http://informahealthcare.com/jmf ISSN: 1476-7058 (print), 1476-4954 (electronic) J Matern Fetal Neonatal Med, Early Online: 1–3 ! 2014 Informa UK Ltd. DOI: 10.3109/14767058.2013.879708
ORIGINAL ARTICLE
The impact of evaluating platelet transfusion need by platelet mass index on reducing the unnecessary transfusions in newborns J Matern Fetal Neonatal Med Downloaded from informahealthcare.com by University of Maastricht on 06/21/14 For personal use only.
Dilek Kahvecioglu, Omer Erdeve, Serdar Alan, Ufuk Cakir, Duran Yildiz, Begum Atasay, and Saadet Arsan Department of Pediatrics, Division of Neonatology, School of Medicine, Ankara University, Ankara, Turkey
Abstract
Keywords
Introduction: Almost 95% of the platelet transfusions (PTs) conducted in the neonatal intensive care unit (NICU) are prophylactic transfusions. Guidelines for prophylactic PTs are based on platelet counts, but not on platelet functions. Nowadays, in order to reduce unnecessary transfusions, utilizing platelet mass index (PMI) was investigated. The aim of study is to find out whether PTs performed in our NICU during last 2 years were in accordance with the current guideline and to evaluate whether the frequency of PTs should be reduced if PMI was considered. Methods: Forty-three infants who received 96 prophylactic PTs were enrolled in the study. The guideline utilized in our NICU advocate keeping the platelet count: (a) 4100 000 in pre/ post-operative, (b) 450 000 in unstable and (c) 420 000 in stable patients. According to PMI criteria, PT should be performed if PMI: (a) 5800 in pre/post-operative, (b)5400 in unstable and (c) 5160 in stable patients. Results: In all, 53.2% of PTs should not be given if the decision was in accordance with the current guideline. If decision for every PT was made according to the current guideline and taking PMI into consideration, an additional 11.5% reduction in total PTs could be achived. Conclusion: We suggest that better compliance with the new guidelines which take platelet functions into account may yield lower transfusion rate, lower costs and better conservation of blood bank resources.
Neonate, platelet mass, platelet transfusions
Introduction The definition of thrombocytopenia is a platelet count 5150 000 among patients of all ages [1]. Totally 22–35% of infants admitted to the neonatal intensive care unit (NICU) are affected by thrombocytopenia at their hospital stay [2,3]. Almost 95% of the platelet transfusions (PTs) conducted in the NICU are prophylactic transfusions that are performed to reduce the risk of spontaneous bleeding [1,2]. Timing of PTs to decrease an infant’s presumed risk for hemorrhage is usually a difficult task [2,4]. Guidelines for prophylactic PTs are based on platelet counts and the condition of the neonate, but not on platelet functions. Nowadays, in order to reduce unnecessary transfusions, utilizing platelet mass index (PMI ¼ mean platelet volume platelet count/1000) is investigated [1]. PMI is related to the platelet functionality; larger platelets function better to form an effective platelet plug. On the other hand, PTs are associated with the risks of transmission of bacterial and viral infections, fever, hemolytic and allergic reactions [4]. Identifying and eliminating unnecessary PTs by adopting Address for correspondence: Dilek Kahveciog˘lu, MD, Department of Pediatrics, Division of Neonatology, School of Medicine, Ankara University, Ankara 06260, Turkey. Tel: +90505 9487940. Fax: +0 312 236 21 01. E-mail: [email protected]
History Received 25 November 2013 Revised 19 December 2013 Accepted 29 December 2013 Published online 3 February 2014
specific guidelines would therefore reduce both the risks and costs of this procedure. There is only one study in the literature which evaluated PMI as a guideline criteria for neonatal PTs [5]. The aim of the present study was to find out whether PTs performed during last 2 years were in accordance with the current guidelines in our NICU, and to evaluate whether the frequency of PTs should be reduced if PMI was considered.
Methods In this retrospective study, data were collected from patient records of newborns who were admitted to the NICU at Ankara University Hospital, Ankara, Turkey and survived 424 h. Forty-three infants who received 96 prophylactic PTs between January 2011 and March 2013 were enrolled in the study. All transfusions were random-donor PTs, neither pooled, nor volume reduced and administered in a volume of 10 ml per kg of body weight. Transfusions due to active bleeding were excluded. The guideline utilized in our NICU at that time advocate keeping the platelet count: (a) 4100 000 106/L in pre/postoperative patients, (b) 450 000 106/L in unstable patients (on invasive mechanical ventilation or circulatory support and patients with sepsis) and (c) 420 000 106/L in stable patients.
