Relationship between platelet mass index and postoperative atrial fibrillation after elective coronary artery bypass surgery: a retrospective study.

BACKGROUND: Atrial fibrillation (AF) is the most common complication after cardiac surgery. The pathogenesis of postoperative atrial fibrillation (POAF) is multifactorial and one of the known factors is inflammation. Platelet mass index (PMI) is an indicator of platelet activation and a better inflammatory marker than mean platelet volume (MPV). In this retrospective study, we investigated the relationship between POAF and PMI. METHODS: The study included 848 consecutive patients (655 male and 193 female) who had elective isolated coronary artery by-pass grafting (CABG) or combined CABG and valvular surgery. Platelet count and MPV were measured from preoperative blood samples to calculate PMI. Post-operative atrial fibrillation was defined as irregular and fibrillatory P waves occurring 48-96 h after cardiac surgery and lasting at least 30 s. The PMI values in patients who developed POAF were compared with those in patients who did not develop POAF. RESULTS: Patients who developed POAF had higher PMI values (2549.3 ± 1077.1) when compared with patients in sinus rhythm (2248.1 ± 683.4; p < 0.01). In multivariate regression analysis, age (OR: 1.05; 95% CI: 1.02-1.09; p = 0.01), left atrial diameter (OR: 1.05; 95% CI: 1.03-1.09; p = 0.02), hs-CRP (OR: 1.09; 95%CI: 1.05-1.13; p < 0.01), EuroSCORE II (OR: 1.27; 95% CI: 1.14-1.41; p < 0.01), and PMI (OR: 1.01; 95% CI: 1.001-1.02; p < 0.01) were independent predictors of POAF. In ROC analysis, PMI ≥ 2286 predicted POAF development with a sensitivity of 69% and a specificity of 58% (AUC: 0.66; p < 0.01) CONCLUSION: A significant relationship was found between preoperatively calculated PMI and POAF. We showed that PMI may be used to predict patients who are at high risk of developing POAF.

The relationship between platelet indices and patent ductus arteriosus in preterm infants: a systematic review and meta-analysis.

Patent ductus arteriosus (PDA), one of the most common disorders in newborns, is associated with many complications in premature infants such as respiratory distress syndrome (RDS) and bronchopulmonary dysplasia (BPD). However, the diagnosis of hemodynamically significant patent ductus arteriosus (hsPDA) is still an ongoing debate. The relationship between platelet parameters and hsPDA has been explored in many studies over the last decade, but there is still no definite conclusion. We aim to explain the relationship between platelet parameters and hsPDA through this meta-analysis. Therefore, we used PubMed, Embase, the Cochrane Library, and Web of Science databases as well as the Google Scholar to search for studies up to May 2020. Three reviewers independently screened the articles, evaluated the quality of the articles, and collected the data. The random-effects model and fixed-effects model were used to evaluate pooled results. We used the I-square (I2) test to examine heterogeneity and the funnel plot; Egger's test and meta-regression analysis were used to test for publication bias. Influence analysis was also carried out in this study. Stata version 12.0 software was used for data analysis. Fourteen studies, which included 3330 newborns, were extracted from 986 studies. The weighted mean difference (WMD) of the platelet count was - 17.98 (p < 0.001), the platelet distribution width (PDW) was 0.27 (p = 0.266), the mean platelet volume (MPV) was 0.01 (p = 0.958), the plateletcrit (PCT) was - 0.03 (p < 0.001), and the platelet mass was - 150.10 (p = 0.001).Conclusion: Platelet count, PCT, and platelet mass of the first 3 days of life are potentially helpful in identifying premature infants at risk of hsPDA. More prospective studies on the relationship between different degrees of thrombocytopenia and platelet function and hsPDA should be conducted. What is Known: • Platelets are involved in the formation of thrombi during closure of the arterial duct. • The diagnosis of hsPDA by Doppler echocardiography and clinical signs is not precise enough. What is New: • Preterm newborns with hsPDA in the first week of life demonstrated a significant reduction in platelet count, platelet mass, and plateletcrit in the first 3 days of life. • No significant difference was shown between hsPDA and non-hsPDA infants in platelet distribution width and mean platelet volume in the first 3 days of life.

