EM Flashcards
Indications for definitive airway (4)
- Failure to maintain patent airway - obstruction, burn, angioedema, penetrating trauma, foreign body, epiglottitis, severe maxillofacial trauma
- Loss of protective reflexes - inadequate gag, lack of spontaneous swallowing, inability to handle secretions, GCS<8 (not dt rapidly reversible cause)
- Failure of adequate oxygenation/ventilation - hypoxemia unresponsive to supplemental O2, hypercapnia (may be dt ↓ resp drive, sedatives), or peripheral process (GBS, MG)
- Anticipated clinical deterioration - status epilepticus, multiple traumas +/- head injury, overdose (e.g. TCA), tiring asthmatic
6 P’s of rapid sequence intubation (RSI)
Preparation Preoxygenation - 3 min 100% NRB or 6 vital capacity breaths Pretreatment Paralysis + Induction Placement of tube Postintubation management
Medications (and doses) for RSI pretreatment (3)
Lidocaine - given with ↑ intracranial or intraocular pressure and bronchospasm; 1.5mg/kg IV
Fentanyl - mitigates tachycardic response to intubation in dissection, CAD/ 3 µg/kg IV
Atropine - consider for symptomatic bradycardia, doesn’t consistently prevent reflex bradycardia in peds; 0.02mg/kg IV
Induction medication for RSI: Etomidate
- Benefit
- Side effect
- Dose
Etomidate - Imidazole derivative
- Benefit: ↓ ICP, hemodynamically neutral
- SE: Brief myoclonus, ↓ cortisol
- Dose: 0.3mg/kg IV
Induction medication for RSI: Ketamine
- Benefit
- Side effect
- Dose
Ketamine - PCP derivative
- Benefit: Bronchodilator, dissociative amnesia, short-acting, preserves respiratory drive (awake intubation) safe in head injuries
- SE: ↑ secretions, ↑ HR, emergence phenomenon
- Dose: 1-2 mg/kg IV
Induction medication for RSI: Midazolam
- Benefit
- Side effect
- Dose
Midazolam - benzodiazepine
- Benefit: ↓ ICP, anticonvulsant effects
- Side effect: Negative inotropy → ↓ BP
- Dose: 0.1-0.2 mg/kg IV
Induction medication for RSI: Propofol
- Benefit
- Side effect
- Dose
Propofol - GABA agonist
- Benefit: ↓ ICP, ↓ airway resistance, short onset and duration of action
- Side effect: Negative inotropy, vasodilation → ↓ BP, apnea
- Dose: 1.5-3mg/kg IV
Paralytic agent for RSI: Succinylcholine
- Time to onset
- Duration
- Complications
- Dose
Succinylcholine - Depolarizing agent
- Time to onset: 45-60s
- Duration: 5-9min
- Complications: HyperK, fasiculations, trismus, ↑ ICP/IOP, malignant hyperthermia, prolonged action if ↓ pseudocholinesterase activity
- Dose: 1.5mg/kg IV
Paralytic agent for RSI: Vecuronium
- Time to onset
- Duration
- Complications
- Dose
Vecuronium - nondepolarizing agent
- Time to onset: 2-4min
- Duration: 40-60min
- Complications: prolonged action in obese/elderly/hepatorenal dysfunction
- Dose: 0.1mg/kg IV
Paralytic agent for RSI: Rocuronium
- Time to onset
- Duration
- Complications
- Dose
Rocuronium - nondepolarizing agent
- Time to onset: 1-3min
- Duration: 30-45min
- Complications: tachycardia
- Dose: 1mg/kg IV
Risks for hyperkalemia?
What paralytic agent do you avoid?
- NM disease (ALS, muscular dystrophy, myasthenia gravis)
- Skeletal muscle denervation (stroke, spinal cord injury), major burn, prolonged abdominal sepsis >5d
- Multiple trauma: from 3d to 6mo
- H/o malignant hyperthermia
** AVOID SUCCINYLCHOLINE
Salter type I
Growth disturbance?
Treatment?
