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COMPREHENSIVE SURGICAL EXAM ANSWERS

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Q1. Traumatic Diaphragmatic Hernia (Run-over Injury, Bowel Loops in Left Hemithorax)

Diagnosis [2]

• Respiratory distress (lung compression)
• Shock (strangulation, hemorrhage, mediastinal shift)
• CXR showing air-fluid levels in left hemithorax with absent/elevated left diaphragm

Investigations [3]

1. Chest X-ray - Air-fluid levels in left hemithorax, mediastinal shift to right, absent diaphragmatic contour (already done)
2. CT scan chest/abdomen - Gold standard; confirms diaphragm defect, identifies herniated organs, associated injuries (spleen, liver, aorta)
3. Nasogastric tube - If tip visible in chest on CXR = diagnostic of stomach herniation
4. FAST (Focused Assessment with Sonography in Trauma) - Assess for hemopneumothorax, pericardial effusion
5. Diagnostic peritoneal lavage (DPL) - If CT unavailable
6. Upper GI contrast study - Barium/gastrografin if diagnosis uncertain
7. Bloods - FBC, U&E, coagulation, cross-match, ABG (metabolic acidosis in shock)

Management [5]

• A - Airway: Intubate if respiratory distress severe (avoid bag-mask if bowel in chest)
• B - Breathing: No needle thoracocentesis (risk of bowel perforation); supplemental O2
• C - Circulation: 2 large-bore IV lines, crystalloid/blood transfusion, monitor BP/HR
• D - Disability: GCS, pupils
• E - Exposure: Full secondary survey

• Urgent surgery once resuscitated (within hours)
• Approach:
  • Laparotomy preferred acutely (allows repair + assessment of all abdominal injuries)
  • Thoracotomy if massive hemorrhage from chest or if laparotomy fails adequate repair
• Steps:
  1. Reduce herniated contents back into abdomen
  2. Assess bowel viability - resect if ischemic
  3. Repair diaphragm with non-absorbable interrupted sutures (polypropylene) or mesh if large defect
  4. Assess and manage associated injuries (spleen, bowel, mesentery, retroperitoneum)
  5. Chest drain insertion after closure
• Delayed presentation: Laparoscopic repair possible; elective approach

• ICU care, ventilatory support, NG decompression
• Antibiotics (if bowel contamination)
• DVT prophylaxis

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Q2. Penetrating Neck Injury (Knife in Posterior Triangle of Neck)

Surgical Anatomy Relevant to Penetrating Neck Injury [2]

Evaluation [3]

• Active arterial bleeding, expanding/pulsatile hematoma
• Airway compromise (stridor, dysphonia, subcutaneous emphysema)
• Neurological deficit (stroke, hemiplegia)
• Hematemesis/hemoptysis

• Stable hematoma, dysphagia, dysphonia, Horner's syndrome, subcutaneous air

1. CXR - Hemothorax, pneumothorax, widened mediastinum
2. CT Angiography of neck/chest - Investigation of choice; evaluates vascular, airway, esophageal injury
3. Rigid esophagoscopy / contrast swallow - Esophageal injury
4. Flexible bronchoscopy - Tracheal/bronchial injury
5. Doppler ultrasound - Carotid/jugular assessment
6. Angiography - Gold standard for vascular injury; also therapeutic

Management [5]

• Airway: Early intubation (can become difficult with expanding hematoma); surgical airway if necessary (tracheostomy/cricothyrotomy); do not remove knife
• C-spine immobilization (if mechanism suggests)
• Two large-bore IV lines, fluid resuscitation, cross-match blood
• Direct pressure to control hemorrhage (not blind clamping)

• Mandatory exploration if hard signs present (Zone II - most accessible)
• Selective conservative management with imaging for stable Zone I/III injuries
• For Zone I injuries: sternotomy or thoracotomy may be needed for proximal vessel control
• For Zone III: difficult access; endovascular approaches preferred

1. Incision along anterior border of sternocleidomastoid
2. Identify and repair/ligate injured vessels (primary repair > ligation for carotid; ligature acceptable for EJV)
3. Esophageal repair in 2 layers with drain
4. Tracheal repair with absorbable sutures ± temporary tracheostomy
5. Drain the wound
6. Post-op ICU monitoring

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Q3. Mechanism of Penetrating Injuries Caused by Firearms [5]

1. Laceration and Crushing

• Direct injury by the bullet along its track
• Proportional to caliber (diameter) of bullet
• Creates a permanent cavity = actual tissue destroyed

2. Cavitation (Temporary Cavity)

• As a high-velocity bullet passes, kinetic energy is transferred radially outward
• Tissues are momentarily displaced outward (cavitation), then recoil back
• The temporary cavity can be 30-40x the bullet diameter for high-velocity rounds
• Causes "stretch injury" - tearing of blood vessels, nerves even outside the direct track
• High-velocity weapons (rifles, military weapons, velocity >600 m/s) cause large temporary cavities; low-velocity (handguns, <600 m/s) cause minimal cavitation

3. Shock Wave / Blast Effect

• A pressure wave precedes the bullet
• Significant only at very high velocities
• Causes tissue disruption ahead of bullet path

Additional Factors:

• Bullets yaw (deviate from longitudinal axis) and tumble on entering tissue
• Maximum energy transfer when bullet is sideways (90°) to direction of travel
• Tumbling dramatically increases the volume of tissue destroyed

• Some bullets fragment on impact (dum-dum, hollow-point)
• Multiple fragments create multiple wound tracks = greater destruction

• Velocity is the most important determinant (squared relationship)
• Doubling velocity quadruples energy transferred

• Entry wound: Small, may be inverted (tattooing, burning if close-range)
• Exit wound: Larger, ragged, everted (no burning/tattooing)
• Wound track: Primary track + zone of hemorrhage + zone of contusion

• Fluid-filled structures (bladder, bowel) transmit pressure waves and burst
• Liver/spleen: inelastic, shatter easily
• Lung: elastic, tolerates cavitation better
• Bone: shatters, creates secondary missiles

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Q4. Primary Survey in Polytrauma + Airway Obstruction after Facio-maxillary Trauma [4+6]

Components of Primary Survey (ABCDE) [4]

1. A - Airway (with C-spine control)
   • Assess patency, look/listen/feel
   • C-spine immobilization (hard collar + blocks + tape = triple immobilization)
   • Chin-lift/jaw-thrust, suction, oropharyngeal airway
2. B - Breathing and Ventilation
   • Inspect, palpate, percuss, auscultate
   • Look for: tension pneumothorax, open pneumothorax, massive hemothorax, flail chest
   • Administer high-flow O2 (15L/min via non-rebreather mask)
3. C - Circulation with Hemorrhage Control
   • Pulse, BP, capillary refill, skin color
   • External hemorrhage: direct pressure
   • 2 large-bore IV lines, warm crystalloid (Hartmann's/NS) 1-2L bolus
   • Transfusion if unresponsive (MTP - massive transfusion protocol)
   • FAST scan for occult hemorrhage
4. D - Disability (Neurological Status)
   • GCS (Eye 4, Verbal 5, Motor 6)
   • Pupils: size, reactivity, asymmetry
   • Blood glucose (hypoglycemia can mimic head injury)
5. E - Exposure/Environment
   • Completely undress the patient
   • Logroll for back/spine assessment
   • Cover with warm blanket (prevent hypothermia)

Management of Acute Airway Obstruction after Facio-maxillary Trauma [6]

• Blood clots, teeth, bone fragments in oropharynx
• Tongue falling back (mandibular fracture)
• Edema of soft tissues
• Hematoma in floor of mouth
• Retropharyngeal hematoma
• Laryngotracheal injury

• Suction oropharynx (Yankauer catheter) - remove blood, secretions, foreign bodies
• Chin-lift or jaw-thrust (avoid neck extension if C-spine injury suspected)
• Remove broken dentures, avulsed teeth, bone fragments manually
• Position: sitting forward if possible (allows drainage)

• High-flow O2 via non-rebreather mask
• Pulse oximetry monitoring

• Oropharyngeal airway (Guedel) if unconscious
• Nasopharyngeal airway if conscious (use cautiously if base of skull fracture suspected - absent in facio-maxillary trauma)

• Orotracheal intubation (RSI with in-line C-spine stabilization) if mouth opening allows
• Blind nasotracheal intubation (spontaneously breathing patient, no base-of-skull fracture)
• Video-laryngoscopy - preferred if anticipated difficult airway
• Awake fiber-optic intubation - gold standard for anticipated difficult airway (cooperative patient, edema/hematoma)

