YOU SHOT ME, YOU SHOT ME RIGHT IN THE ARM
GSWs WILL CAUSE MORE DAMAGE TO SURROUNDING TISSUE (NERVES, BONE, MUSCLE) THAN STAB INJURIES, T/F
TRUE
BLUNT VASCULAR INJURIES ARE OFTEN MORE SEVERE THAN PENETRATING INJURIES, T/F
TRUE
They are often more severe and more commonly result in amputation because of associated injuries to nerves, bone, tendons, and soft tissue.
IT IS EASIER TO PREDICT THE VASCULAR STRUCTURES INVOLVED MORE EASILY WITH STABS VS GSWs, T/F
TRUE
VASCULAR STRUCTURES AT RISK FOR INJURY ARE MORE RELIABLY PREDICTED WITH STAB WOUNDS
HOW LONG DOES IT TAKE FOR "WARM ISCHEMIA" TO SET IN?
6 HOURS
If no specific measures are taken to cool the involved extremity, the limb essentially undergoes “warm ischemia” at ambient temperature. After 6 hours of complete warm ischemia, 10% of patients will have irreversible damage; by 12 hours 90% will have irreversible damage
THIS NON-INVASIVE TEST SHOULD BE DONE IF THERE ARE ABSENT OR DIMINISHED PULSES IN AN INJURED EXTREMITY
HANDHELD DOPPLER
Arterial injury is suggested by absent Doppler signal or by a change in the usual triphasic quality of the Doppler pulse to a biphasic or monophasic waveform, because the pulse is “damped” by partial occlusion.
BLUNT INJURIES MAY CAUSE INJURY VIA DIRECT CRUSHING OR STRETCHING OF VESSELS, T/F
TRUE
SUBCLAVIAN VEIN INJURIES ARE MORE OR LESS LETHAL THAN SUBCLAVIAN ARTERY INJURIES?
MORE
More lethal than those to the artery because, in addition to massive blood loss, there is a relatively high risk of air embolism, which is frequently fatal
COOLING A LIMB TO NEAR FREEZING TEMPS CAN INCREASE TISSUE TOLERANCE TO ISCHEMIA FOR UP TO HOW LONG?
24 HOURS
Artificially cooling the limb to near-freezing temperature (“cold ischemia”) will reduce the metabolic demands and greatly prolong the tissue’s tolerance of ischemia to 24 hours or more
THIS IS A NON-INVASIVE WAY TO SCREEN FOR AN ARTERIAL INJURY
ARTERIAL PRESSURE INDEX
ANKLE-BRACHIAL INDEX
WHY IS AN OPEN AVULSION OF AN EXTREMITY WORRISOME FOR VASCULAR INJURY?
Open avulsion injury of an extremity is particularly severe because the skin, which is very pliable, is the final structure to tear. Once torn, it is inevitable that vessels and nerves will tear as well.
VASCULAR INJURIES CAN BE DIVIDED INTO WHAT 2 BROAD CATEGORIES?
OCCLUSIVE AND NONOCCLUSIVE
DESCRIBE HOW TO DO AN ARTERIAL PRESSURE INDEX
The procedure is performed as follows for an injured extremity:
COMPARTMENT SYNDROME IS MOST COMMON AFTER WHAT TYPE OF INJURY?
CRUSH INJURIES AND LONG BONE FRACTURES
INTRALUMINAL THROMBOSIS OF AN ARTERY MAY BE DELAYED FOR MONTHS AFTER INITIAL INJURY, T/F
TRUE
Intraluminal thrombosis may occur in an injured artery acutely (within 24 hours) or may be delayed for many months.
MAY BE CAUSED BY STASIS FROM ARTERIAL COMPRESSION OR INTIMA DISRUPTION LEADING TO CLOT FORMATION
WHAT IS A NORMAL VALUE FOR AN API OR ABI?
GREATER THAN OR EQUAL TO 1
In general, a ratio less than 0.90 is considered abnormal and indicates need for further investigation. In several studies, an API/ABI less than 0.90 yielded a sensitivity and specificity for the detection of vascular injury of more than 95%, with correspondingly high positive and negative predictive values. Patients with suspected vascular injury who have an API/ABI of 0.90 to 0.99 merit observation for 12 to 24 hours for repeated physical examination and API measurements to detect potentially evolving injury. Patients with normal physical examination findings and a completely normal (greater than or equal to 1.0) API/ABI can be safely discharged from the ED
NAME 2 OF THE 3 MENTIONED "NON-OCCULSIVE" INJURIES
INTIMAL FLAP
PSEUDOANEURYSM
A/V FISTULA
DOES CTA OR DUPLEX/COLOR FLOW US HAVE A HIGHER SENSITIVITY FOR DETECTING ARTERIAL INJURIES?
