Nigerian Postgraduate Medical Journal

ORIGINAL ARTICLE
Year
: 2022  |  Volume : 29  |  Issue : 4  |  Page : 310--316

Evaluation of the effect of nutritive versus non-nutritive pacifiers as adjuncts to local anaesthesia in male neonatal circumcision using the plastibell technique – A prospective randomised controlled study


Chibuike George Ihediwa1, Christopher O Bode2, Felix M Alakaloko1, Olumide A Elebute2, Justina O Seyi-Olajide1, Oluwaseun Abiola Ladipo-Ajayi1, Adesoji O Ademuyiwa2,  
1 Department of Surgery, Paediatric Surgery Unit, Lagos University Teaching Hospital, Lagos, Nigeria
2 Department of Surgery, Paediatric Surgery Unit, Lagos University Teaching Hospital; Department of Surgery, College of Medicine, University of Lagos, Lagos, Nigeria

Correspondence Address:
Chibuike George Ihediwa
Department of Surgery, Paediatric Surgery Unit, Lagos University Teaching Hospital, Lagos
Nigeria

Abstract

Background: Male circumcision is the most common surgical procedure worldwide and is often carried out for religious, cultural, medical and public health reasons. It is commonly performed during the neonatal period. Many studies have now shown that pain is a common intra- and post-operative complication. To ensure proper analgesia during the procedure, many surgeons opt for the use of pacifiers as an adjunct to anaesthesia during neonatal circumcision. The aim of this study is to compare nutritive pacifiers (NPs) versus non-NPs (NNPs) as adjuncts to local anaesthesia in male neonatal circumcision using the Plastibell technique. Methods: A prospective randomised controlled study was carried out between October 2019 and March 2020. A total of 100 neonates were circumcised using the Plastibell technique and randomised into NP (Group A, n = 33), NNP (Group B, n = 33) and controls (Group C, n = 34), respectively. The differences in pain scores using the Neonatal Infant Pain Scale, total crying time and heart rate during circumcision were recorded and assessed. Results: The age of participants ranged from 5 to 28 days and the weight ranged from 2.5 to 5.0 kg. The overall mean age, birth weight and current weight of the participants were 15.5 ± 6.1 days, 3.4 ± 0.4 kg and 3.5 ± 0.6 kg, respectively. The control group had the highest average pain score of 5.5 (4.5–5.8) compared to the intervention groups with median pain score (NP: 3.3 [1.3–4.3] and (NNP: 4.3 [3.1–5.1], respectively). NPs had significantly lower pain scores (P = 0.023) and reduced total crying time (P = 0.019) at all stages of the circumcision compared to those given NNPs and controls. Conclusion: This study showed that NPs were superior to NNPs in providing additional pain control during male neonatal circumcision.



How to cite this article:
Ihediwa CG, Bode CO, Alakaloko FM, Elebute OA, Seyi-Olajide JO, Ladipo-Ajayi OA, Ademuyiwa AO. Evaluation of the effect of nutritive versus non-nutritive pacifiers as adjuncts to local anaesthesia in male neonatal circumcision using the plastibell technique – A prospective randomised controlled study.Niger Postgrad Med J 2022;29:310-316


How to cite this URL:
Ihediwa CG, Bode CO, Alakaloko FM, Elebute OA, Seyi-Olajide JO, Ladipo-Ajayi OA, Ademuyiwa AO. Evaluation of the effect of nutritive versus non-nutritive pacifiers as adjuncts to local anaesthesia in male neonatal circumcision using the plastibell technique – A prospective randomised controlled study. Niger Postgrad Med J [serial online] 2022 [cited 2022 Dec 6 ];29:310-316
Available from: https://www.npmj.org/text.asp?2022/29/4/310/359761


Full Text



 Introduction



Circumcision is a common practice worldwide. Currently, male circumcision is the most prevalent surgical procedure worldwide; an average of one in every three men worldwide is circumcised.[1] In several parts of West Africa, including Nigeria, male circumcision is routinely performed in the neonatal period. In some other cultures and uncommon instances, male circumcision can be done outside the neonatal period.[2]

There are several reasons for male circumcision worldwide: these include cultural reasons (most common reason for circumcision worldwide), religious, social and therapeutic reasons (including treatment for pathologies and prevention of disease transmission, e. g., HIV).[3],[4]

Several forms of anaesthesia are available for newborn circumcision. Penile blocks with plain lidocaine and topical application of eutectic mixture of local anaesthetic cream have been used in this regard. In an attempt to optimise pain control, other forms of analgesia are also utilised in addition to the preferred anaesthetic method.[5]

Neonatal male circumcision is currently performed using some form of analgesia for pain control in a combination of pharmacological and non-pharmacological methods. Various adjunctive measures have been employed to minimise distress experienced by these neonates during circumcision. These include the use of nutritive and non-nutritive sucking delivered essentially via pacifiers.[6] This study provided a comparison between nutritive pacifiers (NPs) and non-NPs (NNPs) and their suitability as effective adjuncts to anaesthesia in neonatal circumcision.

