that turned into a “can’t intubate/can’t ventilate” emergency demonstrates how returning to the basics of airway management can sometimes be the way to save your patient from harm. All illustrations from Anyone Can Intubate 5th Edition. Continue reading

Close Call In Honduras With A Nosebleed

I recently visited Honduras with a Head and Neck surgical team where we had a close call with a potential airway obstruction due to a blood clot. The case illustrates how a provider should never make assumptions, because if those assumptions are wrong, you can endanger your patient.

After a long day in the OR, while we were packing up to leave, a nurse from the ward ran in and said that one of the patient’s who had had a septoplasty that day for chronic sinusitis was bleeding. I immediately started setting up the OR again while our surgeon went over to the ward. Continue reading

Finding PEEP In a Bottle (of Water): Thinking Outside The Box

As you read this I am flying to Honduras with International Relief Team on a head and neck surgery medical mission. I will attempt to post mission updates from the hospital compound, pending internet connections. Participating in a medical mission to the developing world is never easy.

Medical personnel trained in a high tech environment take for granted the complex monitoring devices, multiple choices of drugs, and plentiful support peronnel which simplify our job. When medical volunteers travel to the developing world they are often unprepared for the potential hazards produced by outdated technology, unfamiliar and sometimes poorly maintained equipment, poor sanitation, limited supplies, and a malnourished, often poorly educated population.

Let me give you an example of one rather exciting case from early in my volunteer experience. Continue reading

Hair Style Can Impact Intubation

Healing Little Heroes director dressed as Darth Vader at Ronald McDonald House, San Diego

Our Healing Little HeroesFoundation  founder dressed as Darth Vader at Ronald McDonald House, San Diego

Last weekend I spent time with the charity group Healing Little Heroes at the San Diego Rady’s Children’s Hospital, and Ronald McDonald House. The mission of Healing Little Heroes Foundation is to help pediatric patients in hospitals and outpatient settings to heal emotionally and mentally by appearing as Superheroes. My good friend, and general surgeon, Justin Wu, dressed below as Darth Vader, set up the Foundation.

On this day we arrived in full Star Wars costumes to entertain the kids and their families. I’m dressed as Queen Amidala. Which brings me to the topic of today’s conversation. Can hairstyle impact your intubation or even your anesthetic management? The answer is yes. There is no question that if Queen Amidala needed emergency intubation, that her hairstyle would get in the way. Continue reading

Intubation With Airway Bleeding and Massive Emesis

During intubation, any liquid in the mouth that obscures the view of larynx not only hinders visualization, it risks aspiration. We’re used to being able to rapidly suction the mouth clear or secretions, blood, or vomit and then have a clear view of the larynx. But sometimes, either because of continued profuse airway bleeding or massive emesis, fluid continues to accumulate while we’re watching. How can you manage this situation and successfully intubate? Here I describe two cases, one involving blood and the other massive emesis, that required intubation through a large puddle of fluid. I offer tips and tricks to assist you in your future emergency management. Continue reading

Help! My Anesthesia Machine’s Not Working!

There is nothing quite as scary as being in the middle of administering an anesthetic and having your anesthesia machine fail. In my 36 years of anesthesia practice I’ve had this happen to me a few times. Knowing how to quickly troubleshoot your machine, and knowing how to protect your patient are important, potentially life-saving skills. It helps to have thought through the steps to rescue the situation before it happens to you.

Here I describe how I learned this lesson the hard way on a volunteer medical mission to rural Honduras. When my machine failed, I was poorly prepared and this forced crisis management that I could easily have avoided with a little forethought and preparation.
Continue reading

Codeine Risk In Children, Especially Those With Sleep Apnea

Although the initial FDA warnings about potentially fatal overdose from codeine in children were released in 2012, I’m recently discovered that a few of my surgeon and nursing colleagues were still unaware of the potential risks. Therefore I thought it might be helpful to bring up the topic so people can remind their own colleagues of the risks of codeine in children.

Codeine must be used with extreme caution, if at all, in young children or pregnant women because of variants in the enzymes some patient’s use to metabolize the drug. Continue reading

Potential Tongue Ischemia with LMA Supreme

When we place anything in the mouth, be it an endotracheal tube, oral airway or LMA, we are typically extremely careful to protect the teeth. We take care to avoid cutting the lips with the teeth. But we often take the safety of the tongue for granted. I recently recognized a potential problem while using an LMA supreme that could have caused tongue ischemia if not corrected. Let we show you what happened so you can be on guard with your own patients.  Continue reading

To Extubate, Or Not to Extubate, That Is The Question

Assessing extubation criteria, and then deciding when to extubate a patient safely can sometimes be a difficult decision.

