Unconscious Patient - Common Cause and Uncommon Cases and Their Emergency Management

Introduction:

Unconsciousness is the absence of awareness of self and the environment and the inability to respond to external stimulation. When someone becomes unconscious, they are unaware of their surroundings, unresponsive, and unarousable. A temporary or permanent impairment of a network of neurons in the brainstem that controls arousal-sleep-wake transitions occurs in unconsciousness.

A localized problem affecting a part of the brain or a systemic issue involving other vital organs and the entire body can lead to unconsciousness. An unconscious person can have several underlying clinical states and critical illnesses. The causes of unconsciousness can be reversible or permanent. The unconscious patient loses all their protective reflexes and is more prone to injury and aspiration. Some regain consciousness without medical help, while others require emergency medical care, intensive diagnostic testing, and treatment.

What Causes Unconsciousness?

The various causes of unconsciousness are categorized into structural, systemic, and psychiatric causes. The structural causes include those that affect the part of the brain controlling consciousness. These include the following:

• Stroke (due to lack of blood supply to the brain).

• Ischemic (decreased blood and oxygen) brain injury.

• Bleeding in the brain.

• Inflammation (with swelling) in the brain.

• Tumors (cancerous growth).

• Blood clot (blocking major blood vessels of vital organs).

• The fluid build-up in the deep cavities in and around the brain (acute hydrocephalus).

The systemic causes affecting the entire body can also make a person unconscious. These include:

• Low blood sugar (hypoglycemia).

• High blood sugar (hyperglycemia).

• Low sodium levels in the blood (hyponatremia).

• High blood sodium levels (hypernatremia).

• Increased blood calcium levels.

• Seizures.

• Heart emergencies such as heart attacks.

• Sepsis (widespread infection in the body).

• Inflammation of the membranes and fluid around the brain and spinal cord.

• Adrenal crisis (adrenal insufficiency).

• Pituitary hormonal insufficiency.

• Hormonal imbalances and endocrine abnormalities.

• Severely low thyroid hormone levels (myxedema coma).

• Drug and medication overdose.

• Excessive alcohol.

• Antipsychotic agents misuse (neuroleptic malignant syndrome).

• Severe liver disease.

• Build up of toxins in the blood.

• End-stage renal disease.

• Heavy metals and lead poisoning.

• Malaria.

• Invasive fungal infections in the blood.

• Exposure to weed killers (herbicides).

• Toxic inhalation and exposure to gasses such as carbon monoxide.

• Anesthesia (given during surgery to relieve pain and induce loss of awareness).

The psychiatric causes of unconsciousness include the following:

• Catatonia (a type of schizophrenia).

• Severe depression.

• Conversion disorder (symptoms that a medical evaluation cannot explain).

• Malingering.

What Are the Most Common Causes of Unconsciousness?

Among all the causes, the most common causes of unconsciousness include the following:

1. Road traffic accidents.

2. Severe loss of blood.

3. Trauma to the head, brain, or chest.

4. Drug misuse or overdose.

5. Alcohol poisoning.

6. Low blood glucose levels (hypoglycemia).

7. Low blood pressure (hypotension).

8. Fainting or syncope due to lack of blood and oxygen supply to the brain.

9. Seizure.

10. Stroke.

11. Heart emergencies such as irregular heart rhythm and heat.

12. Stress.

13. Dehydration.

14. Hyperventilation (due to quick breathing).

How Is an Unconscious Patient Managed Initially?

The health care professional usually questions the caregiver or the person accompanying the patient regarding the patient’s medical history, as the details help to identify the cause of unconsciousness. A history of chronic diseases of the heart, lungs, and kidneys, intoxications, and medications such as sedatives or psychoactive drugs contribute to prompt diagnosis and treatment. An unconscious person does not respond to stimuli, lacks gag reflex or pupillary response, and may require immediate airway and breathing assistance. The emergency personnel quickly assesses the unconscious patient and performs a prompt physical examination. The patient’s pulse, airway, and breathing pattern are examined first. Basic life and advanced cardiovascular support (heart care) are initiated if the patient has no pulse or breathing problems. The various steps involved in advanced life support include:

1. Cardiopulmonary resuscitation is initiated immediately. Fast and hard compressions (about two inches deep) are done in the center of the chest at the rate of 100 to 120 chest compressions per minute (30 compressions every 15 seconds). The chest can recover fully after each compression without losing hand contact with the patient’s chest. Interruptions in the chest compressions are kept at a minimum.

