This study aimed to investigate the effects of repeated preoperative intranasal administration
of insulin on the incidence of postoperative delirium (POD) and the levels of serum
proinflammatory markers in elderly patients undergoing laparoscopic radical gastrointestinal
Prospective, randomized, double-blinded, placebo-controlled clinical study.
General Hospital of Western Theater Command from August 2019 to December 2019.
Ninety elderly patients underwent laparoscopic radical gastrointestinal tumor resections
under general anesthesia.
Patients were randomly divided into a control group (0.5 mL saline administered intranasally)
or an insulin group (20 U/0.5 mL insulin administered intranasally) for 2 days prior
to surgery, with 45 patients in each group.
The incidence of delirium was measured at postoperative day 1 (T2), day 3 (T3), and
day 5 (T4) using the Confusion Assessment Method for the intensive care unit (CAM-ICU).
Plasma levels of interleukin (IL)-1β, IL-6, and tumor necrosis factor (TNF)-α were
measured at T0 (before insulin or saline administration), T1 (at the end of surgery),
T2, T3, and T4 by enzyme-linked immunosorbent assay.
Compared with the control group, the insulin group demonstrated a decreased POD incidence
(12.5% vs. 47.5%, P = 0.001) within 5 days after surgery. The incidence of POD was
significantly lower in the Ins group than in the Con group at T2 (12.5% vs. 32.5%,
P = 0.032) and at T3 (2.5% vs. 20%, P = 0.034). The incidence of POD decreased in
both groups over time and was similar at T4 (0% vs 10%, P = 0.116). Compared with
the baseline value at T0, serum TNF-α, IL-6 and IL-1β concentrations increased significantly
at T1-4 (P < 0.05). Compared with the control group at the same time point, the expression
levels of TNF-α, IL-6 and IL-1β in group I at T2 and T3 were significantly reduced
(P < 0.05). The incidence rates of adverse events were similar in the two groups.
Repeated preoperative intranasal administration of insulin prevented the occurrence
of delirium after laparoscopic radical gastrointestinal surgery in elderly patients
and reduced TNF-α, IL-1β, and IL-6 levels.