Does a patient shot with a lead bullet need to have it removed to avoid development of lead toxicity?

Depends.

Bullets lodged in joints should be removed because lead toxicity commonly develops as the bullet is solubilized by the acidic synovial fluid.  Bullets lodged in soft tissue however generally don't cause a problem as they are often walled off and not exposed to body fluids.  Nonetheless, if a lead bullet can be easily extracted it probably should be as there are case reports - albeit rare - of lead toxicity developing from  bullets left in non-joint spaces.


Source

Najibi, S.  et al.  "Management of Gunshot Wounds to the Joints"  Techniques in Orthopedics.  2006.

Murdock, C. et al.  "Toxic Lead Levels Treated with 2,3-Dimercaptosuccinic Acid and Surgery"  Journal of Trauma-Injury Infection & Critical Care.  1999.

Name five ways to stop a bleeding vessel on the face or scalp.

1. application of pressure DIRECTLY over the bleeding vessel
2. local infiltration with lido w/ epi 
3. suture wound closed.  often this will tamponade the bleeder. 
4. if bleeder is easily visualized and can be clamped, clamp the vessel and tie off the base with suture. 
5. bleeders that can't be easily clamped can be tamponaded by placement of a figure of eight stich

Figure of 8 stich

Source

Shah, K., Egan, D. and Quaas, J. Essentials of Trauma Surgery.  2010.

Video Source: http://www.youtube.com/watch?v=IHj6nLALvMA

How is fat embolism diagnosed?

The precise diagnosis is elusive as there is no specific confirmatory test.  The diagnosis is based on a constellation of clinical and laboratory findings (respiratory insufficiency, altered mentation, petechial rash, pyrexia, tachycardia, thrombocytopenia after long bone fracture) and exclusion of other potential diagnoses.   Patients 10 - 40 years old are most often affected.   Children younger than 10 have a lower fat content in their bones and older adults often do not sustain the major long bone fractures necessary to cause fat embolism.

Treatment is supportive care. 


Source

Akhtar, S.  "Fat Embolism"  Anesthesiology Clin.  2009.

A fall of what height (in feet) is considered a severe head injury mechanism injury in children less than 2 years? Greater than 2 years?

Less than 2 = 3 feet
Greater than 2 = 5 feet

Consider head CT in children with head injury after this mechanism of injury. For further details regarding Kuppermann's head CT decision rule for children with head trauma, click here.


Source

Kuppermann N et al. Identification of children at very low risk of clinically-important brain injuries after head trauma: A prospective cohort study. Lancet 2009 Sep 15

Fill in the blanks: Penetrating chest trauma can result in injury to abdominal structures. During expiration, diaphragmatic excursion can extend as high as the ________ anteriorly and the ________ posteriorly. Wounds below this level have the potential for injuring abdominal organs.

Penetrating chest trauma can result in injury to abdominal structures.  During expiration, diaphragmatic excursion can extend as high as the _nipple line_ anteriorly and the _inferior border of the scapula_ posteriorly.   Wounds below this level have the potential for injuring abdominal organs.


Source

Hardwood-Nuss' Clinical Practice of Emergency Medicine, 4th ed.

What is the optimal treatment for concussion?

Both physical AS WELL AS

cognitive rest until concussion symptoms have resolved at rest and with exertion.


Source

Halstead, M.  et al.  "Sport-Related Concussion in Children and Adolescents"  Pediatrics 2010.

4 month old male falls (3.5 ft) out of mother's arms onto floor hitting head. Cries immediately, small frontal hematoma, acting normal now. Head CT?

According to Kuppermann et al's recent study published in the Lancet, YES because of severe injury mechanism.

In abbreviated form:

For those metric challenged, 1.5 m = 4.92 ft and 0.9 m = 2.95 ft.


Source

Kupperman et al. "Identification of children at very low risk of clinically-important brain injuries after head trauma: a prospective cohort study" Lancet. Oct 2009.

Image source: http://www.medscape.com/viewarticle/711739

How do blast injuries cause arterial air emboli?

Two forces at play: spallation and implosion.

Spallation - takes place when a pressure wave passes from a dense medium to a less dense medium, resulting in displacement and fragmentation of the dense medium into the less dense medium. For instance, an explosive detonated under water will cause the dense water to spall into the less dense air; this is represented by an upward splash.

Implosion - takes place when gaseous contents within tissues are suddenly compressed by the blast overpressure. As the positive-pressure phase passes, the gas re-expands and releases a large amount of kinetic energy.

Arterial air emboli result from a combination of these two forces. Spalling forces disrupt the endothelium of the capillary wall as the wave enters the alveolus. The compressed gas in the alveolus (implosion) then re-expands, forcing air into the capillary - and bingo, the birth of an arterial embolus.


Source

Wolf, S. et al. "Blast Injuries" Lancet. v 374. 1 Aug 2009.

A fall from what height onto a hard surface will result in 50% chance of mortality? 90%?

50% = 48 feet (4 stories)
90% = 84 feet (7 stories)

Knowing this, check this video out: A man survives after bungee cord snaps on 400-foot dive.

While initially sounding quite impressive, the odds of this are well within plausibility. The bungee cord essentially converted a 400 foot fall into one that was only 25 feet.

Source

Marx: Rosen's Emergency Medicine, Concepts and Clinical Practice, 6th ed.

note to self: don't leave knife in patient's head

Interesting article I ran across regarding a patient's wound management experience in the ED.

This case should be a reminder that wound care is one of the most common areas of EM malpractice and that all wound discharge instructions should include a clause such as "despite thorough wound cleansing and evaluation there is still a risk of retained foreign body and infection. If you note any redness, fever, worsening pain or have any other concerns please return to the ED or see your physician immediately."

Additionally, if imaging is not part of the evaluation, the medical decision making should state the reason (as many patients and lawyers expect it although there are a million and two reasons why it is not clinically indicated).

With this charting, perhaps Shands-Jacksonville Medical Center wouldn't have made the front page of CNN ..... although there is no guarantee; but when invited to the premiere dog and pony show, court, it's probably best to have as many bows on Marley as possible.

What should be used for local anesthesia in patients with novacaine allergy?

There are two types of local anesthetics: esters and amides.

Esters: procaine, tetracaine, novacaine, cocaine. Produce metabolite PABA.

Amides: lidocaine, bupivacaine. Preserved in MPB (structurally similar to PABA).

Pure amides, without MPB preservative (dental cartridge, single-dose ampules from resuscitation cart), will not cross react with esters.

Hence, in patient with history of novacaine allergy, use lidocaine without preservative from resuscitation cart.

Source

Roberts: Clinical Procedures in Emergency Medicine, 4th ed.