Neonatal Intensive Care Unit Quality Initiative: Identifying Preanalytical Variables Contributing to Specimen Hemolysis and Measuring the Impact of Evidence-Based Practice Interventions

Clinical implications of inaccurate potassium determination in hemolyzed pediatric blood specimens

BACKGROUND

Analysis of whole blood specimens is rapid and saves blood, but hemolysis may go undetected and compromise the accuracy of potassium measurement. We aimed to define the frequency and magnitude of error in whole blood potassium measurement.

METHODS

34 months of whole blood and plasma potassium data were extracted from patients aged less than 2 years at the time of sample acquisition. Hemolysis was detected using the plasma "H index." The magnitude of potassium bias was estimated from the difference between paired whole blood and plasma measurement separated by less than 2 h.

RESULTS

56,000 of the 105,000 data points were from plasma and 20 % of these had significant hemolysis. Rates of hemolysis (nearing 50 %) were greatest in the neonatal nursery. Of 662 proximal whole blood and plasma paired results, 8 % had elevated whole blood potassium with a normal plasma value and 4 % had a normal whole blood potassium with reduced plasma potassium. The bias between whole blood and plasma potassium ranged from -1.0 to 4.0 mmol/L.

CONCLUSIONS

The use of whole blood analysis brings with it significant risk for error in potassium measurement. Better tools to detect hemolysis in these types of specimens are indicated.

Comparison of Clinical, Economic, and Humanistic Outcomes Between Blood Collection Approaches: A Systematic Literature Review

BACKGROUND

A systematic literature review was performed to understand the prevalence, advantages, and disadvantages of blood collection using different approaches (direct venipuncture or vascular access devices), and interventions used to mitigate the disadvantages.

METHODS

The review included a broad range of study designs and outcomes. Database searches (Embase, MEDLINE, Cochrane library, and Centre for Reviews and Dissemination) were conducted in March 2021 and supplemented by hand searching.

RESULTS

One hundred forty-one publications were included. The data indicate that blood sampling from vascular access devices is common in emergency departments, trauma centers, and intensive care units. Studies showed that hemolysis and sample contamination place a considerable economic burden on hospitals. Significant cost savings could be made through enforcing strict aseptic technique, or using the initial specimen diversion technique.

CONCLUSIONS

Hemolysis and sample contamination are far from inevitable in vascular access device-collected or venipuncture samples; both can be reduced through adherence to strict blood sampling protocols and utilization of the initial specimen diversion technique. Needle-free blood collection devices offer further hope for reducing hemolysis. No publication focused on the difficult venous access population; insertion success rates are likely to be lower (and the benefits of vascular access devices higher) in these patients.

Distribution of videos demonstrating best practices in preventing hemolysis is associated with reduced hemolysis among nurse-collected specimens in hospitals

BACKGROUND

Minimizing hemolysis during phlebotomy ensures accurate chemistry results and reduces test cancellations and specimen recollections. We developed videos demonstrating best practices to reduce hemolysis and tested whether distribution to clinical nurse educators (CNEs) for provision to nursing staff affected the degree of specimen hemolysis in hospital inpatient units and outpatient clinics.

METHODS

Videos of common blood collections demonstrating best practices to reduce hemolysis were filmed and then distributed via email link to all hospital-based CNEs in Calgary, Alberta, Canada. (https://vimeo.com/user18866730/review/159869683/a0cec9827f). Roche Cobas hemolysis index (H-index) results from specimens collected +/- 12 months from the date of video distribution were extracted from Roche Cobas IT middleware (cITM) and linked to collection location. An interrupted time series (ITS) analysis with collection location as the unit of anlaysis was used to quantify impact of video distribution on the trajectory of weekly mean log-H-index weighted by inverse variance.

