7. Significance of Minimally Invasive Surgery, Common Surgical Techniques

I. Basic Concept and Significance

• Minimally invasive surgery (MIS): Operative techniques performed with less access trauma than conventional open surgery
• Usually uses small incisions, trocars, endoscopes/cameras, long instruments and image guidance
• Main forms → Laparoscopic, thoracoscopic, robotic-assisted, endoscopic, percutaneous image-guided procedures
• Goal → Same therapeutic result as open surgery with smaller operative trauma
• Modern principle → Use MIS when it is technically possible, oncologically safe and beneficial for the patient

Why MIS Is Important

• Reduces surgical access trauma → Less tissue injury and inflammatory response
• Improves postoperative recovery → Less pain, earlier mobilization, shorter hospital stay
• Reduces wound-related morbidity → Less wound infection, dehiscence and incisional hernia
• Supports ERAS principles → Early feeding, early mobilization, faster rehabilitation
• In oncology → Faster recovery may allow earlier adjuvant oncological treatment
• Magnified camera view can improve visualization of fine anatomy

II. Laparoscopic Surgery

• Laparoscopy: Minimally invasive access to the peritoneal cavity using camera and instruments through trocars
• Requires adequate working space, visualization and safe access
• Most common gas → CO2 because it is non-flammable, soluble and rapidly absorbed

Laparoscopic Procedure: Main Steps

1. General anesthesia
2. Patient positioning according to operation
3. Access to peritoneal cavity
4. Creation of pneumoperitoneum
5. Camera insertion and diagnostic inspection
6. Placement of additional working ports
7. Dissection, hemostasis, resection/reconstruction
8. Specimen retrieval in a bag when needed
9. Desufflation, port removal and wound closure

Access Methods

• Closed technique → Veress needle insertion → CO2 insufflation → trocar insertion
• Open technique / Hasson technique → Small incision, direct entry, blunt trocar under vision
• Optical trocar → Entry under direct visual control
• Access choice depends on previous operations, obesity, pregnancy, adhesions and surgeon experience

Pneumoperitoneum

• CO2 insufflation increases intra-abdominal pressure → Abdominal wall elevates → Working space created
• Usual pressure often around 12-15 mmHg in adults, lower if patient condition requires
• Physiological effects → Increased intra-abdominal pressure + CO2 absorption

• Respiratory → Diaphragm elevation, reduced lung compliance, possible hypercapnia
• Cardiovascular → Reduced venous return at high pressure, increased afterload, arrhythmia risk in susceptible patients
• Renal/splanchnic → Reduced perfusion if pressure is high/prolonged

Visualization and Instrumentation

• Laparoscope inserted through trocar → Image transmitted to monitor
• Camera provides magnified view, usually 2D in conventional laparoscopy
• Working instruments inserted through separate ports
• Energy devices → Monopolar/bipolar cautery, ultrasonic shears, vessel sealing devices
• Conversion to open surgery is not a complication by itself → It is a safety decision when MIS is unsafe/inadequate

III. Advantages, Limitations and Contraindications

Advantages

• Small wounds and scars → Better cosmetic result
• Less wound contamination and lower wound infection risk
• Less wound-healing disorder and lower incisional hernia risk
• Less postoperative pain → Less opioid need
• Earlier mobilization → Lower risk of DVT/PE, atelectasis and pneumonia
• Faster recovery and rehabilitation
• Shorter hospitalization and earlier return to normal activity/work
• Less intraoperative blood loss in many procedures
• Magnified view → Better visualization of anatomy in selected operations
• Earlier start of adjuvant oncological therapy may be possible after faster recovery

Disadvantages / Limitations

• 2D image in conventional laparoscopy → Loss of normal depth perception
• No direct palpation/tactile feedback
• Restricted instrument movement and fulcrum effect
• Longer operation time during learning curve or complex cases
• Requires special equipment and trained surgical/anesthetic team
• Higher cost in some settings, especially robotic surgery
• Difficult in severe adhesions, massive obesity, advanced inflammation, bowel distension or bleeding
• Risk of access injuries → Bowel, vessel, bladder injury
• Risk from pneumoperitoneum → Hypercapnia, cardiopulmonary stress, gas embolism very rare
• Conversion to open surgery may be necessary

