Airway Clearance Using Suction Devices in Prehospital Combat Casualty Care: A Systematic Review

Rapid Sequence Intubation Using the SEADUC Manual Suction Unit in a Contaminated Airway

The case presented here highlights the utility/feasibility of the SEADUC (EM Innovations, Galloway, OH) manual suction unit in clearing a contaminated airway during rapid sequence intubation. The case also highlights the importance of intubation in a patient with declining mental status in the prehospital environment. A 75-year-old woman suffered a head injury, and a helicopter emergency medical service team staffed with a physician and nurse was tasked with retrieval and transfer back to the tertiary care center. As the flight team rendezvoused with ground emergency medical services and the patient, a decision to intubate was made because of the patient's declining mental status and inability to protect her own airway. While in preparation for intubation, it was noted that the ambulance's electrical suction system was not working, and the flight crew had to resort to a SEADUC manual suction unit to clear the patient's airway of contaminants. The patient's airway was cleared, and she was successfully intubated and transported to a tertiary care center where the patient underwent an emergent neurosurgery procedure/decompression and was discharged home a few weeks later.

The Difficult Airway Redefined

There is no all-encompassing or universally accepted definition of the difficult airway, and it has traditionally been approached as a problem chiefly rooted in anesthesiology. However, with airway obstruction reported as the second leading cause of mortality on the battlefield and first-pass success (FPS) rates for out-of-hospital endotracheal intubation (ETI) as low as 46.4%, the need to better understand the difficult airway in the context of the prehospital setting is clear. In this review, we seek to redefine the concept of the “difficult airway” so that future research can target solutions better tailored for prehospital, and more specifically, combat casualty care. Contrasting the most common definitions, which narrow the scope of practice to physicians and a handful of interventions, we propose that the difficult airway is simply one that cannot be quickly obtained. This implies that it is a situation arrived at through a multitude of factors, namely the Patient, Operator, Setting, and Technology (POST), but also more importantly, the interplay between these elements. Using this amended definition and approach to the difficult to manage airway, we outline a target-specific approach to new research questions rooted in this system-based approach to better address the difficult airway in the prehospital and combat casualty care settings.

A Market Review of Available Airway Suction Technology

INTRODUCTION

Airway injuries are the second leading cause of potentially survivable battlefield death and often require airway management strategies. Airway suction, the act of using negative pressure in a patient's upper airway, removes debris that can prevent respiration, decreases possible aspiration risks, and allows clearer viewing of the airway for intubation. The most important characteristics for a portable airway suction device for prehospital combat care are portability, strong suction, and ease of use.

METHODS

This market review searched academic papers, military publications, Google searches, and Amazon to identify devices. The search included specific characteristics that would increase the likelihood that the devices would be suitable for battlefield use including weight, size, battery life, noise emission, canister size, tubing, and suction power.

RESULTS

Sixty portable airway suction devices were resulted, 31 of which met inclusion criteria - 11 manually powered devices and 20 battery-operated devices. One type of manual suction pump was a bag-like design with a squeezable suction pump that was extremely lightweight but had limited suction capabilities (vacuum pressure of 100mmHg). Another type of manual suction pump had a trigger-like design which is pulled back to create suction with a firm collection canister that had increased suction capabilities (vacuum pressures of 188-600mmHg), though still less than the battery operated, and was slightly heavier (0.23-0.458kg). Battery-operated devices had increased suction capabilities and were easier to use, but they were larger and weighed more (1.18-11.0kg).

CONCLUSION

Future research should work to lighten and debulk battery-operated suction devices with high suction performance.

Portable Medical Suction and Aspirator Devices: Are the Design and Performance Standards Relevant?

Airway clearance refers to the clearing of any airway blockage caused due to foreign objects such as mud, gravel, and biomaterials such as blood, vomit, or teeth fragments using the technology of choice, portable suction devices. Currently available devices are either too heavy and bulky to be carried, or insufficiently powered to be useful despite being in accordance with the ISO 10079-1 standards. When applied to portable suction, the design and testing standards lack clinical relevancy, which is evidenced by how available portable suction devices are sparingly used in pre-hospital situations. Lack of clinical relevancy despite being in accordance with design/manufacturing standards arise due to little if any collaboration between those developing clinical standards and the bodies that maintain design and manufacturing standards. An updated set of standards is required that accurately reflects evidence-based requirements and specifications, which should promote valid, rational, and relevant engineering designs and manufacturing standards in consideration of the unique scenarios facing prehospital casualty care. This paper aims to critically review the existing standards for portable suction devices and propose modifications based on the evidence and requirements, especially for civilian prehospital and combat casualty care situations.