Comparison of Platelet Mass Index in On-Pump and Off-Pump Coronary Artery Bypass Surgery.

INTRODUCTION: Platelet mass index (PMI) is calculated by multiplying platelet count and mean platelet volume (MPV). It demonstrates platelet activation and is thought to be associated with inflammation. Its importance for cardiac surgery has not yet fully been clarified. This study investigates whether there is a difference between PMI levels after on-pump and off-pump coronary artery bypass surgery and the relationship between early postoperative complications and PMI. METHOD: In our hospital, 138 patients were included in the study retrospectively. The patients were divided into 2 groups: Group 1 (on-pump) with 80 patients (22 females, 58 males, mean age 61.54 ± 8.68) and Group 2 (off-pump) with 58 patients (15 females, 43 males, mean age 61.34 ± 10.04). In biochemical analysis, hemoglobin, platelet, white blood cell, and MPV values of the patients were evaluated in the biochemistry laboratory of our hospital with the blood taken preoperatively from the forearm veins and postoperatively on the first, third, and seventh days and, on average, after the first month. RESULTS: There was a statistically significant difference between postoperative first day thrombocyte (K/µL) (P = .005), postoperative first day PMI (P = .014), postoperative first day leukocyte (K/µL) (P = .001), postoperative first day Hb (g/dL) (P = .001), postoperative third day thrombocyte (K/µL) (P = .003), postoperative third day PMI (P = .031), postoperative third day leukocyte (K/µL) (P = .004), and postoperative seventh day leukocyte (K/µL) (P = .002). There was no meaningful relationship between PMI and early postoperative complications. CONCLUSION: We think PMI is a more valuable indicator than MPV as an inflammation marker in cardiac surgery. In our opinion, PMI is a cheap and valuable inflammation marker that can be used in coronary surgery that can be obtained from routine hemogram test and can easily be evaluated.

Platelet mass index and prediction of severity of transient tachypnea of the newborn.

BACKGROUND: Platelet mass index (PMI) is associated with platelet functionality. The aim of this study was to evaluate the role of PMI in predicting the severity of transient tachypnea of the newborn (TTN). METHODS: Infants with gestational age ≥37 weeks and birthweight ≥2,000 g who were given nasal intermittent mandatory ventilation for TTN ≤6 h after birth were retrospectively enrolled in this study. PMI was calculated using the following formula: PMI = platelet count × mean platelet volume/103 (fL/nL). The study infants (n = 101) were divided into two groups according to the duration of tachypnea: ≤48 h (n = 45) and >48 h (n = 56). RESULTS: The PMI and platelet count were significantly lower in the group with tachypnea duration >48 h than in the tachypnea duration ≤48 h group (P < 0.001 and P = 0.04, respectively). A negative significant correlation was noted between PMI and the duration of tachypnea (r = -0.43, P < 0.001). A PMI cut-off of 1,562 fL/nL can predict prolonged tachypnea (>48 h) with a sensitivity of 62.5%, specificity of 68.9%, positive predictive value of 71.4%, and negative predictive value of 59.6% (area under the curve, 0.682 ± 0.053; P = 0.002). CONCLUSIONS: Lower PMI and lower platelet count are associated with longer duration of tachypnea in patients with TTN.

The Impact of Duration and Force of Centrifugation on Platelet Content and Mass in the Preparation of Platelet-Rich Plasma.

