Abstract
Introduction: Fresh Frozen Plasma (FFP) is a blood component separated from whole blood and frozen below -30°C within 8 hours of donation for optimum preservation of coagulation factors. However, logistic and geographical reasons may hamper separation of plasma within 8 hours and the separation may have to be delayed to between 8 and 24 hours and then frozen below -30°C which is called as Frozen Plasma (FP). Plasma separated between 8 and 24 hours is a licensed blood component in the United States of America (USA) for therapeutic use similar to FFP. It is not licensed in India leading to frequent shortage of plasma.
Aim: To compare the activity of factors V, VIII and X and the level of fibrinogen between FFP and FP, so as to assess the therapeutic use of FP for formulating recommendation as licensed blood component.
Materials and Methods: A prospective observational study was conducted in the Department of Transfusion Medicine at Seth GS Medical College and KEM Hospital, Mumbai, Maharashtra, India. The duration of the study was 10 months, from January 2018 to October 2018. Fifty units each of FFP and FP matched for the camp location, age, gender and blood group were selected. There were 44 males and six females in each of FFP and FP groups. They were compared for the activity of labile coagulation factors (factors V and VIII) and stable factor X. The level of fibrinogen was also measured in both components. It was done within 30 days of preparation of plasma. The mean values of each of the four parameters for FFP and FP were calculated and compared for statistical significance (p) by using unpaired Student’s t-test. Microsoft Excel 2016 was used for statistical analysis. The p-value <0.05 was considered statistically significant.
Results: The mean age of FFP and FP individuals (blood donors) was 31.2 and 31.3 years respectively, while the median age in years was 31 and 30.5, respectively. The activity/level of all the tested coagulation factors was lower in FP as compared to FFP. The difference was statistically significant for factor VIII (p-value <0.05). It was not significant for factor V, X and fibrinogen. The level/activity of coagulation factors in FP, though lower than that in FFP, fell within normal reference range in 90- 95% of units.
Conclusion: FP may be used as a therapeutic alternative to FFP excluding patients of haemophilia A in whom factor VIII concentrate and cryoprecipitate are considered better therapeutic modalities. Results of similar multicentre studies will help in formulating recommendations regarding licensing.
Introduction
The FFP is a blood component that is frozen below -30°C within a short specified period after collection (usually 8 hours) [1]. It contains plasma proteins and all the coagulation factors, including the labile factors V and VIII [2]. The use of FFP is indicated in patients with single coagulation factor deficiencies where the appropriate concentrate is not available (for example: factors V, XI), acute disseminated intravascular coagulation, plasma exchange for thrombotic thrombocytopenic purpura (TTP), and in some instances of liver disease, warfarin reversal, cardiopulmonary bypass, and massive transfusion [3]. When FFP is frozen within 8 hours of its preparation at below -30°C, levels of coagulation factors like V, VIII, II, IX, X, XI, and fibrinogen remain stable with good relevant activity [1,4]. Factors V and VIII are known labile factors, whereas, fibrinogen is a stable factor. Factor VIII level is also one of the quality control parameters for FFP as per the guidelines by Directorate General of Health Services (DGHS), India [5]. According to these guidelines, 75% of the units of FFP should have factor VIII levels greater than 0.7 IU/mL. To meet this requirement, plasma is usually separated from whole blood and frozen within 8 hours of collection [6,7].
These requirements for FFP preparation limit the number of units of whole blood that can be processed into FFP in large blood centres that collect and transport blood over a wide geographic area. In a few situations, it is not possible to separate the whole blood and/or freeze the separated plasma within 8 hours of collection due to logistic and administrative reasons [8-10]. These limitations result in not infrequent shortages of FFP [8]. Extension of the allowable processing time for plasma for transfusion i.e., FFP to 24 hours after collection of whole blood would alleviate this problem. This plasma that is frozen at later intervals (usually up to 24 hours) after collection has been referred to as plasma frozen within 24 hours after phlebotomy (PF24) [1]. There have been growing global interest and efforts invested in exploring the efficacy and benefits of using PF24 for transfusion purpose. PF24 is a licensed blood component in the USA [11,12]. Since, it is not yet licensed in India, it cannot be used for therapeutic purposes for indications similar to FFP.
