Assessment of Aseptic Technique Adherence and Turnaround Time in Blood Culture Collection: A Descriptive Study

Background

Blood culture contamination(BCC) impacts antimicrobial therapy decisions for patients with suspected bacteremia. At Kijabe Hospital(KH), contamination rates persist at 14.7% on average, above the CLSI-recommended ≤3%, despite phlebotomy team training. This study aimed to assess phlebotomy blood collection practices and track turnaround time(TAT).

Methods

A blinded observational study targeting phlebotomists was conducted across multiple hospital wards for three months. Observations were performed by select trained phlebotomists and patient assistants who completed a structured data collection tool designed on RedCap. TAT was determined by recording the time of collection during observation and the time of laboratory reception and processing, as documented in the Hospital EMR. Data analysis was performed using STATA statistical software. Chi-square tests were used to analyze associations between aseptic technique adherence and sample outcomes. ANOVA tests evaluated relationships between TAT and culture results.

Results

78 sample collection observations were completed. Majority of blood collections (92.3%, n=72) were performed by phlebotomists. Correct blood volume collection was achieved in 97.4% (n=76) of observations. Critical gaps were identified in hand hygiene practices, with 33.3% (n=26) performing adequate hand hygiene(HH) before blood collection. Full aseptic technique(FAT) was observed in 73.1% (n=57) of collections, while aseptic technique was maintained throughout the entire collection process in 85.9% (n=67) of cases.
Proper HH was significantly associated with reduced contamination (χ²=8.724, p=0.013), with contamination rates of 19.2% (10/52) when HH was inadequate compared to 3.8% (1/26) when proper hand hygiene was performed. FAT showed a strong association with sample outcomes (χ²=18.961, p<0.001). Collections without FAT had contamination rates of 42.9% (9/21) compared to 3.5% (2/57) with FAT.
The mean time from symptom onset to sample collection was 21.83 hours (SD=18.85). Collection to laboratory reception showed a mean turnaround time of 8.16 hours (SD=12.93). ANOVA testing revealed that contaminated cultures had significantly longer collection-to-laboratory turnaround times (mean=14.27 hours) compared to samples yielding pathogens (mean=4.38 hours; F=3.86, p=0.026). Nine samples (11.5%) had multiple orders placed at 30-minute intervals, suggesting workflow or communication issues between clinical and laboratory teams.
Of the 78 processed samples, 12.8% (n=10) yielded clinically significant pathogens, 14.1% (n=11) grew SOSAs, and 73.1% (n=57) demonstrated no bacterial growth. 

Discussion

The substantial time delays between collection and laboratory reception (mean 8.16 hours) indicate significant inefficiencies in the specimen management workflow. These delays, coupled with documentation inconsistencies arising from dual paper-based and online systems, likely contribute to communication challenges hence late collection. Statistical analysis confirms that longer transport times significantly correlate with higher contamination rates (p=0.026). The low HH compliance (33.3%) represents a critical gap in aseptic technique despite otherwise good adherence to collection protocols, with HH being significantly associated with culture outcomes (p=0.013). The failure to maintain aseptic technique throughout collection resulted in dramatically higher contamination rates (63.6% vs 6.0%, p<0.001), highlighting the importance of consistent application of IPC. Multiple sample orders within short time frames suggest communication or documentation challenges between clinical and laboratory teams, exacerbated by fragmented documentation systems.

Conclusion

Despite dedicated phlebotomy teams, significant deficiencies persist in hand hygiene practices and consistent application of aseptic techniques during blood culture collection. Statistical analysis confirms that these procedural lapses, along with substantial delays in specimen transport, directly contribute to the high contamination rates and low yield. Targeted interventions focusing on hand hygiene compliance, strict adherence to aseptic technique throughout the collection process, streamlined transportation logistics, and improved documentation practices are recommended to reduce contamination rates and improve the diagnostic yield of blood cultures.

Keywords

Blood culture contamination, phlebotomy practices, aseptic technique, turnaround time, diagnostic yield