The effects of neurosurgical stress on peripheral lymphocyte subpopulations

To observe changes in the peripheral lymphocyte subpopulations as an index of cellular immunity during neurosurgical procedures.

Clinical study.

Operating room of a university hospital.

11 patients with early intracranial disease who were scheduled to undergo elective neurosurgery with general anesthesia. Patients in the control group (n = 10) underwent minor surgeries such as ophthalmologic, otorhinolaryngological, or orthopedic surgeries.

Blood was sampled before anesthesia induction (t0) for baseline and at 1 hour (t(1)) and 2 hours (t(2)) following surgical incision.

Detection and quantification of lymphocyte subpopulations were performed at each time point using single-label and double-label analyses of monoclonal antibodies against lymphocyte membrane surface markers.

Significant changes in patients who underwent a neurosurgical procedure included: the percentage of total T cells (CD3+) from 57.54 +/- 3.50% at t(0) to 51.41 +/- 4.26% at t(1) and 46.29 +/- 4.02% at t(2); the percentage of inducer T cells (CD4+, Leu8+) from 27.39 +/- 2.26% at t(0), to 23.26 +/- 2.30% at t(1) and 20.82 +/- 2.70% at t(2); the CD4/CD8 ratio, from 1.78 +/- 0.25% at t(0) to 1.35 +/- 0.12% at t(1) and 1.22 +/- 0.17% at t(2). The percentage of suppressor T cells (CD8+, Leu15+) increased significantly from 10.8 +/- 1.07% at t(0) to 13.64 +/- 1.62% at t(1), and 14.82 +/- 1.24% at t(2). The percentages of the natural killer cell subsets also increased significantly. Control group patients who underwent minor surgeries showed no significant changes.

Neurosurgery-induced significant suppression of cellular immunity was demonstrated in peripheral lymphocyte subpopulations, probably from the surgical stress on the central nervous system.