Emergency medicine

Emergency Medicine
Clerkship Handbook
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Emergency Medicine Clerkship Seminar Series Objectives All seminars are small group, case based sessions, with an emphasis on interaction 1. Toxicology Describe the specific components of ABC’s as they refer to emergency assessment. Take a goal directed history in order to identify the offending toxin, and quantifying the amount of toxin ingested and the tempo of symptom progression Outline the common toxidromes (ASA, Acetominophen, TCA, Cocaine, Benzodiazepines) with the findings on physical exam . Basic treatment will be outlined, but in not an objective Describe the indications for charcoal, multi-dose charcoal, gastric lavage, and whole bowel irrigation Describe the role of the lab and “tox screens” in the assessment of poisoned patients. 2. X-Rays Develop and organized approach for interpretation of plain x-ray films. Extremity and chest films of common types of injuries will be the focus. Although treatment will be discussed, this is not the emphasis of the seminar 3. Mini ACLS Develop a differential diagnosis for life threatening causes of chest pain Discuss various ECG’s and the role of 15 lead ECG Describe the indications and contraindications for thrombolysis Discuss the ECG and rhythm strip characteristics and treatment of Ventricular Fibrillation Canadian Triage and Acuity Scale (CTAS) This can be found at the top corner of all charts in emerg – aside from their other uses, you may find these triage designations useful in determining what type of patient presentation
awaits you.
Level I - Resuscitation
Conditions that are threats to life or limb (or imminent risk of deterioration) requiring immediate
aggressive interventions.
Time to physician IMMEDIATE
Usual presentations:
1. Code / Arrest 2. Major trauma 3. Shock states 4. Unconscious 5. Severe Respiratory Distress
Level II Emergent
Conditions that are a potential threat to life, limb, or function, requiring rapid medical
intervention.
Time to physician assessment/interview < 15 min.
Typical presentations include: altered LOC, head injury, severe trauma, chest pain, overdose,
stroke, dyspnea, febrile neutropenia.
Level III Urgent
Conditions that could potentially progress to a serious problem, requiring emergency
intervention. May be associated with significant discomfort or affecting ability to function at
work or activities of daily living.
Time to physician < 30 min.
Presentations include: patients with moderate trauma (ex. fractures, dislocations), moderate
asthma, vaginal bleeding, suicidal patients.
Level IV Less Urgent (Semi urgent)
Conditions that related to patient age, distress, or potential for deterioration or complications
would benefit from intervention or reassurance within 1-2 hours.
Time to physician < 1 hour
Presentations include: minor head injuries, lacerations, ear ache, chronic low back pain, upper
respiratory tract infections, depression.
Level V Non Urgent
Conditions that may be acute but non-urgent as well as conditions which may be part of a
chronic problem with or without evidence of deterioration. The investigation or interventions for
some of these illnesses or injuries could be delayed or even referred to other areas of the
hospital or health care system.
Time to physician < 2 hours.
Presentations include abrasions, minor lacerations, sore throat, chronic mild abdominal pain.
The Primary Survey
Airway maintenance (w/ c-spine control)
Breathing & Ventilation
Circulation (pulses & hemorrhage control)
Disability (neurological status)
Exposure & Environment

Airway (with C-spine protection)
Assume a cervical spine injury in any pt with multi-system trauma, especially with an altered LOC or blunt injury above the clavicle. In a conscious patient, the airway is most easily assessed by patient’s ability to speak to you. Also note adventitious sounds, cyanosis, agitation, nasal flaring/indrawing in children. 1. decreased LOC 2. airway lumen: foreign body, vomit, secretions 3. airway wall: edema, fractures 4. extrinsic causes: trauma, mass, hematoma Management: Basic vs. Definitive (intubation or surgical airway) 1. chin lift or jaw thrust 2. suction to clear oropharynx 3. nasopharyngeal or oropharyngeal airway 1. unable to protect airway 2. inadequate spontaneous ventilation 3. O2 saturation < 90% with 100% O2 4. profound shock 5. GCS < 9 6. anticipate in trauma, overdose, CHF, asthma, COPD 7. anticipate in transfer of critically ill patients
Breathing
Assessed by looking, listening, and feeling… Look: anxiety / agitation, skin colour, chest movement, respiratory rate & effort
Listen: stridor, wheezing, symmetry of air entry on auscultation
Feel: tracheal shift, crepitus, flail segments, subcutaneous emphysema
o Typically 1-6 L/min, provides oxygen concentrations of 24-44% o Allows for oxygen concentration of 40-60% o Oxygen concentration >60% is possible
Circulation

control external bleeding: direct pressure, brachial/axillary/femoral pressure points immediate surgical consultation for suspected internal bleeding infusion of 1-2L RL or NS (14-16 gauge IV) type-specific: often available w/in 10 minutes o O negative used for children & women of child-bearing age o O positive for everyone else
Disability
Level of consciousness, the quick & dirty method: AVPU
o size & reactivity of pupils o movement of upper/lower extremities GCS, the not so quick and dirty method
-
reported in three parts: Eyes + Verbal + Motor = Total note that, perhaps surprisingly, a dead person still scores 3/15 (there is no 0) Verbal (5)
Motor (6)

Open spontaneously =
Incomprehensible sounds = 2 Decorticate / flexion = 3
Exposure / Environment
important to assess all areas of possible injury keep patient warm with blanket, heaters to prevent hypothermia
Then What?

