Criteria and Practical Guidance for Determination of Brain Death in Adults (2nd Edition)

0
0
0

Criteria and Practical Guidance for Determination of Brain Death in Adults (2nd Edition)

Introduction
Brain death is defined as the irreversible loss of all functions of the entire brain, including the brainstem. The determination of brain death is a critical medical procedure that requires strict adherence to standardized criteria and protocols. In 2013, the Brain Injury Evaluation Quality Control Center of the National Health Commission (BQCC) published the first edition of “Criteria and Practical Guidance for Determination of Brain Death in Adults” in the Chinese Medical Journal. This document established the standard for brain death determination in China. Based on five years of clinical practice, quality control analysis of brain death cases, and expert committee recommendations, the BQCC revised and updated the guidelines in 2018. This second edition aims to further standardize and promote brain death determination in China.

Part I: Criteria for Determination of Brain Death

I. Prerequisites for Determination
The determination of brain death requires two essential prerequisites:
A. The cause of coma must be known. Primary causes include brain trauma, cerebral vascular disease, and anoxic encephalopathy due to cardiac arrest, anesthetic accidents, drowning, or asphyxia. Brain death cannot be declared if the cause of coma is unknown.
B. Reversible coma must be excluded. Reversible causes include acute intoxication (e.g., carbon monoxide poisoning, sedative hypnotic poisoning), shock, hypothermia (core temperature ≤32°C), severe electrolyte and acid-base disturbances, and metabolic or endocrine disorders (e.g., hepatic encephalopathy, hypoglycemic encephalopathy).

II. Clinical Diagnosis
The clinical diagnosis of brain death must fulfill three conditions:
A. Deep coma: No motor responses to noxious stimuli on the face, and a Glasgow Coma Scale score of 3.
B. Absence of brainstem reflexes: This includes the pupillary light reflex, corneal reflex, oculocephalic reflex, oculovestibular reflex, and cough reflex.
C. No spontaneous respiration: The patient must be completely dependent on mechanical ventilation, and apnea must be confirmed through an apnea test.

III. Ancillary Tests
At least two of the following three confirmatory tests must support the diagnosis of brain death:
A. Electroencephalogram (EEG): Electrical silence, defined as no EEG activity over 2μV.
B. Short-latency somatosensory evoked potential (SLSEP): Bilateral N9 and/or N13 waves are present, while P14, N18, and N20 waves are absent.
C. Transcranial Doppler (TCD) sonography: Blood flow in the intracranial anterior and posterior circulation demonstrates reverberating flow, small systolic spikes, or the absence of blood flow signals.

IV. Time of Determination
If the clinical diagnosis and confirmatory tests fulfill the criteria, brain death can be declared. If the clinical diagnosis is incomplete, additional ancillary tests should be performed, and a repeat determination should be conducted 6 hours after the first exam. At least one apnea test must confirm the absence of spontaneous respiration.

Part II: Practical Guidance for Determination of Brain Death

I. Prerequisites
A. The cause of coma must be identified through a thorough clinical evaluation and diagnostic workup.
B. Reversible causes of coma must be ruled out through appropriate testing and treatment.

II. Clinical Evaluation
A. Deep Coma

  1. Examination: Apply noxious stimuli (e.g., pressing the supraorbital incisure or needling the face) and observe for motor responses.
  2. Pitfalls: Avoid stimuli below the neck, as spinal reflexes may persist. Differentiate spinal reflexes from spontaneous movements.

B. Absence of Brainstem Reflexes

  1. Pupillary Light Reflex: Illuminate each pupil and observe for direct and indirect light reflexes.
  2. Corneal Reflex: Touch the cornea with a cotton swab and observe for a blink response.
  3. Oculocephalic Reflex: Rotate the head and observe for eye movements.
  4. Oculovestibular Reflex: Irrigate the external auditory canal with cold saline and observe for nystagmus.
  5. Cough Reflex: Stimulate the tracheal mucosa and observe for a cough response.

C. Apnea Test

  1. Prerequisites: Ensure core body temperature ≥36.5°C, systolic blood pressure ≥90 mmHg, and adequate oxygenation (PaO2 ≥200 mmHg).
  2. Procedure: Disconnect the patient from the ventilator, deliver 100% oxygen, and observe for respiratory movements. Measure PaCO2 after 8–10 minutes.
  3. Determination: Apnea is confirmed if PaCO2 ≥60 mmHg or 20 mmHg above baseline without respiratory movements.

III. Ancillary Tests
A. Electroencephalogram (EEG)

  1. Environmental Conditions: Use a separate power supply and minimize interference.
  2. Parameter Settings: Place electrodes according to the international 10–20 system, set high-frequency filter between 30 Hz and 75 Hz, and low-frequency filter at 0.5 Hz.
  3. Procedure: Perform a 30-minute recording with somatosensory and auditory stimuli.
  4. Determination: Electrical silence supports the diagnosis of brain death.

B. Short-Latency Somatosensory Evoked Potential (SLSEP)

  1. Environmental Requirements: Control room temperature between 20°C and 25°C.
  2. Recording Techniques: Place electrodes according to the international 10–20 system and stimulate the median nerve.
  3. Procedure: Perform at least 500–1000 averages for each time point.
  4. Determination: Absence of P14, N18, and N20 waves supports the diagnosis of brain death.

C. Transcranial Doppler (TCD)

  1. Equipment: Use a 1.6 or 2 MHz pulse-wave Doppler probe.
  2. Parameter Settings: Adjust sampling volume, gaining intensity, and speed scale plate.
  3. Checking Positions: Use temporal, occipital, and ocular windows to detect intracranial arteries.
  4. Determination: Reverberating flow, small systolic spikes, or absence of blood flow signals support the diagnosis of brain death.

IV. Procedures for Determination
The determination of brain death consists of three steps:

  1. Clinical evaluation fulfilling the criteria (deep coma, absence of brainstem reflexes, and no spontaneous respiration).
  2. At least two ancillary tests supporting the diagnosis.
  3. Confirmation of apnea through the apnea test.

V. Personnel for Determination
At least two physicians with standardized training and at least five years of clinical experience must participate in the determination of brain death.

Conclusion
The 2018 edition of “Criteria and Practical Guidance for Determination of Brain Death in Adults” provides a comprehensive and standardized approach to brain death determination in China. By adhering to these guidelines, healthcare professionals can ensure accurate and consistent diagnoses, thereby promoting ethical and legal practices in end-of-life care.

doi.org/10.1097/CM9.0000000000000014

Was this helpful?

0 / 0