BACKGROUND: 

The perioperative inflammatory response may be implicated in adverse outcomes including neurocognitive dysfunction and cancer recurrence after oncological surgery. The immunomodulatory role of anesthetic agents has been demonstrated in vitro; however, its clinical relevance is unclear. The purpose of this meta-analysis was to compare propofol and sevoflurane with respect to biomarkers of perioperative inflammation. The secondary aim was to correlate markers of inflammation with clinical measures of perioperative cognition.

METHODS: 

Databases were searched for randomized controlled trials examining perioperative inflammation after general anesthesia using propofol compared to sevoflurane. Inflammatory biomarkers investigated were interleukin (IL)-6, IL-10, tissue necrosis factor alpha (TNF-α), and C-reactive protein (CRP). The secondary outcome was incidence of perioperative neurocognitive disorders. Meta-analysis with metaregression was performed to determine the difference between propofol and sevoflurane.

RESULTS: 

Twenty-three studies were included with 1611 participants. Studies varied by surgery type, duration, and participant age. There was an increase in the mean inflammatory biomarker levels following surgery, with meta-analysis revealing no difference in effect between propofol and sevoflurane. Heterogeneity between studies was high, with surgery type, duration, and patient age contributing to the variance across studies. Only 5 studies examined postoperative cognitive outcomes; thus, a meta-analysis could not be performed. Nonetheless, of these 5 studies, 4 reported a reduced incidence of cognitive decline associated with propofol use.

CONCLUSIONS: 

Surgery induces an inflammatory response; however, the inflammatory response did not differ as a function of anesthetic technique. This absence of an effect suggests that patient and surgical variables may have a far more significant impact on the postoperative inflammatory responses than anesthetic technique. The majority of studies assessing perioperative cognition in older patients reported a benefit associated with the use of propofol; however, larger trials using homogenous outcomes are needed to demonstrate such an effect.