The rapid primary survey is often done simultaneously with resuscitation, followed by the more detailed secondary survey, and any definitive care. ƒ Allegies
ƒ Medications
ƒ Past Medical History
ƒ Last Meal
ƒ Events related to injury
ƒ Head & Neck: pupils, LOC, facial bones, tympanic membranes ƒ Chest: breath sounds, flail segment, subcutaneous emphysema ƒ Abdomen: bowel sounds, distention, tenderness, etc. ƒ MSK: include log roll, palpation of T and L spine ƒ Neurological Exam: GCS, cranial nerves, focal deficits, papilledema An Approach to Chest Pain
Differential Diagnosis for Chest Pain

Musculoskeletal Cardiac
Pulmonary
Life-Threatening Causes of Chest Pain – consider these first: - unstable angina / acute MI - thoracic aortic dissection - pulmonary embolism - spontaneous pneumothorax / tension pneumothorax - esophageal rupture - cardiac tamponade o Position of Pain
o Quality of Pain
o Radiation: to arm, neck, jaw, back
o Severity
o Timing: including onset, as well as aggravating & alleviating factors
- Classic pain of Coronary Artery Disease: o Retrosternal pressure/heaviness o Radiating to arm/neck/jaw o Often with SOB, Nausea, Diaphoresis - Be aware of atypical presentations in: o Patients with diabetes o Elderly patients o Women o Smoking o Diabetes o HTN o Hyperlipidemia o Personal hx of CAD o Family hx of CAD Physical Exam
- Vitals, including BP in both arms - Palpate chest wall for tenderness (although a positive finding does not rule out MI, as 25% of patients with an MI have tenderness)
Investigations
o In London currently: CK, Myoglobin, Troponin o Be aware that “routine cardiac markers” vary from city to city Localization of MI based on ECG findings
ST Changes
Likely Infarct Location
Right Ventricular (often associated with Inferior)
Treatment

- Commonly used medications in MI management: o ASA 160-325mg o Oxygen o B-Blockers o Nitroglycerine o Morphine o Heparin or Low Molecular Weight Heparin (ex Enoxaparin) o Thrombolytics: ex. TPA, TNK, Streptokinase - Symptoms consistent with MI, onset within 12 hours, and - > 1mm ST elevation in 2 or more contiguous limb leads, or - >2mm ST elevation in 2 or more contiguous chest leads, or - new LBBB Thrombolysis – Absolute Contraindications - Active internal bleeding - History of CVA < 6 months, or any hemorrhagic CVA - Intracranial or intraspinous surgery or trauma < 2 months - Intracranial or intraspinous neoplasm or AVM - Suspected aortic dissection or pericarditis Thrombolysis – Relative Contraindications - Severe HTN (systolic > 200 or diastolic > 120) - Active PUD - Pregnancy - Puncture of noncompressible vessel - Significant chest trauma from CPR - Bleeding diathesis Trauma – A Brief Overview
Usually divided into blunt (ex. MVA, fall, sports injury) vs. penetrating (gunshot, stabbing). Always ask about head injury, loss of consciousness, amnesia, headache, vomiting, seizure activity.
Chest Trauma

Life threatening chest injuries
Potentially Life-Threatening Chest Injuries Contusion: pulmonary or myocardial
Hernia: traumatic diaphragmatic
Esophageal Perforation
Traumatic aortic injury / tracheobronchial disruption

Abdominal Trauma
Blunt trauma: more common; typically leads to solid organ injury Penetrating trauma: often causes hol ow organ injury Physical Exam Note that it is important to have a high clinical suspicion for abd injury in trauma, even in the absence of any immediate physical findings. - X-Ray: free air under diaphragm, diaphragmatic herniation - FAST (focused abdominal sonogram for trauma) Ultrasound o Looking for free fluid in peritoneal cavity Direct Injury
Possible Associated Injuries
Duodenum, Pancreas, Small bowel mesentery Genitourinary trauma

History:
Renal: blunt (contusions, hematomas) vs penetrating Management o if hemodynamically unstable o all penetrating wounds o renal pedicle injury rarely due to blunt or penetrating trauma extraperitoneal: typically rupture due to pelvic fracture fragments o often needs only Foley drainage unless major rupture intraperitoneal: rupture from trauma in patient with full bladder Contraindications to foley catheterization: high riding prostate on DRE in male patients
C-Spine Injuries