J Matern Fetal Neonatal Med Downloaded from informahealthcare.com by University of Maastricht on 06/21/14 For personal use only.
2
D. Kahvecioglu et al.
J Matern Fetal Neonatal Med, Early Online: 1–3
According to PMI criteria, PT should be performed if PMI: (a) 5800 in pre/post-operative patients, (b) 5400 in unstable patients and (c) 5160 in stable patients [1]. All PTs were evaluated according to their compliance to the present guideline, and the indications were compared in relation to PMI criteria to find out the unnecassary PTs rate. Data analyses were performed using Statistical Package for Social Sciences (SPSS), version 15.0 (SPSS, Inc., Chicago, IL). Descriptive statistics for variables with a normal distribution, mean (±standard deviation), for nonnormally distributed variables median (minumum–maximum) were used. Nominal variables were showed with the number of cases and percentage (%). The significant differences between group means were analyzed with t-test and medians with Mann–Whitney test. Nominal variables were evaluated with Pearson’s Chi-square or Fisher’s exact test. For investigating the relationship between continuous variables, Pearson correlation test was used for normal distribution and Spearman’s correlation test was used when the distribution was not normal. p Value of 50.05 was considered statistically significant.
Results A total of 96 PTs were performed in 43 patients during the study period. Table 1 shows the demographic and clinical characteristics of the patients. We found poor correlation between the number of PTs and birth weight (r 0.311, p50.042), gestational age (r 0.347, p50.023), mechanical ventilation (r 0.452, p50.002) and duration of hospitalization (r 0.479, p50.001). There was no correlation between the number of PTs and mortality (p ¼ 0.1). PT decisions were usually made by the attending neonatologist and 53.2% (n ¼ 51) would have not be performed if the decision was in accordance with the current NICU guideline. Five PTs of the stable patients would not be given, only if the attending neonatologist was in compliance with the current NICU guideline. The group consisted pre/post-operative patients, in which compliance with the guideline was mostly achieved (80%) (Table 2). Table 1. The demographic and clinical characteristics of the patients. Gestational age (week) (median) Birth weight (g) (median) Gender (male/female) Number of transfusion per patient (median) Days of hospital stay Mortality (%)
30 (23–41) 1000 (400–4050) 26/17 2 (1–8) 19 (1–74) 48.8
Table 2. Transfusions in aaccordance with the current guideline in last 2 years. Condition of the patient Pre/post-operative Unstable Stable Total
Number of transfusions (n) 5 86 5 96
Compliance with guideline (%) 80 48.8 0 46.8
(n ¼ 3) (n ¼ 42) (n ¼ 0) (n ¼ 45)
If decision for every PT was made according to the current NICU guideline and taking PMI into consideration, an additional 11.5% (n ¼ 11) reduction in total PTs could be achived. In total, it was observed that 62 (64.5%) PTs could be avoided: 11 in case of PMI criteria use and 51 in case of strict compliance to the guideline.
Discussion Most neonatal PTs are prophylactic, meaning that they are given to neonates with thrombocytopenia who have no signs of bleeding. A decision to order a prophylactic PT in the NICU is based on the platelet count and the condition of the neonate. However, the risk of spontaneous bleeding is influenced by many factors, such as platelet function, coagulation disorders of neonate and presence of inflammation or infection. Stanworth et al. [6] who enrolled 194 infants with platelets520 000/mL in their study found that 91% of the patients did not develop any major hemorrhage. Muthukumar et al. [7] also found that gestational age at 534 weeks, development of severe thrombocytopenia within 10 d of birth and necrotizing enterocolitis were the strongest predictors for an increased number of bleeding events. For neonates with severe thrombocytopenia, a lower platelet count was not a strong predictor of increased bleeding. Therefore, new guidelines which take platelet functions into account instead of only platelet count may have advantages to reduce prophylactic PTs [5]. Adherence to transfusion guidelines in the NICU has not been well studied. Peta¨ja¨ et al. [8] enrolled 543 patients and found that 32% of PTs were given with a platelet count 450 000/mL and 60% of transfusions were not given in accordance with their current guidelines. Baer et al. reviewed two studies about compliance with the guidelines and they reported that their compliance was 52% in 2007 among 1600 thrombocytopenic infants who recieved 494 transfusions and 65% among 70 infants who received PTs in 2008 [9,10]. After these studies they implemented a program to improve the compliance and they achived to increase the compliance upto 90% which resulted in 174 fewer PTs [11]. The compliance with our NICU’s guideline in the last 2 years was 46.8% in our study. Although this compliance rate showed similarity with the literature, because our study had a retrospective design, we were not able to determine the reasons of transfusions. We think that the main cause of non-compliance to the guideline seems to be the clinicians’ interpretation of patient’ as more severe than it actually was. Assuming normal function of platelet and endothelium, the hemostatic efficacy of platelet plug formation may be influenced more by the platalet mass than by platelet count because larger platelets function better to form an effective platelet plug. PMI is a new concept which was defined to use platelet function in decision of PTs in the NICU. It was first evaluated by Gerday et al. who reported that using platelet mass reduced the number of PTs [5]. This report was a prospective study which compared the platelet count guideline versus platelet mass guideline. The transfusion rate was decreased from 3.6% to 1.9% by using platelet mass guideline without any increase in bleeding complications. Our study demonstrated that a significant additional reduction (n ¼ 11)
J Matern Fetal Neonatal Med Downloaded from informahealthcare.com by University of Maastricht on 06/21/14 For personal use only.
