Plasma Concentration of the Lipid Peroxidation (LP) Biomarker 4-Ηydroxynonenal (4-HNE) in Benign and Cancer Patients

Background/aim: The present study investigated the plasma concentration of the lipid peroxidation (LP) biomarker 4-hydroxynonenal (4-HNE) in benign and cancer patients having the rectus sheath block (RSB) analgesia after midline laparotomy. Plasma concentrations of catalase (CAT) and malondialdehyde (MDA) were used as a reference.

Patients and methods: This study assessed three LP biomarkers; CAT, MDA and 4-HNE and compared the plasma levels to the patient satisfaction 24 h postoperatively (SFS₂₄; 0=fully unsatisfied; 10=fully satisfied); the overall pain at rest (NRS_r) and when pressing the wound at 20 Newton force (NRS_p) were surveyed and filed on a 11-point numeric rating scale at 24 h following surgery (NRS; 0=no pain; 10=worst pain). There were 56 patients in the study, of whom 12 were excluded due to missing plasma samples. The final study cohort consisted of 15 patients with benign disease and 29 patients with cancer.

Results: The RSB analgesia enhanced significantly the SFS₂₄ scores in the study groups (p=0.001). The plasma 4-HNE decreased immediately after operation (POP1) and the postoperative decrease between the preoperative and the POP1 values in the 4-HNE marker were statistically significant (p<0.001). The individual plasma 4-HNE and MDA concentration correlated significantly in benign and cancer patients (r=0.413, p<0.001).

Conclusion: The present study confirms the applicability of the plasma biomarker 4-HNE to cast further light on the postoperative pain in midline laparotomy patients.