• Emergency Cricothyrotomy - fastest surgical airway
  • Needle cricothyrotomy (immediate, buys ~30 min) then convert to:
  • Surgical cricothyrotomy: vertical skin incision, horizontal cricothyroid membrane incision, insert small cuffed ETT (6.0)
• Tracheostomy - elective, more controlled, preferred if prolonged airway management needed (e.g., panfacial fractures)

• Secure airway with ties/tape
• CXR to confirm tube position
• Monitor SpO2, ETCO2
• Refer to maxillofacial surgery for definitive fracture fixation (intermaxillary fixation, ORIF)

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Q5. Head Injury

a) Pathophysiology of Head Injury

• Focal (contusion, laceration, extradural/subdural/intracerebral hematoma)
• Diffuse (diffuse axonal injury - DAI from acceleration-deceleration)

CPP = MAP - ICP (normal ICP = 5-15 mmHg; target CPP ≥60 mmHg)

1. Raised ICP - Progressive herniation (uncal, transtentorial, tonsillar)
2. Cerebral ischemia - Hypotension (SBP <90 = catastrophic), hypoxia (PO2 <60 mmHg)
3. Cerebral edema - Vasogenic (BBB disruption) or cytotoxic (cell swelling)
4. Excitotoxicity - Glutamate release, calcium influx, free radical damage
5. Coagulopathy - DIC, platelet dysfunction
6. Vasospasm - Especially after SAH
7. Metabolic - Hypoglycemia, hyperglycemia, hyponatremia, fever

• Uncal herniation: ipsilateral CN III palsy (blown pupil), contralateral hemiplegia, Cushing's response (hypertension + bradycardia + irregular breathing)

b) Surgical Management of Raised ICP

1. Head of bed 30°, neutral head position
2. Osmotherapy: Mannitol 20% (0.25-1 g/kg IV bolus) or 3% hypertonic saline
3. Controlled ventilation: target PaCO2 35-40 mmHg (hyperventilation: PaCO2 30-35 as bridge only)
4. Sedation/analgesia: propofol, fentanyl (reduces ICP)
5. Temperature control: normothermia (hyperthermia worsens injury)
6. Treat seizures: levetiracetam, phenytoin
7. Glucose control: maintain 6-10 mmol/L

1. Burr hole evacuation:
   • Emergency (life-saving) for extradural hematoma with rapid deterioration
   • Temporal burr hole (pterional) for EDH
   • Frontal/parietal for acute SDH
2. Craniotomy:
   • For EDH: evacuation + hemostasis (middle meningeal artery ligation)
   • For acute SDH: evacuation, brain decompression
   • For depressed skull fracture: elevation, debridement
   • Indications: EDH >30 mL, SDH >10mm thick or >5mm midline shift
3. Decompressive Craniectomy (DC):
   • Remove a large bone flap (unilateral or bifrontal) to allow brain swelling externally
   • Indicated when ICP refractory to all medical treatment
   • DECRA and RESCUEicp trials: reduces ICP but outcomes debated
   • Complications: "syndrome of the trephined," herniation through defect
4. CSF drainage:
   • External ventricular drain (EVD) placed via Kocher's point
   • Drains CSF, also monitors ICP continuously
5. ICP monitoring:
   • Ventriculostomy (gold standard): measures + drains CSF
   • Intraparenchymal bolt (Camino): measures only
   • Indications: GCS ≤8 with CT abnormality, or GCS ≤8 with normal CT + 2 of: age >40, decerebrate posturing, SBP <90

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Q6. Hospital Management of RTA with Blunt Abdominal Injury and Shock

• Airway: intubate if GCS <8 or respiratory distress
• Breathing: supplemental O2, chest drain if pneumo/hemothorax
• Circulation: 2 large-bore IV (antecubital), send bloods (FBC, U&E, LFTs, amylase, coagulation, ABG, cross-match 6 units), fluid resuscitation (warm Hartmann's 1-2L; if no response = activate massive transfusion protocol - pRBC:FFP:platelets = 1:1:1), Foley catheter (monitor UO), FAST scan

• Free fluid in abdomen = urgent laparotomy if hemodynamically unstable
• Positive FAST + stable = CT scan (MDCT abdomen/pelvis with contrast)

• CT abdomen/pelvis with IV contrast = gold standard in stable patients
  • Grades injuries (liver, spleen, kidney, pancreas, mesentery)
  • Identifies extravasation of contrast ("blush" = active hemorrhage)
  • Identifies free air (hollow viscus perforation)

1. Damage Control Laparotomy (DCL): control hemorrhage + contamination only
   • Pack liver/spleen/retroperitoneum
   • Clamp/staple bowel - no anastomosis
   • Temporary abdominal closure (Bogota bag)
2. Resuscitate in ICU (correct hypothermia, coagulopathy, acidosis - "lethal triad")
3. Re-look laparotomy at 48-72 hrs: definitive repair/anastomosis

• Stable hemodynamics + no hollow viscus injury
• Spleen Grade I-III, Liver Grade I-III: bed rest, serial examination, serial Hb, repeat imaging
• Angioembolization: for active contrast blush on CT (Spleen Grade III-IV, Liver Grade III-IV)
• Failure criteria: worsening vital signs, increasing transfusion requirement = laparotomy

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Q7. Compartment Syndrome

a) Pathophysiology

• Increased compartment contents: fracture hematoma, reperfusion edema, crush injury, burns, envenomation, extravasation of IV fluids
• External compression: tight cast, constrictive dressing, prolonged immobilization

1. Precipitating injury → hemorrhage/edema within compartment
2. Tissue pressure rises → venous outflow obstructed
3. Arteriovenous gradient falls → local ischemia
4. Ischemia → capillary permeability increases → more edema
5. Vicious cycle of increasing pressure
6. At >30 mmHg: muscle/nerve ischemia begins
7. At 6 hrs: irreversible muscle necrosis (rhabdomyolysis → myoglobinuria → renal failure)
8. At 12-24 hrs: irreversible nerve damage → Volkmann's ischemic contracture

b) Investigation and Management of Compartment Syndrome of Lower Limb

1. Clinical diagnosis is primary (do not wait for investigations)
2. Compartment pressure measurement:
   • Stryker STIC device or improvised saline manometer
   • Measure all compartments (leg has 4: anterior, lateral, deep posterior, superficial posterior)
   • Threshold: absolute pressure >30 mmHg OR delta-P (diastolic BP - compartment pressure) <30 mmHg
3. Investigations to assess damage:
   • Serum CK (markedly elevated)
   • Urine myoglobin (cola-colored urine)
   • Renal function (acute tubular necrosis)
   • Serum K+ (hyperkalemia from rhabdomyolysis)

1. Remove all circumferential dressings/splints/casts
2. Position limb at heart level (not elevated - reduces perfusion)
3. Supplemental O2
4. Optimize blood pressure
5. IV fluid resuscitation

• Perform within 6 hours of onset
• All 4 compartments of the leg must be released

• Lateral incision (fibula): releases anterior + lateral compartments
  • Anterior: tibialis anterior, EHL, EDB, deep peroneal nerve, anterior tibial vessels
  • Lateral: peroneus longus/brevis, superficial peroneal nerve
• Medial incision (4 cm behind tibia): releases deep + superficial posterior compartments
  • Superficial posterior: gastrocnemius, soleus
  • Deep posterior: FDL, FHL, TP, posterior tibial vessels, tibial nerve

• Wounds left open, covered with saline-soaked gauze or vacuum dressing (VAC)
• Re-look at 48-72 hours
• Delayed primary closure or split-thickness skin graft (STSG) if cannot close primarily
• Assess muscle viability: viable = pink, contracts on stimulation, bleeds; non-viable = excise

• Volkmann's ischemic contracture (equinus deformity of foot)
• Myoglobinuric renal failure
• Hyperkalemia → cardiac arrest
• Sepsis, gas gangrene

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Q8. Pelvic Fracture

a) Clinical Assessment [Assessment]

• Compression test: hands on iliac crests, compress medially (unstable = pain/movement)
• Distraction test: hands on ASISs, push laterally
• Vertical shear: push/pull leg axially (Perform only ONCE - repeated examination worsens bleeding)

