Power Equation for Predicting the Risk of Central Nervous System Oxygen Toxicity at Rest
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Standard Operating Procedures for Scientific Diving
Standard Operating Procedures for Scientific Diving The University of Texas at Austin Marine Science Institute 750 Channel View Drive, Port Aransas Texas 78373 Amended January 9, 2020 1 This standard operating procedure is derived in large part from the American Academy of Underwater Sciences standard for scientific diving, published in March of 2019. FOREWORD “Since 1951 the scientific diving community has endeavored to promote safe, effective diving through self-imposed diver training and education programs. Over the years, manuals for diving safety have been circulated between organizations, revised and modified for local implementation, and have resulted in an enviable safety record. This document represents the minimal safety standards for scientific diving at the present day. As diving science progresses so must this standard, and it is the responsibility of every member of the Academy to see that it always reflects state of the art, safe diving practice.” American Academy of Underwater Sciences ACKNOWLEDGEMENTS The Academy thanks the numerous dedicated individual and organizational members for their contributions and editorial comments in the production of these standards. Revision History Approved by AAUS BOD December 2018 Available at www.aaus.org/About/Diving Standards 2 Table of Contents Volume 1 ..................................................................................................................................................... 6 Section 1.00 GENERAL POLICY ........................................................................................................................ -
Heat Stroke Heat Exhaustion
Environmental Injuries Co lin G. Ka ide, MD , FACEP, FAAEM, UHM Associate Professor of Emergency Medicine Board-Certified Specialist in Hyperbaric Medicine Specialist in Wound Care The Ohio State University Wexner Medical Center The Most Dangerous Drug Combination… Accidental Testosterone Hypothermia and Alcohol! The most likely victims… Photo: Ralf Roletschek 1 Definition of Blizzard Hypothermia of Subnormal T° when the body is unable to generate sufficient heat to sustain normal functions Core Temperature < 95°F 1979 (35°C) Most Important Temperatures Thermoregulation 95°F (35° C) Hyper/Goofy The body uses a Poikilothermic shell to maintain a Homeothermic core 90°F (32°C) Shivering Stops Maintains core T° w/in 1.8°F(1°C) 80°F (26. 5°C) Vfib, Coma Hypothalamus Skin 65°F (18°C) Asystole Constant T° 96.896.8-- 100.4° F 2 Thermoregulation The 2 most important factors Only 3 Causes! Shivering (10x increase) Decreased Heat Production Initiated by low skin temperature Increased Heat Loss Warming the skin can abolish Impaired Thermoregulation shivering! Peripheral vasoconstriction Sequesters heat Predisposing Predisposing Factors Factors Decreased Production Increased Loss –Endocrine problems Radiation Evaporation • Thyroid Conduction* • Adrenal Axis Convection** –Malnutrition *Depends on conducting material **Depends on wind velocity –Neuromuscular disease 3 Predisposing Systemic Responses CNS Factors T°< 90°F (34°C) Impaired Regulation Hyperactivity, excitability, recklessness CNS injury T°< 80°F (27°C) Hypothalamic injuries Loss of voluntary -
Environmental Injuries
Environmental Injuries Colin G. Kaide, MD, FACEP, FAAEM, UHM Associate Professor of Emergency Medicine Board-Certified Specialist in Hyperbaric Medicine Specialist in Wound Care The Ohio State University Wexner Medical Center 1 The Most Dangerous Drug Combination… Testosterone and Alcohol! The most likely victims… Photo: Ralf Roletschek Accidental Hypothermia 2 Blizzard of 1979 Definition of Hypothermia Subnormal T° when the body is unable to generate sufficient heat to sustain normal functions Core Temperature < 95°F (35°C) 3 Most Important Temperatures 95°F (35° C) Hyper/Goofy 90°F (32°C) Shivering Stops 80°F (26.5°C) Vfib, Coma 65°F(18F (18°C) AtlAsystole Thermoregulation The body uses a Poikilothermic shell to maintain a Homeothermic core Maintains core T° w/in 1.8°F(1°C) Hypothalamus Skin CttTConstant T° 96. 