Impact of surgical delays on pre-operative complications in primary GBM patients- a 5-year study
Authors: Nazar Thaaqib , Price Stephen 
Published: October 2021

Abstract

Aims
Glioblastoma Multiforme (GBM) is one of the most aggressive primary brain tumors with poor prognosis (median survival 18 months) and no cure. Management strategies often involve maximum safe resection followed by chemoradiotherapy. There has been a move from managing such patients electively rather than the traditional model of treating them as an emergency. While this may have advantages, this can delay the time from presentation to operation. This delay has recently been further compounded by the current COVID-19 pandemic.
There is no data available as to whether the surgical delays that are currently occurring have an impact on patient care, and may outweigh the benefits of elective management on health services.
We aimed to conduct a single centre observational study to assess how long patients should be waiting prior to surgery. We hypothesised that the longer the wait, the higher the pre-operative complication rate and worse the outcomes.

Method
698 patients in a GBM database over a 5-year period (29/10/14- 8/11/19) were studied. All patient data was accessed via electronic patient records
Surgical delay was defined as the interval between date of being put on the waiting list (the date seen in the neuro-oncology clinic) to date of surgery.
Primary outcome measure was preoperative complications, which was categorised into transient neurological decline, stroke, seizures, diabetes/erratic blood sugars, emergency admission, others (e.g., cardiovascular compromise, steroid complications, blood disorders)
Inclusion criteria included: First presentation supratentorial WHO Grade 4 GBM confirmed on histology (this included histological variants such as Gliosarcoma and Epithelioid Glioblastoma), and all patients who had been seen in the neuro-oncology clinic prior to surgery.
Exclusion criteria included all patients who were not thought to have a GBM or high-grade glioma on initial imaging, those admitted as an emergency without being seen in a neuro-oncology clinic, recurrent or secondary GBMs.

Results
460 patients met the inclusion criteria in this study. There was a pre-operative complication rate of 14.6% (67/460). 55% of complications were due to a transient neurological decline (37/67) with 16.4 % (11/67) of patients presenting with seizures. For those with surgical delays ≤7 days pre-operative complication rates were 2.2 % vs 15.9% in those with delays &gt;7 days, p value 0.012, Odds ratio 8.53 (95% CI 1.48- 88.09). Results were statistically significant in those with delays greater than 10 and 14 days (p values 0.0026 and 0.0004 respectively)
ROC Curve analysis revealed an AUC of 0.66 with sensitivities of 99%, 90% and 76% at surgical delays of 7,10 and 14 days respectively.
The median length of hospital admission in both groups of patients was 5 days (p= 0.2065)
All statistical analysis was carried out using Prism 9 and SPSS

Conclusion
In spite of unchanged length of hospital stay, we note a significant increase in pre-operative complication rates as a result of surgical delays greater than 7,10 and 14 days, which introduces an interesting debate in the merit of delaying operations for further assessment in clinic. Our objectives would be to minimize complication rate, therefore a high sensitivity i.e. true positive rate would be most desirable. The 99% levels achieved at 7 days In the ROC analysis lends weight to introducing policy to fast-track admissions for primary GBM patients.
Further directions could include assessing the impact reduced surgical services and redeployment might have had on complications rates and length of hospital stay on patients admitted over the COVID 19 pandemic.