European Journal of Cardiovascular Medicine

Caudal Epidural was initially introduced in 1901 by Cathelin and Sicard. In 1993, Meredith Campbell, a urologist, was the first to report the application of caudal anaesthesia for cystoscopies in pediatric patients. The postoperative pain experienced by children and adolescents is often overlooked, even though it can sometimes result in significant morbidity and mortality.^1,2 Utilizing pain scales, such as FLACC, is essential for the effective management of pediatric patients. There are multiple pathways involved in postoperative pain. Implementing a multimodal analgesia strategy is crucial, encompassing both opioid and non-opioid analgesics to enhance pain relief while reducing the risks associated with polypharmacy and side effects.³ When peripheral tissue is damaged, it can trigger sensitization in both the peripheral and central nervous systems.^4,5

This condition is marked by an increased sensitivity to pain, even when there is no actual injury present. In pediatric patients undergoing lower abdominal, inguinal, or penoscrotal surgeries, caudal anesthesia is a frequently used localized method for managing pain during and after the surgical procedure.⁶ This approach can also be utilized during the operation itself. Besides being relatively easy to administer, it is safe, reliable, and offers sufficient pain relief for surgeries below the umbilical region. Conversely, the effects of caudal bupivacaine may last anywhere from four to twelve hours. The duration of post-operative pain relief can be prolonged with the use of various additives.⁷

The use of caudal morphine is linked to a greater occurrence of significant side effects like respiratory distress, nausea, vomiting, and urinary retention.⁷ Nonetheless, the pain relief it provides is exceptional. Besides bupivacaine, various other combinations, including ketamine, clonidine, tramadol, and midazolam, have been used. These medications carry risks that may result in hypotension, behavioral issues, vomiting, and sedation.⁸ Among these drugs, midazolam stands out as the primary option in this category.

Paracetamol is recognized as an effective pain reliever. It is safe and conveniently administered to children, especially in suppository form, and it has a wide range of therapeutic applications. Using rectal paracetamol avoids the side effects typically linked to nonsteroidal anti-inflammatory drugs (NSAIDs). These side effects can include coagulopathy, nephritis, gastropathy, and bronchial asthma.^9-11 Paracetamol provides excellent postoperative pain relief due to its centrally acting influence on the nociceptive process, which encompasses central sensitization.¹²

The objective of this research was to examine the effectiveness of pain relief provided by rectal paracetamol combined with caudal bupivacaine in children who underwent sub-umbilical surgeries.

AIM: To assess the efficacy and extent of postoperative analgesia of paracetamol rectal suppository with caudal bupivacaine, in paediatric subjects undergoing subumbilical surgeries in comparison with caudal bupivacaine alone.

OBJECTIVES:

• To compare Postoperative pain severity using FLACC scale.
• To compare extent of postoperative analgesia among groups.
• Compare vital parameters in both groups postoperatively.

Study Design: A prospective randomized study.   

Study area: The study was conducted in Department of Anaesthesiology, SVRRGH, Tirupati.

Study Period: 1 year.

Study population:  This study comprised of pediatric patients undergoing sub umbilical surgeries, aged from 3 to 8 years weighing less than 20 Kg of either gender, ASA-1.

Sample size: Study consisted a total of 60 subjects.

Sampling Technique:  Simple Random technique.

Inclusion Criteria:

• Patients undergoing sub-umbilical surgeries.
• Age 3- 8 years.
• Weight < 20 KGs.
• Children in ASA-1 category.
• Parent or Guardian willing to give consent.

Exclusion criteria:

• Children with h/o allergy to local anaesthetics.
• Undiagnosed diarrhoea.
• Local sepsis (Caudal)

Ethical consideration: Institutional Ethical committee permission was taken before the commencement of the study.

Study tools and Data collection procedure:

Randomization was used to divide sixty children, all of whom belonged to the ASA I category and were scheduled to have sub-umbilical surgeries, into two groups. Caudal bupivacaine, also known as Group C, and Group S (Caudal bupivacaine with paracetamol suppository). Patients will be randomly allotted to two groups by computer generated random table and sealed opaque envelope technique. Subject is given a sealed envelope which contains the group allocation and opened only after valid consent obtained, then patient is allotted to that group. Thus randomization sequence will be generated before initiating the study. Sixty patients will be recruited during the study period.

Premedication: Inj. Glycopyrrolate 0.04mg/kg I.V⁸. Inj. Ondansetron 0.1mg/kg I.V.

