Laboratory and clinical impacts of an overnight laboratory service.

Delayed initiation of effective antimicrobial therapy for sepsis is associated with increased mortality. Whilst automated blood culture machines operate continuously, this does not align with conventional staff working hours and so turn-around-times (TAT) for reporting gram stains to clinicians are 3-7 times longer for blood cultures that flag positive overnight. We retrospectively compared laboratory TATs and clinical outcomes for blood cultures from 183 patients that flagged positive overnight during a 4-month period before and after the implementation of an overnight laboratory service. Enterobacterales and urinary tract infections were the most frequent pathogens and clinical syndrome respectively, and the prevalence of multi-resistant organisms was 15%. Compared with the pre-implementation period, the post-implementation period was associated with shorter median time from blood culture positivity to gram stain (7.4 vs 1.2 h), first genus level identification (7.2 vs 5.8 h) and first antimicrobial susceptibility result (24.1 vs 7.9 h). Similarly, the median time from blood culture positivity to clinicians first being informed was significantly shorter (9.2 vs 1.3 h). After removal of likely contaminants, 78% of patients were on effective empiric antimicrobials and for patients on ineffective empiric antimicrobials, effective therapy was initiated a median of 3.2 h sooner during the post-implementation period, without impact on mortality. Implementation of an overnight laboratory service was associated with significantly faster TAT for reporting blood culture results and more prompt initiation of effective antimicrobials for patients receiving ineffective empiric therapy, improving attainment of sepsis management goals.

Intra-assay reliability and robustness of QuantiFERON(R)-TB Gold In-Tube test in Zambia.

BACKGROUND: Interferon-gamma (IFN-gamma) release assays (IGRAs), such as the QuantiFERON-TB Gold In-Tube test (QFT-GIT), are becoming a preferred method for diagnosis of tuberculosis (TB) infection in many industrialised countries. However, data on the effectiveness of IGRAs in high TB-HIV (human immunodeficiency virus) endemic and resource-limited settings, such as Zambia, are limited. OBJECTIVE: To determine the intra-assay reliability and robustness of QFT-GIT in a field setting in Zambia. DESIGN: During July-October 2007, 109 adult smear-positive TB patients were recruited to determine QFT-GIT reliability and the effect of a 24-h delay in incubation. Two simulated laboratory experiments were also performed using 9-14 volunteers, to explore the effect of power outages during incubation and storage temperature of collection tubes on IFN-gamma responses. RESULTS: QFT-GIT intra-assay concordance was 91.7% (kappa = 0.8). Discordance was observed for nine patients, of whom six were HIV-positive. There was evidence of an association between HIV status and discordant results (OR 1.98, 95%CI 1.06-3.67, P = 0.03). A 24-h delay in incubation changed results for 25 of the 109 (22.9%) patients. Power outages that altered incubation time reduced IFN-gamma responses. CONCLUSION: Although QFT-GIT seems reliable in this setting, we have identified operational factors that affect its robustness. These factors may influence the effectiveness of this test in similar resource-limited settings.

Improvement in time to treatment following establishment of a dedicated medical admissions unit.

The importance of medical admissions units (MAU) has been emphasised by the royal colleges and the Society for Acute Medicine. This study looked at the time to treatment of four common medical conditions before and after the establishment of a dedicated MAU. Before the development of the MAU, treatment given in the emergency department (ED; median 111 minutes) was significantly quicker than on the admitting general medical ward (median 262 minutes, p<0.001). Following the establishment of the MAU, treatment given in the ED (median 70 minutes) remained significantly quicker than on the MAU (median 180 minutes, p<0.05). Treatment was given significantly quicker on the MAU compared with the antecedent admitting medical wards (p<0.05). In addition, more patients were treated within protocol-driven time guidelines. In summary, the establishment of a MAU significantly improved time to treatment, compared with admitting directly to general medical wards. This has implications for patients who are boarded directly to medical wards when the MAU is at full capacity.

Bridging the Quantum gap: attaining adequacy utilizing the Quantum night-time exchange device.

BACKGROUND: The advent of night-time exchange devices (NXDs), such as the Quantum, gives the client on home peritoneal dialysis the option of five exchanges well spaced in a day or, for those who need only four exchanges a day, the ability to change their long dwell to the daytime. PURPOSE: To ascertain whether we were able to attain the NKF-DOQI recommended Kt/V of 2.0 for CAPD clients by adding a fifth exchange utilizing the Quantum NXD or by introducing a long daytime dwell for clients who only needed four exchanges per day. We also looked at alternative uses for a NXD. METHOD: As part of our CQI process for all clients on home peritoneal dialysis, dialysis adequacy testing is performed two weeks after the start of full prescription and biannually thereafter. In this study, the first group of clients, the "lifestyle group", changed to using the NXD to allow more daytime freedom. This first group had repeated 24 hour dialysate collections to ensure they maintained adequate Kt/Vs. The second group of clients, the "adequacy group", had Kt/Vs falling below the NKF-DOQI recommendation of 2.0. This second group had their peritoneal dialysis prescription optimized utilizing a computer modeling program. Their prescription was then changed accordingly Two weeks after the change in prescription, 24 hour dialysate collections were repeated for each client to ensure the new Kt/Vs were within the predicted parameters. CONCLUSIONS: We were able to attain the NKF-DOQI recommended Kt/V, utilizing the CANUSA recommended fill volumes, for all clients underdialyzed on CAPD through the addition of a fifth exchange using the NXD. Other clients who may benefit from the use of NXDs are those who need more daytime freedom.