Pain assessment in the newborn: Translation and pilot testing of N-PASS (Neonatal Pain, Agitation

and Sedation Scale)

Karen Ýr Sæmundsdóttir1, , Margrét Eyþórsdóttir1, 2 and Guðrún Kristjándóttir1, 2

1 Nursing Department University of Iceland, 2 Childrens Hospital of Landspítali University Hospital.

INTRODUCTION: Chronic pain in neonates can have permanent influence on the development of their nervous system and can among other things cause changes in their reaction to pain. Careful and correct assessment of pain in the infant and hopefully better pain relief is an important part in the care of the neonate. Neonatal Pain, Agitation and Sedation Scale (N-PASS) is a pain scale that was especially designed to assess prolonged pain, agitation and sedation in neonates. This pain scale differs from other pain scales in that it assesses prolonged or chronic pain, compared to PIPP that assesses acute procedural pain and CRIES assesses pain after surgery, and further it also assesses the infant’s agitation and sedation. The N-PASS was translated to Icelandic and pilot tested. The purpose of the study was to find out whether it is valid and reliable in Icelandic and to assess the feasibility of using it in clinical settings.

MATERIAL AND METHODS: N-PASS is a multidimensional instrument that uses five behavioral and physiological components that research has shown to indicate pain. There are four behavioral components, crying or irritation, facial expression, behavior and tonus of extremities, and the fifth component is changes in any of these vital signs, heart rate, respiration rate, blood pressure or oxygen saturation. These components are rated on a five -point scale (-2, -1, 0, 1, 2 and +1 added if the gestation age is 30 weeks or lower at the time of assessment) according to the infants’ behavior. The negative numbers are the sedation part of the scale and the positive numbers are the pain/irritation part of the scale. A total score of three and over is considered to be indication of pain and to call for intervention. The research design was descriptive quantitative and the sample was a convenience sample. The sample consisted of 22 neonates that had been admitted to the NICU of the Children’s Hospital of Iceland University Hospital in Reykjavik, Iceland, nine premature infants and thirteen mature infants, in total fourteen boys and eight girls. The final sample consisted of 16 infants, 7 premature and 9 mature infants, as all measurements could not be completed in six of the infants. The criterion for participation was that the infant was to undergo a painful intervention solely for medical reasons. Also the infant had to be connected to a monitor showing heart rate and oxygen saturation. Each infant was assessed in three different situations, neutral (infant sleeping or quiet awake), situation seen as being disturbing but not painful (change of diaper or measuring temperature or other similar situations) and a painful situation (heel prick, insertion of I.V. needle and other painful situations). Paired T- test was used to compare situations and measure whether there was a significant difference between those three situations, as well as whether there was any difference between the premature and mature infants. Each assessment was made by the researcher, and on five occasions the infants also were assessed by a nurse on the unit and their results were also compared to the researchers.

FINDINGS: Paired T-tests show that here is a significant difference between neutral situation and disturbing situation (t=-5,74 p=0,000), neutral situation and painful situation (t=-6,07, p=0,000) but there is no significant difference between disturbing situation and painful situation (t=-1,566, p=0,138). To explore further, paired T-tests were carried out for all five components of the scale in these two situations and there was significant difference in facial expression between disturbing and painful situations (t=-2.046, p=0.029), but no difference in the other four components. Table 1 shows the situations that were seen as disturbing and the painful situations. There was no significant difference between premature and mature infants in all three situations, but the mature infants had higher mean scores in all situations. Table 2 and figure 1 show the mean scores for the premature and mature infants in all three situations. There was no significant difference between the researcher and the nurses on the unit but the nurses’ mean scores were lower in all situations (see figure 2). Reliability test indicates that the N-PASS pain scale is reliable in all three situations. In neutral situation Chronbach's alpha is 0,360, in the disturbing situation Chronbach's alpha is 0,765 and in the painful situation Chronbach's alpha is 0,794.

References:

Anand, K. J. S. (2000). Effects of perinatal pain and stress. Progress in Brain Research, 122, 117-129. Hummel, P., Lawlor-Klean, P. og Weiss, M.G. (2009). Validity and reliability of the N-PASS assessment tool with acute pain. Journal of perinatology (article in press). Mitchell, A. Og Boss, B.J. (2002). Adverse effects of pain on the nervous systems of newborns and young children: A review of the literature. The Journal of Neuroscience Nursing: Journal of the American Association of Neuroscience Nurses, 34 (5), 228-236. Qiu, J. (2006). Infant pain: Does it hurt? Nature, 444 (7116), 143-145.

Figure 1 Comparison of N-PASS means between premature and mature infants in three separate

situations of intervention N=16

Table 1 Type and number of interventions in the three different situations N=16

Figure 2 N-PASS means between the researcher and the RN on the Unit in five separate cases by type of intervention. CONCLUSIONS:

The results indicate that N-PASS in the Icelandic translation is valid in all three situations and reliable in the disturbing and the painful situations. There seems to be difficulty in distinguishing between the disturbing and the painful situations, but when the two situations are compared some of the situations classified as disturbing could just as well be classified as somewhat painful. Further distinction is needed between these two before the N-PASS pain scale can be used in a clinical setting. For some time sucrose has been used when blood samples are drawn either by heel prick or veins, the researcher does not mention this except in one case. Further research is needed with a larger sample.

0 0,5

1 1,5

2 2,5

3 3,5

4 4,5

Neutral situation

Disturbing situation

Painful situation

Karen Ýr Nurse on unit

0

1

2

3

4

5

6

Neutral situation

Disturbing situation

Painful situation

Premature infants Mature infants

Disturbing interventions n Painful interventions n

Physical examination 1 Insertion of I.V. venflon or drawing blood for testing 8

Diaper changing 5 Heel prick 3 Measuring blood pressure 2 I.M. injection 2 Physiotherapy 1 Tracheal tube suction 1 Measuring temperature 2 Other suction 2 Alteration in positioning in incubator 4 Measuring length 1 TOTAL OBSERVATIONS 16 TOTAL OBSERVATIONS 16

 Intervention type Birth age N Mean Std. Deviation

Neutral situation Preterm 7 .14 .378 Fullterm 9 .11 .333

Disturbing situation Preterm 7 2.43 1.512

Fullterm 9 3.22 2.048

Painful situation Preterm 7 3.14 2.545 Fullterm 9 4.89 2.759

Table 2 Distribution of mean N-PASS scores by birth age N=16