Pneumatic Tube Delivery System for Blood Samples Reduces Turnaround Times Without Affecting Sample Quality

Comparison of a two-step Tempus600 hub solution single-tube vs. container-based, one-step pneumatic transport system

OBJECTIVES

Efficient and timely transportation of clinical samples is pivotal to ensure accurate diagnoses and effective patient care. During the transportation process, preservation of sample integrity is crucial to avoid pre-analytical aberrations on laboratory results. Here, we present a comparative analysis between a two-step Tempus600 hub solution single-tube and a one-step, container-based pneumatic transport system (PTS) from Airco, for the in-house transportation of blood samples.

METHODS

Ten blood samples from healthy volunteers were split in 10 mL collection tubes filled at full or half capacity for transportation with the two PTS (about 250 m). To compare the impact of transportation, markers of hemolysis such as lactate dehydrogenase (LDH), potassium (K+), and the hemolysis index (HI), were determined. Additionally, differences in HI in routine samples and repeated transportation was investigated. To assess and compare the mechanistic impact profiles, we recorded the acceleration profiles of the two PTS using a shock data logger.

RESULTS

Transportation using the Tempus600 hub solution resulted in 49 and 46 % higher HI with samples filled to total or half capacity, respectively. Routine samples transported with the Tempus600 hub solution showed a higher median HI by 23 and 33 %. Additionally, shock logger analysis showed an elevated amount of shocks (6.5 fold) and shock intensities (1.8 fold).

CONCLUSIONS

The Tempus600 hub solution caused an increased number of unreportable LDH or K+ results based on the hemolysis index. However, it was only statistically significant for LDH (p<0.01 and p<0.08) - while the comparisons for K+ were not statistically significant (p<0.28 and p<0.56).

Comparison of the speed and quality of innovative and traditional pneumatic tube system transport outside of an emergency laboratory

Background

Ensuring the rapidity and accuracy of emergency laboratory test results is especially important to save the lives of patients with acute and critical conditions. To better meet the needs of clinicians and patients, detection efficiency can be improved by reducing extra-laboratory sample turnaround times (TATs) through the use of innovative pneumatic tube system (PTS) transport for sample transport. However, concerns remain regarding the potential compromise of sample quality during PTS transit relative to that occurring with manual transportation. This study was performed to evaluate the efficacy of an innovative PTS (Tempus600 PTS) relative to a traditional PTS in terms of sample transit time, sample quality, and the concordance of analytical results with those obtained from manually transported samples.

Methods

In total, 30 healthy volunteers aged >18 years were recruited for this study, conducted for five consecutive days. Venous blood samples were collected from six volunteers per day at fixed timepoints. From each volunteer, nine blood samples were collected into tubes with tripotassium ethylene diamine tetraacetic acid anticoagulant, tubes with 3.2 % sodium citrate, and serum tubes with separation gel (n = 3 each) and subjected to all tests conducted in the emergency laboratory in our hospital. 270 blood samples from 30 healthy volunteers were transported and analyzed, yielding 6300 test results. The blood samples were divided randomly into three groups (each containing one tube of each type) and transported to the emergency laboratory manually and with Tempus600 PTS and conventional Swisslog PTS, respectively. The extra-laboratory TATs, sample quality, and test results of the transported blood samples were compared.

Results

The sample quality and test results did not differ according to the delivery method. The TAT was much shorter with the Tempus600 than with the other two transport modes (58.40 ± 1.52 s vs. 1711.20 ± 77.56 s for manual delivery and 146.60 ± 1.82 s for the Swisslog PTS; P = 0.002).

Conclusion

Blood sample transport with the Tempus600 PTS significantly reduced the extra-laboratory TAT without compromising sample quality or test result accuracy, thereby improving the efficiency of sample analysis and the services provided to clinicians and patients.

Diagnostic sample transport via pneumatic tube systems: data logger and their algorithms are sensitive to transport effects

OBJECTIVES

Many hospitals use pneumatic tube systems (PTS) for transport of diagnostic samples. Continuous monitoring of PTS and evaluation prior to clinical use is recommended. Data loggers with specifically developed algorithms have been suggested as an additional tool in PTS evaluation. We compared two different data loggers.

METHODS

Transport types - courier, conventional (cPTS) and innovative PTS (iPTS) - were monitored using two data loggers (MSR145® logger, CiK Solutions GmbH, Karlsruhe, Germany, and a prototype developed at the University Medicine Greifswald). Data loggers differ in algorithm, recording frequencies and limit of acceleration detection. Samples from apparently healthy volunteers were split among the transport types and results for 37 laboratory measurands were compared.

RESULTS

For each logger specific arbitrary units were calculated. Area-under-the-curve (AUC)-values (MSR145®) were lowest for courier and highest for iPTS and increased with increasing recording frequencies. Stress (St)-values (prototype logger) were obtained in kmsu (1,000*mechanical stress unit) and were highest for iPTS as well. Statistical differences between laboratory measurement results of transport types were observed for three measurands sensitive for hemolysis.

CONCLUSIONS

The statistical, but not clinical, differences in the results for hemolysis sensitive measurands may be regarded as an early sign of preanalytical impairment. Both data loggers record this important interval of beginning mechanical stress with a high resolution indicating their potential to facilitate early detection of preanalytical impairment. Further studies should identify suitable recording frequencies. Currently, evaluation and monitoring of diagnostic sample transport should not only rely on data loggers but also include diagnostic samples.

Influence of pneumatic tube delivery system on laboratory results

INTRODUCTION

The pneumatic tube system (PTS) is an automated and fast modality of transportation of biological samples, but it has been reported to induce preanalytical errors.

AIM

To study the influence of transportation by PTS on biochemistry tests which are particularly sensitive to haemolysis and atmospheric pressure variation.

MATERIALS AND METHODS

We compared laboratory results of arterial blood gas, sodium, potassium, chloride, lactate dehydrogenase, aspartate aminotransferase, alanine aminotransferase, glucose and haemolysis index of samples conveyed simultaneously by PTS and by courier.

RESULTS

We recruited 30 patients from the sampling room and 40 patients from the intensive care unit. Transport through PTS resulted in a significant increase in aspartate aminotransferase and potassium without exceeding the limits of acceptability. Potassium was significantly more increased for samples transported in a higher speed line (p = .048) but without exceeding the limits of acceptability. No significant impact was noted on haemolysis indices. The pO2 variations due to PTS transportation exceeded the limit of acceptability with significant intra-individual variations.