8- 100.4° F 4 Thermoregulation The 2 most important factors Shivering (10x increase) Initiated by low skin temperature Warming the skin can abolish shivering! Peripheral vasoconstriction Sequesters heat Only 3 Causes! Decreased Heat Production Increased Heat Loss Impaired Thermoregulation 5 Predisposing Factors Decreased Production –Endocrine problems • Thyroid • Adrenal Axis –Malnutrition –Neuromuscular disease Predisposing Factors Increased Loss RRditiadiation Evaporation Conduction* Convection** *DDdepends on cond dtitilucting material **Depends on wind velocity 6 Predisposing Factors Impaired Regulation CNS injury Hypothalamic injuries Peripheral Injury Atherosclerosis Neuropathy Interfering Agents Systemic Responses CNS -
Dysbarism - Barotrauma
DYSBARISM - BAROTRAUMA Introduction Dysbarism is the term given to medical complications of exposure to gases at higher than normal atmospheric pressure. It includes barotrauma, decompression illness and nitrogen narcosis. Barotrauma occurs as a consequence of excessive expansion or contraction of gas within enclosed body cavities. Barotrauma principally affects the: 1. Lungs (most importantly): Lung barotrauma may result in: ● Gas embolism ● Pneumomediastinum ● Pneumothorax. 2. Eyes 3. Middle / Inner ear 4. Sinuses 5. Teeth / mandible 6. GIT (rarely) Any illness that develops during or post div.ing must be considered to be diving- related until proven otherwise. Any patient with neurological symptoms in particular needs urgent referral to a specialist in hyperbaric medicine. See also separate document on Dysbarism - Decompression Illness (in Environmental folder). Terminology The term dysbarism encompasses: ● Decompression illness And ● Barotrauma And ● Nitrogen narcosis Decompression illness (DCI) includes: 1. Decompression sickness (DCS) (or in lay terms, the “bends”): ● Type I DCS: ♥ Involves the joints or skin only ● Type II DCS: ♥ Involves all other pain, neurological injury, vestibular and pulmonary symptoms. 2. Arterial gas embolism (AGE): ● Due to pulmonary barotrauma releasing air into the circulation. Epidemiology Diving is generally a safe undertaking. Serious decompression incidents occur approximately only in 1 in 10,000 dives. However, because of high participation rates, there are about 200 - 300 cases of significant decompression illness requiring treatment in Australia each year. It is estimated that 10 times this number of divers experience less severe illness after diving. Physics Boyle’s Law: The air pressure at sea level is 1 atmosphere absolute (ATA). Alternative units used for 1 ATA include: ● 101.3 kPa (SI units) ● 1.013 Bar ● 10 meters of sea water (MSW) ● 760 mm of mercury (mm Hg) ● 14.7 pounds per square inch (PSI) For every 10 meters a diver descends in seawater, the pressure increases by 1 ATA. -
Autonomic Conflict: a Different Way to Die During Cold Water Immersion
J Physiol 590.14 (2012) pp 3219–3230 3219 TOPICAL REVIEW ‘Autonomic conflict’: a different way to die during cold water immersion? Michael J. Shattock1 and Michael J. Tipton2 1Cardiovascular Division, King’s College London, London, UK 2Extreme Environments Laboratory, Department of Sports and Exercise Science, University of Portsmouth, Portsmouth, UK Abstract Cold water submersion can induce a high incidence of cardiac arrhythmias in healthy volunteers. Submersion and the release of breath holding can activate two powerful and antagonistic responses: the ‘cold shock response’ and the ‘diving response’.The former involves the activation of a sympathetically driven tachycardia while the latter promotes a parasympathetically mediated bradycardia. We propose that the strong and simultaneous activation of the two limbs of the autonomic nervous system (‘autonomic conflict’) may account for these arrhythmias and may, in some vulnerable individuals, be responsible for deaths that have previously wrongly been ascribed to drowning or hypothermia. In this review, we consider the evidence supporting this claim and also hypothesise that other environmental triggers may induce autonomic conflict and this may be more widely responsible for sudden death in individuals with other predisposing conditions. (Received 6 February 2012; accepted after revision 27 April 2012; first