• Deformity, shortening, external rotation of lower limb
• Pelvic ecchymosis (Destot's sign = inguinal/scrotal hematoma)
• Perineal laceration (open fracture)
• Blood at urethral meatus (urethral injury)
• High-riding prostate on PR (urethral rupture)
• Rectal blood (rectal injury)
• Neurological: L4/L5/S1 nerve root injury (foot drop, perineal numbness)

• Type A: stable (pubic rami fractures)
• Type B: rotationally unstable, vertically stable (open/closed book)
• Type C: rotationally and vertically unstable (vertical shear)

b) Associated Injuries

1. Urological: Bladder (extraperitoneal > intraperitoneal rupture), Posterior urethral injury (membranous urethra), kidney injury
2. Vascular: Iliac vessel injury (major cause of mortality), superior gluteal artery, internal pudendal artery, presacral venous plexus (retroperitoneal hematoma)
3. Neurological: Lumbosacral plexus, sciatic nerve, pudendal nerve
4. Gastrointestinal: Rectal/anal injury (open pelvic fracture)
5. Gynecological: Vaginal laceration, uterine injury
6. Skin: Morel-Lavallee lesion (degloving between fascia and skin over greater trochanter)
7. Associated fractures: Acetabulum, femur, lumbar spine

c) Management of Hemorrhage in Pelvic Fracture

• Venous (presacral/pelvic venous plexus) - 85%
• Arterial (internal iliac branches) - 15%
• Bone surfaces

1. Pelvic binder (wrap at level of greater trochanters) or bed sheet - first responder intervention
   • Closes the "open book" fracture, reduces pelvic volume, tamponades venous bleeding
   • Do NOT use in lateral compression fractures
2. Resuscitation: MTP activation (1:1:1 pRBC:FFP:platelets), TXA (tranexamic acid 1g within 3 hours), permissive hypotension (SBP 80-90 mmHg until hemorrhage control)
3. External fixator (Ex-fix):
   • Frame fixation of pelvis (anterior pins into iliac crest)
   • Reduces pelvic volume and stabilizes fracture
   • Good for anterior ring injuries (pubic symphysis diastasis)
4. Preperitoneal pelvic packing (PPP):
   • Incision below umbilicus, pack preperitoneal space (space of Retzius) with 3 packs
   • Effective for venous (90% of pelvic hemorrhage is venous) and bony bleeding
   • Combined with external fixation
   • Preferred in hemodynamically unstable patients in centers without 24-hr angiography
5. Angiography and embolization:
   • For arterial hemorrhage (contrast blush on CT, continued hemorrhage after packing)
   • Selective embolization of internal iliac branches (anterior division, superior gluteal, internal pudendal)
   • Can be performed in hemodynamically stable/temporarily stabilized patients
   • Complication: gluteal necrosis, erectile dysfunction, neurological injury
6. REBOA (Resuscitative Endovascular Balloon Occlusion of Aorta):
   • Balloon in Zone III aorta (infrarenal) as bridge to definitive hemorrhage control
   • Buys time, reduces blood loss
7. Definitive fracture fixation:
   • External fixator as definitive or bridge to internal fixation
   • ORIF (open reduction internal fixation) when patient stabilized

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Q9. Abdominal Trauma

a) Internal Organ Injuries in Abdominal Trauma

1. Spleen - Most commonly injured solid organ in blunt trauma; Grade I-V (AAST scale); rupture → hemoperitoneum
2. Liver - Second most common; right lobe more common; may have retrohepatic vena cava injury
3. Kidney - Retroperitoneal; hematuria is hallmark
4. Pancreas - Rare; central blow; transaction at neck (over vertebral column); MRCP/ERCP for ductal injury
5. Adrenal gland - Usually right-sided

b) Management of Grade IV Liver Injury

• ATLS protocol
• Activate massive transfusion protocol (MTP)
• Target MAP >65, UO >0.5 mL/kg/hr

• Only in hemodynamically STABLE patients
• CT with contrast showing Grade IV injury without large volume hemoperitoneum
• Angioembolization if contrast blush
• ICU monitoring, serial hemoglobin, NPO
• Success rate ~70% for Grade IV

1. Pringle maneuver: Manual compression of portal triad (hepatoduodenal ligament) - reduces hepatic inflow; tolerated 30-60 min
2. Perihepatic packing: 3-5 laparotomy pads packed around the liver - primary hemostasis
3. Temporary abdominal closure (Bogota bag/wound vac)
4. Transfer to ICU: correct coagulopathy, hypothermia, acidosis ("lethal triad")

• Debridement of non-viable liver tissue
• Hepatorrhaphy: deep horizontal mattress sutures (chromic/Vicryl)
• Argon beam coagulator / bipolar electrocautery for surface bleeding
• Fibrin sealant/gelatin matrix (Floseal)
• Hepatic artery ligation (right/left branch if necessary)
• Non-anatomical resection (debridement) vs. formal hepatectomy
• For hepatic vein/retrohepatic IVC injury: atriocaval shunt, venous bypass, hepatic vascular isolation

• Bile leak/biloma (drain management, ERCP stenting)
• Hemobilia (angioembolization)
• Hepatic abscess
• Hepatic failure

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Q10. Firearms

a) Common Firearms Used

• Low-velocity (<600 m/s)
• Calibers: .22, .38, 9mm, .45
• Revolvers: cylinder holds 6 rounds; semi-automatic pistols: magazine fed
• Cause: mainly laceration/crushing, minimal cavitation

• High-velocity (600-900 m/s)
• Calibers: 5.56mm (M16/AR-15), 7.62mm (AK-47)
• Cause massive cavitation; significant tissue destruction

• Smooth bore, fires multiple pellets (shot) or single slug
• Short-range: devastating; long-range: multiple small wounds
• Spread pattern helps determine range

• Automatic fire
• SMGs: pistol caliber (9mm)
• Machine guns: rifle caliber, sustained fire

b) Mechanism of Firearm Injury (see Q3 above for detail)

c) Recent Trends in Managing Firearm Injury to Abdomen

1. Damage Control Resuscitation (DCR):
   • Permissive hypotension (SBP 80-90 until hemorrhage control)
   • TXA (tranexamic acid) within 1-3 hours
   • MTP: 1:1:1 (pRBC:FFP:platelets) from the start
   • Avoid crystalloid overload ("too much saline kills")
2. Damage Control Surgery (DCS):
   • Abbreviated laparotomy: stop bleeding + stop contamination only
   • No anastomosis acutely (staple bowel ends)
   • Temporary abdominal closure (VAC/Bogota bag)
   • Resuscitate in ICU, return in 24-48 hrs for definitive repair
3. Non-operative management (NOM):
   • Selected stab wounds: local wound exploration; if not penetrating peritoneum = NOM
   • Low-velocity gunshot wounds to right upper quadrant: selective NOM in stable patients
4. Angioembolization: For solid organ injury with arterial blush on CT
5. REBOA (Resuscitative Endovascular Balloon Occlusion of Aorta):
   • Zone III for pelvic hemorrhage; Zone I for thoracoabdominal
6. Negative pressure wound therapy (NPWT/VAC):
   • Open abdomen management after DCL
   • Reduces ileus, prevents intestinal fistula
7. FAST and CT trauma protocols:
   • MDCT with IV contrast is standard in stable patients
   • Whole-body CT ("trauma pan-scan") reduces missed injuries
8. Hybrid operating rooms:
   • Simultaneous angiography + surgery capability

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Q11. Pancreatic Injury in Blunt Abdominal Trauma

• Often delayed (can be occult initially)
• Epigastric pain radiating to back
• Nausea/vomiting
• Peritonism (delayed, as pancreatic juice causes chemical peritonitis)
• Signs of retroperitoneal hematoma

1. Serum amylase/lipase: Elevated (but not specific; may be normal early)
2. CT abdomen with contrast: Identifies pancreatic laceration, ductal injury, peripancreatic fluid, associated injuries
3. MRCP (MR cholangiopancreatography): Best non-invasive test for ductal integrity
4. ERCP: Gold standard for ductal assessment; therapeutic (stenting)
5. Intraoperative pancreatography: If found at laparotomy

• Grade I-II: Non-operative; drainage if peripancreatic collection; NPO, TPN
• Grade III (distal ductal injury): Distal pancreatectomy ± splenectomy (or spleen-preserving)
• Grade IV (proximal ductal injury): Complex; options:
  • Damage control: wide drainage, no resection acutely
  • Pancreaticoduodenectomy (Whipple) - high morbidity acutely; staged approach preferred
  • ERCP stenting across injury
• Grade V: Pancreaticoduodenectomy eventually; acute = damage control + drainage