CONCLUSION

Our PTS is validated for biochemistry tests results. It reduces turnaround times without affecting sample quality. However, the interpretation of arterial blood gas results should be careful for samples transported by PTS.

Monitoring and Root Cause Analysis of Clinical Biochemistry Turnaround Time at a Tertiary Care Institute

INTRODUCTION

Most laboratories around the world have focused on improving the analytical quality of laboratory tests. Laboratory turnaround time (TAT) is often left unnoticed and under-recognised in the healthcare setting. Both patients and clinicians are more interested in receiving rapid, reliable, and accurate results. This can be achieved by improving the TAT through the identification of the causes that lead to delayed TAT.

MATERIALS AND METHODS

This prospective study aims to identify the cause of delayed TATs within the outpatient department and implement corrective strategies to overcome them. A total of 214 samples were received. The study was conducted for a period of two years; of all the samples received, 154 were from the outpatient department, and 78 samples exceeded the expected TAT. The samples were analysed in the clinical biochemistry department of the hospital. The time spent at each station was determined using an internal computer system, which was also used to identify the samples that exceeded TATs. The primary outcome of the study was to identify the number of samples exceeding TAT and the causes of it.

RESULTS

Upon implementation of corrective measures and root cause analysis, the TATs were reduced from 80-88% to 11-33%. After analysing the duration of time for the samples that exceeded TAT, 45.1% and 37.5% exceeded 30 minutes in Year 1 and Year 2, respectively. Only 3.2% and 6.2% exceeded five hours in Year 1 and Year 2, respectively. Furthermore, using root cause analysis, it was found that 12% of the delay was due to increased waiting time or sample collection, 14% included other causes such as outsourcing of samples, and 18% of the delay was due to pre-analytic processing time.

CONCLUSION

Our study concludes that TAT is an important quality assessment tool within the laboratory setting, and with proper identification of causes, it can be improved. Although monitoring TAT is a tedious process that mandates tremendous efforts, with the presence of real-time monitoring, improving TAT is an achievable goal. This, in turn, can improve patient treatment outcomes and clinician satisfaction.

Impact of Pneumatic Transport System on Preanalytical Phase Affecting Clinical Biochemistry Results

Introduction PTS (pneumatic transport system) is extensively being used in modern hospitals for rapid transportation of blood samples and other specimens. However, it has a potential impact on blood components, which should be investigated and nullified accordingly. This study was part of a correction program aimed at reducing hemolysis. It was done by comparing paired samples transported manually and by PTS.

Materials and Methods This study was initiated to monitor the impact of PTS on hemolysis of clinical biochemistry blood samples. It was performed in two phases—before and after the corrective action taken. Phase I: done after PTS installation but before the corrective action was taken. Duplicate samples from 100 healthy individuals were collected, one set transported by PTS and the other by human carriers. Both sets were assessed for 25 biochemistry analytes, hemolysis index (HI), and acceleration profiles using a data logger. Corrective measures were then taken, followed by phase II of the study. In phase II, the sample size and study design remained the same as phase I. All the test results of PTS and hand-carried samples were statistically analyzed for any significant difference.

Result In phase I, all the hemolysis-manifesting parameters, LDH (lactate dehydrogenase), potassium, AST (aspartate transaminase), and phosphorus, were raised in PTS samples as compared with the manual samples. Their differences were significant as the p-values were 0.001, 0.000, 0.025, and 0.047, respectively. The differences for LDH and potassium were clinically significant as well. HI (9%) and peak acceleration (15.7 g) were high in PTS samples.

In phase II, no statistically significant difference between paired samples was found for all biochemistry parameters except for a few which were clinically nonsignificant. For PTS samples, HI was 2.5% and the peak acceleration was 11.2 g, whereas for manual samples, HI was 2%.

Conclusion Evidence of hemolysis was found in PTS samples as compared with handheld samples, which was resolved after several corrective actions were taken. Thereafter, PTS became reliable for sample delivery in a routine biochemistry laboratory. Hence, each hospital should scrutinize their PTS for its effects on sample integrity to get rid of PTS-induced preanalytical errors.

Investigation of the effects of pneumatic tube transport system on routine biochemistry, hematology, and coagulation tests in Ankara City Hospital

OBJECTIVES

Academics are far from a consensus regarding the effects of pneumatic tube system (PTS) delivery on sample integrity and laboratory test results. As for the reasons for conflicting opinions, each PTS is uniquely designed, sample tubes and patient characteristics differ among studies. This study aims to validate the PTS utilized in Ankara City Hospital for routine chemistry, coagulation, and hematology tests by comparing samples delivered via PTS and porter.

METHODS

The study comprises 50 healthy volunteers. Blood samples were drawn into three biochemistry, two coagulation, and two hemogram tubes from each participant. Each of the duplicate samples was transferred to the emergency laboratory via Swiss log PTS (aka PTS-immediately) or by a porter. The last of the biochemistry tubes were delivered via the PTS, upon completion of coagulation of the blood (aka PTS-after). The results of the analysis in these groups were compared with multiple statistical analyses.

RESULTS

The study did not reveal any correlation between the PTS and serum hemolysis index. There were statistically significant differences in several biochemistry tests. However, none of them reached the clinical significance threshold. Basophil and large unidentified cell (LUC) tests had poor correlations (r=0.47 and r=0.60; respectively) and reached clinical significance threshold (the average percentages of bias, 10.2%, and 15.4%, respectively). The remainder of the hematology and coagulation parameters did not reach clinical significance level either.

CONCLUSIONS

The modern PTS validated in this study is safe for sample transportation for routine chemistry, coagulation, and hematology tests frequently requested in healthy individuals except for basophil and LUC.