PURPOSE: Platelet-rich plasma (PRP) is an autologous prepared plasma enriched with platelets and obtained after a centrifugal separation and aggregation procedure. However, the optimized preparation protocol for PRP is still controversial and there are no standardized preparation protocols. The aim of this study is to show the effect of time and force of the centrifugation on the concentrations of platelets and to optimize the effective PRP preparation protocol. METHODS: For the study, whole blood was drawn into 24 different 6-ml standard tubes containing 0.6 ml anticoagulant citrate dextrose solution-formula A. The samples were centrifuged separately at forces of 45×g, 180×g, 400×g, 725×g, 1130×g and 1630×g for 5, 10, 15 and 20 min. Every sample was analyzed, and a comparison was made between all groups. RESULTS: No significant difference was observed in terms of platelet concentration, mean platelet volume or platelet mass between all groups (p > 0.05). The mean ± SD of platelet mass in baseline is 1890 ± 134 × 103 fL/µL. The mean ± SD of platelet mass in the high centrifugal force of 1630×g was 3395 ± 564 × 103 fL/µL, 2638 ± 425 × 103 fL/µL, 2355 ± 449 × 103 fL/µL and 2109 ± 41 × 103 fL/µL over times of 5, 10, 15 and 20 min, respectively. The mean ± SD of platelet mass in the low centrifugal force of 45×g was 2002 ± 1623 × 103 fL/µL, 2491 ± 1591 × 103 fL/µL, 2611 ± 876 × 103 fL/µL and 3003 ± 511 × 103/µL over times of 5, 10, 15 and 20 min, respectively. CONCLUSIONS: Platelets should be evaluated with platelet mass not including platelet concentrations alone, but also with mean platelet volume, which symbolizes the size of platelets while comparing platelet-rich plasma preparation protocols and kits. This could be a new starting point for comparison of PRP for all applications in the literature. All centrifugation forces and times could produce biologically reactive PRP. It may be only suggested that if high acceleration force is used, low durations should be selected, or if low acceleration force is used, long time of centrifugation should be selected. NO LEVEL ASSIGNED: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Transfusing neonates based on platelet count vs. platelet mass: a randomized feasibility-pilot study.

The objective of this study was to obtain pilot data on which to judge the feasibility and sample size needed for a future comparative-effectiveness trial of platelet transfusions in the NICU. We conducted a limited-scope pilot trial in which neonates were randomized to receive platelet transfusions based on platelet mass vs. platelet count, using preset "transfusion-trigger" values. Analysis included parental consent rate, number of platelet transfusions given, bleeding episodes recorded, and mortality rate. Statistical analysis included ANOVA and Chi-square. A convenience sample of 30 were randomized; 15 per group. No differences were found between groups in gestational age, birth weight, race, gender or clinical diagnoses. The study consent rate was 52% (30/58). No differences were found in number of platelet transfusions received, bleeding episodes, or mortality. Lack of a trend in transfusion-reduction resulted in inability to estimate the number needed in a future comparative-effectiveness trial. Using platelet mass, rather than platelet count, for a NICU platelet transfusion trigger is feasible. However, any future comparative-effectiveness trial, testing the hypothesis that a platelet mass-based trigger reduces the transfusion rate will likely require a very large sample size.

Effect of Glycemic Control on Platelet Indices in Children with Type 1 Diabetes Mellitus.

Objectives: The aim of this study is to compare children diagnosed with type 1 diabetes mellitus (T1DM) with healthy controls in terms of some laboratory parameters and platelet indices. Methods: This study is retrospective. We used glycated hemoglobin (HbA1c) values to classify patients as <7% (good) and ≥7% (poor). The platelet mass (PM) value was calculated from the hemogram data (PM=PLTxMPV). Results: The study included a total of 87 patients who had been diagnosed with T1DM and 120 healthy participants. Fasting glucose, urea, creatinine, hemoglobin (HGB), red blood cell (RBC), mean platelet volume (MPV) and platelet distribution width (PDW) were significantly higher in the patient group than in the healthy control group. Platelet (PLT), plateletcrit (PCT) and PM were significantly lower in the poor glycemic control than in the good glycemic control and healthy groups. The PDW in the healthy control group was statistically significantly lower than in the good and poor glycemic control groups. In the group with poor glycemic control, there was a positive and significant correlation between the MPV and the level of HbA1c (r=0.401, p<0.05). Conclusion: To sum up, our results show that the MPV and the PDW are significantly higher in children with T1DM than in healthy control. In the group with poor glycemic control, PLT levels were significantly lower than in the other two groups, leading to a decrease in PCT and PM levels. Further studies are needed to understand whether the decrease in PLT levels is due to the hyperactivity and rapid turnover of PLT.