DOI: 10.3109/14767058.2013.879708
in PTs could be achieved by using PMI in addition to the current NICU guideline. Baer et al. also found that the number of PTs predicts the mortality rate in the NICU [9]. They suggested that it might be due to increased levels of platelet activating factor which exacerbates inflammatory injury, transfusion of bacterial infection, multiple donor exposure and unknown some other factors. Therefore, unnecessary PTs should be avoided to prevent neonatal complications and mortality. In our study we could not find any relationship between the number of transfusions and mortality (p ¼ 0.1), but overall mortality was very high (48.8%). Probably PTs were administered mostly to unstable patients in our study group. In conclusion, our study demonstrated that compliance to the guidelines was low. On the other hand, there is a need for better guidelines to decrease unnecessary PTs. We suggest that better compliance with the new guidelines which take platelet functions into account may yield lower transfusion rate, lower costs and better conservation of blood bank resources.
Evaluating platelet transfusion need by platelet mass index
3.
4.
5.
6.
7.
8.
9.
Declaration of interest The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.
10.
References
11.
1. Christensen RD. Platelet transfusion in the neonata intensive care unit: benefits, risks, alternatives. Neonatology 2011;100:311–18. 2. Von Lindern JS, van den Bruele T, Lopriore E, Walther FJ. Thrombocytopenia in neonates and the risk of intraventricular
3
hemorrhage: a retrospective cohort study. BMC Pediatr 2011;11: 11–16. Del Vecchio A, Motta M, Radicioni M, Christensen RD. A consistent approach to platelet transfusion in the NICU. J Matern Fetal Neonatal Med 2012;25:93–6. Borges JP, dos Santos AM, da Cunha DH, et al. Restrictive guideline reduces platelet count thresholds for transfusions in very low birth weight preterm infants. VoxSang 2013;104:207–13. Gerday E, Baer VL, Lambert DK, et al. Testing platelet mass versus platelet count to guide platelet transfusions in the neonatal intensive care unit. Transfusion 2009;49:2034–9. Stanworth SJ, Clarke P, Watts T, et al. Platelets and neonatal transfusion study group, prospective, observational study of outcomes in neonates with severe thrombocytopenia. Pediatrics 2009;124:826–34. Muthukumar P, Venkatesh V, Curley A, et al.; Platelets Neonatal Transfusion Study Group. Severe thrombocytopenia and patterns of bleeding in neonates: results from a prospective observational study and implications for use of platelet transfusions. Transfus Med 2012;22:338–43. Peta¨ja¨ J, Andersson S, Syrja¨la¨ M. A simple automatized audit system for following and managing practices of platelet and plasma transfusions in a neonatal intensive care unit. Transfus Med 2004; 14:281–8. Baer VL, Lambert DK, Henry E, et al. Do platelet transfusions in the NICU adversely affect survival? Analysis of 1600 thrombocytopenic neonates in a multihospital health care system. J Perinatol 2007;27:790–6. Baer VL, Lambert DK, Schmutz N, et al. Adherence to NICU transfusion guidelines: data from a multihospital health care system. J Perinatol 2008;28:492–7. Baer VL, Henry E, Lambert DK, et al. Implementing a program to improve compliance with neonatal intensive care unit transfusion guidelines was accompanied by a reduction in transfusion rate: a pre-post analysis within a multihospital health care system. Transfusion 2011;51:264–9.
