PRE-OPERATIVE EGFR AND LENGTH OF POST-OPERATIVE HOSPITALISATION IN TUMOUR NEPHRECTOMY PATIENTS

S DEL VECCHIO¹, E ROBERT¹, L NG KENG^2,3, G GOBE^1,4, S WOOD²

¹Kidney Disease Research Group, University of Queensland, Brisbane, Australia; ²Department of Urology, Princess Alexandra Hospital, Brisbane, Australia; ³Department of Surgery, University Malaya, Kuala Lumpur, Malaysia; ⁴NHMRC Centre for Research Excellence on CKD.QLD, University of Queensland, Brisbane, Australia

Aim: To identify the relationship between pre-operative eGFR and length of hospital stay (LOHS) in patients undergoing tumour nephrectomy surgery.

Background: Patients with impaired kidney function are at increased risk of developing kidney tumours, especially renal cell carcinoma (RCC). As eGFR decreases, metabolic changes occur within the kidney that promote neoplastic processes. These patients also generally have a significant comorbidity burden. This study aimed to evaluate duration of hospitalisation following nephrectomy compared by pre-operative eGFR.

Methods: All patients undergoing nephrectomy for renal tumours at the Princess Alexandra Hospital (QLD) were consented and enrolled; sample size was 221. Patients were grouped by pre-operative eGFR. Patients in group 1 (n=12) had an eGFR <30; group 2 (n=36) had an eGFR of 30-60, and group 3 (n=173) had an eGFR of >60 ml/min/1.73m². The primary outcome was LOHS following surgery (assessed using Kruskal Wallis ANOVA with multiple comparisons).

Results: The median (IQR) post-operative LOHS in days was 6 days (4-7) for group 1, 4 days (3-7) for group 2, and 4 days (3-5) for group 3. Between groups, worsening eGFR was shown to be significantly associated with longer LOHS (p= 0.004). Both group 1 and 2 were significantly different from group 3 (p=0.045 and 0.034, respectively); difference between group 1 and 2 did not reach statistical significance.

Conclusions:  Patients with impaired kidney function have a significant disease burden which may contribute to prolonged duration of hospitalisation. Patients with lower pre-operative eGFR are likely to experience a significantly longer duration of hospitalisation following nephrectomy surgery compared to patients with patients with higher pre-operative eGFR.