A number of studies have been performed to investigate the effect of extended storage of blood prior to plasma separation, especially on coagulation factors [6,8,10,13-19]. Only one out of these studies is from India, which was conducted in a Northern Indian state [13]. Considering this background, the authors undertook this prospective observational study with the overall goal to determine whether separation of plasma after 8 hours of blood collection has any effect on the level of coagulation factors. To achieve this goal, the activity of labile coagulation factors (V and VIII), factor X and level of fibrinogen in FFP were compared with those in the plasma units that were separated and frozen after 8 hours of collection but before 24 hours of blood collection (FP).
Materials and methods
A prospective observational study was conducted in the Department of Transfusion Medicine at Seth GS Medical College and KEM Hospital, Mumbai, Maharashtra, India. The duration of the study was 10 months, from January 2018 to October 2018. The blood centre collects on an average 2000 blood units per month indoor, as well as, from outdoor blood donation camps. Ethical approval was granted by the Institutional Ethics Committee as per approval letter no. IEC/116/2016 and continuation permission letter IEC (I)/ OUT/1907 dated 28/8/2017.
Detection of Renal Abnormalities
- Proteinuria: A pivotal indicator of renal abnormalities is the presence of abnormal protein levels in urine, known as proteinuria. Urinalysis analyzers play a crucial role in identifying proteinuria by accurately measuring protein concentration. Elevated levels may suggest kidney damage, glomerular disorders, or other renal issues, necessitating further investigation.
- Hematuria: The presence of blood in urine, termed hematuria, can indicate various renal conditions such as kidney stones, infections, or more serious issues like glomerulonephritis or tumors. Urinalysis analyzers assist in detecting hematuria by identifying red blood cells in urine sediment.
- Glucose and Ketones: Abnormal levels of glucose and ketones in urine may signal diabetic nephropathy or other metabolic disorders affecting the kidneys. Urinalysis analyzers provide a swift and accurate assessment of these parameters, aiding in the early detection and management of renal complications associated with diabetes.
- Crystals and Casts: Microscopic examination of urine sediment using urinalysis analyzers allows for the detection of crystals and casts. Crystals may indicate conditions such as kidney stones, while the presence of casts, formed in the renal tubules, can suggest various renal diseases, including acute or chronic nephritis.
- pH and Specific Gravity: The measurement of urine pH and specific gravity offers valuable information about concentration and acid-base balance within the body. Deviations from the normal range may indicate renal tubular acidosis, dehydration, or other renal function abnormalities.
Benefits of Urinalysis Analyzers
Sample size calculation
The study was performed on plasma samples obtained from the segments of plasma units. It was performed on 50 units each of FFP and plasma separated after 8 hours (FP). The sample size calculation was based on the level of significance (p-value=0.05), the desired margin of error and standard deviation [20].
The following formula was used: n=(for ZϬd/E)2
where Z=confidence level=1.96 for 95%. Ϭd=standard deviation=71.2% for factor VIII level in FFP as obtained from one year quality control data of factor VIII on FFP at tertiary blood centre. The authors considered standard deviation of factor VIII in calculation as it is a heat labile coagulation factor and a quality control parameter for FFP. E=desired margin of error=20% as considered for the present study.
N=(1.96×71.2/20)2=48.6850 units each of FFP and FP
Inclusion criteria: Samples from plasma units separated between 8 and 24 hours and those separated within 8 hours of collection matched for age, gender and ABO blood group were included in the study.
Exclusion criteria: Study samples which showed visible lipemia and/or which were reactive for any of the Transfusion-Transmissible Infections (TTIs) (i.e., HIV, hepatitis C, hepatitis B, malaria, syphilis) were excluded from the study.