 Methods



This was a prospective, randomised controlled, hospital-based study to compare the efficacy of NPs versus NNPs as an adjunct for neonatal male circumcision using the Plastibell device at two hospitals in Lagos over a 6-month period between October 2019 and March 2020. Ethical approval was obtained from the Human Research Ethics Committee (HREC) of the Lagos University Teaching Hospital, Idi-Araba, Lagos State (Approval Date: June 18, 2019. APPROVAL NUMBER: ADM/DCST/HREC/APP/2516).

The study was not blinded as blinding the mothers of participants (neonates) did not provide any benefit in terms of elimination of bias in response to the effects of the pacifiers used on participants. The researchers were also not blinded as they were directly involved in the care of the participants from admission, pre-, intra- and post-operative phases of care as well as discharge.

All male neonates presenting for circumcision at the Paediatric Surgical Unit of the Department of Surgery who met the inclusion criteria and whose parents consented to the study were recruited. All the consultants, residents and nurses of the units involved in the patient's care were informed of the project.

Sample size calculation

The level of significance (α) and the power of the study (1−β) were set at 5% and 80%, respectively. The sample size was determined for each of the study populations using the formula for comparing two means. However, a Bonferroni correction (α/T) was done to adjust the significance level for multiple comparisons of three arms: control, NP and NNP groups.

[INLINE:1]

where

N = Sample size for each arm of the intervention groups

σ = Assumed SD of each group (assumed to be equal for the groups) = 0.8[7]

Zα/T = Standard normal deviate corresponding to a significance of 0.0167 = 2.39 (α=0.05, T = 3)

Zpwr = Standard normal deviate corresponding to a statistical power of 0.80 = 0.84

D = Minimum expected difference between the two means = (0.45, 1.12)

[INLINE:2]

Assuming 10% attrition rate: 30 + 3= 33.

As such, 33 patients were allocated to each of the three groups.

Inclusion criteria

All healthy male neonates who presented to the Paediatric Surgery Units of the two hospitals in the study for circumcision with gestational age at birth ≥37 weeks after written consent of the parents or guardians were included in the study.

Exclusion criteria

Sick neonates, all neonates with personal or family history suggestive of bleeding disorders, patients with hypospadias and epispadias, neonates with groin infections as well as patients whose caregivers declined consent were excluded from the study.

Sampling method

The patients were assigned to three groups; Group A consisted of neonates who received a dextrose pacifier administered via a plastic dummy with a compartment into which a small 5 x 5 cm strip of sterile gauze soaked in 10 ml of 10% dextrose saline was enclosed and subsequently inserted orally then strapped in place for the neonate to suckle on during the procedure (NP), Group B consisted of neonates who used a plain plastic dummy pacifier inserted orally (NNP), while Group C constituted the control group who were given no pacifiers. Random computer-generated numbers were used to randomise participants to the various arms of the study without replacement using the Microsoft Excel software.

Data collection instrument

The following data were obtained using a study pro forma: bio-data, indication for circumcision, the timing of procedure (onset, end and duration) and heart rate at set stages of the procedure, total crying time and pain assessment using the Neonatal Infant Pain Scale (NIPS)

Pre-operative protocol

After obtaining written informed consent from the parents, focused clinical history taking and physical examination were carried out to rule out a family history of bleeding diatheses as well as clinical stigmata of bleeding diatheses. Patients were not fasted preoperatively and were allowed to be with the mothers until shortly before the procedure. An appropriate-sized Plastibell ring, plastic pacifiers, 10% dextrose water solution and a sterile circumcision set for the procedure were provided. The pacifiers were inserted into the mouth 2 min before the commencement of the procedure and held in place with a plaster strapping in those randomised to receive them.

