Pain Response In Preterm Infants Research Articles

The effect of oscillometric blood pressure measurement on pain response in preterm infants.

Preterm neonates are exposed to many painful procedures in neonatal intensive care units. This study aims to evaluate the effect of oscillometric blood pressure (BP) measurement on pain response in preterm infants. This prospective study was performed over 4 months in a level III neonatal intensive care unit. Premature neonates whose gestational age was <34 weeks and postmenstrual age <36 weeks were included if they had no systemic diseases. BP measurement was performed on the right arm. The Premature Infant Pain Profile-Revised (PIPP-R) scores were evaluated three times before, during, and 10 min after BP measurement. During the 5-month period, 100 preterm neonates (53 male infants) were included in the study. Median birth weight and gestational age of the infants were 1148 (IQR: 1015-1300) g and 28 (IQR: 27-30) weeks, respectively. PIPP-R scores were found to be ≥7 in 34% of neonates. PIPP-R scores increased during BP measurement and decreased after. Our results demonstrated that oscillometric BP measurement which is generally accepted as a non-invasive tool for monitoring can produce mild pain in premature neonates of postmenstrual age <36 weeks.

Pain responses in preterm infants and parental stress over repeated painful procedures: a randomized pilot trial

Objectives In this pilot study, the aims were to determine the feasibility of whether pain behavior in extremely and very preterm infants and perceived parental stress change when parents are involved in pain reducing measures, either actively, performing facilitated tucking or passively, observing the intervention, in comparison to the involvement of nurses only. In addition, the infant’s pain reactivity and parental stress over three time points of measurement was of interest. Methods Extremely and very preterm infants in need of subcutaneous erythropoietin were randomly assigned to the two intervention groups. The intervention encompassed that one parent of each infant was involved during the painful procedure: Either parents executed facilitated tucking themselves or stood by, observing the procedure. Usual care involved that nurse executed facilitated tucking. All infants received 0.5 ml of 30% oral glucose solution via cotton swab before the painful procedure. Infant pain was observed with the Bernese Pain Scale for Neonates (BPSN) and measured with the MedStorm skin conductance algesimeter (SCA) before, during, and after the procedure. Parents’ stress levels were measured before and after the painful procedure on the infant, using the Current Strain Short Questionnaire (CSSQ). Feasibility of a subsequent trial was determined by assessing recruitment, measurement and active parental involvement. Quantitative data collection methods (i.e. questionnaires, algesimeter) were employed to determine the number of participants for a larger trial and measurement adequacy. Qualitative data (interviews) was employed to determine parents’ perspectives of their involvement. Results A total of 13 infants (98% participation rate) were included along with their mothers. Median gestational age was 27 weeks (IQR 26-28 weeks), 62% were female. Two infants (12.5%) dropped out of the study as they were transferred to another hospital. Facilitated tucking turned out to be a good method to actively involve parents in pain reducing measures. No significant differences between the two intervention and control groups were found concerning parental stress and infant pain (p = .927). Power analysis indicated that at least N = 741 infants (power of 81%, α = .05) would be needed to obtain statistically significant results in a larger trial, as effect sizes were smaller than expected. Two of the three measurement tools – i.e. the BPSN and CSSQ) – proved easy to implement and were well accepted. owever, the SCA was challenging in this context. Measurements were also found to be time-consuming and resource-intense (i.e. health professionals as assistants). Conclusions Although the intervention was feasible and was readily accepted by parents, the study design was found to be challenging along with the SCA. In preparation of the larger trial, the study design needs to be revisited and adjusted. Thus, issues of time and resources may be resolved. In addition, national and international collaboration with similar neonatal intensive care units (NICU) needs to be considered. Thus, it will be possible to conduct an appropriately powered larger trial, which will yield important results to improve pain management in extremely and preterm infants in NICU.