The Usability of Platelet Mass Index Thresholds to Assess the Repeated Platelet Transfusion Requirements in Neonates.

To evaluate the usability of platelet mass index (PMI) thresholds to assess the repeated platelet transfusion requirements in neonates who have received transfusion within the previous six days. This is a retrospective cross-sectional study conducted with neonates who received prophylactic platelet transfusion. The PMI was calculated as platelet count (× 1000/mm3) × mean platelet volume (MPV) (fL). Platelet transfusions were divided into two groups as first (Group 1) and repeated transfusions (Group 2). The increment and percentage of increment in platelet counts, MPV and PMI after transfusion were compared between the two groups. The amounts of changes were calculated as: (Post-transfusion) - (Pre-transfusion values). The percentages of changes were calculated as: ([Post-transfusion - Pre-transfusion values]/Pre-tansfusion values) × 100. Eighty three platelet transfusions were analyzed in 28 neonates. The median gestational age and birth weight were 34.5 (26-37) weeks, and 2225 (752.5-2937.5) grams, respectively. There were 20 (24.1%) transfusions in Group 1, and 63 (75.9%) transfusions in Group 2. There were no differences in the amounts of changes in platelet counts, MPV and PMI between the groups (p > 0.05). When the percentages of changes were analyzed, it was found that the platelet counts and PMI in Group 1 increased to a greater extent compared to Group 2 (p = 0.026, p = 0.039, respectively), but no significant difference was found in MPV between the groups (p = 0.081). The lower percentage of change in PMI in Group 2 was associated with the lower percentage of change in platelet counts. Being transfused with adult platelets did not affect platelet volume of the neonates. Therefore, PMI thresholds can be used in neonates with a history of platelet transfusion.

Early onset neonatal thrombocytopenia is associated with severe intraventricular hemorrhage in very preterm infants: A retrospective cohort study.

BACKGROUND: The role of platelet function in the development of intraventricular hemorrhage is still a subject of debate. In this study, we aimed to determine whether there is an association between platelet indices in the first week of life and severity of intraventricular hemorrhage in very preterm infants. MATERIALS AND METHODS: Preterm infants born < 30 weeks of gestation in our hospital were retrospectively evaluated. Platelet parameters, including platelet counts, mean platelet volume, platelet distribution width, and platelet mass were retrieved at two different time points: the initial value on the first day of life and the value closest to the end of the first week of life. The infants were categorized according to the findings of cranial ultrasonography as; no intraventricular hemorrhage, mild or severe intraventricular hemorrhage. RESULTS: Totally, 1051 infants were evaluated. The mean gestational age and birth weight for the entire cohort were 27.9±1.6 weeks and 1058±247 g, respectively. Infants in the severe intraventricular hemorrhage group had significantly lower gestational age (p < 0.001) and birthweight (p < 0.001) compared to other two groups. Furthermore, there were significant differences in platelet count and platelet mass between the groups at two time intervals. However, logistic regression analysis revealed that only platelet count of < 100×109/L on the first postnatal day was independently associated with the severity of intraventricular hemorrhage. CONCLUSION: There is an association between platelet count of < 100×109/L on the first postnatal day and severe intraventricular hemorrhage in very preterm infants.

Performance of Platelet Mass Index as a Marker of Severity for Sepsis and Septic Shock in Children.

