Natural killer cell activity during premedication, anaesthesia and surgery

Area of Science:

• Immunology
• Surgical Oncology

Background:

• Natural killer (NK) cells are crucial for innate immunity.
• Surgical procedures and anesthesia can modulate immune function.

Purpose of the Study:

• To investigate the impact of premedication, anesthesia, and surgery on NK cell activity.
• To assess the temporal changes in NK cell activity during and after total hip replacement.

Main Methods:

• Peripheral blood mononuclear cells (PBMCs) from eight patients undergoing hip replacement were analyzed.
• NK cell activity was measured using a 51Cr release assay against K-562 target cells.
• Blood samples were collected consecutively throughout the perioperative period.

Main Results:

• Premedication with diazepam significantly increased NK cell activity.
• Anesthesia and surgery further elevated NK cell activity, which remained high during the procedure.
• Postoperatively, NK cell activity decreased significantly and remained depressed for at least 5 days.

Conclusions:

• Premedication, anesthesia, and surgery induce a transient increase in NK cell activity.
• Postoperative depression of NK cell activity may be linked to cell redistribution.
• The clinical implications of these NK cell alterations require further investigation.