Fracture extends through epiphyseal plate → displacement of epiphysis (may appear merely as widening of the radiolucent area representing growth plate)
Usually no growth disturbance
Tx: Closed reduction and immobilization
Fracture extends through epiphyseal plate → displacement of epiphysis (may appear merely as widening of the radiolucent area representing growth plate)
Usually no growth disturbance
Tx: Closed reduction and immobilization
Salter type I
Salter type II
Growth disturbance?
Treatment?
Fracture extends through epiphyseal plate, resulting in displacement of epiphysis + a triangular segment of metaphysis is fractured (Thurston Holland sign)
3/4 of all epiphyseal fractures
Usually no growth disturbance
Tx: Closed reduction and immobilization
Fracture extends through epiphyseal plate, resulting in displacement of epiphysis + a triangular segment of metaphysis is fractured (Thurston Holland sign)
3/4 of all epiphyseal fractures
Usually no growth disturbance
Tx: Closed reduction and immobilization
Salter type II
Salter type III
Growth disturbance?
Treatment?
Fracture line runs from the joint surface through epiphyseal plate and epiphysis
Involves germinal layer, therefore growth disruption is common
Tx: ORIF
Fracture line runs from the joint surface through epiphyseal plate and epiphysis
Involves germinal layer, therefore growth disruption is common
Tx: ORIF
Salter type III
Salter type IV
Growth disturbance?
Treatment?
Fracture line runs from joint surface through epiphyseal plate and epiphysis but also passes through adjacent metaphysis
Involves germinal layer, therefore growth disruption is common
Tx: ORIF
Fracture line runs from joint surface through epiphyseal plate and epiphysis but also passes through adjacent metaphysis
Involves germinal layer, therefore growth disruption is common
Tx: ORIF
Salter type IV
Salter type V
Growth disturbance?
Crush injury of the epiphysis. May be difficult to determine by radiographic examination. Suggested by mechanism of injury and pain over epiphysis. Diagnosis can be established by MRI if hemorrhage or hematoma is DI’d within the growth plate immediately after injury. Also reported is loss of MRI signal from the cartilage. Rarely diagnosed acutely.
Growth arrest is the rule, manifested by shortening or angulation.
Crush injury of the epiphysis. May be difficult to determine by radiographic examination. Suggested by mechanism of injury and pain over epiphysis. Diagnosis can be established by MRI if hemorrhage or hematoma is DI’d within the growth plate immediately after injury. Also reported is loss of MRI signal from the cartilage. Rarely diagnosed acutely.
Growth arrest is the rule, manifested by shortening or angulation.
Salter type IV
Classification of open fractures: Grade I Grade II Grade III Grade IIIA Grade IIIB Grade IIC
Classification of open fractures:
Grade I - wound <1cm long, punctured from below
Grade II - wound 5cm long, no contamination/crush, no excessive soft tissue loss/flaps/avulsion
Grade III - lg laceration + contamination/crush, frequently includes a segmental fracture
Grade IIIA - involves extensive soft tissue stripping of bone
Grade IIIB - periosteal stripping has occured
Grade IIC - major vascular injury present
Antibiotics for open fractures?
First gen cephalosporin (Cefazolin)
Add aminoglycosides if grade II or III
Amount of blood loss with radius/unla fracture?
150-250mL
Amount of blood loss with humerus fracture?
250mL
Amount of blood loss with Tib/fib fracture?
500mL
Amount of blood loss with femur fracture?
1000mL
Amount of blood loss with pelvis fracture?
1500-3000mL
Neurapraxia
Contusion of a nerve, disruption of the ability to transmit nerve pulses
Paralysis, if present, is transient, and sensory loss is slight. Normal function usually returns to a neurapraxic nerve in weeks to months.
Axonotmesis
Crush injury to a nerve, injury to the nerve within the sheath.
Schwann tubes remain in continuity, spontaneous healing is possible but slow
Neurotmesis
Severing of a nerve, usually requiring surgical repair.
Common nerve injury with distal radius fracture?
Median nerve
Common nerve injury with elbow injury?
Median or ulnar nerve
Common nerve injury with shoulder dislocation?
Axillary
Common nerve injury with sacral fracture
Cauda equina
Common nerve injury with acetabulum fracture?
Sciatic
Common nerve injury with hip dislocation?
