Effects of plasma transfusions on antithrombin levels after paediatric liver transplantation

BACKGROUND AND OBJECTIVES

Thrombotic complications affect 3-10% of patients after liver transplantation (LT), leading to potentially life-threatening complications. In the days following LT, antithrombin (AT) is decreased longer than pro-coagulant factors, thus favouring a pro-thrombotic profile. Plasma transfusions are given empirically in some centres to correct AT levels following LT. We assessed the effect of plasma transfusion on AT levels after paediatric LT.

MATERIALS AND METHODS

Prospective single-centre observational study in 20 consecutive paediatric LT recipients over a 24-month period. Plasma was administered twice daily (10 ml/kg/dose) according to an existing protocol. AT levels were measured once daily, immediately prior to and one hour after the morning plasma transfusion. Sample size was calculated based on a non-inferiority hypothesis.

RESULTS

The median age and weight were 11.6 years (IQR 2.8; 14.7) and 40 kg (IQR 12.75; 44.8), respectively. We collected 85-paired blood samples. The median AT level prior to plasma transfusion was 58%. The median difference in AT levels before and after plasma transfusion was 4.2% (P = 0.001). Changes in AT levels after plasma transfusion were not correlated with baseline AT levels (R = 0.19) or patient weight (R = 0.18).

CONCLUSION

Plasma transfusions only marginally increase AT levels in children after LT. Therefore, prophylactic plasma transfusions probably do not seem to confer an advantage in the routine management of paediatric LT patients. Randomized controlled trials are needed to identify the optimal anticoagulation strategy in this specific population.

Factors influencing plasma transfusion practices in paediatric intensive care units around the world

BACKGROUND AND OBJECTIVES

Plasma transfusions are a frequent treatment worldwide, but many studies have reported a wide variation in the indications to transfuse. Recently, an international paediatric study also showed wide variation in frequency in the use of plasma transfusions: 25% of the centres transfused plasma to >5% of their patients, whereas another 25% transfused plasma to <1% of their patients. The objective of this study was to explore the factors associated with different plasma transfusion practices in these centres.

MATERIALS AND METHODS

Online survey sent to the local investigators of the 101 participating centres, in February 2016. Four areas were explored: beliefs regarding plasma transfusion, patients' case-mix in each unit, unit's characteristics, and local blood product transfusion policies and processes.

RESULTS

The response rate was 82% (83/101). 43% of the respondents believed that plasma transfusions can arrest bleeding, whereas 27% believe that plasma transfusion can prevent bleeding. Centres with the highest plasma transfusion rate were more likely to think that hypovolaemia and mildly abnormal coagulation tests are appropriate indications for plasma transfusions (P = 0·02 and P = 0·04, respectively). Case-mix, centre characteristics or local transfusion services were not identified as significant relevant factors.

CONCLUSION

Factors influencing plasma transfusion practices reflect beliefs about indications and the efficacy of transfusion in the prevention and management of bleeding as well as effects on coagulation tests. Educational and other initiatives to target these beliefs should be the focus of research.

The effect of inhaled nitric oxide in acute respiratory distress syndrome in children and adults: a Cochrane Systematic Review with trial sequential analysis

Acute respiratory distress syndrome is associated with high mortality and morbidity. Inhaled nitric oxide has been used to improve oxygenation but its role remains controversial. Our primary objective in this systematic review was to examine the effects of inhaled nitric oxide administration on mortality in adults and children with acute respiratory distress syndrome. We included all randomised, controlled trials, irrespective of date of publication, blinding status, outcomes reported or language. Our primary outcome measure was all-cause mortality. We performed several subgroup and sensitivity analyses to assess the effect of inhaled nitric oxide. There was no statistically significant effect of inhaled nitric oxide on longest follow-up mortality (inhaled nitric oxide group 250/654 deaths (38.2%) vs. control group 221/589 deaths (37.5%; relative risk (95% CI) 1.04 (0.9-1.19)). We found a significant improvement in PaO₂ /F_I O₂ ratio at 24 h (mean difference (95% CI) 15.91 (8.25-23.56)), but not at 48 h or 72 h, while four trials indicated improved oxygenation in the inhaled nitric oxide group at 96 h (mean difference (95% CI) 14.51 (3.64-25.38)). There were no statistically significant differences in ventilator-free days, duration of mechanical ventilation, resolution of multi-organ failure, quality of life, length of stay in intensive care unit or hospital, cost-benefit analysis and methaemoglobin and nitrogen dioxide levels. There was an increased risk of renal impairment (risk ratio (95% CI) 1.59 (1.17-2.16)) with inhaled nitric oxide. In conclusion, there is insufficient evidence to support inhaled nitric oxide in any category of critically ill patients with acute respiratory distress syndrome despite a transient improvement in oxygenation, since mortality is not reduced and it may induce renal impairment.

Association between plasma transfusions and clinical outcome in critically ill children: a prospective observational study

BACKGROUND AND OBJECTIVES

Plasma transfusions are commonly used in adult and paediatric intensive care units. Recent data suggest an association between plasma transfusions and worse clinical outcome in adult trauma patients. To date, no prospective paediatric study has addressed this issue. Our objective was to prospectively analyse the association between plasma transfusions and clinical outcome of critically ill children.

