Abdominal trauma

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Abdominal Trauma

By Beka Aberra

Outline Introduction Background Anatomy Mechanisms and Pathophysiology Clinical assessment Conclusion

INTRODUCTION Trauma is the commonest cause of death in

young people. ABDOMINAL TRAUMA STANDS THIRD NEXT

TO HEAD INJURY AND CHEST INJURY 25% of all major trauma victims require

abdominal exploration. Abdominal evaluation is the challenging

component of evaluating trauma. Penetrating torso injuries b/n nipple & perineum

is a potential intra abdominal injury. Mechanism, Force & Location of injury &

Hemodynamic status determine the priority & best method of assessment. 3

75% OF ALL BLUNT TRAUMA TO ABDOMEN INVOLVES ROAD TRAFFIC ACCIDENT

60% OF INJURY OCCUR IN MALES (14-30)

Trauma related deaths form 3 Peaks– First Peak accounts 50% die instantly or

very soon.– Second Peak accounts 30% in hours of

injury due to severe blood loss.– Third Peak accounts 20% in days to

weeks due to infection/multi organ failure.

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Anterior abdomen Flank Back Intraperitoneal space contents Retroperitoneal space contents Pelvic cavity contents

Background Anatomy

Anterior abdomen:

Trans-nipple line, Anterior axillary lines,

Inguinal ligaments and Symphysis pubis. Flank: Anterior and posterior axillary line;

Sixth intercostal to iliac crest.

Back: Posterior axillary line; Tip of scapula to

Iliac crest.

Upper Peritoneal cavityCovered by lower aspect of bony thorax. Includes Diaphragm, Liver,

Spleen, Stomach, Transverse colon.

Lower Peritoneal cavity:Small bowel Ascending and Descending colon, Sigmoid colon

Retroperitoneal space: A Potential space Behind “true” abdominal cavity

Abdominal Aorta, Inferior vena cava, Parts of Duodenum, Pancreas,

kidneys, Ureters and posterior aspects of Ascending and Descending

colons

Pelvic cavity: Rectum, Bladder, iliac vessels and Internal genitalia in women.

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The Abdomen Everything between diaphragm and

pelvis Injuries very difficult to assess

because of large variety of structures

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Abdominal Anatomy Abdomen divided into four quadrants

by body mid-line, horizontal plane through umbilicus

Organ located by quadrant

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Abdominal Anatomy Right Upper Quadrant

– Liver– Gall Bladder – Right Kidney– Ascending Colon– Transverse Colon

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Abdominal Anatomy Left Upper Quadrant

– Spleen– Stomach– Pancreas– Left Kidney– Transverse Colon– Descending Colon

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Abdominal Anatomy Right Lower Quadrant

– Ascending Colon– Appendix– Right Ovary (female)– Right Fallopian Tube (female)

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Abdominal Anatomy Left Lower Quadrant

– Descending Colon– Sigmoid colon– Left Ovary (female)– Left Fallopian Tube (female)

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Abdominal Anatomy Organs can be classified as:

– Hollow– Solid– Major vascular

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Solid Organs Liver Spleen Kidney Pancreas

When solid organs are injured, they bleed heavily

and cause shock

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Hollow Organs Stomach Gall bladder Large, small intestines Ureters, urinary bladder

Rupture causes content spillage, inflammation of

peritoneum

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Major Vascular Structures Aorta Inferior vena cava Major branches

Injury can cause severe blood loss ; exsanguination

(bleeding out)

Vascular Anatomy

1. Abdominal Aorta

2. Common Iliac Artery

3. Internal Iliac

4. External Iliac

5. Superior Gluteal

6. Obturator Artery

Can you tell me What are the top 3 most commonly

injured organs in the abdomen?