Effects of a pneumatic tube system on the hemolysis of blood samples: a PRISMA-compliant meta-analysis

Many studies have explored how using a pneumatic tube system (PTS) is related to the hemolysis of blood samples, but their conclusions have been inconsistent. This meta-analysis was to clarify whether using a PTS induces the hemolysis of blood samples. The PubMed, Embase, Scopus, CNKI, CqVip, SinoMed and WanFang databases were searched for studies published between January 1970 and August 2019. The primary outcomes were the hemolysis rate and hemolysis index of blood samples after applying a PTS and manual transportation. We estimated the pooled risk ratio (RR) and the standardized mean difference (SMD), using random-effects models. This meta-analysis included 29 studies covering 3121 blood samples. No significant differences were found between the PTS and manual-transportation groups in the hemolysis rate [RR: 0.99, 95% confidence interval (CI): 0.57 to 1.70], hemolysis index (SMD: 0.19, 95% CI: -0.00 to 0.38), or level of potassium (SMD: 0.05, 95% CI: -0.03 to 0.12), alanine aminotransferase (SMD: 0.00, 95% CI: -0.10 to 0.11), or aspartate aminotransferase (SMD: 0.04, 95% CI: -0.08 to 0.17). However, lactate dehydrogenase (LDH) level was significantly higher in the PTS group than in the manual-transportation group (SMD: 0.20, 95% CI: 0.06 to 0.34). Subgroup analysis revealed that the LDH level was clearly higher in the PTS group than in the manual-transportation group only when the PTS speed was ≥6 m/s or when the PTS distance was ≥250 m. According to this meta-analysis, PTSs were associated with alterations in LDH measurements, so it is sensible that each hospital validates and monitors their PTSs.

In-depth investigation of turn-around time of full blood count tests requested from a clinical haematology outpatient department in Cape Town, South Africa

BACKGROUND

The performance of laboratories can be objectively assessed using the overall turn-around time (TAT). However, TAT is defined differently by the laboratory and clinicians; therefore, it is important to determine the contribution of all the different components making up the laboratory test cycle.

OBJECTIVE

We carried out a retrospective analysis of the TAT of full blood count tests requested from the haematology outpatient department at Tygerberg Academic Hospital in Cape Town, South Africa, with an aim to assess laboratory performance and to identify critical steps influencing TAT.

METHODS

A retrospective audit was carried out, focused on the full blood count tests from the haematology outpatient department within a period of 3 months between 01 February and 30 April 2018. Data was extracted from the National Health Laboratory Service laboratory information system. The time intervals of all the phases of the test cycle were determined and total TAT and within-laboratory (intra-lab) TAT were calculated.

RESULTS

A total of 1176 tests were analysed. The total TAT median was 275 (interquartile range [IQR] 200.0-1537.7) min with the most prolonged phase being from authorisation to review by clinicians (median 114 min; IQR: 37.0-1338.5 min). The median intra-lab TAT was 55 (IQR 40-81) min and 90% of the samples were processed in the laboratory within 134 min of registration.

CONCLUSION

Our findings showed that the intra-lab TAT was within the set internal benchmark of 3 h. Operational phases that were independent of the laboratory processes contributed the most to total TAT.

Pneumatic tube validation: Reducing the need for donor samples by integrating a vial-embedded data logger

BACKGROUND

The most common way to validate a pneumatic tube system is to compare pneumatic tube system-transported blood samples to blood samples carried by hand. The importance of measuring the forces inside the pneumatic tube system has also been emphasized. The aim of this study was to define a validation protocol using a mini data logger (VitalVial, Motryx Inc., Canada) to reduce the need for donor samples in pneumatic tube system validation.

METHODS

As an indicator of the total vibration, the blood samples are exposed to under pneumatic tube system transportation; the area under the curve was determined by a VitalVial for all hospital Tempus600 lines using a five-day validation protocol. Only the three lines with the highest area under the curves were clinically validated by analysing potassium, lactate dehydrogenase and aspartate aminotransferase. A month after pneumatic tube system commissioning, a follow-up on laboratory data was performed.

RESULTS

Mean area under the curve of the six lines ranged between 347 and 581. The variability of the area under the curve was between 1.51 and 11.55%. In the laboratory data follow-up, an increase in lactate dehydrogenase haemolysis was seen from the three lines with the highest area under the curve and the emergency department, which was not detected in the clinical validation. When the Tempus600 system was in commission, a higher mean area under the curve was measured.

CONCLUSION

A three-day validation protocol using VitalVials is enough to determine the stability of a Tempus600 system and can greatly reduce the need for donor samples. When in commission, the stability of the pneumatic tube system should be verified and lactate dehydrogenase haemolysis should be routinely checked.

Pneumatic tube transport of blood samples affects global hemostasis and platelet function assays

INTRODUCTION

Pneumatic tube systems (PTS) are frequently used for rapid and cost-effective transportation of blood samples to the clinical laboratory. The impact of PTS transport on platelet function measured by the Multiplate system and global hemostasis measured by the TEG 5000 was evaluated.

METHODS

Paired samples from healthy adult individuals were obtained at two study sites: Rigshospitalet (RH) and Nordsjaellands Hospital (NOH). One sample was transported by PTS and one manually (non-PTS). Platelet function was assessed by platelet aggregation (Multiplate) and global hemostasis was assessed by a variety of thrombelastography (TEG) assays. Multiplate (n = 39) and TEG (n = 32) analysis was performed at site RH, and Multiplate (n = 28) analysis was performed at site NOH.

RESULTS

A significant higher agonist-induced platelet aggregation was found for PTS samples compared to manual transport at site NOH (P < .02, all agonists). No significant difference was found at site RH (P > .05, all agonists). For Kaolin TEG, samples transported by PTS showed a significant lower R-time and higher Angle (P < .001). No significant differences in MA and LY30 was found (P > .05). ACT of RapidTEG was significantly reduced (P = .001) and MA of Functional Fibrinogen TEG was significantly increased (P < .001) after PTS transport. No significant impact of PTS was observed for TEG assays with heparinase (P > .05).

CONCLUSIONS

Depending on the type of PTS, transportation by PTS affected platelet aggregation measured by Multiplate. Furthermore, PTS alters TEG parameters possibly reflecting coagulation factors. Clinical laboratories should evaluate the effect of the local PTS on Multiplate and TEG results.

Pneumatic tube transportation of urine samples

Objectives

Pneumatic tube transportation of samples is an effective way of reducing turn-around-time, but evidence of the effect of pneumatic tube transportation on urine samples is lacking. We thus wished to investigate the effect of pneumatic tube transportation on various components in urine, in order to determine if pneumatic tube transportation of these samples is feasible.