• Pseudocyst (most common delayed complication)
• Pancreatic fistula
• Pancreatitis
• Abscess

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Q12. Closed Renal Trauma

• Motor vehicle accidents, falls, sports injuries, direct blow to flank
• Predisposing: hydronephrosis, renal cyst, horseshoe kidney (more vulnerable)

• Flank pain, loin tenderness
• Hematuria (macroscopic or microscopic) - hallmark but severity does NOT correlate with injury grade
• Flank bruising/ecchymosis (Grey-Turner sign)
• Palpable flank mass (retroperitoneal hematoma)
• Shock (Grade IV-V injury)

1. Urinalysis: Hematuria confirms urinary tract injury
2. Serum Cr/BUN: Baseline renal function
3. FAST: Retroperitoneal fluid
4. CT with contrast (arterial + delayed phases):
   • Gold standard; AAST grading I-V
   • Delayed phase (10-15 min): assesses collecting system/urinary extravasation
   • Look for: cortical lacerations, segmental infarcts, contrast extravasation, perinephric hematoma, vascular pedicle injury
5. IVU (intravenous urogram): Limited role now; one-shot IVU intraoperatively if no preop CT
6. Renal angiography: For suspected vascular injury, also therapeutic (embolization)

• Grade I-III: Conservative (bed rest, IV fluids, analgesia, monitoring); urology follow-up; Grade III may need embolization if active bleed
• Grade IV: Conservative if stable; angioembolization for arterial blush; stent/PCN for urinary extravasation
• Grade V: Usually operative; nephrectomy vs. reconstruction (explore if unstable; renorrhaphy, partial nephrectomy if possible)
• Absolute indication for exploration: Expanding/pulsatile retroperitoneal hematoma at laparotomy, hemodynamic instability

• Delayed hemorrhage (2nd-3rd week)
• Urinoma/urinary fistula
• Perirenal abscess
• Hypertension (Page kidney from compression; Goldblatt from renal artery stenosis)
• Renal atrophy
• Pseudoaneurysm/AV fistula
• Post-traumatic hydronephrosis

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Q13. GI Bleeding

a) Causes of Lower GI Bleeding in Adults

1. Hemorrhoids (most common)
2. Colorectal carcinoma
3. Diverticular disease (most common cause of massive LGIB)
4. Angiodysplasia (arteriovenous malformation) - elderly
5. Inflammatory bowel disease (UC, Crohn's)
6. Infective colitis
7. Ischemic colitis
8. Anal fissure

b) Management of Actively Bleeding Hemorrhoids

• Bed rest, ice packs to perineum
• High-fiber diet, stool softeners (lactulose, ispaghula)
• Warm sitz baths
• Topical preparations (lidocaine, hydrocortisone) for symptoms

1. Rubber band ligation (RBL): Band applied at base of hemorrhoid (2-3 cm above dentate line); causes ischemic necrosis; most effective for Grades I-III; 80% success rate; repeat in 4-6 weeks
2. Sclerotherapy: 5% phenol in almond oil injected; Grades I-II
3. Infrared photocoagulation/bipolar coagulation: Grades I-III

1. Hemorrhoidectomy (Milligan-Morgan / Ferguson): Excision of hemorrhoid vascular pedicle; most definitive; complications: pain, retention, stenosis
2. Stapled hemorrhoidopexy (PPH - Procedure for Prolapse and Hemorrhoids): Circular stapler; faster recovery, less pain; risk of rare serious complications (pelvic sepsis)
3. HALO/THD (Hemorrhoidal Artery Ligation): Doppler-guided ligation of hemorrhoidal arteries; less invasive

• Excision under local anesthesia within 72 hours

c) Definition of Upper GI Bleed

d) Causes of Upper GI Bleed

1. Duodenal ulcer (most common)
2. Gastric ulcer
3. Gastric erosions/gastritis

e) Management of Extra-Hepatic Portal Vein Obstruction (EHPVO)

1. Resuscitation (blood transfusion, FFP)
2. Vasoactive drugs: terlipressin/octreotide (reduce portal pressure)
3. Endoscopic variceal band ligation (EVL) or sclerotherapy - first-line
4. Sengstaken-Blakemore tube: balloon tamponade as bridge
5. TIPS (transjugular intrahepatic portosystemic shunt): limited role in EHPVO (no intrahepatic pathology; portal vein often thrombosed)

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Q14. Posterior Urethral Valves (PUV)

• Antenatal: Oligohydramnios, bilateral hydronephrosis, keyhole sign (dilated bladder + posterior urethra) on US
• Neonate: Poor urinary stream, dribbling, palpable bladder/kidneys, respiratory distress (pulmonary hypoplasia), urosepsis
• Child: Recurrent UTI, failure to thrive, daytime wetting
• Adolescent/Adult: Voiding dysfunction, renal insufficiency

1. Renal/bladder ultrasound: bilateral hydronephrosis, thick-walled bladder, dilated posterior urethra
2. Micturating cystourethrogram (MCUG): keyhole appearance at posterior urethra, vesicoureteral reflux
3. Serum creatinine: assess renal function
4. MAG3 renogram: differential renal function

1. Resuscitation: Catheterization (8Fr feeding tube) - emergency drainage
2. Correction of electrolytes, renal failure
3. Endoscopic valve ablation: Transurethral valve ablation (TUVA) using cold knife/hook - definitive treatment; performed when child is stable and urethra accommodates resectoscope
4. Cutaneous vesicostomy: Temporary diversion if urethra too small for resectoscope or in sick neonate
5. High urinary diversion: Loop ureterostomy for poor upper tract function
6. Post-ablation follow-up: Serial US, MCUG, renal function, urodynamics
7. Long-term: 50% progress to chronic renal failure; renal transplantation may be needed

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Q15. Urodynamic Evaluation of the Urinary Tract

1. Uroflowmetry (non-invasive):
   • Measures urine flow rate vs. time
   • Parameters: maximum flow rate (Qmax - normal male ≥15 mL/s), voided volume, voiding time, average flow rate, flow curve shape (bell-shaped normal)
   • Post-void residual (PVR) by bladder scan: <50 mL normal
2. Cystometry (filling cystometry):
   • Catheter fills bladder with saline/CO2; measures intravesical pressure (Pves), abdominal pressure (Pabd), detrusor pressure (Pdet = Pves - Pabd)
   • Detects: detrusor overactivity (DO), reduced compliance, bladder capacity, sensation (first desire, strong desire, maximum capacity)
3. Pressure-flow study (voiding cystometry):
   • Simultaneous detrusor pressure + flow during voiding
   • Bladder outlet obstruction index (BOOI = Pdet at Qmax - 2×Qmax)
   • Distinguishes obstruction from impaired contractility
4. Electromyography (EMG):
   • Perineal/sphincter EMG
   • Detects detrusor-sphincter dyssynergia (DSD)
5. Video-urodynamics:
   • Combines fluoroscopy with cystometry
   • Visualizes bladder neck, urethra during filling/voiding
   • Gold standard for neuropathic bladder
6. Ambulatory urodynamics:
   • Natural filling (no catheter pump), more physiological
   • Used when standard testing is inconclusive
7. Urethral pressure profilometry:
   • Measures urethral closure pressure along urethra
   • Assesses urethral incompetence in stress incontinence

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Q16. Urological Topics

a) Investigation and Management of Urethral Stricture

• Infective: gonorrheal (anterior urethra), tuberculosis
• Traumatic: straddle injury (bulbar urethra), catheterization trauma, pelvic fracture (posterior)
• Iatrogenic: TURP, endoscopy
• Inflammatory: lichen sclerosus (BXO - penile/meatal)
• Idiopathic

1. Uroflowmetry: Reduced Qmax, plateau curve
2. Urethrogram (ascending/retrograde): Location, length, severity
3. Micturating cystourethrogram (MCU): For posterior strictures
4. Urethroscopy: Direct visualization, assess spongiofibrosis
5. Ultrasound urethrogram: Assesses depth of fibrosis (better than X-ray)
6. Urodynamics: Pressure-flow study if needed

