Subcutaneous fat necrosis in neonates with hypoxic ischaemic encephalopathy registered in the Swiss National Asphyxia and Cooling Register

Abstract

BackgroundNeonates with hypoxic ischaemic encephalopathy (HIE) are routinely treated with therapeutic hypothermia (TH) for 72 h in order to improve neurological outcome. Subcutaneous fat necrosis (SCFN) is an adverse event occurring in neonates with HIE.MethodsWe analyzed risk factors for SCFN regarding demographic factors, cooling methods and deviation from target temperature range during hypothermia therapy. Data of all neonates registered in the National Asphyxia and Cooling Register in Switzerland between 2011 and 2013 were analyzed.Results2.8 % of all cooled neonates with HIE developed SCFN. Perinatal and neonatal characteristics did not differ between neonates with and without SCFN. Applied cooling methods did not correlate with the occurrence of SCFN. In neonates with SCFN 83.3 % of all noted temperatures were within the target temperature range versus 77.5 % in neonates without SCFN. Neonates with SCFN showed 3.6 % of all measured temperatures below target temperature range compared to 12.7 % in neonates without SCFN.ConclusionSubcutaneous fat necrosis in the neonate with HIE undergoing TH is a potential adverse event that seems to occur independently from the whole-body cooling method applied and proportion of temperature measurements outside target temperature range. In this cohort, moderate overcooling associated with moderate hypothermia (33.0–34.0 °C) does not seem to be an independent risk factor for SCFN. There is no correlation between the severity of HIE and incidence of SCFN.Electronic supplementary materialThe online version of this article (doi:10.1186/s12887-015-0395-7) contains supplementary material, which is available to authorized users.

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

“…Asphyxia is a well‐recognised SCFN risk factor that causes sympathetic activation, circulatory redistribution of blood flow away from the skin and thus a reduction of skin blood flow . Therapeutic hypothermia also is a widely recognised risk factor for SCFN in newborns .…”

Neonatal subcutaneous fat necrosis with hypercalcemia treatment using calcitonin

“… 7 Notably, prednisone which is used to reduce the granulomatous inflammatory process and vitamin D production can increase urinary calcium excretion, thereby elevating a patient’s risk of nephrocalcinosis. 8 In the present case study, the patient was treated with vitamin D supplements following hydration and treatment with furosemide. The patient was not showing any improvement and the calcium level was not declining either.…”

Cooled infants with encephalopathy: are heavier infants with weaker heart at a cutaneous disadvantage?

“…Exposure of skin to the extreme low temperature may worsen the dermal vasoconstriction predisposing the adipose tissue to solidification resulting in SCFN. However, in a small number of cooled infants (n = 4), SCFN seems to occur independent of the cooling method, and the proportion of measured temperature outside the target range, implying the exposure of skin to extreme low temperature of the blanket remained comparable between infants with and without SCFN . Subcutaneous fat necrosis of the newborn is diagnosed clinically and there is a potential to misdiagnose sclerema or scleroderma as SCFN although the former two occurs in sick premature infants in the first week of life and lacks fat necrosis in the histological evaluation .…”

“…The incidence of SCFN in infants with perinatal asphyxial encephalopathy varies from 0.9% to 2.8% . Interestingly, the multicentre randomised controlled trials of therapeutic hypothermia in infants with perinatal asphyxial encephalopathy that have collectively recruited 763 infants between them reported only one infant with SCFN .…”

“…Several predisposing factors for SCFN drawn mainly from small case series have been reported in the literature including (i) maternal factors such as gestational diabetes, pre‐eclampsia; (ii) perinatal factors such as traumatic delivery, perinatal asphyxia, hypothermia and (iii) neonatal factors such as thrombocytosis . Since the introduction of therapeutic hypothermia (reducing core temperature to 33.5°C) as the standard of care for newborn infants with moderate‐to‐severe perinatal asphyxial encephalopathy, case reports of SCFN in therapeutically cooled infants with perinatal asphyxial encephalopathy and reports of SCFN from national registries of infants cooled for perinatal asphyxial encephalopathy have emerged . These suggest asphyxia and hypothermia as risk factors for SCFN.…”