Wait 30 Minutes after Eating

Transcription

1 Wait 30 Minutes after Eating The perils of aquatic recreation Matthew Brown MD LT MC (UMO/DMO) USN 13 NOV 2017

2 The opinions and conclusions included in this presentation are my own and should not be construed as the opinions of the United States Navy nor the Government of the United States of America I have no financial disclosures

3 Who Am I? Undersea Medical Officer Dive School Submarine Support Command Water Enthusiast

4 Many Ways to Have Fun

5 Many Ways to Die

6 Sun Coral Waves Weather Tides Environment

7 Sun 6,000-14,000 tons of sunscreen washes off swimmers, SCUBA divers, and snorkelers into coral reef environments each year Oxybenzone- stops reproduction, bleaching, damage DNA Butylparaben- bleaching Octinoxate (Ethylhexyl methoxycinnamate)- bleaching 4-methylbenzylidene camphor (4MBC)- bleaching

8 Coral Basic first aid Irrigate, clean, clean, clean and clean Counsel it may take longer than normal to heal Antibiotics choice driven by depth of injury, foreign material, length of time prior to presentation.

9 Aquatic Bacteria Staphlococcus Streptococcus Vibrio sp Leptospirosis Do not go in warm/brakish/any water with an open wound

10 Waves (5 years) Aquatic activities leading cause of spinal cord injuries 208 spinal cord injuries on Hawaiian beaches 78% of aquatic spinal cord injuries are of visitors Average of 32 visitors injured a year Drowning Mortality determined by EMS response time Trauma response

11 Weather and Tides Pay attention Ask about conditions When in doubt don t go out Use the buddy system Have communication devices (radio, phone, emergency kit, etc.)

12 Sharks Cone shells Jellyfish Fauna

13 Shark Attack Jan Dec 2016 (7 years) 59 shark attacks 3 FATALITIES Vast majority of these attacks on surfers Snorkeling, Paddleboarding, Swimming Trauma response

14 Cone Shells 34 species in Hawaiian waters Only 2-3 are dangerously venomous Live in shallow reefs, nighttime predators Main danger is picking them up Textile Cone Shell Striated Cone Shell

15 Cone Shells Painless wound to excruciating pain ASCENDING numbness and tingling Can advance to diffuse skeletal muscle paralysis and death 1-6 hours is magic window Supportive BLS care, Immobilize extremity, apply pressure bandage. No antivenin

16 Bluebottles (Man-o-war) Mild itch to throbbing pain Nematocysts on tentacles can penetrate up to 1 mm into tissues Capable of discharging for up to 2 weeks University of Hawaii 2017 Treat with Undiluted Vinegar Treat with heat

17 Box Jellyfish For the 8-11 days after a full moon All shores susceptible, Waikiki infamous Painful Porins- Can cause holes in RBCs leaking potassium causing Hyperkalemia Avoid epinephrine Same initial treatment

18 Diving

19 PV=nRT Boyle s Law For any gas at a constant temperature, the volume of a gas will vary inversely with the pressure Charles Law For any gas at a constant pressure, the volume of the gas will vary directly with absolute temperature Gay-Lussac s Law For any gas at a constant volume, the pressure of the gas will vary directly with the absolute temperature Dalton s Law The total pressure exerted by a mixture of gases is equal to the sum of the pressures of each of the different gases making up the mixture, with each gas acting as if it alone was present and occupied the total volume. Henry s Law The amount of any given gas that will dissolve in a liquid at a given temperature is directly proportional to the partial pressure of that gas

20 Boyle s Law and Henry s Law

21 Middle Ear Barotrauma On descent (more common) or ascent Different Grades 3-30 days recovery

22 Decompression Sickness Two types of Decompression Sickness Type 1 Type 2 Both are treated the same way Recompression and 100% Oxygen

23 Pulmonary Over Inflation Syndrome Rupture of lung intima, can lead to tension pneumothorax. Arterial Gas Embolism Treated in similar way as DCS, recompression, but depth is main goal.

