Hypothermia, exhaustion and drowning

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1 Hypothermia, exhaustion and drowning Capita Selecta AMC Non DCI related disorders Runtime: 40 min Slides: 36 Mattijn Buwalda Anaesthesiologist-intensivist & DMP

Definition drowning is the process of experiencing respiratory impairment from submersion/ immersion in liquid the entrance of the airway is underwater, precluding the breathing of air resulting in

2 Definition drowning is the process of experiencing respiratory impairment from submersion/ immersion in liquid the entrance of the airway is underwater, precluding the breathing of air resulting in either death, morbidity or no morbidity submersion: airway below surface immersion: airway above surface Van Beek et all. A new definition of drowning: towards documentation and prevention of a global public health problem. Bull World Health Organ. 2005;83:

3 Cause of death in recr. divers Denoble PJ, Caruso JL, del. Dear G, Pieper CF, Vann RD. Common causes of open-circuit recreational diving fatalities. Undersea Hyperb Med., 2008; 35(6):

4 Why do divers drown? drowning loss of mouthpiece Equipment malfunction LOC trapped in wreck or cave N 2 narcosis O 2 toxicity Medical condition Inadequate medical Lying on self declaration out of air increased exertion Inadequate training At the surface???? forgot to check too deep Inadequate experience relative to the particular dive

5 On the surface.. no buoyancy: empty tank, empty BCD not ditching your weights BCD does not keep airway free after LOC! a well designed life jacket does which jacket do you think?

6 Lethal triad drowning hypothermia exhaustion

7 Hypothermia by definition: core temperature < 35 o C measured lower 1/3 of oesophagus rectal, bladder, tympanic thermometers are unreliable! core temperature drops < 35 o C only after min after cold water immersion. lethal condition! however, peripheral cooling is just as lethal! evolution has focused on handling hyperthermia and not hypothermia!

Thermo neutral zone In air 26-30 o C naked person no sweating or shivering still air (no wind) In water 35-35.

8 Thermo neutral zone In air o C naked person no sweating or shivering still air (no wind) In water o C naked person no sweating or shivering stagnant water (no swimming) water vs air thermal conductivity x 24 volume specific heat capacity x 3500 People cool 4-5 x faster in water compared to air

9 Cold water immersion stage 1. skin cooling stage 2. cooling of superficial nerves and muscle 0 3 min 3-30 min cold shock response: hyperventilation tachycardia hypertension loss of: strength sensation manual dexterity aspiration inability to swim or grab flotation device stage 3. deep tissue cooling > 30 min neurological impairment arrhythmias LOC > drowning Lethal hypothermia stage 4. after effects hydrostatic & cold induced diuresis Hypovolemic shock Tipton M, Golden F. The physiology of cooling in cold water. In Bierens j (ed) Drowning, prevention rescue and treatment, Springer 2014

10 Cold shock rapid immersion T < 15 o C Cold shock response cold receptors skin sympathetically mediated tachycardia hypertension gasp + hyperventilation Dive response trigeminal nerve stimulation + breath holding vagal tonus bradycardia exp. apnoea peripheral vasoconstriction temporary incapacitation swim failure importance of life jacket 2% arrhythmia dual activation sympathetic & parasympathetic autonomic conflict 62-82% arrhythmias apnoea dive duration high incidence arrhythmias Datta A and Tipton M. Respiratory responses to cold water immersion: neural pathways, interactions, and clinical consequences awake and asleep. J Appl Physiol 2006; 100: Shattock MJ and Tipton MJ. Autonomic conflict: a different way to die during cold water immersion? J Physiol 590 (2012) pp

Manual dexterity muscle strength maximum muscle output declines

after 20 min in 12 o C water nerve conduction and amplitude of

5-15 o C Vincent MJ, Tipton MJ (1988) The effects of cold

11 Manual dexterity muscle strength maximum muscle output declines 3%/ 1 o C is reduced < 27 o C (muscle temp) which will occur after 20 min in 12 o C water nerve conduction and amplitude of action potentials decline < 20 o C (nerve temp) nerve block at 5-15 o C Vincent MJ, Tipton MJ (1988) The effects of cold immersion and hand protection on grip strength. Aviat Space Environ Med 59:

12 Central hypothermia On average 30 min before onset central cooling

Rescue collapse not due to temperature afterdrop was based on rectal temp measurements rectal conductive heat loss does continue for a while does not apply to the heart perfusion of

circulatory collapse hydrostatic and cold water induced diuresis (up to 24% decrease of circulatory plasma volume) increased blood viscosity removal of constrictive wet suit activity

