EMS Medical Control Rounds

1. EMS Medical Control Rounds June 7, 2012 Domenic Martinello, MD Anna-Jaques Hospital

2. Agenda • Old Business • New Business • Wiki • 12-Lead Test! • Acute CVA Refresher • Interesting Case • Case Discussion • Closing

3. Old Business • Currently no old business • Anyone have any they would like to discuss?

4. New Business • Wiki is up • http://ajh-ems-wiki.wikispaces.com/ • EMS Test is available (On wiki!) • Yes the test is MANDATORY! • Due by the Skills Review! • Please sign up and join in the discussion! • Please TIME all trauma activations • This is something ACS would like us to do • Its also good practice • You can get the time from the secretary if needed since we mark the activation time as well. • SKILLS LAB IN SEPT!

5. CVA Refresher Required yearly 

6. Why We Keep Talking About Stroke/CVA • This graph says it all (Door  CT Time)

7. Stroke • Also known as a Cerebrovascular Accident (CVA) • Defined as a rapid loss of neurologic function due to a disturbance of blood flow to the brain • May be ischemic or haemorrhagic • Is a TRUE emergency, especially in light of new treatments

8. NIH Stroke Scale • NIH Stroke scale is a test which helps to determine the extent of a stroke and also to determine candidacy for thrombolytics. • Often too cumbersome to conduct in the field, but you should be familiar with it! • It should ideally be conducted in the order indicated

9. Stroke Scale Step 1a • Level of consciousness • 0 points: Patient is alert • 1 point: requires minor stimulation but able to follow commands • 2 points: obtunded and unable to follow commands without repeated stimuli • 3 points: Unresponsive or posturing motions only

10. Stroke Scale 1b • LOC Questions • Ask the current month and patient age • 0 points: both correct • 1 point: answers one correctly • 2 points: can not answer either question • Note: If unable to speak for any reason (except if they have aphasia) they get 1 point. This includes intubation. Aphasia technically gets a 2.

11. Stroke Scale 1c • LOC Commands • Ask patient to open and close eyes, and conduct hand grasp (with unaffected hand if there is defecit) • 0 points: can do both • 1 point: can follow 1 command • 2 points: unable to follow either command • Note: you may use ANY 1-step command to substitute above. ANY attempt at following the command, even if ineffective, is considered following the command

12. Stroke Scale 2 • Horizontal Eye Movement • Have patient follow and object right and left • 0 points: able to follow completely • 1 point: partial gaze palsy in one or both eyes • 2 points: fixed deviation or complete gaze paresis

13. Stroke Scale 3 • Visual Fields • Must test 4 quadrants in each eye (superomedial, superolateral, inferomedial, inferolateral) – these will be explained on next page! • 0 points: no visual loss • 1 point: partial hemianopia (quadrant or sector defect or partial field in both eyes) • 2 points: complete hemianopia (dense defect or homonymous hemianopia) • 3 points: bilateral hemianopia or bilateral field defects in BOTH eyes • Hemianopsia/hemianopia is loss of ½ of a visual field in an eye.

14. Vision Exam • It is complex but here it is:

15. Stroke Scale 4 • Facial Palsy • Have patient smile or otherwise lift cheeks • If patient can not understand try noxious stimuli (bad smelling object?) • 0 points: symmetric movement • 1 point: mild paralysis (loss of nasolabial crease, asymmetric smile) • 2 points: near or total lower face paralysis • 3 points: upper and lower face paralysis • Note: bilateral symptoms are VERY rare but certainly possible!

16. Stroke Scale 5 (a/b) • Arm Motor testing • 5a left arm, 5b right arm • Have patient hold arms parallel with the ground (or if laying, at 45 degrees elevated), palms down, for 10 seconds • 0 points: no drift • 1 point: Drifts within 10 seconds, does NOT hit bed or other supporting structure • 2 points: effort against gravity but drifts to bed • 3 points: no effort against gravity (but able to move) • 4 points: flaccid paralysis • UNK (or some say 9 points): no arm due to amputation or unable to move due to trauma or joint fusion

