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CHAPTER 14 The challenge of the undifferentiated patient
Andrew Travers
Introduction
The Call‐Taking Process
When a patient calls 9‐1‐1 and speaks with an emergency medical dispatcher, the complex process of providing optimal care has been initiated. This first point of medical contact, the interaction between the patient and telecommunicator, can influence every subsequent experience of patients during their prehospital and even in‐hospital care. Consequently, it is essential for the telecommunicator to initiate and optimize clinician–patient contact for the subsequent emergency medical services (EMS). The EMS clinician, in turn, optimizes contact with the emergency department (ED) or other destination.
Although many consider that the 9‐1‐1 public safety answering point is involved only in resource allocation such as dispatching ambulances, it also has a pivotal role in the provision of patient care [1]. The accurate identification of the chief complaint by the telecommunicator serves as an adjunct to the field personnel by allowing them to incrementally build on the dispatch “diagnosis” and initiate the appropriate therapy. If the telecommunicator incorrectly identifies the chief complaint, this may result in ineffective or inappropriate prehospital therapies, and even worse, it may introduce systematic biases that affect provision of patient care from the EMS clinician–patient contact onward [2, 3].
During the initial steps in the telecommunicator–patient interview, for example, if the chief complaint includes scene safety issues (e.g., drowning or electrocution), the telecommunicator decides on the protocol that best addresses the situation [3]. If the chief complaint involves trauma, the telecommunicator decides on the protocol that best addresses the mechanism of injury (e.g., fall, motor vehicle crash). When the chief complaint appears to be medical in nature, the telecommunicator chooses the protocol that best fits the patient’s foremost symptom, with the priority symptoms taking precedence. Regardless of which call is assessed, the subsequent dispatch information can influence the thought processes of the responding EMS clinicians and potentially influence how they approach the patient [4].In the case of drowning or electrocution calls, for instance, the responders are preparing themselves for the type of call, essentially reviewing in their minds the protocols and procedures to use when approaching the patient. For all calls, the EMS personnel consider their previous experiences to determine how to proceed when they initiate their own first medical contact.
En Route to the Patient
Just as emergency physicians do when they pick up a medical chart, view the chief complaint, and begin their approach to the patient with some element of preconceived notions based on the recorded chief complaint, so do field personnel when they are approaching the patient after being dispatched with some form of information. This can be beneficial in that it may immediately confer some sense that the patient has no high‐priority symptoms, thereby compelling the EMS clinician to delve further into the reason for the EMS call. It can also be detrimental, in that it may mislead the clinician into assuming that no priority symptoms are present when in reality there are one or more. The result may obviously affect the patient, whose problem is potentially minimized or underestimated, and for whom inappropriate or ineffective protocols are applied. This may convey actual risk to the patient if it leads to a negative interaction between EMS clinician and patient, resulting in mistrust and, in some cases, no transport to a hospital [4].
EMS personnel must compile a massive amount of information in a relatively short period. They must incorporate this information with their prehospital clinical skills and baseline knowledge in their clinical decision making, which is necessary to assess and treat patients effectively. Similar to emergency physicians, EMS clinicians become expedient decision makers, using strategies to improve efficiency and thoroughness. They sometimes call on certain rules of thumb, shortcuts, and abbreviated thinking to make fast, efficient, and accurate decisions, or what clinical decision experts term “heuristics” [4]. Various ethnographic and descriptive studies exploring medical errors, adverse events, and near misses in EMS have shown that EMS clinician decision making is a predominant factor influencing patient safety in EMS [5, 6].
When EMS clinicians are interacting with a patient, there is clinical reasoning related to both the line of medical inquiry, such as the history, physical examination, and diagnostic tests, and the clinical decision making (i.e., the cognitive process of using data to evaluate, diagnose, and treat the patient) [8]. Clinical reasoning is a tremendously complex process and is under intense continuing investigation. There is no single model of clinical decision making that adequately relates to the very complex environment that exists in the emergency setting. Rather, there are several models or strategies that individuals use in clinical decision making or cognitive performance including:
pattern recognition or skill‐based (e.g., making a diagnosis immediately on entering the room, which is frequently unconscious, automatic, and based on years of experience)
rule based (e.g., advanced cardiac life support algorithms)
hypothetical