Abstract
Background
General guidelines describing the potential indications and contraindications of Fresh Frozen Plasma (FFP) exist. However, their implementation is inadequate, leading to inappropriate use in various clinical settings. This study aims to define the appropriateness of the FFP usage in terms of therapeutic versus prophylactic indications.
Methods
Retrospective audit was conducted over one year prior to and after an educational intervention (1122 patients for 6072 FFP units and 1061 patients for 4858 FFP units, respectively). Clinical diagnosis, indication for FFP transfusion, and coagulation profile were noted, and episodes of transfusion were divided into appropriate and inappropriate based on the guidelines of the British Committee for Standards in Hematology (2004 reviewed in 2018) and College of American Pathologists (1994).
Results
Initial audit found 51.8% of FFP transfusions to be inappropriate (3069 of 5922). Coagulation profile (with INR values less than 1.5 times of the normal) was the most common cause of inappropriate transfusion (15.08%). 56.7% of FFP were prophylactically transfused. Re-audit after educational interventions showed a 22.3% reduction in the number of inappropriate transfusions.
Conclusion
Inappropriate, as well as high prophylactic usage of FFP, was noticed in the initial audit, which reduced significantly after educational interventions. Regular CMEs, interactive sessions with clinicians, functioning Hospital Transfusion Committees, and prospective audits can affirm, further improve and reinforce the existing Hospital Transfusion Guidelines.
Keywords: Fresh frozen plasma, Audit, Guidelines, Inappropriate transfusion
Introduction
The advent of component preparation from whole blood (WB) in 1960 has led to increased efficacy and economical utilization of the blood supply, wherein a single WB unit is separated into packed red cells (PRBC), random donor platelets (RDP), and fresh frozen plasma (FFP). FFP mandates separation from WB within 6–8 h of collection and storage at −18 °C or lower as early as possible as it contains the heat labile factors V and VIII along with all other coagulation factors and other plasma proteins.1,2 FFP is on the WHO Model List of Essential Medicines that are the most important medications needed in a basic health care system.3
FFP is a precious therapeutic resource exclusively obtained from humans, either from WB or by apheresis. Commercial use of plasma has also significantly increased in the past 10 years due to its use in plasma fractionation to obtain purified albumin and immunoglobulins.2,4
In clinical practice, FFP is mainly utilized to achieve hemostasis when there is a deficiency of clotting factors, evidence of coagulopathy, or ongoing bleeding due to various other causes. However, the indications are very limited as per existing guidelines from the College of American Pathologists (CAP) [Table 1],5 and the British Committee for Standards in Hematology (BCSH) [Table 2]6,7 Nevertheless, studies from all over the world report a high frequency of inappropriate utilization of FFP.8, 9, 10, 11
Table 1.
FFP transfusion guidelines, college of american pathologists, 1994.5
|
Table 2.
FFP transfusion guidelines as per british committee for standards in hematology 2004 and 2018 (review).7,6
|
Inappropriate FFP transfusion not only squeezes the limited blood bank resources but also exposes the recipient to various risks associated with FFP transfusion.12,13
Auditing the use of blood and component transfusions based on promulgated guidelines is essential to evaluate transfusion practices at the institutional level. This will help in identifying instances of inappropriate blood component usage and induction of corrective actions.1Thus, we took up a retrospective analysis of FFP demands and its rational usage, both prior to and after educational interventions, with the specific aim of finding out its appropriateness on the basis of clinical indications, coagulation profile, amount of FFP transfused, and therapeutic versus prophylactic transfusions.
Materials and methods
Component demands of 1122 patients for FFP received in our blood bank from Nov 2017 to Nov 2018 were retrospectively analyzed using Microsoft Excel 10. Thereafter educational interventions in the form of faculty lectures by Transfusion Medicine specialist for all clinicians, including residents, one to one interaction with some clinicians, discussions in the Hospital Transfusion Committee (HTC) and disseminating the results of the initial audit through HTC to various stakeholders and modification of the Transfusion Demand Form (TDF) were undertaken during Dec 2018 and subsequent months. A detailed TDF was made incorporating all the valid indications for various components, and the clinician simply had to tick the indication for transfusion. If no indication was ticked or any other reason was mentioned, the demand was considered inappropriate. A repeat audit was done on FFP demands received for 1061 patients from Jan 2019 to Dec 2019. The following data were collected: clinical diagnosis, indication for FFP/justification of request, the specialty of the requesting clinician, the demographic data, including age and gender of the patient, number of units transfused and, patient’s pretransfusion international normalized ratio (INR). The usage of FFP was divided into appropriate and inappropriate, therapeutic and prophylactic,after scrutinizing the FFP demand forms for clinical indications, justification of requests, and whether it complied with the existing guidelines published by the College of American Pathologists (CAP 1994), and the British Committee for Standards in Hematology (BCSH 2004 reviewed in 2018).5, 6, 7
Transfusion of 10–15 ml/kg body weight of the recipient was considered optimal dose, which was fulfilled by all the subspecialties. One FFP unit comprises 0.7–1.0 IU/ml of each coagulation factor and 1–2 mg/ml of fibrinogen. An increment of at least 30% of the baseline value in clotting factors is expected after adequate dosage in the absence of rapid and ongoing consumption.5 Institutional Ethics Committee approval was taken for the study.
