Macrosomia and haemodynamic instability may represent risk factors for subcutaneous fat necrosis in asphyxiated newborns treated with hypothermia

Proposing a care practice bundle for neonatal encephalopathy during therapeutic hypothermia

Neonates with neonatal encephalopathy (NE) often present with multi-organ dysfunction that requires multidisciplinary specialized management. Care of the neonate with NE is thus complex with interaction between the brain and various organ systems. Illness severity during the first days of birth, and not only during the initial hypoxia-ischemia event, is a significant predictor of adverse outcomes in neonates with NE treated with therapeutic hypothermia (TH). We thus propose a care practice bundle dedicated to support the injured neonatal brain that is based on the current best evidence for each organ system. The impact of using such bundle on outcomes in NE remains to be demonstrated.

Subcutaneous fat necrosis associated with hypercalcemia in neonates with neonatal encephalopathy treated with therapeutic hypothermia

Subcutaneous fat necrosis of the newborn (SFNN) is a rare, self-resolving panniculitis. The onset of skins lesions occurs within the first week of life, with a median age of onset around day 6 of life (range 1-70). About 50% of neonates with SFNN will develop hypercalcemia in the first month though some present later. Typically, SFNN develops prior to hypercalcemia. Only half of the neonates have classic symptoms of hypercalcemia; routine screening for hypercalcemia is recommended for neonates with SFNN or at-risk. The mechanism for hypercalcemia is usually aberrant 1,25-dihydroxyvitamin D synthesis in the necrotic tissue increasing intestinal absorption of calcium. Prompt recognition and treatment is required, often in hospital. Treatment options are low calcium-vitamin D formula or sometimes intravenous bisphosphonates. Regular monitoring post-intervention is required when normalizing the diet. Outcomes are good with routine surveillance and interventions. A multidisciplinary team approach (neonatologists, pediatric endocrinologists and nephrologists, dieticians) is optimal.

Subcutaneous fat necrosis of the newborn - An atypical case with typical complications

Subcutaneous fat necrosis of the newborn should be considered in newborns with suggestive skin lesions, even in the absence of perinatal distress. SCFN may cause long-standing complications, like hypertriglyceridemia or hypercalcemia. Hypercalcemia can be refractory to therapy and lead to poor weight gain and nephrocalcinosis, which should be closely monitored.

System Specific Effects of Therapeutic Hypothermia with Neonatal Encephalopathy: Pearls for Clinicians

Neonatal encephalopathy (NE) is defined as a condition of impaired neurological function often caused by a peripartum event that impairs gas exchange resulting in hypoxia, hypercapnia, cerebral ischemia, and metabolic acidosis. NE is a significant cause of neonatal morbidity and mortality. Therapeutic hypothermia (TH) is the standard of care for the treatment of moderate and severe NE and has significantly improved long-term outcomes for affected infants. There are extensive systemic physiologic effects associated with TH that clinicians need to be aware of to optimize care for these infants. There is a paucity of literature that comprehensively identifies causal relationships between the physiologic and biochemical effects of TH. This can leave neonatal clinicians devoid of a comprehensive understanding of the medical management of NE. Therefore, this article seeks to help fill this gap, improve clinician knowledge base, and ultimately improve the care of infants undergoing TH.

Subcutaneous fat necrosis of the newborn

A term infant developed subcutaneous fat necrosis of the newborn (SFNN) 17 days following completion of therapeutic hypothermia for hypoxic ischaemic encephalopathy. Initial calcium was normal, however hypercalcaemia requiring hyperhydration and furosemide developed at 4 weeks. Parathyroid hormone and vitamin D were suppressed. At 13 months, she remains on low calcium formula, and has gross motor delay, central hypotonia and early hand preference. Review of 102 articles yielded 119 SFNN cases. Asphyxia was reported in 78%. Twenty-one per cent had hypoglycaemia. Twenty per cent underwent therapeutic hypothermia. Median onset of skin lesions was day 6 (range: 1-70), with a median duration of 62 days (range: 14-390). Hypercalcaemia developed in 53% (median onset day 28, range: 1-210). Fifty-two per cent of hypercalcaemia was asymptomatic. Outcome information was provided in 106/119 cases; 87% reported a full resolution. Persistent calcinosis was present in 6%. Babies treated with therapeutic hypothermia should be closely monitored for SFNN, and development of hypercalcaemia.

Feasibility of a Miniature Esophageal Heat Exchange Device for Rapid Therapeutic Cooling in Newborns: Preliminary Investigations in a Piglet Model

Therapeutic hypothermia (TH) after neonatal encephalopathy, commonly provided by 72 hours of whole-body cooling using a wrap, limits parents' physical contact with their infants affecting bonding and may not be suitable for encephalopathic preterm infants with fragile skin. Alternative cooling methods are unavailable for this population. We investigated in a neonatal pig model the feasibility of achieving a 3.5°C reduction in rectal temperature (T_rectal) similar to clinical TH protocols from 38.5°C (normothermia for pigs) to a target of 35°C ± 0.2°C, using a novel neonatal esophageal heat exchanger (NEHE), compared its efficacy to passive cooling, and investigated its ability to maintain target T_rectal. Ventilated and anesthetized Landrace/Large white newborn pigs had the NEHE inserted. Water at adjustable temperatures and rates flowed down a central tube, returning up a surrounding distensible blind ending latex tube in a continuous loop. An initial experiment guided four subsequent cycles of passive cooling (30 minutes), rewarming to 38.5°C, active esophageal cooling to 35°C ± 0.2°C, active maintenance of target T_rectal (30 minutes), and rewarming. We compared surface, rectal temperature, and hemodynamic changes among passive, active, and maintenance phases, and esophageal histopathology against control. Compared with passive cooling, esophageal cooling achieved target T_rectal significantly earlier (71.3 minutes vs. 17.25 minutes, p = 0.003) with significantly greater rates of reduction in rectal (p = 0.0002) and surface (p = 0.005) temperatures and heart rate (p = 0.04). A water temperature of 39.1°C-40.2°C at a flow of 108-120 mL/min maintained T_rectal around 35°C ± 0.2°C. The higher peak heart rate and blood pressure within 8 minutes of the maintenance phase (p = 0.04) subsequently stabilized. Histopathology showed congestion, edema, and neutrophil infiltration with increasing cycles. Esophageal cooling is feasible and effective in achieving rapid cooling in newborns. Subsequent maintenance at this temperature required continued circulation of warm water. Esophageal histopathology needs further evaluation after 72 hours servo-control cooling with a narrower range of water temperatures in a larger group of animals.