Abdullah Al-abdaliR2 EM

Outlines:

• Introduction, physics

• Anatomy

• Management– Vascular injury– Nerve injury– Compartment syndrome

• Antibiotics

Introduction

• Penetrating injury: injury produced by foreign objects that penetrate tissue.– Low energy : knife or hand-energized missiles– Medium energy: handguns– High energy: military or hunting rifles

KE= ½ mv2

Low velocity <2500 fps

High velocity >2500 fps

Temporary cavity

• Result of energy exchange b/w moving missiles & body tissue, caused by shock wave initiated by impact of the bullet.

• Diameter depends on the velocity

• The max. diameter occurs at the area of greatest resistance to the bullet.

Tissue damage can occur at some distance from the bullet track itself.

Missiles wounds

• The wound at the point of bullet impact is determined by:– Shape of the missile– Position of the missile relative to the impact site– fragmentation

Handguns Small caliber, short barrel, medium-velocity

Effective at close range

Severity of injury based upon organs damaged

Rifle High-velocity, longer barrel, large caliber

Increased accuracy at far distances

Assault Rifles Large magazine, semi- or full-automatic

Similar injury to hunting rifles

Multiple wounds

Handguns Small caliber, short barrel, medium-velocity

Effective at close range

Severity of injury based upon organs damaged

Rifle High-velocity, longer barrel, large caliber

Increased accuracy at far distances

Assault Rifles Large magazine, semi- or full-automatic

Similar injury to hunting rifles

Multiple wounds

Specific Weapon Specific Weapon CharacteristicsCharacteristics

Handguns Small caliber, short barrel, medium-velocity

Effective at close range

Severity of injury based upon organs damaged

Rifle High-velocity, longer barrel, large caliber

Increased accuracy at far distances

Assault Rifles Large magazine, semi- or full-automatic

Similar injury to hunting rifles

Multiple wounds

Handguns Small caliber, short barrel, medium-velocity

Effective at close range

Severity of injury based upon organs damaged

Rifle High-velocity, longer barrel, large caliber

Increased accuracy at far distances

Assault Rifles Large magazine, semi- or full-automatic

Similar injury to hunting rifles

Multiple wounds

Specific Weapon Specific Weapon CharacteristicsCharacteristics

Anatomy

• 2 guiding principles:– The major nerves tend to follow the course of

major arteries. Ex.

– Most of extremity musculature is organized into compartments, which encased by unyielding fibrous fascia.

• A 19 yrs old male, was struck in the R. thigh by stray bullet, he collapsed. In ED, looks pale, P:120, BP:100/50, RR:22, O2 sat:95% on 100% O2,on 10 survey, he is alert & without trauma to the head, neck or chest. Had clear breath sound b/l. on 2nd survey he had, normal cardiac & abdomen Exam. You found an entrance wound on his proximal thigh (just distal to inguinal lig.) which is oozing blood, he has no back wound, he has a sizable R. thigh hematoma, but there is no pulsating blood coming from the wound, EMS said it is same for the last 20min. His R. DP pulse is present.

What Do you want to Do first:• Take him to OR• Obtain pelvis and leg x-ray and perform FAST exam.• Intubate the patient• Measure compartment pressure

Management

Go straight to where the money is

1o survey

A

B

C

E

D

Extremity Injuries are examinedduring the 2nd survey, once

patient stabilized

• Purpose of the exam:

Has there been an injury to a Major artery or vein?

Is there any evidence of bone or tendon injury?

Has a peripheral nerve been transected?

Is there any evidence of compartment syndrome?

What to examine?

• Pulse: compare it with uninjured extremity.• Hand held Doppler• API• Color• Coolness• Sensation• Tendons • Pain

Careful physical exam

and high index of suspicion are most

important !

Hand held Doppler

• Determine presence/absence of arterial supply

• Assess adequacy of

flow

PRESENCE OF SIGNAL DOES NOT EXCLUDE ARTERIAL INJURY !