Echocardiography may cause significant pain response in preterm infants

Objective: The objective of this study is to evaluate if echocardiographic examination causes any pain response in term and preterm infants.Methods: Term and preterm neonates who admitted to Neonatal Intensive Care Unit at Gazi University Hospital and Etlik Zubeyde Hanim Training and Research Hospital and were performed echocardiography for any reason were included into the study. Neonates were evaluated before, during and 10 minutes after the examination. Vital signs (heart rate, respiratory rate, blood pressure, transcutaneous oxygen saturation) were recorded. All subjects were also evaluated with Neonatal Infant Pain Scale during the examination.Results: In this study, we evaluated 99 newborn infants. Five infants who received fentanyl treatment were excluded. The heart rate (p = 0.000), respiratory rate (p = 0.000), diastolic blood pressure (p = 0.001) and oxygen saturation (p = 0.000) during the examination were significantly different than the values before and 10 minutes after the examination. Infants whose gestational age ≤32 weeks (n:20) have significantly higher NIPS scores (mean ± SEM = 3.3 ± 0.4) than the infants whose gestational age is greater than 32 weeks (n:71) (mean ± SEM = 2.4 ± 0.2).Conclusions: Echocardiographic examination which is known as noninvasive and painless causes significant pain in preterm infants.

The Effect of Vanilla Odor on Response to Venipuncture Pain in Preterm Newborns: a Randomized Control Clinical Trial

Background: Studies have shown that use of olfactory stimuli during painful medical procedures reduces infants’ response to pain. Aim: The main purpose of this study was investigating the effect of vanilla on pain response in preterm infants during and after venipuncture. Methods: This study is a randomized clinical trial. Ninety preterm infants, who were randomly selected and divided into two groups of control and vanilla odor, were classified into 45 people. Infants in the vanilla group were exposed to vanilla odor from 5 minutes before and up to 30 seconds after sampling, and infants of control group were exposed to smell of distilled water. The pain score was measured using premature infant pain profile (PIPP) score 30 seconds prior, during and 30 seconds after sampling. Statistical analyses were done using SPSS 16 software. Analyses were done by t-test, chi-square and repeated measure analyses. Results: Despite the differences between the pain scores of two groups during and after sampling, statistical analyses showed no significant differences between them (p=0.36). Conclusion: Results of the present study showed that use of vanilla odor has no significant effect on premature infants’ pain during blood sampling.

Does skin-to-skin contact reduce stress during diaper change in preterm infants?

BackgroundSkin-to-skin contact reduces pain response in preterm infants subjected to minor painful procedures, such as heel lance. Diaper change is a procedure performed several times daily in hospitalized preterm infants. Routine care giving tasks such as diaper change may be stressful for the infant. AimsThe purpose of this study was to investigate whether diaper change induces stress and if skin-to-skin contact could reduce such stress, measured by changes in skin conductance. Study designThis was a randomized crossover pilot study in 19 preterm infants with gestational age between 28 and 34weeks. The diaper change procedure was done twice in each infant, once during skin-to-skin contact, and once in incubator or bed with the mother present. Outcome measuresDuring diaper change heart rate (HR), peripheral oxygen saturation (SpO2), and changes in skin conductance (SC) peaks per sec, using the Skin Conductance Algesimeter (SCA), were registered. ResultsThe mean SC peaks/sec increased/decreased significantly under/after change of diapers which thereby underpins that this is a stressful procedure for the preterm infant.Skin-to-skin contact (SSC) entails significantly lower stress levels (p<0.05) compared to diaper changed in an incubator/bed measured by the SCA. ConclusionsDiaper change is a stressful procedure for preterm infants and may be ameliorated by skin-to-skin contact.

Effects of Skin-to-Skin Contact on Autonomic Pain Responses in Preterm Infants

The purpose of this randomized crossover trial was to determine the effects on autonomic responses in preterm infants of longer Kangaroo Care (30 minutes, KC30) and shorter KC (15 minutes, KC15) before and throughout heel stick compared with incubator care (IC). Beat-to-beat heart rate (HR) and spectral power analysis of heart rate variability, low frequency power (LF), high frequency power (HF), and LF/HF ratio were measured in 26 infants. HR changes from Baseline to Heel Stick were significantly less in KC30 and KC15 than in IC, and more infants had HR decrease in IC than in 2 KC conditions. In IC, LF and HF significantly increased from Baseline to Heel Stick and dropped from Heel Stick to Recovery; in 2 KC conditions, no changes across study phases were found. During Heel Stick, LF and HF were significantly higher in IC than in KC30. In all 3 conditions, LF/HF ratio decreased from Baseline to Heel Stick and increased to Recovery; no differences were found between IC and two KC conditions. Both longer and shorter KC before and throughout heel stick can stabilize HR response in preterm infants, and longer KC significantly affected infants’ sympathetic and parasympathetic responses during heel stick compared with incubator care. PerspectiveThis study showed that KC has a significant effect on reducing autonomic pain responses in preterm infants. The findings support that KC is a safe and effective pain intervention in the neonatal intensive care unit.

