1. Introduction
It is difficult to provide healthcare without causing pain and discomfort. Procedural pain, also known as care-induced pain, is defined as an unpleasant sensory and emotional experience caused by caregivers or treatment in circumstances where its occurrence is foreseeable and can be prevented by appropriate measures [1] . Contrary to the dictum that children do not experience pain, it has been shown that from the first hours of life, neonates are likely to experience acute pain due to obstetric trauma, and untimely maneuvers, but especially during care procedures such as blood sampling or aspiration of any kind [2] .
However, pain assessment in the newborn remains a challenge because of the lack of language acquisition at this age. As a result, pain is not expressed in words, but rather through attitudes and behavioral changes that are easily overlooked. The neglect of repeated acute pain episodes develops dynamically, with biochemical and electrophysiological changes that can lead in the short term to hyperalgesia with a reduction in the pain tolerance threshold [3] . Similarly, the fact that pain in the neonatal period occurs in a developing brain with great plasticity has the potential to alter the normal development of somatosensory circuits and pain pathways.
In the long term, this leads to a plethora of neurological disorders, including cognitive impairment, learning disabilities, attention deficit, behavioral problems, and motor disorders [4] .
Proper assessment of care-induced pain is the basis for effective screening and appropriate management [5] . It should be carried out using a validated scale, depending on the patient’s age and context. Unlike adults and older communicating children, for whom self-assessment is preferred, there can only be a hetero-assessment in neonates [2] .
Although tools for assessing acute pain in newborns exist, their use in current practice reveals several shortcomings. These include inappropriate description of pain intensity and inadequate use of analgesics in relation to pain severity [6] [7] [8] [9] .
In Cameroon, improvements in neonatology services have led to better care for full-term and premature newborns over the years [10] , resulting in a reduction in the neonatal mortality rate [11] .
As a result, hospitalizations in neonatology departments are more frequent, and by extension more painful healthcare procedures are carried out. This article looks at the assessment of acute pain experienced by hospitalized neonates during healthcare procedures.
2. Material and Methods
We conducted a cross sectional study with prospective data collection. It took place in the neonatology units of the Mother and Child Centre of the Chantal Biya’s Foundation (MCC-CFB), the Yaoundé Gynaeco-obstetric and Pediatric Hospital (YGOPH), and the Essos Hospital Center (EHC). These facilities were chosen because they are leading pediatric teaching hospitals in Cameroon.
The study was observational and lasted for eight months, from October 2022 to May 2023. It targeted all neonates who were hospitalized in the neonatology units of the three selected hospitals. After obtaining parental consent, all hospitalized neonates who were awake and not crying prior to onset of the healthcare procedure were enrolled.
Patients were examined firstly during the care procedure and secondly two minutes after. Pain was assessed and graded using the DAN scale. The DAN scale is a behavioral scale used to score acute pain in term and preterm neonates. This tool evaluates three items: facial expressions, limb movements and vocal expression. Pain is scored from 0 to 10 where 0 represents no pain and 10 the maximum pain.
The sociodemographic and clinical data of each subject was recorded in an anonymous data collection form. The collected data were analyzed using SPSS 23.0 software. The one-factor ANOVA test was used to analyze the variance of pain intensity according to the type of procedure (statistical significance was set at 0.05). The significance of the difference in mean DAN scores according to the type of procedure was confirmed using the TUKEY test.
3. Results
3.1. Hospital Prevalence of Neonatal Procedural Pain
During the study period, 137 of the 161 neonates evaluated had experienced pain during care. The hospital prevalence of care-induced pain was 85%.
3.2. Sociodemographic Characteristics
The median age of the neonates was 5 days, with a range of 1 to 49 days. Males accounted for the majority of cases (60.9%), with a sex ratio of 1.56 (Table 1).
3.3. Perinatal Features of Neonates
3.3.1. Mode of Delivery and Adjusted Gestational Age
Most of the new-borns, 67.1%, were born pervaginallly.