13 Rescue collapse not due to temperature afterdrop was based on rectal temp measurements rectal conductive heat loss does continue for a while does not apply to the heart perfusion of extremities is centrally regulated. circulatory collapse hydrostatic and cold water induced diuresis (up to 24% decrease of circulatory plasma volume) increased blood viscosity removal of constrictive wet suit activity by victim Golden FSC, Hervey GR (1981) The afterdrop and death after rescue from immersion in cold water. In: Adam JA (ed) Hypothermia ashore and afl oat. Aberdeen University Press, Aberdeen Savard GK, Cooper KE, Veale WL et al (1985) Peripheral blood fl ow during rewarming from mild hypothermia in humans. J Appl Physiol 58:4 13

14 Cold Exposure Survival Model CESM Input variables gender age BMI water temp sea state clothing protective garments swim suit 35 yrs old rough sea Tikuisis P (1995) Predicting survival time for cold exposure. Int J Biometeorol 39: Keefe AA, Tikuisis P (2008) A guide to making stochastic and single point predictions using the Cold Exposure Survival Model (CESM). Defence R&D Canada, DRDC Toronto TM

15 Natural insulation fat (30%) unperfused muscle (70%) > swimming induces heat loss! Nybo L: Brain temperature and exercise performance. Exp Physiol 2012, 97(3):

16 Heat preservation

17 Modifications in CPR reduced O 2 consumption 6% per 1 o C decrease of core temperature extreme example: neurologically intact survival after core temp 13.7 o C and 6.5 h of resuscitation modified BLS intermittent CPR < 20 o C: 5 min cpr/ 10 min no cpr < 28 o C: 5 min on/ 5 min off modified ALS < 30 o C: no drugs and only 3 defibrilation attempts o C: double drug interval: adrenaline every 6-10 min, normal defib protocol Truhlaf A et al. Resuscitation guidelines Resuscitation 2015;95:

early onset anaerobic metabolism glycogen depletion Wallingford R, Ducharme MB and Pommier E, factors

18 Exhaustion wave splash swimming distance arm muscle fatigue Main limiting factor in cold water swimming is arm muscle fatigue muscle cooling (triceps skinfold thickness is predictive) decreased muscle perfusion, early onset anaerobic metabolism glycogen depletion Wallingford R, Ducharme MB and Pommier E, factors limiting cold-water swimming distance while wearing personal flotation devices. Eur J Appl Physiol 2000;82:24-29

19 Metabolic expenditure Immersion only: negative pressure breathing central blood pooling (700 ml) reduction in static and dynamic lung compliance 65% increase work of breathing! Shivering: BMR x 5! rapid glycogen depletion > exhaustion! Anaerobic metabolism of cooled muscle Tipton M and Bradford C. Moving in extreme environments: open water swimming in cold and warm water. Extreme Physiology & Medicine 2014;3:12

20 Drowning

21 Pathophysiology of drowning 60 sec PaCO 2 up to 6 kpa PaO 2 down to 6 kpa diafragm contractions closed glottis, sealed lips arrhythmias temporary reflex laryngospasm breath holding struggle phase involuntary respiratory movements aspiration of water (1-2 ml/kg) Apnea time training sec breaking point respiratory movements cease swallowing of water Alv-cap damage huge pulmonary shunt compliance further drop in PaO 2 LOC Bierens J. pathophysiology of drowning. In Drowning, J. Bierens ed, Springer, Heidelberg, 2014

22 Graphic representation

23 Cardiopulmonary arrest after drowning compared to a cardiac cause of arrest: younger population usually in good (cardiac) condition initial trigger: asphyxia, hypoxia, acidosis, hypothermia, dive response and not myocardial ischemia! (blood is still oxygenated when circulatory arrest occurs, hence the emphasis on cardiac massage) VF/VT is rare in cardiac arrest in drowning victims Hypoxemia Bradycardia PEA Asystole Vaagenes P, Safar P, Moosy J, et al. Asphyxiation versus ventricular fibrillation cardiac arrest in dogs: differences in cerebral resuscitation effects a preliminary study. Resuscitation 1997;35:41 52 M. Gilbert, R. Busund, A. Skagseth, Nilsen PÅ, J.P. Solbø Resuscitation from accidental hypothermia of 13.7 degrees C with circulatory arrest Lancet, 355 (2000), pp

COURSE Content: self-rescue and diver stress emergency management and equipment

24 The unconscious diver controlled ascent victim usually in face down position don t put regulator back in if in, keep in controlled ascent with victims BCD RESCUE COURSE Content: self-rescue and diver stress emergency management and equipment panicked diver response in-water rescue breathing protocols egress (exits) dive accident scenarios

25 In water resuscitation in water resuscitation triples the chance of survival! towing and rescue breaths cardiac massage not possible! 5 initial rescue breaths in If shore is < 5 min away: continue rescue breaths (10/min) and towing If shore> 5 min away: one minute of rescue breaths and bring victim to shore ASAP without further CPR. Szpilman D. Soares M. In water resuscitation- it is worthwhile. Resuscitation 2004;63:25-31

BLS in drowning not breathing or gasping after drowning open airway and give 5 rescue breaths ABC in stead of CAB O 2 administration if possible AED is less important!

