Research Article | Vol. 4, Issue 2 | Journal of Pediatric Advance Research | Open Access DOI : http://dx.doi.org/10.46889/JPAR.2025.4204

Effectiveness of Neostigmine versus Dexamethasone as an Adjuvant to Bupivacaine for Caudal Epidural Analgesia Among Pediatrics Surgical Patients at Hospitals in Sodo Town: Cohort Study Design

Naol Gorde Wesene^1*, Mohammed Suleiman Obsa², Ashebir Debalike Gemechu¹

¹Department of anesthesia, Wolaita Sodo University, Wolaita, Ethiopia
²Departments of anesthesia, Arsi University, Arsi, Ethiopia

*Corresponding author: Naol Gorde Wesene, Department of anesthesia, Wolaita Sodo University, Wolaita, Ethiopia;
Email: naolpeace@yahoo.com

Citation: Wesene NG, et al. Effectiveness of Neostigmine versus Dexamethasone as an Adjuvant to Bupivacaine for Caudal Epidural Analgesia Among Pediatrics Surgical Patients at Hospitals in Sodo Town: Cohort Study Design. J Pediatric Adv Res. 2025;4(2):1-10.

Copyright^© 2025 by Wesene NG, et al. All rights reserved. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Variables	DBG(n=45)	NBG(n=45)
	Frequency (%)	Frequency (%)
Age in years
3-5 years	13(14.4%)	10(11.1%)
6-11 years	18(20%)	19(21.1%)
12-14 years	14(15.5%)	16(17.7%)
mean ± SD	8.38 ± 3.525	8.53 ± 3.409
Sex
Male	37(41.1%)	39(43.3%)
Female	8(8.8%)	6(6.6%)
Weight in Kg mean ± SD	30.93 ± 12.447	31.29 ± 12.343

Table 1: Sociodemographic characteristics for patients who underwent sub umbilical and lower extremity surgery at WSUTRH and SCH, from February 29,2020 to May 30,2020 G. C, n=90.

Anesthesia and Surgery-Related Patient Characteristics

In comparing the dexamethasone bupivacaine group to the neostigmine bupivacaine group, both cohorts exhibited surgical diversity with a focus on lower extremity orthopedic procedures. In the dexamethasone bupivacaine group, 20% of patients underwent lower extremity orthopedic surgery, while the neostigmine bupivacaine group had 12.2% of surgical procedures in the same category. Furthermore, both groups included patients undergoing specific surgical interventions such as hypospadia repair in the dexamethasone bupivacaine group (2.2%) and PPV ligation in the neostigmine bupivacaine group (4.4%). While there are variations in the percentages, indicating the specific surgical landscape for each group, the similarities lie in the shared emphasis on lower extremity orthopedic procedures and the inclusion of distinct interventions within each cohort. Additionally, the mean durations of surgery and anesthesia, although slightly different, highlight comparable procedural timelines between the two groups, as detailed in Table 2.

Variables	DBG (n=45) Frequency (%)	NBG (n=45) Frequency (%)
Types of Surgery
Hypospadia (n, %)	2(2.2%)	6(6.6%)
PPV ligation (n, %)	9(10%)	4(4.4%)
Hernia (n, %)	6(6.6%)	9(10%)
Orchiopexy (n, %)	4(4.4%)	5(5.5%)
Lower extremity	18(20%)	11(12.2%)
orthopedic surgery (n, %)	6(6.6%)	10(11.1%)
Others (n, %)
Duration of surgery in minute, (mean ± SD)	55.18 ± 25.307	58.47 ± 21.108
Duration of anesthesia   in minute, (mean ± SD)	64.76 ± 26.410	69.04 ± 21.547

Table 2: Anesthesia and surgery characteristics of patients who underwent sub umbilical and lower extremity surgery at WSUTRH and SCH from February 29, 2020 to May 30, 2020 GC, n=90.

The induction agents and airway management strategies in both the dexamethasone bupivacaine group (DBG) and the neostigmine bupivacaine group (NBG) exhibited notable similarities. A majority of patients in both groups, specifically 60%, received ketamine as their induction agent, emphasizing a consistent approach in anesthesia induction between the two cohorts. Conversely, a minimal percentage of patients, 3.33% in each group, were induced with halothane, highlighting a shared infrequency of this particular agent in both DBG and NBG (Fig. 1).