Platelet mass index (PMI) as a prognostic indicator in pediatric sepsis has not been previously reported. In this retrospective observational study, we evaluated PMI's performance as a prognostic indicator in children aged younger than 18 years with sepsis and septic shock in relationship with survival. Over 5 years, we collected data from 122 children admitted to our pediatric intensive care unit (PICU). PMI accuracy was assessed with sensitivity and specificity and its discrimination was assessed using the area under the receiver operating characteristic curve (AUC). Median PMI values on days 1 and 3 of PICU admission were lower among nonsurvivors. On day 1 of PICU admission, a cutoff PMI value of 1,450 fL/nL resulted in a sensitivity of 72% and a specificity of 69%, and the AUC was 0.70 (95% confidence interval [CI]: 0.55-0.86). Similarly, on day 3, a cutoff of 900 fL/nL resulted in a sensitivity of 71% and a specificity of 70%, and the AUC was 0.76 (95% CI: 0.59-0.92). Our exploratory study suggests that low PMI in children with septic shock is associated with increased mortality. Considering the PMI's fair performance, further studies should be performed to assess its clinical value.

Hematologic Risk Factors for the Development of Retinopathy of Prematurity-A Retrospective Study.

(1) Background: Retinopathy of prematurity (ROP) can cause severe visual impairment or even blindness. We aimed to assess the hematological risk factors that are associated with different stages of ROP in a cohort of preterm newborns, and to compare the clinical characteristics and therapeutic interventions between groups. (2) Methods: This retrospective study included 149 preterm newborns from a tertiary maternity hospital in Romania between January 2018 and December 2018, who were segregated into: Group 1 (with ROP, n = 59 patients), and Group 2 (without ROP, n = 90 patients). The patients that were affected by ROP were subsequently divided into the following subgroups: Subgroup 1 (Stage 1, n = 21), Subgroup 2 (Stage 2, n = 35), and Subgroup 3 (Stage 3, n = 25). The associations were analyzed using multivariate logistic regression and sensitivity analysis. (3) Results: Platelet mass indexes (PMI) that were determined in the first, seventh, and tenth days of life were significantly associated with Stage 1 ROP. PMI determined in the first day of life was also significantly associated with Stage 2 ROP. The sensitivity and specificity of these parameters were modest, ranging from 44 to 57%, and 59 to 63%. (4) Conclusions: PMI has a modest ability to predict the development of ROP.

Relationship between hematological parameters and bronchopulmonary dysplasia in premature infants.

OBJECTIVE: To evaluate the association between hematological parameters on the first day of life and bronchopulmonary dysplasia (BPD) in preterm infants. METHODS: This retrospective study involved all premature infants admitted to our neonatal intensive care unit from January 2017 to June 2022. BPD was diagnosed based on hypoxia exposure for ≥28 days. The neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), platelet count (PLT), mean platelet volume (MPV), and platelet mass index (PMI) were compared between infants with and without BPD. Multivariate analysis was conducted to evaluate the association between hematological parameters and BPD. RESULTS: This study involved 124 premature infants (48 with BPD, 76 without BPD). The BPD group had a lower gestational age and lower weight. The NLR, MPV, and PLR were considerably higher and the PLT and MPI were lower in the BPD than non-BPD group. After adjusting for covariates, logistic regression analysis suggested that the NLR, PLT, and PMI were independent risk factors for BPD. Moreover, the receiver operating characteristic curve indicated that the NLR, PLT, and PMI were reliable predictors of BPD. CONCLUSION: Our findings suggest that a higher NLR and a lower PLT and PMI on the first day may increase the risk of BPD.

Relationship between platelet indices in acute cholecystitis: A case-control study.

INTRODUCTION AND AIMS: We aimed to investigate changes in initial platelet indices in patients arriving at the emergency department with acute cholecystitis. MATERIAL AND METHODS: A retrospective case-control study was conducted at a tertiary care teaching hospital. Demographics, comorbidities, laboratory data, length of hospital stay, and mortality data for the acute cholecystitis group were retrospectively obtained from the hospital digital database. Platelet count, mean platelet volume, plateletcrit, platelet distribution width, and platelet mass index were collected. RESULTS: A total of 553 patients with acute cholecystitis were the study cases, and 541 hospital employees were the study controls. According to the results of the multivariate analysis of the platelet indices studied, only mean platelet volume and platelet distribution width showed significant differences between the two groups (adjusted odds ratio: 2, 95% confidence interval: 1.4-2.7, p < 0.001 and adjusted odds ratio: 5.88, 95% confidence interval: 2.44-14.4, p < 0.001, respectively). The multivariate regression model created had an area under the curve of 0.969 in the prediction of acute cholecystitis (accuracy: 0.917, sensitivity: 89%, and specificity: 94.5%). CONCLUSION: The study results indicate that the initial mean platelet volume and platelet distribution width were independent predictors of acute cholecystitis.

