Serial assessment of biochemical parameters of red cell preparations to evaluate safety for neonatal transfusions.

Background & Objectives: Neonatologists often prefer fresh blood (<7 days) for neonatal transfusions. The main concerns for stored RBCs are ex vivo storage lesions that undermine red cell functions and may affect metabolic status of neonatal recipients. This study was designed to evaluate serial in vitro changes of biochemical parameters in different RBC preparations during storage to consider for neonatal transfusions even after storage beyond one week. Methods: Twenty five units each of whole blood (CPDA-1 RBC, SAGM RBC) were selected for serial biochemical parameter assessment after each fulfilled the quality criteria (volume and haematocrit). These units were tested serially for supernatant potassium, pH, lactate, haemoglobin, glucose and red cell 2,3 diphosphoglycerate (2,3 DPG) up to 21 days of storage. Results: Within each group of RBC, rise in mean concentration of potassium, lactate and plasma haemoglobin from day 1 to 21 of storage was significant in CPDA-1 RBC having the highest levels at day 21. From day 3 to 21, SAGM RBC had higher mean pH value than CPDA-1 RBC though this difference was not statistically significant. SAGM RBC had highest mean glucose concentration during storage than other two types of red cell preparations (P<0.005). Within each group, fall in mean 2,3 DPG concentration from day 1 to 7 was significant (P<0.05). A positive correlation existed between mean plasma potassium and haemoglobin in all three types of red cells (r=0.726, 0.419, 0.605 for CPDA-1 RBC, SAGM RBC and whole blood respectively, P<0.005). Interpretation & Conclusions: All the three red cell preparations tested revealed biochemical changes within acceptable limits of safety till 21 days of storage. CPDA-1 RBCs had the highest degree of these changes.

Transfusion related acute lung injury.

Transfusion related acute lung injury (TRALI) is an uncommon but potentially fatal adverse reaction to transfusion of plasma containing blood components. We describe a case of 10-year-old male child with aplastic anemia, platelet count of 7800/΅l, B positive blood group who developed fever (39.2΀C), difficulty in breathing and cyanosis within 2 hrs after transfusion of a random platelet concentrate. Despite the best resuscitative efforts, the child died within next 24 hrs. The present case highlights the fact that TRALI should be kept as a differential diagnosis in all patients developing acute respiratory discomfort within 6 hrs of transfusion. Without a 'gold standard' the diagnosis of TRALI relies on a high index of suspicion and on excluding other types of transfusion reactions. Notification to transfusion services is crucial to ensure that a proper investigation is carried out and at-risk donor and recipients can be identified, and risk reduction measures can be adopted.

Feasibility of pre-operative autologous blood donation in Indian patients with elective orthopaedic surgery.

BACKGROUND & OBJECTIVES: Pre-operative autologous blood donation (PABD) in elective orthopaedic surgeries is a well known procedure in the West. We initiated this programme at a tertiary care hospital in north India to study its feasibility in Indian patients. METHODS: In a prospective case-control study, 144 patients undergoing primary total hip or knee replacement, inter-vertebral discectomy, mal-union and non-union reconstruction were educated and motivated to pre-donate. Patients fulfilling the inclusion criteria and making autologous donation formed the PABD group (n=22). Patients eligible for PABD, but unwilling to participate; age, sex, pre-operative haemoglobin and operative procedure matched acted as controls (n=27). Unit(s) collected was processed like an allogeneic unit. Unit(s) found reactive for infectious markers or not utilized was discarded. Mean blood losses, transfusion trigger, allogeneic exposure and wastage between the two groups were compared. RESULTS: Of the 144 patients motivated, 40 per cent of the eligible subjects pre-deposited. The main motivational factor was fear of getting infection from someone's blood. Cardiac events and anaemia prevented 61.8 per cent patients to participate. Of the 50 units ordered, autologous units with a mean of 1.4 units/patient contributed 62 per cent. For total hip and total knee replacement (THR and TKR), autologous units met 76.2 and 80 per cent respectively of the total blood requirement. A significant decrease in the allogeneic exposure was observed between PABD and control group (18.2 vs 66.7%); 32.3 per cent of the autologous units were discarded. INTERPRETATION & CONCLUSION: Comprehensive PABD programme may be an effective method for reducing the need for allogeneic transfusion in patients undergoing joint replacement surgeries in our country, where transfusion transmitted infections due to high percentage of replacement donations and lack of sensitive assays for testing are still a cause for concern.

Prevalence & significance of hepatitis C virus (HCV) seropositivity in blood donors.

BACKGROUND & OBJECTIVES: The clinical significance of anti HCV antibodies in healthy blood donors remains uncertain. These donors are usually asymptomatic and it is difficult to elicit risk factors of acquiring HCV infection during pre-donation questioning. Limited information on donor recall and follow up studies on anti HCV positive blood donors have been reported from India. Paucity of data which is likely to have an impact on safe blood transfusion programme has prompted us to undertake this study to assess the significance of HCV seropositivity in blood donors with respect to their clinical, biochemical and virological profile. METHODS: A total of 16,250 blood units were screened for the mandatory tests using third generation ELISA (anti HIV 1&2, anti HCV, HBsAg), VDRL and peripheral smear for malaria. Donors reactive for anti HCV were informed. Repeat anti HCV reactive donors were subjected to detailed clinical history focusing on risk factors for HCV transmission. The blood tests included liver function tests (LFT), coagulation and autoimmune profile, qualitative serum cryoglobulins and HCV RNA detection. These donors were followed at 2-3 monthly intervals for a minimum period of six months by LFT. RESULTS: An overall seropositivity of 0.44 per cent (72/16,250) was observed in our donors which was significantly lower in first time, young voluntary donors as compared to replacement donors (0.27 vs. 0.60%). In contrast to drug abuse (6.4%) we found minor percutaneous routes like sharing of shaving kits or visit to a road side barber (32%) as the major risk factor for HCV transmission. There was no prior history of blood transfusion in any of these donors; however history of some surgical procedures was present in 25.8 per cent. Raised transaminases and HCV viraemia were observed in 87 and 71 per cent donors respectively. An association was observed between HCV RNA when the ELISA ratio was >5. INTERPRETATION & CONCLUSION: Voluntary donors form a safe source of blood supply and efforts should be made to increase this precious source to 100 per cent. Abbreviated behavioural donor screening questionnaire for repeat donors is not advisable. Awareness and education of donors is required regarding modes of HCV transmission. HCV positive donors should be informed about their disease, counselled and referred to hepatologist, and permanently deferred for future donations.

Anti Kell allo-antibody in a thalassaemic.

We describe a case of incidental detection of anti Kell antibody in a child with transfusion dependent thalassaemia. Kell antibody detection may be missed by routine indirect antiglobulin test (IAT) crossmatch procedure because of low prevalence of Kell antigen in the general population. A false negative result can be avoided by using sensitive cross matching techniques and screening cells representing antigens in homozygous state, against all clinically significant antibodies. A transfusion alert card describing the nature of antibody and future transfusion policy should be given to such allo-immunized patients.