26 BLS in drowning not breathing or gasping after drowning open airway and give 5 rescue breaths ABC in stead of CAB O 2 administration if possible AED is less important! (VF/VT in 10% of cases) rescue breaths are difficult fluid in airway, loss of surfactant pulmonary edema/ bronchospasm low compliance, high pressures needed regurgitation of stomach contents Youn CS, Choi SP, Yim HW. Out-ofhospital cardiac arrest due to drowning: an Utstein Style report of 10 years of experience from St. Mary s Hospital. Resuscitation 2009;80:

27 Aspiration submersed active respiration is needed dry drowning probably does not exist! patient was dead before submersion rescued before termination of laryngospasm lethal volume of aspiration: average of 22 ml/kg seawater (autopsy) regurgitation of stomach content: 65% rescue breathing only 86% full CPR also source of aspiration Manolios N. Drowning and near drowning on Australian beaches patrolled by life-savers: a ten year study Med j Austr.1988;148: Model JH, Graves SA, Ketover A. Clinical course of 91 consequative near-drowning victims. Chest 1976;70:231-8 Lunetta P, Modell JH, Sajantila A. What is the incidence and significance of "Dry-Lungs" in bodies found in water? Am J Forensic Med Pathol. 2004;25:

28 Ventilation techniques Mouth to mouth expired air has 16% O 2 O 2 inhalation by rescuer Pocket mask 0 2 addition possible Lay man: 10 min learning curve 49% failure poor head extension, jaw thrust Bag valve mask lay man: poor performance especially single hand operated

29 Ventilation techniques Supra glottic airway devices I-gel use by paramedics/ professionals Endo tracheal tube golden standard in advanced life support

arrest in special circumstances. Resuscitation 95 (2015) 148 201 Calderwood HW, Modell JH, Ruiz BC.

30 Therapy after ROSC symptoms vary from mild cough to ARDS high flow O 2 by mask + reservoir bag surfactant washout: lung protective ventilation ECLS Profylactic steroids and antibiotics are not indicated Cardiac arrest in special circumstances. Resuscitation 95 (2015) Calderwood HW, Modell JH, Ruiz BC. The ineffectiveness of steroid therapy for treatment of fresh-water near-drowning. Anesthesiology Dec;43(6):

$Extracorporal Life Support (ECLS) lung injury: veno-venous ECLS refractory cardiac arrest: arterio-venous ECLS n=274 ECLS after drowning: overall survival 51% 34% pulmonary only: 71%$

31 Extracorporal Life Support (ECLS) lung injury: veno-venous ECLS refractory cardiac arrest: arterio-venous ECLS n=274 ECLS after drowning: overall survival 51% 34% pulmonary only: 71% survival 35% ROSC: 57% survival 31% refractory cardiac arrest: 23% survival Neurological status post ELS is not reported! Burke CR, et al. ECLS for victims of drowning. Resuscitation 2016;104:19-23

32 Outcome Bierens JLM. Drowning. N Engl J Med 2012;366:

33 LOC and apnea during diving all case reports: almost 100% mortality motionless submerged diver not breathing buddy separation > 75% BLS is usually initiated stopping rules layman BLS: starts breathing impossible to continue (in water) healthcare proffesional takes over or declares death

neuropschychological prognosis Outcome after resuscitation beyond 30 minutes in drowned children with cardiac arrest and hypothermia: Dutch nationwide retrospective cohort study.

34 Prolonged survival underwater rapid brain cooling 8 o C in 2 min! child submersion under ice no struggle aspiration of water swallowing of water respiratory movements continue for 70 sec following submersion? neuropschychological prognosis Outcome after resuscitation beyond 30 minutes in drowned children with cardiac arrest and hypothermia: Dutch nationwide retrospective cohort study. = poor BMJ 2015;350:h418 doi: /bmj.h418 Samuelson H, Nekludov M and levander M. Neuropsychological outcome following near-drowning in ice water: two adult case studies. J Int Neuropschy soc 2008;14: Fainer DC, Martin CG, Ivy AC (1951) Resuscitation of dogs from fresh water drowning. J Appl Physiol 3: Conn AW, Miyasaka K, Katayama M et al (1995) A canine study of cold water drowning in fresh versus salt water. Crit Care Med 12: Xu X, Tikuisis P, Giesbrecht G (1999) A mathematical model for human brain cooling during cold-water near-drowning. J Appl Physiol 86:

35 Recommended literature N Engl J Med 2012;366:

36 Thank you for listening! Slides

Biology Paper, CSE Style (Martin)

Biology Paper, CSE Style (Martin) Hypothermia, the Diving Reflex, and Survival Full title, writer s name, name of course, instructor s name, and date (all centered). Briana Martin Biology 281 Professor