1. Urethral dilatation:
   • Using filiforms and followers or balloon dilation
   • Temporary measure; high recurrence
   • For short, soft strictures
2. Direct Visual Internal Urethrotomy (DVIU / Sachse):
   • Cold knife incision at 12 o'clock position
   • Best for: bulbar, short (<1.5 cm), primary (first-time) strictures
   • Recurrence high for long/penile strictures
3. Urethroplasty (gold standard for recurrent/complex strictures):
   • Anastomotic urethroplasty (EPA): Excision + primary end-to-end anastomosis; for short bulbar strictures <2 cm; excellent results (>90%)
   • Substitution urethroplasty:
     • Buccal mucosal graft (BMG) - gold standard graft material (hairless, moist, easy harvest)
     • Fasciocutaneous flap (penile skin, scrotal flap - Quartey, McAninch)
     • Dorsal onlay / ventral onlay / augmented anastomotic
   • For pelvic fracture urethral injuries: perineal anastomotic urethroplasty
4. Permanent urethral stents: Limited role (UroLume stent - for poor surgical candidates)
5. Suprapubic catheter: If cannot pass catheter; bridge to definitive treatment

b) Clinical Features and Management of Fournier's Gangrene

• Severe perineal/scrotal pain, swelling, erythema (early)
• Crepitus (gas in tissues - pathognomonic)
• Woody induration, skin color changes (red → purple → black)
• Foul-smelling discharge
• Systemic: fever, tachycardia, hypotension, septic shock
• Testes usually SPARED (separate blood supply from testicular artery)

1. Bloods: FBC (leukocytosis), U&E (renal failure), glucose (hyperglycemia), ABG (acidosis), coagulation (DIC), CK
2. X-ray perineum: subcutaneous gas
3. CT perineum: extent of gas, fascial plane involvement, source identification (best for surgical planning)
4. Wound swab/blood cultures

1. Resuscitation: IV fluids, broad-spectrum antibiotics IV immediately:
   • Piperacillin-tazobactam OR imipenem
   • • Metronidazole (anti-anaerobic)
   • • Vancomycin/teicoplanin (MRSA cover)
2. Emergency radical surgical debridement (WITHIN HOURS):
   • Wide excision of all necrotic tissue to bleeding, viable margins
   • Leave scrotum open, pack with saline-soaked gauze or honey
   • Testes exposed but preserved (their blood supply is separate)
   • Diverting colostomy if anorectal involvement
   • Suprapubic catheter if urethral involvement
3. Repeat debridement: Every 24-48 hrs until clean wound
4. Wound care:
   • NPWT (VAC therapy) after clean wound
   • Dressing changes with honey/povidone iodine
5. Hyperbaric oxygen (HBO): Adjunct; inhibits anaerobes, enhances macrophage killing, improves wound healing; controversial
6. Reconstruction:
   • Split-thickness skin graft (STSG) once clean granulating wound
   • Scrotal reconstruction: local flaps (medial thigh flap)

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Q17. Radiolucent Urinary Tract Stones

1. Uric acid stones (most common radiolucent stone, 5-10%):
   • Pure uric acid is radiolucent; mixed uric acid may be faintly opaque
   • Causes: hyperuricemia (gout, myeloproliferative disorders), low urine volume, persistently acidic urine (pH <5.5), ileostomy
   • CT shows: dense stones (HU ~200-450); US: echogenic with acoustic shadow
2. Xanthine stones: Very rare; xanthinuria (deficiency of xanthine oxidase); completely radiolucent
3. Indinavir stones: Drug-induced (HIV protease inhibitor); radiolucent on CT too
4. Matrix stones: Composed of mucoprotein matrix; radiolucent; associated with Proteus infection
5. Ammonium urate stones: Occasionally radiolucent

• CT KUB (non-contrast) is GOLD STANDARD - identifies all stones regardless of composition
• Urinalysis: hematuria, pH (acid urine → uric acid stones)
• 24-hr urine: uric acid, oxalate, citrate
• Serum uric acid
• Stone analysis (after passage/retrieval)

1. Urinary alkalinization: Potassium citrate/sodium bicarbonate to raise urine pH to 6.5-7.0 → uric acid dissolves (chemolysis)
2. Increased fluid intake: >2.5 L/day
3. Allopurinol: If hyperuricemia (reduces uric acid production)
4. Low-purine diet
5. ESWL: If chemolysis fails; uric acid stones respond well
6. Ureteroscopy/PCNL: For large or refractory stones

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Q18. Obstructive Uropathy in a 65-Year-Old Man [6]

• Ureteric stone
• Blood clot
• Sloughed papilla (analgesic nephropathy, DM)

• Ureteric stricture
• Ureteral carcinoma
• TCC of bladder (ureteric orifice)
• Neurogenic bladder

• Benign prostatic hyperplasia (BPH) - most common cause in 65-yr-old male
• Prostatic carcinoma
• Colorectal carcinoma
• Retroperitoneal fibrosis
• Retroperitoneal lymphoma/metastasis
• Aneurysm (aortic/iliac)

• Obstructive symptoms: hesitancy, poor stream, straining, incomplete emptying, post-void dribbling
• Irritative symptoms: frequency, urgency, nocturia
• Overflow incontinence
• Acute urinary retention
• Symptoms of renal failure (if bilateral obstruction/chronic): nausea, fatigue, edema

1. History: IPSS score, drug history (anticholinergics, alpha-agonists)
2. Examination: Distended bladder, DRE (prostate size, consistency, nodules)
3. Urine: R/E, culture
4. Bloods: Serum creatinine, eGFR, PSA, FBC
5. Ultrasound KUB: Hydronephrosis, hydroureter, PVR, prostate volume
6. Flexible cystoscopy: Bladder/prostate assessment, TCC
7. Urodynamics (pressure-flow study): Distinguish obstruction from impaired contractility
8. CT urogram: If ureteric obstruction suspected, mass lesion
9. MRI pelvis: For prostate/rectal carcinoma assessment
10. Bone scan: If PSA elevated (carcinoma metastases)

• BPH (most common):
  • Medical: alpha-blockers (tamsulosin, alfuzosin), 5-alpha reductase inhibitors (finasteride, dutasteride)
  • Minimally invasive: UroLift, Rezum water vapor therapy
  • Surgical: TURP (gold standard), HoLEP, open prostatectomy (large glands)
• Prostatic carcinoma: Active surveillance, radical prostatectomy, radiotherapy, ADT, enzalutamide
• Ureteric obstruction: Stenting (DJ stent), nephrostomy, treat underlying cause
• Bilateral obstruction/acute renal failure: Emergency catheterization or nephrostomy, dialysis

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Q19. 25-Year-Old with Progressive Thinning and Dual Stream (Urethral Stricture/Meatal Stenosis) [2+4+4]

• Urethral stricture (anterior urethra - penile/bulbar) - see Q16a for causes
• Meatal stenosis (if split stream is at meatus): BXO (lichen sclerosus)/post-circumcision scarring

• Fibrosis and spongiofibrosis following: trauma (straddle injury, catheterization), infection (gonorrhea - penile urethra), BXO (lichen sclerosus et atrophicus affecting meatus/penile urethra), idiopathic
• Collagen replaces normal spongiosum → loss of elasticity → narrowing

1. History: onset, duration, dysuria, previous STI, catheterization, trauma, circumcision
2. Examination: meatus (stenosis, BXO plaques), palpate urethra for induration
3. Uroflowmetry: Qmax reduced, plateau curve
4. Retrograde urethrogram (RUG): Location, length, caliber of stricture
5. Urethroscopy (flexible cystoscopy): Direct visualization
6. Ultrasound urethrogram (UUSG): Depth of fibrosis (determines reconstruction approach)
7. Urine culture (if UTI)
8. MCUG (if posterior stricture also suspected)

1. Meatotomy: For isolated meatal stenosis (incision under LA, meatoplasty)
2. Dilatation: For soft/short strictures (temporary)
3. DVIU (Direct Visual Internal Urethrotomy): First-line for short (<1.5 cm), non-dense, primary strictures
4. Urethroplasty (definitive):
   • Anastomotic: for short bulbar strictures (excision + primary anastomosis)
   • Buccal mucosal graft (BMG) onlay: for longer strictures >2 cm, penile strictures
   • BXO strictures: BMG preferred (penile skin is diseased in BXO)
5. Regular urethral dilation as palliation in those unfit for surgery

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Q20. 10-Year-Old Boy with Paradoxical Urinary Incontinence + Normal Voiding (Posterior Urethral Valves / Ectopic Ureter) [3+3+4]