The median adjusted gestational age at birth was 37 weeks, with a range of 26 to 38 weeks (Table 2).
![]()
Table 1. Population distribution based on sociodemographic characteristics.
![]()
Table 2. Population distribution based on mode of delivery and adjusted gestational age.
3.3.2. Neonatal Anthropometric Measurements
The measurements were taken on the day care was provided. The mean birth weight was 2694.1 ± 1023 grams, ranging from 600 to 5000 grams. The mean height was 47.5 ± 5.5 cm, ranging from 32 to 58 cm. Of the patients, 55.4% were eutrophic, 33.5% were hypotrophic, and 10.6% were macrosomic (Table 3).
3.4. Diagnosis on Admission
Neonatal sepsis was the main diagnosis on admission (96.9%) (Table 4).
3.5. Care Procedures Performed
At the time of the survey, the two main procedures performed were blood sampling (94.4%) and the insertion of peripheral venous lines (93.8%). These procedures were performed once a day in 90.7% of cases (see Table 5).
3.6. Evaluation of Neonatal Care-Induced Pain
3.6.1. Evaluation of Global Care-Induced Pain
Procedural pain experiences were dominated by the insertion of peripheral venous lines, which accounted for 62.1% of cases. Before care, pain was present in 8.7% of patients and was of mild intensity. During the procedure, pain was observed in all subjects in the sample and was severe in 83.9% of cases. Two minutes after the procedure, pain was present in 26.1% of neonates and was of mild intensity. The mean duration of pain was 64.1 ± 26.1 seconds, ranging from 15 to 124 seconds depending on the type of procedure (Table 6).
3.6.2. Evaluation of Care-Induced Pain According to Procedure
Median DAN scores varied according to the type of procedure (Table 7). They were highest for lumbar punctures (DAN = 10). They were 9 for peripheral venous access line and blood sampling. The lowest median (DAN = 8) was for intravenous injections.
![]()
Table 3. Population distribution based on neonatal anthropometric measurements.
![]()
Table 5. Healthcare procedures performed.
![]()
Table 6. Assessment of procedural pain.
![]()
Table 7. DAN score during the procedure according to the different types of care.
3.6.3. Correlation between Pain Intensity and Type of Procedure
1) One-factor ANOVA test
The one-factor ANOVA test showed that the DAN score varied significantly according to the type of procedure performed (p = 0.002). The procedure with the highest pain was lumbar puncture (Table 8).
2) Association between pain and type of procedure
During the procedures, the difference in mean DAN scores was significant between peripheral venous line placement and injections (p = 0.001). Similar results were observed between blood sampling and injections (p = 0.041). Venous access procedures were therefore more painful than intramuscular injections (Table 9).
3.6.4. Correlation between Duration of Pain and Type of Procedure
1) One-factor ANOVA test
The One-factor ANOVA test showed that there was a significant difference between the mean pain durations associated with each type of procedure (p < 0.001) (Table 10).
![]()
Table 9. Tukey test comparing pain during different procedures.
![]()
Table 11. Tukey test comparing pain durations during different procedures.
2) Association between duration of pain crisis and type of procedure
The mean duration of acute pain episodes was significantly greater between peripheral venous access and injections (p < 0.001). Similar results were observed between blood sampling and injections (p < 0.001) (Table 11).
4. Discussion
4.1. Hospital Prevalence
We found a hospital prevalence of acute care-induced pain of 85%. This value can be explained by the large number of painful procedures that neonates undergo during hospitalization. These results are similar to those of Carbajal et al. in France in 2008, who found a 79.7% prevalence of painful procedures during hospitalization in a neonatal unit [12] . Similarly, a Congolese series reported in 2019 that one of the main causes of neonatal pain was care-induced pain, with a hospital prevalence of 73.6% [13] . However, this prevalence varies from one study to another, depending on whether there are pre-existing protocols for the management of acute neonatal care-induced pain.
