Cautions and caveats for airway management in critical care settings

To the Editor:

Upon review of the article on rapid sequence intubation (RSI) (“The importance of staying current on rapid sequence intubation,” published in August 2010), a number of important omissions caught my attention. I seek to address these not to disparage Mr. Light, but to inform physician assistants who practice in hospital-based settings and to provide a word of caution with regards to RSI and airway management on the whole. RSI is an isolated procedure within the discipline of airway management and must be considered contextually.

Although intubation may be performed by physician assistants, the PA performing this procedure should be both familiar and competent with it. In addition, clinicians who regularly intubate patients must know what to do when intubation fails, up to and including cricothyroidotomy. However, in order to provide safe, quality care, PAs should only perform those procedures that are maintained on their medical staff privileges. To do otherwise puts the PA at a legal risk, even in extreme circumstances, such as when failing to perform such a procedure might mean the imminent demise of the patient.

ACLS (advanced cardiovascular life support) certification has in the past served as a sort of surrogate for instruction on RSI. However, as of 2008, the American Heart Association has de-emphasized the role of RSI in emergency cardiac care; and it has moved its position to support of compression-only resuscitation (COR) if an airway cannot be secured. The primary events excluded from COR include drowning and drug intoxication.¹ Moreover, I felt that the article perpetuated several misconceptions.

• The first may be noted in the Key Points section. As a PA who has worked in critical care for 10 years, I have never been left alone to care for a critically ill patient. Critical care, by definition, is a team sport with players consisting of respiratory therapists, nurses, physicians, and other allied health professionals. Physician assistants, by definition, are collaborative clinicians and should effectively leverage their position on the health care team to provide quality patient care.

• Common quantitative indications for RSI are not discussed: respiratory rate, >35 breaths per minute; hypercapnea with a Pco₂ >55 mm Hg; Pao₂, <60, with Fio₂ of 50% or greater; or signs such as retractions, nasal flaring, etc.²

• One of the most important pretreatments (oxygen) was not addressed in the body of the text; it was only mentioned in Table 1, which is drawn from Wall's Emergency Airway Management. Clinicians need to be aware that they may preoxygenate patients with a bag-valve mask (BVM) indefinitely pending a definitive airway. Paradoxically, patients with coexisting neurologic injuries may be easier to preoxygenate if they have depressed mentation, as they do not actively resist BVM efforts. Also, Wall's recommendation for 3 minutes of preoxygenation has been supplanted by a recommendation for 5 minutes in patients with conditions that may decrease functional residual capacity like pulmonary contusion, rib fractures, hemothorax, or pneumothorax.

• Airway adjuncts (oral airways, nasal trumpets, combitubes, or laryngeal mask airways), which are commonly utilized in prehospital and emergency medicine settings, were not discussed. These adjuncts, as well as others such as noninvasive ventilation (CPAP/BiPAP), have a well-defined role in airway management and should be considered in the clinician's decision-making process prior to RSI.

• The techniques for assessing tube placement were not addressed, including standards of care such as postintubation chest radiography and the interpretation of end tidal co₂ detectors.

• Although pharmacologic paralysis is an important adjunct in airway management, one cannot reasonably maintain that it is first-line management in performing RSI. In my direct experience, I rarely see patients paralyzed for practical reasons. In the critical care environment, we commonly see the combination of an opioid (ie, fentanyl) and sedative (ie, versed). This is due largely to the resources available. Placing a paralyzed patient on a ventilator in the emergency department is difficult. Also, patients who are intubated on the hospital wards would need to be manually ventilated with a BVM until an ICU bed becomes available. The decision to administer a medication that functionally eradicates spontaneous ventilation should not be taken lightly. Several studies in the anesthesia literature purport that pharmacologic paralysis actually increases aspiration risk.³

Ryan O'Gowan, PA-C, FAPACVS
Program Director, Physician Assistant Residency in Critical Care
Staff Physician Assistant, SICU & Neuro/Trauma ICU
Department of Critical Care Operations
UMass Memorial Healthcare
Worcester, Massachusetts

REFERENCES

1. Sayre MR, Berg RA, Cave DM, et al; American Heart Association Emergency Cardiovascular Care Committee. Hands-only (compression-only) cardiopulmonary resuscitation: a call to action for bystander response to adults who experience out-of-hospital sudden cardiac arrest: a science advisory for the public from the American Heart Association Emergency Cardiovascular Care Committee. Circulation. 2008;117(16):2162-2167.

2. Kollef MH, Bedient TJ, Isakow W, Witt CA, eds. The Washington Manual of Critical Care. 1st ed. Philadelphia, PA: Lippincott Williams & Wilkins; 2008:37-54.

3. Eriksson LI. The effects of residual neuromuscular blockade and volatile anesthetics on the control of ventilation. Anesth Analg. 1999;89(1):243-251.

Author's response:

I agree with all of the points Mr O'Gowan mentions in his letter. Airway management is a broad topic, and rapid sequence intubation is just one aspect within that topic. Admittedly, I submitted the article with some trepidation; not for what it contained, but for what it did not. For that reason, I qualified it as a review of recent literature, and I tried to make sure that it would not be seen as instructional in nature. I also did not want rapid sequence intubation to be confused with the much broader topic of airway management in general. Where those efforts fell short, I apologize unreservedly.

Submissions to JAAPA are subject to limitations in length and context. In researching and crafting this article, I elected to cover the aspects of RSI that had recently been studied and written about in the literature. I also felt compelled to include enough of an overview of the procedure that any PA could follow along and get something out of the article. The result is that it does not contain many key aspects of a topic that can, and does, occupy volumes.

It is my hope that more PAs will continue the discussion on all aspects of airway management. If my article has encouraged that at all, then I'll count that as one measure of its success.