Results
A total of 6072 units of fresh frozen plasma were issued for 1122 patients in the initial audit. The general medicine department requested the maximum number of FFP, followed by Oncology/Oncosurgery and Cardiothoracic surgery departments. Specialty-wise demands for both audits are elaborated in Table 3.
Table 3.
Comparison between FFP utilization before and after an educational intervention.
| Name of specialty | Number of patients before educational campaign (%) | Number of patients after educational campaign (%) | Number of FFP transfused before educational campaign (%) | Number of FFP transfused after educational campaign (%) |
|---|---|---|---|---|
| General medicine | 220 (19.6) | 188 (17.7) | 1325 (21.8) | 973 (20) |
| Oncology and onco surgery | 170 (15.1) | 168 (15.8) | 1045 (17.2) | 791 (16.2) |
| CTVS | 140 (12.4) | 153 (14.4) | 868 (14.2) | 816 (16.8) |
| General surgery | 122 (10.8) | 104 (9.8) | 578 (9.5) | 420 (8.6) |
| Nephrology | 85 (7.6) | 38 (3.5) | 522 (8.6) | 196 (4.0) |
| GI surgery | 79 (7.0) | 65 (6.1) | 349 (5.7) | 263 (5.4) |
| Neurosurgery | 68 (6) | 70 (6.5) | 341 (5.6) | 348 (7.1) |
| Clinical hematology | 35 (3.1) | 48 (4.5) | 234 (3.9) | 270 (5.6) |
| Pediatrics | 81 (7.2) | 75 (7) | 190 (3.1) | 108 (2.2) |
| Obs & gynae | 40 (3.6) | 51 (4.8) | 174 (2.9) | 221 (4.5) |
| Uro surgery | 25 (2.2) | 23 (2.1) | 132 (2.1) | 100 (2.1) |
| Vascular surgery | 18 (1.6) | 28 (2.6) | 112 (1.8) | 134 (2.8) |
| Orthopedics | 23 (2) | 34 (3.2) | 104 (1.7) | 143 (2.9) |
| Reconstructive surgery | 16 (1.4) | 16 (1.5) | 98 (1.6) | 75 (1.5) |
| Total | 1122 | 1061 | 6072 | 4858 |
The most common indications for FFP usage were acute surgical blood loss, followed by deranged INR with no bleeding and bleeding irrespective of INR in the initial audit. However, in the reaudit, while surgical bleeding remained the prime indication, the number of demands for deranged INR without bleeding reduced considerably by 41.7% [Table 4].
Table 4.
Comparison between FFP utilization as per indications before and after an educational intervention.
| Indications for FFP | Number of FFP before educational campaign (Nov 17 -Nov 18) | Number of FFP after educational campaign (Jan 19 -Dec 19) | Number of patients before educational campaign (Nov 17 -Nov 18) | Number of patients after educational campaign (Jan 19 -Dec 19) |
|---|---|---|---|---|
| Bleeding irrespective of INR (Therapeutic) | 907 | 614 | 168 | 133 |
| Deranged coagulation profile (Prophylactic) | 956 | 557 | 180 | 160 |
| SEPSIS/DIC (Therapeutic) | 680 | 290 | 123 | 73 |
| Massive transfusion/trauma induced coagulopathy (Therapeutic) | 135 | 0 | 23 | 0 |
| Plasmapheresis (Therapeutic) | 560 | 214 | 101 | 19 |
| Liver failure with bleeding irrespective of INR (Therapeutic) | 348 | 393 | 67 | 92 |
| Liver failure without bleeding abnormal INR (Prophylactic) | 302 | 126 | 56 | 28 |
| Volume expansion (Prophylactic) | 64 | 0 | 11 | 0 |
| Hypoproteinemia (Prophylactic) | 258 | 0 | 45 | 0 |
| Surgical blood loss (Mixed) | 1746 | 1812 | 325 | 370 |
| Before invasive procedures (Prophylactic) | 116 | 852 | 23 | 186 |
The initial audit found 51.8% of FFP transfusions to be inappropriate (3069 of 5922, 150 excluded due to incomplete requisition form). The usage of FFP was categorized as appropriate if it was transfused as per the BCSH/CAP guidelines. The reaudit showed a 20% decrease in the overall FFP transfusions over a period of one year. Paired T-test showed a statistically significant reduction in FFP utilization (p = 0.003), as well as in the number of patients transfused (p = 0.003) before and after an educational intervention.
