Anatomic Dead Space Affects Hypoventilation

Understanding anatomic dead space is important to recognizing subtle hypoventilation. Hypoventilation from sedation, pain medications, anesthesia in the immediate postoperative period is common. The most obvious sign is slowing of the rate of breathing. A more subtle sign is that tidal volume becomes shallower. Having a tidal volume close to, or smaller than the patient’s dead space can lead to significant hypercarbia, hypoxia, and respiratory failure. This article discusses the concept of dead space and it’s clinical use in recognizing hypoventilation and preventing hypoxia and hypercarbia. Continue reading

GlideScope Technique For Intubation In Small Mouths

The GlideScope Video Laryngoscope (GVL) is an extremely useful tool for managing challenging intubations, but it can be more difficult to use if your patient has a small mouth and a high arched, narrow palate. The problem: once the GlideScope is in place in a small mouth, maneuvering the endotracheal tube around it and into the posterior pharynx can be challenging. If you can pass the endotracheal tube (ETT) at all, the cuff tends to scrape against the teeth, risking rupture. However, there is a modified GlideScope technique you can use in those situations. Continue reading

Difficult Intubation In A Newborn

Difficult neonatal intubation can occur unexpectedly. We’re ready to perform neonatal resuscitation in the delivery room. We may be less ready to have to deal with a difficult neonatal airway at the same time. Recently I, and my colleagues, had to manage an unanticipated difficult neonatal intubation in labor and delivery.

The Case

The baby was born extremely edematous, and in respiratory distress. Although it was easy to ventilate the baby using the NeoPuff, airway swelling prevented the neonatologist  from identifying the epiglottis and vocal cords. The anatomy was too distorted. Following protocol when faced with a difficult intubation, the neonatologist called a “Code White”, an overhead page that in my hospital summons help from anesthesia, nursing, respiratory care and pharmacy to assist with either a emergency pediatric cardiac arrest or emergency intubation.

As a responding anesthesiologist, I too was unable to see landmarks during laryngoscopy. Continue reading

Announcing My New Book: Pediatric Airway Management: A Step-by-Step Guide

At long last, after two years of writing (and rewriting),  illustrating, and  filming  on-line videos, I’m excited to announce the publication of my new book Pediatric Airway Management: A Step-by-Step Guide, by Christine E. Whitten MD.

Anyone who rarely cares for children tends to be anxious when faced with a small child’s airway. This is true even if they are comfortable with adult airway management.

My goal for this book is to demystify basic pediatric airway management. I want to give you the skills you need to recognize when a child is in trouble and act quickly to safeguard that child, including helping them breathe if necessary. Continue reading

NITROUS OXIDE: SHOULD WE USE IT?

When I was training, we used nitrous oxide on just about every anesthetic. It was easy to use. It was inexpensive. It didn’t tend to effect hemodynamics so it was useful in less stable patients when combined with an opioid. It helped speed induction through the second gas effect. It was not metabolized so renal and liver insufficiency were of less concern.

However, with all of the more recent investigation into reasons for cognitive dysfunction or decline in infants and the elderly following anesthesia, a lot more is now known about the pharmacologic disadvantages of nitrous oxide (1, 2, 3). Continue reading

Intubation During Cardiac Resuscitation

Intubation during cardiac resuscitation is often challenging because of the circumstances surrounding the intubation. Excitement and apprehension accompany this life saving effort. If you don’t intubate often, you’re likely to be nervous. Even experienced intubators get excited in emergency situations, but we control our excitement and let the adrenaline work for us, rather than against us.

Step one, therefore, is to remain in control of your own sense of alarm. The leaders, which includes the person in control of the airway, must stay calm. If you appear panicked, the rest of your team will follow your lead.

Step two is to quickly assess the situation. Is the patient being ventilated? Ventilation takes priority over intubation. Is there suction available? Without suction you many not be able to see the glottis, and you won’t be able to manage emesis. What help do you have? The intubator almost always needs some assistance in having someone hand equipment, or assist with cricoid pressure, among other tasks. As I tell my students, intubation is a team sport.

Finally you need to assess what position the patient is in, and how can you optimize that position. The patient is often in a less than optimal position while chest compressions are in progress. You usually find the patient in one of two awkward positions: on the ground or in a bed. This article discusses techniques to better manage intubation during cardiac resuscitation, especially with the patient in an awkward position. Illustrations are copyright from Anyone Can Intubate, 5th Edition.  Continue reading

When Learning Intubation Is Hard

Learning to intubate is easier for some people than for others. Sometimes, no matter how knowledgeable you are about the theory of the intubation technique, the novice can still struggle to bring it all together to pass the endotracheal tube. The anatomy can be confusing. Understanding how to place the laryngoscope blade and manipulate that anatomy can be challenging. And all the while you must be ever vigilant to protect those precious front teeth, avoid hypertension and tachycardia, and breathe for the patient at regular intervals.

