Indriya Sthana

Preamble of Indriya Sthana (Section on Determinants of Remaining Lifespan of Patients)

This section of Caraka Samhita called Indriya Sthana deals with the signs and symptoms useful in determining the remaining lifespan of patients (also called arishta lakshana). In the present era, because of advancements in medical sciences, many arishta lakshanas are well treatable and cannot be considered as "predictors" of death as they used to even a few centuries back. However, these signs and symptoms could serve as important indicators of prognosis of disease and therefore, would be helpful in the management of patients.

Life begins with the association of consciousness, or the atma, with the five fundamental elements (earth, air, fire, ether, and water, or the panchamahabhuta) and ends in the dissolution of this association. Since this union (that results in a living being) is by no means permanent and since there is always a possibility of dissolution or death anytime, Ayurvedic texts emphasized on identifying certain signs and symptoms that could forebear, with some level of certainty, imminent death. This section is dedicated to such determinants and is structured in the form of 12 chapters:

• Signs and symptoms (arishtas) of imminent death specific to pathologies afflicting sense organs that can be perceived by sensory deficiencies (e.g., varna (color), swara (voices/sounds), gandha (smell), rasa (taste), sparsha(touch),along with chhaya (complexion) and prabha (radiance)) are addressed in chapters Varnaswariya, Pushpitendriya, Parimashneeya, Indriyaneeka, Pannarupiya and Shyavnimitta.

• Clinically useful early warning signs have been mentioned in Purvarupeeya.

• Gomaychurniya, Anujyoti, Kathamanasharireeya, Avakshirsheeya and Sadyomarneeya are chapters that give examples of arishta that could be perceived on the physical level (or, are Bahyakarana) as well as on the mental, intellectual, and emotional levels (or, afflicting the Antahkarana ), with references to sakun( good / bad consequential happening)), doota( messenger), swapna ( dreams) and miscellaneous occult sciences. The evidences laid down in these chapters may establish an Ayurveda-based clinical diagnostic methodology.

It is important to note here that Indriya Sthana deals with the predictors of life, and not just determinants/symptoms of death. There are, therefore, not titled Arishta Sthana but Indriya Sthana for a reason. Indra means prana (life). The seat of prana in the body is Sneha or Ojus. Indriya (sense organs) are said to be the linga (organs) of prana. An important concept discussed in the Indriya Sthana is termed Indriyadushti (damage to the sensory system). A state of perfect health is Anirvedovarta Lakshanam (i.e., life without any indication or perception of being alive). Such a state indicates zero symptoms of being in a terminal stage of one's life.

Even though all of the determinants (i.e., signs and symptoms) cannot be explained by rational scientific parameters (as evident by the references above to paranormal and occult sciences), some of these signs and symptoms have been documented and reported as having been experienced by people in various parts of the world. Within the treatise (Charaka Samhita), physicians have been instructed to thoroughly examine the patient for certain telltale signs that indicate terminal illness and investigate using biomarkers. The treatise then advises physicians to stop any therapeutic treatment being given to such terminal patients and provide them palliative care instead.