Movements Are Associated With Acute Pain in Preterm Infants in the Neonatal Specific Newborn Individualized Developmental Care and Assessment Program Specific Newborn Individualized Developmental Care and Assessment Program Movements Are Associated With A

ABSTRACT. Objective. The Newborn Individualized Developmental Care and Assessment Program (NIDCAP) is widely used in neonatal intensive care units and comprises 85 discrete infant behaviors, some of which may communicate infant distress. The objective of this study was to identify developmentally relevant movements indicative of pain in preterm infants. Methods. Forty-four preterm infants were assessed at 32 weeks' gestational age (GA) during 3 phases (baseline, lance/squeeze, and recovery) of routine blood collection in the neonatal intensive care unit. The NIDCAP and Neonatal Facial Coding System (NFCS) were coded from separate continuous bedside video recordings; mean heart rate (mHR) was derived from digitally sampled continuous electrographic recordings. Analysis of variance (phase ؋ gender) with Bonferroni corrections was used to compare differences in NIDCAP, NFCS, and mHR. Pearson correlations were used to examine relationships between the NIDCAP and infant background characteristics. Results. NFCS and mHR increased significantly to lance/squeeze. Eight NIDCAP behaviors also increased significantly to lance/squeeze. Another 5 NIDCAP behaviors decreased significantly to lance/squeeze. Infants who had lower GA at birth, had been sicker, had experienced more painful procedures, or had greater morphine exposure showed increased hand movements indicative of increased distress. Conclusions. Of the 85 NIDCAP behaviors, a subset of 8 NIDCAP movements were associated with pain. Particularly for infants who are born at early GAs, addition of these movements to commonly used measures may improve the accuracy of pain assessment. M ajor advances in neonatal care now enable a high proportion of preterm infants to survive. During a time when medical concerns focused primarily on stabilizing the physiologic needs of preterm infants, Als, a developmental psychologist, developed a theory and systematic method of assessing the developmental needs of preterm newborns, the Newborn Individualized Developmental Care and Assessment Program (NIDCAP). 1 Als hypothesized that early exposure to stress, or the mismatch of the preterm infant brain with the environment, could be linked to the long-term developmental impairments reported in these children at school age. 2 Since the early 1980s, the NIDCAP observation system has become widely used in neonatal intensive care units (NICUs) throughout North America and Europe. Several researchers have used the NIDCAP to assess body movements of infants in the NICU, but these studies either did not describe the procedures observed or did not include painful procedures. METHODS Study Subjects The infants were recruited by a NICU-trained research nurse, and written informed consent was obtained from the mother or other legal guardian according to a protocol approved by the Clinical Research Ethics Board of the University of British Columbia. The study sample included 44 preterm infants in the level III NICU in the Children's & Women's Health Centre of British Columbia (Vancouver, BC, Canada). The infants were Յ32 completed weeks' GA at birth, had no major congenital anomalies, and had no reported illicit maternal drug use during pregnancy. Infants who had received analgesics or sedatives within 72 hours of the assessment or who had significant intraventricular hemorrhage (grade III or IV) and/or parenchymal brain injury (periventricular leukomalacia) were excluded. All infants were 32 weeks' postconceptional age (PCA; Ϯ7 days) at the time of testing. Infant characteristics are presented in Measures All infants were observed during blood collection that was required for clinical management. The 3 phases of the procedure included in this study were a baseline period of 6 minutes of no handling immediately before the first contact by the laboratory technician (baseline); a blood collection period of 6 minutes from insertion of the lancet into the heel, which included the heel lance and squeezing (lance/squeeze); and an undisturbed recovery period of 6 minutes from the last contact of the laboratory technician (recovery). Infant State Infant sleep/wake state was coded according to the NIDCAP protocol 5 : 1 ϭ deep sleep; 2 ϭ light sleep; 3 ϭ drowsy; 4 ϭ quiet awake; 5 ϭ active awake; 6 ϭ highly aroused/crying; and 7 ϭ AA (prolonged respiratory pause Ͼ8 seconds). The predominant state during each 2-minute period was coded for each phase. Facial Activity (NFCS) The NFCS is a reliable, well-validated behavioral pain measure that is used widely in studies of term-born 19,31 and preterm infants. Full Body (NIDCAP) The NIDCAP behaviors were coded continuously, from video recordings of each infant, for the 3 phases (baseline, lance/ squeeze, and recovery), and coding was conducted blind to all clinical information. Following published NIDCAP procedures, the frequency of each infant's movements was recorded systematically in 2-minute time blocks. Heart Rate Continuous electrocardiographic activity was recorded from a single lead of surface electrocardiogram (lead II) and was digitally sampled at 360 Hz off-line using a specially adapted computer acquisition system. Custom physiologic signal processing software 38 was used to acquire, process, and analyze heart rate. R waves were detected from the sampled electrocardiogram and were used to form a smoothed instantaneous 4-Hz time series as described previously