Methods

One-hundred fresh urine samples were collected in outpatient clinics and partitioned with one partition being carried by courier to the laboratory, while the other was sent by pneumatic tube system (Tempus600). Both partitions were then analysed for soluble components and particles, and the resulting mean difference and limits of agreement were calculated.

Results

Albumin, urea nitrogen, creatinine, protein and squamous epithelial cells were unaffected by transportation in the Tempus600 system, while bacteria, renal tubular epithelial cells, white blood cells and red blood cells were affected and potassium and sodium may have been affected.

Conclusions

Though pneumatic tube transportation did affect some of the investigated components, in most cases the changes induced were clinically acceptable, and hence samples could be safely transported by the Tempus600 pneumatic tube system. For bacteria, white blood cells and red blood cells local quality demands will determine if pneumatic tube transportation is appropriate.

A Comparison of Four 3-Axis-Accelerometers for Monitoring Hospital Pneumatic Tube Systems

BACKGROUND

Validation of hospital pneumatic tube systems (PTS) is recommended to predict and prevent errors caused by sample hemolysis. 3-Axis accelerometer dataloggers have been successfully implemented as tools for PTS validation, but the most suitable device for such validation has not been investigated. The aim of this study was to evaluate the performance of four commercially available 3-axis accelerometers for PTS validation.

METHODS

PCE-VD3 (PCE), CEM DT-178A (CEM), Extech VB300 (EXT), and MSR 145 (MSR) dataloggers were placed into a single PTS carrier and repeatedly transported through one of three PTS routes. The number and magnitude of accelerations within each PTS route was collected by each device. Deming regression analysis was used to compare device performance.

RESULTS

The MSR datalogger captured the greatest number of g-forces >3 g, 5 g, 10 g, and 15 g, and the greatest magnitude of g-force (26.7 g) relative to the other devices (CEM: 23.0 g, EXT: 23.3 g, PCE: 23.7 g). As a result of increased sampling frequency, the MSR recorded the lowest AUC and the greatest number of g-forces exceeding 3 g relative to the other devices. Subjectively, the data were difficult to extract from 4 tested devices.

CONCLUSIONS

Commercially available dataloggers differ in their ability to detect the number and magnitude of g-forces within PTSs. We recommend that one device be used to perform all PTS evaluations, with baseline evaluations for tolerable AUC, number, and magnitude of g-forces established internally. Lack of harmonization, cumbersome data processing, and time-consuming data analysis are substantial barriers to universal implementation of dataloggers for PTS validation and monitoring.

Blood Sample Transportation by Pneumatic Transportation Systems: A Systematic Literature Review

BACKGROUND

Pneumatic transportation systems (PTSs) are increasingly used for transportation of blood samples to the core laboratory. Many studies have investigated the impact of these systems on different types of analyses, but to elucidate whether PTSs in general are safe for transportation of blood samples, existing literature on the subject was systematically assessed.

METHODS

A systematic literature review was conducted following the preferred reporting items for systematic reviews and metaanalyses (PRISMA) Statement guidelines to gather studies investigating the impact of PTS on analyses in blood samples. Studies were extracted from PubMed and Embase. The search period ended November 2016.

RESULTS

A total of 39 studies were retrieved. Of these, only 12 studies were conducted on inpatients, mainly intensive care unit patients. Blood gases, hematology, and clinical chemistry were well investigated, whereas coagulation, rotational thromboelastometry, and platelet function in acutely ill patients were addressed by only 1 study each. Only a few parameters were affected in a clinically significant way (clotting time parameter in extrinsic system thromboelastometry, pO2 in blood gas, multiplate analysis, and the hemolysis index).

CONCLUSIONS

Owing to their high degree of heterogeneity, the retrieved studies were unable to supply evidence for the safety of using PTSs for blood sample transportation. In consequence, laboratories need to measure and document the actual acceleration forces in their existing PTS, instituting quality target thresholds for these measurements such as acceleration vector sums. Computer modeling might be applied to the evaluation of future PTS installations. With the increasing use of PTS, a harmonized, international recommendation on this topic is warranted.

Comparison of pneumatic tube system with manual transport for routine chemistry, hematology, coagulation and blood gas tests

BACKGROUND

The pneumatic tube system (PTS) is commonly used in modern clinical laboratories to provide quick specimen delivery. However, its impact on sample integrity and laboratory testing results are still debatable. In addition, each PTS installation and configuration is unique to its institution. We sought to validate our Swisslog PTS by comparing routine chemistry, hematology, coagulation and blood gas test results and sample integrity indices between duplicate samples transported either manually or by PTS.

METHODS

Duplicate samples were delivered to the core laboratory manually by human courier or via the Swisslog PTS. Head-to-head comparisons of 48 routine chemistry, hematology, coagulation and blood gas laboratory tests, and three sample integrity indices were conducted on 41 healthy volunteers and 61 adult patients.

RESULTS

The PTS showed no impact on sample hemolysis, lipemia, or icterus indices (all p<0.05). Although alkaline phosphatase, total bilirubin and hemoglobin reached statistical significance (p=0.009, 0.027 and 0.012, respectively), all had very low average bias which ranged from 0.01% to 2%. Potassium, total hemoglobin and percent deoxyhemoglobin were statistically significant for the neonatal capillary tube study (p=0.011, 0.033 and 0.041, respectively) but no biases greater than ±4% were identified for these parameters. All observed differences of these 48 laboratory tests were not clinically significant.

CONCLUSIONS

The modern PTS investigated in this study is acceptable for reliable sample delivery for routine chemistry, hematology, coagulation and blood gas (in syringe and capillary tube) laboratory tests.

Effects of one directional pneumatic tube system on routine hematology and chemistry parameters; A validation study at a tertiary care hospital

Background

The validation of sample stability through pneumatic tube system (PTS) is essential. The objective of this study was to evaluate the effects of PTS transportation on laboratory results.

Methods

Paired EDTA and SST blood samples were collected from 56 randomly selected patients. Laboratory parameters were compared between PTS group and hand-delivered group.