Kangaroo Care and Behavioral and Physiologic Pain Responses in Very-Low-Birth-Weight Twins: A Case Study

The purpose of this case study was to describe pain responses in three study conditions: longer (30 minutes) kangaroo care (KC) before and throughout heel stick (KC30), shorter (15 minutes) KC before and throughout heel stick (KC15), and incubator care throughout heel stick (IC) in 28-week gestational age twins. Pain responses were measured by crying time, Preterm Infant Pain Profile (PIPP), and heart rate variability indexes, including low-frequency power (LF, representing sympathetic activity), high-frequency power (HF, parasympathetic activity), and LF/HF ratio (sympathetic-parasympathetic balance). Both twins cried more and had higher PIPP pain scores and tachycardia during heel stick in the IC condition. Infant B had an incident of apnea and tachycardia by the end of the heel stick and a bradycardia episode during recovery in the IC condition. The twins had lower LF/HF ratios (better autonomic nervous system balance) during recovery in both longer and shorter KC conditions compared with the IC condition. Infant B had difficulty returning to LF/HF ratio baseline level after the painful procedure in the IC condition. These data suggest that both longer and shorter KC before and throughout painful procedures can be helpful in reducing behavioral and physiologic pain responses in preterm infants.

Randomized Crossover Trial of Kangaroo Care to Reduce Biobehavioral Pain Responses in Preterm Infants: A Pilot Study

Kangaroo care (KC), skin-to-skin contact between mother and infant, is a promising method for blunting pain responses. This crossover pilot tested KC effects on biobehavioral responses to heel stick in preterm infants (30-32 weeks' gestational age, 2-9 days old) measured by Premature Infant Pain Profile (PIPP) and salivary and serum cortisol. Mother-infant dyads were randomly assigned to KC heel stick (KCH) first or incubator heel stick (IH) first. Study 1 (80-min study, N = 18) tested the effect of 80 min of KC before and throughout the heel stick procedure versus incubator care. Study 2 (30-min study, N = 10) tested 30 min of KC before and throughout the heel stick versus incubator care. KCH and IH began during a premeasurement phase and continued through four data collection phases: baseline, heel warming, heel stick, and recovery. PIPP responses were measured every 30 s during data collection; salivary cortisol was measured at the end of baseline and recovery; and serum cortisol was measured during heel stick. Study 1 showed no differences between KCH and IH. Study 2 showed lower PIPP scores at four time points during recovery (p < .05 to p < .001), lower salivary cortisol at the end of recovery (p < .05), and lower serum cortisol during heel stick for the KCH condition (p < .05) as well as clinically lower PIPP scores in the KCH condition during heel stick. Thirty minutes of KC before and throughout the heel stick reduced biobehavioral responses to pain in preterm infants.

1168 Contextual Factors Influencing Pain Response to Heel Stick Procedure in Preterm Infants: What Do We Know? a Systematic Review

Background: Major efforts to develop objective measurement tools for neonatal pain assessment have been made. However, the challenge of measuring pain in neonates remains, suggesting that contextual factors (CFs) might alter pain response in neonates. Although the role of CFs is increasingly discussed as crucial for pain assessment, they are not well described in the literature and barely considered in the clinical setting. Aim: To explore the impact of CFs on pain response in preterm infants. Method: Literature search was undertaken considering the period from 1990-2009. Studies reporting about the relation between one or more CFs and pain response in preterm infants during heel stick procedure were considered. Results: 23 studies were included. The studies varied highly related to the design, sample, analysis procedures, and examined variables. Six categories of CFs emerged: Age, pain exposure, health status, therapeutic interventions, behavioral status, and demographic factors, indicating that some of the CFs might have an effect on pain response in preterms. However, none of the CFs was consistently related to pain response as evidenced by contradictory findings. Inconsistency between behavioral and physiological pain response related to CFs further aggravates accurate conclusions. Conclusion: This review indicates a possible influence of some CFs on pain response. However, the results remain inconclusive, which is particularly due to the heterogeneity of the studies. CFs need further investigations in order to get more evidence regarding the magnitude of their effect on pain response. Further evidence has the potential to contribute to achieve another level of measurement of this complex phenomenon.

