Surgical Principles and Basic Sciences
Core concepts
This domain underpins every procedure: asepsis, hemostasis, tissue handling, suture selection, wound healing biology, and anesthesia/analgesia principles. Understand the surgical triangle (surgeon, patient, environment), sterilization versus disinfection, and the classification of surgical wounds (clean, clean-contaminated, contaminated, dirty). Know suture materials by behavior (absorbable vs nonabsorbable, monofilament vs multifilament), tensile strength loss, and appropriate tissue matching.
Traps to expect
Questions often test the 'least reactive' or 'most appropriate' suture for a given tissue. Monofilament absorbable (e.g., poliglecaprone) for contaminated fields; nonabsorbable monofilament for skin or tendon. Watch for confusion between hand ties and instrument ties, or between different suture patterns (simple interrupted vs continuous vs cruciate). Hemostasis questions may test the coagulation cascade or the difference between ligation and electrocautery. Fluid therapy and pain management (multimodal analgesia) appear as integrated concepts.
Worked example
A contaminated abdominal wound requires closure. The trap is selecting braided nonabsorbable suture. The correct reasoning: multifilament materials harbor bacteria; choose monofilament absorbable suture and avoid excessive tension. Rule of thumb: match suture to tissue, minimize reactivity, and never place nonabsorbable multifilament in a contaminated field.
Exam strategy
Reason from first principles: perfusion, tension, contamination, and tissue behavior. These generalize across species and procedures.