Laparoscopy

Insufflation of abdominal cavity with CO~2</sub,> in order to facilitate intra-abdominal surgery.

Physiology

Key changes:

  • Respiratory
    • Limited diaphragmatic excursion
      • Elevated airway pressure
      • ↓ pulmonary compliance
      • Atelectasis
    • ↑ PaCO2
      Due to absorption of insufflated CO2.
  • Cardiovascular
    Effects vary depending on intraabdominal pressure, and these changes will be exacerbated by changes in positioning altering venous return:
    • IAP ⩽10mmHg
      • Splanchnic compression and autotransfusion
        Up to 40% reduction in mesenteric blood flow.
      • ↑ Preload, VR, and CO
    • IAP 10-20mmHg
      • IVC compression and ↓ preload
      • ↑ SVR
      • ↑ SVR exceeds ↓ preload; so BP is maintained
    • IAP >20mmHg
      • ↑ IVC compression and ↓↓ preload
      • ↑ SVR
        Inotropes more effective than vasopressors in management of hypotension.
      • ↓ CO with ↓ in BP

Benefits

Include:

  • Reduced incision size
    • Improved post-operative pain
    • ↓ recovery time
    • ↓ post-operative infections

Risks and Contraindications

Patient:

  • Raised ICP
    Due to ↑ PaCO2.
  • Severe hypovolaemia
  • Right-to-left shunts
    ↑ passage with raised venous pressures.

Surgical:

  • Organ injury
    • Vascular
    • Bowel
    • Ureteric
    • Venous gas embolism
  • Positioning
    • Movement
    • Cerebral oedema/hypoperfusion

Anaesthesia:

  • Generally requires ETT
    LMA use controversial.
  • ↑ PONV

References

  1. Hayden P, Cowman S. Anaesthesia for laparoscopic surgery. Contin Educ Anaesth Crit Care Pain. 2011 Oct 1;11(5):177–80.