Abstracts 789

vors was 13.2 & 3.7. The average GCS for the neurologi- tally impaired survivors was 6.7 f 5.6. All patients who survived to be discharged had either a pulse or blood pres- sure in the field or ED. While the presence of vital signs in the field or ED appears to be necessary for survival, menta- tion in the field or ED appears to be necessary for survival without neurologicak impairment. They conclude that men- tal status is an important predictor of neurologic outcome In these patients. [Stewart R. Coffman, MD]

Editor’s Comment: Though mental status may predict neurologic outcome, EDT should be performed on those patients who bave vital signs in the field or electrical activ- ity in the emergency department.

0 THIGH ~~~~ART~~NT SYNDROME, A LIMB- THREATENING EMERGENCY. Martinez JF, Steingard MA, Steingard PM. Physician Sports Med. 1993;21(3):94- 104.

A case report is presented of a 17-year-old football player who sustained repeated blows to his left thigh by opponents’ helmets during a football game. While his thigh was initially painful, it became progressively more so, and after 12 hours he presented to a sports medicine clinic with a distended, firm anterior thigh with an anterior compart- ment pressure of 57 torr (normal 10-30). He was also noted to have a knee effusion and decreased range of motion at the knee. He was diagnosed with an anterior thigh com- partment syndrome and taken to surgery for fasciotomy and decompression. Compartment syndromes of the thigh are very rare due to the Iarge size of the compartment and the large size of the muscle which allows dissemination of traumatic forces. Typically, the anterior compartment is affected, and the patient presents with increasing pain in excess of physical findings: thigh distention, knee effusion and diminished range of motion in the knee. Distal pulses are usually normal, although distal sensation may be com- promised. The vessels injured in the tissue are primarily the deep perforating branches of the vastus intermedius, It is recommended that thigh circumference and compart- ment pressures be measured repeatedly and that fasciotomy be performed when pressures exceed 30 torr. Physical ther- apy is essential postoperatively, but return to athletics is reasonable in 8 to 16 weeks. [Leslie Milne, MD]

q HIST GIG DETERMINATION OF THE ISCHE- MIC THRESHOLD OF MUSCLE IN THE CANINE COMPARTMENT SYNDROME MODEL. Heckman MM, Whitesides TE, Grewe JR, Judd RL, Miller M, Law- rence JM. Grthop Trauma. 1993;7:199-210.

Two popular hypotheses regarding the critical tissue pressure in compartment syndrome at which irreversible muscle damage occurs have been proposed in the orthope- dic literature: First, that there exists an absolute maximal tolerable pressure, and alternatively that ischemia is related

to a perfusion gradient between arterial ~r~~ss~re and com- partment pressure. Sixteen conditioned dogs were anesthe- tized and compartment syndromes were created in the an- terolateral compartments of the hindleg wirh plasma infusion. Pressures were recorded cont:inuously during 8 hours of infusion. Dogs were divides into 4 groups: com- partment pressure (CP) held constant at 30 torr (in normo- tensive dogs); CP maintained to 20 torr ‘below d.iastohc blood pressure (DBP); CP 10 torr below to DBP. CP was restored to normal after 8 were monitored for 2 weeks and then ~~c~~~ice~~ Tissues were studied using light and electron microscopy for evi- dence of injury and necrosis. No s~~n~f~ca~~ ~~sto~o~ic ab- normalities were seen in tissues pressurized to a constant 30 torr. Tissues exposed to pressure 2 showed only occasional cells undergoing rege no necrosis. Tissues with CP 10 torr below scattered infarction; specimens with CP equal onstrated increased necrosis and fibrosis. The authors conclude that the perfusion gradient to muscle is more im- portant than absolute opment of irreversible ciotomy be performed torr of DBP.

Editor’s Comment: IT may prove to be more useful to think of compartment pressures in relation to the diastolic blood pressure rather in absolute terms.

0 EMERGENCY @ THE EVALUATION

vaiidity and safety of emergency center ~rteriogra~by (ECA) in children suspected injuries. During a &year per underwent evaluation with ECA. Th suspected injuries were from nique of ECA involved cannulatlng the artery, ~~rforrni~~ a single hand injection of contrast rn~t~r~a~~ single standard anteroposterior ~o~~~~e~~~r tients with firm signs of vascular injury from a single wound underwent immediate operation. They were not in- cluded in the study. Patients with firm signs of vascular injury from multiple wounds underwent ~~~e~~a~~ ECA to precisely localize the injury prior to surgery, All patients with less definite signs of vascular injury also underwent immediate ECA. The most common ~~d.~c~~~~~ for ECA was proximity (82.3% of the studies). Eighty-nine arterio- grams were interpreted as negative and 14 as positive. Gf these, there was 1 false negative and no false positives. The authors report a sensitivity of 98.9%, a specificity of J.QOVo, and a diagnost.ic accuracy of 91.2% for ECA, fig- ures which they point out compare favorably with f5~rna~ arteriography. They assert that ECA is a sensitive, safe, rapid, cost-effective, and accurate method for evaiuating