MATERIALS AND METHODS

Prospective, observational and single centre study that includes all consecutive admissions to a tertiary level multidisciplinary paediatric critical care unit over a 1-year period. The primary outcome measure was the incidence after transfusion of new or progressive multiple organ dysfunction syndrome. Secondary outcome measures included nosocomial infections, intensive care unit length of stay and 28-day mortality. Odds ratios were adjusted for weight, severity of illness, coagulopathy, plasma transfusions prior to admission, need for extracorporeal life support and transfusion of other labile blood products.

RESULTS

A total of 831 patients were enrolled, among which 94 (11%) received at least one plasma transfusion. In the latter group of patients, the adjusted odds ratio for an increased incidence of new or progressive multiple organ dysfunction syndrome was 3.2 (P = 0.002). There was also a significant difference in the occurrence of nosocomial infections and intensive care unit length of stay, but no significant difference in the 28-day mortality.

CONCLUSIONS

In critically ill children, plasma transfusions seem to be independently associated with an increased occurrence of new or progressive multiple organ dysfunction syndrome, nosocomial infections and prolonged length of stay.

National survey on abdominal trauma practices of pediatric surgeons

INTRODUCTION

Pediatric blunt abdominal trauma is a frequent reason for hospital admission, but there are no established guidelines to assess these patients. Our study aims to evaluate the diagnostic process used by pediatric surgeons in Switzerland to evaluate abdominal trauma.

MATERIAL AND METHODS

A scenario-based survey was carried out among Swiss pediatric surgeons. Respondents were asked to report on their management of children with blunt abdominal trauma.

RESULTS

The response rate was 46% (26 of 54). The clinical signs considered the most important were abdominal examination and palpation (100%), auscultation (81%), external genital exam (77%) and Glasgow Coma Scale (77%). The most frequent laboratory exams requested were urine analysis (100%), complete blood count (96%), liver function tests (85%) and coagulation tests (77%). 42% of the physicians asked for an abdominal ultrasound for every patient with blunt abdominal trauma. 58% reported that some patients do not need a CT scan despite anomalies in the initial workup. There were significant variations in the clinical assessment of patients with minor blunt abdominal trauma. Abnormal ultrasounds, but not abnormal liver functions tests, prompted clinicians to obtain CT scans. When evaluating the probability of organ injury after a full workup, clinicians relied on the results of the ultrasound but not on liver function tests. A normal CT scan did not appear to reassure physicians if the patient still presented with mild abdominal pain.

CONCLUSIONS

There is a wide variation in the clinical assessment, request for laboratory tests and use of radiological exams among Swiss pediatric surgeons. Further studies are required on the evaluation of abdominal organ injuries in children.

Noise levels during nCPAP are flow-dependent but not device-dependent

OBJECTIVE

Nasal continuous positive airway pressure (nCPAP) has been shown to improve the outcome of infants with respiratory distress syndrome. However, noise generation could be of concern. Therefore, our study was designed to measure the noise levels of various CPAP drivers.

DESIGN

For infants admitted to our neonatal intensive care unit and paediatric critical care unit, we measured the noise level in the oral cavity, using a microphonic probe with a flexible capillary tube. Various CPAP drivers and interfaces have been tested.

RESULTS

27 measurements were made in eight infants. Mean noise level was 88.6 (SD 18.8) dB and was correlated with flow (p<0.01) but not with pressure. A noise level above 90 dB was detected in 67% of the measurements.

CONCLUSIONS

nCPAP drivers are valuable devices for neonatal care that may prevent primary mechanical ventilation or re-intubation, but generate a large amount of noise, often higher than occupational limits accepted for adult workers. Therefore, new devices must be designed to minimise this possible noxious exposure of premature infants to unacceptably high noise levels.

Liver function tests in children with blunt abdominal traumas

BACKGROUND

Previous studies have suggested that there are cut-off values for liver function tests (LFTs) beneath which significant liver injury can be excluded after blunt abdominal trauma in children. Our objective is to test this hypothesis in our patient population.

METHODS

The LFTs of all consecutive patients admitted in Geneva from January 1, 2001 to December 31, 2004 following blunt abdominal trauma were analysed and compared to radiological (ultrasound and/or computed tomography scan) findings and final outcome.

RESULTS

Of 115 patients identified, sixteen had radiological evidence of liver injury. These patients had significantly (p < 0.01) increased aspartate aminotransferase (AST) and alanine aminotransferase (ALT) values (474 +/- 369 IU/l and 442 +/- 383 IU/l, respectively) compared to patients without liver injury (AST 88 +/- 161 IU/l and ALT 68 +/- 137 IU/l). Among the sixteen patients with liver injury, ten (63 %) had AST < 450 IU/l and seven (44 %) had ALT < 250 IU/l. Two patients had radiological evidence of OIS grade 3 liver injury with AST as low as 95 and 92, and ALT of 80 and 86, below all cut-off values recommended in the literature.

CONCLUSION

In our experience, low LFT values at admission could not rule out significant liver injury. The diagnosis of such lesions still relies on clinical and radiological findings, as do other intra-abdominal organ injuries.