The number of inappropriate transfusions after the educational interventions were 29.5%; hence a 22.3% reduction was seen from the initial audit [Table 5]. Paired T-test between appropriate and inappropriate FFP transfusion before and after educational intervention showed an increased appropriate usage of FFP (p-value 0.001) and a significant reduction in inappropriate usage (p-value 0.003). On correlating the educational intervention with appropriate and inappropriate FFP usage,we found a strong correlation, r value > 0.7.
Table 5.
Comparison between FFP utilization as per appropriateness before and after an educational intervention.
| Specialty | No of FFP appropriate transfusion before educational campaign (Nov 17 -Nov 18) | No of FFP appropriate transfusion after educational campaign (Jan 19 -Dec 19) | No of FFP inappropriate transfusion before educational campaign (Nov 17 -Nov 18) | No of FFP inappropriate transfusion after educational campaign (Jan 19 -Dec 19) |
|---|---|---|---|---|
| General medicine | 674 | 764 | 658 | 209 |
| Medical oncology & oncosurgery | 555 | 450 | 404 | 341 |
| General surgery | 321 | 288 | 234 | 132 |
| Nephrology | 254 | 146 | 268 | 50 |
| Clinical hematology | 210 | 180 | 34 | 90 |
| Neuro surgery | 191 | 223 | 150 | 125 |
| GI surgery | 138 | 168 | 210 | 95 |
| CTVS | 136 | 637 | 732 | 179 |
| Pediatrics | 134 | 58 | 56 | 50 |
| Obstetrics and gynaecology | 96 | 170 | 78 | 51 |
| Urosurgery | 60 | 82 | 62 | 18 |
| Orthopedics | 46 | 104 | 48 | 39 |
| Vascular surgery | 22 | 104 | 66 | 30 |
| Reconstructive surgery | 16 | 49 | 69 | 26 |
| No indication mentioned | 0 | 0 | 150 | 0 |
| Total | 2853 | 3423 | 3219 | 1435 |
Acute DIC with high INR was the most common indication for appropriate FFP transfusion, while the use of FFP for mild derangement of coagulation profile (<1.5 times of normal), hypoproteinemia/hypoalbuminemia and volume expansion were the most frequent causes of inappropriate FFP usage in the initial audit. Prophylactic FFP transfusions prior to invasive procedures remained the most common cause of inappropriate transfusions in the reaudit.
In the initial audit, it was also seen that 48.9% of the total FFP transfusions were therapeutic as compared to 56.7%, which were prophylactic transfusions. This data reversed in the reaudit (51.3% therapeutic and 48.6%prophylactic). The most common indication of prophylactic transfusion was a deranged coagulation profile with no bleeding, whereas most therapeutic transfusions occurred in the settings of surgical blood loss and DIC associated with acute bleeding [Table 4].
Discussion
The use of FFP has steadily increased over the last two decades, but contrary to the principles of “Evidence-based Medicine,” it has become one of the most inappropriately used blood component. Numerous studies on patient blood management and hemovigilance have linked FFP with serious hazards of transfusion like TRALI, TACO, Transfusion-related immunomodulation (TRIM), TTI, anaphylaxis, and even death.12,13 However, most common but less serious hazard of FFP transfusion is the allergic reaction to plasma proteins. Unwarranted use also divests the blood transfusion services of FFP as the spare plasma can be used for plasma fractionation, helping in the availability of cheaper plasma products and aiding the economy of developing nations like ours.7
In this audit, we studied inappropriate FFP transfusions (3069) as a percentage of the total FFP transfusions (5922), which was 51.8% in the initial audit and decreased significantly to 29.5% in the reaudit (1435 out of 4858 FFP transfusions). Previous audits have reflected inappropriate FFP usage ranging from 45.2% to 75%.8, 9, 10, 11 Decrease in inappropriate FFP requests after educational interventions varied from 22% to 35% in various studies, which corroborates with our study. (22–26) However, Yeh et al. reported that the decrease after educational intervention was only 5.2%, which dropped to 30% after computerised transfusion guidelines were implemented. We elaborated the justified indications for the demand of various components on the TDF to achieve a lasting impact of the educational interventions.
Results were further analyzed for specialty wise usage, therapeutic versus prophylactic usage, and the indications/trigger for FFP transfusion.
