Introduction: Postoperative ischemia is a frequent phenomenon in patients with brain tumors and is associated with postoperative neurological deficits and impaired overall survival. Previous clinical and experimental studies have shown that the application of a brief ischemic stimulus not only in the target organ but also in a remote tissue can prevent ischemia. We hypothesized that remote ischemic preconditioning (rIPC) in patients with brain tumors undergoing elective surgical resection reduces the incidence of postoperative ischemic tissue damage and its consequences.
Methods: Sixty patients were randomly assigned to two groups, with 1:1 allocation, stratified after tumor type (glioma or metastasis) and previous treatment with radiotherapy. Remote ischemic preconditioning was induced by inflating a blood pressure cuff placed on the upper arm three times for 5 minutes at 200 mmHg in the treatment group after induction of anesthesia. Between the cycles, the blood pressure cuff was released to allow reperfusion. In the control group no preconditioning was performed. Early postoperative MR images were evaluated blinded to randomization for the presence of ischemia and its volume.
Results: Fifty-eight of the 60 patients were assessed for occurrence of postoperative ischemia. Of these 58 patients, 44 (75.9%) had new postoperative ischemic lesions. The incidence of new postoperative ischemic lesions was significantly higher in the control group (87.1%) (27/31) than in the rIPC group (63.0%) (17/27) (p=0.03). The median infarct volume was 0.36 cm3 (IR: 0.0- 2.35) in the rIPC group compared with 1.30 cm3 (IR: 0.29- 3.66) in the control group (p=0.09).
Conclusions: Application of rIPC significantly reduced the incidence of postoperative ischemic tissue damage in patients undergoing elective brain tumor surgery. This is the first study indicating a benefit of rIPC in brain tumor surgery.
Patient Care: Clinical application of rIPC in patients with brain tumors may provide benefits regarding prognosis and quality of life through reducing the incidence of postoperative ischemic events.
Learning Objectives: By the conclusion of this session, participants should be able to:
1) Understand the importance of ischemic preconditioning in the surgical treatment of brain tumors;
2) Discuss the prognostic relevance of postoperative ischemic events in patients with brain tumors;
3) Discuss future strategies for reducing the incidence of postoperative ischemic changes in these patients.