Comparison of Pain During Two Methods of Urine Collection in Preterm Infants

Suprapubic aspiration (SPA) and urine catheterization (UC) are performed frequently in preterm neonates to rule out urinary tract infection; however, a comparison of the pain caused by both procedures has not been made previously. To compare pain responses in preterm infants who are undergoing urine collection by using SPA versus UC. Prospective, single-blind, randomized clinical trial was conducted in 2 NICUs. Preterm infants who required urine samples for microbiologic analysis were randomly assigned to undergo either SPA or UC. The infants' facial and physiologic responses were videotaped during the procedure and later scored by a research assistant who was blind to the method of urine collection. The primary outcome measure was facial-grimacing during the procedure, which was assessed by measuring the percentage of time the infants displayed brow-bulging. Secondary outcomes included changes in heart rate (beats per minute), oxygen saturation (%), and procedural success rate. Forty-eight preterm infants participated. Characteristics did not differ (P > .05) between groups. The mean (SD) percent brow-bulging score was higher in the SPA group than in the UC group (67% [34] vs 42% [38]; P = .02). Heart rate and oxygen saturation did not differ (P = .50 and .74, respectively). The procedure-success rate, although lower in the SPA group, was not statistically different (60% vs 78%; P = .17). SPA was more painful than UC, as assessed by brow-bulging, and had a tendency to be associated with a higher rate of procedure failure. These findings should be taken into consideration when choosing between these 2 procedures for preterm infants who undergo urine sampling.

Variability in pain response to a non‐pharmacological intervention across repeated routine pain exposure in preterm infants: a feasibility study

To explore the variability in pain response in preterm infants across time who received sucrose during routine heel stick. Single group, exploratory repeated measures design. Two tertiary level neonatal intensive care units (NICU) in Switzerland. Nine preterm infants born between 28 2/7 and 31 4/7 weeks of gestation during their first 14 days of life. Pain was assessed by the Bernese Pain Scale for Neonates (BPSN), the Premature Infant Pain Profile (PIPP) and the Visual Analogue Scale (VAS). Salivary cortisol was analysed. 72-94% of the variability was within-subject variability, indicating inconsistency of pain responses across the 5 heel sticks. Interrater agreement was highest during heel sticks 1-3 and decreased during heel stick 4 and 5, indicating a possible alteration of pain patterns. No significant differences in the amount of cortisol could be detected before and after the heel sticks (p = 0.55), indicating no stress-induced peak after the painful intervention. However, a general gradual decrease of cortisol levels across time could be detected. A high variability in pain response among preterm neonates across time could be described. Consistency of cortisol levels before and after the heel sticks could indicate the effectiveness of sucrose across time.

Is It Painful or Not?

To evaluate the ability of the Behavioral Indicators of Infant Pain (BIIP) scale to discriminate between skin-breaking and nonskin breaking procedures, and to identify sensitized pain responses in preterm infants in the neonatal intensive care unit (NICU). Sixty-nine infants born between 24 and 32 weeks gestational age were assessed at 32 weeks postconceptional age during blood collection on one day (procedure A), and then on another day during blood collection preceded by a diaper change (procedure B). Procedure order was randomized. Outcome measures were changes in BIIP coded from continuous bedside video recordings and changes in heart rate (HR). During blood collection (procedure A), BIIP scores (P<0.0001) and mean HR (P<0.0001) were higher than during the diaper change and higher when the infants had had a preceding diaper change (procedure B vs. procedure A) (P<0.03). HR changed from baseline to the stressors for each procedure. No differences in mean HR were observed during Lance phase between the procedure A and the B blood collection; however, HR remained elevated significantly during the Recovery phase when blood collection was preceded by the diaper change (P<0.03). The BIIP scale is reliable, accurate, and valid assessment for measuring acute pain in preterm infants in the NICU. This assessment combines the relatively most specific, anatomically based, theoretically derived indicators; and it allows evaluation of behavioral and physiologic pain responses separately.