Regarding airway management, in DBG, 30% of patients received General Anesthesia (GA) with Endotracheal Tube (ETT), while 20% received GA with Laryngeal Mask Airway (LMA). Similarly, in NBG, 33.3% received GA with ETT and 16.16% received GA with LMA (Fig. 2). These comparable distributions underscore the parallel utilization of airway management techniques across both groups, contributing to the overall consistency in anesthesia practices between DBG and NBG.

Perioperative Vital Sign of the Patients

In the dexamethasone bupivacaine group, the majority of Mean Arterial Pressure (MAP) values (24.4%) fell within the range of 66-75 mmHg, while the lowest MAP values were observed in the 45-55 mmHg range. The overall mean MAP was recorded at 62.00 ± 7.693 mmHg. The average heart rate in this group was 116.67 ± 7.167 beats per minute.

In contrast, the neostigmine bupivacaine group exhibited a distribution of MAP values, with 22.2% falling within the 45-55 mmHg range and 10% within the same range. The mean MAP for this group was slightly higher at 63.56 ± 8.049 mmHg. The mean heart rate for the neostigmine bupivacaine group was 116.56 ± 6.930 beats per minute (Table 3).

These findings suggest comparable trends in MAP distribution between the two groups, with dexamethasone bupivacaine demonstrating a slightly lower mean MAP compared to neostigmine bupivacaine. Additionally, heart rate values were consistent across both groups, emphasizing stability in cardiovascular parameters within the studied patient populations, as detailed in Table 3.

Variables	DBG (n=45) Frequency (%)	NBG (n=45) Frequency (%)
Preoperative MAP in mm Hg
45-55 mm Hg	11(12.2%)	9(10%)
56-65mm Hg	12(13.3%)	16(17.7%)
>66-75 mm Hg	22(24.4%)	20(22.2%)
mean ±  SD mm Hg	62.00 ± 7.693	63.27 ± 8.049
Preoperative heart rate	116.67 ± 7.167	116.56 ± 6.930
beats/min(mean ± SD)

Table 3: Perioperative vital sign of patients who underwent sub umbilical and lower extremity surgery at WSUTRH and SCH from February 29, 2020 to May 30, 2020 GC, n=90.

Perioperative Blood Loss and Fluid Replacement of the Patients

Comparing the two groups, both exhibited a similar distribution of intraoperative blood loss, with a substantial proportion experiencing blood loss in the 50-500 ml range. The mean intraoperative blood loss and fluid balance were slightly higher in the neostigmine bupivacaine group but maintained overall comparability with the dexamethasone bupivacaine group (Table 4). These findings suggest comparable intraoperative hemodynamic outcomes between the two anesthetic approaches as detailed in Table 4.

Variables	DBG (n=45) Frequency (%)	NBG (n=45) Frequency (%)
Estimated intraoperative BL in ml
50-500ml	42(46.6%)	40(44.4%)
>500	3(3.3%)	5(5.5%)
mean ± SD	230.67 ± 272.725	255.78 ± 267.577
Intraoperative fluid balance in ml
100-500ml	39(43.3%)	37(41.1%)
>501-1000ml	6(6.6%)	8(8.8%)
mean ± SD ml	490.22 ± 573.119	535.56 ± 530.182

Table 4: Perioperative characteristics of patients who underwent sub umbilical and lower extremity surgery at WSUTRH and SCH from February 29, 2020 to May 30, 2020 GC, n=90.

Postoperative Patient Outcomes

The independent t-test results reveal both similarities and differences in key parameters between the DBG and the NBG for patients undergoing subumbilical and lower extremity surgery. While both groups had similar tramadol consumption, the dexamethasone bupivacaine group demonstrated superior pain relief with a prolonged duration of analgesia and delayed time to the first analgesia request. Additionally, the cost analysis favored the dexamethasone bupivacaine group. These findings collectively suggest that the dexamethasone bupivacaine regimen may provide more effective and cost-efficient pain relief compared to neostigmine bupivacaine in patients undergoing subumbilical and lower extremity surgery, as detailed in Table 5.

Variables	DBG (n=45)	NBG (n=45)	t-value	P-value
Analgesia duration in min, (mean ± SD)	808.00 ± 148.674	716.58 ± 116.503	3.247	0.002
Time till first analgesia request in min, (median ± IQR	733 ± 133	700 ± 233	3.5	0.002
Cost expense in ETB	139.87 ± 34.439	160.29 ± 37.360	-2.696	0.008

Table 5: Postoperative analgesia duration, analgesia consumption, time until first analgesia request, cost expense and pain rating scale for patients who underwent sub umbilical and lower extremity surgery at WSUTRH and SCH from February 29,2020 to May 30,2020 G. C, n=90.