Contraindications

• Absolute/near absolute → Hemodynamic instability, inability to tolerate general anesthesia/pneumoperitoneum, uncontrolled coagulopathy
• Cardiorespiratory insufficiency → Severe COPD, severe heart failure, pulmonary hypertension or poor reserve may not tolerate CO2 pneumoperitoneum
• Advanced pregnancy → Third trimester is difficult because of uterine size and altered physiology; laparoscopy may still be possible in expert hands when necessary
• Portal hypertension / severe cirrhosis → Bleeding risk, varices, coagulopathy, ascites
• Surgical contraindications → Severe bowel distension, diffuse peritonitis in unstable patient, extensive adhesions after multiple operations, huge tumor, unclear anatomy

• Many contraindications are relative → Decision depends on urgency, disease, patient condition and local expertise

IV. Common Minimally Invasive Surgical Techniques

1. Laparoscopic Abdominal Surgery

• Standard/very common procedures → Cholecystectomy, appendectomy, diagnostic laparoscopy
• Hernia repair → Inguinal TAPP/TEP, ventral/incisional hernia repair in selected cases
• Upper GI → Anti-reflux surgery, hiatal hernia repair, Heller myotomy, gastrectomy in selected cases
• Bariatric surgery → Sleeve gastrectomy, gastric bypass
• Colorectal → Colectomy, rectal resection, inflammatory bowel disease surgery, colorectal cancer surgery
• Solid organs/endocrine → Adrenalectomy, splenectomy, nephrectomy, selected liver and pancreatic procedures
• Emergency surgery → Appendicitis, perforated ulcer, selected obstruction/adhesiolysis, selected trauma/staging cases

2. Robotic-Assisted Surgery

• Surgeon controls robotic arms from a console
• Advantages → 3D vision, tremor filtering, articulated instruments, improved precision in narrow spaces
• Limitations → Cost, setup time, need for special training, limited availability
• Common uses → Prostatectomy, gynecologic oncology, rectal cancer surgery, hiatal hernia repair, bariatric/upper GI surgery in selected centers

3. Thoracoscopic Surgery / VATS

• VATS: Video-assisted thoracoscopic surgery through small thoracic ports
• Used for → Lung wedge resection, lobectomy, pleural biopsy, pleurodesis, pneumothorax repair, thymectomy, mediastinal procedures
• Advantages → Less pain than thoracotomy, better respiratory recovery, shorter hospital stay

4. Endoscopic Surgery

• Uses natural orifices and flexible/rigid endoscopes
• Diagnostic and therapeutic in GI tract, airway, urinary tract and other hollow organs
• GI examples → Polypectomy, endoscopic hemostasis, EMR/ESD, ERCP with sphincterotomy/stone extraction/stent, PEG placement
• Other examples → Bronchoscopy interventions, cystoscopic stone/tumor procedures, hysteroscopy

5. Image-Guided Percutaneous / Interventional Radiology Techniques

• Performed through needle/catheter access under ultrasound, CT, fluoroscopy or angiographic guidance
• Examples → Percutaneous biopsy, abscess drainage, nephrostomy, biliary drainage/stenting, angioplasty/stenting, embolization of bleeding or tumors, tumor ablation
• Important in surgery because they can avoid or delay major operation and provide source control/diagnosis

6. NOTES and Single-Incision Techniques

• NOTES: Natural orifice transluminal endoscopic surgery, e.g. transvaginal or transgastric access
• Concept → Avoid visible abdominal incisions
• Currently limited/selected use; partly experimental depending on indication and center
• SILS / single-incision laparoscopy → One umbilical incision; better cosmetic result but technically harder