1. Environmental Emergencies Dr D Robinson

2. Question One 23 year old male Rescued from North Sea Unconscious RR 20 P 120, BP 90/60 SpO2 91% on 15/L 02

3. Question One What are the risk factors for drowning? (3) Age (40% <4yrs) Intoxicated adults (alcohol or drugs) Epilepsy Diabetes Depression What is the difference between drowning and near drowning? (2) Drowning is a process resulting in primary respiratory impairment from submersion / immersion in a liquid medium. Near drowning implies survival (at least temporarily).

4. Question One What is the difference between wet and dry drowning? Wet drowning involves significant aspiration of fluid into the lungs – results in pulmonary vasoconstriction, V/Q mismatch, reduced lung compliance and atelectasis. In dry drowning, a small amount of water enters the larynx and causes persistent laryngospasm and asphyxia, without significant aspiration (10% of deaths due to drowning)

5. Question One Why might this patient be hypotensive? (4) Hypovolaemia secondary to hydrostatic pressure Trauma Cardiogenic Arrythmia Sepsis Drugs / alcohol

6. Question One What investigations are indicated? (8) FBC, U&Es – ATN Glucose ECG CXR – ARDS, pneumonia ABG – hypoxia, mixed metabolic / respiratory acidosis Poison screen Core temperature ? Lateral C-spine / pelvis XR ? CT head

7. Question One What are poor prognostic indicators? (4) Extremes of age Severe acidosis (pH <7.0) Immersion > 5 minutes Coma on admission What are good prognostic signs? (4) Alert on admission Hypothermia Older children / adults Brief submersion Rapid on scene BLS (and response to resuscitation) What are the discharge criteria following episodes of near drowning? (3) Asymptomatic Normal examination Normal ABG and CXR

8. Question Two There has been an accident at the local nuclear power station Ambulance control inform you: One casualty is expected No other details at present

9. Question Two Why is it important to distinguish between external irradiation and contamination with radioactive material? Someone exposed to X-rays or gamma rays receives no further radiation after removal from the source and there is no risk of contaminating anyone else. A contaminated person is still exposed to radiation and needs urgent decontamination to minimize the risks to himself and to other people.

10. Question Two What is your immediate action? Implement Radiation Incident plan A&E Consultant, radiation physicist, media officer, (NAIR – 24 hr hotline) Prepare decontamination area (disposable sheeting on floor), turn off air conditioning Organise staff – minimum number, personal protective equipment, NOT pregnant, not to eat/drink/smoke

11. Question Two What other precautions should be taken while treating the contaminated casualty? Barrier nurse Assume patients are contaminated until they have been checked by the radiation physicist Restrict / record movement in and out of the decontamination area Ambulance crew – need to wait for monitoring of themselves and their vehicle Collect patient’s clothes and any equipment used Blood / urine samples should be specially labelled, and the labs informed of the radiation risk

12. Question Two Outline how you would decontaminate this patient (Under guidance of radiation physicist) Wounds: cover Skin: Avoid splashing, wash with soap and water, +/- scrubbing Mouth: mouthwash / soft toothbrush (do not swallow) Nose: blow nose into paper hankies Eyes: irrigate from medial to lateral Hair: shampoo +/- clip, do not shave

13. Question Two What are the features of radiation sickness? Malaise GI: nausea, diarrhoea, vomiting Skin: erythema / blistering CNS: cerebral oedema (v.high doses) What investigations should be performed if radiation sickness is suspected? FBC – low lymphocyte count Chromosome analysis

14. Question Three A diver presents four hours after his last dive with stiffness in the shoulders and elbows What is the mechanism by which decompression illness (DCI) occurs? Dissolved nitrogen in supersaturated blood and tissues is not expelled at a sufficient rate to prevent bubble formation as ambient pressure falls. These bubbles distort tissues and obstruct blood flow.

15. Question Three How may DCI present? Musculoskeletal (“The Bends”) Neurological – spinal cord involvement (back pain, motor and sensory deficit, urinary retention, priapism), cerebral air embolism (headache, seizures, LOC) Back to our patient. What features of musculoskeletal DCI may he have on examination? Itchy rash Local swelling Peau d’orange effect

16. Peau d’orange (skin of an orange)

17. Question Three Outline how you would manage this patient Oxygen Analgesia (NOT entonox) IV fluids Recompress Check buddy NOTE: in sick patients, if require ETT inflate cuff with water, treat associated hypothermia

18. Question Four 84 year old female Found collapsed at home by home help Responding to painful stimulus P50, BP 110/70

19. Question Four ECG 4 Abnormalities on ECG? (4)

20. Question Four ECG Sinus bradycardia T inversion V1/V2, aVR and aVL QT prolongation J waves (Osborn waves) What arrythmias are associated with severe hypothermia? (5) Sinus bradycardia AF / flutter / atrial ectopics Nodal rhythms AV block Ventricular ectopics VF Asystole

21. Question Four Which drugs are associated with hypothermia? (3) Ethanol Sedatives / hypnotics Phenothiazines Insulin For patients in VF with severe hypothermia, outline your strategy for defibrillation and drug treatment. (4) Give 3 initial shocks, then defer further attempts until T>30 C Withhold drugs until T>30 C Then double interval between doses Standard drug protocols once T>35 C

22. Question Five 20 year old male Brought in from nightclub Confused P 140 T 41 C

23. Question Five Define heat stroke (2) A systemic inflammatory response with a core temperature over 40.6 degrees C, accompanied by mental state change and varying levels of organ dysfunction. Which drugs are associated with heat stroke? (6) Haloperidol Antiparkinsonian Phenothiazines Diuretics Ethanol Caffeine MDMA Cocaine Amphetamines

24. Question Five Which endocrine disorders are associated with hyperthermia? (2) Thyrotoxic crisis Phaeochromocytoma What are the complications of heat stroke? (5) CVS: Arrythmias, hypotension Resp: ARDS CNS: Seizures, coma Liver / renal failure DIC Rhabdomyolysis

25. Question Five Which methods may be used to lower body temperature in patients with heat stroke? (5) Remove clothing Evaporative: warm water mist and fans Ice packs: axillae, groins, neck, scalp Cold gastric / peritoneal lavage Cardiopulmonary bypass Dantrolene: 1mg/kg, neuroleptic malignant syndrome, malignant hyperthermia, MDMA

26. Question Six 43 year old male Walking dog Hit by lightning GCS 3 at scene GCS 14 in ED

27. Question Six What kind of current is lightning? (2) Neither AC or DC, but behaves most like DC. How is lightning different from other high- voltage injuries? (2) Actual amount of energy delivered to tissues is much less with lightning - brief duration of current flow, and most of the lightning travels over the outside of the victim.

28. Question Six What is the most common cause of death from lightning strikes? (1) Cardiorespiratory arrest – asystole What is unique about the prehospital care and resuscitation of victims of lightning injury? (1) Treatment should be directed towards those that appear “dead”- nearly all victims who do not have initial cardiac arrest survive.

29. Question Six What are the ophthalmic complications of lightning injuries? (4) Mydriasis Loss of light reflex Anisocoria Horner’s syndrome Cataracts Which investigations should be performed, and what abnormalities would you expect? (5) ECG – QT prolongation, non-specific ST changes FBC, U&Es – renal impairment (rare) CK – muscle necrosis (rare) Urinalysis – myoglobinuria (rare) Cardiac enzymes – myocardial injury (rare)

30. Question Six Which patients should be admitted following lightning strikes? (4) Cardiac abnormalities Neurological abnormalities Significant burns (rare) Significant trauma (rare)