Extubation Criteria

We all know the common extubation criteria:

  • recovery of airway reflexes and response to command;
  • inspiratory capacity of at least 15 ml/kg;
  • no hypoxia, hypercarbia, or major acid/base imbalance;
  • no cardiopulmonary instability;
  • signs of intact muscle power;
  • absence of retraction during spontaneous respiration;
  • absence of a distended stomach.

In other words, you want your patient to be stable, able to breathe without help, and able to protect the airway.

However, sometimes the decision is not so easy. Here I describe a case of a patient who met some but not all of the criteria for extubation. The reason turned out to be due to a rare complication: plugging of the endotracheal tube. However, getting to that solution required working through the extubation algorithm.  Continue reading

Tongue Necrosis From Endotracheal Tube Compression

Image

Tongue necrosis is fortunately an extremely rare complication of endotracheal intubation, but the injury can be devastating. It’s important to recognize the patients at risk and to take precautions when securing an endotracheal tube to decrease the risk of injury.

Case Description

I saw this injury myself many years ago. I was called to the ICU to evaluate a patient for postoperative tongue pain. The patient was an otherwise healthy 41 year old who had undergone cervical spine decompression for tumor two days before. The patient had been in the prone, head flexed position in tongs during a surgery that had lasted about 7 hours. About 2 liters of crystalloid had been given and blood loss was less than 200 ml. Surgery had been successful and the patient had been extubated at the end of the case neurologically intact.

When the patient started talking to me, speech was terribly slurred. Almost the entire right side of the tongue was a pale brown and gray color, firm, and markedly edematous with an ulceration. Tongue necrosis was diagnosed. I don’t have a picture for this patient, but this photo, taken from an excellent review of tongue necrosis, is similar.

Photo of tongue necrosis from Laryngoscope. 2010 July; 120(7): 1345–1349.

Photo of tongue necrosis from Laryngoscope. 2010 July; 120(7): 1345–1349.

During the case, since neurostimulation was to be used to monitor spinal cord function, two fairly large, soft bite blocks made of rolled gauze had been placed to prevent the patient from chewing the tongue or mouth when stimulated. At the end of the case, the anesthesia team noted that the tongue looked a little swollen and that the tube had left an imprint over the back of the tongue. Continue reading

Plastic In the Airway: An Unsuspected Aspiration Hazard

I saw a potential aspiration hazard in the OR today. How many times a day do we routinely peel plastic wrappers off of airway equipment? If I’m at the surgicenter, I might need 7 face masks, a variety of LMAs and endotracheal tubes and an oral airway or two.

Take a look at the typical plastic wrapped mask here in this photo. We unwrap these sorts of objects dozens of times a day.

photo of Typical plastic wrapped disposable mask

Typical plastic wrapped disposable mask.

Here is the same mask unwrapped. Do you see the hazard I found?

photo of Same unwrapped mask with an almost invisible hazard

Same unwrapped mask with an almost invisible aspiration hazard inside.

Here it is, a tiny piece of torn plastic that was stuck to the inside of the mask. It’s almost invisible unless you look for it.

Photo of an aspiration hazard: a bit of plastic wrap stuck inside the mask

Aspiration hazard: a bit of plastic wrap stuck inside the mask

Look back at the wrapped mask. Do you see it now?

Arrow points at aspiration hazard inside the mask

Arrow points at aspiration hazard inside the mask

Aspirating something like this could have serious consequences. In anesthesia, or any field of medicine, the devil is in the details. You cannot be too compulsive about safety. Check and recheck everything. Every little bit counts.

May The Force Be With You

Christine Whitten MD

 

Cardiac Arrest In The OR

My hospital routinely runs mock codes in a variety of settings to make sure that all providers can quickly and efficiently act as a team if the worst happens. This includes our operating rooms. Cardiac arrest under anesthesia in the OR is fortunately rare.  The total number of OR procedures performed in the US last year was 51.4 million. The incidence of intraoperative cardiac arrest has been quoted as less than 0.1%. However, a small percentage of a large number is still a fairly significant number. Getting prepared for rare events is often more challenging than preparing for regular events. When a rare event happens the shock and fear induced by the event can erase protocol from the most prepared mind. Let me share some of the things that I’ve learned over almost 36 years of OR emergencies. Continue reading