Abdominal trauma

Types of abdominal trauma Abdominal injuries vary depending on the mechanism. Is the trauma blunt or penetrating? Blunt trauma: one mechanism of injury is rapid deceleration, and noncompliant organs such as liver, spleen, pancreas, and kidneys are at greater risk of injury due to parenchymal fracture. Another is crushing, where intra-abdominal content is crushed between abdominal wall and vertebral column or thoracic cage. A third mechanism of injury is external compression, where intra- abdominal pressure rises and culminate in rupture of a hollow viscous organ. Most blunt injuries are related to motor vehicle accidents. Seatbelts have reduced incidence of head, chest and solid organ injury, but may be associated with pancreatic, mesenteric, and intestinal injuries due to compression against spinal column.

Penetrating trauma Penetrating injuries that presents with shock or ongoing resuscitation require prompt exploration. Penetrating injuries of spleen, pancreas, or kidneys usually do not bleed massively unless a major vessel to the organ is damaged. Bleeding must be controlled promptly with packing and clamping for vascular control. Patients with hollow visceral injuries may have very few physical signs, but may progress to sepsis if the injuries are not recognized. When depth of injury is in doubt, local wound exploration may rule out peritoneal penetration.

Gunshot injury All gunshot wounds of the lower chest and abdomen should be explored, unless there is a likely superficial scything wound, because the incidence of injury to major intra-abdominal structures exceeds 90% in such cases. The immediate damaging effect of the bullet is typically severe bleeding, and with it the potential for hypovolemic shock. Immediate effects can result when a bullet strikes a critical organ such as the heart or damages a component of the central nervous system such as the spine or brain. All patients are qualified to laparotomy Remember to locate entry and exit wound to stop bleeding.

First aid & emergency department management When arriving at the scene of an emeergency, consider your own & the pts safty. ABC Physical examination of the abdomen History if possible Catheterization, central venous access, gastric tube, laboratory tests, etc

Imaging After physical examination, diagnostic evaluation includes bedside FAST and portable radiographs of the pelvis and chest to assess other potential sites of bleeding. If patient is unable to undergo proper FAST imaging, diagnostic peritoneal lavage (DPL) is performed. After initial FAST exam, patient should undergo abdominal and pelvic CT scan – if they are stable. If unstable and positive FAST or DPL – surgery (exploratory laparotomy)

FAST Focused Assessment with Sonography in Trauma. Ideal modality in immediate evaluation of trauma pts because it is rapid and accurate for the detection of intra- abdominal fluid or blood. Unstable pts with positive FAST examination should undergo urgent exploratory laparotomy. FAST examines four areas for free fluid: Perihepatic & hepato- renal space (also called Morison’s pouch or hepatorenal recess) Perisplenic space, Pelvic space, Pericardium (+ left and right thoracic views in eFAST)

Benefits of FAST Decreases the time to diagnosis for acute abdominal injury in blunt trauma Helps accurately diagnose hemoperitoneum Helps assess the degree of hemoperitoneum Is noninvasive Can be integrated into the primary or secondary survey and can be performed quickly, without removing patients from the clinical arena Can be repeated for serial examinations Is safe in pregnant patients and children, as it requires less radiation than CT Leads to fewer DPLs; in the proper clinical setting, can lead to fewer CT scans (patients admitted to the trauma service and to receive serial abdominal examinations)

X-ray Look for : - free air under diaphragm - elevation of diaphragm above liver – possible liver injury (hematoma) - left sided elevation of diaphragm with stomach displacement – possible spleen injury - extension of kidney shadow – possible hematoma - fracture of pelvic bones – possible bladder injury

CT Can be performed on stable pts, is a sensitive and accurate imaging technique for diagnosis of abdominal injuries. However, it is expensive, involves use of intravenous contrast administration, exposes pts to radiation, and requires experienced radiologist for interpretation.