2. Oxygen is supplied.

3. A monitor or defibrillator is attached to check the heart rhythms.

4. If the heart rhythm is shockable, shock is delivered using a defibrillator.

5. The cardiopulmonary resuscitation is repeated for another two minutes.

6. A needle is inserted to obtain intravenous access (into the veins) or intraosseous access (into the bone) to administer emergency medications.

7. If the heart rhythm is still shockable, a second shock is delivered using a defibrillator.

8. Next, cardiopulmonary resuscitation is repeated for two minutes. Epinephrine (one milligram every three to five minutes through the vein or bone) is administered to restore blood flow.

9. Advanced airway management (to ensure proper breathing) and monitoring of carbon dioxide levels in the exhaled breath are considered depending on the patient's condition.

10. Airway management includes:

    1. Bag-mask ventilation (oxygen is pumped through a bag attached to the mask). The chest compression-to-ventilation ratio of 30:2 is used.

    2. Tubes (such as endotracheal tubes) are inserted into the windpipe, and oxygen is supplied to the lungs.

    3. Noninvasive positive pressure ventilation (mild air is blown into the airway through tubes or masks to keep it open).

11. Suppose the patient’s heart rhythm remains shockable. In that case, a third shock is delivered, and cardiopulmonary resuscitation is done for another two minutes, after which drugs such as Amiodarone or Lidocaine are administered.

12. In the case of cardiac arrests, the reversible causes are treated.

13. If the patient responds, they show signs of the return of spontaneous circulation (ROSC), such as improvement in pulse and blood pressure and return of normal waves in the heart monitor.

14. If the patient has non-shockable heart rhythms, cardiopulmonary resuscitation must be performed immediately with rhythm analysis every two minutes. This is continued till we attain an organized heart rhythm. The pulse is then checked every two minutes of chest compressions. Quality cardiopulmonary resuscitation is continued till a pulse is attained. Drugs such as Epinephrine to increase blood flow to the heart and brain are administered, and airway management interventions and treatment of the reversible causes are initiated to improve the chance of the return to spontaneous circulation (normal blood flow).

15. Once the patient is stabilized, a neurological assessment is performed to assess and treat unconsciousness.

How Is the Unconsciousness of the Patient Determined?

After initial resuscitation and if the patients have normal pulse and breathing patterns, a neurological examination is done to determine any neurological lesions. Extreme blood loss, brain damage, and organ failure can cause reduced brain function and coma. Clinical scaling systems or coma scales assess the patient’s consciousness during emergencies. This help analyzes the neurological status of severely ill or injured patients with head or brain injury and damage. A reliable scoring method is used to get a clear and communicable portrayal of the patient’s consciousness level, assessing the three key aspects of responsiveness - the patient’s eye-opening, motor, and verbal responses. The following neurological assessments are commonly used to assess the consciousness or responsiveness of emergency room patients:

1. Glasgow Coma Scale (GCS).

2. A full outline of unresponsiveness (FOUR) score.

3. Assessment of pupils.

What Is the Treatment for Unconsciousness in Patients?

As the cause of the unconsciousness is initially unknown, initial management paradigms occur before a definitive diagnosis or complete evaluation. The initial treatment and care of unconscious patients are based on the following principles:

1. Ensuring sufficient oxygenation (oxygen supply to all vital organs, including the brain).

2. Maintaining blood flow and circulation (treating heart and lung-related problems).

3. Controlling the blood glucose levels.

4. To check for increased pressure around the brain (intracranial pressure) and treat it.

5. Seizure prevention and management.

6. Treating underlying infections (using medications such as intravenous antibiotics).

7. To restore the electrolyte levels (sodium, potassium levels).

8. To restore the acid-base balance in the body.

9. Check and maintain a normal body temperature.

10. Thiamine administration (in comatose alcoholic patients).

11. If needed, specific antidotes such as Naloxone and Flumazenil are administered.

12. Agitation control.

Once the above goals are completed, the management and treatment are tailored based on various diagnostic investigations such as blood tests and imaging. A detailed evaluation of the patient’s condition is performed to arrive at a definitive diagnosis, and specific treatment is initiated. High-level care, such as intensive care units, is required if the patient continues to be unconscious or comatose despite these initial measures.

Conclusion:

When someone becomes unconscious, they are unaware of their surroundings, unresponsive, and unarousable. The causes of unconsciousness can be reversible or permanent. Emergency care, basic life support, and advanced cardiovascular support are initiated if the patient has no pulse or breathing problems. A neurological examination is performed to identify the cause of unconsciousness and to determine treatment. Initial treatment and care of an unconscious patient include maintaining sufficient blood flow and oxygenation, restoring blood glucose and electrolyte levels, and treating underlying infections and intoxications. Definitive treatment varies depending on the underlying cause of unconsciousness.