ABSTRAK Bayi prematur mudah kehilangan panas, salah satunya saat dilakukan tindakan invasif pengambilan darah. Penelitian mengunakan crossover design desain ekperimen kontrol silang dimana melakukan 2 uji coba intervensi yang bertujuan membandingkan 2 tindakan yang berbeda pada sampel yang sama. Responden dibagi menjadi 2 kelompok A B masing-masing 18 bayi prematur. Analisis menggunakan uji statistik independent T,test. Tindakan invasif di inkubator pintu terbuka nilai p 0,001, secara statistik terdapat perbedaan rerata yang bermakna terhadap penurunan suhu tubuh bayi prematur; sedangkan radiant warmer nilai p 0,001 secara statistik terdapat perbedaan rerata yang bermakna terhadap peningkatan suhu tubuh bayi prematur sebelum dan sesudah tindakan invasif pengambilan darah di bawah radiant warmer. Radiant warmer mampu menghindari terjadinya hipotermia pada bayi prematur saat dilakukan tindakan invasif. Radiant warmer sebagai pemancar hangat dapat direkomendasikan untuk melakukan tindakan invasif pengambilan darah, tetapi tidak digunakan untuk perawatan secara rutin karena dapat meningkatkan IWL. ABSTRACT The premature infants tend to heat loss quickly. It can be occurred when they get invasive procedure venous puncture. The research uses crossover design by conducting 2 intervention tests to compare 2 different treatment to the same sample. This research involves two group of respondents A and B with consists of 18 premature infants in each group. The process of data analisys uses statistical Independent T.Test. Intervention are conducted in open incubator p value 0,001 statistically range related to heat loss in premature infants. On the other hand, radiant warmer p value 0,001 statistically refers to the defferent range of heat gain before and after invasive procedure for venous puncture is given radiant warmert. Radiant warmer prevent the premature infant from hypothermia during invasive procedure. As its benefit, it becomes the preferable way to do invasive procedure. However, it is inadvisable for routine care of newborn infant since it can increase IWL |