Monitoring; Parameters Monitored are Pre induction HR, SpO2, RR, ECG, BP and Surface Temperature. Post induction HR, SpO2, RR, ECG, BP and Surface Temperature. Intraoperatively continous monitoring of HR, RR, ECG, SpO2, BP and Surface Temperature was done and recorded every 5 mins till the surgery is completed. Postoperatively assessment of pain was done using FLACC pain scale. Postoperative nausea and vomiting.

Obtain consent for the procedure from the parents. After induction of short general anaesthesia and airway control, the patient is positioned laterally (or ventrally), with their hips flexed to 90°. Skin disinfection should be performed carefully, because of the proximity to the anus. Aseptic technique should be maintained.

The procedure needs to be carried out using an aseptic technique that is very precise. Thorough preparation of the skin is necessary, as is the use of sterile gloves. Any infection that affects the caudal area is a very dangerous condition. It is possible to detect the sacral hiatus by first palpating the coccyx and then sliding the palpating finger in a cephalad direction (towards the head) until a depression in the skin is felt. This is how the sacral hiatus can be found. The distance that extends from the end of the coccyx to the sacral hiatus in an adult is roughly equivalent to the length that extends from the end of the index finger to the proximal interphalangeal joint in that digit.

Confirmation of bony landmarks is essential to achieve success in this location because there is the potential for a high degree of anatomical variance in this area. The sensation of entering the sacral hiatus can be reproduced by inserting the needle via any one of a variety of distinct structures. It is essential to determine the midline of the sacrum since there is a large amount of diversity in the prominence of the cornua, which can lead to complications if proper precautions are not taken. After the sacral hiatus has been located, the region above it is thoroughly sterilised with an antiseptic solution. Next, a 22-gauge short bevelled cannula or needle is positioned at about 45 degrees to the skin and inserted until a "click" is felt as the sacro-coccygeal ligament is pierced. This procedure is repeated until the sacral hiatus has been completely accessed. After this, the needle is guided with extreme care in a cephalic direction at an angle that is becoming closer to the longitudinal axis of the spinal canal. The highest dose of 0.25% Bupivicaine that is suggested is 2 milligrams per kilogram.

Under aseptic conditions, each of the sixty children got a caudal epidural injection of 0.25% bupivacaine at a rate of 1 millilitre per kilogram while lying on their left side. Following a caudal epidural, each of the thirty children who fell into the Group S category were given lignocaine gelly and a dose of rectal paracetamol ranging from 15-20 mg/kg. Thirty children in Group C were solely given caudal epidural anaesthesia as their only kind of anaesthesia.

Postoperatively, immediately after surgery, patients were transported to the recovery room. The mother was given permission to be with the child in order to provide tender loving care, and all postoperative parameters were monitored in the recovery room at regular intervals of 15 minutes for the first two hours and 30 minutes for the following three hours. After an initial two hours after operation, children were started on oral feedings.

Statistical analysis:

A total of 60 children who had undergone sub-umbilical surgery were included in the study. They were divided into two groups: Group S (caudal bupivacaine with rectal paracetamol) and Group C (caudal bupivacaine alone). Postoperative outcomes were assessed using the FLACC pain scale, rescue analgesic time, modified Aldrete recovery score, postoperative nausea and vomiting (PONV), fever, and time to first urine voiding.

Group S showed significantly longer and better-quality analgesia with lower pain scores compared to Group C, despite receiving the same amount of analgesia. Group C had a higher incidence of PONV and fever. Most children voided urine within 6–7 hours post-surgery, and no catheterization was required. Statistical analysis was done using Levene's test and t-test for continuous variables and Chi-square test for gender distribution and PONV incidence.

TABLE 1: COMPARISON OF MEAN AGE DISTRIBUTION BETWEEN GROUPS

The age groups in both the Group C & S were found to be statistically comparable by paired t test. The Mean ± SD of Age in Study and Control groups are 5.1±1.8 years and 5.3 ± 2.4 years respectively which is not statistically significant (t=0.345, p>0.05).  All the cases of the study population were males.

TABLE 2: WEIGHT DISTRIBUTION WISE TIME FOR RESCUE ANALGESIA

By using the paired t test, it was discovered that the weight distribution in Group C and Group S were statistically equivalent to one another.. In both the caudal bupivacaine with rectal paracetamol group and the caudal bupivacaine group, the distribution of all cases in each weight group is comparable, and in all weight groups, there is a significant increase in rescue analgesic time in the caudal bupivacaine with rectal paracetamol group. The time needed to administer Rescue analgesic is increased by 4 hours 41 minutes in the 10-12 kg Group C patient, by 4 hours 51 minutes in the 13-15 kg Group C patient, by 4 hours 44 minutes in the 16-18 kg Group C patient, and by 4 hours 48 minutes in the 19-20 kg Group C patient.