API

• Ratio of 0.9 or less, abnormal• 0.9 to 0.99 observe for 12-24Hs

• sens: 45-95% for wounds requiring OR

SBP is obtained by inflating a blood pressure cuff proximal to the injury, and using the Doppler distal to the injury to determine the SBP

Vascular injury

• 3 Qs.– When dose the Pt need to go to OR?– When dose the Pt need angiography?– When can the Pt simply observed and

discharge home?

Extremity Wound

Open Wound (larger lacerations):-can bleed profusely.**1st step is to stop bleeding.•Direct pressure•Tourniquet•Don’t ligate blindly.

Penetrating wound:-Small wound-external bleed is minimal

Doesn't exclude significant arterial injury.

HARD SIGNS OFARTERIAL INJURY

Hard Vs Soft signs:

HARD SIGNS:• Pulsatile bleeding• Expanding or pulsatile

hematoma• Palpable thrill or

audible bruit• Ischemia 5P’s

SOFT SIGNS:• Large non-pulsatile

hematoma• Isolated nerve injury• Proximity injury • Palpable, but

diminished pulse

• The incidence of arterial injury in the presence of any one of hard signs is >90%.

• 35% of patients with soft finding had positive angiographic studies.

• Vascular injury occurs in 8-45% of cases of penetrating nerve injury.

Diagnostic strategies

• Non

• X-ray

• Ultrasound

• Arteriography

• CTA

X-ray:

• Detect fracture

• Joint penetration

• Foreign bodies– The position of metallic bodies– The presence of fragments of a bullet which

has broken up.

Ultrasound

• Duplex US (B-mode + US)

• Non-invasive, portable

• Sn 83 – 100%

• Sp 99 – 100%

• Operator dependent

• Not always 24 h available.

Arteriography

• It has been the gold standard for Dx.– Sens: 98%– Spec: 99%

• Problems:– The cost– Need to leave the ED– Small complication of arterial cannulation– Difficult in children.– 5% FP, 5% FN when compare to surgical exploration

CTA

• Less invasive

• Much more readily available

• Less time consuming

• Replacing angiography in many indications.

CT angiography effectively evaluates extremity vascular trauma.Peng PD, Spain DA, Tataria M, Hellinger JC, Rubin GD, Brundage SI.

This study supports CTA as an effective alternative to Conventional arteriography in assessing extremity vascular trauma.

Am Surg. 2008 Feb;74(2):103-7. Division of Trauma and Surgical Critical Care, Department of Surgery, Stanford University Medical Center, Stanford, California, USA

CONCLUSIONS: With acceptable injury detection, rapid availability, and a favorable cost profile, our results suggest that CTA may replace arteriography as the diagnostic study of choice for vascular injuries of the extremities.

J Trauma. 2009 Aug;67(2):238-43; discussion 243-4.

OR

Injury type

• ED exploration• Irrigate thoroughly- Primary closure- Tetanus

• observe, irrigate, tetanus•X-ray for GSW•Consider AP/US•Consider CTA/angio•Loose closure for SW

vascular studyfirst if woundlocation unclear

OR

CTA/arterio

CTA/arterio

Shotgunsharpnel

openlaceration

Arterial injury

OR+

+ AP/US

+

Manage ABCs

Axillary orInguinalWound?

CTA/arterio HardSigns

PresentOR

+

Yes NO

Yes NO

simple SW or GSW

Manage ABCs

Axillary orInguinalWound?

CTA/arterio HardSigns

Present

Injury type

• ED exploration• Irrigate thoroughly- Primary closure- Tetanus

• observe, irrigate, tetanus•X-ray for GSW•Consider AP/US•Consider CTA/angio•Loose closure for SW

vascular studyfirst if woundlocation unclear

OR+

OR

CTA/arterio

CTA/arterio

Yes NO

OR

Shotgunsharpnel

openlaceration

Arterial injury

OR+

+ AP/US

+

Yes NO

simple SW or GSW

+

GSWindication for OR

– Hard signs

– Progressive neuro deficit

– Open fracture

– Unstable fracture

– Significant soft tissue damage or necrosis

– Compartment syndrome

Blood loss

Ischemia

Compartment

syndrome

Tissue necrosis

Amputation

Death

Complications

Nerve injury

• Difficult to asses in trauma patient.• Neuropraxia

– Contusion of the nerve– Normal function returns in weeks to months

• Axonotmesis– Injury to nerve fibers occurs within their sheath.– Spontaneous healing is possible but slow? Why?