CTA
US HAS GOOD SENSITIVITY FOR THESE INJURIES, BUT CTA HAS HIGHER SENSITIVITY. CTA IS ALSO GOING TO BE FASTER, AND CAN VISUALIZE VESSELS THAT US CANNOT EVALUATE (VERY PROXIMAL ARTERIES)
NAME 3 "HARD SIGNS" CONCERNING FOR VASCULAR INJURY
PULSATILE HEMORRHAGE
EXPANDING HEMATOMA
ABSENT DISTAL PULSES
PALPABLE THRILL
AUDIBLE BRUIT
The incidence of arterial injury in patients with any hard finding is consistently greater than 90%, and the presence of these findings requires further investigation by emergency angiography/computed tomography angiography (CTA) or, more commonly, immediate surgical intervention, depending on the duration of warm ischemia and the overall status of the patient.
APIs ARE NOT RELIABLE WITH PROXIMAL THORACIC OUTLET INJURIES. WHY?
COLLATERAL ARTERIAL FLOW
NAME 3 "SOFT SIGNS" OF VASCULAR INJURY
SIGNIFICANT HEMORRHAGE AT SCENE
NONEXPANDING HEMATOMA
DIMINISHED PULSE OR ABI OF INJURED EXTREMITY
EXTREMITY PERIPHERAL NERVE DEFICIT
BONY INJURY OR PROXIMATE PENETRATING WOUND
The significance of prolonged capillary refill (>2 seconds) is controversial; some experts find it to be a reliable sign of vascular injury (when combined with a pulse deficit) and consider delayed capillary refill to be a valid “soft sign” of vascular injury.
HOW LONG CAN A TOURNIQUET BE SAFELY LEFT IN PLACE FOR?
6 HOURS
PENETRATING WOUNDS OCCURRING WITHIN 1 CM OF A MAJOR NEUROVASCULAR BUNDLE ARE NOT CONCERNING FOR POSSIBLE VASCULAR INJURY, T/F
FALSE
Proximity of a penetrating wound to a neurovascular bundle is defined variably as within 1 cm, 1 inch, or 5 cm. We consider penetrating wounds that occur within 1 cm of a major neurovascular bundle or whose presumed trajectory has crossed such a bundle to be sufficiently likely to produce an occult vascular injury that they warrant frequent (every 30 to 60 minutes) evaluation for the first 4 to 6 hours to ensure that a developing vascular injury is not missed within the warm ischemia window.
WHAT SHOULD YOUR TARGET SYSTOLIC PRESSURE BE IN AN ARTERIAL INJURY THAT IS NONCOMPRESSIBLE?
The target blood pressure for resuscitation should be lowered to a systolic pressure of approximately 90 mm Hg. Overly rapid fluid administration in the field or in the ED can produce transient intravascular hypervolemia and may ultimately increase the rate of blood loss.
THIS IS THE MAINSTAY OF DIAGNOSIS OF VASCULAR INJURY
Meticulous physical examination in combination with comparison of blood pressures in the affected and unaffected extremities
YOU ARE IN BFE DURING A SNOW STORM, AND IT WILL BE 9 HOURS BEFORE TRANSFER. YOU HAVE A PATIENT WITH A VASCULAR INJURY TO THEIR LEG THAT IS COMPROMISING BLOOD FLOW. WHAT CAN YOU DO THAT MAY HELP THEM UNTIL THEY CAN BE FIXED DEFINITIVELY?
COOL THE LIMB
WRAP IN TOWELS, THEN COVER WITH ICE PACKS
DISTAL PULSES CAN PERSIST DESPITE ARTERIAL INJURY, T/F
TRUE
False-negative findings can occur with transmission of the pulse through a “soft clot,” past an intimal flap, or through collateral circulation.
DO ARTERIAL INJURIES OF THE FOREARM NEED TO BE REPAIRED?
NOT NECESSARILY
Injuries to forearm vessels detected by arteriography or ultrasound do not need to be repaired unless there are signs of ischemia in the hand; “hard signs” of arterial injury, such as an expanding hematoma, a pseudoaneurysm, or an AVF; or injury to both radial and ulnar arteries. However, some authors recommend repairing all these injuries because of the risk of intermittent claudication or cold intolerance in patients who have one artery ligated. Certain patients are almost exclusively dependent on the ulnar arterial supply to the hand because of an underdeveloped deep palmar arch. This decision will be made in consultation with a vascular surgeon.