Results

No statistical differences were observed for complete blood counts, white blood cell differential parameters, erythrocyte sedimentation rate and most chemistry parameters between PTS and hand-delivered transport procedures. Mean platelet volume results obtained from samples transported through PTS were lower than that obtained from samples transported through hand-delivered method (P = 0.001). The results of aspartate aminotransferase (P = 0.000), lactate dehydrogenase (P = 0.000), and hemolysis index (P = 0.000) from PTS group were higher than that from hand-delivered group.

Conclusions

All laboratories should validate the stability of the results from samples according to transportation method.

Pre-analytical phase management: a review of the procedures from patient preparation to laboratory analysis

The pre-analytical phase encompasses all the procedures before the start of laboratory testing. This phase of the testing process is responsible for the majority of the laboratory errors, since the related procedures involve many sorts of non-laboratory professionals working outside the laboratory setting, thus without direct supervision by the laboratory staff. Therefore, either correct organization or management of both personnel and procedures that regard blood specimen collection by venipuncture are of fundamental importance, since the various steps for performing blood collection represent per se sources of laboratory variability. The aim of this (non-systematic) review addressed to healthcare professionals is to highlight the importance of blood specimen management (from patient preparation to laboratory analyses), as a tool to prevent laboratory errors, with the concept that laboratory results from inappropriate blood specimens are inconsistent and do not allow proper treatment nor monitoring of the patient.

Extending laboratory automation to the wards: effect of an innovative pneumatic tube system on diagnostic samples and transport time

Background:

The innovative pneumatic tube system (iPTS) transports one sample at a time without the use of cartridges and allows rapid sending of samples directly into the bulk loader of a laboratory automation system (LAS). We investigated effects of the iPTS on samples and turn-around time (TAT).

Methods:

During transport, a mini data logger recorded the accelerations in three dimensions and reported them in arbitrary area under the curve (AUC) units. In addition representative quantities of clinical chemistry, hematology and coagulation were measured and compared in 20 blood sample pairs transported by iPTS and courier.

Results:

Samples transported by iPTS were brought to the laboratory (300 m) within 30 s without adverse effects on the samples. The information retrieved from the data logger showed a median AUC of 7 and 310 arbitrary units for courier and iPTS transport, respectively. This is considerably below the reported limit for noticeable hemolysis of 500 arbitrary units.

Conclusions:

iPTS reduces TAT by reducing the hands-on time and a fast transport. No differences in the measurement results were found for any of the investigated 36 analytes between courier and iPTS transport. Based on these findings the iPTS was cleared for clinical use in our hospital.

Influence of pneumatic tube system transport on routinely assessed and spectrophotometric cerebrospinal fluid parameters

BACKGROUND

Pneumatic tube systems (PTS) are widely used in many hospitals. Using PTS reduces turnaround time (TAT) and can improve patients' outcome.

METHODS

We investigated whether clinically significant differences could be observed in CSF samples transported by pneumatic tube in comparison with samples transported by hand. Two aliquots from one sample were sent by PTS and by hand from the department of neurology or neurosurgery and compared.

RESULTS

Routine cytological and biochemical assessment was compared in 27 cases. There were no statistically significant changes (transport by hand vs. PTS) in glucose levels [data are expressed as median (minimum-maximum)] at 3.7 (2.5-8.6) mmol/L vs. 3.6 (2.7-8.6) mmol/L, p=0.96 or lactate levels at 1.8 mmol/L (1.1-5.5) vs. 1.8 mmol/L (1.1-5.4). We observed a statistically significant decline in total protein levels in samples transported by PTS at 0.56 g/L (0.19-4.29) vs. 0.49 g/L (0.18-4.3), p=0.008. We observed no changes in erythrocyte count at 5/μL (0-40,000) vs. 5/μL (0-40,106), mononuclear cells at 2/μL (1-145) vs. 3/μL (1-152), or polynuclear cells at 0/μL (0-235) vs. 0/μL (0-352). Spectrophotometric examination was performed in 20 cases. There were no statistically significant differences (transport by hand vs. transport by PTS) in NOA at 0.002 (0.001-1.537) vs. 0.001 (0.001-1.528), p=0.95 or NBA at 0.001 (0.001-0.231) vs. 0.001 (0.001-0.276), p=0.675. Samples transported by PTS were delivered faster than samples transported by courier (transport by hand vs. PTS) at 25 min (10-153) vs. 15 min (4-110), p=0.002.

CONCLUSIONS

We found no significant changes in glucose, lactate levels and in any of the cytological parameters assessed, nor were statistically significant changes observed in the spectrophotometric parameters. We found a statistically significant decrease in total protein levels in samples transported by PTS. Transport by PTS can be faster than transport by hand.

Does Pneumatic Tube System Transport Contribute to Hemolysis in ED Blood Samples?

INTRODUCTION

Our goal was to determine if the hemolysis among blood samples obtained in an emergency department and then sent to the laboratory in a pneumatic tube system was different from those in samples that were hand-carried.

METHODS

The hemolysis index is measured on all samples submitted for potassium analysis. We queried our hospital laboratory database system (SunQuest(®)) for potassium results for specimens obtained between January 2014 and July 2014. From facility maintenance records, we identified periods of system downtime, during which specimens were hand-carried to the laboratory.

RESULTS

During the study period, 15,851 blood specimens were transported via our pneumatic tube system and 92 samples were hand delivered. The proportions of hemolyzed specimens in the two groups were not significantly different (13.6% vs. 13.1% [p=0.90]). Results were consistent when the criterion was limited to gross (3.3% vs 3.3% [p=0.99]) or mild (10.3% vs 9.8% [p=0.88]) hemolysis. The hemolysis rate showed minimal variation during the study period (12.6%-14.6%).

CONCLUSION

We found no statistical difference in the percentages of hemolyzed specimens transported by a pneumatic tube system or hand delivered to the laboratory. Certain features of pneumatic tube systems might contribute to hemolysis (e.g., speed, distance, packing material). Since each system is unique in design, we encourage medical facilities to consider whether their method of transport might contribute to hemolysis in samples obtained in the emergency department.

Increased door to admission time is associated with prolonged throughput for ED patients discharged home

BACKGROUND

Emergency Department (ED) service evaluations are typically based on surveys of discharged patients. Physicians/administrators benefit from data that quantifies system-based factors that adversely impact the experience of those who represent the survey cohort.

OBJECTIVE

While investigators have established that admitted patient boarding impacts overall ED throughput times, we sought to specifically quantify the relationship between throughput times for patients admitted (EDLOS) versus discharged home from the ED (DCLOS).