17. Stroke Scale 6 a/b • Lower Extremity Strength • 6a left leg, 6b right leg • Always tested supine, have patient elevate leg to 30 degrees and hold for 10 seconds • 0 points: No drift • 1 point: drift but does NOT hit bed • 2 points: falls to bed but resists gravity • 3 points: unable to resist gravity, able to move • 4 points: flaccid paralysis • UNK / 9 points: joint fusion, unable to move due to pre-existing condition, amputation

18. Stroke Scale 7 • Limb Ataxia • Finger-nose-finger and heel-shin testing • Do in each extremity • 0 points: no defecits • 1 point: single limb ataxia • 2 points: ataxia of 2 limbs • UNK/9 points: no limb, fusion, etc

19. Stroke Scale 8 • Sensory • Test arms (not hands), face, legs, trunk • Use pinprick sensation or other noxious stimuli • 0 points: no sensory loss • 1 point: mild to moderate sensory loss (sharp feels dull, decreased intensity, but has sensation) • 2 points: total loss of sensation (not aware of being touched) • Note: patients with quadriplegia and those in deeply comatose states get a 2 by default

20. Stroke Scale 9 • Best Language • Ask them to describe picture or read a series of sentences • If visual loss place familiar objects in hand and have them name; if mute have them try and write. • This is a test of comprehension, NOT of the clarity of speech (that is next) • 0 points: normal • 1 point: reduction of speech and/or comprehension (mild aphasia) with ability to communicate [partially] • 2 points: severe aphasia. Broken speech, minimal communication • 3 points: global aphasia (mute)

21. Stroke Scale 10 • Dysarthria • Have patient read a series of words from a piece of paper • 0 points: clear speech • 1 point: mild slurring but understandable • 2 points: severe dysarthria with unintelligible words or mute (not related to a primary aphasia) • UNK / 9 points: intubated or other inability to follow the instructions

22. Stroke Scale 11 • Extinction / Inattention (formerly Neglect) • Often not tested per se but is noted during remainder of exam. • Inattention: Patient often does not attend one side of the body, or when asked to draw a clock-face patient will draw ½ normally and the other ½ will be unintelligible or all bunched up (see next page) • Extinction: touching both sides at same time yields sensation only on one side • 0 points: no problems • 1 point: mild isolated inattention • 2 points: complete hemineglect, may not recognize one side of the body as familiar

23. Hemi Neglect  Cross out ALL the single lines

24. And that’s it! • The total score is used initially and repeated over time. • Less than 4 is considered very mild symptoms (often not thrombolytic candidate) • Greater than 24 (some say 22) is considered SEVERE, and often also is considered too much risk to benefit • Amherst FD has developed a great stroke policy, please review it and know it well!

25. Clinical Case A Curious Case of “Feeling Unwell”

26. Intro • You are called to a private residence for a 91 year old female who feels unwell. • Patient is able to communicate with dispatch without problems and aside from mild nausea says that her only recent symptoms were a mild headache that responded to OTC pain reliever yesterday. Not present now.

27. Arrival • You arrive to find a mildly demented 91 year old woman who is living independently. • Daughter arrives shortly afterward stating that the patient called her saying she was nauseated and felt unwell. • No other complaints

28. So, now what? • Would you: • IV • EKG (12 lead) • Meds • Monitor • Immobilize • ?

29. Enroute • You have an uneventful ride to the hospital. • However, a second family member meets your crew as you are walking in and says she is concerned her mother took too much of her OTC headache medication. • All medications are accounted for except that there is now an empty bottle of “Headache Plus” which was purchased yesterday (40 tablets)

30. So… • What do you think she took?

31. What she took: • Each tablet contains: • 250 mg of acetaminophen (APAP) • Goes by brand name “Tylenol”® • 250 mg of acetyl salicylic acid (ASA) • Standard aspirin • 50 mg of 1,3,7-trimethylxanthine (caffeine) • Also known as “go-juice” • Is about 2/3 of a cup of coffee or ½ espresso

32. So.. Is this a problem? • Total amount in 24 hours: • APAP: 10g • ASA: 10g • Caffeine: 2g • Toxic Thresholds: • APAP: 4g • ASA: 150mg/kg • Patient was 60kg • 9g for this patient • Caffeine: • 500mg is considered “excessive: • 1g is often fatal in humans