• Normally the ureter bud arises from the mesonephric (Wolffian) duct and is absorbed into the trigone - both ureters open above the bladder neck
• If the ureteric bud arises more cranially on the Wolffian duct, the orifice migrates further caudally (below bladder neck/sphincter) - "ectopic ureter"
• In males: ectopic ureter opens into the bladder neck, posterior urethra, seminal vesicle, ejaculatory duct, or vas deferens - ALL are ABOVE the external sphincter → continence maintained (they are continent despite ectopic ureter)

1. Renal/bladder ultrasound: duplex kidney, upper pole hydronephrosis, ectopic ureteric orifice
2. Intravenous urogram (IVU): "Drooping lily" sign (lower moiety displaced downward by upper moiety)
3. Cystoscopy: Identify ectopic orifice
4. MCU: VUR in lower moiety
5. DMSA scan: Differential function of upper/lower poles
6. MRI urography: Best for complex anatomy

• Upper pole nephroureterectomy: If upper pole has <10% function (most common treatment)
• Ureteroureterostomy (upper to lower ureter): If upper pole has salvageable function (>10%)
• Re-implantation (neoureterocystostomy): If long ectopic ureter with good upper pole function
• Endoscopic incision: For ureterocele causing obstruction
• Observation: If asymptomatic with good function

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Q21. 10 mm Stone at Vesico-Ureteric Junction (VUJ) in Solitary Functioning Kidney [2+3+5]

Clinical Presentation [2]

• Ureteric colic: Severe, colicky flank/loin pain radiating to groin/scrotum/labia
• Urgency, frequency (stone at VUJ irritates bladder trigone)
• Hematuria (macro or micro)
• Nausea/vomiting
• Oliguria/anuria - if complete obstruction in a solitary kidney (EMERGENCY)
• Signs of infection: fever, rigors (obstructed infected kidney = urological emergency)
• Tenderness: renal angle/loin, suprapubic

Evaluation [3]

1. Urine: R/E (hematuria, pyuria), culture (infection)
2. Blood: FBC, U&E (CRITICAL - serum creatinine/eGFR - rising in obstruction), electrolytes (hyperkalemia)
3. CT KUB (non-contrast): Gold standard; confirms stone at VUJ, measures HU (density), perinephric fat stranding (obstruction), hydronephrosis
4. Ultrasound: Hydronephrosis, bladder stone if passed; used if CT not available
5. Plain X-ray KUB: Opaque stone? (but VUJ stones often hidden by bony pelvis)
6. IVU: Shows degree of obstruction but uses contrast (nephrotoxic if impaired)

• Rising creatinine, hyperkalemia, acidosis = acute renal failure from obstruction - urgent drainage
• Even partial obstruction is dangerous
• Avoid nephrotoxic contrast if creatinine elevated

Management [5]

1. Ureteric stenting (DJ stent): Cystoscopic retrograde placement; immediate relief; allows definitive treatment later
2. Percutaneous nephrostomy (PCN): If ureteric stenting fails or retrograde access impossible; ultrasound-guided; immediate decompression
3. IV fluids, analgesia (diclofenac IM/IV, morphine), antiemetics
4. IV antibiotics if infected (gentamicin + ampicillin or piperacillin-tazobactam)

• Alpha-blocker (tamsulosin 0.4 mg OD) ± nifedipine
• Increases spontaneous passage rate, reduces colic
• Used as bridge or adjunct; trial for 4-6 weeks if small stone

1. Ureteroscopy (URS) + Laser lithotripsy (Ho:YAG):
   • Treatment of choice for 10mm VUJ stone
   • Semi-rigid or flexible ureteroscope
   • Direct visualization + fragmentation with holmium laser
   • Fragments removed with basket
   • DJ stent placed for 1-4 weeks post-procedure
   • Success rate >95% for VUJ stones
2. ESWL (Extracorporeal Shock Wave Lithotripsy):
   • Non-invasive; can be used for VUJ stones
   • Less effective than URS for distal ureteric stones
   • Requires stone to be visible on fluoroscopy
   • Multiple sessions may be needed

• Ensure drainage before any intervention if renal function impaired
• Avoid prolonged stenting (infection risk, encrustation)
• Monitor renal function closely after treatment
• Long-term follow-up: metabolic evaluation for stone prevention (24-hr urine, serum calcium/uric acid)

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Q22. Nephroblastoma vs Neuroblastoma

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Q23. Diabetic Foot Gangrene

a) Pathophysiology

• Accelerated atherosclerosis of tibial/peroneal vessels (infrapopliteal occlusion)
• Medial calcification (Mönckeberg's) - stiffens vessels without necessarily causing occlusion
• Reduced ABI (<0.9); non-compressible vessels in DM (falsely elevated ABI)
• Macrovascular disease → critical limb ischemia → necrosis

• Sensory neuropathy: loss of protective sensation → unrecognized trauma (shoe pressure, foreign bodies, burns)
• Motor neuropathy: intrinsic muscle wasting → clawing of toes, altered pressure distribution (high metatarsal head pressure) → callus formation
• Autonomic neuropathy: loss of sweating → dry, fissured skin; AV shunting → increased blood flow to superficial layers bypassing nutritive capillaries

• Impaired PMN function (high glucose impairs chemotaxis, phagocytosis, killing)
• Polymicrobial infection (aerobic gram-positive + gram-negative + anaerobes)
• Rapidly spreading cellulitis, myonecrosis, osteomyelitis
• Gas-forming organisms (Clostridia, E. coli) → crepitus

• Wet gangrene (more common in DM): Ischemia + infection → liquefaction necrosis; foul smell, spreading
• Dry gangrene: Pure ischemia → mummification

• Grade 0: No ulcer, at-risk foot
• Grade 1: Superficial ulcer
• Grade 2: Deep ulcer (tendon/joint)
• Grade 3: Deep ulcer with abscess/osteomyelitis
• Grade 4: Partial forefoot gangrene
• Grade 5: Whole foot gangrene

b) Recent Advances in Treatment of Diabetic Foot Ulcers

1. Negative Pressure Wound Therapy (NPWT/VAC):
   • Continuous or intermittent subatmospheric pressure (125 mmHg)
   • Increases granulation tissue, removes exudate, reduces edema, promotes blood flow
   • Standard of care for complex wounds
2. Endovascular revascularization:
   • Percutaneous transluminal angioplasty (PTA) with drug-eluting balloons (DEB)
   • Tibial vessel angioplasty for infrapopliteal disease
   • Below-the-knee interventions specifically designed for DM
3. Biological wound dressings:
   • Acellular dermal matrices (Integra, OASIS)
   • Placental-derived allografts
   • Promote neodermis formation
4. Growth factor therapy:
   • Platelet-derived growth factor (PDGF/Becaplermin/Regranex)
   • Platelet-rich plasma (PRP) injections
   • EGF (epidermal growth factor) topical
5. Stem cell therapy:
   • Autologous bone marrow mononuclear cells (BM-MNC) injection into ischemic tissue
   • Angiogenesis promotion; improving results in trials
6. Hyperbaric Oxygen Therapy (HBOT):
   • 100% O2 at 2-3 atm
   • Promotes angiogenesis, collagen synthesis, kills anaerobes
   • Grade 3-4 DFU evidence supporting use
7. Bioengineered skin substitutes:
   • Apligraf (bilayer: keratinocytes + fibroblasts)
   • Dermagraft (fibroblast-seeded scaffold)
8. Maggot debridement therapy (MDT):
   • Sterile Lucilia sericata larvae
   • Selective enzymatic debridement of necrotic tissue
   • Effective for chronic, sloughy wounds
9. Offloading devices:
   • Total contact casting (TCC) - gold standard for neuropathic plantar ulcers
   • Removable cast walker
10. Multidisciplinary diabetic foot clinic: Diabetologist + vascular surgeon + orthopedic surgeon + podiatrist + wound care nurse

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Q24. Arterio-Venous Fistula (AVF)

Clinical Features

• Present from birth; may enlarge with growth
• Pulsatile swelling, thrill, bruit over the lesion
• Limb hypertrophy/lengthening (due to increased blood flow)
• Local warmth, skin changes (varicosities, telangiectasias, ulceration)

• History of penetrating injury/procedure at site
• Pulsatile swelling at site
• Thrill (palpable vibration) on palpation
• Machinery bruit (continuous, louder in systole) on auscultation
• Branham-Nicholadini sign: Manual compression of AVF → immediate bradycardia and rise in BP (reflex from sudden increase in peripheral resistance)
• Distal ischemia: Cold, pale limb distal to fistula (steal phenomenon)
• Distal venous hypertension: Varicosities, edema, venous ulcers
• High-output cardiac failure: Large, long-standing AVF → tachycardia, cardiomegaly, CCF

