Primary hemostasis in fetal growth restricted neonates studied via PFA-100 in cord blood samples

BACKGROUND

Platelet function of fetal growth restricted (FGR) neonates remains a field of debate. Platelet function analyzer (PFA-100) offers a quantitative in vitro assessment of primary, platelet-related hemostasis. Our aim was to examine platelet function using PFA-100 in FGR neonates and associate our results with perinatal parameters.

METHODS

PFA-100 was applied on 74 FGR neonates, 48 full-term (>37 weeks' gestation) and 26 preterm neonates (<37 weeks). The control group consisted of 118 healthy neonates. Two closure times (CTs) with COL/EPI and COL/ADP cartridges were determined on cord blood samples for each subject. Statistical analysis was performed by SAS 9.4. The statistical significance level was set at 0.05 and all tests were two-tailed.

RESULTS

COL/EPI CTs were prolonged in FGR (median 132 s, IQR 95-181 s) compared with control neonates (median 112.5 s, IQR 93-145 s), p = 0.04. Median COL/EPI CT for term and preterm FGR neonates was 126 s (IQR 90-157 s) and 137 s (IQR 104-203), respectively (p = 0.001), and COL/ADP CT was 70 s (IQR 62-80 s) for term and 75 s (IQR 68-82 s) for preterm FGR neonates (p = 0.08). Among FGR neonates, COL/EPI CT was related with delivery time (with preterm neonates exhibiting prolonged COL/EPI CTs), p = 0.05. No correlation was proved between both CTs and hematological parameters in FGR neonates.

CONCLUSION

FGR neonates showed impaired platelet function via PFA-100, with preterm FGR neonates confronting the greatest risk. Prolonged COL/EPI CTs in FGR neonates seemed to be independent of hematological parameters and could warn for closer evaluation during the first days of their lives.

High-Risk Pregnancies and Their Impact on Neonatal Primary Hemostasis

Primary hemostasis, similar to other systems in the adjusting and transitioning neonate, undergoes developmental adaptations in the first days of life. Although platelets of neonates do not differ quantitatively compared with those of adults, they functionally present with major differences, thus supporting the theory of a "hypofunctional" phenotype that is counterbalanced by high hematocrit and more potent von Willebrand factor multimers. No clinical effect of bleeding tendency has hence been established so far for healthy term neonates. However, discrepancies in functionality have been noted, associated with gestational age, with more pronounced platelet hyporesponsiveness in preterm neonates. Multiple methods of in vitro platelet function evaluation such as PFA-100/200, platelet aggregometry, flow cytometry, and cone and platelet analyzer have been used for assessment of neonatal primary hemostasis. Several pregnancies are characterized as "high-risk" when risk factors preexist in maternal history or evolve during pregnancy. These pregnancies require specialized observation as they may have unpredictable outcome. High-risk pregnancies include clinical entities such as preeclampsia, pregnancy-induced smoking during pregnancy, gestational diabetes mellitus (GDM), autoimmune diseases, and other maternal hematological conditions. In some cases, like systemic lupus erythematosus, antiphospholipid antibody syndrome, and maternal immunologically based thrombocytopenia, neonatal thrombocytopenia is regarded as a prominent hemostasis defect, while in others, like pregnancy-induced hypertension and preeclampsia, both quantitative and qualitative disorders of neonatal platelets have been reported. In other pathologies, like GDM, neonatal primary hemostasis remains vastly unexplored, which raises the need for further investigation. The extent to which primary hemostasis is affected in neonates of high-risk pregnancies is the main objective of this narrative review.

Congenital diaphragmatic hernia and double-outlet right ventricle: elements of trisomy 18?

We present a case of a term male neonate born with congenital diaphragmatic hernia (CDH), double-outlet right ventricle (DORV) and a “picture of genetic syndrome”, antenatally diagnosed, without any confirmation of a particular syndrome as no amnioparacentesis was performed. The postnatal chromosomal analysis revealed trisomy 18.

Spontaneous Fertility in a Male Thalassemic Patient after Allogeneic Hematopoietic Cell Transplantation

Patients with thalassemia major who received allogeneic hematopoietic cell transplantation are at increased risk of gonadal insufficiency and reduced fertility due to the toxicity of both the transfusional iron overload and the gonadotoxic effects of drugs used in the conditioning regimen. We present a case of an ex-thalassemic patient with spontaneous recovery of spermatogenesis that fathered a healthy, term male neonate. Maternal hemoglobin electrophoresis was within normal limits. At the age of 9.5 years the patient underwent hematopoietic cell transplantation. The conditioning therapy included busulfan (16 mg/kg) and cyclophosphamide (200 mg/kg). No irradiation was administered. Thirty-two days after the hematopoietic cell transplantation the patient developed acute graft-versus-host disease needing long-term treatment with methylprednisolone, cyclosporine and immunoglobulin. Although consecutive semen analyses after the hematopoietic cell transplantation revealed azoospermia, the last semen analysis before conception, at the age of 33 years, was improved and normal follicle stimulating hormone (FSH), luteinizing hormone (LH) and testosterone (Te) levels were detected. The current pregnancy was the result of physical conception. In this case, it seems that thalassemia major along with the respective treatment prior to- and posthematopoietic cell transplantation did not irreparably impair spermatogenesis, probably due to the pre-pubertal time frame they were implemented.

Sodium replacement and plasma sodium drop during exercise in the heat when fluid intake matches fluid loss

CONTEXT

Sodium replacement during prolonged exercise in the heat may be critically important to maintaining fluid and electrolyte balance and muscle contractility.

OBJECTIVE

To examine the effectiveness of sodium-containing sports drinks in preventing hyponatremia and muscle cramping during prolonged exercise in the heat.

DESIGN

Randomized crossover study.

PATIENTS OR OTHER PARTICIPANTS

Thirteen active men.

INTERVENTION(S)

Participants completed 4 trials of an exercise protocol in the heat (30 degrees C) consisting of 3 hours of exercise (alternating 30 minutes of walking and cycling at a heart rate of 130 and 140 beats per minute, respectively); a set of standing calf raises (8 sets of 30 repetitions); and 45 minutes of steep, brisk walking (5.5 km x h(-1) on a 12% grade). During exercise, participants consumed fluids to match body mass loss. A different drink was consumed for each trial: carbohydrate-electrolyte drink containing 36.2 mmol/L sodium (HNa), carbohydrate-electrolyte drink containing 19.9 mmol/L sodium (LNa), mineral water (W), and colored and flavored distilled water (PL).

MAIN OUTCOME MEASURE(S)

Serum sodium, plasma osmolality, plasma volume changes, and muscle cramping frequency.

RESULTS

During both HNa and LNa trials, serum sodium remained relatively constant (serum sodium concentration at the end of the protocol was 137.3 mmol/L and 136.7 mmol/L, respectively). However, a clear decrease was observed in W (134.5 +/- 0.8 mmol/L) and PL (134.4 +/- 0.8 mmol/L) trials compared with HNa and LNa trials (P < .05). The same trends were observed for plasma osmolality (P < .05). Albeit not significant, plasma volume was preserved during the HNa and LNa trials, but a reduction of 2.5% was observed in the W and PL trials. None of the volunteers experienced cramping.

CONCLUSIONS

The data suggest that sodium intake during prolonged exercise in the heat plays a significant role in preventing sodium losses that may lead to hyponatremia when fluid intake matches sweat losses.