ORIGINAL ARTICLE
The impact of evaluating platelet transfusion need by platelet mass index on reducing the unnecessary transfusions in newborns J Matern Fetal Neonatal Med Downloaded from informahealthcare.com by University of Maastricht on 06/21/14 For personal use only.
Dilek Kahvecioglu, Omer Erdeve, Serdar Alan, Ufuk Cakir, Duran Yildiz, Begum Atasay, and Saadet Arsan Department of Pediatrics, Division of Neonatology, School of Medicine, Ankara University, Ankara, Turkey
Abstract
Keywords
Introduction: Almost 95% of the platelet transfusions (PTs) conducted in the neonatal intensive care unit (NICU) are prophylactic transfusions. Guidelines for prophylactic PTs are based on platelet counts, but not on platelet functions. Nowadays, in order to reduce unnecessary transfusions, utilizing platelet mass index (PMI) was investigated. The aim of study is to find out whether PTs performed in our NICU during last 2 years were in accordance with the current guideline and to evaluate whether the frequency of PTs should be reduced if PMI was considered. Methods: Forty-three infants who received 96 prophylactic PTs were enrolled in the study. The guideline utilized in our NICU advocate keeping the platelet count: (a) 4100 000 in pre/ post-operative, (b) 450 000 in unstable and (c) 420 000 in stable patients. According to PMI criteria, PT should be performed if PMI: (a) 5800 in pre/post-operative, (b)5400 in unstable and (c) 5160 in stable patients. Results: In all, 53.2% of PTs should not be given if the decision was in accordance with the current guideline. If decision for every PT was made according to the current guideline and taking PMI into consideration, an additional 11.5% reduction in total PTs could be achived. Conclusion: We suggest that better compliance with the new guidelines which take platelet functions into account may yield lower transfusion rate, lower costs and better conservation of blood bank resources.
Neonate, platelet mass, platelet transfusions
Introduction The definition of thrombocytopenia is a platelet count 5150 000 among patients of all ages [1]. Totally 22–35% of infants admitted to the neonatal intensive care unit (NICU) are affected by thrombocytopenia at their hospital stay [2,3]. Almost 95% of the platelet transfusions (PTs) conducted in the NICU are prophylactic transfusions that are performed to reduce the risk of spontaneous bleeding [1,2]. Timing of PTs to decrease an infant’s presumed risk for hemorrhage is usually a difficult task [2,4]. Guidelines for prophylactic PTs are based on platelet counts and the condition of the neonate, but not on platelet functions. Nowadays, in order to reduce unnecessary transfusions, utilizing platelet mass index (PMI ¼ mean platelet volume platelet count/1000) is investigated [1]. PMI is related to the platelet functionality; larger platelets function better to form an effective platelet plug. On the other hand, PTs are associated with the risks of transmission of bacterial and viral infections, fever, hemolytic and allergic reactions [4]. Identifying and eliminating unnecessary PTs by adopting Address for correspondence: Dilek Kahveciog˘lu, MD, Department of Pediatrics, Division of Neonatology, School of Medicine, Ankara University, Ankara 06260, Turkey. Tel: +90505 9487940. Fax: +0 312 236 21 01. E-mail: [email protected]
History Received 25 November 2013 Revised 19 December 2013 Accepted 29 December 2013 Published online 3 February 2014
specific guidelines would therefore reduce both the risks and costs of this procedure. There is only one study in the literature which evaluated PMI as a guideline criteria for neonatal PTs [5]. The aim of the present study was to find out whether PTs performed during last 2 years were in accordance with the current guidelines in our NICU, and to evaluate whether the frequency of PTs should be reduced if PMI was considered.
Methods In this retrospective study, data were collected from patient records of newborns who were admitted to the NICU at Ankara University Hospital, Ankara, Turkey and survived 424 h. Forty-three infants who received 96 prophylactic PTs between January 2011 and March 2013 were enrolled in the study. All transfusions were random-donor PTs, neither pooled, nor volume reduced and administered in a volume of 10 ml per kg of body weight. Transfusions due to active bleeding were excluded. The guideline utilized in our NICU at that time advocate keeping the platelet count: (a) 4100 000 106/L in pre/postoperative patients, (b) 450 000 106/L in unstable patients (on invasive mechanical ventilation or circulatory support and patients with sepsis) and (c) 420 000 106/L in stable patients.
