title: Immune cell populations decrease during craniotomy under general anesthesia.
abstract: BACKGROUND
  Postoperative infections are common and potentially fatal complications in neurosurgical intensive care medicine. An impairment of immune function after central nervous system surgery is associated with higher risk of infection and postoperative complications. The aim of our study was to investigate how the immune cell population changes during the anesthesia process in patients undergoing craniotomy surgery.
  
  
  METHODS
  Patients undergoing craniotomy who had an inhaled general anesthetic were studied. Blood samples were collected before anesthesia and 30, 45, 60, 120, and 240 minutes after anesthesia began. Blood counts for neutrophils, monocytes, and lymphocytes were determined along with lymphocyte subpopulations (T cells, inducer and helper T cells, suppressor and cytotoxic T cells, natural killer cells, and B cells). Plasma concentrations of interleukin (IL)-2, IL-4, IL-6, and IL-10 were also measured along with tumor necrosis factor-α and interferon-γ. Data were analyzed by SPSS 13.0 software using repeated-measures analysis of variance followed by a Bonferroni correction.
  
  
  RESULTS
  Eighteen patients were enrolled in this study. In the comparison of the immune cell counts during neuroanesthesia, we found that at 30 minutes after anesthesia induction, neutrophils, monocytes, and lymphocytes decreased 18% (95% confidence interval [CI]: 11.0%-24.6%), 34% (95% CI: 16.2%-51.1%), and 39% (95% CI: 29.0%-48.9%) compared with their levels before anesthesia. At extubation the neutrophils returned to the base level. It also showed that natural killer cells decreased significantly during anesthesia. The concentration of cytokines in peripheral blood did not change significantly.
  
  
  CONCLUSIONS
  Our results showed that anesthesia and surgery upset the balance of the immune system during craniotomy, and a significant decrease in immune cell populations emerged after induction under general anesthesia.
authors.affiliation: Capital Medical University, Laboratory Diagnosis Center, Beijing Tiantan Hospital, No.6 Tiantan Xili, Chongwen Men District, Beijing, 100050, China.
authors.forename: Shujing
authors.initials: S
authors.lastname: Liu
authors.forename: Baoguo
authors.initials: B
authors.lastname: Wang
authors.forename: Shuqin
authors.initials: S
authors.lastname: Li
authors.forename: Yali
authors.initials: Y
authors.lastname: Zhou
authors.forename: Lixin
authors.initials: L
authors.lastname: An
authors.forename: Yajie
authors.initials: Y
authors.lastname: Wang
authors.forename: Hong
authors.initials: H
authors.lastname: Lv
authors.forename: Guojun
authors.initials: G
authors.lastname: Zhang
authors.forename: Fang
authors.initials: F
authors.lastname: Fang
authors.forename: Zhizhong
authors.initials: Z
authors.lastname: Liu
authors.forename: Ruquan
authors.initials: R
authors.lastname: Han
authors.forename: Tao
authors.initials: T
authors.lastname: Jiang
authors.forename: Xixiong
authors.initials: X
authors.lastname: Kang
mesh_terms: D000328:Adult; D000704:Analysis of Variance; D000768:Anesthesia, General / Q000009:adverse effects*; D018685:Anesthetics, Inhalation / Q000009:adverse effects*; D002681:China; D003399:Craniotomy / Q000009:adverse effects*; D017558:Elective Surgical Procedures; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D056747:Immunomodulation / Q000187:drug effects*; D007371:Interferon-gamma / Q000097:blood; D007378:Interleukins / Q000097:blood; D007958:Leukocyte Count; D007962:Leukocytes / Q000187:drug effects* / Q000276:immunology; D016131:Lymphocyte Subsets / Q000187:drug effects; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000187:drug effects; D009504:Neutrophils / Q000187:drug effects; D013997:Time Factors; D014409:Tumor Necrosis Factor-alpha / Q000097:blood
chemical_list: D018685:Anesthetics, Inhalation; D007378:Interleukins; D014409:Tumor Necrosis Factor-alpha; D007371:Interferon-gamma