Abrahams Mohammad Shareef, Whitelaw Andrew C, Orth Heidi
Division of Medical Microbiology, Faculty of Health Sciences, National Health Laboratory Service and Stellenbosch University, Tygerberg, Cape Town, South Africa.
S Afr Med J. 2015 Nov 6;105(12):1039-43. doi: 10.7196/SAMJ.2015.v105i12.9442.
The benchmark for contaminated blood cultures (BCs) is 3%. The South African (SA) guideline aims to optimise BC yield and reduce contamination. Data on BC collection practices in SA since the publication of the 2010 SA guideline are lacking.
To evaluate compliance with the national guideline for the optimal use of BCs and determine the BC contamination rate at a local district hospital.
An audit of compliance with 22 BC standards was conducted at a district hospital in Cape Town, SA. Standards were evaluated by reviewing clinical and laboratory data and by a clinician questionnaire.
Of the 425 BCs reviewed, 12.5% had positive growth, and 4.5% grew contaminants. Only 33% of BC bottles contained the recommended fill volume of 8-10 mL, and 96.9% of patients had a single BC within a 24-hour period. Of all the BCs, only 7.8% had a combined blood volume of at least 20 mL. The yield of pathogens in BCs collected after antibiotic exposure was 4.9% compared with 7.5% for those cultures with no prior antibiotic exposure (p=0.3). The overall median needle-to-incubator transport time was 11 hours 25 minutes.
The BC contamination rate was high and compliance with most standards was variable or not met. The findings may not be generalisable to other hospitals, and we recommend that each institution reviews its own BC practices. Recommendations made to hospital staff included a re-audit following implementation of these recommendations.
污染血培养（BC）的基准率为3%。南非（SA）指南旨在优化血培养产量并减少污染。自2010年南非指南发布以来，缺乏关于南非血培养采集实践的数据。
评估对国家血培养最佳使用指南的依从性，并确定当地一家区级医院的血培养污染率。
在南非开普敦的一家区级医院对22项血培养标准的依从性进行了审核。通过审查临床和实验室数据以及临床医生问卷调查来评估标准。
在审查的425份血培养中，12.5%有阳性生长，4.5%培养出污染物。只有33%的血培养瓶含有推荐的8 - 10 mL填充量，96.9%的患者在24小时内进行了单次血培养。在所有血培养中，只有7.8%的总血容量至少为20 mL。抗生素暴露后采集的血培养中病原体的检出率为4.9%，而未预先暴露于抗生素的培养物的检出率为7.5%（p = 0.3）。从采血到放入培养箱的总体中位运输时间为11小时25分钟。
血培养污染率高，对大多数标准的依从性参差不齐或未达到要求。这些发现可能不适用于其他医院，我们建议每个机构审查自己的血培养实践。向医院工作人员提出的建议包括在实施这些建议后进行重新审核。