The time needed to administer Rescue analgesic is increased by 5 hours 54 minutes in the 10-12 kg Group C, by 5 hours 23 minutes in the 13-15 kg Group C, by 5 hours 31 minutes in the 16-18 kg Group S, and by 6 hours 03 minutes in the 19-20 kg Group S.

TABLE 3: COMPARISON OF TIME FOR RESCUE ANALGESIA BETWEEN GROUPS

When comparing the study group and the control group in terms of the mean R.A. Time, there is a highly significant difference between the two groups (t = 3.435, p 0.0001).

TABLE 4: COMPARISON OF HEART RATE DISTRIBUTION DURING DIFFERENT TIME INTERVALS BETWEEN GROUPS

Because Group S has a significantly lower heart rate than Group C at all post operative time intervals, this indicates that Group S received a higher level of post operative analgesia.

Table 5: COMPARISON OF RESPIRATORY RATE DISTRIBUTION DURING DIFFERENT TIME INTERVALS BETWEEN GROUPS

At all post-operative time intervals, the respiratory rate is significantly lower in Group S compared to Group C, which indicates that the quality of post-operative analgesia is superior in Group S.

TABLE 6: COMPARISON OF ALDRETE DISTRIBUTION DURING DIFFERENT TIME INTERVALS BETWEEN GROUPS

The Aldrete recovery score in Group C is statistically significantly higher at all time intervals than it is in Group S. This difference is statistically significant. 

TABLE 7: COMPARISON OF FLACC DISTRIBUTION DURING DIFFERENT TIME INTERVALS BETWEEN GROUPS

There were five factors that were taken into consideration for the FLACC, and each of those criteria received scores of 0, 1, and 2 for an absence, moderate, and severe response to pain, respectively.

The pain score is considerably lower in the study group S (caudal bupivacaine with rectal paracetamol) than it is in the control group C [caudal bupivacaine alone] at all post operative intervals.

TABLE 8: COMPARISON OF INCIDENCE OF POST OPERATIVE COMPLICATIONS BETWEEN GROUPS

When compared with Group S, the incidence of post-operative nausea and vomiting, as well as an increase in temperature, is significantly higher in Group C.

The first postoperative urine voiding time in the study group is 5.41 hours, while the time in the control group is 4.38 hours. This difference is statistically significant (t = 3.434, p 0.05).

The aim of this study was to determine the feasibility of conducting paediatric sub umbilical surgery using a combination of a rectal paracetamol suppository and caudal bupivacaine. To evaluate the effectiveness of this combination in paediatric sub umbilical surgeries, the procedure was performed. A total of sixty patients were randomly selected and assigned to either Group S or Group C, with each group containing thirty participants. Those in Group C received only caudal bupivacaine, while participants in Group S were administered both caudal bupivacaine at 0.25% (1 ml/kg) and a rectal paracetamol suppository at 20 mg/kg. Group C individuals were given only caudal bupivacaine after obtaining proper consent from their parents. The FLACC scale was employed to measure the pain levels experienced by both groups, allowing for appropriate comparisons between them.

Alongside this, data such as the duration for the analgesic to take effect, the patient's heart rate, respiratory rate, sedation score, aldrete recovery score, occurrences of postoperative nausea and vomiting, the initial instance of the patient voiding urine, and the patient's elevated temperature were all documented.   Group S exhibited a significantly lower FLACC pain score compared to Control Group C, indicating that the combination of caudal bupivacaine with rectal paracetamol provided superior postoperative pain management than Control Group C, which relied solely on caudal bupivacaine.

The administration of paracetamol rectally in patients from Group S takes a longer duration before they notice an increase in pain intensity. For Group C, with a weight range of 10-12 kg, the extension for rescue analgesic time is 4 hours and 41 minutes; Group D, weighing 13-15 kg, benefits from a 4 hour and 51-minute extension; Groups in the 16-18 kg range experience a 4 hour and 44-minute extension; and Group D, with a weight of 19-20 kg, has a 4 hour and 48-minute extension. In the case of patients weighing 10-12 kg in Group C, they receive an additional 5 hours and 54 minutes of rescue analgesic time, while those in the 13-15 kg range get an extra 5 hours and 23 minutes. Patients weighing 16-18 kg benefit from an additional 5 hours and 31 minutes, and those in the 19-20 kg category receive an increased 6 hours and 3 minutes.