METHODS

We performed a prospective analysis of consecutive patient encounters at an inner-city ED. Variables collected: median daily DCLOS for ED patients, ED daily census, left without being seen (LWBS), median door to doctor, median room to doctor, and daily number admitted. Admitted patients divided into 2 groups based on daily median EDLOS for admits (<6 hours, ≥6 hours). Continuous variables analyzed by t-tests. Multivariate regression utilized to identify independent effects of the co-variants on median daily DCLOS.

RESULTS

We analyzed 24,127 patient visits. ED patient DCLOS was longer for patients seen on days with prolonged EDLOS (193.7 minutes, 95%CI 186.7-200.7 vs. 152.8, 144.9-160.5, P< .0001). Variables that were associated with increased daily median EDLOS for admits included: daily admits (P= 0.01), room to doctor time (P< .01), number of patients that left without being seen (P< .01). When controlling for the covariate daily census, differences in DCLOS remained significant for the ≥6 hours group (189.4 minutes, 95%CI 184.1-194.7 vs. 164.8, 155.7-173.9 (P< .0001).

CONCLUSION

Prolonged ED stays for admitted patients were associated with prolonged throughput times for patients discharged home from the ED.

Heparinate but not serum tubes are susceptible to hemolysis by pneumatic tube transportation

Background:

Pneumatic tube transportation (PTT) may induce hemolysis (H) in blood samples. We aimed to compare the H degree before and after PTT implementation in our hospital.

Methods:

Hemolysis indices (HI) for all lithium-heparin plasma samples (P) drawn by the Emergency Department in 2-month periods were retrospectively collected and pre- (n=3579) and post-PTT (n=3469) results compared. The impact of PTT introduction was investigated on LDH [HI threshold (HIt), 25], conjugated bilirubin (cBIL) (HIt, 30), K (HIt, 100) and ALT (HIt, 125). In addition, HI retrieved for P and paired serum samples collected in silica clot activator tubes (S) from the same venipuncture were compared in pre- (n=501) and post-PTT (n=509) periods.

Results:

Median (5–95th percentile) HI in P was significantly higher in post-PTT period [7 (0–112) vs. 6 (0–82), p<0.001]. Results reported as ‘Hemolysis’ in P increased from 6.6% in pre-PTT to 9.4% in post-PTT (p<0.001). Investigated tests gave the following rejection rates (pre-PTT vs. post-PTT): LDH, 13.4% vs. 18.8%, p<0.001; cBIL, 9.4% vs. 27.0%, p<0.05; K, 3.7% vs. 5.6%, p<0.001; ALT, 2.9% vs. 4.4%, p<0.01. The slightly higher susceptibility to H of S compared to paired P found in the pre-PTT [9 (1–64) vs. 6 (0–85)] was not confirmed in the post-PTT period [7 (0–90) vs. 8 (1–72)], in which median HI in S was significantly lower (p<0.001) than in pre-PTT.

Conclusions:

In our setting PTT promotes H in P, increasing the rate of rejected tests. The use of S appears to protect against the hemolysing effect of PTT.

Laboratory turnaround times in response to an abrupt increase in specimen testing after a natural disaster

OBJECTIVES

Understanding how key indicators change during extreme circumstances could help laboratories maintain high standards when responding to disasters. We assessed the effects of an earthquake on turnaround times (TATs) at a hospital laboratory.

METHODS

We examined TATs for 709,786 potassium tests and 196,795 urine cultures from February 2010 to January 2013. Hospital and community data were evaluated separately and compared during the transport, registration (accessioning), and analysis time phases.

RESULTS

After the earthquake, the laboratory undertook approximately 70% of the nonacute community specimen testing. Initially, community transport times increased by 20 to 27 hours and remained 2 to 3 hours above prequake levels. Registration time increased by 10 to 20 minutes (hospital) and 30 to 45 minutes (community) for a short period. During the initial few months, community urine culture analysis time increased by more than 50 hours.

CONCLUSIONS

The increase in specimen numbers affected short- and long-duration test TATs differently. Streamlining and automating processes reduced registration and analysis times. Increased transport time was outside the control of the laboratory.

Hemolysis associated with pneumatic tube system transport for blood samples

Objective: The frequency of hemolysis of blood samples may be increased by transport in a pneumatic tube system. The purpose of this study was to evaluate the effect of pneumatic tube system transport on hemolysis of blood samples.

Methods: Blood samples were transported from the emergency department to the hospital laboratory manually by hospital staff (49 patients) or with a pneumatic tube system (53 patients). The hemolysis index and serum chemistry studies were performed on the blood samples and compared between the different methods of transport.

Results: The blood samples that were transported by the pneumatic tube system had a greater frequency of hemolysis and greater mean serum potassium and median creatinine, aspartate aminotransferase, and lactate dehydrogenase levels than samples transported manually.

Conclusion: Blood samples transported from the emergency department to the hospital laboratory by a pneumatic tube system may have a greater frequency of hemolysis than samples transported manually. This may necessitate repeat phlebotomy and cause a delay in completing the laboratory analysis.

Monitoring and root cause analysis of clinical biochemistry turn around time at an academic hospital

Quality can be defined as the ability of a product or service to satisfy the needs and expectations of the customer. Laboratories are more focusing on technical and analytical quality for reliability and accuracy of test results. Patients and clinicians however are interested in rapid, reliable and efficient service from laboratory. Turn around time (TAT), the timeliness with which laboratory personnel deliver test results, is one of the most noticeable signs of laboratory service and is often used as a key performance indicator of laboratory performance. This study is aims to provide clue for laboratory TAT monitoring and root cause analysis. In a 2 year period a total of 75,499 specimens of outdoor patient department were monitor, of this a total of 4,142 specimens exceeded TAT. With consistent efforts to monitor, root cause analysis and corrective measures, we are able to decreased the specimens exceeding TAT from 7-8 to 3.7 %. Though it is difficult task to monitor TAT with the help of laboratory information system, real time documentation and authentic data retrievable, along with identification of causes for delays and its remedial measures, improve laboratory TAT and thus patient satisfaction.