published online 30 April 2012) Corresponding author M. Shattock: Cardiovascular Division, King’s College London, The Rayne Institute, Lambeth Wing, St Thomas’ Hospital, London SE1 7EH, UK. Email: [email protected] Introduction: do all drowning victims drown? on average, we lose about one child a week. Historically, death in cold water was generally ascribed to hypothermia; In most countries of the world, immersion represents the more recently, description of the initial ‘cold shock’ second most common cause of accidental death in children response (Tipton, 1989b) to immersion and other factors and the third in adults (Bierens et al. -
Deep Sea Dive Ebook Free Download
DEEP SEA DIVE PDF, EPUB, EBOOK Frank Lampard | 112 pages | 07 Apr 2016 | Hachette Children's Group | 9780349132136 | English | London, United Kingdom Deep Sea Dive PDF Book Zombie Worm. Marrus orthocanna. Deep diving can mean something else in the commercial diving field. They can be found all over the world. Depth at which breathing compressed air exposes the diver to an oxygen partial pressure of 1. Retrieved 31 May Diving medicine. Arthur J. Retrieved 13 March Although commercial and military divers often operate at those depths, or even deeper, they are surface supplied. Minimal visibility is still possible far deeper. The temperature is rising in the ocean and we still don't know what kind of an impact that will have on the many species that exist in the ocean. Guiel Jr. His dive was aborted due to equipment failure. Smithsonian Institution, Washington, DC. Depth limit for a group of 2 to 3 French Level 3 recreational divers, breathing air. Underwater diving to a depth beyond the norm accepted by the associated community. Limpet mine Speargun Hawaiian sling Polespear. Michele Geraci [42]. Diving safety. Retrieved 19 September All of these considerations result in the amount of breathing gas required for deep diving being much greater than for shallow open water diving. King Crab. Atrial septal defect Effects of drugs on fitness to dive Fitness to dive Psychological fitness to dive. The bottom part which has the pilot sphere inside. List of diving environments by type Altitude diving Benign water diving Confined water diving Deep diving Inland diving Inshore diving Muck diving Night diving Open-water diving Black-water diving Blue-water diving Penetration diving Cave diving Ice diving Wreck diving Recreational dive sites Underwater environment. -
Diver Medical | Participant Questionnaire Directions
Diver Medical | Participant Questionnaire Recreational scuba diving and freediving requires good physical and mental health. There are a few medical conditions which can be hazardous while diving, listed below. Those who have, or are predisposed to, any of these conditions, should be evaluated by a physician. This Diver Medical Participant Questionnaire provides a basis to determine if you should seek out that evaluation. If you have any concerns about your diving fitness not represented on this form, consult with your physician before diving. If you are feeling ill, avoid diving. If you think you may have a contagious disease, protect yourself and others by not participating in dive training and/or dive activities. References to “diving” on this form encompass both recreational scuba diving and freediving. This form is principally designed as an initial medical screen for new divers, but is also appropriate for divers taking continuing education. For your safety, and that of others who may dive with you, answer all questions honestly. Directions Complete this questionnaire as a prerequisite to a recreational scuba diving or freediving course. Note to women: If you are pregnant, or attempting to become pregnant, do not dive. Yes I have had problems with my lungs/breathing, heart, blood, or have been diagnosed with COVID-19. No 1 Go to Box A Yes I am over 45 years of age. No 2 Go to Box B I struggle to perform moderate exercise (for example, walk 1.6 kilometer/one mile in 14 minutes 3 or swim 200 meters/yards without resting), OR I have been unable to participate in a normal Yes No physical activity due to fitness or health reasons within the past 12 months. -
The Effects of Warm and Cold Water Scuba Finning on Cardiorespiratory Responses and Energy Expenditure