J Matern Fetal Neonatal Med Downloaded from informahealthcare.com by University of Maastricht on 06/21/14 For personal use only.
2
D. Kahvecioglu et al.
J Matern Fetal Neonatal Med, Early Online: 1–3
According to PMI criteria, PT should be performed if PMI: (a) 5800 in pre/post-operative patients, (b) 5400 in unstable patients and (c) 5160 in stable patients [1]. All PTs were evaluated according to their compliance to the present guideline, and the indications were compared in relation to PMI criteria to find out the unnecassary PTs rate. Data analyses were performed using Statistical Package for Social Sciences (SPSS), version 15.0 (SPSS, Inc., Chicago, IL). Descriptive statistics for variables with a normal distribution, mean (±standard deviation), for nonnormally distributed variables median (minumum–maximum) were used. Nominal variables were showed with the number of cases and percentage (%). The significant differences between group means were analyzed with t-test and medians with Mann–Whitney test. Nominal variables were evaluated with Pearson’s Chi-square or Fisher’s exact test. For investigating the relationship between continuous variables, Pearson correlation test was used for normal distribution and Spearman’s correlation test was used when the distribution was not normal. p Value of 50.05 was considered statistically significant.
Results A total of 96 PTs were performed in 43 patients during the study period. Table 1 shows the demographic and clinical characteristics of the patients. We found poor correlation between the number of PTs and birth weight (r 0.311, p50.042), gestational age (r 0.347, p50.023), mechanical ventilation (r 0.452, p50.002) and duration of hospitalization (r 0.479, p50.001). There was no correlation between the number of PTs and mortality (p ¼ 0.1). PT decisions were usually made by the attending neonatologist and 53.2% (n ¼ 51) would have not be performed if the decision was in accordance with the current NICU guideline. Five PTs of the stable patients would not be given, only if the attending neonatologist was in compliance with the current NICU guideline. The group consisted pre/post-operative patients, in which compliance with the guideline was mostly achieved (80%) (Table 2). Table 1. The demographic and clinical characteristics of the patients. Gestational age (week) (median) Birth weight (g) (median) Gender (male/female) Number of transfusion per patient (median) Days of hospital stay Mortality (%)
30 (23–41) 1000 (400–4050) 26/17 2 (1–8) 19 (1–74) 48.8
Table 2. Transfusions in aaccordance with the current guideline in last 2 years. Condition of the patient Pre/post-operative Unstable Stable Total
Number of transfusions (n) 5 86 5 96
Compliance with guideline (%) 80 48.8 0 46.8
(n ¼ 3) (n ¼ 42) (n ¼ 0) (n ¼ 45)
If decision for every PT was made according to the current NICU guideline and taking PMI into consideration, an additional 11.5% (n ¼ 11) reduction in total PTs could be achived. In total, it was observed that 62 (64.5%) PTs could be avoided: 11 in case of PMI criteria use and 51 in case of strict compliance to the guideline.
Discussion Most neonatal PTs are prophylactic, meaning that they are given to neonates with thrombocytopenia who have no signs of bleeding. A decision to order a prophylactic PT in the NICU is based on the platelet count and the condition of the neonate. However, the risk of spontaneous bleeding is influenced by many factors, such as platelet function, coagulation disorders of neonate and presence of inflammation or infection. Stanworth et al. [6] who enrolled 194 infants with platelets520 000/mL in their study found that 91% of the patients did not develop any major hemorrhage. Muthukumar et al. [7] also found that gestational age at 534 weeks, development of severe thrombocytopenia within 10 d of birth and necrotizing enterocolitis were the strongest predictors for an increased number of bleeding events. For neonates with severe thrombocytopenia, a lower platelet count was not a strong predictor of increased bleeding. Therefore, new guidelines which take platelet functions into account instead of only platelet count may have advantages to reduce prophylactic PTs [5]. Adherence to transfusion guidelines in the NICU has not been well studied. Peta¨ja¨ et al. [8] enrolled 543 patients and found that 32% of PTs were given with a platelet count 450 000/mL and 60% of transfusions were not given in accordance with their current guidelines. Baer et al. reviewed two studies about compliance with the guidelines and they reported that their compliance was 52% in 2007 among 1600 thrombocytopenic infants who recieved 494 transfusions and 65% among 70 infants who received PTs in 2008 [9,10]. After these studies they implemented a program to improve the compliance and they achived to increase the compliance upto 90% which resulted in 174 fewer PTs [11]. The compliance with our NICU’s guideline in the last 2 years was 46.8% in our study. Although this compliance rate showed similarity with the literature, because our study had a retrospective design, we were not able to determine the reasons of transfusions. We think that the main cause of non-compliance to the guideline seems to be the clinicians’ interpretation of patient’ as more severe than it actually was. Assuming normal function of platelet and endothelium, the hemostatic efficacy of platelet plug formation may be influenced more by the platalet mass than by platelet count because larger platelets function better to form an effective platelet plug. PMI is a new concept which was defined to use platelet function in decision of PTs in the NICU. It was first evaluated by Gerday et al. who reported that using platelet mass reduced the number of PTs [5]. This report was a prospective study which compared the platelet count guideline versus platelet mass guideline. The transfusion rate was decreased from 3.6% to 1.9% by using platelet mass guideline without any increase in bleeding complications. Our study demonstrated that a significant additional reduction (n ¼ 11)
J Matern Fetal Neonatal Med Downloaded from informahealthcare.com by University of Maastricht on 06/21/14 For personal use only.