Spleen (40-55%)

Liver (35-45%)

Small bowel (5-10%)

Mechanisms Blunt trauma:Motor Vehicle Accident

Seat belt injury Penetrating injuries:Stab wounds

Gun Shot wounds Blast

Bomb Crush

Building collapse Thermal

Blunt Trauma

Motor vehicle collisions

Motorcycle collisions

Pedestrian injuries

Falls

Assault

Blast injuries

Penetrating Trauma

Stab wounds

Gun Shot wounds

Surgical Incisions

Blunt abdominal injuries carry a greater risk of morbidity and

mortality than penetrating abdominal injuries.

Mostly due to• Inadequate diagnosis• Delayed resuscitation• Delayed surgery

Blunt Abdominal trauma is the commonest cause of death in younger population with Polytrauma in RTA.

Mechanism of Injury: Blunt

Motor Vehicle Accident

Seatbelt injury

Pathophysiology 1.Compression/Concussive forces

– Direct blow

– External compression vs. fixed object (e.g. lap belt, spinal column)

Cause

• Tears & Sub capsular hematoma to solid viscera.

• Deform hollow organs & transiently Inc. intraluminal pressure.

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2. Deceleration forces– Stretching & Linear shearing b/n relatively fixed & free object.

In BAT, Organs that cant yield to impact by elastic deformation are most likely to be injured i.e. solid organs

Rapid deceleration

Shearing Force created that cause solid, visceral organs and vascular pedicles to tear at relatively fixed points of attachment. Differential movements of fixed and non-fixed structures

(e.g. liver and spleen laceration at sites of supporting ligaments) Crushing effect

B/n anterior abdominal wall and vertebral column/posterior cage

(e.g. direct blow to the epigastrium with crushing of the pancreas over the spine)

Compressive effect

Sudden dramatic rise in Intra-abdominal pressure due to external compression, hollow viscus ruptures

(e.g. direct blow to liver or blowout of the bowel)27

The most common cause of blunt trauma is the motor vehicle Injuries

Major global public health challenge but most of it occurs in low- and middle-income countries including Ethiopia.

Every year about 1.2 million people are killed and more than 20 million are injured or disabled

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Motor Vehicle Accidents

Poor road network Absence of knowledge on road traffic safety Mixed traffic flow system Poor legislation and failure of enforcement Poor conditions of vehicles; Poor emergency medical services

Traffic accident compulsory insurance law is in effect Recently.

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Contributing Factors

Seatbelt injuriesAlthough seatbelts reduce mortality overall, they cause a specific pattern of internal injuries.

Patients with seatbelt marks have been found to have a fourfold increase in thoracic trauma and an eightfold increase in intra-abdominal trauma compared with those without seatbelt marks

The three-point shoulder-lap belt is the most effective restraining system and is associated with the lowest incidence of abdominal injuries.

Use of seatbelts is thought to reduce the risk of death or serious injury for front-seat occupants by approximately 45%.

Unbelted rear-seat occupants are also at increased risk of serious injury in motor vehicle accidents (MVAs); they may be ejected or thrown forward into the back of the front seat; the impact from unbelted rear-seat passengers on front-seat occupants can be a major determinant of injury.

It is estimated that, when rear seatbelts are worn, the risk of death for belted front-seat occupants is reduced by 80%.

In direct frontal MVAs, airbags provide a reduced risk of fatality of approximately 30%.

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Compression

Of the bowel between the belt and the vertebral column, an acute short closed-loop obstruction occurs along with perforation secondary to the sudden generation of high intraluminal pressures.

Clinically, two symptom patterns emerge.

~1/4 of pt. develop evidence of a hemoperitoneum secondary to mesenteric lacerations.

In the remainder 3/4 of pt. the intestinal injury most commonly involves the jejunum contusion or perforation.

Rare cases of acute abdominal aortic dissection with incomplete or complete occlusion have also been described, and injuries to the lumbar spine are not uncommon.

