Contamination of Blood Cultures Drawn From Arterial Catheters Versus Venipuncture or Venous Catheters in Critically Ill Patients: A Systematic Review and Meta-analysis.

BACKGROUND

Arterial catheter-drawn blood culture sampling may reduce patient discomfort and healthcare providers' workload. Guidelines discourage transcatheter blood culture collection due to contamination risks, mainly derived from data on venous catheter-drawn cultures. However, contamination rates of arterial catheter-drawn cultures have not been comprehensively evaluated compared with venipuncture- or venous catheter-drawn cultures.

METHODS

We searched PubMed, Embase, and the Cochrane Library from inception through 5 December 2023, for studies comparing arterial catheter-drawn blood cultures with venipuncture- or venous catheter-drawn blood cultures. The primary outcome was blood culture contamination rate. We performed a random-effects meta-analysis and evaluated the certainty of the evidence using the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) methodology.

RESULTS

We included 6 studies involving 8533 blood cultures. When comparing arterial catheter- with venipuncture-drawn cultures, the crude contamination rates were 28/1355 (2.1%) and 103/4539 (2.3%), respectively. Arterial catheter-drawn cultures may not increase contamination rates compared to venipuncture-drawn cultures (risk difference [RD], 0.01 [95% confidence interval {CI}, -.01 to .02]; low certainty). When comparing arterial catheter- with venous catheter-drawn cultures, the crude contamination rates were 15/489 (3.1%) and 211/2639 (8.0%), respectively. Compared to venous catheter-drawn cultures, arterial catheter-drawn cultures may have lower contamination rates (RD, -0.05 [95% CI, -.11 to .01]; low certainty).

CONCLUSIONS

In critically ill patients, arterial catheter-drawn blood cultures may have contamination rates comparable to venipuncture-drawn cultures and potentially lower than venous catheter-drawn cultures.

CLINICAL TRIALS REGISTRATION: PROSPERO (CRD42023486227).