MCQs – Trauma 2

MCQs-trauma 2
Delayed splenic rupture can occur in 5% of splenic injuries, and begins as a subcapsular hematoma that can irritate the diaphragm and cause left shoulder tip pain.

– after the initial saline resuscitation, start with TYPE SPECIFIC blood (can get it in 10 minutes) – it is ABO compatible and Rh compatible

– the most specific test for fat embolism is a lowered platelet count. “A normal platelet count generally rules out fat embolism syndrome. An early thrombocytopenia of 100,000 RBC/cc or > 500 WBC/cc; >50,000 RBC/cc is indeterminant.

– the usual source of pelvic bleeding is venous – arterial embolization treat the 6-10% with arterial bleeding

– for pelvic trauma, urogenital injury is common. 16% bladder trauma, 7% associated urethral trauma, 6% associated genitourinary trauma with both.

– so for the wide pelvic fracture, the most common is bladder rupture

– male urethra is divided by the urogenital diaphragm into three parts:
1. the prostatic urethra between bladder and superior leaf of the urogenital diaphragm (posterior urethra)
2. the membranous urethra which traverses the urogenital diaphragm
3. the anterior urethra distal to the inferior leaf of the urogenital diaphragm

– most injuries are at the junction of membranous and prostatic urethra – characteristically the prostatic urethra tears just above the superior leaf of the urogenital diaphragm; the detachment of the prostatic urethra from the membranous urethra causes the prostate to be felt to be riding high.

– blunt trauma with a severe perineal blow (handle-bars) may crush the bulbous urethra (the first part of the anterior urethra) just below the urogenital diaphragm and rupture it.

– there may be a correlation between type of pelvic injury and urethral trauma – symphyseal disruption, bilateral pubic rami fractures, or vertical shear.

– the straddle fracture is a four pillar injury to the anterior ring, involving all four pubic rami anteriorly. Technically, it is an isolated anterior injury (Tile A2-3) with no posterior injury. Theoretically, they are caused by a direct blow, but in reality, most are lateral compression injuries and do have a posterior lesion. If you had to chose between a Malgaine type fracture versus a straddle fracture as a cause for bladder trauma, go with Malgaigne.

– bladder injury is a good indicator of overall severity of injury

– the pelvic injury that communicates with rectum needs irrigation, debridement, fixation, and diverting colostomy

– contraindication to ilioinguinal approach is the acetabular fracture with a big posterior wall fragment – you cannot see it from the inside!

– for a large posterior wall fracture with instability, you need lag