CD4 and susceptibility to pneumonia measurement: Therefore, in this study, we analyzed the changes of the IGF-1, CD4+ T cells, CD8+ T cells, PCT, CRP, leukocyte and various inflammatory cytokines, and compared the cure time of pneumonia, intracranial infection and urinary tract infection, aiming to investigate the role of GH treatment in improving severe neurosurgical patients’ prognosis.