MSC - F. Surgery Answers 2025
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3.Closure of diaphragmatic defect with non-absorbable sutures
4.Use of mesh for large defects
5.In traumatic cases, repair other injured structures
19.Mediastinitis. Etiopathogenesis of acute purulent mediastinitis, clinic, diagnosis, treatment.
Mediastinitis is an inflammation of the mediastinal tissue, often purulent, with a high mortality rate if untreated. It can be primary (due to trauma or surgery) or secondary (spread from adjacent infections).
Etiopathogenesis
Common Causes:
1.Odontogenic and maxillofacial infections (most frequent): o Phlegmons of:
Peripharyngeal space (1)
Root of the tongue (2)
Floor of the mouth (3)
Submandibular region (4)
Posterior maxillary region (5)
2.Spread pathways:
oFrom peripharyngeal space/tongue root → retropharyngeal space → posterior mediastinum (along esophagus and pharynx).
oFrom submandibular/posterior maxillary regions → along the neurovascular bundle of the neck → anterior mediastinum.
3.Other causes:
oEsophageal perforation (endoscopy, foreign bodies, trauma).
o Postoperative (sternotomy, cardiac surgery).
o Hematogenous/metastatic spread (rare).
Clinical Presentation
General Symptoms:
High fever (39–40°C), chills, tachycardia.
Severe intoxication (weakness, headache, confusion).
Forced sitting position (relieves pain and dyspnea).
Local Symptoms:
1. Anterior Mediastinitis:
oRetrosternal pain (worsens with head tilting back, sternal percussion).
oInflammatory infiltrate along the neurovascular bundle (jugular fossa, supraclavicular region).
o Ravich-Scherbo sign: Jugular tissue retraction during inspiration.
o Dyspnea (40–50 breaths/min).
o Cough (due to vagus nerve irritation).
oSuperior vena cava syndrome (facial edema, cyanosis, venous distension).
2.Posterior Mediastinitis:
oDeep chest pain (radiates to interscapular/epigastric regions).
o Pain on swallowing (odynophagia).
o Hoarseness (recurrent laryngeal nerve involvement).
o Dysphagia (esophageal compression).
Diagnosis
1. Imaging:
oX-ray/CT: Widened mediastinum, pleural effusion, gas bubbles (anaerobic infection).
o Esophagoscopy/Bronchoscopy: If perforation suspected.
o Ultrasound/CT-guided aspiration: For microbiological analysis.
2. Lab Tests:
o Leukocytosis (↑WBC, left shift).
o Blood cultures (sepsis screening).
Treatment
1. Surgical Drainage (Mediastinotomy)
Anterior Mediastinitis:
o Cervical approach (along sternocleidomastoid muscle).
o Suprasternal approach (Razumovsky) for upper mediastinum.
oTranssternal drainage if deeper involvement.
Posterior Mediastinitis:
oCervical mediastinotomy (along the esophagus).
o Thoracotomy (Dobrosmyslov approach) if extensive.
oTransabdominal (Savinykh approach) for lower mediastinum.
2.Antibiotics & Supportive Therapy:
Broad-spectrum IV antibiotics (covering anaerobes, Gram ±):
oCarbapenems/Cephalosporins + Metronidazole + Aminoglycosides.
Detoxification (IV fluids, plasmapheresis if severe).
Nutritional support (NG tube/TPN if esophageal injury).
3.Postoperative Care:
Continuous irrigation/aspiration (double-lumen drains).
Analgesia (opioids + NSAIDs).
Immunomodulation (IVIG, plasma transfusions).
Complications
Sepsis, pleural empyema, pericarditis, ARDS.
Mortality: 30–50% if delayed treatment.
Key Takeaways
Early surgical drainage is critical.
CT is the gold standard for diagnosis.
Multidisciplinary approach (surgery + ID + ICU).
Prognosis: Depends on timely intervention and infection control.
Diseases of the biliary tract
1. Classification of diseases of the biliary tract. Cholelithiasis. Etiopathogenesis of cholelithiasis.
Classification of Diseases of the Biliary Tract
I.Cholelithiasis Not Complicated by Infection
1.Hepatic colic (biliary colic)
2.Valvular stone of the common bile duct (CBD) — intermittent obstruction
3.Wedged (impacted) choledochal stone — complete obstruction
II.Cholelithiasis Complicated by Infection (Acute Calculous Cholecystitis)
1.Catarrhal
2.Phlegmonous
3.Gangrenous
4.Perforated
III.Acalculous Acute Cholecystitis
1.Catarrhal
2.Phlegmonous
3.Gangrenous
4.Perforated
5.Enzymatic (due to reflux of pancreatic enzymes)
IV. Complications of Cholecystitis
1.Cholangitis (ascending infection of the biliary tree)
2.Sepsis
3.Peritonitis
4.Pancreatitis
5.Hepatitis
V. Dyskinesia of the Biliary Tract
Functional motility disorders without anatomical obstruction (hyperkinetic or hypokinetic)
Etiopathogenesis of Cholelithiasis (Gallstone Disease)
Types of Gallstones:
1.Cholesterol stones (80%)
2.Pigment stones (black or brown — calcium bilirubinate)
3.Mixed stones
Risk Factors (The “4 F’s” + more)
Female
Forty (age > 40)
Fat (obesity or rapid weight loss)
Fertile (pregnancy, estrogen)
Others: hemolytic anemia (pigment stones), cirrhosis, ileal disease (interferes with bile salt reabsorption), TPN, diabetes
Pathogenesis:
1.Cholesterol supersaturation of bile
2.Gallbladder hypomotility → stasis
3.Increased mucin secretion → nucleation of crystals
4.Infection or inflammation → promotes stone formation (especially pigment stones)
2.Methods of examination of patients with diseases of the biliary tract.
