Hypothermia was first applied to the human in 1940 by Smith and Fay in an attempt to affect the growth of malignant tumours, and found its most important application firstly in open cardiac surgery and latterly in neurosurgery. The first results regarding the use of hypothermia in neurosurgery were reported at the First Inter national Congress of Neurological Sciences held in Brussels in 1957. The same subject was again considered at the annual meeting of the Societe de Neurochirurgie de Langue Franl}aise held in Montpellier in'1962. When I was charged with the task of organizing the Symposium at the Second European Congress of Neurosurgery, I thought it ad visable to put forward again the problem of the use of hypothermia in neurosurgery. Though this procedure had rapidly become popular and a mass of publications from the most important neurosurgical centres of the world had appeared, many problems remained un solved, and in particular those related to the choice of cases to be treated, the usefulness of the procedure and its possible dangers. I. Pathophysiology of Hypothermia.- 1. General Physiology of Hypothermia.- 2. Pathophysiology of the Central Nervous System During Hypothermia.- 3. Neurological Observations During Hypothermia.- II. Hypothermia for Neurosurgical Operations.- 1a. Changes in the Blood Clotting Mechanism During Mod-erate Hypothermia for Neurosurgical Operations.- 1b. Methods of Moderate Hypothermia in Neuro anaesthesia. Clinical Observations on Physiological and Metabolic Changes.- 1c. Moderate Hypothermia in Neurosurgical Operations: Indications and Results.- 2. Physiopathology, Methods and Clinical Results of Selective Brain Cooling.- 3. Profound Hypothermia and Total Circulatory Arrest in Neurosurgery: Methods, Results, and Physiologic Effects.- III. Hypothermia as a Therapeutic Procedure.- Moderate Hypothermia in Craniocerebral Trauma.- Final Remarks on the Clinical Use of Hypothermia in Neurosurgery.
