JMSCR Vol||04||Issue||08||Page 12242-12248||August 2016
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JMSCR Vol||04||Issue||08||Page 12242-12248||August 2016 www.jmscr.igmpublication.org Impact Factor 5.244 Index Copernicus Value: 83.27 ISSN (e)-2347-176x ISSN (p) 2455-0450 DOI: http://dx.doi.org/10.18535/jmscr/v4i8.91 Diving Health: Principles of medical & physical fitness Authors Ibrahim A Albrethen, Ali M Aldossary, Ahmad A Alghamdi, Hussein M Alkahtani, Munairah A Alswilem, Abdullah M Alramzi, Ali A Ablowi, Hani A Alkhudhier, Ali A Alqarni Introduction on diving health and diving diseases. This The health risks of deep diving and the fitness of discussion proceeds in 5 sections: divers continue to attract the attention of 1) The study by Jankowski, Tikuisis, and Nishi. researchers. Increased deep diving for commercial, 2) Diving and Divers’ Health. military, and recreational purposes and the 3) Issues of concern in a medical assessment of persistence of existential threats to divers in the divers. underwater, hyperbaric environment, underscore 4) The study by Sekulic and Tocilj. sustained interest in diving health and improving 5) Discussion treatments for health disorders associated with diving. The Jankowski, Tikuisis and Nishi study In the article “Exercise Effects During Diving and The hypothesis that Jankowski, Tikuisis and Nishi decompression on Postdive Venous Gas Embolism” (2004) investigated was that “bubble activity Jankowski, Tikuisis, and Nishi (2004) report on observed at both the precordium and subclavian their study, in which they pursued an emerging vein sites would be reduced if moderate exercise challenge to the conventional view that exercise were performed intermittently during during diving is entirely a contributor to two well decompresssion” (pp.489, 490). In this respect, known risks in diving, decompression sickness these researchers followed up studies, which had (DCS) and venous gas embolism (VGE). Their investigated the implications of moderate exercise, research objective was to find evidence that a at intervals during the ascent phase of diving, on certain exercise regimen for divers could minimise severe events of gas bubbles in the vascular system VGE events and concomitantly DCS. of divers. Typically, these bubbles of gas derive In another study based article “Pulmonary Function from inhalation of breathing gas mixtures by divers in Military Divers: Smoking Habits and Physical during their underwater experience. Fitness Training Influence,” Sekulic and Tocilj In their experiment, Jankowski, Tikuisis and Nishi (2006) investigated the impact of physical fitness used a methodology of simulated dives by the training among smoking and non-smoking divers. subjects. This activity took place in a water filled As a follow-up of a review of the aforementioned hyperbaric chamber [a compressed air diving articles, we discuss some of the published opinions chamber], where each dive was to a pressure of 450 Ibrahim A Albrethen et al JMSCR Volume 04 Issue 08 August Page 12242 JMSCR Vol||04||Issue||08||Page 12242-12248||August 2016 kPA and had 30 minutes duration. Doppler symptoms” are present, and bubble formation in the ultrasonic bubble detectors were used to monitor inner ear causes vertigo and loss of hearing. VGE in the participants. According to D’Aoust et Petri and Andric (2003, p. 29) note that we should al. (1977) Doppler ultrasound is routine technique in qualify reports of a low incidence of DCS in the hyperbaric physiology. Its measurement principle diving community by the probability that statistics uses the frequency of reflected ultrasound from for DCS frequency are skewed by the tendency of moving intravascular bubbles (Daniels, Evans, divers “to tolerate (ie. tough-out) minor symptoms.” Hennessy and Estaugh, 1984). Irrespective of incidence, DCS matters, because, as The value of Jankowski, Tikuisis and Nishi’s study Vann, Butler, Mitchell and Moon (2011) argue, it is its addition to the development of knowledge that can cause “permanent invalidism” and “fatal could reduce the incidence of DCS, a prime hazard outcomes.” of diving. For instance, their investigation The conclusion of Jankowski, Tikuisis and Nishi suggested that exercise during the decompression (2004, p. 494) was that “moderate, intermittent phase of diving could facilitate efficient elimination exercise during decompression,” within the ascent of inert gas from the tissues, thus averting VGE and phase of diving, offers a potentially economical and DCS. practical procedure to reduce VGE and enhance In the literature of Vann, Butler, Mitchell, and diving safety. Moon (2011, p.153), DCS is induced by a “state of super-saturation,” in which there is an accumulation Diving and Divers’ Health of inert gas in tissues, over and above the level of In the literature of Gronning and Aarli (2011) deep ambient or environment pressure; this development diving is diving to depths of more than 50 m in allows inert gas to flow from the tissues. In the water. Such diving has a long history. Vaernes deep diving context, inert gases, mostly helium and (2007) notes that diving techniques have been nitrogen, are components of the breathing mixture around since antiquity. He found evidence for this for divers. in an archeological dig in Mesopotamia, dating from DCS is visible in bubbles in blood or tissue. 