The highest number of inappropriate transfusions occurred in CTVS (23.8%). While the exact figures differ, inappropriate transfusion episodes in cardiac surgery patients varied from 22.3% to 27.9%, as reported by Prinjaa et al. and Bhagwat et al., respectively.8,10 Commonest surgeries where FFP was transfused were coronary artery bypass grafting (CABG) and cardiac valve replacement. FFP was used mainly to mitigate the probability of bleeding even in the absence of abnormal coagulation tests or reversing the effect of heparin during recovery from bypass surgery. However, no evidence to support this measure was found in the available literature and Cochrane review articles on prophylactic FFP transfusion in cardiac surgery. 20157,14,15
Few randomized control trials (RCT) and many review articles were found after extensive research on PubMed, ResearchGate, and Medline on comparison of therapeutic versus prophylactic usage of FFP.6,14, 15, 16, 17 Arguably, the strongest RCT evidence indicates that prophylactic plasma for transfusion is not effective across a range of different clinical settings. This is also supported by data from nonrandomized studies in patients with mild to moderate abnormalities in coagulation tests. We identified that more than 50% of the transfusions in our setup were prophylactic based on abnormal coagulation test results, mainly in cases of invasive procedures, warfarin toxicity with mild derangement of INR, burns, neonatal sepsis, etc. However, all prophylactic transfusions were not inappropriate, as seen in clinical settings of liver failure, DIC, and surgeries with gross abnormality in coagulation tests, which fulfilled the absolute indications in accordance with BCSH/CAP guidelines.
The most common trigger for inappropriate FFP transfusion in our study was prolonged PT/INR. The threshold for FFP transfusion based on PT/INR and aPTT prolongation of >1–1.5 times normal was based on some old retrospective audits. In reality, prolongation of coagulation tests is not of much significance in perioperative settings.17According to BCSH guidelines, coagulation tests are not mandatory for patients with negative family and personal history of bleeding, however in patients undergoing procedures with a moderate or high risk of bleeding or taking anticoagulants these tests should be performed.6 As per literature, patients with a high pretransfusion INR are more likely to be benefited from FFP transfusion. Moderately raised INR, however, does not show a linear correlation with FFP transfusion.17
INR and aPTT tests are poor predictors of hemorrhage, mainly due to the following aspects:9,17, 18, 19
-
a)
Nonlinear relationship between result and level of coagulation factors.
-
b)
Mildly abnormal test results occur among patients with biologically normal coagulation.
-
c)
The test overestimates the deficiencies in the upper limb of the coagulation cascade and underestimates deficiencies in the lower limb as it chiefly measures Factor VII deficiency.
-
d)
The tests overestimate the extent of coagulation factor depletion if more than one factor is reduced.
-
e)
The INR and aPTT were never designed to predict bleeding but were designed to analyze one aspect of hemostasis i.e. fibrin formation.
Guidelines proposed for FFP usage by BCSH and CAP are expert consensus and recommendations, but their implementation on clinical grounds is minimal, as they are not specialty-based and are not intended to replace the clinical judgment of the attending physicians. Lack of stringent transfusion guidelines, their awareness, and suboptimally functional hospital transfusion committee (HTC) for component usage have been reported to be the most common reasons for inappropriate FFP transfusions in previous studies.20, 21, 22 We need educational interventions in the form of regular CMEs for all stakeholders of blood component therapy, including surgeons, physicians, anesthesiologists, and nursing staff, discussions in HTC, and periodic prospective audits for optimal usage of blood components. Reduction in inappropriate FFP usage ranging from 5.2% to 26.6% has been reported after educational intervention in previous studies.23, 24, 25 HTC plays a crucial role in ensuring economic and safe usage of blood and its components. A functional HTC can invigorate the blood transfusion services through the implementation of national and local guidelines by means of regular audits, training, and standardization of transfusion practices.22,24 It should be actively involved in guiding clinicians about clear indications/contraindications of blood components, preferably on the institutional intranet that can be made interactive. It should ensure that the blood component demand form justifies the requests, documents the important investigations done recently and mentions previous transfusion history.
Another intervention to ensure optimal use of FFP is the use of point-of-care techniques, including viscoelastic tests (thromboelastometry/thromboelastography), which reflect in detail the current hemostatic status. It should be made available especially during cardiovascular surgeries, massive transfusion, and for patients of ongoing DIC.17,18
American Association of Blood Banks (AABB) and other available studies have also highlighted the importance of auditing the use of blood products as a reliable tool to uncover not only their inappropriate usage but also to monitor the extent of the compliance with the provided guidelines by regulatory authorities for the use of these products.1,5
The study has highlighted an increased rate of inappropriate and prophylactic FFP transfusions that can be substantially reduced by regular educational interventions and transfusion audits. Implementation of local guidelines, as ascertained by HTC on the appropriate use of blood components, is also recommended for better usage of this valuable commodity.
Disclosure of competing interest
The authors have none to declare.
Acknowledgments
The authors would like to acknowledge the Hospital Transfusion Committee of Command Hospital (Southern Command), Pune for their active support. The authors also thank the clinicians for being receptive to the educational interventions by the Transfusion Medicine department which could make this study worthwhile.
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