Coma stimulation

Also termed as Sensory Stimulation or Basal Stimulation.

Coma stimulation is a collaborative approach that refers to the application of a specific structured stimulus to comatose patients for a particular period thereby improving their level of consciousness and recovery.[1][2]

The stimuli can be tactile, proprioceptive, visual, auditory, olfactory, and gustatory[3].

Sensory stimulation differs significantly in terms of duration, type of application, or mode of stimulation. The goal of this technique is the activation of the brain, improving the patient’s responsiveness, improving the transmission of the stimulus and fostering the overall recovery, and reducing the duration of recovery.[1]

Mode of stimulation[3]:[edit | edit source]

The mode of stimulation can be unimodal or bimodal.

Unimodal: Refers to the application of only one stimulus at a time.

Multimodal: Refers to the application of more than one stimulus at a given point in time. Multimodal mode of stimulation has proven to be more effective in improving the level of consciousness when compared to unimodal.

Theoretical Framework[3]:[edit | edit source]

1. Sensory Deprivation Theory- Comatose patients experience sensory deprivation as the ability to respond to stimuli- internal or external is altered. This alteration further leads to an increase in the threshold of activation of the reticular activating system. As coma stimulation is a controlled stimulation it is assumed to meet the higher threshold of these reticular neurons thereby increasing the cortical activity and improving responsiveness.

2. Neural Plasticity- Neural plasticity is the ability of the nervous system to change continually by increasing dendritic branching and the number of dendrites. Damage to the nervous system catalyzes this increase in synaptogenesis. The application of stimulus during the period of neural regrowth is assumed to maximizes the effect of plasticity. Therefore it is ideal to start coma stimulation as soon as the patient is medically stable and when the patient is closest to his time of injury.

Method of application[3][1]:[edit | edit source]

Ideal position: 30° propped up position.

Visual- Administered by using a flashlight, bright-colored objects, a mirror, and pictures of various shapes and sizes. The patient is encouraged to track these objects.

Auditory- Uses taped voice recordings of family and friends, favorite music, sounds from nature, or a tuning fork.

Olfactory- Uses perfume, spices, or aroma of food items.

Gustatory- Spices, popsicles. Swabs of appropriate items can be touched on the patient’s tongue to stimulate the taste sensation.

Tactile- Administered by rubbing different textures like satin, silk, fur, smooth metal, sandpaper, or cool or warm items over the patient's body surfaces.

Proprioception- Passive range of motion for all joints.

Duration:[edit | edit source]

Varies from 20 minutes to 3 hours per day. Can be repeated twice a day.

  1. 1.0 1.1 1.2 Hellweg S. Effectiveness of physiotherapy and occupational therapy after traumatic brain injury in the intensive care unit. Critical care research and practice. 2012 Oct;2012.
  2. Faozi E, Fadlilah S, Dwiyanto Y, Retnaningsih LN, Krisnanto PD. Effects of a Multimodal Sensory Stimulation Intervention on Glasgow Coma Scale Scores in Stroke Patients with Unconsciousness. Korean Journal of Adult Nursing. 2021 Dec 1;33(6):649-56.
  3. 3.0 3.1 3.2 3.3 Bos S. Coma stimulation. Worldviews on Evidence‐based Nursing presents the archives of Online Journal of Knowledge Synthesis for Nursing. 1997 Feb;4(1):1-6.