RESULTS

In +/- 3 months of data flanking video distribution (n = 137 241 collections), where overall impact was strongest, H-index trajectory (change in units per week) decreased immediately following video distribution (-5.7% / week, p < 0.01). This was accompanied by a 22% drop in overall H-index from the week before to the week after video distribution (y-intercept change, or gap). There was also a small but significant overall decrease in the proportion of hemolyzed specimens (-0.3%, p < 0.01). These changes were not observed at all collection locations, and in fact increases occured at some locations.

CONCLUSIONS

We developed a novel and convenient educational aid that, when distributed, was associated with beneficial changes in specimen hemolysis at hospital inpatient units and outpatient clinics. Including it in ongoing nursing education will fill a knowledge gap that may help to reduce specimen hemolysis.

Clotted blood samples in the neonatal intensive care unit: A retrospective, observational study to evaluate interventions to reduce blood sample clotting

BACKGROUND

Blood draws for laboratory investigations are essential for patient management in neonatal intensive care units (NICU). When blood samples clot before analysis, they are rejected, which delays treatment decisions and necessitates repeated sampling.

AIMS

To decrease the incidence of rejected blood samples taken for laboratory investigation as a result of clotted sample.

STUDY DESIGN

This retrospective observational study used routine data on blood draws from preterm infants collected between January 2017 and June 2019 in a 112-cot NICU in Qatar. Quality improvement interventions to reduce the rate of clotted blood samples included: awareness raising and safe sampling workshops with NICU staff, involvement of the neonatal vascular access team, development of a complete blood count (CBC) sample collection pathway, review of sample collection equipment, introducing the Tenderfoot® heel lance, establishment of benchmarks and provision of dedicated blood extraction equipment.

RESULTS

First attempt blood draw occurred in 10 706 cases, representing a 96.2% success rate. In 427 (3.8%) cases, the samples were clotted requiring repeat collection. The overall rate of clotted specimens decreased from 4.8% in 2017 and 2018 to 2.4% in 2019, with odds ratios of 1.42 (95% confidence interval [CI] 1.13-1.78, p = .002), 1.46 (95% CI 1.17-1.81, p < .001) and 0.49 (95% CI 0.39-0.63, p < .001), respectively. The majority (87%-95%) of blood samples were by venepuncture using an intravenous (IV) catheter or the NeoSafe™ blood sampling device. Heel prick sampling was the second (2%-9%) most common method. Clotted samples were most frequently associated with needle use, 228 of 427 (53%), and IV cannula, 162 of 427 (38%), with odds ratios of 4.14 (95% CI 3.34-5.13, p < .001) and 3.11 (95% CI 2.51-3.86, p < .001), respectively.

CONCLUSIONS

Our interventions over 3 years were associated with reduced rates of sample rejection due to clotting, and this led to improved patient experience through fewer repeated samplings.

RELEVANCE TO CLINICAL PRACTICE

The insights gained from this project can help to improve patient care. Interventions that reduce the rate of blood sample rejection by clinical laboratories can lead to economic savings, timelier diagnostic and treatment decisions, and contribute to an improved quality care experience for all critical care patients, irrespective of age, by reducing the need for repeated phlebotomy and the risk of related complications.

Blood specimen rejection rate in clinical laboratory: A systematic review and meta-analysis

Background

Clinical laboratory errors have a great impact on patient safety and treatment. Although specimen rejections result in longer turnaround times and increased health-care costs, different studies present inconsistent findings. Therefore, the study aimed to determine the pooled prevalence of blood specimen rejection in clinical laboratory.

Methods

Electronic databases including MEDLINE, PubMed, EMBASE, HINARI, Cochrane Library, Google Scholar, and Science Direct were comprehensively searched. Articles were screened and the data extracted independently by authors. Publication bias was checked by funnel-plots and Egger's statistical test. Pooled prevalence was estimated using a random-effects model. The I² statistical test were performed to assess heterogeneity. The possible sources of heterogeneity were analyzed through subgroup and sensitivity analysis.

