The treatment applied in Hyperbaric Medicine is known as Hyperbaric Oxygen Therapy (HBO) and consists of the therapeutic administration of Oxygen at a concentration of 100%, inside a Hyperbaric Chamber at an environmental pressure higher than atmospheric pressure. The European Committee for Hyperbaric Medicine (ECHM), European organism in charge of studying and defining the Indications of Hyperbaric Oxygen Therapy, Research Protocols, Common Standards for therapeutic and technical procedures, establishes in 7th European Consensus Conference on Hyperbaric Medicine, that Hyperbaric Oxygen Therapy (HBO) treatments must be administered at a minimum pressure of 2 ATA for a time of no les than 60 minutes.
Hyperbaric Medicine is based on a solid and well-established foundation, the therapeutic action obtained in Hyperbaric Oxygen Therapy treatments is based on Hyperoxia, which is produced by increasing the transport and transfer of oxygen dissolved in the blood plasma. Being in free physical form, this oxygen can be used in situations where haemoglobin transport is inefficient, which is often the case in disorders where tissue hypoxia is the cause of the pathology and its development. Contraindications and side effects of Hyperbaric Oxygen Therapy are few, well defined and easily controlled.
«Boyle’s Law» states that a t constant temperature, the pressure exerted by a gas is inversely proportional to the volume it occupies. As a consequence of the increase in ambient pressure obtained inside a Hyperbaric Chamber, there is a decrease in the volume of the air spaces of the body that are not in contact with the respiratory tract (urinary bladder, digestive tract, hearing organ and paranasal sinuses). Este efecto mecánico, tiene importantes aplicaciones clínicas en todas aquellas patologías donde exista un volumen gaseoso anormal, por ejemplo en Embolismo Gaseoso, Enfermedad Descompresiva…
According to «Henry’s Law», the amount of gas dissolved in a liquid at constant temperature is proportional to the partial pressure of the gas in the liquid. When breathing oxygen at a concentration of 100% in a Hyperbaric Chamber at an ambient pressure of 3 ATA, there is a progressive increase in oxygen concentration in the volume of oxygen dissolved and transported by the blood plasma can reach a figure 22 times greater than at atmospheric pressure, giving a total figure of approximately 6.8 ml of dissolved oxygen per 100 ml of blood. The following table shows the direct relationship between the increase in the Volume of Oxygen dissolved in blood obtained by increasing Ambient Pressure and the Inspired Oxygen Fraction:
Hyperbaric Oxygen Therapy provides an additional supply of oxygen without flow limitations or metabolic conditions that may limit the transfer or use of oxygen transported by the red blood cells. This arterial, venous and tissue hyperoxia, the increased transport and availability of dissolved oxygen in the blood plasma, the changes in gas volume, the non-hypoxemic peripheral vasoconstriction, the stimulation of Nitric Oxide formation and the high formation of antioxidants can provide a therapeutic effect in all pathologies in which there is a state of general or local tissue hypoxia as a causative or aggravating factor of the pathology. In certain pathologies, some specific therapeutic effects are produced:
Hyperbaric Medicine has been known for more than 350 years, although the scientific use of hyperbaric chambers did not begin until the middle of the 20th century. Hyperbaric Medicine began in Spain in 1923, when the Spanish Navy acquired a multiplace hyperbaric chamber, which was used regularly until the 1960s for the treatment of decompression sickness in civilian and military divers. As of 1970, Hyperbaric Chambers were acquired for civilian use in several hospitals of the National Health System, due to a case of gas gangrene presented by a patient linked to the «establishment». The Hyperbaric Chambers chosen are of the single-seat type manufactured in the UK, some of which are still in use, although their application has been reduced to acute acute processes of Carbon Monoxide Poisoning and Gas Gangrene.
A pioneer in the field of Hyperbaric Medicine is the medical Colonel Dr. Antonio de Lara Muñoz-Delgado, who after his time at the «Army Diving Center» decided to build a new Hyperbaric Chamber due to the bureaucratic difficulties in treating civilian patients in military Hyperbaric Chambers. In 1976, the new Hyperbaric Chamber was inaugurated in the «Santo y Real Hospital de la Caridad» in Cartagena, being the first Hyperbaric Unit installed in a Hospital in Spain. It is a multi-place model consisting of a body of more than 30 metres long divided into two zones with a total capacity for more than 60 patients. Each of the areas has an antechamber that allows the entry and exit of medical staff during treatments without the need to depressurise patients, and has locks for the passage of medicines and rectangular doors that allow access to patients on stretchers or wheelchairs. The Hyperbaric Chamber is still in operation today and to date, more than 600,000 Hyperbaric Oxygen Therapy treatments have been performed there under the direction of Dr. José Antonio Viqueira Caamaño, disciple and successor of the late Dr. De Lara.
Currently, the National Health System includes several hospitals with Hyperbaric Medicine Service equipped with Multiplace Hyperbaric Chambers, some of them provided by the Ministry of Defense for military and civilian use, such as the«Central Defense Hospital Gómez Ulla» in Madrid, the«General Defense Hospital of Zaragoza», the «Basic General Defense Hospital San Carlos» in Cádiz, the «Basic Defense Hospital Básico of Ferrol» and others of totally public use, such as the University Hospital Marqués de Valdecilla in Santander, the Hospital of Palamós in Girona, the Hospital of Sant Joan Despí Moisés Broggi in Barcelona, the General University Hospital of Castellón and the University Hospital of Canarias. It also includes some hospitals and clinics, which, although privately owned, are subsidized for public use, such as the Hospital El Angel in Malaga, or the Hospital Perpetuo Socorro in Alicante, among others. There are also a multitude of single-place hyperbaric chambers located in hyperbaric centers and private clinics throughout the country, although many of them do not comply with current regulations.
BIBLIOGRAPHY: Hyperbaric Society. Underwater and Hyperbaric Manual, Dr. Emilio Salas Pardo, Dr. Juan Manuel García-Cubillana de la Cruz, Dr. Fernando Samalea Pérez. Integral medicine, 17 (9): 64-80 1991, Dr. José Antonio Viqueira Caamaño, Dr. Ángel Pujante Escudero. Elsevier-Doyma FMC volume 16, number 8, October 2009.Dr. Jordi Desola. European Committee for Hyperbaric Medicine (ECHM).