Introduction

The use of platelets is relevant in treating coagulation disorders and managing bleeding caused by thrombocytopenia [1]. Obtaining platelet concentrates (PC) in blood banks (BB) uses various methods, the best known being those based on sedimentation-centrifugation or apheresis [2]. The first is most used in health establishments as the latter needs specific infrastructure and high technology. Sedimentation-centrifigation process is longer, more laborious, and involves greater participation in human manual activity than apheresis [3]. This situation can generate CP unsuitable for heme therapeutic procedures due to non-compliance with quality indicators established by the BB [4]. Transfusion and BB services must ensure optimal use of blood components and ensure that the final product causes minimal or no risk to the potential recipient. Internal quality control is crucial for a quality management system at the BB and involves having blood products available in a timely manner [5].

In Peru, there are few studies that address quality control of BBs. A decrease in the supply of blood products has been observed in high-complexity hospitals [6]. In relation to the quality of PC, plateletpheresis has been demonstrated as the most effective procedure to obtain platelets [7]. However, it is not known about the quality of PC obtained by manual processes. The BB of Peru is aligned with policies established by the National Program of Hemotherapy and Blood Banks, which defines the objectives that must be achieved in these institutions [8]. One of the strategic objectives of National Program of Hemotherapy and Blood Banks is to improve the quality of supplies generated in hemotherapy centers and BBs. However, as long as compliance with the quality indicators defined within a quality management system is not evident, nonconformities will affect the service and users [9].

The recommended shelf life of PC in storage bags is approximately five days at 22 ± 2°C with continuous agitation. Platelets undergo several processes with changes starting from collection, processing, storage, and underlying conditions in patients, which can affect the therapeutic benefit to the recipient [10]. Changes in platelet metabolic activity play a crucial role in PC quality, mainly due to changes in pH [11]. However, these are not the only parameters that should be considered to evaluate the quality of PC. Evaluating the quality of PC is a vital, using specific parameters such as the presence of the swirling effect, volume, count of platelets and leukocytes per bag, and pH changes [12].

Our objective was to determine the total compliance rate in PC obtained in the Blood Bank of the Cayetano Heredia Hospital in November and December of 2019. We consider that our study provides relevant information for continuous quality improvement processes in blood banks, specifically in PC management.

Methods

Study design and population

We designed a cross-sectional study to evaluate PC quality indicators from voluntary blood donors. The PC was obtained at the Blood Bank of the Cayetano Heredia Hospital in Lima between November and December 2019. This hospital is the largest in the northern area of Lima, the capital of Peru. The hospital has a hemotherapy center and blood bank classified as type II by the Peruvian Ministry of Health. According to the care records at the blood bankproduces 25 to 30 PC per day, with an average monthly production of 900 concentrates. We included PC obtained by the buffy coat procedure established in the blood bank of the Cayetano Heredia Hospital (see supplementary material 1) and from donors not reactive to the seven serological markers in the blood bank. We excluded PC obtained by apheresis or another procedure.

The number of PC to be evaluated was estimated with a simple proportion calculation in a finite population, assuming a confidence and precision level of 95% and 5% respectively and an expected proportion of nonconformity for platelet concentrates of 10%. Likewise, we considered an ineligible rate of 10%, obtaining a quantity of 133 PC.

Techniques and instruments

Results

We evaluated 133 randomly selected platelet units during November and December 2019. The platelet count had an average of 6.66 ± 3.94 x 1010/µL, and the platelet concentrates had an average of 56.30 ± 6.22 mL. All PCs had the presence of the Swirling phenomenon. The pH had a mean of 7.64 ± 0.15, while the leukocyte counts of 4.22 ± 3.51 x 10⁷/µL (Table 2).

We found that four of the five parameters evaluated were met according to the defined criteria. The platelet count was the only parameter that did not meet the quality standards, with 56.4% of PCs needing compliance. The Swirling effect and pH had absolute compliance in their indicators (Table 3).