Total Postoperative Rescue Analgesia Consumption

The absence of a statistically significant difference in mean postoperative tramadol consumption between DBG and NBG suggests that both cohorts achieved comparable pain relief using this opioid analgesic. This similarity underscores the effectiveness of tramadol in meeting the analgesic needs of patients in both groups. While there was a statistically significant difference in paracetamol consumption between DBG and NBG, it’s important to highlight that both groups utilized this medication. The observed variance in consumption may reflect individualized pain management strategies rather than a significant divergence in overall pain relief efficacy. The lower diclofenac consumption in DBG compared to NBG, with a statistically significant difference, suggests that patients in DBG required less of this medication (Table 6). However, it’s noteworthy that both groups utilized diclofenac, indicating that patients received analgesics within the moderate range. The observed difference may reflect individual patient responses to pain rather than a substantial divergence in pain relief effectiveness, as detailed in Table 6.

Variables	mean ± SD		t-value	P-value
	DBG (n=45)	NBG (n=45)
Analgesia consumption in mg
Tramadol	65.56 ± 49.477	66.22 ± 52.279	-.062	.951
Paracetamol	98.89 ± 133.454	161.11 ± 162.260	-1.987	.050
Diclofenac	47.22 ± 37.803	70.53 ± 31.194	-3.191	.002

Table 6: Total rescue analgesia consumption for patients who underwent subumbilical and lower extremity surgery at WSUTRH and SCH from February 29, 2020 to May 30, 2020 G. C, n=90.

Postoperative Wong Baker Faces Pain Rating Scale

The mean score of postoperative pain using the Wong Baker faces rating scale was proportionally increased with time. In the neostigmine bupivacaine group, pain intensity was higher than that in the dexamethasone bupivacaine group (Fig. 3).

Incidence of Postoperative PONY and Sedation

The chi-square results showed a significant difference regarding the occurrence of nausea and vomiting between the patients in the Bupivacaine dexamethasone group and the Bupivacaine Neostigmine group (P=0.009). A significant difference was not observed regarding the occurrence of sedation between the patients in the Bupivacaine dexamethasone group and the Bupivacaine Neostigmine group (P=0.271), as detailed in Table 7.

Nausea and Vomiting	Yes	No	X2	P-value
Bupivacaine Dexamethasone Group	2(2.2%)	43(47.7%)	6.852	.009
Bupivacaine Neostigmine Group Sedation	12(13.3%)	33(36.6%)
Bupivacaine Dexamethasone Group	19(21.1%)	26(28.8%)	1.212	.271
Bupivacaine Neostigmine Group	13(14.4%)	32(35.5%)

Table 7: Incidence of PONY and sedation for patients who underwent subumbilical and lower extremity surgery at WSUTRH and SCH from February 29, 2020 to May 30, 2020, n=90.

Discussion

In our study, we compared the effectiveness of dexamethasone and neostigmine as adjuvants to caudal epidural analgesia for pediatric patients. Sonography was not included in our study, which allows easy identification of sacral anatomy to ease the degree and proper site of local anesthetic injection [47]. The current study shows that the mean duration of analgesia was 808.00 ± 148.674 in the dexamethasone bupivacaine group, whereas in the neostigmine bupivacaine group, it was 716.58 ± 116.503 with a p value of .002, which is shorter than that in the study conducted in IGMC Shimla, India, with a mean duration of 1410.84  ±  37.7543 in the dexamethasone ropivacaine group and in the neostigmine ropivacaine group, it was 943.12  ±  32.5376. The relatively prolonged mean duration of analgesia in their study was due to sonographic guidelines, which increased the accuracy of the injection site [43]. The results of systematic review and meta-analysis show that the duration of analgesia was significantly prolonged in dexamethasone as an adjuvant compared to placebo after caudal block, which is also the same result as our study [42].

Similar to our results, the study conducted in Madani Hospital Tabriz, Iran, declares that the addition of 8 mg dexamethasone to bupivacaine for epidural analgesia significantly prolongs the duration of analgesia [48]. Another comparative study also explains that the addition of dexamethasone to local anesthetics significantly prolongs the duration of analgesia for caudal epidural analgesia after unilateral inguinal hernioraphy [49].

