AIIMS PG (DM/MCh) Entrance General Surgery and Surgical Super-Specialties Syllabus

In coronary artery bypass grafting, which conduit has the best long-term patency and why?

The left internal mammary (thoracic) artery grafted to the LAD has the best long-term patency (>90% at 10 years) due to its arterial wall structure and resistance to atherosclerosis.

What is the difference between mechanical and bioprosthetic heart valves regarding anticoagulation and durability?

Mechanical valves are highly durable but require lifelong warfarin anticoagulation (thrombogenic). Bioprosthetic valves need no long-term anticoagulation but are less durable (structural degeneration in 10–15 years), favored in elderly patients or those who cannot take anticoagulants.

State the indications for surgery in chronic severe aortic stenosis.

Symptomatic severe AS (angina, syncope, dyspnea/heart failure), asymptomatic severe AS with LVEF <50%, or those undergoing other cardiac surgery. Valve area <1.0 cm² and mean gradient >40 mmHg indicate severe AS.

Describe the pathophysiology and components of Tetralogy of Fallot.

Four features from anterior-cephalad deviation of the infundibular septum: (1) ventricular septal defect, (2) overriding aorta, (3) right ventricular outflow tract obstruction (pulmonary stenosis), and (4) right ventricular hypertrophy. It causes right-to-left shunt (cyanosis).

What is the Blalock-Taussig shunt and its purpose?

A palliative systemic-to-pulmonary artery shunt (subclavian/innominate artery to pulmonary artery, classically; modified version uses a Gore-Tex graft) to increase pulmonary blood flow in cyanotic congenital heart disease such as Tetralogy of Fallot.

Differentiate cyanotic from acyanotic congenital heart disease with examples.

Acyanotic (left-to-right shunt): VSD, ASD, PDA. Cyanotic (right-to-left shunt, the '5 Ts'): Tetralogy of Fallot, Transposition of great arteries, Truncus arteriosus, Tricuspid atresia, Total anomalous pulmonary venous connection.

What is the most common type of esophageal atresia and its association?

Esophageal atresia with distal tracheo-esophageal fistula (Gross type C, ~85%). It is part of the VACTERL association (Vertebral, Anal, Cardiac, TE fistula, Renal, Limb anomalies).

In thoracic surgery, what is the management of a tension pneumothorax?

Immediate needle decompression (large-bore cannula in the 2nd intercostal space mid-clavicular line, or 5th ICS anterior axillary line per newer ATLS), followed by definitive intercostal chest tube (tube thoracostomy) insertion.

What is the most common type of esophageal carcinoma worldwide versus in the lower third, and key risk factors?

Squamous cell carcinoma is most common overall (smoking, alcohol, hot beverages); adenocarcinoma predominates in the lower third and is linked to Barrett's esophagus from chronic GERD.

What is a chylothorax and its characteristic pleural fluid finding?

Accumulation of lymphatic (chyle) fluid in the pleural space, usually from thoracic duct injury (e.g., after esophagectomy). Fluid is milky, with triglycerides >110 mg/dL and presence of chylomicrons.

What is the most common site of an abdominal aortic aneurysm and the threshold diameter for elective repair?

Infrarenal aorta is the most common site. Elective repair is indicated at a diameter ≥5.5 cm (men), ≥5.0 cm in women, rapid expansion (>0.5 cm/6 months), or if symptomatic.

Describe the six P's of acute limb ischemia.

Pain, Pallor, Pulselessness, Paresthesia, Paralysis, and Poikilothermia (Perishingly cold). Paralysis and paresthesia indicate advanced ischemia requiring emergent revascularization.

What is the Fontaine classification of chronic lower limb ischemia?

Stage I: asymptomatic. Stage II: intermittent claudication (IIa >200 m, IIb <200 m). Stage III: rest pain. Stage IV: ulceration or gangrene (tissue loss).

What is the gold-standard diagnostic and the immediate treatment for an acutely thrombosed limb (embolic)?

CT/digital subtraction angiography confirms the level. Immediate management: systemic heparinization, then surgical embolectomy (Fogarty balloon catheter) or catheter-directed thrombolysis; fasciotomy if reperfusion (compartment) syndrome is anticipated.

What is the most common primary malignant brain tumor in adults and its key molecular markers?

Glioblastoma (IDH-wildtype, WHO grade 4 astrocytoma). MGMT promoter methylation predicts response to temozolomide; IDH mutation status now defines the diagnosis and carries better prognosis when present.