Finally, the global analysis showed that only 54.9% (95% CI: 46.0 to 63.5) of the units complied with the National Program of Hemotherapy and Blood Banks standards.

Discussion

The compliance rate of PC is essential data within the quality control of blood products obtained in the BBs. In our case, the results show that approximately 55% of the platelet concentrates meet all the parameters according to PRONAHEBAS. However, it is essential to emphasize that failure to comply with these parameters is not an indicator for discarding units. However, they are considered to improve the process of obtaining and preserving platelets [14]. Within the five parameters that we used to define "compliant platelet concentrate", some had 100% compliance, independently of the rest of the parameters. Likewise, some units presented average platelet counts above what was evidenced in other studies. We reported an average platelet count of 6.66 ± 3.94 x 10¹⁰, while Raturi et al. found an average of 5.89 ± 1.28 (3.1 to 8.7) × 10¹⁰ [15]. On the other hand, regarding the residual leukocyte count, our results show higher counts (4.22 ± 3.51 x 10⁷) compared to the referenced study, whose average was 1.5 ± 1.2 × 10⁷. The swirling effect was present in all the units similar to our study [15].

It is essential to mention that, in our study, the method for obtaining PC was by Buffy coat, which generates platelet counts very different from other methods, such as obtaining platelet-rich plasma or apheresis. Singh et al. evaluated PC of platelet-rich plasma, buffy coat, and apheresis, showing that the mean platelet count was 7.6 ± 2.97 × 10¹⁰/unit, 7.3 ± 2.98 × 10¹⁰/unit, and 4.13 ± 1.32 × 10¹¹/unit, respectively [16]. In that sense, our findings are similar to those obtained in other studies.

Different studies have shown compliance rates above 95% regarding compliance with quality standards, as evidenced by Bouslama et al. in 475 PC obtained by sedimentation and apheresis. However, the platelet count showed compliance in 58% of their concentrates [17], a figure close to that estimated in our study (55% compliance). These results are even more aligned to what was found by Álvarez and Cueva in a study on 384 PC, whose platelet count compliance was 50.8%. Regarding compliance with parameters such as pH, volume, and swirling effect, they obtained rates of 90.1%, 99.5%, and 97.1%, respectively [18]; while we obtained rates of 100.0%, 97.7%, and 100.0%, evidencing much higher percentages.

Within the study’s limitations, given the high demand for PC, evaluations could not be carried out on consecutive days, which would have been ideal to assess the changes in each parameter over time. Nor could probabilistic comparisons be established, considering that only one method was used to obtain platelets. Likewise, carrying out microbiological culture as a quality parameter to verify the products' safety was not possible. However, no adverse event was reported after each platelet concentrate was administered, which is consistent with previous studies [19,20].

It is essential to inform that during the COVID-19 pandemic, the Peruvian Government issued various decrees that progressively resumed economic activities. Care activities through health facilities were not suspended, and blood banks provided continuous care. However, voluntary blood donation campaigns decreased significantly, but replacement donations did not. The last regulation in blood banking was DS 017-2022-MINSA, which modifies the Regulation of Law No. 26454, which declares obtaining, donating, conserving, transfusion and blood supply to be of public order and national interest. However, this standard only requires changes in the organization of blood banks according to the levels of care in health facilities. In the case of our study, the blood bank is located in a level III hospital, whose characteristics did not change with the prerogatives of the standard above.

Finally, this study constitutes essential evidence in the quality control process of the blood bank of the Cayetano Heredia Hospital in Lima, and its results should serve to implement corrective and preventive actions as part of the continuous improvement of the service.

Conclusions

The total compliance rate in PC is moderate and requires improvement actions in the leukoreduction procedure and platelet count. The quality management areas must identify the causes of the parameters whose compliance rate was low, and for this, we recommend using Six Sigma [21] or the Ishikawa method [22]. Finally, it is crucial to guarantee the maintenance and calibration of equipment involved in obtaining CP, especially considering quality standards such as ISO 9001 or 15189 [23,24]. It is important to implement training and updating programs in good manufacturing and quality control practices for BB personnel.