Results

Total of 26 articles with 16,118,499 blood sample requests were included in the meta-analysis. The pooled prevalence of blood specimen rejection in the clinical laboratory was 1.99% (95% CI: 1.73, 2.25). Subgroup analysis showed that, the highest prevalence of specimen rejection was observed in Asia [2.82% (95%CI: 2.21, 3.43)] and lowest in America [0.55% (95%CI: 0.27, 0.82)]. The leading cause of blood specimen rejection in clinical laboratories were clotted specimen (32.23% (95%CI: 21.02, 43.43)), hemolysis (22.87% (95%CI: 16.72, 29.02)), insufficient volume (22.81% (95%CI: 16.75, 28.87)), and labelling errors (7.31% (95%CI: 6.12, 8.58)).

Conclusion

The pooled prevalence of blood specimen rejection rate is relatively high especially in developing regions. Therefore, proper training for specimen collectors, compliance with good laboratory practices specific to specimen collection, transportation, and preparation is required to reduce the rejection rate.

The incidence rate and influence factors of hemolysis, lipemia, icterus in fasting serum biochemistry specimens

Objective

Hemolysis, icterus, and lipemia (HIL) of blood samples have been a concern in hospitals because they reflect pre-analytical processes’ quality control. However, very few studies investigate the influence of patients’ gender, age, and department, as well as sample-related turnaround time, on the incidence rate of HIL in fasting serum biochemistry specimens.

Methods

A retrospective, descriptive study was conducted to investigate the incidence rate of HIL based on the HIL index in 501,612 fasting serum biochemistry specimens from January 2017 to May 2018 in a tertiary university hospital with 4,200 beds in Sichuan, southwest China. A subgroup analysis was conducted to evaluate the differences in the HIL incidence rate by gender, age and department of patients, and turnaround time of specimens.

Results

The incidence rate of hemolysis, lipemia and icterus was 384, 53, and 612 per 10,000 specimens. The male patients had a significantly elevated incidence of hemolysis (4.13% vs. 3.54%), lipemia (0.67% vs. 0.38%), and icterus (6.95% vs. 5.43%) than female patients. Hemolysis, lipemia, and icterus incidence rate were significantly associated with the male sex with an odds ratio (OR) of 1.174 [95% confidence interval (CI), 1.140–1.208], 1.757 (95%CI: 1.623–1.903), and 1.303 (95%CI: 1.273–1.333), respectively, (P<0.05). The hospitalized patients had a higher incidence of hemolysis (4.03% vs. 3.54%), lipemia (0.63% vs. 0.36%), and icterus (7.10% vs. 4.75%) than outpatients (P<0.001). Specimens with relatively longer transfer time and/or detection time had a higher HIL incidence (P<0.001). The Pediatrics had the highest incidence of hemolysis (16.2%) with an adjusted OR (AOR) of 4.93 (95%CI, 4.59–5.29, P<0.001). The Neonatology department had the highest icterus incidence (30.1%) with an AOR of 4.93 (95%CI: 4.59–5.29, P<0.001). The Neonatology department (2.32%) and Gastrointestinal Surgery (2.05%) had the highest lipemia incidence, with an AOR of 1.17 (95%CI: 0.91–1.51) and 4.76 (95%CI: 4.70–5.53), both P-value <0.001. There was an increasing tendency of hemolysis and icterus incidence for children under one year or adults aged more than 40.

Conclusion

Evaluation of HIL incidence rate and HIL-related influence factors in fasting serum biochemistry specimens are impartment to interpret the results more accurately and provide better clinical services to patients.

Impact of managing affected results in haemolysed samples of an infant-maternity hospital using an unconventional approach

BACKGROUND

The management of affected results in haemolysed samples (HS) is debated. In an infant-maternity setting, for reporting interfered test results, we provided the result itself, the degree of haemolysis (as free haemoglobin concentration), and a warning recommending sample recollection. We investigated the impact of this approach on sample quality and clinicians' decision-making.

METHODS

Free haemoglobin was measured on Beckman Coulter AU680 as haemolytic index. We estimated the total HS number, the clinical wards more affected by HS, the most interfered analytes, and the retesting rate of interfered tests, by comparing data from Apr-Dec 2017, the period just after the introduction of the new policy, vs. Apr-Dec 2018.