Analgesia in preterm newborns: the comparative effects of sucrose and glucose

The aim of this study was to evaluate the effectiveness of different oral carbohydrate solutions for alleviation of pain in healthy preterm babies. Thirty-one preterm infants who were having blood drawn by heel prick were given 2 ml of solution A (20% sucrose), solution B (20% glucose) or solution C (placebo, sterile water) into the mouth, 2 min before lancing. Behavioural responses to this painful stimulus were measured by duration of crying and facial expressions (Neonatal Facial Coding System, NFCS) and physiological responses were measured by heart rate (HR), respiratory rate (RR), and oxygen saturation changes (SaO(2)). Infants had a mean birth weight (+/-SD) of 1,401 g (406), gestational age of 30.5 weeks (2.7); at the time of the procedure the postmenstrual age was 32.3 weeks (1.5). There was no significant difference in the time spent squeezing the heel between the three groups (P = 0.669). After the heel prick of both the sucrose and glucose groups the duration of first cry and total crying time was significantly reduced (P = 0.005 and P = 0.007). When the babies received placebo they showed a significantly higher NFCS score at 4 and 5 min after the heel prick (P = 0.009 and 0.046 respectively). Following painful stimulus HR increased significantly in the first 3 min compared with baseline, and at the first minute the mean of the HR was found to be significantly higher in the placebo group than in the sucrose and glucose groups (P = 0.007). We concluded that both sucrose and glucose administered orally before a heel prick reduce the pain response in preterm infants.

Prior leg massage decreases pain responses to heel stick in preterm babies

Leg massage could inhibit the transmission of pain by 'closing the gate' or by activating the endogenous opioid pathway to decrease nociceptive transmission of pain associated with heel stick. The aim of this study is to determine the effects of massage therapy prior to heel stick on responses assessed by the Neonatal Infant Pain Scale (NIPS) (primary outcome), heart rate, respiratory rate and oxygen saturation (secondary outcomes) in infants who required a heel stick for blood sampling. This randomised, double-blind, crossover trial with infants from 1 to 7 days post birth excluded those with prior surgery, septicaemia, current assisted ventilation or an analgesic within 48 h. After informed consent, 13 infants received a 2-min massage of the ipsilateral leg prior to heel stick on the first study sampling and no massage on the next sampling 2-7 days later and 10 infants had the reverse order. The bedside nurse, blinded to the intervention, measured NIPS, heart rate, respiratory rate, and oxygen saturation prior to massage, after massage, and 5 min after heel stick. Serum cortisol was measured with the blood sampling. In 23 infants (birthweight 795-2507 g), there were no adverse physiologic effects of massage. After heel stick, NIPS (P < 0.001) and heart rate (P = 0.03) were increased in the no-massage group compared with the massage group. Respiratory rate, oxygen saturation and serum cortisol were not significantly different. Gentle massage of the leg prior to heel stick is safe and decreases pain responses in preterm infants.

Stressful procedures in the nicu

Major efforts to develop objective measurement tools for neonatal pain assessment have been made. However, the challenge of measuring pain in neonates remains suggesting that contextual factors (cFs) might alter their responses to pain. Although the role of cFs is increasingly discussed as crucial for pain assessment, they are not well described in the literature and are rarely considered in the clinical setting despite their importance.To systematically examine studies investigating the impact of cFs on pain response in preterm infants.A literature search was undertaken for the period from 1990 to 2009. Studies reporting the relation between one or more cFs and pain response in preterm infants during a heelstick procedure were considered for inclusion.Twenty-three studies satisfied inclusion criteria. The studies varied relative to their design, sample, analysis procedures, and variables examined. Six categories of cFs emerged: age, pain exposure, health status, therapeutic interventions, behavioral status, and demographic factors. The examined cFs varied in the strength of their association with pain response, although none were invariably related, as evidenced by contradictory findings. In some cases the inconsistencies appeared attributable to methodological limitations in studies. Behavioral and physiological pain responses were not always in agreement as would be expected.This review supports the influence of some cFs on pain response. However, the results remain inconclusive which may be, in part, related to the heterogeneity of the studies. Contextual factors need further investigation for a better understanding of the magnitude of their effect on pain response.