I believe there are 4 chief barriers that inhibit learning how to intubate:

  1. Failure to visualize how the outside anatomy links with the inside anatomy makes it hard to predict how deeply to insert the blade.
  2. A mistaken belief that placing the laryngoscope blade itself is all that is needed to align the axes of the airway and reveal the larynx.
  3. Failure to grasp the dynamic nature of the larynx, and the need to actively manipulate it during intubation.
  4. A lack of understanding that intubation is not a sequence of isolated steps, but is instead a complex dance of interacting steps, each setting the stage for the next.

This discussion is going to assume some knowledge of the basic intubation technique. If you’d like to review those basics you can find links for multiple prior in depth discussions at the end of this article. (Illustrations and animation from Anyone Can Intubate, 5th edition, C Whitten MD.) Continue reading

Not All Airway Emergencies Need Intubation

An emergency department physician I met the other day shared with me an experience from her hospital  that offers a good example of the fact that there are many different ways of managing an airway emergency in a child that don’t involve intubation. Medical management can sometimes avoid some of the risks of losing the airway that intubation might impose.

The Case

The child was an 18 month old girl whose older brother had been playing with laundry detergent pods. He had offered a pod to his little sister, who promptly put it in her mouth and chewed it, releasing the liquid. Her mother had brought her to the emergency room with respiratory distress. The child had severe stridor and was breathing at 40 times a minute. Oxygen saturation was 92%. She was awake and alert but anxious.

The ED doctor recognized significant airway obstruction and was concerned that the obstruction could worsen if the edema got worse. She immediately called for an anesthesiologist and a Head and Neck surgeon to come to the Emergency Department to evaluate the child. While waiting, she gave 10 mg of IM decadron and treated the child with nebulized racemic epinephrine. She attached a pulse oximeter and left the child sitting on her mother’s lap and otherwise did not disturb the child, trying to avoid making her cry. By the time the anesthesiologist and surgeon arrived the stridor, although still present, sounded better.

The question was what to do now? Continue reading

Remember That Respiratory Failure Is Not Always Due to Lung Failure

There are many causes of respiratory failure. Some causes of respiratory failure result from disease or damage to the respiratory system. However disease or injury to other organ systems such as the central nervous system, the musculoskeletal system, or the presence of cardiac or septic shock can also cause respiratory dysfunction.

While final diagnosis will certainly affect treatment, assessing and managing the patient’s ability to breathe will not change with diagnosis.  However, once the airway is secure, you then have to diagnose and treat the real problem in order to resolve the respiratory failure.

The Case

In this case, I was an anesthesia resident doing my pediatric rotation at a children’s hospital. It was my turn to be on call for the weekend. At this particular hospital back in 1982, the anesthesia department managed the airway emergencies in the Emergency Department so when I got the page to go to the ED, I ran.

Inside the triage cubicle a 6 year-old girl was clearly unresponsive. She had been sick with fever, nausea, vomiting and diarrhea for several days according to her mother, who was crying in the corner. She hadn’t been able to hold down any food or fluids for over 24 hours. Her temperature was 102F. She was breathing rapidly but very shallowly. We did not as yet have pulse oximetry, but her color was dusky blue. Her blood pressure was 60/40 and her pulse was 150. She looked septic.

I placed an oral airway and assisted her breathing. She didn’t react at all to the oral airway — no gag reflex. We decided to intubate.

My colleagues quickly placed an IV and I decided to intubate without induction agent or muscle relaxant. If she didn’t need those agents then I didn’t want to potentially compromise her status by giving them. Had she reacted at all when I started to perform direct laryngoscopy I would have aborted and changed the plan.

She didn’t respond at all as I slid the endotracheal tube into the trachea.

We gave her two boluses of 20ml/kg of normal saline. Her color improved, her pulse came down to 110 and her blood pressure rose to 80/50, appropriate for her age. But she still hadn’t woken up.

Ten minutes later the first blood test results returned. Her blood glucose was 10, extremely low. We gave her 2 ml/kg of D25W. Within two minutes she woke up and started fighting the endotracheal tube. As her other vital signs looked much improved and she was now awake and protecting her airway, we elected to extubate her.

The child was admitted to the pediatric ward, was treated for gastroenterits and she did well.

Learnings: Hypovolemia and Hypoglycemia Can Cause Respiratory Failure

This was the first experience that I remember seeing in my career that demonstrated that hypovolemic shock and hypoglycemia can cause profound respiratory failure without lung pathology.  It’s important to remember that respiratory failure can result from a variety of other systemic problems, not just dysfunction of the respiratory system.

Table showing the difference multi-system causes of respiratory distress and respiratory failure

Respiratory distress or respiratory failure can come from many causes.