The incidence of nausea and vomiting was high in the neostigmine bupivacaine group compared to the dexamethasone bupivacaine group. This result is similar to the study conducted in Egypt, Tanta University [50]. In contrast, the study conducted in Severance Hospital at the Yonsei University Health System shows that the incidence of postoperative nausea and vomiting was not found in the dexamethasone bupivacaine group, but two cases were found in our study, which was due to opioid-based postoperative pain management [40].

In our study, two cases of nausea and vomiting were reported in the dexamethasone bupivacaine group, which is closest to the comparative study conducted in government General Hospital, Kakinada, India [6]. Another study also shows that neostigmine with bupivacaine is associated with postoperative nausea and vomiting when compared with bupivacaine alone [51].

The mean duration of analgesia in our study was prolonged when compared to the comparative study conducted in Nepal, on dexamethasone versus neostigmine as adjuvant to lidocaine with adrenaline for brachial plexus block, in which the mean duration of analgesia was higher in the dexamethasone group (454.2 ± 110.7 minutes) compared to the neostigmine group (225.7 ± 53.3 minutes) [52]. The short mean duration of analgesia in their study was due to the use of lidocaine and the brachial plexus area by itself is highly vascularized and uptake of local anesthesia is high.

Postoperative rescue analgesia consumption was low in the dexamethasone bupivacaine group in our study. Similar to our finding, the study conducted in Sawai Man Singh Medical College Hospital, India, on analgesia requirements explains that there was less need for analgesic requirements during the 24-hour post-operative period in patients who received dexamethasone as adjuvants when compared to local anesthetics alone [25]. On the other hand, a study conducted at Tanta University, Egypt, showed that postoperative analgesia consumption was lower in the neostigmine bupivacaine group than in the bupivacaine alone group [39].

The duration of the first analgesia request in our study was prolonged in the dexamethasone bupivacaine group. Another study, Sri Ramachandra University, India, showed that the duration of first analgesia request was higher in the dexamethasone bupivacaine group for patients who underwent infraumbilical surgery, which is similar to our study results [41]. The results of a comparative study also found that neostigmine bupivacaine has lower rescue postoperative analgesia consumption than bupivacaine alone [53].

The incidence of postoperative sedation was not significantly different between the dexamethasone bupivacaine group and the neostigmine bupivacaine group in our study. In line with our study, a comparative study conducted at Zagazig University, Egypt, revealed that postoperative sedation was not significant in dexamethasone after caudal epidural analgesia [54]. Strength of the study: Both the exposed and unexposed groups were selected from the same source population. No patients were lost to follow-up, which resulted in missing data.

Limitation

One of the limitations of this study was the failure to assess the adverse effects of the study drugs beyond 24 hours.

Conclusion

The results of our study show that there was a significant difference between the dexamethasone bupivacaine group and the neostigmine bupivacaine group in the duration of analgesia. Time until first analgesia request was higher in the dexamethasone bupivacaine group than in the neostigmine bupivacaine group. There was no significant difference in postoperative rescue tramadol consumption, but diclofenac and paracetamol consumption was significantly different. The incidence of postoperative nausea and vomiting was marked in the neostigmine bupivacaine group compared to the dexamethasone bupivacaine group. However, postoperative sedation was insignificant in the dexamethasone bupivacaine group and neostigmine bupivacaine group. Cost expense was higher in the neostigmine bupivacaine group than in the dexamethasone bupivacaine group.

Conflict of Interests

The authors have no conflict of interest to declare.

Availability of Data and Materials

Data will be available with reasonable request from the corresponding author.

Acknowledgements

We extend our gratitude to Wolaita Sodo Teaching Referral Hospital and Sodo Christian Hospital authorities and staff, supervisors, data collectors and respondents who participated in this study.

Author Contributions

NG contributed to the conception, design of the study, data acquisition, data entry, analysis and interpretation of the data and drafted and revised the manuscript. MS, RO and AD contributed to the conception and assisted in the initial design of the study, analyzed and interpreted the data and critically revised the manuscript. Both authors read and approved the final manuscript.

Ethics Approval and Consent to Participate

Not applicable for this paper.

Funding

Wolaita Sodo University, but the funder has a role in publishing this research.

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