RESULTS

One year after the new report introduction, a significant HS decrease (5.8% vs. 7.8%, P < 0.001) was detected, together with a reduction of the frequency by which haemolysis affected results. The most affected wards, i.e., Paediatric and Neonatal Intensive Care Units, showed an improvement in sample quality (HS rate, 30.6% to 16.1%, P < 0.001, and 25.2% to 20.9%, P = 0.048, respectively). We noted a significant decrease in retesting after an alerted result for aspartate aminotransferase, magnesium, potassium, conjugated bilirubin, and lactate dehydrogenase.

CONCLUSIONS

Our approach led to a HS decrease, suggesting that the provided report could be a driving force for improvement of phlebotomy quality, also helping clinicians in deciding if retesting is essential or not.

A Comparative Study of Blood Sampling From Venipuncture and Short Peripheral Catheters in Pediatric Inpatients

This prospective, comparative study examined blood test results, hemolysis rates, and patient perceptions related to 2 blood sampling methods in pediatric inpatients (N = 95). Blood specimens were drawn via venipuncture and a short peripheral catheter used for fluid administration. Results revealed no significant differences in potassium and glucose levels. No clinically significant difference in hemoglobin was noted. Hemolysis rates were 4% for venipuncture samples and 15% when drawn from peripheral catheters. One catheter became occluded after a blood draw. Patients/parents rated distress and dissatisfaction with venipuncture as significantly greater compared with short peripheral catheter blood sampling (P < .001).

Hemolyzed Specimens: Major Challenge for Identifying and Rejecting Specimens in Clinical Laboratories

Pre-analytical quality in clinical chemistry testing is as important as analytical and post-analytical quality. The most prevalent pre-analytical interference and a major source of error producing unreliable laboratory test results is hemolysis of blood samples. In vitro hemolysis may be due to the blood withdrawal technique or sample handling whereas in vivo hemolysis can originate from acquired, hereditary, or iatrogenic conditions and is not technique dependent. Interpreting in vivo or in vitro hemolysis requires clinicians to supply reliable clinical history and findings. Even then, to reject or release the result with interpretation is still under debate. Thus, hemolyzed specimens are a serious pre-analytical problem calling for well-designed and strictly implemented laboratory guidelines. The aim of this non-systematic review (addressed to healthcare professionals) was to highlight the challenges in identifying and rejecting hemolysis specimens.

Robustness of the Reichert Unistat Bilirubinometer for analysis of hemolyzed samples from neonates

BACKGROUND AND OBJECTIVES

Bilirubin is routinely measured in neonates to avoid the irreversible effects of kernicterus. Grossly hemolyzed samples are routinely rejected under the assumption that bilirubin cannot be accurately measured in hemolyzed samples. The objective of this study was to determine the effect of hemolysis on bilirubin measurement in neonates.

METHODS

Data included 2-years of paired bilirubin results (n=70) where hemolyzed and non-hemolyzed samples were collected and measured within 6h of each other. Bilirubin results were compared by Passing-Bablock linear regression and difference plots. Bilirubin results were also compared using the Bhutani nomogram to determine if hemolysis affected the hyperbilirubinemia risk-category.

RESULTS

Gross hemolysis resulted in a mean negative bias of -5.2μmol/L (95% CI: -30.7 to 20.3μmol/L). Based on the Bhutani nomogram, 1/70 samples would have been classified as Low-intermediate instead of High-intermediate risk and 3/70 would have been classified as Low instead of Low-intermediate risk; 5/70 samples would have been classified as Low-intermediate instead of Low risk.

CONCLUSIONS

Collectively the data support that neonatal bilirubin may be reported from grossly hemolyzed samples measured using the Reichert Unistat Bilirubinometer. This practice has been adopted at our institution where results are reported with comments describing the effects of hemolysis. Implementation of this approach has decreased the number of blood re-collections in neonates.