Use of butterfly needles to draw blood is independently associated with marked reduction in hemolysis compared to intravenous catheter

OBJECTIVES

Hemolysis of blood samples drawn in the emergency department (ED) is a common problem that can interfere with timely diagnosis and appropriate treatment. The objective of this study was to identify the smallest number of remediable factors that independently increases the risk of hemolysis to design an effective strategy to address this issue.

METHODS

This was a prospective, observational, cross-sectional study of blood specimens obtained by ED staff in an urban, academic, adult ED in a tertiary care center. The staff member who drew the specimen recorded data on a standardized data collection instrument about device (intravenous [IV] catheter or butterfly needle), needle size, anatomic site, fullness of collection tube, tourniquet time, and difficulty of venipuncture. Specimens were sent to the laboratory by a vacuum-powered tube system. A standard automated process that measures free hemoglobin was used to identify hemolysis. A multivariable logistic regression and a tabular analysis stratified by device were performed. Ninety-five percent confidence intervals (CIs) were calculated around the odds ratios (ORs) and around the difference between hemolysis rates.

RESULTS

Data were collected on 5,118 blood specimens. There were 4,513 specimens with complete data on all characteristics of the blood draw included in the analyses. The overall hemolysis rate was 12.5% (95% CI = 11.6% to 13.5%), 14.6% in blood drawn from IV catheters and 2.7% from butterfly needles (difference = 11.9%; 95% CI = 10.2% to 13.4%). Device was the strongest independent predictor of hemolysis (OR = 7.7; 95% CI = 4.9 to 12.0). In specimens drawn by IV catheter, hemolysis was significantly higher when blood was drawn from locations other than the antecubital fossa, with small-gauge catheters, collection tubes ≤ half full, tourniquet time ≥ 1 minute, and difficult venipuncture. In contrast, none of these factors was associated with hemolysis when blood was drawn by butterfly needle.

CONCLUSIONS

The device used to collect blood was the strongest independent predictor of hemolysis in blood samples drawn in the ED in this study. This finding suggests that the most effective strategy to reduce the rate of hemolysis in the ED is to use butterfly needles for phlebotomy rather than IV catheters.

The effects of transport by pneumatic tube system on blood cell count, erythrocyte sedimentation and coagulation tests

Introduction:

Today, the pneumatic tube transport system (PTS) is used frequently because of its advantages related to timing and speed. However, the impact of various types of PTS on blood components is unknown. The aim of this study was to examine the influence of PTS on the quality of routine blood cell counts, erythrocyte sedimentation, and certain blood coagulation tests.

Materials and methods:

Paired blood samples were obtained from each of 45 human volunteers and evaluated by blood cell count, erythrocyte sedimentation, and several coagulation tests, including prothrombin time (PT) and activated partial thromboplastin time (aPTT). Blood samples were divided into 2 groups: Samples from group 1 were transported to the laboratory via the PTS, and samples from group 2 were transported to the laboratory manually. Both groups were evaluated immediately by the tests listed above.

Results:

The blood sample test results from groups 1 and 2 were evaluated and compared. No statistically significant differences were observed (P = 0.069–0.977).

Conclusion:

The PTS yielded no observable effects on blood cell counts, erythrocyte sedimentation, or PT and aPTT test results. We concluded that the PTS can be used to transport blood samples and yield reliable results for blood cell counts, erythrocyte sedimentation, and several coagulation tests.

Effectiveness of practices to reduce blood sample hemolysis in EDs: a laboratory medicine best practices systematic review and meta-analysis

OBJECTIVE

To complete a systematic review of emergency department (ED) practices for reducing hemolysis in blood samples sent to the clinical laboratory for testing.

RESULTS

A total of 16 studies met the review inclusion criteria (12 published and 4 unpublished). All 11 studies comparing new straight needle venipuncture with IV starts found a reduction in hemolysis rates, [average risk ratio of 0.16 (95% CI=0.11-0.24)]. Four studies on the effect of venipuncture location showed reduced hemolysis rates for the antecubital site [average risk ratio of 0.45 (95% CI=0.35-0.57].

CONCLUSIONS

Use of new straight needle venipuncture instead of IV starts is effective at reducing hemolysis rates in EDs, and is recommended as an evidence-based best practice. The overall strength of evidence rating is high and the effect size is substantial. Unpublished studies made an important contribution to the body of evidence. When IV starts must be used, observed rates of hemolysis may be substantially reduced by placing the IV at the antecubital site.

[Pneumatic tube system for blood products transport]

Blood product transport from blood bank to the patient care areas of hospitals is a key step in the transfusion process. The pneumatic tube system is now widely used in hospitals. Strict performance specifications must be respected to guarantee blood safety: robustness, easy to use and respect the constraints imposed to blood products. To secure the disposal of blood products ordered to a carrier (delivery step), a security device must be deployed (video camera, barcode reading, fax, chip), allowing in particular to limit the risk of addressing error when sending (in the case of device with several arrival stations) or picked up by the wrong carrier.

Effect of pneumatic tube delivery system rate and distance on hemolysis of blood specimens

BACKGROUND

We evaluated the effects of pneumatic tube system (PTS) transport rates and distances on routine hematology and coagulation analysis. PTS effects on centrifuged blood samples were also examined.

METHOD

The study was completed at Dicle University Hospital, which has the longest pneumatic tube system in Turkey. Blood samples were collected at three different locations within the hospital and an emergency department, and delivered to the central laboratory by the PTS or a human carrier. Samples were transported at different rates and over varying distances. Each specimen's potassium (K) and lactic dehydrogenase (LDH) levels, in both the serum and plasma, were tracked to monitor hemolysis. Measurements of LDH and K were obtained using heparin or citrate.

RESULT

A positive correlation was observed between distance and hemolysis in serum samples transported at 4.2 m/sec, and at 3.1 m/sec for more than 2200 m (r = 0.774 and r = 0.766, respectively). Distance and hemolysis were also correlated in non-centrifuged samples (r = 0.871). The alterations in plasma LDH and K levels at different rates and PTS lengths were not statistically significant.

CONCLUSION

The rate of hemolysis in PTS transported samples, dependent on PTS length and rate, may seriously affect routine tests of non-centrifuged samples.