What is the most common posterior fossa tumor in children and a common adult cerebellopontine angle tumor?

In children: medulloblastoma (or pilocytic astrocytoma). In adults at the cerebellopontine angle: vestibular schwannoma (acoustic neuroma).

Describe the Hunt and Hess grading of subarachnoid hemorrhage.

Grade I: asymptomatic/mild headache. II: moderate-severe headache, nuchal rigidity, cranial nerve palsy. III: drowsiness/confusion, mild focal deficit. IV: stupor, hemiparesis. V: deep coma, decerebrate posturing. Higher grade = worse prognosis.

What is the most common cause of spontaneous subarachnoid hemorrhage and its most common aneurysm site?

Rupture of a saccular (berry) aneurysm. The most common site is the anterior communicating artery, followed by posterior communicating and middle cerebral artery bifurcation.

What is cerebral vasospasm after SAH, when does it peak, and how is it managed?

Delayed arterial narrowing causing delayed ischemic deficit, peaking on days 4–14 after SAH. Managed with oral nimodipine (prophylactic), euvolemia, and induced hypertension; refractory cases may need endovascular angioplasty.

What is the most common spinal level for disc herniation and the corresponding nerve root affected?

L4–L5 and L5–S1 are most common. A paracentral L4–L5 disc typically compresses the L5 root (foot dorsiflexion weakness); L5–S1 compresses S1 (ankle plantar flexion, absent ankle jerk).

Describe the components of the Glasgow Coma Scale and the score defining severe head injury.

Eye opening (4), Verbal response (5), Motor response (6); total 3–15. GCS ≤8 defines severe head injury (and is the threshold for intubation/airway protection).

What is the classic CT appearance distinguishing an epidural from a subdural hematoma?

Epidural hematoma: biconvex/lentiform, does not cross suture lines, often from middle meningeal artery injury with a lucid interval. Subdural hematoma: crescent-shaped, crosses suture lines, from torn bridging veins.

What is the surgical treatment of choice for drug-resistant mesial temporal lobe epilepsy?

Anterior temporal lobectomy with amygdalohippocampectomy, after confirming a unilateral seizure focus (often hippocampal sclerosis) on EEG and MRI.

What is the most common solid renal tumor in adults and its classic triad?

Renal cell carcinoma (clear cell type most common). Classic triad (now uncommon, late presentation): flank pain, hematuria, and a palpable abdominal/flank mass.

What is the Gleason scoring system used for and what does it measure?

It grades prostate adenocarcinoma based on glandular architecture. The two most prevalent patterns (each 1–5) are summed for a score of 6–10; higher scores indicate poorer differentiation and worse prognosis (Grade Group system 1–5 now used).

What is the most common type of bladder cancer and its key risk factors?

Urothelial (transitional cell) carcinoma. Risk factors: cigarette smoking (most important), aromatic amines (aniline dye/rubber industry), cyclophosphamide; squamous cell type is linked to chronic Schistosoma haematobium infection.

Differentiate the management thresholds for ureteric stones by size.

Stones <5 mm usually pass spontaneously (conservative + medical expulsive therapy with alpha-blockers). 5–10 mm: trial of MET or ureteroscopy/ESWL. >10 mm or obstructing with infection: urgent intervention (ureteroscopy, PCNL, or decompression for infected obstructed system).

What is the procedure of choice for large (>2 cm) and staghorn renal calculi?

Percutaneous nephrolithotomy (PCNL) is the gold standard for large/staghorn stones; extracorporeal shock wave lithotripsy (ESWL) suits smaller (<2 cm) radiolucent/radio-opaque stones, and flexible ureteroscopy for lower-pole or moderate stones.

In renal transplantation, where is the donor kidney placed and to which vessels is it anastomosed?

Placed extraperitoneally in the iliac fossa (usually right). The renal artery anastomoses to the external/internal iliac artery, the renal vein to the external iliac vein, and the ureter to the bladder (Lich-Gregoir ureteroneocystostomy).

What is the reconstructive ladder in plastic surgery?

A stepwise approach to wound closure from simplest to most complex: secondary intention healing → primary closure → delayed primary closure → skin graft → tissue expansion → local flap → distant/free (microvascular) flap.

How is burn surface area estimated and what is the Parkland formula for fluid resuscitation?

Wallace 'rule of nines' (or Lund-Browder chart, most accurate in children) estimates TBSA. Parkland formula: 4 mL × body weight (kg) × %TBSA burned of Ringer's lactate in the first 24 h—half given in the first 8 hours from time of injury.