Methods of Examination in Biliary Tract Diseases (Brief)
1. Ultrasound (USG)
o First-line, non-invasive.
o Detects gallstones with 98–100% accuracy.
oAssesses gallbladder wall thickness and bile duct dilation.
2.Percutaneous Transhepatic Cholangiography (PTC)
oUsed in prolonged jaundice.
o Contrast injected directly into intrahepatic bile ducts.
o Diagnoses obstruction; allows external bile drainage.
oInvasive but highly informative.
3.Endoscopic Retrograde Cholangiopancreatography (ERCP)
oGold standard for bile duct pathology.
o Diagnoses and treats stones, strictures, tumors.
oInvasive; risk of pancreatitis.
4.Computed Tomography (CT)
oDetects stones, tumors, wall thickness, duct dilation.
oHigh accuracy; used in complex or suspected malignancy cases.
5.Intraoperative Diagnostics a. Intraoperative Ultrasound
Direct ultrasound probe during surgery for bile duct visualization. b. Palpation
Surgeon manually examines bile ducts and pancreatic head for stones or masses.
c.Intraoperative Cholangiography
Catheterization of the common bile duct.
Injection of 10–20 ml contrast.
Real-time fluoroscopy to detect stones or strictures.
d.Biliary Duct Bougie Examination
Passing of metal bougie through bile duct into duodenum.
Helps assess duct patency and papilla size (~3 mm).
e.Choledochoscopy
Introduction of fiberoptic scope into bile duct.
Direct visualization and removal of stones.
6. Plain Abdominal X-ray
o Limited use.
oDetects calcified stones and gas in biliary system (suggests infection or fistula).
7.Peroral and Intravenous Cholecystography
oContrast studies to visualize gallbladder and bile ducts.
oRarely used now; limited by low contrast concentration and unsuitability in jaundice.
3.Intraoperative examination of the biliary tract.
Intraoperative Diagnostics
a. Intraoperative Ultrasound
Direct ultrasound probe during surgery for bile duct visualization.
b.Palpation
Surgeon manually examines bile ducts and pancreatic head for stones or masses.
c.Intraoperative Cholangiography
Catheterization of the common bile duct.
Injection of 10–20 ml contrast.
Real-time fluoroscopy to detect stones or strictures.
d.Biliary Duct Bougie Examination
Passing of metal bougie through bile duct into duodenum.
Helps assess duct patency and papilla size (~3 mm).
e.Choledochoscopy
Introduction of fiberoptic scope into bile duct.
Direct visualization and removal of stones.
4. Methods and means of contrast X-ray diagnostics of diseases of the biliary tract.
Contrast X-ray Diagnostics of the Biliary Tract
2.Peroral Cholecystography
Patient ingests oral iodinated contrast agents (e.g., bilitrast, iopagnost).
Contrast absorbed via GI tract, excreted in bile, accumulates in gallbladder.
X-rays taken 15-17 hours later; function assessed after fatty meal.
Limitations: Only visualizes gallbladder, not ducts; not suitable in jaundice or post-cholecystectomy.
Practically obsolete due to ultrasound superiority.
3.Intravenous Cholecystography (IV Cholangiography)
Intravenous injection of iodine-containing contrast agents (e.g., bilignost, biligrafin).
Radiographs at multiple intervals post-injection (15, 25, 45, 60, 90, 120 minutes).
Visualizes gallbladder and bile ducts.
Requires allergy testing for iodine.
Limited use due to poor ductal contrast and contraindicated in jaundice or absent gallbladder.
4.Percutaneous Transhepatic Cholangiography (PTC)
Contrast injected directly into dilated intrahepatic bile ducts via needle puncture under ultrasound guidance.
Highly informative for level and nature of obstruction (stones, tumors, strictures).
Allows external biliary drainage in obstructive jaundice.
Invasive but critical for patients with prolonged jaundice when ERCP is not feasible.
5.Endoscopic Retrograde Cholangiopancreatography (ERCP)
Endoscopic catheterization of the major duodenal papilla.
Contrast injected retrogradely into bile and pancreatic ducts.
Visualizes ductal anatomy, strictures, stones, tumors.
Enables therapeutic interventions (stone extraction, stenting).
Most informative and commonly used invasive contrast method.
Risks include pancreatitis and perforation.
6.Laparoscopic Cholangiography
During laparoscopy, gallbladder is punctured, and contrast injected.
Visualizes gallbladder and biliary tree under direct vision.
Used intraoperatively to detect stones or anatomical anomalies.
Contrast Agents
Iodine-based agents (e.g., biligranin, bilignost) used for intravenous and oral studies.
Water-soluble contrast media used for PTC and ERCP.
Allergy testing necessary for iodine-containing agents.
Heating contrast agents to body temperature reduces patient discomfort during injection.
5.Billiary colic. Clinic, diagnosis, outcomes. Treatment and surgical tactics for hepatic colic.
Biliary colic is a transient, intense, visceral pain caused by the temporary obstruction of the cystic duct or occasionally the common bile duct by gallstones. It results from gallbladder contraction against an impacted stone, increasing intraluminal pressure.
Clinical Presentation (Clinic)
Pain:
oSudden onset of steady, severe pain localized to the right upper quadrant (RUQ) or epigastrium.
o Often radiates to the right scapular tip or the back.
oTypically occurs postprandially, especially after fatty meals, usually within 30 minutes to 1 hour.
oDuration: Usually lasts 30 minutes to 5 hours, then subsides as the stone dislodges or the gallbladder relaxes.
oPain is constant, dull or colicky, not relieved by bowel movements, antacids, or positional changes.
Associated symptoms:
oNausea and vomiting
o Diaphoresis