Sample transport by pneumatic tube system alters results of multiple electrode aggregometry but not rotational thromboelastometry

Pneumatic tube systems (PTS) present a convenient way for blood sample transport in medical facilities. Associated preanalytical interference in various tests is largely unknown. Implementing point-of-care coagulation management at our institution, we investigated multiple electrode aggregometry (MEA) and rotational thromboelastometry (ROTEM) after PTS transportation. Whole blood samples from patients undergoing general or trauma surgery were analysed by MEA after collection (baseline, '0 × PTS') and sent on a predefined PTS track (n = 12). MEA was repeated after samples travelled the track 4 ('4 × PTS'), 8 ('8 × PTS') and 12 times ('12 × PTS') and compared with stationary controls analysed at the same time. Samples for ROTEM (n = 6) were analysed after collection and travelling the track 12 times. An acceleration detector recorded g-forces on the PTS track. At '0 × PTS' no significant differences in MEA results were detected. Values were significantly lower for transported samples compared with controls ('4 × PTS' to '12 × PTS', p < 0.001). Furthermore, MEA results of PTS samples were significantly decreased for '4 × PTS' to '12 × PTS' compared to baseline (p < 0.001). Except for the clotting time in EXTEM PTS transport did not significantly alter results for investigated ROTEM parameters, compared with baseline and stationary controls. Acceleration detector readout revealed alternating g-forces between -6.3 and +5.9 during transport. PTS transport caused invalid results in MEA while only one ROTEM parameter was found to be affected in this study. Variable acceleration during transport provides a potential reason for platelet activation. The authors recommend sample transport by hand or the device to be placed patient-side when MEA is performed.

Pseudohyperkalaemia associated with leukaemic cell lysis during pneumatic tube transport of blood samples

BACKGROUND

Pseudohyperkalaemia is relatively uncommon in children, but needs to be considered in cases where extreme hyperkalaemia is associated with normal renal function.

CASE

A previously well 12 year-old boy presented with new onset T cell acute lymphoblastic leukaemia associated with a high peripheral blood white cell count. Plasma biochemistry tests on a blood sample sent to the laboratory using a pneumatic tube system showed a high plasma potassium level of 16.6 mmol/l, with otherwise normal electrolytes and renal function. A 12-lead electrocardiogram was normal, with no changes suggestive of hyperkalaemia. Pseudohyperkalaemia was suspected, and further samples transported to the laboratory by foot showed normal plasma potassium levels. It was subsequently demonstrated that the pseudohyperkalemia was due to the lysis of leukaemic white cells during the transport of blood samples from the ward to the laboratory within the pneumatic tube system.

CONCLUSIONS

Paediatricians caring for children with haematological malignancies need to be aware of this cause of pseudohyperkalaemia so that unnecessary treatment, including the commencement of acute dialysis, is avoided. We recommend that blood samples collected from children with high white cell count malignancies are transported to the laboratory by foot rather than in pneumatic tube systems.

Determination of Hemolysis Thresholds by the Use of Data Loggers in Pneumatic Tube Systems

BACKGROUND

Pneumatic tube systems (PTSs) for the transport of blood samples are regaining popularity in medical centers after earlier reports that their use could introduce preanalytical distortions such as hemolysis and changes in blood gases.

METHODS

We drew duplicate blood samples from 30 volunteers. One sample was hand transported, and the other sample was transported through a PTS together with a mini–data logger that provided continuous measurements of temperature, humidity, pressure, and acceleration. After transport the samples were analyzed at the same time. We looked for possible relationships of the transport method and the parameters measured by the data loggers with differences in hematological parameters, standard clinical chemistry analyses, blood coagulation, erythrocyte sedimentation rate, and blood gas analysis.

RESULTS

There were no significant differences in temperature, humidity, and pressure between the methods of transport, but we observed significant differences in 3-axis accelerations. The combined effect of these forces could be described by the right-tailed area under the vector sum acceleration distribution. Our data show that this area correlated with PTS speed and that PTS speed and the area under the curve exhibited a direct relation to the degree of hemolysis.

CONCLUSIONS

Assessment of 3-axis acceleration by use of data loggers can be used to identify preanalytical deviations that result from the transportation of blood samples in PTSs. Our approach could be used for the evaluation and regular control of PTSs without the need for repeated blood drawing and laboratory analyses.

Mapping turnaround times (TAT) to a generic timeline: a systematic review of TAT definitions in clinical domains

BACKGROUND

Assessing turnaround times can help to analyse workflows in hospital information systems. This paper presents a systematic review of literature concerning different turnaround time definitions. Our objectives were to collect relevant literature with respect to this kind of process times in hospitals and their respective domains. We then analysed the existing definitions and summarised them in an appropriate format.

METHODS

Our search strategy was based on Pubmed queries and manual reviews of the bibliographies of retrieved articles. Studies were included if precise definitions of turnaround times were available. A generic timeline was designed through a consensus process to provide an overview of these definitions.

RESULTS

More than 1000 articles were analysed and resulted in 122 papers. Of those, 162 turnaround time definitions in different clinical domains were identified. Starting and end points vary between these domains. To illustrate those turnaround time definitions, a generic timeline was constructed using preferred terms derived from the identified definitions. The consensus process resulted in the following 15 terms: admission, order, biopsy/examination, receipt of specimen in laboratory, procedure completion, interpretation, dictation, transcription, verification, report available, delivery, physician views report, treatment, discharge and discharge letter sent. Based on this analysis, several standard terms for turnaround time definitions are proposed.

CONCLUSION

Using turnaround times to benchmark clinical workflows is still difficult, because even within the same clinical domain many different definitions exist. Mapping of turnaround time definitions to a generic timeline is feasible.

Agreement between paired blood gas values in samples transported either by a pneumatic system or by human courier

Rapid accurate assessment of metabolic derangements is crucial in the critically ill. We evaluated if arterial blood gas (ABG) samples transported through a pneumatic tube system (PTS) agreed with values transported by a human courier.

In this prospective study of 50-paired ABG samples, the couriered reference ABG was compared with those transported by PTS. Agreement was summarised by the mean difference with 95% limits of agreement (LOA) and Lin's concordance correlation (

The mean (±SD) time from sampling to analysis was 35.7±23.2 (courier) and 38.6±22.1 (PTS) minutes. Agreement was good between courier and PTS for pH, PaCO

In this study, analysis of samples transported through the PTS resulted in clinically unacceptable PaO