• Neurotmesis– Is the severing of nerve– Usually require surgical repair

Examination

• Examine sensation and muscle power

• Two-points discrimination is a more sensitive examination.

• Testing for sympathetic nerve function using the O’Riain wrinkle test may be helpful.

Compartment syndrome

• It is a complication of arterial or venous injury.

• A rise in pressure with a compartmentalized group of tissues leading to impaired perfusion, ischemia and necrosis of muscles within the compartment.

Pathophysiology

• Increased compartment contents

• Decrease compartment volume

• External pressure

Clinical presentation

• Pain that is disproportionate to the injury.

• Pain is deep, burning and difficult to localized.

• Pain on passive stretching of the muscle groups.

• Hypoesthesias & paresthesias

Diagnosis & treatment

•Capillary blood flow becomes compromised at 20 mmHg. •Pain develops at pressures between 20 and 30 mmHg. •Ischemia occurs at pressures above 30 mmHg.

Fasciotomy to fully decompress all involved compartments is the definitive treatment for ACS in the great majority of cases

Antibiotics

• Pt going to OR broad spectrum IV antibiotics• Hand & Foot & high velocity short course antibiotics

with one dose IV.• Other site single IV dose to cover skin flora.• For immunocompromised patient.

J Am Acad Orthop Surg, Vol 14, No 10, September 2006, S98-S100. © 2006 the American Academy of Orthopaedic Surgeons

Schmidt et al, Chemotherapy 2002;45: 1621-1626

195 patients

ceftriaxon cefoxitin

TID x3 days

There was no significant different in the infection rate and no patientDeveloped deep tissue infection requiring surgical intervention by Post-trauma day 10

• While you are waiting for the result of x-rays, he becomes tachypneic, and BP drops to 70/40 with P:160, oxygen sat. probe is not picking up a reading. A repeat 1o survey reveals an intact airway & clear breath sounds & his thigh looks the same, you look at the back & axilla again to assure you didn’t miss any injury:

What is a possible explanation for his deterioration?

• Occult Pneumothorax that has become a tension Pneumothorax.

• Anemia from ongoing occult bleeding

• Fat embolism from a femur fracture

• Missile embolism to the pulmonary vasculature.

Missile embolism

• The travel of foreign bodies from penetrating trauma through blood stream.

• Can be arterial or venous:– Arterial: distal obstruction & distal ischemia– Venous: travel through R. heart to P. arterial system PE

• Arterial emboli can be removed either with arteriotomy or balloon catheter embolectomy.

• All centrally located, symptomatic venous emboli, need to be removed.

• Some surgeon will leave asymptomatic missiles in place, which has been shown to be safe.

Tetanus

Summary • ATLS

• Indication for OR? Stable /

unstable?

• Further investigations?

• Don’t miss nerve injury

• Compartment syndrome

• Antibiotics?

• Tetanus

Compartments of the lower leg

• Anterior compartment- most frequently affected

– Muscles- tibialis anterior, extensors of the toes (EHL and EDL)

– Test: Extension of the 1st toe– Nerves- Deep peroneal nerve– Test: Web space of 1st toe– Vascular- Anterior tibial artery– Test: Dorsalis pedis pulse

• Lateral Compartment– Muscles- Preens longus and

brevis– Test: Foot eversion– Nerves: Superficial peroneal

nerve– Test: Dorsum of foot– No artery

• Deep Posterior Compartment– Muscles: tibialis posterior, the

flexor digitorum longus & FHL– Test: Toe flexion– Nerves: Tibial nerve– Test: Sole of foot (heel too)– Vascular: Posterior tibial artery– Test: Posterior tibial pulse

• Superficial Posterior compartment

– Muscles: Gastrocnemius and, the soleus muscle

– Test: Plantar flexion– Nerve: Sural nerve.– Test: Lateral aspect of 5th toe