Diagnostic surgery Basic interventions: -placement of stomach tube – stomach decompresion - urinary catheterization: blood in urine – if blood in urine possible kidney, ureter, or bladder injury – if catheterization is impossible possible urethra injury - digital rectal exam -DPL - Diagnostic laparotomy Laparotomy

DPL Diagnostic peritoneal lavage is used to detect presence of peritoneal blood. It should usually be performed through a small infraumbilical incision with placement of the catheter under direct vision. 1 L of normal saline solution is instilled into the peritoneal cavity and then allowed to drain by gravity. At least 200 mL of lavage fluid should be recovered to allow for accurate interpretation. A portion of the recovered fluid is sent for laboratory analysis of cell counts, the presence of particulate matter, and amylase. Positive: 100 000 red cells/μL, 500 white cells/μL, 175 units amylase/dL, bacteria on gram stained smear, Bile, Food particles Intermediate: pink fluid on free aspiration, 50-100 000 red cells, 100-500 white cells, 75-175 units amylase Negative: clear aspirate, <100 white cells, <75 units amylase

Diagnostic laparoscopy Important diagnostic role in patients with penetrating abdominal trauma. Can establish whether peritoneal penetration has occurred, and thus reduce the number of negative and non-therapeutic trauma laparotomies performed.

Exploratory laparotomy Indicated in almost any case of penetrating trauma. Other indications: hypovolemic shock, peritonitis signs, evisceration, gunshot wounds, free air, ongoing bleeding

liver injury The liver is voulnerable to blunt trauma due to its location and size. Liver injury poses as a high risk of shock, due to the extensive blood supply. A large majority of liver injuries can be treated nonoperatively, but this requires hemodynamic stability. Severe injury may need surgical management. The initial technique for control of hepatic hemorrhage include manual compression, perihepatic packing, and the Pringle maneuver (clamping of the hepatic pedicle). The Pringle maneuver controls all hepatic bleeding, except from hepatic veins and intrahepatic vena cava. It should not exceed one hour, in order to prevent ischemic damage of the liver.

Liver cont. Hepatic bleeding can be controlled by suture ligation, application of surgical clips directly to the bleeding vessels, or electrocautery/argon beam coagulator may be used to control bleeding from raw surfaces. Rarely, hepatic lobectomy may be required to control the bleeding.

Splenic injury The spleen is the most commonly injured organ of blunt abdominal trauma. Enlargement of the spleen (for example, due to Epstein-Barr virus causing infectious mononucleosis) makes the spleen more susceptible to injury. The primary concern in splenic injury is hemorrhage. Diagnosis is made by CT or ultrasound. In children, splenic injury is treated nonoperatively if possible. And also in 50-88% of adult blunt traumas. Angiographic embolization may be used in stable patients with high grade splenic injuries or ongoing bleeding. In the face of multiple injuries, ongoing cardiovascular compromise, or vascular avulsion of the spleen, total splenectomy is indicated. Following splenectomy, immunization against pneumococcus, meningococcus, and Haemophilus influenzae, is recommended.

Pancreatic injury Pancreatic injuries may represent with few clinical manifestations. Suspect pancreatic injury if upper abdomen has been traumatized, and if serum amylase levels are persistently elevated. Best diagnostic study (other than exploratory celiotomy) is CT scan. Minor injuries, not involving a major duct, can be treated nonoperatively. Medium injuries require operative exploration, debriment, and external drainage. Severe injuries may require distal resection and external drainage. Injuries to the pancreatic head holds a high risk in vascular injury, with high mortality rate. Late complications of injury: pseudocyst, pancreatic fistula, pancreatic abscess.

fistula

pseudocyst

stomach injury Most stomach injuries can be repaired. Large injuries may require resection. Stomach injuries are usually related to puncture wounds, and may have symptoms like: abdominal pain (first locally, then whole abdomen-peritonitis), rigid abdominal wall, tachycardia, nausea, vomiting blood.

Duodenal injury May not be evident at initial physical examination, or x-ray studies. Retroperitoneal gas will be visible on abdominal film after approximately 6 hours. most common locations of injury are duodenojejunal flexure, and the part of duodenum where pancreatic duct and common bile duct enter the duodenum. Most injuries can be treated with lateral repair. Some require resection with end-to-end anastomosis.

Polytrauma Injury to several (>1) physical regions or organ systems, where at least one injury or the combination of several injuries is life threatening with the severity of injury being > 16 on the scale of the Injury Severity Score (ISS) The Injury Severity Score (ISS) is an anatomical scoring system that provides an overall score for patients with multiple injuries. Each injury is assigned an Abbreviated Injury Scale (AIS) score and is allocated to one of six body regions (Head, Face, Chest, Abdomen, Extremities (including Pelvis), External). Only the highest AIS score in each body region is used. The 3 most severely injured body regions have their score squared and added together to produce the ISS score. To be differentiated from multiple injuries, which is not life threatening, or a severe, life-threatening single injury (barytrauma)

Example of injury severity score

sources Current diagnosis and treatment