Relationship between histomorphological findings and platelet activation in psoriasis.

BACKGROUND: Elevated platelet count (PC), mean platelet volume (MPV), and Platelet Mass Index (PMI) are reported in patients with psoriasis, while platelet activation is associated with psoriasis severity. Available studies examining the relationship between platelet activation markers and psoriasis have mostly focused on psoriasis area severity index. To the best of our knowledge, there is no study examining the relationship between histopathological features of a single psoriatic plaque and platelet activation. The present study examined the relationship between histomorphological findings obtained by morphometric analysis and psoriasis patients' PC, MPV, and PMI values. MATERIALS AND METHODS: Morphometric analysis was performed on hematoxylin and eosin-stained preparations of skin biopsies to measure minimum suprapapillary epidermis thickness (SPETmin ) and maximum epidermal thickness (ETmax ), maximum suprapapillary keratosis thickness (SPKTmax ), and maximum keratosis thickness (KTmax ). The relationship between PC, MPV, PMI, and morphometric skin biopsy outcomes was evaluated. RESULTS: While an inverse correlation was found between SPETmin and PC and PMI in cases with psoriasis (p values = 0.015 and 0.005, r values = -0.238 and -0.271, respectively), no significant correlation was found between SPETmin and MPV (p value = 0.600, r value = -. 052). On the contrary, no significant correlation was found between SPKTmax, ETmax, and KTmax values and platelet parameters. CONCLUSION: We assume that an increased risk of platelet activation-related diseases is expected in psoriasis patients displaying histopathological findings of suprapapillary thinning due to increased platelet activation; therefore, it may be beneficial to monitor these patients in terms of such risks.

Association of platelet indices with glycemic status in diabetic dogs.

We investigated the platelet count (PLT), mean platelet volume (MPV), and plateletcrit (PCT) in dogs with type 1 diabetes mellitus (DM) compared to healthy controls, and their association with the major fraction of glycated hemoglobin (HbA1c). Blood samples from 33 clinically healthy dogs and 14 newly diagnosed diabetic dogs were included. CBCs were performed with the Advia 120; HbA1c was determined using a validated assay (Capillarys 2 flex-piercing; Sebia). Median [range] PLT and PCT were significantly higher (p = 0.040 and p = 0.010, respectively) in diabetic dogs (434 [176-987] × 109/L and 0.60 [0.26-1.22]%, respectively) compared to healthy dogs (297 [223-671] × 109/L and 0.35 [0.24-0.87]%, respectively]. Thrombocytosis was observed in 6 of 14 (43%) diabetic dogs. The median MPV was not significantly different (p = 0.114) between the diabetic (13.6 fL, 10.1-22.6 fL) and healthy dogs (11.9 fL, 8.6-19.1 fL). A significant, albeit weak, correlation was detected between HbA1c and PLT (rho = 0.298, p = 0.042) and PCT (rho = 0.340, p = 0.019), but no significant correlation was found with MPV (rho = 0.199, p = 0.180). Canine DM was associated with increased PLT and PCT, which was correlated with glycemic status. Our findings suggest dysregulated megakaryopoiesis in diabetic dogs, but this should be confirmed by large-scale studies, and the clinical implications should be investigated.

Platelet Mass Index and Other Platelet Parameters in the Assessment of Inflammatory Bowel Diseases Activity.

