title: Postoperative host responses in elderly patients after gastrointestinal surgery.
abstract: OBJECTIVE
  The age-associated dysregulation of hemodynamic, metabolic and immune responses contributes to the high incidence of complications after major abdominal surgery.
  
  
  METHODS
  Ninety-five patients who underwent gastric resection (n=51) and colorectal resection (n=44) were divided according to age into Groups A (n=45, less than 70 years old), B (n=30, 70-79 years) and C (n=20, over 80 years). Flow cytometric analysis of CD4+ lymphocytes for interferon (IFN)-gamma and interleukin (IL)-4 production determined the Th1/2 balance. Energy expenditure was measured by indirect calorimetry, and hemodynamics were studied using pulse dye densitometry.
  
  
  RESULTS
  Surgical procedures, operating time, blood loss and morbidity did not significantly differ among the three groups. The cardiac index (CI) in group A and B increased significantly over preoperative levels until POD 3, but there were no significant perioperative changes in the CI levels of group C. Resting energy expenditure levels changed similarly to those of CI. The postoperative Th1/2 ratio decreased from young to elderly to very elderly patients, although no differences were significant before surgery. The postoperative percentage of CD4+IFN-gamma +T cells (Th1) in group C decreased significantly despite of no significant changes in that of group A and B. In contrast, the ratio of CD4+IL-4+T cells (Th2) in the all groups significantly increased after surgery.
  
  
  CONCLUSIONS
  Host responses in elderly patients after major abdominal surgery were more hyperdynamic and hypermetabolic than those of young patients. Postoperative dysregulation of the Th1/2 balance was also associated with aging. However, host responses appear to significantly differ between elderly and very elderly patients.
authors.affiliation: Department of Surgery, National Kochi Hospital, Japan. masa1192@tokushima-med.jrc.or.jp
authors.forename: M
authors.initials: M
authors.lastname: Ishikawa
authors.forename: M
authors.initials: M
authors.lastname: Nishioka
authors.forename: N
authors.initials: N
authors.lastname: Hanaki
authors.forename: T
authors.initials: T
authors.lastname: Miyauchi
authors.forename: Y
authors.initials: Y
authors.lastname: Kashiwagi
authors.forename: Y
authors.initials: Y
authors.lastname: Kawasaki
authors.forename: H
authors.initials: H
authors.lastname: Miki
authors.forename: H
authors.initials: H
authors.lastname: Kagawa
authors.forename: H
authors.initials: H
authors.lastname: Ioki
authors.forename: Y
authors.initials: Y
authors.lastname: Nakamura
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D016063:Blood Loss, Surgical; D001810:Blood Volume; D002153:Calorimetry, Indirect; D002302:Cardiac Output; D003082:Colectomy; D004734:Energy Metabolism; D005260:Female; D005434:Flow Cytometry; D005743:Gastrectomy; D006801:Humans; D007371:Interferon-gamma / Q000378:metabolism; D015847:Interleukin-4 / Q000378:metabolism; D018655:Lymphocyte Count; D008297:Male; D008875:Middle Aged; D011184:Postoperative Period; D018417:Th1 Cells; D018418:Th2 Cells
chemical_list: D015847:Interleukin-4; D007371:Interferon-gamma