4.2. Sociodemographic Profile
The sample consisted of 161 neonates undergoing painful procedures daily. The median age was 5 days, ranging from 1 to 49 days. Age was recorded on the day of care and according to the length of hospital stay.
Males were more represented, accounting for 60.9% of cases, with a sex ratio of 1.56. However, the impact of sex on pain response has not been proven [14] .
Full-term births were more represented than preterm births, 72% and 28% respectively. These data corroborate those from the 2018 National Demographic Health Survey, which found that full-term newborns accounted for around 88% of live births [10] .
The weight was measured on the day of the procedure and was 2694.1 ± 1023.0 grams, ranging from 600 and 5000 grams. This result is supported by the fact that most of the newborns admitted to the hospital were full-term.
4.3. Diagnosis
Neonatal sepsis was the main cause for admission (96.9%). Neonatal sepsis is the most common cause of hospital admissions in neonatology, particularly in Cameroon, as shown by the results of a study by KedyKoum et al. in a referral hospital in Douala in 2015 [11] .
4.4. Healthcare Procedure Performed
Blood sampling and peripheral venous line insertion were the two most painful procedures performed, at 94.4% and 93.8% respectively. Most procedures were performed once a day (90.7%). These results differ from those of other European cohorts, which showed that the most painful procedures in neonates were gastric fluid sampling, pharyngeal suctioning, and skin punctures (venous and capillary sampling) [5] [15] . These differences could be explained by the severity of the diagnosis. The advanced technical facilities available in developed countries allow them to admit newborns with severe clinical conditions, and the management of these infants involves a large amount of care, ranging from resuscitation measures to various diagnostic tests.
4.5. Evaluation of Care-Induced Pain
The procedures that caused pain in neonates were, in descending order, peripheral venous line insertion, venous sampling, intramuscular injections, and lumbar puncture. There was virtually no pain before the procedure (91.3%). During the procedure, pain was observed in all cases and was severe in 83.9% of cases. Two minutes after the procedure, 36.7% of patients had pain, including 26.1% with mild pain.
The procedure with the highest pain threshold was lumbar puncture, followed by venous access procedures. In the case of lumbar puncture, the severity of pain is explained anatomically and physiologically by the proximity of the puncture site to the nerve roots emerging from the spinal cord in the subarachnoid space. As a result, when the needle reaches these very sensitive areas during the puncture, the pain is severe.
Venous access procedures are not painful per se, but in our context the use of large caliber needles, which are unsuitable for neonates, raises the pain threshold. On the other hand, the repetition of the nociceptive gesture in the search for a vein biases the assessment of pain. These results are concordant with those of a Moroccan series from 2011, which found that the severity of the same procedures was 71% during the procedure and 22% after the procedure [16] .
The average duration of acute pain episodes was significantly longer for peripheral venous line insertion than for injections. Similar results were observed between blood sampling and injections. These findings may be explained by the way the procedure is performed. When a peripheral venous line is inserted, the difficulty in gaining access to the vein due to age-inappropriate equipment leads to many repeated punctures, thereby increasing the duration of the pain episode. The same explanation applies to blood sampling, the duration of which depended on the quantity of blood required for the examination.
5. Conclusion
Painful procedures are very common during neonatal hospitalization. The most common nociceptive healthcare procedures were peripheral venous line insertion, blood sampling, injections, and lumbar puncture. The intensity of acute care-induced pain was predominantly severe. The most painful procedure was lumbar puncture. Venous access procedures caused severe pain and lasted longer. The recurrence of neonatal procedural pain in our context suggests the need to harmonize pain management protocols for neonates.
Acknowledgements
Meguieze C.A. designed the research protocol. Bidias R. collected and analyzed the data obtained. Nseme E.E. and Koki N.P.O. corrected the research project and supervised the work. All authors participated in writing the research article.