Changes of cerebral oxygenation saturation and postoperative cognitive function in anemia patients undergoing laparoscopic surgery

  Background  Brain is sensitive to hypoxic injury, and anemia can cause decreased cerebral oxygen concentration in patients during operation. However, few studies have explored the effect of anemia on central nervous system during perioperative period.

  Objective  To explore the effect of different degree of anemia on intraoperative cerebral oxygenation saturation and postoperative cognitive function in patients undergoing laparoscopic surgery.

  Methods  Totally 132 patients undergoing elective laparoscopic surgery from October 2018 to October 2019 were divided into normal group (group N, n=58), mild anemia group (group A, n=45) and moderate anemia group (group B, n=29) according to preoperative hemoglobin concentration. MAP, HR, SPO₂ and etCO₂ were recorded at the beginning of the operation (T₁), body position change (T₂), 40 min after body position change (T₃) and the end of artificial pneumoperitoneum (T₄), and the average cerebral oxygen saturation (rSO₂) of each period and incidence of cerebral hypoxia were calculated. Changes of serum S100β between before and after surgery as well as the incidence of postoperative cognitive dysfunction (POCD) were compared among groups.

  Results  There was no significant difference in general condition, preoperative serum S-100β concentration, preoperative MoCA score at each time point among different groups (P > 0.05). No significant difference was found in rSO₂, incidence of cerebral hypoxia and recovery time between the group N and the group A, while rSO₂ at T₀ (63.6%±8.5% vs 70.7%±6.3%) and T_3-4 (71.6%±17.8% vs 81.2%±7.5%) in the group A were significantly lower than those in the group N, and the incidence of cerebral hypoxia (34.5% vs 10.4%), recovery time (17.4 ± 4.9 min vs 14.0±4.7 min) were significantly higher than those in the group N (P < 0.05, respectively). Compared with group N, MoCA score (286 vs 279, P=0.03) were significantly lower, and serum S-100β concentration (0.48±0.17 μg/L vs 1.08±0.37 ug/L, P<0.01) and the incidence of POCD (17.2% vs 44.8%, P=0.02) were significantly higher after surgery in the group B (P < 0.05).

  Conclusion  Patients with moderate anemia are more prone to have cerebral oxygen desaturation and central nerve injury during laparoscopic surgery, those may lead to a higher incidence of POCD.