Mechanism of Injury: Penetrating

Kinetic Energy imparted to body

•Low velocity: Knife Ice pick

•Medium velocity: Gunshot wounds Shotgun wounds

•High velocity: High-power hunting rifles Military weapons

Pathophysiology

Depends on the •Type of weapon•Velocity of bullet•Distance b/n assailant & victim

Typically follow the tract/trajectory of the inflicting instrument & thus involve contiguous structures.

Stab Wounds Multiple in 20% of cases

Involve the chest in up to 10% of cases

Most stab wounds do not cause an intraperitoneal injury

The incidence varies with the direction of entry into the peritoneal cavity

The liver, followed by the small bowel, is the organ most often damaged by stab wounds.

Knives are not the sole implement used in stabbings.

Ice picks, pens, coat hangers,

screwdrivers, and broken bottles.

Most commonly in the upper quadrants, the left more commonly than the right???

Gunshot Wounds

Handguns, Rifles, and Shotguns

The degree of injury depends on Amount of kinetic energy imparted by the

bullet to the victim Mass of the bullet and the square of its

velocity Distance

“crush” Bones

“stretch” Tissues

General Principles of GSW Low-velocity injury (<1000ft/sec), damage is

confined to missile tract. High-velocity injury (<2000ft/sec), blast effect

& cavitation occur in addition to damage by missile tract.

85% of ant. GSW violate the peritoneum; of these 95% require repair of intra abdominal injury.

Organs occupying the most space are more often injured

• Small bowel(29%)• Liver(28%) • Colon(23%)

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Type I wounds : long range (>7 yards) , a penetration of subcutaneous tissue and deep fascia only.

Type II wounds : distance of (3 to 7 yards) and may create a large number of perforated structures.

Type III wounds : occur at point-blank range (<3 yards) and involve a massive destruction of tissue

*1yard=0.9meter

Small bowel injury is the most common injury resulting from ___ abdominal trauma.

 penetrating blunt

Small bowel injury is the most common injury resulting from ___ abdominal trauma.

 penetrating blunt

CLINICAL ASSESSMENT

HISTORY

PHYSICAL EXAMINATION

Primary goal is to identify that an injury exists, not necessarily making an accurate diagnosis.

The patient's history may be unobtainable, elusive, or temporarily abandoned while resuscitative measures are carried out.

History from prehospital care team or transferring hospital : the vital signs, physical assessment, prehospital course, and response to therapy should be obtained

Mechanism of injury is an important factor in developing a high index of suspicion; thus a detailed history is helpful if available.

Assessment: HistoryMechanismMVC:

Speed Type of collision (Frontal, Lateral,

Sideswipe, Rear, Rollover) Vehicle intrusion into passenger

compartment Types of restraints Deployment of air bag Patient's position in vehicle Kehr’s Sign???

In blunt trauma: MVADetails about accidentFatality at the sceneVehicle type and velocityWhether the vehicle rolled overPatient's location within the vehicleExtent of intrusion into the passenger compartmentExtent of damage to the vehicleSteering wheel deformityWhether seat belts were used and, if so, what typeWhether front or side air bags were deployed

All patients involved in deceleration injuries and bicycle injuries should be suspected of having intraabdominal injury

In penetrating trauma: GSW/MSW No. of shots or stabs? Type of weapon? Number of shots heard? Position of the patient when shot? Distance of the patient from the gun? What instrument was used? How long and how wide was the instrument? How was the patient positioned during the

stabbing? What path did the implement travel?

Assessment: Physical Exam

General Examination : Relating to hemodynamic stability (Vital Signs)Abdominal findings:• Inspection :

For abdominal distension For contusions or abrasionsLap belt ecchymosis

Mesenteric, Bowel, and Lumbar spine injuries Periumblical (Cullen sign) and

Flank (Grey Turner Sign) ecchymosis – Retroperitoneal

hematoma

PHYSICAL EXAMINATION

• Palpation : For tenderness, guarding and/or rigidity, rebound tenderness – hemoperitoneum

• Percussion : Dullness/ shifting dullness Intraabdominal collection

• Auscultation : Where to auscultate & What to listen for??? All four quadrants for the +/- nce of bowel sounds

PHYSICAL EXAMINATION cont.