Intra-operative protocol

The patients were transferred to the theatre covered to ensure warmth. They were subsequently restrained using a 'circumstraint' where available or held in supine lithotomy by a theatre assistant. The perineum was cleansed with 1% chlorhexidine gluconate (Savlon©, Johnson & Johnson) solution and sterile drapes applied. Each neonate received a dorsal penile nerve block (DPNB) using plain 2% lidocaine solution at a dose of 3 mg/kg administered at 2 and 10'O clock positions on the dorsal aspect of the root of the penis. The choice of DPNB was informed by the unit protocol for circumcision at the Lagos University Teaching Hospital.

The prepuce was initially held taut at its tip using two straight haemostats. Following this, a curved haemostat was subsequently introduced to break down preputial adhesions circumferentially where applicable. This was followed by digital retraction of the prepuce over the glans to remove smegma using a 1% chlorhexidine gluconate (Savlon©, Johnson & Johnson) solution. The retracted prepuce was subsequently returned over the glans. A dorsal slit was subsequently made using a straight haemostat and scissors to aid the admittance of the Plastibell ring. Holding the ring in place, the Plastibell cord was securely fastened over the prepuce in the appropriate groove on the bell and excess preputial skin trimmed off flush with the bell.

Residents of the unit were trained to use the NIPS and subsequently deployed to collect pain score data at various stages of the procedure while the circumcision was performed. A stopwatch was used to determine the total crying time during the procedure. This was monitored and recorded by a separate assistant. The heart rate before, during and immediately after the procedure was recorded by a theatre nursing staff with the aid of a transcutaneous oxygen saturation machine attached to the hallux of the neonate throughout the procedure. The circumcision procedure was carried out by the doctors in the unit.

Post-operative protocol

Each patient was observed for a minimum of 1 h before discharge. All mothers were encouraged to breastfeed their babies soon after the procedure to minimise crying. Oral paracetamol 10–15 mg/kg body weight every 6–8 h for 3 days was prescribed for post-operative analgesia. All parents were instructed to present to the emergency room if the significant complication of excessive haemorrhage occurs. Patients were seen in the outpatient clinic on the 5th day post-operative to assess the surgical site and identify early complications. For those patients with rings that did not fall, they were reassured, and mothers asked to present for removal if it had not fallen by the 14th day post-operative.

Statistical analysis

Data entry and analysis were done using the Statistical Package for the Social Sciences Statistics IBM version 23 (Armonk, New York, USA). Tables and charts were used to present the data as appropriate. Categorical variables were expressed as frequencies and percentages. Chi-square and Fisher's exact tests were done to compare categorical variables between the groups. Numerical variables were summarised using means and standard deviation. Analysis of variance (ANOVA) was used in comparing differences in means of pain score between the three groups, and a post hoc test was done for significant results. Pain score was presented a median and interquartile range, and the non-parametric Kruskal–Wallis H test was done to compare pain score across categories of patients. A Dunn's mean rank pairwise comparison was done to establish a significant difference in pain score rank between individual categories of participants. All analysis was conducted with a 95% confidence level and 0.05 level of significance.

 Results



A total of 100 neonates were recruited.

Sociodemographic characteristics of participants

The age of participants ranged from 5 to 28 days and the weight ranged from 2.5 to 5.0 kg. The overall mean age, birth weight and current weight of the participants were 15.5 ± 6.1 days, 3.4 ± 0.4 kg and 3.5 ± 0.6 kg, respectively. There was no significant difference in mean age, birth weight and current weight of participants when compared across categories [Table 1].{Table 1}

Comparison of pain scores in groups of participants

The median interquartile range (IQR) of the average pain score throughout the procedure as depicted in [Figure 1] was highest in controls and lowest in patients given NPs (P < 0.001). At the onset of the procedure, the median pain score was significantly highest in controls when compared with other categories (P < 0.001). In the control group, the median pain score was 5.0 and the upper quartile had a pain score above 6.0. However, the median pain score was 1.0 for the other groups, and the upper quartiles had lower pain scores (2.5 and 4.5, respectively) [Table 2].{Figure 1}{Table 2}

The median pain score was significantly different (P < 0.001) between the two categories of participants at all other stages of the procedure. At the end of the procedure, the median (IQR) pain score was equal in both the controls and neonates given NNPs (6.0 [5.0–6.0]) (P = 0.693) but lower in neonates given NPs (5.0 [1.0–6.0]) [Table 2].

The pairwise comparison for pain scores between the individual groups of participants is depicted in [Table 3]. The neonates given NPs had significantly lower average pain score throughout the procedure when compared with those who were given NNP (P = 0.023) and controls (P < 0.001).{Table 3}

Except at the onset of procedure, where pain score was not significantly different between both the pacifier groups (P = 0.366), neonates given NPs had lower pain score at all stages when compared with those who were given NNP and controls. Except at the onset where pain score in neonates given NNP was significantly higher than in controls (P = 0.004), there was no significant difference in pain score between neonates given NNP and controls at subsequent stages of the procedure [Table 3].

