Altered Mental Status: Current Evidence-Based Recommendations for Prehospital Care

Ashley Sanello, MD; Marianne Gausche-Hill, MD; William Mulkerin, MD; Karl A. Sporer, MD; John F. Brown, MD; Kristi L. Koenig, MD; Eric M. Rudnick, MD; Angelo A. Salvucci, MD; Gregory H. Gilbert, MD


Western J Emerg Med. 2018;19(3):527-541. 

In This Article

Abstract and Introduction


Introduction: In the United States emergency medical services (EMS) protocols vary widely across jurisdictions. We sought to develop evidence-based recommendations for the prehospital evaluation and treatment of a patient with an acute change in mental status and to compare these recommendations against the current protocols used by the 33 EMS agencies in the State of California.

Methods: We performed a literature review of the current evidence in the prehospital treatment of a patient with altered mental status (AMS) and augmented this review with guidelines from various national and international societies to create our evidence-based recommendations. We then compared the AMS protocols of each of the 33 EMS agencies for consistency with these recommendations. The specific protocol components that we analyzed were patient assessment, point-of-care tests, supplemental oxygen, use of standardized scoring, evaluating for causes of AMS, blood glucose evaluation, toxicological treatment, and pediatric evaluation and management.

Results: Protocols across 33 EMS agencies in California varied widely. All protocols call for a blood glucose check, 21 (64%) suggest treating adults at <60mg/dL, and half allow for the use of dextrose 10%. All the protocols recommend naloxone for signs of opioid overdose, but only 13 (39%) give specific parameters. Half the agencies (52%) recommend considering other toxicological causes of AMS, often by using the mnemonic AEIOU TIPS. Eight (24%) recommend a 12-lead electrocardiogram; others simply suggest cardiac monitoring. Fourteen (42%) advise supplemental oxygen as needed; only seven (21%) give specific parameters. In terms of considering various etiologies of AMS, 25 (76%) give instructions to consider trauma, 20 (61%) to consider stroke, and 18 (55%) to consider seizure. Twenty-three (70%) of the agencies have separate pediatric AMS protocols; others include pediatric considerations within the adult protocol.

Conclusion: Protocols for patients with AMS vary widely across the State of California. The evidence-based recommendations that we present for the prehospital diagnosis and treatment of this condition may be useful for EMS medical directors tasked with creating and revising these protocols.


Altered mental status (AMS) represents a broad spectrum of disease processes, making treatment modalities equally broad and varied. If the cause for AMS is found, the prehospital care providers will then transition to that more-specific protocol. However, emergency medical service (EMS) providers have limited time to evaluate these undifferentiated patients. Therefore, guidelines for assessment and initial treatment prior to arriving at an emergency department (ED) are essential. The prevalence of AMS in the prehospital care setting is not well known given the limited research in this area. One California county found 27% of all EMS patients had an abnormal Glasgow Coma Scale (GCS).[1] ED data report AMS at a prevalence between 1–10% of visits.[2–4] Prehospital protocols and treatment recommendations for AMS vary widely across the U.S.[5] We provide a summary of available evidence for prehospital assessment and treatment of patients with undifferentiated AMS and additionally evaluate consistency across California protocols.