Routine Versus Clinically Indicated Cerebrospinal Fluid Sampling During Diversion Procedures: A Second-Cycle Audit at a Tertiary Neurosurgical Centre in the United Kingdom
Year: 2026
Type: article
Study design: Observational Study
Abstract: Background Cerebrospinal fluid (CSF) cultures contribute to the investigation of suspected infection associated with CSF diversion procedures. However, routine intraoperative sampling in patients without suspected infection may yield organisms, often skin commensals, of uncertain or insignificant clinical significance. A first-cycle local audit of 172 samples found that most cultures were negative and few led to treatment, and recommended avoiding routine sampling in elective cases where infection was not suspected. The primary objective of this second-cycle audit was to determine whether routine CSF sampling (performed when infection was not suspected) led to culture-driven changes in management, compared with clinically indicated sampling (performed when infection was suspected). Secondary objectives were to compare culture positivity and antibiotic initiation between the two groups and to assess the consistency of documentation of the sampling indication. Methods A retrospective re-audit of all intraoperative CSF specimens from shunt and external ventricular drain procedures at a tertiary neurosurgical centre in the United Kingdom was undertaken (from August 2024 to July 2025). Specimens were classified as routine or clinically indicated using pre-specified criteria applied to operative notes, electronic records, and microbiology request forms. The author classified all specimens and extracted all outcomes; there was no independent second reviewer. The primary outcome was a documented change in management attributable to the culture result. Categorical data were summarised as counts and percentages. No formal statistical testing was undertaken, consistent with the descriptive nature of this audit. Results Of 78 specimens, 60 (76.9%) were routine, and 18 (23.1%) were clinically indicated. Culture positivity was 16.7% (10/60) for routine and 44.4% (8/18) for clinically indicated specimens. None of the 10 routine positive cultures led to a change in management (0/10 positive routine specimens), whereas 7 of 8 indicated positive cultures did (87.5%). Microbiology request wording and clinical documentation were discordant on the indication in 14 specimens (17.9%). Conclusion Routine intraoperative CSF sampling persisted despite first-cycle guidance and, in this cohort, did not change documented management, whereas clinically indicated sampling accounted for all culture-driven management changes. The small number of events limits precision, and the absence of documented harm in a retrospective audit cannot establish that omitting routine sampling is safe. Therefore, a prospective evaluation of an indication-based pathway, with structured documentation of the indication and the missed-infection rate as a balancing measure, is warranted.
Source: Cureus
Author: Yashjeet Basu
Institution: Royal Victoria Infirmary
Language: English
Subfield: General Health Professions
Field: Health Professions
Domain: Health Sciences
Open Access status: diamond
OpenAlex ID: W7225406332