MSC - F. Surgery Answers 2025

o Tenesmus (feeling of incomplete defecation).

oMucus in stool (rectal inflammation).

Systemic signs: Fever, malaise, chills.

Physical Examination

Abdominal exam:

oSuprapubic tenderness (may mimic cystitis).

Digital Rectal Exam (DRE):

oBulging, tender anterior rectal wall (key diagnostic sign).

Vaginal Exam (in women):

oTenderness in posterior fornix.

Diagnosis

1. Laboratory Findings:

o Leukocytosis (↑ WBC with left shift).

o↑ CRP, ESR.

2.Imaging:

oUltrasound (Transabdominal/Transrectal):

 Hypoechoic fluid collection in the pelvis.

oCT (Gold Standard):

Fluid collection with rim enhancement in the rectovesical/rectouterine pouch.

oMRI (if CT unavailable or for better soft-tissue detail).

3.Diagnostic Puncture:

oTransrectal or transvaginal US-guided aspiration → pus confirms abscess.

Treatment

1.Antibiotic Therapy

Empirical IV antibiotics (cover enteric Gram-negatives + anaerobes): o Ceftriaxone + Metronidazole (or Piperacillin-Tazobactam).

Adjust based on culture results.

2.Drainage (Definitive Treatment)

Indications: Abscess >3 cm or failed medical therapy.

Methods:

o Transrectal Drainage (most common):

 US-guided needle puncture → insertion of drainage catheter.

oTransvaginal Drainage (in women):

Via posterior fornix puncture.

oPercutaneous CT-guided Drainage (if other routes inaccessible).

3.Surgical Drainage (Rarely Needed)

Laparoscopic/open drainage if:

oMultiloculated abscess.

oFailure of minimally invasive methods.

4.Delayed Appendectomy

Elective appendectomy after 6–8 weeks (if appendix not removed initially).

Complications

Sepsis (if untreated).

Fistula formation (rectal, vaginal, or bladder).

Recurrent abscess (incomplete drainage).

1.Access (Incision)

Volkovich-Dyakonov-McBurney incision (oblique, muscle-splitting in RLQ).

Alternative: Laparoscopic approach (if feasible).

2.Layer-by-Layer Dissection

Open external oblique aponeurosis, split internal oblique & transversus muscles.

Incise peritoneum to enter the abdominal cavity.

3.Identify & Expose the Cecum

Deliver the cecum into the wound.

Locate the base of the appendix (may require adhesiolysis).

4.Place Purse-String Suture

3-0 absorbable suture (e.g., Vicryl) around the appendix base on the cecum.

5.Ligate & Divide the Appendix Base

Ligate the base with absorbable suture (e.g., Catgut/Vicryl).

Clamp with Kocher forceps distal to the ligature.

Transect the appendix (leave a short stump).

Disinfect stump with iodine/povidone.

6.Invert the Stump

Tighten the purse-string suture to bury the stump.

Reinforce with a Z-stitch (Lembert suture) for secure closure.

7.Ligate the Mesoappendix (Retrograde)

Grasp the distal appendix with a clamp and apply traction.

Serially clamp, ligate, and divide the mesentery from base to tip.

8.Final Steps

Check hemostasis.

Irrigate the surgical site (if infection suspected).

Close the abdomen in layers:

o Peritoneum → muscle → fascia → skin.

Key Points

Advantage: Safer when the appendix is immobile or retroperitoneal.

Critical Steps:

Secure base ligation to prevent fecal fistula.

Complete mesentery ligation to avoid bleeding.

Post-Op: Monitor for stump leak or abscess (rare but serious).

11. Differential diagnosis of acute appendicitis and perforated gastric ulcer.

Key Clinical Differences

Critical Diagnostic Clues

1. Pain Migration

o Appendicitis: Periumbilical → RLQ (Kocher’s sign).

oPerforated ulcer: Epigastric → diffuse (due to chemical peritonitis).

2.Abdominal Rigidity

oAppendicitis: Localized RLQ guarding.

oPerforated ulcer: Global rigidity (entire abdomen "like a board").

3.Imaging

oX-ray/CT: Free subdiaphragmatic air (pathognomonic for perforation).

oUltrasound: RLQ appendix dilation (>6 mm), periappendiceal fluid.

4.Ancillary Signs

o Obturator/Psoas signs (appendicitis).

o Liver dullness loss (perforation, but late sign).

Pitfalls & Mimics

Late Presentation: Both conditions → generalized peritonitis (obscures origin).

Atypical Anatomy:

o Retrocecal appendicitis → flank/back pain (mimics renal colic).

oPelvic appendix → urinary symptoms (dysuria, tenesmus).

Perforated Duodenal Ulcer: Fluid tracks to RLQ (mimics appendicitis).

Management Approach

1.Uncertain Diagnosis → CT abdomen/pelvis (gold standard).

2.Surgical Planning:

o Appendicitis: RLQ incision (McBurney) or laparoscopy.

oPerforated ulcer: Upper midline laparotomy (for repair + washout).

3.Intraoperative Surprise:

oIf RLQ incision reveals no appendicitis → convert to midline laparotomy.

Takeaway

Sudden epigastric pain + rigidity → Think perforation (image for free air).

Migrating RLQ pain + fever → Think appendicitis.

Always consider ulcer perforation in RLQ peritonitis (especially with prior dyspepsia).

External abdominal hernias

1. External abdominal hernias. The concept, elements of hernia and classification.

Definition

An external abdominal hernia is the abnormal protrusion of intra-abdominal organs (covered by parietal peritoneum) through a weak spot in the abdominal or pelvic wall.

Internal hernias occur when organs enter peritoneal recesses (e.g., paraduodenal) or the thoracic cavity (e.g., diaphragmatic hernia).

Elements of a Hernia

1. Hernial Orifice

oThe defect in the musculoaponeurotic layer (e.g., inguinal canal, femoral ring).

2.Hernial Sac

oA pouch of parietal peritoneum protruding through the orifice.

oParts:

Neck (narrow part at the orifice).

Body (main expanded portion).

Fundus (distal end).

3.Hernial Contents

oCommon: Omentum, small bowel loops.

oSliding Hernia: Organs partially covered by peritoneum (e.g., bladder, cecum, ascending colon).

Classification of External Abdominal Hernias

1. By Anatomical Location