Different qualitative and quantitative changes in platelets are involved in the pathophysiological processes in inflammatory bowel diseases (IBD): ulcerative colitis (UC) and Crohn's disease (CD). The aim of the study was to determine the diagnostic accuracy of Platelet mass Index (PMI) and other platelet parameters in assessment disease activity in patients with UC and CD. A cross-sectional, observational study consisted of 60 IBD patients (30 UC and 30 CD) and 30 healthy subjects (Control group). Patients were grouped according to disease activity into active and inactive (remission). Platelet count (PLC), Plateletcrit (PCT), Mean Platelet Volume (MPV), Platelet Distribution Width (PDW) and PMI were determined for all study participants. Receiver operating characteristic (ROC) curve and their corresponding areas under the curve (AUC) were used to determine diagnostic accuracy. Although PLC had the highest AUC (0.756) compared to PCT (AUC: 0.731), PDW (AUC: 0.722) and PMI (AUC: 0.724), they all had fair diagnostic accuracy in distinguishing active and inactive UC patients. Discriminatory accuracy of PLC was excellent (AUC: 0.909), PCT and PMI good to excellent (AUC: 0.809 and AUC: 0.893, respectively) and PDW fair (AUC: 0.789) in classifying CD patients as active and inactive. Platelet parameters are simple, routinely available biomarkers more useful for assessing disease activity for patients with CD than for patients with UC. Our results indicate, for the first time, that PMI may serve as a novel and simple marker in identifying whether IBD patients are in the active or inactive phase of the disease.

Neonatal Thrombocytopenia and the Role of the Platelet Mass Index in Platelet Transfusion in the Neonatal Intensive Care Unit

Background: Neonatal thrombocytopenia is a common hematological abnormality that occurs in 20­35% of all newborns in the neonatal intensive care unit. Platelet transfusion is the only known treatment; however, it is the critical point to identify neonates who are really at risk of bleeding and benefit from platelet transfusion as it also has various potential harmful effects. Aims: To investigate the prevalence and risk factors of neonatal thrombocytopenia and its relationship to intraventricular hemorrhage in the neonatal intensive care unit and to determine whether the use of platelet mass index-based criteria could reduce the rate of platelet transfusion. Study Design: Retrospective cohort study. Methods: This study was conducted in the neonatal intensive care unit of a tertiary university hospital. The medical records of neonates in the neonatal intensive care unit with platelet counts <150×109/L between January 2013 and July 2016 were analyzed. Results: During the study period, 2,667 patients were admitted to the neonatal intensive care unit, and 395 (14%) had thrombocytopenia during hospitalization. The rate of intraventricular hemorrhage was 7.3%. Multiple logistic regression analysis showed that although lower platelet counts were associated with a higher intraventricular hemorrhage rate, the effects of respiratory distress syndrome, sepsis, and patent ductus arteriosus were more prominent than the degree of thrombocytopenia. Thirty patients (7%) received platelet transfusion, and these patients showed a significantly higher mortality rate than their non-platelet transfusion counterparts (p<0.001). In addition, it was found that the use of platelet mass index-based criteria for platelet transfusion in our patients would reduce the rate of platelet transfusion by 9.5% (2/21). Conclusion: Neonatal thrombocytopenia is usually mild and often resolves without treatment. As platelet transfusion is associated with an increased mortality rate, its risks and benefits should be weighed carefully. The use of platelet mass index-based criteria may reduce platelet transfusion rates in the neonatal intensive care unit, but additional data from prospective studies are required.

Is the First Postnatal Platelet Mass as an Indicator of Patent Ductus Arteriosus?