Comparison of crying time across groups of participants

The duration of the procedure ranged from 4 min to 24 min overall. The mean duration of the procedure was highest in controls (9.5 ± 4.1 min); however, this was not significantly different from the mean duration in other categories (P = 0.242). The total crying time was highest in controls (6.6 ± 2.5 min) and lowest in patients given NPs (3.20 ± 1.88 min), and there was a significant difference (P < 0.001) in total crying time across categories of patients. Patients given NP also significantly (P < 0.001) spent the least percentage of the procedure time crying (36.96 ± 24.78%) [Table 4].{Table 4}

The pairwise comparison for crying times between the individual groups of participants is displayed in [Table 5]. The total crying time in neonates given NPs was significantly lower than in those given NNPs (P = 0.019) and also lower than in controls (P < 0.001).{Table 5}

Pairwise comparison showed that the percentage of total procedure time spent crying in neonates given NPs was significantly lower than in those given NNPs (P ≤ 0.001) and also lower than in controls (P < 0.001). However, when the percentage of procedure time during which crying occurred was compared specifically between neonates given NNP and controls, there was no significant difference (P = 0.120) [Table 5].

Comparison of heart rate across groups of participants

The mean heart rate between categories of participants is depicted in [Table 6]. The mean heart rate was highest in controls at the dorsal slit stage, prepuce excision and at the end of the procedure.{Table 6}

There was no statistically significant difference in the mean of the average heart rate throughout the procedure across categories of participants [Figure 2].{Figure 2}

 Discussion



Pain control remains a fundamental aspect of any surgical procedure as it may impact on the outcome. In the study, the impact of NPs and NNPs on pain control during circumcision was explored.

The control group had significantly increased pain scores (P < 0.001) 5.0 (1.8–6.0) at the onset of the procedure. Patients receiving interventions had pacifiers to soothe them following the pinprick of the dorsal penile nerve block, and this might have accounted for differences noted in pain scores compared to the control group. This is similar to what was obtained by South et al.[8] where in addition to DPNB, neonates given non-nutritive sucking showed a significant reduction in pain scores. Pain assessment was by the premature infant pain score in that study instead of the NIPS used in this current study.

Furthermore, neonates who had NPs had lower pain scores at all stages of the circumcision compared to those given NNPs and controls. Similarly, Akman et al.[9] also reported significantly lower pain scores (P = 0.001) in neonates given sucrose combined with a pacifier compared to the other study groups. The pain was, however, assessed during heel lancing, and the Neonatal Facial Coding System (NFCS) was used for pain assessment in their study.

When a comparison is made between the NP and NNP groups (NP-NNP), NPs led to significantly lower average pain scores (P = 0.023) throughout the procedure. This underscores the value of sweet solutions in providing analgesia during circumcision. Sucrose is the most studied sweet solution used in this regard. However, Akman et al.[9] reported that dextrose could also be used to provide similar effect while noting that it was inferior to sucrose. In this study, 10% dextrose was used as the sweet solution as it is readily available and affordable.

Neonates who received NNP had significantly lower average pain scores throughout the procedure (P < 0.010) compared to controls. However, aside from the onset of the procedure, there was no significant difference recorded between the pain scores of the control and NNP groups at the other stages of the procedure. This may suggest the oro-tactile and mechanoreceptor pathways through which NNS is believed to act might be insufficient when acting in isolation to produce significant analgesia during circumcision. The use of a sweet solution along with a plastic dummy for the neonate to suck on while undergoing circumcision engages the oro-gustatory pathway in addition to the oro-tactile pathway in producing significant analgesia. The efficacy of sucrose for use in this regard has already been established in the literature.[10],[11]

Neonates of the control group in this study cried the most (6.60 ± 2.52 min) while those who received NPs cried the least (3.20 ± 1.88 min). This difference was statistically significant across all categories of patients studied (P < 0.001). This agrees with the findings of Blass and Hoffmeyer[12] where sucrose administration led to a significant reduction in total crying time compared to water as a pacifier and the control group (P ≤ 0.05). Akman et al.[9] also recorded a significant reduction in crying time in neonates given sucrose and dextrose, respectively, followed by a pacifier. The effect of sucrose on crying time was better than that of dextrose; however, this difference was not statistically significant (P = 0.39).