The classical ‘seatbelt’ sign. The bruising on the left breast is from the shoulder belt and the low bruising to the abdominal wall is from the lap belt.

Rectal findings Check for gross blood - Pelvic fracture Determine prostate position – High riding

prostate – Urethral injury Assess sphincter tone – Neurologic status Distal pulses- Assess for absence or asymmetryAssessment of other associated injuries i.e.

multiple fractures, spinal injuries etc.

PHYSICAL EXAMINATION cont..

Left lower six ribs Right lower six ribs Upper Lumbar

vertebra Transverse Process

Pelvis

Spleen

Liver

Pancreas and Duodenum

Kidneys

Bladder

Urethra

Rectum 54

Associated with fractures

Reliability of clinical evaluation

Low sensitivity Unreliable in 35/45% of pt. Why??

– Head Injury

– Spinal

– Alcohol

– Drug Repeated physical examination is

Mandatory.55

A missed abdominal injury can cause a preventable death.

Caution

The major findings with injury of the solid abdominal organs are those of hemorrhagic shock. Signs with solid organ injury include all of the following EXCEPT:

 abdominal pain and tenderness early bacterial peritonitis development of rebound, guarding and rigidity hypotension and tachycardia palpable mass and radiographic mass effect (may result from confined hemorrhage)

The major findings with injury of the solid abdominal organs are those of hemorrhagic shock. Signs with solid organ injury include all of the following EXCEPT:

 abdominal pain and tenderness early bacterial peritonitis development of rebound, guarding and rigidity hypotension and tachycardia palpable mass and radiographic mass effect (may result from confined hemorrhage)

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High Index of Suspicion Mechanism Tachycardia early, hypotension, and

pale, diaphoretic skin late Hypovolemic shock with no readily

identifiable cause Diffusely tender abdomen Pain in uninjured shoulder

Blunt Abdominal Trauma Direct impact or

movement of organs Compressive, stretching

or shearing forces Solid Organs > Blood

Loss Hollow Organs > Blood

Loss and Peritoneal Contamination

Retroperitoneal > Often asymptomatic initially

Blunt Abdominal Trauma Direct impact or

movement of organs Compressive, stretching

or shearing forces Solid Organs > Blood

Loss Hollow Organs > Blood

Loss and Peritoneal Contamination

Retroperitoneal > Often asymptomatic initially

Blunt Abdominal Trauma Direct impact or

movement of organs Compressive, stretching

or shearing forces Solid Organs > Blood

Loss Hollow Organs > Blood

Loss and Peritoneal Contamination

Retroperitoneal > Often asymptomatic initially

Blunt Abdominal Trauma Direct impact or

movement of organs Compressive, stretching

or shearing forces Solid Organs > Blood

Loss Hollow Organs > Blood

Loss and Peritoneal Contamination

Retroperitoneal > Often asymptomatic initially

Blunt Abdominal Trauma Direct impact or

movement of organs Compressive, stretching

or shearing forces Solid Organs > Blood

Loss Hollow Organs > Blood

Loss and Peritoneal Contamination

Retroperitoneal > Often asymptomatic initially

Conclusion Abdominal trauma is often difficult

to evaluate in the prehospital setting. Therefore the paramedic must exercise a high degree of suspicion based on the mechanism of injury and kinematics.

Death from abdominal injury usually results from hemorrhage and delayed surgical repair.

The KEY to Saving Lives The abdomen is the “Black Box”

– i.e, its impossible to know what specific injuries have occurred at initial evaluation.

The Key to saving lives in abdominal trauma is NOT to make an accurate diagnosis, but rather to recognize that there is an abdominal injury.

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