Investigative Workup and Interpretation

1. Duplex Doppler ultrasound (first-line):
   • Identifies fistula tract
   • Shows arterial-pattern flow in vein (pulsatile venous flow)
   • Measures flow velocity and volume
   • Determines anatomy for planning
2. CT Angiography:
   • Defines anatomy, feeding vessels, draining veins
   • Extent of fistula, involvement of adjacent structures
3. MR Angiography:
   • Excellent soft tissue definition
   • Particularly for congenital AVMs
   • No ionizing radiation
4. Conventional Angiography (DSA - Digital Subtraction Angiography):
   • Gold standard for vascular anatomy
   • Shows early venous filling (arterial contrast appears in veins within seconds)
   • Needed for pre-embolization mapping
   • Therapeutic (embolization)
5. Echocardiography:
   • Assess cardiac output, LV function in large/long-standing fistulas
   • LV dilatation, high output state
6. Interpretation findings:
   • Increased arterial flow to fistula, turbulence at communication
   • Arterialized venous flow (high-velocity, pulsatile)
   • Varices, enlarged feeding artery
   • Distal arterial flow may be reduced (steal)

Principles of Management of AVF

1. Endovascular therapy (preferred first-line for most):
   • Coil embolization: For small fistulas, muscular AVMs
   • Covered stent graft: For acquired traumatic AVF in large vessels (femoral, popliteal) - occludes fistula while maintaining vessel continuity; excellent results
   • Glue/Onyx embolization: For complex congenital AVMs
2. Open surgery:
   • Quadruple ligation and excision: Proximal artery, distal artery, proximal vein, distal vein - then excise fistula
   • For traumatic AVF: repair the arterial defect (direct repair, patch, interposition graft)
   • For congenital AVM: staged excision after embolization (combined approach)
3. Compression therapy:
   • Minor iatrogenic AVF (e.g., post-cardiac catheterization) may close with prolonged compression
4. Staged embolization + surgery:
   • Pre-operative embolization reduces intraoperative blood loss
   • Then surgical excision
5. Timing:
   • Urgent: cardiac failure, distal ischemia, rupture
   • Elective: stable fistulas

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Q25. Therapeutic Embolization

• GI bleeding (varices, angiodysplasia, diverticular bleed, post-polypectomy)
• Hemoptysis (bronchial artery embolization)
• Post-traumatic hemorrhage (liver, spleen, kidney, pelvis)
• Post-partum hemorrhage (uterine artery embolization - UAR)
• Epistaxis (ECA embolization)

• Hepatocellular carcinoma (TACE - transarterial chemoembolization)
• Renal cell carcinoma (pre-operative or palliative)
• Uterine fibroids (UFE - uterine fibroid embolization)
• Meningioma (pre-operative)
• Bone metastases

• Cerebral AVM, spinal AVM, peripheral AVMs
• Pulmonary AVMs (hereditary hemorrhagic telangiectasia)

• Splenic vein embolization for gastric varices
• TIPS for refractory variceal bleeding
• Varicocele embolization

• Temporary: Gelfoam (resorbs in weeks)
• Permanent particles: PVA particles, embospheres, beads
• Coils: Metallic coils (mechanical occlusion)
• Liquids: Cyanoacrylate (glue), Onyx (ethylene vinyl alcohol), ethanol
• Balloons: Detachable balloons for large vessels

1. Femoral (or radial) artery access under LA
2. Diagnostic angiogram to identify bleeding vessel/lesion
3. Super-selective catheterization (coaxial microcatheter)
4. Deploy embolic agent under fluoroscopy
5. Post-embolization angiogram to confirm occlusion

• Post-embolization syndrome: fever, pain, leukocytosis (self-limiting)
• Non-target embolization (ischemia of adjacent organs)
• Access site complications (hematoma, pseudoaneurysm)
• Contrast nephropathy
• Infection/abscess

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Q26. Dry Gangrene

• Severe peripheral arterial disease (atherosclerosis)
• Buerger's disease (thromboangiitis obliterans)
• Raynaud's phenomenon (severe/progressive)
• Ergotism
• Frostbite
• Embolism (acute arterial occlusion)
• Diabetes mellitus (ischemic form)

• Arterial occlusion → ischemia → cells die → autolytic enzymes activity low (dry environment, no water)
• Coagulative necrosis (proteins denatured, cells ghost-like)
• Loss of water → mummification (shrinks, desiccates)
• Bacteria cannot grow well in dry, avascular tissue
• No infection → no toxins → no systemic toxicity usually
• A LINE OF DEMARCATION forms between viable and non-viable tissue

• Part is cold, black/dark brown
• Dry, shriveled, leathery appearance
• No smell (no infection)
• Clear line of demarcation
• May be painful (ischemia) initially, then anesthetic (nerve death)
• No systemic toxicity unless infection supervenes

1. Treat underlying cause: Antiplatelet agents, statins, glycemic control
2. Revascularization: If viable distal vessels exist:
   • Angioplasty/stenting
   • Bypass surgery (femoropopliteal, femorodistal)
3. Allow demarcation to establish (do not rush to amputate)
4. Conservative care of the gangrenous part: Keep dry, povidone-iodine dressings, prevent trauma/pressure
5. Amputation once line of demarcation clear:
   • Through the level of demarcation or at the next joint proximal
   • Toe/ray amputation, below-knee, above-knee depending on level
6. Anticoagulation: If embolic cause (warfarin, heparin)

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Q27. Arterial vs Venous Ulcer

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Q28. Types of Amputations for the Lower Limb

1. Toe amputation (digital): For digital gangrene; trans-phalangeal, Ray (digit + metatarsal head)
2. Transmetatarsal amputation (TMA): Through mid-shaft metatarsals; good for forefoot gangrene
3. Lisfranc amputation: Through tarsometatarsal joints
4. Chopart amputation: Through midtarsal joint (calcaneocuboid + talonavicular); risk of equinus deformity
5. Syme's amputation: Through ankle joint (tibiotalocalcaneal); leaves good heel pad; excellent prosthetic fitting
6. Below-knee (BK) / Transtibial amputation: 10-15 cm below tibial tuberosity; best functional outcome with prosthesis; posterior flap (skew flap)
7. Knee disarticulation: Through knee joint; long lever arm, no bone transection
8. Above-knee (AK) / Transfemoral amputation: Mid-thigh; equal anterior and posterior flaps; for extensive disease or failed BK
9. Hindquarter amputation (hemipelvectomy): For tumors; removes entire lower limb + hemipelvis
10. Hip disarticulation: Entire lower limb at hip joint; for tumors/trauma

• Adequate soft tissue coverage (flaps should be tension-free)
• Beveled bone end (smooth)
• Good hemostasis, ligated vessels
• Nerves cut short (prevent neuroma)
• Muscles balanced (myodesis/myoplasty)
• No tension on suture line
• Drain placed

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Q29. Vascular Injuries of Extremities

• Absent/diminished pulse distal to injury
• Active pulsatile hemorrhage
• Expanding/pulsatile hematoma
• Distal ischemia (6Ps: Pain, Pallor, Pulselessness, Paresthesia, Paralysis, Poikilothermia)
• Audible bruit / palpable thrill

• Proximity of injury to major vessels
• Stable hematoma
• Reduced ABI (<0.9)
• Neurological deficit (adjacent nerve injury)
• Hypotension

1. ABI (ankle-brachial index): <0.9 suggests vascular injury
2. CT Angiography: Investigation of choice in stable patients; identifies injury, extent, guides repair
3. Duplex ultrasound: Bedside; noninvasive
4. Conventional angiography: Gold standard; also therapeutic (embolization for pseudoaneurysm, stenting)
5. Surgical exploration: If hard signs present - no time for imaging

1. Control hemorrhage: Direct pressure (tourniquet for limbs), no blind clamping
2. ATLS resuscitation: MTP if massive hemorrhage
3. Definitive vascular repair:
   • Lateral suturorrhaphy: simple laceration <50% circumference
   • Resection + end-to-end anastomosis: short segment injury
   • Interposition graft: reversed saphenous vein (GSV) preferred; synthetic PTFE/Dacron for larger vessels
   • Patch angioplasty: wider repair without narrowing
   • Ligation: for non-critical vessels (EJV, inferior mesenteric, etc.)
   • Endovascular: covered stent-graft (iliac, femoral, subclavian injuries in stable patients)
4. Fasciotomy: Prophylactic if >4-6 hours ischemia time; definitive after reperfusion edema
5. Orthopedic injuries: Vascular repair BEFORE fracture fixation if limb ischemic; external fixation used
6. Anticoagulation: Systemic heparin during repair; postoperatively in some cases

