J Pediatr (Rio J). 2018;94(4):337---339 www.jped.com.br EDITORIAL Preventing hypothermia in preterm newborns --- simple ଝ,ଝଝ principles for a complicated task Prevenc¸ão de hipotermia em recém-nascidos prematuros --- princípios simples para uma tarefa complicada Joaquim M.B. Pinheiro Albany Medical Center, Department of Pediatrics/Neonatology, Albany, United States Hypothermia is a major contributor to newborn mortal- rate from 37% at baseline to 14% in the post-intervention 1,2 ity worldwide and remains a common problem for very era, with a minimal increase in hyperthermia rates. The low birthweight (VLBW) infants, even in technologically study design precludes evaluation of whether confounders 3,4 advanced hospital settings. The attributable risk of mor- such as decreased prophylactic surfactant administration tality from hypothermia is difficult to establish from the contributed to the reported results. Without data to scant randomized trials on delivery room stabilization of measure compliance with the thermoregulation process 5 VLBW newborns, but the relationship between admis- (e.g., delivery room temperature, % plastic bags never 6 sion temperature and neonatal morbidities is U-shaped, opened), it is also unclear whether further improvement suggesting that both hypothermia and hyperthermia are would be possible just by perfecting the current practices. undesirable. Consequently, the recommended goal for Nevertheless, the authors’ team attained clinically impor- postnatal stabilization is to maintain a normothermic tem- tant improvements without resorting to additional physical ◦ 7 perature between 36.5 and 37.5 C. In the past decade, assets and using apparently minimal human resources several reports have documented success in decreasing for QI. hypothermia rates at neonatal intensive care unit (NICU) This study illustrates several important points about min- 4,8 admission, although high rates of hyperthermia were con- imizing neonatal hypothermia. First, Caldas’ data, similarly 9,10 comitantly induced in some studies. to those from most of our NICUs, demonstrate that clini- In this issue of Jornal de Pediatria, Caldas et al. report cians cannot assume that simply using technologies such as the results of a quality improvement (QI) intervention to a radiant warmer will effectively prevent hypothermia in decrease hypothermia in VLBW newborns admitted to a very preterm newborns. Indeed, in the baseline period, even 11 Brazilian NICU. They successfully reduced the hypothermia when combining multiple evidence-based methods includ- ing a plastic bag and increased delivery room temperature, 12 among others, hypothermia was frequent. It was only with consistent application of the same methods, including DOI of original article: attention to details such as keeping the bag closed dur- http://doi.org/10.1016/j.jped.2017.06.016 ଝ ing auscultation and other resuscitation interventions, that Please cite this article as: Pinheiro JM. Preventing hypothermia 11 normothermia was reliably maintained. in preterm newborns --- simple principles for a complicated task. J Second, hypothermia is not a condition that requires evi- Pediatr (Rio J). 2018;94:337---9. ଝଝ See paper by Caldas et al. in pages 368---73. dence from randomized clinical trials to establish which E-mail: [email protected] thermoregulatory interventions are effective. We know that https://doi.org/10.1016/j.jped.2017.10.003 0021-7557/© 2017 Sociedade Brasileira de Pediatria. Published by Elsevier Editora Ltda. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). 338 Pinheiro JM a newborn’s temperature will inevitably increase with any remains too frequent, the care process must be redesigned, exothermic heat source; conversely, its decrease will be and it may be necessary to add other interventions to the slowed by any interventions that diminish heat loss. How- thermoregulation bundle, such as thermal mattress. ever, to preserve thermal stability in practice, we must To achieve the highest levels of thermoregulatory per- know how to reliably apply the basic principles of ther- formance, the care team would benefit from engaging in modynamics while resuscitating thermally labile newborns. collaborative QI with other centers. This provides not only Thermoregulation in the immediate postnatal period is external benchmarks for realistic improvement, but also largely passive, with heat exchange occurring along thermal a variety of potentially better practices, i.e., ideas for gradients through well-known physical mechanisms, namely, which there is no formal evidence from randomized trials, evaporation, convection, conduction, and radiation. The but that are associated with superior results (e.g., ther- rate and proportional contribution