While assisting ventilation and protecting the airway are first priorities to stabilize a patient, treating the cause of the respiratory failure may require more than just ventilation and/or intubation. In fact, treating the cause can sometimes help you avoid the progression of respiratory distress to respiratory failure. If you don’t consider a potential problem or cause, you’re not going to be able to diagnosis it.

May The Force Be With You

Christine Whitten MD
Author of Anyone Can Intubate: a Step by Step Guide, 5th Edition
and
Pediatric Airway Management: a Step by Step Guide

Button to see inside or buy the book Pediatric Airway Management: A Step-by-Step Guide by Christine Whitten    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

Please click on the covers to preview at amazon,com

 

 

Exhaling During Manual Ventilation Is As Important As Inhaling

Exhalation during manual ventilation is as important as inhalation. One of my readers recently asked a very important question about ventilating a patient with a bag-valve-mask device: “Is there an outlet for the expired air of the patient?” The answer is yes. When ventilating a patient we are concentrating, and rightfully so, on watching the lungs expand and verifying that we hear breath sounds. It is just as important to verify that your patient can exhale. All ventilation devices have a built in pressure relief valve, also called a pop-off valve, which allows you to balance the force needed to expand the lungs with the ability to the patient to passively exhale. Failure to allow exhalation can lead to patient injury from barotrauma.

Illustration showing the parts of a bag-valve-mask device, using a self-filling bag as an example.

Common parts for bag-valve-mask devices, In this case a self-inflating style bag. The reservoir bag, when present, allows near 100% inspired oxygen if allowed to fill.

Continue reading

Communication In A Crisis: A Case of Respiratory Depression In A Child:

When I’m teaching communication in a crisis to my Perioperative/OR nurses, I often recount the story of what happened during one particular child’s recovery years ago. This case, involving a 2 year old child who developed respiratory depression in the recovery room, demonstrates how good communication in a crisis, including the ability to challenge an authority figure, can improve patient safety and allow collaborative teamwork in a crisis management situation. 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

MacGyvering In Anesthesia

I used to love the old TV show MacGyver, which featured an inventive hero who frequently had to improvise some clever device from ordinary objects in order to beat insurmountable odds and save the day.  The concept was so popular that the word MacGyver became a verb. Oxford Dictionaries state that to “MacGyver” is to make or repair something “in an improvised or inventive way, making use of whatever items are at hand”.

As I have traveled the developing world on medical missions I have often had to reinvent ways to do the things I take for granted in my sophisticated operating room, such as reassembling an anesthesia machine that fell apart right after intubation (see this story here) or improvising PEEP from some suction tubing and a bottle of water. (see that story here)

But being able to improvise is just as important in the settings of the more modern hospital. 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

Avoiding Pediatric Drug Errors

Pediatric drug errors are unfortunately common. The literature states that medication errors occur in 5% to 27% of all pediatric medication orders, a very sobering number. Considering that many of these errors occur in the smallest, and therefore most vulnerable, of our little patients, the potential impact is especially great.

For the last 3 months, I’ve been teaching critical event training classes for our OR and Perioperative RNs, Anesthesia MDs and CRNAs, and OR techs in preparation for opening our new hospital in San Diego. Several of the scenarios involved pediatric cases. As part of that process, I’ve been reviewing with my providers ways to avoid the potentially deadly problem of pediatric drug dosing errors as well as ways to avoid them. Let’s discuss some of the ways to make pediatric medication administration safer. Continue reading

Difference in Manual Ventilation: Self-Inflating Ventilation Bag vs. a Free Flow Inflating Bag

Manual ventilation with a bag-valve-mask device requires a good mask seal against the face in order to generate the pressure to inflate the lungs. But it also requires knowledge of how to effectively use the ventilation device to deliver a breath. This article will discuss the differences in ventilation technique for self-inflating vs free-flow ventilation bags. Understanding those differences is important for successful manual ventilation of your patient. Continue reading

Ventilation Perfusion Mismatch

Alveolar gas exchange depends not only on ventilation of the alveoli but also on circulation of blood through the alveolar capillaries. In other words it depends both on ventilation and perfusion. This makes sense. You need both oxygen in the alveoli, and adequate blood flow past alveoli to pick up oxygen, other wise oxygen cannot be delivered. When the proper balance is lost between ventilated alveoli and good blood flow through the lungs, ventilation perfusion mismatch is said to exist.

The ventilation/perfusion ratio is often abbreviated V/Q. V/Q mismatch is common and often effects our patient’s ventilation and oxygenation. There are 2 types of mismatch: dead space and shunt.

Imbalance between perfusion and ventilation is called ventilation perfusion mismatch. This illustration compares shunt, the perfusion of poorly ventilated alveoli; and Physiologic dead space: the ventilation of poor perfused alveoli.

Shunt is perfusion of poorly ventilated alveoli. Physiologic dead space is ventilation of poor perfused alveoli.

This article will describe how dead space is different from shunt. It will help you understand how you can use these concepts to care for your patient. Continue reading