Overview

Definition:
-Splenic injury refers to damage to the spleen, a vital organ of the immune system located in the upper left quadrant of the abdomen
-It is the most commonly injured solid organ in blunt abdominal trauma.
Epidemiology:
-Splenic injuries account for approximately 45-55% of solid organ injuries in blunt abdominal trauma
-Motor vehicle accidents are the leading cause, followed by falls and assaults
-Penetrating injuries are less common but can be more severe.
Clinical Significance:
-The spleen plays a crucial role in immune defense, filtering blood, and producing lymphocytes
-Significant splenic injury can lead to life-threatening hemorrhage
-Understanding grading and appropriate management is critical for patient outcomes and avoiding unnecessary splenectomy, which increases the risk of overwhelming post-splenectomy infection (OPSI).

Clinical Presentation

Symptoms:
-Left upper quadrant abdominal pain
-Referred pain to the left shoulder (Kehr's sign)
-Abdominal distension
-Nausea and vomiting
-Signs of hypovolemic shock: tachycardia, hypotension, pallor, diaphoresis.
Signs:
-Tenderness in the left upper quadrant
-Guarding and rebound tenderness
-Palpable abdominal mass or distension
-Bruising over the left flank (Grey Turner's sign) or around the umbilicus (Cullen's sign) may indicate retroperitoneal hemorrhage, though these are late signs
-Signs of shock may be profound in significant hemorrhage.
Diagnostic Criteria:
-No specific diagnostic criteria
-Diagnosis is based on clinical suspicion in the setting of trauma and confirmed by imaging
-The American Association for the Surgery of Trauma (AAST) splenic injury scale is the most widely used grading system for classifying injury severity.

Diagnostic Approach

History Taking:
-Mechanism of injury (blunt vs
-penetrating)
-Force and direction of impact
-Speed of vehicle if MVC
-Associated injuries
-Prior abdominal surgeries or medical conditions affecting the spleen (e.g., mononucleosis, hematologic disorders)
-Medications (anticoagulants).
Physical Examination:
-Thorough abdominal examination to assess for tenderness, guarding, rebound, and distension
-Assess for signs of hypovolemic shock
-Examine the entire body for other injuries, especially chest and pelvic trauma.
Investigations:
-FAST (Focused Assessment with Sonography for Trauma) exam: rapidly detects free fluid in the abdomen, suggestive of bleeding
-CT scan with intravenous contrast: Gold standard for diagnosing and grading splenic injuries
-It identifies active extravasation of contrast (a sign of active bleeding), laceration depth, and associated injuries
-Hemoglobin and hematocrit levels, coagulation profile (PT/INR, aPTT), blood type and crossmatch
-Plain X-rays of chest and pelvis to rule out associated injuries.
Differential Diagnosis:
-Gastric perforation
-Pancreatic injury
-Renal injury
-Diaphragmatic rupture
-Rib fractures
-Left lower lobe pneumonia
-Colonic injury.

Splenic Injury Grading Aast Scale

Grade I:
-Subcapsular hematoma <10% surface area
-Intrasplenic hematoma <1cm.
Grade Ii:
-Subcapsular hematoma 10-50% surface area
-Intrasplenic hematoma 1-3cm.
Grade Iii:
-Subcapsular hematoma >50% surface area
-Intrasplenic hematoma >3cm
-Laceration depth <1cm parenchymal depth.
Grade Iv:
-Laceration with devascularization of 25-50% of spleen
-Segmental splenic artery injury.
Grade V:
-Completely shattered spleen
-Hilum vascular injury with >75% devascularization.

Management

Initial Management:
-Hemodynamic resuscitation with intravenous fluids and blood products
-Early involvement of trauma surgery
-Monitor vital signs closely
-Type and screen/crossmatch blood
-Consider early operative intervention for hemodynamically unstable patients.
Non Operative Management Nom:
-Recommended for hemodynamically stable patients with low-grade injuries (I-III) and no signs of active bleeding on CT
-Requires close monitoring in an ICU or step-down unit
-Serial abdominal examinations and hemoglobin monitoring
-Angioembolization: indicated for active bleeding (blush) on CT, particularly for higher-grade injuries (IV-V) in stable patients, to preserve splenic function
-Contraindicated in active, uncontrolled hemorrhage or hemodynamic instability.
Surgical Management:
-Splenectomy: Complete removal of the spleen
-Indicated for hemodynamically unstable patients with ongoing hemorrhage refractory to resuscitation and embolization, or for completely shattered spleen (Grade V)
-Partial Splenectomy or Splenic Repair: Reserved for specific cases, especially in children, to preserve immune function
-Techniques include debridement, suturing, and argon beam coagulation
-Less commonly performed in adults due to technical difficulty and risk of bleeding.
Supportive Care:
-Pain management
-Prophylaxis against OPSI (vaccination against encapsulated bacteria: Pneumococcus, Meningococcus, Haemophilus influenzae type b)
-Antibiotic prophylaxis post-splenectomy
-Monitoring for complications.

Complications

Early Complications:
-Hemorrhage (continued bleeding)
-Hemoperitoneum
-Hemorrhagic shock
-Injury to adjacent organs (stomach, colon, diaphragm, kidney).
Late Complications:
-Overwhelming post-splenectomy infection (OPSI): a life-threatening sepsis
-Pseudoaneurysm formation
-Splenic abscess
-Splenic cyst
-Post-traumatic stress disorder.
Prevention Strategies:
-Careful patient selection for non-operative management
-Timely angioembolization for active bleeding
-Meticulous surgical technique if splenectomy or repair is performed
-Strict adherence to OPSI prophylaxis and patient education regarding infection risks.

Prognosis

Factors Affecting Prognosis:
-Hemodynamic stability at presentation
-Severity of splenic injury (AAST grade)
-Presence of active bleeding on CT
-Associated injuries
-Timeliness and appropriateness of management
-Age and comorbidities of the patient.
Outcomes:
-Hemodynamically stable patients managed non-operatively have excellent outcomes with preservation of splenic function
-Splenectomy is associated with an increased lifetime risk of OPSI
-Outcomes are generally good with prompt and appropriate treatment, but severity of injury and associated trauma are significant determinants.
Follow Up:
-Regular clinical follow-up to monitor for complications
-Patients who have undergone splenectomy require lifelong education on OPSI prevention, including vaccination schedules and prompt medical attention for febrile illness
-For non-operatively managed patients, serial imaging may be required depending on the grade and follow-up clinical assessment.

Key Points

Exam Focus:
-AAST splenic injury grading scale is crucial
-Indications for operative vs
-non-operative management
-Role of angioembolization
-Risks and prevention of OPSI
-Management of splenic trauma in children (higher threshold for splenectomy).
Clinical Pearls:
-Always suspect splenic injury in blunt abdominal trauma, especially with left-sided thoracoabdominal impact
-Hemodynamic stability is the most important determinant for NOM
-Active contrast extravasation on CT scan is a key indicator for angioembolization or surgery
-Do not miss associated injuries in polytrauma patients.
Common Mistakes:
-Delaying definitive management in unstable patients
-Over-reliance on FAST alone for diagnosis without CT confirmation
-Inadequate monitoring of patients on NOM
-Insufficient patient education regarding OPSI risks and prophylaxis post-splenectomy.