4500 B.C. and, in the scholarship of Aristotle, who According to Strauss and Borer (2001), in every mentioned a diving machine. From this history, theory of DCS, bubbles are a primary contributory Vaernes (2007, p. 184) traces five historical stages factor. Strauss and Borer (2001) also point out that in the development of diving: DCS and arterial gas embolism (AGE), of which 1) Breath-hold diving, also called free diving. VGE is a subset, are intertwined so closely that it is 2) Diving bells. often difficult to segregate these conditions. 3) Surface-supported or helmet diving, also DeGorordo, Vallejo-Manzur, Chanin and Varon called hard-hat diving. (2003, p.175) distinguish two categories in the 4) Self-contained underwater breathing pathophysiology of DCS: type 1 and type 2 DCS. apparatus (scuba diving). Type 1 DCS is sometimes called the ‘bends’; its 5) Saturation diving. main manifestations are “deep, aching and poorly Germonpre (2006) identifies three categories of localized musculoskeletal pain.” Usually, type 1 divers: 1) recreational divers, 2) occupational or DCS develops within one hour of a diver’s return to commercial divers, and 3) professional divers, a the surface and its manifestations, which may category in which military divers would fit. commence mildly, intensify gradually over the next Gronning and Aarli (2011, p. 18) explain that during twenty-four to thirty-six hours. Bubble formation in diving, several environmental factors impact all the skin and lymphatics causes rash and divers: “depth, time, temperature and the physical lymphoedema during type 1 DCS. In type 2 DCS, and chemical properties of the gas mixtures “focal neurological and cardio-respiratory employed [in breathing gas].” The subjects in the study by Jankowski, Tikuisis and Nishi were thirty Ibrahim A Albrethen et al JMSCR Volume 04 Issue 08 August Page 12243 JMSCR Vol||04||Issue||08||Page 12242-12248||August 2016 nine men who are representative of commercial and environment” and are a prominent part of the professional divers: twenty eight were commercial explanation for diving disorders. Collectively, these diving students; eleven were Canadian military disorders are called dysbarism. Another hazard of divers. depth for divers is gas toxicity. In the literature of Elliott (2004, p. 533) commercial According to Risdall and Gradwell (2011) many and military divers perform in a “unique investigations have led to a consensus that gases, workplace.” Commercial divers are employed in which are benign or inert at the surface of bodies of diverse activities which involve scuba, hose- water such as the sea, tend to become toxic at depth. supplied and bell diving in tasks involving Nitrogen, for instance, is prone to narcosis at depth. construction, inspection, exploration for minerals, At increased partial pressures nitrogen behaves as a and repair and maintenance of deep water structures narcotic stimulant: it produces symptoms which and mountain dams. Military divers perform in resemble alcohol intoxication, reduced manual “unusual conditions.” According to Gronning and adeptness, and diminished mental function. The Aarli (2011), in deep diving, all divers are in an underlying pathology for these impairments is environment that, on its own, can upset their attributed to an effect of gas on cell membranes. physiology and well-being. Elaborating on this Oxygen toxicity plays out in two forms, central hazardous environment, Benton and Glover (2005, nervous system (CNS) and pulmonary. The trigger p.240) point out that “the primary challenge to a for CNS oxygen toxicity is breathing of oxygen at a diver is immersion in a liquid medium” which partial pressure of 1. 50 bars (150 kPa) above the “introduces hazards such as drowning, hypothermia, lower limit for toxicity which is 0.3 bar (30kPa). and physical exhaustion.” Elliott (2004, p.533) The classic warning sign of CNS oxygen toxicity is argues that all divers must be “medically, mentally, an abrupt epileptiform convulsion. and physically fit to perform their varied tasks,” and Pulmonary oxygen toxicity is related to the duration “the primary objective” of a diving medical is to of breathing the gas and the amount of gas intake. maximise the diver’s safety underwater. In general, the starting point for pulmonary oxygen The physician in charge of the diving medical is toxicity is exposure to oxygen above 0.5 bar responsible for certification of a diver’s (50kPa) for more than twelve hours. Leading compatibility with relevant health criteria. The symptomatic signals include dry cough, tracheal examining physician should seek for divers to be in irritation, and lessening of vital capacity. The third optimal comprehensive health, because, as Vaernes of these signals contributes to the accumulation of (2007, p.184) points out, reiterating a theme in gas bubbles in the body as the performance of the studies of the diving environment, diving is lungs declines.