Defining the Term "Elderly" in the Field of Surgery: A Retrospective Study Regarding the Changes in the Immunoinflammatory Indices During the Immediate Perioperative Period of the Elective Uncomplicated Laparoscopic Cholecystectomy.

Backgrounds: The term "elderly" seems to have been used as "vulnerable to various stresses" but not well defined. To define the "elderly", we investigated whether the increased age causes unfavorable changes in several immunoinflammatory indices that indicate the increased vulnerability in the surgical field.

Patients And Methods: One-hundred forty-two patients undergoing an elective-uncomplicated laparoscopic cholecystectomy (within 60 min and without intraoperative-cholangiography, bile spillage, or open conversion) were retrospectively investigated. Before surgery, immediately after surgery, and on postoperative day (POD)1, whether the patient age correlated the following variables was examined: neutrophil-to-lymphocyte ratio (NLR), lymphocyte-to-monocyte ratio, platelet-to-lymphocyte ratio, lymphocyte-to-C-reactive-protein ratio (LCR), C-reactive-protein-to-albumin ratio (CAR), and others.

Results: The immunoinflammatory indices most unfavorably changed on POD1. The age correlated neither lymphocyte-to-monocyte ratio nor platelet-to-lymphocyte ratio on POD1, when NLR, LCR, and CAR showed the significant correlation with the age. Multiple regression analyses determined the following variables as the independent determinants of these 3 indices on POD1: age, intraoperative minimum body temperature ≥35.5°C (IntMinBT ≥35.5°C), maximum heart rate during POD0-1 (MaxHR) for NLR; age and IntMinBT ≥ 35.5°C for LCR; and age and MaxHR for CAR. The threshold of "elderly" was determined as 102-year-old for NLR, 94-year-old for LCR, and 97-year-old for CAR.

Conclusions: The increased age causes the unfavorable changes in early postoperative immunoinflammatory indices after the uncomplicated laparoscopic cholecystectomy. Thus, the term "elderly" can be rephrased by the term "vulnerable to various surgical stresses." The thresholds for "elderly" defined herein seem impractical. Namely, the increased vulnerability caused by the aging seems modified by the individual surgical procedures.