Kangaroo care for analgesia in preterm infants undergoing heel stick pain
Heelstick is the most common painful procedure in hospitalized premature infants and may be associated with impaired physiological, neurologic and immunologic functioning. The purpose was to examine Kangaroo Care (KC) effect on heelstick pain as measured by the Premature Infant Pain Profile (PIPP) and heart rate variability (HRV) indices.
Twenty-eight preterm infants 30-32 weeks gestational age were tested in a crossover design. Fourteen were randomized to group A (incubator heelstick [IH] on day1; KC heelstick [KCH] on day2) and 14 to group B (KCH on day1; IH on day2). The first 18 were tested in an 80-minute protocol and the last 10 in a 30-minute protocol.
During the Heel Stick phase, in the 30-min protocol subgroup, PIPP scores were lower in KCH (range 4.00-10.60) than IH (range 9.75-14.33) and the difference between KCH and IH were >2 points (considered clinically important). Repeated-measures analysis showed that PIPP was lower in KCH than IH at 0.5 minute after the stick in the Total Sample, p < .05. Infants had an average of 27% less pain in KCH than IH and KC had a large effect on reducing pain.
During the Recovery phase, KCH infants had less pain at three time points (p < .05-.001) in the 30-minute protocol subgroup and at 2 time points (p < .05) in the Total Sample. Pain was 21%-25% less in KCH than IH, and KC had medium effect on reducing pain.
In KCH compared to IH, low frequency (LF, sympathetic activity) and high frequency power (HF, parasympathetic activity) were higher during Baseline (p < .05.01); LF was higher during Heel Stick (p < .001); and LF/HF ratio (balance of sympathetic-parasympathetic activity) was lower during Recovery (p < .001). Infants had better balanced autonomic activity in KCH than IH during their response to heelstick. Infants also had a shorter duration of bradycardia, higher SaO2, less decrement in SaO2 from Baseline to Heel Stick, and shorter or no oxygen desaturation in KCH than 1H. In conclusion, KC reduced bio-behavioral and autonomic pain responses in preterm infants undergoing heelstick pain during the first 2-9 days of life.