DOI: 10.3109/14767058.2013.879708
in PTs could be achieved by using PMI in addition to the current NICU guideline. Baer et al. also found that the number of PTs predicts the mortality rate in the NICU [9]. They suggested that it might be due to increased levels of platelet activating factor which exacerbates inflammatory injury, transfusion of bacterial infection, multiple donor exposure and unknown some other factors. Therefore, unnecessary PTs should be avoided to prevent neonatal complications and mortality. In our study we could not find any relationship between the number of transfusions and mortality (p ¼ 0.1), but overall mortality was very high (48.8%). Probably PTs were administered mostly to unstable patients in our study group. In conclusion, our study demonstrated that compliance to the guidelines was low. On the other hand, there is a need for better guidelines to decrease unnecessary PTs. We suggest that better compliance with the new guidelines which take platelet functions into account may yield lower transfusion rate, lower costs and better conservation of blood bank resources.
Evaluating platelet transfusion need by platelet mass index
3.
4.
5.
6.
7.
8.
9.
Declaration of interest The authors report no conflicts of interest. The authors alone are responsible for the content and writing of this article.
10.
References
11.
1. Christensen RD. Platelet transfusion in the neonata intensive care unit: benefits, risks, alternatives. Neonatology 2011;100:311–18. 2. Von Lindern JS, van den Bruele T, Lopriore E, Walther FJ. Thrombocytopenia in neonates and the risk of intraventricular
3
hemorrhage: a retrospective cohort study. BMC Pediatr 2011;11: 11–16. Del Vecchio A, Motta M, Radicioni M, Christensen RD. A consistent approach to platelet transfusion in the NICU. J Matern Fetal Neonatal Med 2012;25:93–6. Borges JP, dos Santos AM, da Cunha DH, et al. Restrictive guideline reduces platelet count thresholds for transfusions in very low birth weight preterm infants. VoxSang 2013;104:207–13. Gerday E, Baer VL, Lambert DK, et al. Testing platelet mass versus platelet count to guide platelet transfusions in the neonatal intensive care unit. Transfusion 2009;49:2034–9. Stanworth SJ, Clarke P, Watts T, et al. Platelets and neonatal transfusion study group, prospective, observational study of outcomes in neonates with severe thrombocytopenia. Pediatrics 2009;124:826–34. Muthukumar P, Venkatesh V, Curley A, et al.; Platelets Neonatal Transfusion Study Group. Severe thrombocytopenia and patterns of bleeding in neonates: results from a prospective observational study and implications for use of platelet transfusions. Transfus Med 2012;22:338–43. Peta¨ja¨ J, Andersson S, Syrja¨la¨ M. A simple automatized audit system for following and managing practices of platelet and plasma transfusions in a neonatal intensive care unit. Transfus Med 2004; 14:281–8. Baer VL, Lambert DK, Henry E, et al. Do platelet transfusions in the NICU adversely affect survival? Analysis of 1600 thrombocytopenic neonates in a multihospital health care system. J Perinatol 2007;27:790–6. Baer VL, Lambert DK, Schmutz N, et al. Adherence to NICU transfusion guidelines: data from a multihospital health care system. J Perinatol 2008;28:492–7. Baer VL, Henry E, Lambert DK, et al. Implementing a program to improve compliance with neonatal intensive care unit transfusion guidelines was accompanied by a reduction in transfusion rate: a pre-post analysis within a multihospital health care system. Transfusion 2011;51:264–9.