Assessment of a Suspected C-spine injury
o Midline neck pain o Numbness, paresthesias o Loss of consciousness o Altered mental state o Neck tenderness o Neurologic deficits o AP o Lateral C1-T1 (+ swimmer’s view if needed) o Odontoid What to look for on the lateral films? (ABCS) Alignment
o must see C1 to C7/T1 junction o assess 5 lines of contour ƒ anterior vertebral line ƒ posterior vertebral line ƒ posterior border of facets ƒ laminar fusion line ƒ posterior spinous line o including height, width, shape of vertebral bodies Cartilage
Soft Tissues
o widening of retropharyngeal or retrotracheal spaces
Defined as inadequate end-organ perfusion; ie inadequate transport of oxygen to organs and
tissues.
Classified in various different ways, including SHOCK:
o Septic & Spinal shock
o Hemorrhagic / Hypovolemic shock
o Obstructive shock (ex. tension pneumothorax, cardiac tamponade)
o Cardiogenic shock (ex. MI)
o AnaphylaKtic (so it’s not a perfect mnemonic)

In a trauma patient, assume shock is hemorrhagic unless proven otherwise.
Early:
o Incr. HR
o Incr. RR
o Narrow pulse pressure
o Decr. Urine output
o Prolonged Cap Refill
o Pale, cool extremities
Late:
o Hypotension
o Altered LOC
Replacemen
Class <15%
All patients in whom shock is suspected need: control external bleeding: direct pressure, brachial/axillary/femoral pressure points immediate surgical consultation for suspected internal bleeding infusion of 1-2L RL or NS (14-16 gauge IV) Toxicology – General Principles

ABCs of Toxicology

Airway
Breathing
Circulation
Drugs: ACLS if needed for resuscitation, universal antidotes
Draw Blood
Decontamination: if possible to decrease absorption or increase elimination
Expose / Examine
Full vitals, Foley, monitors
Give specific antidotes, treatments

Universal Antidotes
These include the following interventions with little chance of harm, but the potential for significant benefit: a necessary cofactor for glucose metabolism may be given to any pt presenting with altered LOC, though many will check chemstrip glucose at the bedside before administering Administration of naloxone may be diagnostic as well as therapeutic Adults: 2mg initial bolus IV/IM/SC/ETT (in suspected chronic opioid users, some recommend 0.1-0.4mg every 2 minutes to prevent sudden acute withdrawal) Children: 0.01mg/kg initial bolus IV/IO/ETT may need maintenance dose, as narcotics typically have longer half life than naloxone
Decontamination
Skin - removal of contaminated clothing, flushing of eyes, etc. o prevents absorption of many drugs/toxins, with the exception of acids, o 500ml (child) to 2000ml (adult) of balanced electrolyte solution by mouth o indications ƒ awake, alert patient with recent ingestion (4-6 hours) ƒ drug/toxin not bound to charcoal ƒ drug packages (body packers) ƒ suspected ileus, perforation, obstruction
Essential Bloodwork
Differential Dx for Metabolic Acidosis with increased anion gap (MUDPILES CAT) Methanol
Paraldehyde
Iron / Isoniazid
Ethylene glycol
Salicylates
Osmolar gap = Measured Osm. – Calculated Osm. Calculated Osm. Gap = 2Na + BUN + Glucose (mmol/L) Normal Osmolar Gap < 10mOsm/L Differential Dx for increased osmolar gap Methanol, Ethanol, Ethylene Glycol, Isopropyl Alcohol
Some Common Toxidromes
Toxidrome
Typical agents
Other findings
Specific
findings
interventions
Sympathomimet Cocaine
Cholinergic
Anticholinergic
Salicylates
Benzodiazepines Ativan
Serotonin
syndrome
used as an “antidote” for benzodiazepine overdose useful, in theory, as it may reduce the need for intubation in benzodiazepine overdose but, increases risk of seizure, specifically in cases of TCA co-ingestion or pre-existing seizure disorder also, most patients with a benzodiazepine overdose do well with supportive care many therefore limit the use of flumazenil to reversal of therapeutic benzodiazepine sedation in controlled settings Evaluation

Please complete at the end of your rotation and return to the Emergency Medicine office at
South Street, Room C21

1. The material in this booklet enhanced my ability to participate in the Emergency 2. The material in this booklet was relevant and useful to me during my clerkship 3. I anticipate that the material in this booklet will be useful to me during my future training – ex.during 4th year electives, residency, etc. (Please comment on sections you found particularly helpful, areas in which you’d like more information, and any additional web resources you think others would find useful.) ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________ ______________________________________________________________________________

Source: http://emlondon.ca/pdf/EmergencyMedicineClerkshipHandbook.pdf