to the patient assessment and reformulate a working plan.
Conclusion
Although some may consider patients with undifferentiated conditions difficult or frustrating problems to manage in the prehospital setting, others may find them to be a complex challenge. EMS clinicians must approach such patients with the same degree of consistency they do for other clinical situations, such as trauma or cardiac arrest. Pursuit of medical inquiry coupled with knowledgeable clinical decision making lead to optimal EMS courses of care and successful transitions to subsequent care teams. There is no single model of clinical decision making that adequately relates to the very complex prehospital environment. EMS clinicians should be familiar with tools and techniques they might apply, and the nature of errors they might potentially commit. With this awareness, they might enhance patient care, avoid errors, and improve patient safety.
References
1 1 Mechem C. Emergency medical services. In: Tintinalli J, Ma J, Yealy D, et al., editors. Emergency Medicine: A Comprehensive Study Guide. 9th ed. New York, NY: McGraw‐Hill, 2016. pp. 1–6.
2 2 Clawson JL. Emergency medical dispatch and prioritizing. In: Cone D, O’Connor R, Fowler R, editors. Emergency Medical Services: Clinical Practice and Systems Oversight. Dubuque, IA: Kendall Hunt, 2009. pp. 554–89.
3 3 Clawson JL, Dernocoeur KB, Murray C. Principles of Emergency Medical Dispatch. 5th ed. MPDS Version 13. 0. Indianapolis, IN: Priority Press, 2014.
4 4 Paturas JL. The EMS call. In: Pons PP, Cason D (eds) Paramedic Field Care: A Complaint Based Approach. St Louis, MO: Mosby, 1997. pp. 29–33.
5 5 Atack L, Maher J. Emergency medical and health providers’ perceptions of key issues in prehospital patient safety. Prehosp Emerg Care. 2010; 14:95–102.
6 6 Fairbanks RJ, Crittenden CN, O’Gara KG, et al. Emergency medical services provider perceptions of the nature of adverse events and near misses in out‐of‐hospital care: an ethnographic view. Acad Emerg Med. 2008; 15:633–40.
7 7 Medford‐Davis LN, Singh H, Mahajan P. Diagnostic decision making in the emergency department. Pediatr Clin North Am. 2018; 656: 1097–105.
8 8 Kovacs G, Croskerry P. Clinical decision making: an emergency medicine perspective. Acad Emerg Med. 1999; 6:947–52.
9 9 Ramlakhan S, Qayyum H, Burke D, Brown R. The safety of emergency medicine. Emerg Med J. 2016; 33: 293–9.
10 10 Croskerry P. The importance of cognitive errors in diagnosis and strategies to minimize them. Acad Med. 2003; 78: 775–80.
11 11 Croskerry P. From mindless to mindful practice. N Engl J Med. 2013; 368: 2445–8.
12 12 Kohn LT, Corrigan JM, Donaldson MS (eds). To Err is Human. Washington, DC: Institute of Medicine, National Academy Press, 2000.
13 13 Brennan TA, Leape LL, Laird NM, et al. Incidence of adverse events and negligence in hospitalized patients: results of the Harvard Medical Practice Study. N Engl J Med. 1991; 324:370.
14 14 Thomas EJ, Studdert DM, Burstin HR, et al. Incidence and types of adverse events and negligent care in Utah and Colorado. Med Care. 2000; 38:261.
15 15 Wilson RM, Harrison BT, Gibberd RW, et al. An analysis of the causes of adverse events from the Quality in Australian Health Care Study. Med J Aust. 1999; 170:411.
16 16 Sklar DP, Crandall CS, Loeliger E, Edmunds K, Paul I, Helitzer DL. Unanticipated death after discharge home from the emergency department. Ann Emerg Med. 2007; 49:735–45.
17 17 Robertson JJ, Long B. Suffering in silence: medical error and its impact on health providers. J Emerg Med. 2018; 54: 402–9.
18 18 Jensen JL, Croskerry P, Travers AH. Consensus on paramedic clinical decisions during high‐acuity emergency calls: results of a Canadian Delphi study. CJEM. 2011; 13:310–18.
CHAPTER 15 Altered mental status
Mariecely Luciano‐Feijoó and Jefferson G. Williams
Introduction
The patient presenting with altered mental status (AMS), or altered level of consciousness, is a common encounter for EMS. AMS is not a disease, but rather a possible symptom of many conditions, and the differential diagnosis can be extensive [1]. Many etiologies of AMS have the potential to cause significant morbidity and mortality. It is essential that proper care be initiated in the field, along with early consideration of a broad differential diagnosis. Often, treatment must begin before the etiology of AMS is confirmed. In most instances, this treatment should be instituted in conjunction with attempts to determine the underlying cause. The main challenge of a prehospital patient with undifferentiated AMS is to rapidly identify and treat life‐threatening or potentially reversible problems in the field in order to prevent added morbidity from the complications of a prolonged condition.
Assessing mental status
Altered mental status can be defined as a change in a person’s level of consciousness or cognitive function [2]. Whether these changes occur over time or suddenly, disruption in normal brain function can cause a change in usual behavior that may not be noticeable to the patient (him or herself) but is often noticeable to others and a cause for concern. Friends, family members, or bystanders may then summon EMS.
AMS encompasses a collection of more specific neurologic problems. For example, a patient with AMS may have a change in consciousness, which is described as having two major components: arousal and content. A patient with a change in arousal (level of alertness) may range from unresponsive (comatose) to hyperalert and unable to focus on the examiner. On the other hand, a patient with a change in the content of his consciousness may have a normal level of alertness but may have a change in brain function that causes an inability to interact with his environment (e.g., an inability to interpret or form language) [2].
Assessing mental status is about determining what specific behaviors or actions (or lack thereof) of a patient are abnormal or different from that patient’s usual baseline brain function. The assessment should consider what deficits are present (i.e., alteration in alertness, content, or both) and the timing of those deficits. For example, two common states of altered mental status are delirium and dementia. Delirium is distinguished by its acute onset, and patients may wax and wane in level of arousal, attentiveness, and cognition. Dementia is characterized by a more gradual onset of diminished cognition with normal level of arousal and often decreased orientation.
Assessment of the AMS patient may be challenging due to the breadth of abnormalities that the term encompasses and because the AMS patient is impaired in his or her ability to participate in the history and exam. Common medical terms used to describe AMS, such as stuporous, obtunded, or confused may hold different meaning for different medical professionals. For this reason, they are best avoided. Family or bystanders may also describe vague symptoms, such as “he’s just not acting right,” or nonspecific concerns. Nonetheless, the EMS clinician can develop an effective differential diagnosis and treatment plan by determining a patient’s specific deficits and gaining an understanding of timing and specific possible causes via a thorough history and exam.
Approach to the patient with AMS
Once scene safety
