Abstract
OBJECTIVE: To compare biobehavioral pain responses of preterm infants born at differing gestational ages (GAs) when pain was preceded by a rest period or by a series of routine nursing interventions. METHODS: In a randomized, within subjects, cross-over design, facial (Neonatal Facial Coding System), sleep/wake state and heart rate (HR) responses of 43 preterm infants [mean birth weight: 1303 g (range 590 g to 2345 g); mean GA at birth: 30 weeks (range 25 to 32)] were examined across 3 phases of blood collection (Baseline, Lance, and Recovery) under 2 conditions: pain after a 30-minute rest period versus pain after a series of routine nursing interventions (clustered care). Infant behavioral responses were coded from continuous bedside videotapes. HR was analyzed using custom physiologic signal processing software. RESULTS: Infants born at earlier GA (<30 wk) had equally intense facial responses during the Lance phase regardless of condition. However, later born infants (> or =30 wk GA) showed heightened facial responses indicative of sensitized responses during blood collection when it was preceded by clustered care (P=0.05). Moreover, later born infants had significantly lower facial (P=0.05) and HR (P=0.04) reactivity during Recovery when blood collection followed clustered care. DISCUSSION: Earlier born preterm infants showed heightened states of arousal and poor ability to modulate HR during Recovery when an invasive procedure was preceded by routine tactile nursing procedures. Alternatively, later born infants exhibited sensitized responses when clustered care preceded blood collection. Our findings support the importance of cue based individualized approaches to care.