24 Diver With Neuro Symptoms or Unresponsive DCS Type 2 AGE Other medical cause, normal ddx

25 Works Cited Cone Snail. Maui Ocean Center, mauioceancenter.com/marineanimals/invertebrates/cone-snail-2/. Echinoderms. Guide/Invertebrates/Echinoderms/Wana/. Keeping Hawaii Seafood Safe. hawaiiseafood.org/uploads/keeping%20hawaii%20seafood%20safe%20to%20eat.pdf. Injury Prevention. Recognition and Treatment of Diving Casualties Lecture Series. Naval Diving and Salvage Training Center.August-November Wilcox C.L., Headlam J.L., Doyle T.K. and Yanagihara A.A. Assessing the Efficacy of First-Aid Measures in Physalia sp. Envenomation, Using Solution- and Blood Agarose-Based Models. Toxins 2017, 9(5), 149 All images obtained through google images search

26 Thank You!

27 Decompression Illness Term proposed by TJR Francis and D Smith in 1991 to encompass DCS and AGE

28 3 factors of inert gas absorption Depth (pressure) Time at depth Level of inert gas exposure (initial partial pressure of gas mixture) Air 21% O2 79% N2

29 Diving Physics Pressure is most important environmental variable P=F/A Hydrostatic (gauge) pressure- force exerted by above water (water column) 33 fsw/34ffw= 1 ata Absolute pressure= gauge pressure plus the atmospheric pressure

30 Decompression During the ascent of a dive, inert gas, which has been dissolved under depth pressure into tissues, comes out of solution. Supersaturation occurs if rate of ambient pressure reduction exceeds the rate of gas washout from tissues. Can lead to Intravascular and Extravascular bubble formation

31 Bubble Formation Two Leading Theories Denovo Pre-existing, stable gas micronuclei More likely source for most bubbles Don t need as large amount of supersaturation

32 Decompression Sickness (DCS) Pathologic response to the formation of bubbles from gas dissolved in tissue due to a reduction in ambient pressure. Also called Decompression illness, dysbarism, the bends, Caisson s disease, Compressed Air Illness

33 Decompression Sickness First used by BHC Matthews, British physiologist for RAF in 1939 Type 1 and 2 classification by Golding et al in 1960

34 Type 1 Pain in or around the joint Skin symptoms, fatigue, lymphatic manifestations

35 Type 1 Musculoskeletal S/Sx Dull, vague, deep aching Constant, no relief Appendicular skeleton Pain the ONLY symptom

36 Type 1 Cutaneous Itching and mild urticaria Deep red or purple marbling or mottling May spread peripherally

37 Type 1 Lymphatic Rare Localized swelling and pain with lymph node and contingent areas Swelling of face, breast, abdominal areas, extremities Skin changes

38 Type 2 More Serious Neurologic, Pulmonary, Inner Ear Can result in Hemodynamic compromise

39 Type 2 Pulmonary Rare Emergency ascents from long deep dives with large omitted decompression Caisson workers Substernal discomfort, cough, pain with inspiration and expiration, can progress to rapid cardiovascular collapse

40 Type 2 Neurologic Spinal cord Paresthesias, numbness Multifocal Most not associated with specific level Cerebral Mental status changes CN deficits Similar to stroke symptoms Upper motor neuron signs Multiple locations in the brain affected at one time (localization problems)

41 DCS Risk Factors Depth Increased time at depth Hot conditions Exercise at depth- increased gas uptake Increased BMI Dehydration Minimum depth of fsw Ikeda T et al 1993 Eckenhoff RG et al 1986

42 Latency of DCS Faster after deep, brief dives Over hours to days after long shallow dives 90% within 24 hours CNS DCS shorter latency 80% within 1 hour More than half within 10 mins

43 Arterial Gas Embolism Continuum of symptoms Pulmonary Barotrauma Subcutaneous Emphysema Embolism

44 Senses Sound travels 4.5x faster underwater loss of directional cues. Loss of color by wavelength- R,O,Y,G,B

45 Scombroid Buildup of histamine in the fish Heat/cooking does not affect preformed toxin Peppery or spicy taste Itching of face, burning throat, nausea, vomiting, abdominal cramps, diarrhea, headache, pounding heart, flushing, weakness. No fatalities reported Responds to antihistamines Mahimahi, Tuna, Blue marlin, Big eye scad, wahoo

46 Ciguatera Fish containing Ciguatoxin- a nuerotoxin Formed by Gambierodiscus toxicus (dinoflagellate on coral reef, algae) Reversal of temperature sensation, decreased sensation, painful muscles, nausea, vomiting, diarrhea, chills, sweating, dizziness, metallic taste Symptoms can last from days to months. Usually from recreational fish Talk with your bait shop about outbreaks State health advisories Peacock grouper, gold ring surgeonfish, large and small jacks, seabass, goatfish