AN ABSTRACT OF THE THESISOF in Caron Lee Louise Shake for the degreeof Doctor of Philosophy Education presented on April 5, 1989. Scuba Finning on Title: The Effects of Warm and Cold Water Cardiorespiratory Responses and EnergyExpenditure Redacted for privacy Abstract approved: cardiorespiratory and energy This study was designed to determine finning at expenditure responses elicited byrecreational divers while and warm (29°C) water a submaximal intensity(35% max) in cold (18°C) to par- with and without wet suits. Male divers (15) volunteered exercise ticipate in five experimentalprocedures. A maximal graded in 29°C tethered finning test, two submaximal(30 min.) finning tests tests with and without wet suits, and twosubmaximal (30 min.) finning The variables in 18°C with and without wetsuits were performed. (VE), measured were: breathing frequency(BF), minute ventilation (RER), heart rate oxygen consumption (V02)respiratory exchange ratio (HR), and core temperature (CT). Caloric expenditure (kcal) was calculated from RER and V02. A Four-Way ANOVA andrepeated measures 0.05) Two-Way design was used to analyze the data. A significant (p < A significant (p < (suit x time) interaction wasrevealed for BF. 0.01) Three-Way (suit x temp. x time)interaction was revealed forVE, V02, RER, HR, and CT. An inverse relationship exists betweenBF and VE when comparing dives with and without suits. Diving in 18°C with suitselicited higher BF and lower VE than diving in 29°Cwithout suits. V02 increased significantly during threeof the four dives. Diving without suits elicited higher V02values though this was not significant in every case. Diving in a cold environmentelicited lower RER re- higher V02 and VE. -
0. the Search Request As Presented to the Examinee
2021 Patent Infringement Risk Search – Engineering Sample Answer [This document exemplifies how to interpret the search request, the preparation and gathering of keywords and patent classes and conducting a sample search including comments of how and why using search statements.] 0. The search request as presented to the examinee: Underwater diving as an activity is seen both as an occupation (e.g. in research and oil and gas industries) and as a popular leisure activity. While sign language / hand signals are a well known way for divers to communicate, newer divers may find the signals hard to remember, and there are circumstances where a quicker or easier means to communicate would be beneficial. Your client is a manufacturer of diving masks which has developed a scheme for transmitting voice data between a plurality of divers, which transmits the voice data between the divers using LiFi technology. They want to incorporate this technology into (three different cases for the different time zone regions): a) SCUBA diving masks b) Snorkel(l)ing masks c) handheld device (e.g. torch) The client has an indemnity agreement in place with a manufacturer of LiFi transceivers e.g. in case of standard essential patents (SEPs), however they are keen to avoid litigation from infringing anybody else’s patents relating to the specific application of the LiFi technology in their own products, and as such you have been instructed to carry out a freedom-to-operate search for one of these two product lines. Their current intention is to launch one or both products in France, the UK and the USA. -
Oxygen Toxicity in Neonatal Rats: the Effect of Endotoxin Treatment on Survival During and Post-02 Exposure
0031-3998/87/2102-0 I 09$02.00/0 PEDIATRIC RESEARCH Vol. 21. No.2, 1987 Copyright© 1987 International Pediatric Research Foundation, Inc. Printed in U.S.A. Oxygen Toxicity in Neonatal Rats: The Effect of Endotoxin Treatment on Survival during and post-02 Exposure LEE FRANK Department ofMedicine, Pulmonary Research Labora10ry, University of Miami School of Medicine, Miami, Florida 33136 ABSTRACT. Neonatal rats were treated with low doses of monary 0 2 toxicity (I, 2). However, there are unique pulmonary bacterial lipopolysaccharide (endotoxin) to test for a pro complications associated with prolonged hyperoxic exposure in tective effect of endotoxin against 02 toxicity and the the neonatal animal which could importantly influence both severe inhibition