Altered Mental Status of Unknown Cause

Case Study

The bedside nurse initiated a rapid response event for a patient for acute change in his mental status. The patient’s roommate called the nursing staff because he heard the patient thrashing around in his bed for approximately 1 min. Upon the arrival of the rapid response team, the patient’s nurse reported that the patient is a 19-year-old male with a history of asthma admitted to the orthopedic trauma service for bilateral ankle fractures sustained in a motor vehicle accident (MVA) awaiting operative management. The bedside nurse reported that the patient was on continuous vitals monitoring and had a brief oxygen desaturation into the mid-’80 s that resolved spontaneously before the rapid response team’s arrival. The nurse also stated that the patient is usually alert and orientated but confused about the events that brought him into the hospital and is very pleasant and conversant. He has been working with physical therapy and has been able to use a wheelchair without difficulty.

Vital Signs

  • Temperature: 98.3 °F, axillary

  • Blood Pressure: 118/68 mmHg

  • Heart Rate: 68 beats per min (bpm) – normal sinus rhythm on telemetry

  • Respiratory Rate: 15 breaths per min

  • Pulse Oximetry: 99% saturation on room air

Focused Physical Examination

The patient was a well-developed young adult male lying in his bed who appeared drowsy. He was unable to answer any questions or follow commands. There was a sutured laceration above his left eyebrow with surrounding ecchymosis and significant swelling. There were blood-tinged oral secretions around his lips, but there was no obvious tongue or oral laceration. His pupils were equal in size and reactive to light. His pulmonary and cardiovascular exam was unrevealing. His abdomen was soft and non-tender without any peritoneal signs. He had sugar tong splits to his bilateral lower extremities with soft calf and thigh compartments. Motor testing was unable to be performed. There were no signs of any urinary or bowel incontinence.


A cardiac monitor was attached. His airway, breathing, and circulation status were assessed and were stable. Given his acute change in mental status, a stat computed tomography (CT) head was ordered to evaluate any possible intracranial pathologic condition, especially since the patient was involved in a significant MVA. A complete blood count (CBC) was ordered to evaluate for a potential infectious process causing the acute mental change. A basic metabolic panel and a magnesium level were ordered to evaluate for any electrolyte abnormality as the cause of the altered mental status (AMS). Prolactin and lactate were ordered to rule out a recent seizure episode. Bedside fingerstick glucose was 82 mg/dL. During the rapid response, the patient was not given any benzodiazepines or other anti-epileptics. The rapid response team followed up on the results, and imaging was unchanged from the previous trauma scans ordered in the emergency room. There were no electrolyte abnormalities. There was mild leukocytosis, and the prolactin and lactate were elevated. Neurology consultation was requested for the need for anti-epileptics and a formal electroencephalogram (EEG) exam.

Final Diagnosis

Suspected postictal state from a post-traumatic seizure.

Altered Mental Status

A variety of causes can result in AMS. The underlying cause could either be a primary intracranial pathologic condition such as a tumor or seizure or a systemic cause such as overwhelming sepsis, metabolic, or hormonal derangements. Medications, toxins, and illegal substances of abuse can also induce mental status changes. Strokes and other vascular system disorders and psychogenic causes could also be the culprit ( Fig. 34.1 , Tables 34.1 and 34.2 ). Often a combination of any of these broad categories could be at play. During a rapid response, we must quickly and effectively come to the heart of the issue to properly treat the patient.

Fig. 34.1

Common causes of altered mental status.

Table 34.1

Life-threatening causes of altered mentation

Cardiac Acute coronary syndrome, including myocardial infarction, congestive heart failure, dysrhythmias
Endocrine Addison disease, Cushing syndrome, diabetic ketoacidosis, hyperosmolar hyperglycemic syndrome, myxedema coma, thyroid storm
Environmental Heatstroke/exhaustion, hypothermia, high altitude cerebral edema
Infectious Encephalitis/meningitis, pneumonia, sepsis/septic shock, urinary tract infection
Metabolic Hypercalcemia, hypo-/hyperglycemia, hypo-/hypernatremia, metabolic acidosis
Neurologic Acute stroke, concussion, epidural hematoma, non-convulsive status epilepticus, postictal state, subarachnoid hemorrhage, subdural hematoma
Respiratory Hypercarbia, hypoxia
Toxicological Alcohol/illicit drug intoxication/withdrawal, medication overdose, polypharmacy

Only gold members can continue reading. Log In or Register to continue

Nov 19, 2022 | Posted by in CRITICAL CARE | Comments Off on Altered Mental Status of Unknown Cause

Full access? Get Clinical Tree

Get Clinical Tree app for offline access