Techniques in EMS Airway Management

THE CLINICAL CHALLENGE

Airway management in the prehospital environment is fraught with challenges. Many of these same challenges may be encountered when airway management is required in nontraditional locations within the hospital. This chapter focuses on unique management techniques and variations of traditional techniques designed to overcome these challenges.

Location and Environmental Factors

When possible, patients should be moved to a secure, private, warm, well-lit, and spacious environment prior to airway management. This might be best achieved simply by moving a patient in cardiac arrest from a small bathroom to the living room, or might require moving a patient from the roadside into the back of an ambulance. Certain scenarios may require management of the patient in situ: if they are entrapped, if the need for airway management is immediate, if there is no more optimal place close by, or if it is otherwise unsafe to attempt movement. In these circumstances, rescuers should limit airway procedures to only those that are absolutely necessary; this may include only basic airway management until care can be rendered safely.

Patient Positioning for Airway Management

Proper patient positioning can often be exceedingly challenging in the prehospital setting. Prehospital patients are frequently found on the floor, recumbent on soft surfaces, or entrapped. These unique positions may make it difficult to obtain optimal positioning for preoxygenation and airway interventions. Providers often handicap themselves by trying to manage the patient in the position in which they are found rather than taking a brief period to achieve better positioning, which can be beneficial for the provider and patient.

Whenever possible, patients found on the floor or other suboptimal position should be moved to a stretcher before airway management (Fig. 29-1). This practice has the advantage of improving airway management and avoids having to move the patient onto the stretcher while intubated, which could result in tube dislodgement. For patients with cardiac arrest, it may not be feasible or desirable to place the patient on the stretcher. In such cases, towels may be placed behind the head to achieve the classic sniffing position; towels may also be improvised with a small piece of emergency medical services (EMS) equipment or patient belongings (Fig. 29-2). Even more challenging is trying to create a ramped position for an obese patient on the ground, because this requires more padding and can interfere with chest compressions. Ideally, the obese, supine patient without cardiac arrest should be moved to the stretcher and positioned as shown in Figure 29-3.

• FIGURE 29-1. Placing the patient on the EMS stretcher and lifting it up allows for intubation to occur at an optimal height.

For the obese, supine patient with cardiac arrest, the best possible sniffing position should be achieved while continuing chest compressions. If these maneuvers do not create an adequate laryngoscopic view, ventilation should be attempted via an extraglottic device (EGD). If the patient cannot be adequately ventilated with an EGD, two providers can replicate a ramped position by grasping the patient’s outstretched arms from the front and pulling them into position (Fig. 29-4). This procedure should only be maintained for a few seconds, but because cardiopulmonary resuscitation (CPR) must be interrupted in order to perform the maneuver, longer periods are not recommended.

Bag-Mask Ventilation

Although bag-mask ventilation (BMV) is a fundamental airway skill taught to EMS providers at all levels starting at the Emergency Medical Responder level, it can be very difficult to perform in the prehospital setting for a variety of complex reasons. Patients often present with multiple predictors of difficulty based on the ROMAN mnemonic (see Chapter 2), access and positioning may not be optimal, personnel may be limited, and, perhaps most importantly, the procedure is often relegated to the least-experienced provider. Strategies to mitigate these issues include emphasizing optimal technique (proper positioning, use of appropriate airway adjuncts, using two-person and two-handed technique), use of a transport ventilator to free up hands, and assigning a senior person to perform or supervise this critical skill (Fig. 29-5).

• FIGURE 29-2. Achieving sniffing position with improvised supplies, in this case firefighter bunker gear and IV bags.

• FIGURE 29-3. Achieving a ramped position for an obese patient using a combination of padding and elevation of the head of the stretcher.

When difficulty is encountered with achieving an adequate mask seal, early consideration should be given to bypassing these anatomic difficulties with an EGD. EMS providers who are forced to provide one-person BMV without benefit of a ventilator might also consider use of the NuMask, which may be helpful.

Noninvasive Positive Pressure Ventilation

One of the most significant advances in EMS over the last decade has been the widespread adoption of Noninvasive Positive Pressure Ventilation (NIPPV), typically continuous positive airway pressure (CPAP); in some jurisdictions, CPAP has been extended to the Emergency Medical Technician (EMT) level. Numerous products are now available to provide CPAP in the prehospital setting, from simple single-use devices to complex ventilators. In systems without medication-facilitated airway management (MFAM), CPAP is most commonly used as a bridge to facilitate transport to the hospital, because the only other options in the conscious yet distressed hypoxemic patient are either blind nasotracheal intubation (BNTI) or assisted respirations with BMV, both of which are often poorly tolerated. In MFAM systems, CPAP is also used as a preoxygenation strategy and as an alternative to intubation in patients where intubation is predicted to be difficult, where the need for positive pressure respiratory support is predicted to be short, or in those patients in need of ventilatory support but with a “Do Not Intubate” order. Interestingly, despite our own positive anecdotes, the evidence behind prehospital CPAP is mixed (see Chapter 31).

• FIGURE 29-4. Assistants lifting a patient’s arms to demonstrate how to quickly and briefly position an obese patient lying on the ground for intubation without having to build a ramp.