BACKGROUND: The aim of this study is to evaluate whether there is an association between the platelet mass and patent ductus arteriosus (PDA) closure in premature newborns. METHODS: Preterm infants (gestational age ≤33 weeks) with hemodynamically significant PDA (group 1, n = 178) and a control group of preterm infants without PDA (group 2, n = 211) were retrospectively evaluated between August 1, 2013 and July 30, 2015 in the neonatal intensive care unit (NICU). Platelet counts and platelet indices including mean platelet volume (MPV), and platelet mass (platelet count x mean platelet volume) in the first 24 hours of life, demographic findings and morbidities were recorded. RESULTS: No differences were observed in demographic findings between the study groups in terms of birth weight, gestational age, gender and maternal risk factors. The mean platelet count in the first postnatal hemogram in group 1 and group 2 were 189.43 ± 72.14 (X103 /mm3) and 206.86 ± 70.11(X103/mm3), respectively (P < 0.05). The MPV were similar in both groups (P > 0.05). Platelet mass values were 1443.70 ± 572.40 fL/nL in Group 1 and 1669.49 ± 1200.42 fL/nL in group 2. There was a statistically significant difference in platelet mass values between the two groups (P = 0.011). Multivariable analysis including presence of thrombocytopenia, MPV and platelet mass showed that hemodynamically significant PDA was not independently associated with platelet count <150 000 (OR = 1.001, 95% CI 0.980-1.023; P = 0.921), MPV (OR = 0.967, 95% CI 0.587-1.596; P = 0.897) or platelet mass (OR = 0.999, 95% CI 0.997-1.002; P = 0.681). The optimal cut-off value of platelet mass for patients with PDA was ≤1530.8 fL/nL (area under the curve [AUC]: 0.580), with sensitivity of 58% and specificity of 56.2% (P = 0.008). CONCLUSION: Our data suggest that platelet count, MPV, and platelet mass do not contribute to closure of PDA in premature newborns.

An important and overlooked parameter in platelet rich plasma preparation: The mean platelet volume.

BACKGROUND: The platelets are the most heterogeneous cellular elements of the blood in size whereas larger platelets have more granules that make them more reactive rather than their smaller counterparts. OBJECTIVES: The aim of this study is to report the distribution of platelets in the plasma after centrifugation steps. METHODS: Twelve healthy male subjects were enrolled.5.4 mL of whole blood samples were collected for each tube containing 0.6 mL of acid citrate dextrose. Four samples were centrifuged at the force of 180 × g for 15 minutes. Then, 0.6 mL buffy coat was drawn from one of the four centrifuged tubes and 1/3 of the lower layer of the plasma (1.0 mL) from the second centrifuged tube; 1/3 of the middle(1.0 mL) and 1/3 of the upper layer (1.0 mL) of the plasma from third and fourth ones were drawn for blood analysis. RESULTS: Blood analysis including MPV and platelet concentrations were significantly different between the layers (P < .05). Together buffy coat and lower third of plasma layers contain 87% of the entire platelet mass. CONCLUSIONS: Platelets should not be argued only with their concentration, but it would be appropriate to evaluate with their yielded concentration and volume with MPV together while comparing PRP preparation protocols and kits.

Platelet mass index can be a reliable marker in predicting the prognosis of retinopathy of prematurity in very preterm infants.

BACKGROUND: Retinopathy of prematurity (ROP) is a proliferative vitreoretinopathy resulting from vascular defect of the retina. The present study evaluates platelets, which are involved in VEGF storage, transport and release, and their functions with regard to the prognosis of the disease. The objective was to suggest a simple minimal invasive method that will facilitate the management of the disease and help clinicians in predicting the prognosis. METHODS: In this single center, retrospective, case-control study, we included a control group consisting of very preterm newborns (n = 83) at risk of ROP and a laser photocoagulation group including infants (n = 63) who received laser therapy during their follow-up examinations. The employed assessments included platelet counts and platelet mass index (PMI) which provide guidance in understanding platelet activity. In doing so, consideration was given to the first and second phases of ROP. The accuracy of prognostication was assessed with receiver operating characteristic analyses. RESULTS: The study groups did not differ statistically significantly by platelet count during the first and second phases of ROP (p > 0.05) nor were the PMI measurements statistically significantly different between the study groups during the first phase of the disease (p > 0.05). PMI values of the study groups, however, differed significantly in the second phase of ROP (p < 0.05). CONCLUSION: The present study found a significant difference between the two groups in PMI measurements which reflect increased VEGF levels during the neovascularization phase, which underlies the disease. This conclusion demonstrated that monitoring the PMI values in newborns at risk of ROP can be considered to be a minimally invasive method that by changing the retinal examination procedure in use today which is rather troublesome for both the physician and the newborn, can provide facilities in monitoring the disease for both the physician and the newborn.