of normal lung development which occurs short and long-term survival post-02 exposure. These complica during prolonged exposure to hyperoxia. The rationale for tions relate to the known inhibitory action of hyperoxia on lung the prophylactic use of endotoxin included its marked biosynthetic processes (1, 3, 4), and the morphological conse protective effect against pulmonary 0 2 toxicity in adult quences this inhibitory action has on the rapidly growing and rats and its lung growth-promoting effect in experimental differentiating newborn (animal) lung. Several studies have now pulmonary stress models. Neonatal rats (4-5 days old) demonstrated that early postnatal exposure to hyperoxia is as survived a 14-day exposure to >95% 0 2 equally well sociated with marked inhibition of the normal septation process whether treated with saline (39/51 = 76%) or with endo by which the large saccular airspaces characteristic of the new toxin (41/51 = 80%). -
Chronic Lung Disease (Bronchopulmonary Dysplasia)
Intensive Care Nursery House Staff Manual Chronic Lung Disease (Bronchopulmonary Dysplasia) was first described in 1967 as severe chronic lung disease (CLD) in preterm infants with severe Respiratory Distress Syndrome (RDS) who received treatment with 100% O2, high inspiratory ventilator pressures and no PEEP. With antenatal glucocorticoids, surfactant treatment and improved ventilatory techniques, CLD has almost disappeared in larger preterm infants and now affects very preterm infants with or without antecedent RDS. DEFINITION: CLD is defined as a need for increased oxygen: • Infants <32 weeks gestation: oxygen requirement at 36 weeks gestational age (GA) or at discharge (whichever comes first) • Infants ≥32 weeks GA: oxygen requirement at age >28 d or at discharge (whichever comes first) INCIDENCE of CLD is inversely related to birth weight and GA: Birth weight (g) Incidence of CLD* 501-750 34% *UCSF 1998-2002 751-1,000 20% 1,001-1,250 5% 1,251-1,500 3% PATHOLOGY includes areas of atelectasis and emphysema, hyperplasia of airway epithelium and interstitial edema. Late changes include interstitial fibrosis and hypertrophy of airway smooth muscle and pulmonary arteriolar musculature. ETIOLOGICAL FACTORS include: • Lung immaturity with (a) ↑ susceptibility to damage from oxygen, barotrauma and volutrauma, (b) surfactant deficiency and (c) immature antioxidant defenses. • Oxygen toxicity • Barotrauma and volutrauma • Pulmonary edema (excessive fluid administration, patent ductus arteriosus) • Inflammation (multiple associated biochemical -
Delayed Treatment of Decompression Sickness with Short, No-Air-Break Tables: Review of 140 Cases
REVIEW ARTICLE Delayed Treatment of Decompression Sickness with Short, No-Air-Break Tables: Review of 140 Cases Paul Cianci and John B. Slade,Jr. CIANCI P, SLADE JR JB. Delayed treatment of decompression sick- increasing frequency, often having dived very provoc- ness with short, no-air-break tables: review of 140 cases. Aviat Space ative profiles, many suffering from severe DCS, and Environ Med 2006; 77:1003–8. Introduction: Most cases of decompression sickness (DCS) in the U.S. with long delays to treatment. are treated with hyperbaric oxygen using U.S. Navy Treatment Tables 5 In 1963 and 1964, the Navy Experimental Dive Unit and 6, although detailed analysis shows that those tables were based on received reports of 133 cases of DCS in which the stan- limited data. We reviewed the development of these protocols and offer dard USN tables at the time were used (28). Full relief an alternative treatment table more suitable for monoplace chambers did not result in 24% of initial recompressions. When that has proven effective in the treatment of DCS in patients presenting to our facility. Methods: We reviewed the outcomes for 140 cases of outcomes using USN Tables 3 and 4 were analyzed, a DCS in civilian divers treated with the shorter tables at our facility from 47% incidence of failure of the first treatment was January 1983 through December 2002. Results: Onset of symptoms noted. However, there were no instances of treatment averaged 9.3 h after surfacing. At presentation, 44% of the patients failure when DCS had occurred following rigid USN demonstrated mental aberration.