Femoral
Common nerve injury with femoral shaft fracture?
Peroneal
Common nerve injury with knee dislocation?
Tibial or Peroneal
Common nerve injury with lateral tibial plateau fracture?
Peroneal
O’Riain wrinkle test
Tests for sympathetic nerve function – soaking normally innervated digits in warm saline for 20min → wrinkling of digital pulps through a mechanism that is not understood.
Presence of wrinkling probably indicates that nerves are intact.
Complex regional pain syndrome type 1
Pain syndrome that develops after an initiating noxious event, extends beyond the distribution of a single peripheral nerve, disproportionate to the inciting event.
Most often distal end of affected extremity, with distal-to-proximal gradient.
Associated with edema, changes in blood flow to the skin, abnormal sudomotor activity, allodynia (pain from non-noxious stimuli), hyperpathia (pain persisting or increasing after mild pressure), or hyperalgesia
Complex regional pain syndrome type 2
Pain syndrome that develops after an initiating noxious event, extends beyond the distribution of a single peripheral nerve, disproportionate to the inciting event.
Most often distal end of affected extremity, with distal-to-proximal gradient.
Associated with edema, changes in blood flow to the skin, abnormal sudomotor activity, allodynia (pain from non-noxious stimuli), hyperpathia (pain persisting or increasing after mild pressure), or hyperalgesia
+ demonstrable peripheral nerve injury
Long bone fx → restlessness, confusion, AMS, thrombocytopenia, petechial rash, respiratory distress, hypoxia
+/- fever, tachycardia, jaundice, retinal changes, renal involvement
Fat embolism syndrome.
Symptoms appear 1-2 days after acute injury or after intramedullary nailing
Fat is seen in the urine in 50% of pts w/in 3d of the injury
Incidence 0.5-2% of isolated long-bone fractures, 5-10% of pts with multiple fractures.
Supportive management, usually ICU. No specific therapy has shown benefit.
Mortality 20%, most pts recover without severe sequelae
Treatment for complex regional pain syndrome?
Multidisciplinary - PT and psychological counseling
Definitive tx - sympathetic blockade, usually with regional anesthesia and occasionally by surgical sympathectomy
Oral meds - bisphosphonates, calcitonin, indomethacin, corticosteroids, tricyclics, gabapentin, acupuncture, spinal cord stimulation, regional nerve blocks, and other meds have variable success.
Vitamin C was shown to ↓ incidence after wrist fracture in 1 study
Most common areas for fracture blisters?
What should you be worried about?
Ankle, elbow, foot, knee (in that order)
All contain fewer hair follicles and sweat glands to anchor together the epidermal-dermal junction
** believed to occur in the setting of ↑ underlying tissue pressure and may be harbinger of compartment syndrome
Vertical fracture of the neck of the talus with subtalar dislocation and backward displacement of the body.
Mechanism: forced dorsiflexion
Avaitor’s fracture
1st described in flyers during WWI. Arises from forced dorsiflexioin of the foot in flying accidents and traffic accidents after a head-on collision
Oblique intra-articular fracture of the dorsal rim of the distal radius with displacement of the carpus along with the fracture fragment.
Mechanism: high-velocity impact across the articular surface of the radiocarpal joint, with the wrist in dorsiflexion at the moment of impact.
Dorsal Barton’s fracture
Wedge-shaped articular fragment sheared off the volar surface of the radius (volar rim fracture), displaced volarly along the carpus.
Mechanism: high-velocity impact across articular surface of radiocarpal joint, with wrist in volar flexion at moment of impact.
Volar Barton’s fracture
aka reverse Barton’s fracture - much rarer than dorsal barton’s fracture
Oblique fracture through base of 1st metacarpal with dislocation of radial portion of the articular surface.
Usually produced by direct force applied to the end of the metacarpal. Dorsal capsular structures disrupted by the dislocation. Marked tenderness along medial base of thumb.
Bennett’s fracture
Fracture-dislocation of the ankle resulting in the fibula being entrapped behind the tibia.
Rare, produced by a severe external rotation force applied to the force. PE reveals foot severely externally rotated in relation to the tibia
Bosworth fracture