of each heat exchange moregulation bundles). NICUs that engage in collaborative mechanism varies with different patient and environmental QI have achieved better thermoregulation outcomes than 15 conditions. Heat balance can theoretically be maintained those whose QI efforts are exclusively local. It should be despite large evaporative and convective losses, if sufficient noted that the components of successful thermoregulation exogenous heat is provided --- generally from radiant and bundles may vary across sites and time, and must be adapted conductive sources. However, rapid rates of heat loss and to the local physical environment and resources. In our set- gain can quickly generate temperature instability and acci- ting, for example, warm blankets were used to partially dental hyperthermia. Consequently, the easiest and safest compensate for an administrative decision to remove chem- 16 way to maintain normothermia is to minimize heat losses, ical warming packs, and additional methods were needed thereby minimizing the need for exothermic input. Because when competing institutional policies precluded raising the 4 heat losses occur through multiple physical mechanisms, temperature of the cesarean section rooms. Finally, elimi- a ‘‘bundle’’ or combination of complementary methods is nating rare residual cases of hypothermia requires additional essential to counteract such losses, while providing exoge- local effort, including a debriefing after each event, using an 4,7 nous heat as needed. informal root cause analysis framework, so that appropriate A third lesson from this study is that neonatal care teams corrections can be made in the care processes. can attain substantial initial improvements in thermoregula- Throughout the various stages of this improvement work, tion without substantial added material or personnel costs. it is important to track balancing measures of hypother- The authors provided education to promote compliance with mia prevention, as possible indicators of adverse effects existing processes, and leveraged existing data, which were of the new processes. The most obvious balancing measure analyzed every six months, to provide feedback to the is hyperthermia, indicating overtreatment, whereas lower NICU staff. Ideally, a QI process involving rapid Plan-Do- Apgar scores and other complications of resuscitation may Study-Act cycles would involve continuous data analysis and signal interference of thermoregulation efforts with basic display current results at the front lines of care for great- ventilation. Another essential consideration is the cost of 13,14 est impact ; while this requires additional staff time, interventions, which may vary considerably depending on it also increases awareness, accelerates staff compliance, whether the primary resources introduced include expensive and creates multidisciplinary team spirit and support for the new radiant warmers and disposable chemical mattresses, project. or inexpensive plastic wrap and warm blankets. Having recognized the extent of the admission hypother- Admission hypothermia is becoming less prevalent, but mia problem, standardized evidence-based practices, and it still occurs in about 40% of VLBW newborns in the Ver- 17 successfully decreased hypothermia rates in their VLBW mont Oxford Network, which indicates that all NICUs patients, Caldas et al. humbly conclude that there is still have opportunities for improvement. As Caldas et al. room for improvement in this measure in their NICU, and demonstrate, improvement can be readily accomplished by 11 they set their next benchmark rate at 10%. Which steps carefully considering the basic principles of thermodynam- might they take to improve further? Would those steps be ics --- minimizing heat loss and providing a combination of generalizable to other NICUs? radiant and conductive heat. Ideally, tight thermal control When admission hypothermia is frequent in a NICU, sim- of individual neonates by continuous monitoring with a skin ple observation of delivery room stabilization will likely probe (where available) during postnatal transition, coupled reveal obvious causes of heat loss by one or more of the with continuous monitoring of QI data at the NICU level, four heat transfer mechanisms. Systematically countering should rapidly minimize the incidence of both hypothermia as many of those causes as deemed feasible by a multidis- and hyperthermia. Monitoring at the individual and institu- ciplinary QI team of delivery room and NICU staff (including tional levels will be important as the context of newborn physicians, nurses, and other support staff as needed) should resuscitation evolves; presently, increases in cold exposure rapidly produce improved results.