Presurgical Use of Hypoxic Mixture for Systemic Perfusion Improvement in Neonates With Complex Congenital Heart Disease: A Systematic Review and Meta-Analysis.

Oxygen therapy is essential for the survival of preterm babies and critically ill newborns; however, it has the potential to cause harm through hypoxemia or hyperoxemia. Newborns with complex congenital heart diseases (CHD) suffer from oxygen fluctuations due to the disease and its treatments, altering pre and postnatal development. The objective of this study is to evaluate the evidence for using a hypoxic mixture to decrease pulmonary over-circulation and improve systemic perfusion before surgical interventions in newborns with complex CHD that course with pulmonary over-circulation and systemic hypoperfusion. A search was conducted in PubMed, EMBASE, LILACS, Scielo, Taylor and Francis, SAGE, and Science Direct databases from 2000 to 2022 by two independent authors, including articles with hypoxic mixture treatment in observational studies or trials, with pre-treatment and post-treatment measurements in the same patient, or two groups or more comparisons. Six articles were selected, with a total of 75 patients. The primary outcome was improved systemic circulation and decreased pulmonary over-circulation measured directly with Qp/Qs and indirectly with oxygen saturation and cerebral near-infrared spectroscopy (NIRS). In addition, we performed a meta-analysis for oxygen saturation and cerebral NIRS. Oxygen saturation was the value uniformly reported; three studies reported a significantly lower oxygen saturation after the hypoxic mixture. The cerebral NIRS was measured in 4 studies, with inconsistent results. After using the hypoxic mixture, the Qp/Qs calculation was lower in the two studies but was not statistically significant. The meta-analysis for oxygen saturation showed a fixed effect post-hypoxic therapy of -0.7 (-1.06; -0.35), p < 0.001. The meta-analysis of two studies that measured cerebral NIRS did not show a statistically significant difference at 12 and 24 hours. In conclusion, this is the first systematic review and meta-analysis regarding the pre-operative use of hypoxic gas mixtures for newborns with complex congenital heart disease. Treatment results in lower oxygen saturations, but there is a lack of evidence of improvement in systemic perfusion. The utilization of this therapy is controversial, and better evidence is necessary.

Difficult acute lymphoblastic leukaemia diagnosis in a paediatric patient with mixed presentation of COVID-19 acute respiratory failure and multisystemic inflammatory syndrome.

New diagnoses of leukaemia and other malignancies are recently being made in paediatric patients with COVID-19. The rates of mortality and morbidity in some of these children are expected to be higher. In new cases, concurrent diagnosis can be difficult because multisystemic inflammatory syndrome (MIS-C) and malignancies have similar clinical presentations. We present the case of a preteenage child where the diagnosis of leukaemia was complicated and delayed by a multisystem involvement and an inconclusive bone marrow study. Clinical teams managing children with COVID-19 and MIS-C should suspect leukaemia and other malignancies when the clinical course is complicated and bone marrow suppression is persistent. Prompt diagnosis will allow start of treatment on time, minimising complications.

Methylene blue for the treatment of refractory septic shock secondary to listeriosis in a paediatric patient.

Current therapies frequently used for refractory septic shock include hydrocortisone, vasopressin, extracorporeal membrane oxygenation (ECMO) support, inodilators, levosimendan and methylene blue. The evidence for these treatments is very limited. We present a case of a 5-year-old patient with refractory septic shock, secondary to Listeria monocytogenes meningitis. She presented with status epilepticus and developed septic shock. Shock persisted despite multiple high-dose vasoactive medications. ECMO support was not available. The medical team decided to use methylene blue to revert the vasoplegia, with excellent results. Shortly after the administration, vasopressors were weaned off and the high lactate cleared. She developed severe neurological sequelae due to brain haemorrhage secondary to the Listeria meningitis. The evidence supporting methylene blue for refractory septic shock in paediatric patients is limited. This case represents the effectiveness of this therapy without secondary effects.

Rhabdomyosarcoma in adults: new perspectives on therapy.

OPINION STATEMENT: Rhabdomyosarcoma (RMS) is well known as a pediatric disease. Most of the knowledge, like biology, genetics, and treatments of this disease, comes from studies done in that age group. The two subtypes of RMS, embryonic RMS and alveolar RMS, that affect mainly the pediatric population are well described in the literature and that has had an impact on the improvement in overall survival during the past 20 years. RMS in the adult population has a low incidence, therefor the study of RMS in this group is challenging. Pleomorphic RMS is the subtype that mainly affects adults and its biology and genetics are not yet completely understood and described. The risk factors for this tumor and the differences among adults and children is also poorly understood. The treatments for adults that have RMS are not standardized having an impact on the overall survival. Pleomorphic RMS has, compared to other adult sarcomas, poor overall survival. Adult patients with RMS have poor prognosis. The standardization of treatments for the adult population is necessary as maybe new treatments for this specific group. There are new treatment options that are being studied mostly in pediatrics and young adults. Immunotherapy is currently proposed as an important treatment possibility including different techniques like vaccination, antigen-mediated therapy, and immune checkpoints. Even if we have a better understanding of RMS, there are still unanswered questions. The improvements seen in the pediatric population are encouraging, but there is still the need to enhance better therapies for adults with RMS.