In our study, when the percentage of procedure time spent crying was compared specifically between neonates given NNP and controls, there was no significant difference (P = 0.120). South et al.,[8] however, recorded a significant reduction in crying time between controls (6.3 ± 2.35 min) and neonates who were given non-nutritive sucking via a gloved finger (4.2 ± 2.6 min). This might be due to differences in the method of administering NNP. A plastic dummy was used for non-nutritive sucking in our study while a gloved finger of an assistant was used in theirs. The use of a gloved finger by South et al.[8] to provide non-nutritive sucking leads to a dynamic tactile stimulus in the neonates' mouth, thus stimulating the suck reflex and soothing the neonate. This effect is not seen with a dummy strapped in place in the neonates' oral cavity as used in our study. In addition, the pre-operative administration of oral Tylenol in addition to DPNB could have improved pain control and comfort in the neonates, thus reducing crying time in their study.

Furthermore, pairwise comparison showed that total crying time in neonates given NPs was significantly lower than in those given NNPs (P = 0.019). There is a paucity of literature directly comparing these two non-pharmacological adjuncts; however, most studies advocate a combination of both to achieve optimal results.[9],[13]

Aside from the onset of circumcision, the mean heart rate was highest in controls compared to the other groups of patients; this difference was, however, not statistically significant. These findings agree with those of South et al.[8] However, Herschel et al.[13] recorded a statistically significant difference in the heart rates of the three groups studied (P < 0.001). Difference in the technique of circumcision employed (Gomco) and type of sweet solution used for NP (sucrose) might account for the difference in the level of pain experienced and heart rate in their study. In our study, Plastibell technique was used along with dextrose as the agent for NP.

The overall mean age of the participants was 15.47 ± 6.13 days. The age range reported by the present study was similar to the reports by Ogundoyin et al.[14] and Ikhisemojie et al.[15] whose participants most probably shared similar cultural and religious backgrounds with patients in this study as such male circumcision occurred relatively early in life. This is in contrast to the findings of other studies, especially those carried out in Western countries where circumcision is common following the first year of life and sometimes in adulthood.[16] In the studies by South et al.[8] and Herschel et al.,[13] most patients were circumcised within the first 2 days of life. The reason for this variation is probably related to cultural and religious grounds in Nigeria where circumcision is commonly done on the 8th day of life. Patients recruited were solely from the inborn postnatal wards compared to this study where recruitment was from the outpatient clinic.

Similarly, the average birth weight of neonates reviewed in this study was 3.40 ± 0.41 kg, which was comparable to other studies on the same subject including patients studied by South et al.[8] and Herschel et al.[13] In addition, at the time of circumcision, the neonates in this study weighed 3.54 ± 0.56 kg, and this was similar to another study by Ogundoyin et al.[14] in which neonates for circumcision weighed an average of 3.33 ± 0.74 kg.

The indication for circumcision of the patients in our study was uniformly for sociocultural reasons. This is in keeping with many other African countries in which the indication for neonatal circumcision is solely for religious or sociocultural reasons.[17] According to the WHO, these factors contribute to the high prevalence of circumcision, especially in the neonatal period when compared to other countries globally.[18]

The mean duration of the procedure was highest amongst controls (9.53 ± 4.05 min); however, this did not significantly differ from other categories of patients in this study (P = 0.242). The duration of the procedure ranged from 4 min to 24 min overall. This is similar to findings by Herschel et al. (P = 0.78)[13] and South et al. (P = 0.93).[8] The duration of circumcision is, however, often linked to the technique of circumcision chosen and the proficiency of the person carrying out the procedure.

Limitation

This study was, however, limited to the assessment of the behavioural and physiological response to pain in neonates. Evaluation of the endocrine response to pain in addition to the behavioural and physiological response in neonates will constitute an opportunity for further research as this will represent a more robust pain assessment.

 Conclusion



The use of NPs during Plastibell circumcision resulted in significantly better pain scores when compared to the use of NNPs as adjuncts to local anaesthesia in pain assessment scores during male neonatal circumcision.

Neonates in whom NPs were used as adjuncts to local anaesthesia recorded significantly less crying time compared to NNPs and controls, respectively.

There was no statistically significant difference in heart rates of neonates during neonatal circumcision when NPs or NNPs were used as an adjunct to anaesthesia compared to controls.

Acknowledgement

We acknowledge the Lagos State Health Service Commission and General Hospital Randle Lagos for the necessary permission granted to facilitate this work.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

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