• Hourly pulse checks/Doppler assessment
• Limb elevation
• Serial ABIs
• Re-exploration if graft thrombosis/limb deterioration
• Physiotherapy

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Q30. Congenital Vascular Lesions of Skin

• Infantile Hemangioma (strawberry hemangioma): Most common vascular tumor; not present at birth; appears at 1-4 weeks; rapid growth in first year; then spontaneous involution (50% by age 5, 70% by 7, 90% by 9); superficial (bright red), deep (bluish), or compound; Rx: observation (most), propranolol (first-line if treatment needed), timolol gel, corticosteroids, laser, surgery (if vision/airway threat, ulceration, failed medical Rx)
• Rapidly Involuting Congenital Hemangioma (RICH): Present at birth, fully formed; involutes completely within 1 year
• Non-Involuting Congenital Hemangioma (NICH): Present at birth; does NOT involute
• Kaposiform Hemangioendothelioma (KHE): Associated with Kasabach-Merritt phenomenon (thrombocytopenia + coagulopathy); requires treatment (vincristine, sirolimus)

• Capillary malformations:
  • Port-wine stain (nevus flammeus): unilateral; face (V1/V2); Sturge-Weber syndrome (ipsilateral leptomeningeal angioma + glaucoma + seizures); Rx: pulsed dye laser (585/595 nm) - treatment of choice
  • Salmon patch / stork bite (nevus simplex): midline; fades spontaneously
• Venous malformations (VM): Soft, compressible, bluish; enlarge with Valsalva; thrombosis/phleboliths; sclerotherapy (Sotradecol, Bleomycin, Polidocanol) ± surgery
• Lymphatic malformations:
  • Macrocystic (cystic hygroma): large cysts; neck/axilla; sclerotherapy (doxycycline, bleomycin/OK-432) ± surgery
  • Microcystic: vesicles on skin surface; harder to treat
  • Sirolimus (mTOR inhibitor): emerging treatment for complex/unresectable lymphatic malformations
• Arteriovenous malformations (AVM): High-flow; warm, pulsatile; bruit; aggressive growth after puberty/trauma; Schobinger staging; Rx: combined embolization + resection; high recurrence
• Combined malformations:
  • Klippel-Trenaunay syndrome: capillary + venous + lymphatic + limb hypertrophy (no AV component)
  • Parkes-Weber syndrome: capillary + AVM + limb hypertrophy

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Q31. Arterial Repairs - Basic Principles and Post-operative Management

a) Basic Principles of Major Arterial Repairs

1. Proximal and distal control first - clamp/tourniquet before entering hematoma (prevent exsanguination)
2. Adequate exposure - generous incisions, mobilize vessel above and below injury
3. Debridement - excise damaged/contaminated vessel ends back to healthy tissue
4. Systemic heparinization - 100 units/kg IV heparin before clamping (prevents distal thrombus); only if no contraindication (major hemorrhage)
5. Thrombectomy - Fogarty balloon catheter proximally and distally to remove thrombus
6. Flushing - heparinized saline (100 U/mL) into all stumps before repair
7. Tension-free anastomosis - mobilize vessel ends; never anastomose under tension (causes thrombosis, anastomotic disruption)
8. Choice of repair technique:
   • Simple laceration (<50% circumference): lateral suturorrhaphy
   • Segmental loss <2 cm: excision + end-to-end anastomosis
   • Segmental loss >2 cm or tension: interposition graft
9. Graft material:
   • Autologous reversed saphenous vein (GSV) - BEST for vessels <6 mm; infection-resistant; long-term patency
   • PTFE or Dacron: for larger vessels (aorta, iliac), when vein unavailable
   • Never use prosthetic in contaminated fields
10. Suture technique:
    • Monofilament non-absorbable (polypropylene - Prolene): 5-0 to 7-0 (finer for smaller vessels)
    • Interrupted or continuous; interrupted preferred at anastomosis (allows growth)
11. Assess repair: Doppler confirmation of flow distally; check for leaks
12. Fasciotomy: Prophylactic if prolonged ischemia >4-6 hours or after reperfusion
13. Soft tissue coverage: Never leave graft exposed; cover with viable tissue (muscle flap if needed)

b) Post-operative Management

1. Hourly pulse checks: Doppler assessment of distal pulse quality
2. Duplex surveillance: At 24 hrs, 6 weeks, then annually
3. ABI monitoring: Serial measurements
4. Anticoagulation:
   • IV heparin infusion for 24-48 hrs post-repair (aPTT 50-70 sec)
   • Convert to oral anticoagulation (warfarin/NOACs) for prosthetic grafts or thrombophilia
   • Antiplatelet: aspirin 75-100 mg OD for autologous vein grafts
5. Limb monitoring:
   • Warmth, color, sensation, movement hourly
   • Watch for reperfusion injury: compartment syndrome (fasciotomy if needed)
   • Wound inspection for hematoma
6. Fluid management: Maintain adequate hydration (myoglobinuria from reperfusion → force diuresis with IV fluids ± mannitol)
7. Pain management: Adequate analgesia
8. Physiotherapy: Early mobilization when stable
9. Complications to watch: Graft thrombosis, stenosis, infection, pseudo-aneurysm, AV fistula formation, limb ischemia/reperfusion injury

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Q32. Ideal Amputation Stump + Limb Prosthesis

a) Define Ideal Amputation Stump

1. Adequate length: Sufficient lever arm for prosthetic fitting; not too long (poor vascularity) not too short (poor control)
   • Below-knee: 10-15 cm below tibial tuberosity
   • Above-knee: 15-20 cm below lesser trochanter
2. Well-healed wound: Primary healing without breakdown, infection, or sinus
3. Conical shape: Gently tapering; cylindrical stumps fit prostheses poorly
4. Adequate soft tissue padding: Muscle cover over bone end; no bony prominences
5. Mobile flaps: Skin not adherent to bone (no tethered scar)
6. Painless: No neuroma (nerve cut cleanly and sharply, allowed to retract), no phantom pain ideally
7. Good skin: Sensate, pliable, no ulcers, no dermatitis
8. Stable joints proximal: Full ROM at proximal joint
9. No joint flexion contracture
10. Adequate muscle balance: Myodesis (muscle attached to bone) to prevent retraction and contracture

b) Recent Developments and Applications in Limb Prosthesis

1. Microprocessor-controlled prosthetic knees (MPK):
   • e.g., Ottobock C-Leg, Össur Rheo Knee
   • Hydraulic/pneumatic resistance adjusted by microprocessor in real-time
   • Adapts to varying walking speeds, terrain, stairs
2. Energy-storing and returning (ESAR) feet:
   • Carbon fiber foot (e.g., Flex-Foot Cheetah, Seattle Foot)
   • Stores energy during mid-stance, returns during push-off
   • Improves gait efficiency, enables running
3. Osseointegration (OPRA - Osseointegrated Prostheses for the Rehabilitation of Amputees):
   • Titanium implant directly into residual bone
   • Prosthesis attached transcutaneously
   • Eliminates socket problems (skin breakdown, poor fit), improves proprioception
   • Risk: percutaneous implant infection
4. Myoelectric prostheses (upper limb, also lower):
   • EMG signals from residual muscles control prosthetic joints
   • Targeted Muscle Reinnervation (TMR): residual nerves reinnervated into nearby muscles → improved myoelectric control
5. Bionic prosthetics with sensory feedback:
   • Electrodes implanted in peripheral nerves provide sensory feedback to the user
   • Allows pressure/texture/temperature sensation
6. 3D-printed prosthetics:
   • Custom, lightweight, affordable
   • Rapid fabrication; particularly valuable in low-resource settings and children (frequent replacement with growth)
7. Brain-computer interface (BCI):
   • Cortical recording + decoding of motor intent
   • Direct cortical control of prosthetic limb
   • Experimental but promising
8. Activity-specific prostheses:
   • Running blades, swimming prostheses, cycling attachments
   • Specialized sockets (waterproof, sports-specific)
9. Smart socket technology:
   • Sensors within socket monitor stump volume/shape changes
   • Pneumatically adjustable sockets maintain fit throughout the day

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