33. So, what we have: • Combination APAP and ASA overdose • So… lets talk about each one separately and then we will talk about the treatment for this unique combination overdose

34. Tylenol Toxicity One of the most common overdoses worldwide

35. Paracetamol Toxicity • Or what we in the US call acetaminophen! (brand name Tylenol®) • Often abbreviated APAP (which I will use) • N-Acetyl-Para-Amino-Phenol • Looks like:  Amino Group Acetyl Group Phenol Group 

36. APAP • Taken in normal doses APAP is extremely safe • In therapeutic (<4g or <200mg/kg) doses it undergoes Phase II drug metabolism (what we call “conjugation reaction) • Conjugates with sulfate and glucuronide • Small amount through the cytochrome P450 system (this will be important)

37. APAP Metabolism • In the cytochrome P450 system (5% of normal APAP metabolism) the APAP is converted to a highly reactive (read: toxic) intermediate chemical: • N-acetyl-p-benzoquinoneimine • NAPQI for short • This NAPQI, under normal dosing, is immediately conjugated by glutathione (read: detoxified) and then forms harmless cysteine and mercapturic acid conjugates

38. In simpler terms: • A picture: Cytochrome P450  NAPQI 

39. In APAP Overdose • Sulfate and glucuronide pathways are saturated and metabolism is shunted through the cytochrome P450 system • This would be fine under normal circumstances since the NAPQI would be conjugated with glutathione • Glutathione is only available in limited amounts, and is rapidly depleted in overdose • In animal studies depletion to <70% of glutathione stores has been shown to cause liver toxicity when APAP is ingested • NAPQI is left free in the liver and reacts with cell membranes causing hepatic damage, failure, and hepatic necrosis

40. Toxidrome of APAP overdose • Three Phases of Overdose: • Phase I (<24 hours) • Nausea, vomiting, pallor, sweating • Minimal symptoms if any • Phase II (24-72 hours) • RUQ pain, increased LFTs (transaminases), increased INR, acute renal failure • Phase III (>72 hours, usually 3-5 days) • Massive hepatic necrosis • Leads to liver failure, hepatorenal syndrome, sepsis, death

41. Workup • Aside from detailed history (time of overdose, amount, coingestions, etc) the single most important lab if available is a 4-hour APAP level • Plotted on a nomogram to determine if treatment is necessary

42. Nomogram • US:

43. Treatment • So, you have a 4 hour APAP >140mg/L or significant risk and unable to obtain a 4-hour level (too soon or too late) • Fortunately there are some great treatment options!

44. First things first • Labs are drawn • CBC, Chem 21 (LFT’s), • APAP • Possible coingestion levels (often more than one in intentional overdoses… or like our case), • INR (shows early liver injury)

45. If RECENT overdose (<2h) • Gastric decontamination with activated charcoal • Patient must be awake, alert, and protecting airway • Charcoal aspiration is far more dangerous than APAP overdose, and we have an antidote, so this is often discarded in single drug ingestions • If you give oral charcoal you can NOT give the oral form of the antidote (it is absorbed!)

46. Next Step… • NAC (N-acetyl-cysteine) • Replenishes glutathione stores rapidly • Works best if given within 8 hours • Given up to 48 hours • There are both IV and PO forms • IV more expensive and more likely to cause an anaphylactiod reaction • PO is bound by charcoal and smells awful (like rotten eggs)

47. Long term • Treatment of APAP overdose with NAC is nearly 100% successful within 8 hours, and still highly effective out to 2 days. • Failed therapy typically requires liver transplant though some people will spontaneously recover and have some liver function left

48. That’s it! • Questions before we move on?

49. Aspirin Toxicity A much messier endeavour

50. Aspirin • Also known as acetylsalicylic acid and abbreviated ASA • Trade name is Aspirin though used generically • Salicylate class drug • Acts as an anti-inflammatory • (inhibits COX-1 and COX-2) • Decreases platelet aggregation (inhibitor of thromboxane) • Interesting note: salicylates have similar mechanism of action on COX and thromboxane as NSAIDS with one difference: NSAIDS bind reversibly, and ASA/salicylates do so irreversibly • This is why we use ASA for cardiovascular event protection and not ibuprofen or naproxen.