Children younger than 5 have a much higher risk of developing pediatric respiratory failure. Article discusses why a higher risk of hypoxia, an immature cardiovascular system, and inefficient mechanics of breathing increases risk of respiratory failure. #FOAMED #anesthesi Read More …
P/F ratio and associated respiratory physiology explained in easy terms. How to use P/F to estimate the severity of hypoxemia and trend progression of respiratory failure in COVID-19/ARDS — even if formal blood gas determination is not readily available. #FOAMED Read More …
In many ways pediatric anatomy and physiology predisposes a child to respiratory distress and respiratory failure. Inefficient mechanics of breathing is one major risk factor for infants and young children. This article discusses the ways the anatomy of a child creates inefficient mechanics of breathing and predisposes to respiratory distress and failure. Read More …
We routinely use ETCO2 to provide information on ventilation. But ETCO2 can also provide valuable information on the adequacy of cardiac perfusion. It can be an essential tool in ensuring optimal, high quality chest compressions during cardiac resuscitation. Read More …
Conscious sedation can alter respiration, which can lead to the vicious cycle of hypoventilation, hypercarbia, and hypoxia. If you don’t recognize inadequate respiration —and treat it— the patient can suffer injury or die. This article discusses the continuum of sedation and its effect on consciousness and respiration. Read More …
Tension pneumothorax is a life-threatening emergency. This article discusses several iatrogenic bilateral tension pneumothoraces occurring during intubation and emergency airway management. Read More …
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 Read More …
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. Read More …
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. 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. My sincere wish is that this new book helps in the care of our littlest patients, no matter where they are. Read More …
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. This is a case of respiratory failure caused by hypovolemic shock and hypoglycemia in a child. Read More …
When I’m teaching airway management to my Perioperative/OR nurses, I often recount the story of management of a young child’s postoperative respiratory depression. In addition to illustrating the importance of evaluating ventilation in addition to oxygenation, this case shows how good communication makes management of a critical event more effective. Read More …
Ventilating 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 discusses the difference in the use of a self-filling ventilation bag and a free-flow ventilation bag. Read More …
There are 2 types of mismatch: dead space and shunt. Alveolar gas exchange depends not only on ventilation of the alveoli but also on circulation of blood through the alveolar capillaries. 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. Read More …
Breathing room air, oxygen saturation drops precipitously to below 90% within about a minute of the start of apnea in the average healthy adult. While preoxygenation is one of the most important safety measures we can use prior to induction of anesthesia and in preparation for intubation, apneic oxygenation can allow even more time for intubation to occur. Apneic oxygenation using nasal cannula can significantly delay the onset of critical hypoxia.
While breathing room air, oxygen saturation drops precipitously to below 90% within about a minute of the start of apnea in the average healthy adult. One of the most important safety measures we use in anesthesia is to preoxygenate our patients prior to induction of anesthesia and in preparation for intubation. This is especially true if we are planning a rapid sequence induction. Adequate preoxygenation can more than double the time to hypoxia during apnea, allowing more time for intubation to occur.
Preoxygenation increases the margin for safety. It treats any pre-existing hypoxemia in the critically ill patient. It also postpones the onset of hypoxia while the patient is apneic during the intubation attempt. This becomes especially important if the intubation attempt becomes difficult and prolonged.
Speed of onset of hypoxia with apnea depends on metabolic rate and on the actual amount of oxygen available in the patient’s functional residual capacity. To see how preoxygenation can effect this let’s review some physiology. Read More …
As an anesthesiologist, I often run to emergencies where the patient is not breathing adequately and requires intubation. However, before any intubation, a patient in respiratory distress/failure needs ventilation. Providers who have passed ACLS are often able to ventilate an apneic patient well because they have practiced on the manikin.
Providers who infrequently need to ventilate an apneic patient will have more difficulty assisting the ventilation of a patient who is still breathing spontaneously. In addition, providers will occasionally hesitate to try to assist a patient’s breathing while waiting for the intubation team because they feel they don’t know how. Delay in improving ventilation can place your patient at higher risk of complication. This is unfortunate because in many ways assisting ventilation is even easier than manually ventilating an apneic patient. This article reviews the mechanic of breathing to show how to assist ventilation. Read More …
There is often a great deal of confusion about how to manage the care of a patient with COPD because of concern about inducing CO2 retention. This fear of causing CO2 retention sometimes causes providers to withhold or withdraw oxygen inappropriately. Understanding some of the respiratory physiology behind CO2 retention will allow you to make more informed decisions. This discussion will explain why withholding or withdrawing oxygen from a sick CO2 retainer may, or may not, be the wrong thing to do. Read More …
Many people confuse the important distinction between arterial partial pressure of oxygen (PaO2) and oxygen saturation (O2 sat). This is such a key concept that we all must take pains to ensure our staff understands how to use pulse oximetry to identify hypoxemia and hypoxia.
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I often find that my students sometimes confuse oxygenation and ventilation as the same process. In reality they are really very different. Ventilation exchanges air between the lungs and the atmosphere so that oxygen can be absorbed and carbon dioxide can be eliminated. Oxygenation is simply the addition of oxygen to the body.Why do we need to understand this? Let’s look at some common examples. Along the way we will painlessly use the Alveolar Gas Equation to explain two common scenarios:
how hypoventilation causes hypoxia,
why abruptly taking all supplemental oxygen away from a carbon dioxide retainer will hurt them. Read More …