Emergency Medical Services. Группа авторов
have a big effect on airway illumination.
Studies have identified that there is variation in light output among different laryngoscopes. When the light output of curved laryngoscope handles at 19 emergency departments in the Philadelphia area was evaluated, the median luminance varied widely from 11 lux to 5,627 lux (lux is the SI unit of illuminance equal to 1 lumen per square meter) [8]. Factors that may influence illumination brightness include bulbs/laryngoscope type (fiber optic versus regular), condition of batteries, and equipment condition (e.g., multiple sterilizations potentially causing damage to light output).
The influence of laryngoscope illumination grade on time to successful mannequin intubation has been assessed [9]. Intubations were conducted on mannequins with three clinically plausible intensities of light: high (600 lux), medium (200 lux), and low (50 lux). At perceived suboptimal intubation lighting conditions (50 lux), there was no difference in time to intubation on mannequins in this study. Clinicians can see the larynx at very low light levels [10]. The minimal acceptable lighting, depending on bulb type, is anywhere from 9 to 34 lux. The notion is straightforward. Low‐complexity intubations may be possible at very low light conditions, as the airway operator is familiar with anatomy and other visual clues that will lead to a successful intubation. Difficult airways may require increased lighting to identify anatomical landmarks.
If conditions are such that achieving sufficient lighting to facilitate laryngoscopy is not possible, then at least three options exist. Digital intubation may be accomplished using solely tactile feedback. If available, intubation may be achieved using a lighted stylet. Finally, supraglottic airway insertion requires no illumination of the airway (see Chapter 3).
Suboptimal suction manifests as similar visualization challenges. While electric portable suction equipment may be effective, it is subject to breakdown and malfunction for myriad reasons. Manual suction devices may suffice in some situations but not others. In all cases, EMS clinicians should be prepared for circumstances when visualization is suboptimal and have knowledge, abilities, and equipment ready. As with suboptimal illumination, depending on the specific clinical situation, EMS clinicians may employ a gum elastic bougie for tactile feedback and orientation, lighted stylet, or blindly inserted supraglottic airway, or proceed to digital intubation.
Minimizing airway management equipment
The standard prehospital intubation kit contains a range of equipment and may take up considerable space. For example, it might include a laryngoscope handle, multiple blades, multiple sizes of tracheal tubes, stylets, syringes, tape, a capnometer, and spare batteries and bulbs. There are situations in which minimizing the airway management pack might be necessary. For example, a wilderness or tactical mission requires smaller, compact equipment kits [11]. Over the past three decades, there have been major advances in miniaturizing medical devices, offering new options for portability, including, for example, portable versions of continuous quantitative end‐tidal CO2 devices (Figure 4.7), suction devices, and video laryngoscopes.
An example of a condensed airway management kit is shown in Figure 4.8.
Figure 4.7 Small continuous battery‐powered end‐tidal CO2 device.
(Smith Medical BCI Capnocheck)
Figure 4.8 An example of a condensed airway pack with a laryngoscope roll (added ET tube and bougie), supraglottic airway, and a cricothyroidotomy kit. (North American Rescue, King LT, H+H).
Source: North American Rescue, LLC.
It may be possible to select gear with multiple uses. For instance, a 14‐gauge IV catheter may be bent and used as a cricothyroidotomy hook. Along the same lines, one might secure the endotracheal tube with tape rather than a commercial endotracheal tube holder.
Telemedicine‐assisted airway management
Telemedicine has experienced a tremendous amount of development in the past decade. Applications for providing remote care have been seen in many disciplines including maritime, combat, and concierge medicine. Telemedicine may potentially play a role in prehospital airway management.
Sakles et al. described tele‐intubation assistance for remote hospital and prehospital intubations [12]. In their tele‐intubation set up, ambulances were fitted with wireless modules to enable monitoring of intubations at a distance of 500 feet from the ambulance. Rescuers used a modified video laryngoscope capable of transmitting images back to the telemedicine center. Sibert et al. conducted a feasibility study demonstrating remote assistance of intubation [13]. In this project, mannequin intubation footage was transmitted from the back of an ambulance to a physician in a remote monitoring station. A third study by Mosier et al. used readily available smartphone technology to facilitate tele‐intubation [14].
It is important to recognize that while telemedicine may potentially aid airway management decision making, it cannot (yet) replace the actual motor or dexterous actions for airway procedures. The primary benefit of tele‐intubation is to facilitate the airway decision‐making process. For example, a remote advisor may guide the decision to intubate (or not intubate) an apneic victim of a drug overdose. This same remote observer may also coach the rescuer through performance of airway procedures. The development of new and inexpensive transmission devices such as smartphones makes these applications potential realities.
Airway management in the tactical setting
Combat operations in Iraq and Afghanistan have added to our knowledge regarding tactical medicine and tactical airway management [15]. Concurrently, there has been growth in the field of tactical emergency medical support as the current wars have demonstrated the utility of specialized tactical medical care. Events in the United States due to active shooters and bombers have also revealed the need for specialized clinicians in tactical medicine [16, 17].
Providing airway management during combat or tactical operations
Current Tactical Combat Casualty Care (TCCC) guidelines direct medical interventions based on three phases of care: care under fire, tactical field care, and tactical evacuation care [18]. The Tactical Emergency Casualty Care (TECC) guidelines, the civilian equivalent of TCCC, similarly specify three phases: direct threat care, indirect threat care, and evacuation care [19] (see Chapter 107). In both guidelines, the range of potential airway management techniques increases in scope as the threat diminishes. Sophisticated airway interventions are usually not in the best interest of safety for the clinician, the tactical team, or the patient in the highest threat environments. Other than positioning the patient to protect the airway, if feasible, airway procedures are generally deferred to the tactical field care phase of operations.
During tactical field care and indirect threat care stages, the clinician and patient have been able to move to safe cover. Here, more attention can generally be afforded to airway management. Both TCCC and TECC guidelines advocate for simple airway maneuvers in the field, to include chin lift/jaw thrust, nasopharyngeal airway placement, and placement of the casualty in the recovery position for unconscious casualties without airway obstruction. For those