Research indicates that there is a notable difference in heart rates between Group S and Group C. The improved quality of postoperative pain relief in Group S is evident by a significantly lower heart rate in comparison to Group C throughout all postoperative intervals. Differences in respiratory rates between Group S and Group C were also observed. A statistically significant variation in respiratory rates exists between these two groups at all postoperative time points, wherein Group S demonstrates a lower rate signifying superior postoperative analgesia.  Furthermore, occurrences of postoperative nausea and vomiting, as well as increases in temperature, are more frequently observed in Group C than in the other groups.

A 2008 study by Gupta et al.¹³ compared caudal bupivacaine (0.25%, 0.5 ml/kg), rectal diclofenac (1 mg/kg), and their combination in children after sub-umbilical surgery. Results showed: 

- Group I (bupivacaine alone): 8.2 ± 1.3 hrs analgesia 

- Group II (diclofenac alone): 8.3 ± 1.3 hrs analgesia 

- Group III (combination): 13 ± 2.3 hrs analgesia 

In contrast, our study used rectal paracetamol (instead of diclofenac) with caudal bupivacaine, achieving shorter analgesia (~5 hrs 50 mins) compared to the earlier study. This suggests diclofenac may provide longer pain relief than paracetamol in this setup.

In a study involving pediatric patients undergoing surgeries below the umbilical region, Raghavan et al.¹⁴ (2012) assessed the effectiveness of postoperative pain relief provided by rectal paracetamol suppositories compared to caudal bupivacaine. The research included sixty children who underwent a range of surgical procedures. The aim of the investigation was to evaluate the two analgesic methods and determine if one was superior in alleviating postoperative discomfort.

The findings indicated that the group receiving rectal paracetamol S had a significantly extended duration of postoperative pain relief compared to the group receiving only caudal bupivacaine C, based on Mean Rescue Analgesic Time measurements. This conclusion was supported by the fact that the rectal paracetamol group S enjoyed a markedly prolonged period of analgesia after surgery. The longer postoperative analgesic duration observed in rectal paracetamol group S reinforces the primary conclusion of the study. This research closely aligns with our work and exhibits similar outcomes. With a P value below 0.0001 and a t value of 13.9 or higher, both Group S (353 minutes less than 6.0) and Group C (253 minutes less than 3.9) reported experiencing analgesia. 

Research by Bertolini et al.¹⁵ suggests that paracetamol’s analgesic effects may involve mechanisms beyond COX inhibition. In the CNS, paracetamol is converted to AM404 (N-arachidonylphenolamine), which interacts with both capsaicin (TRPV1) and cannabinoid CB1 receptor systems. These pathways independently contribute to central analgesia. AM404 also plays a role in paracetamol’s antipyretic effect by inhibiting brain prostaglandin synthesis.

In a study that was carried out by Rahman M et al.¹⁶, a comparison was made between the effects of bupivacaine combined with neostigmine, bupivacaine combined with fentanyl for postoperative analgesia in children. The Sher-E-Bangla Medical College Hospital in Barisal was going to perform surgical procedures on each and every one of the children who took part in the trial. All of them, ranging in age from 2 to 8years, took part in the research project that was being conducted. There were a total of ninety children that took part in the research project as participants. Based on the degree to which they were affected by their disease, the American Society of Anesthesiologists categorised these young patients as either grade I or grade II. In children undergoing sub-umbilical procedures, the addition of fentanyl or neostigmine to bupivacaine increased the duration of surgical anaesthesia and postoperative analgesia with a single caudal injection, with a low incidence of adverse effects. This was the case despite the fact that a much higher number of youngsters reported having negative effects as a result of the exposure. This shows the fact that a significantly higher percentage of young people reported suffering adverse effects as a direct result of the exposure. This was the situation despite the fact that both drugs increased the amount of time the patient was under anaesthesia as well as the amount of time that the patient remained pain-free after the surgical procedure. This method, which has the advantages of being both cost-effective and safe, can be substituted for the insertion of an extradural catheter during procedures that helps to increase the length of postoperative analgesia.

In a study by Golladay, Suehutter, et al.¹⁷, 54% of children receiving rectal paracetamol post-peritonioscopy required no further analgesia for 24 hours, suggesting its efficacy as a standalone postoperative analgesic. Our study, however, administered 20mg/kg rectal paracetamol with caudal bupivacaine, unlike their study which compared rectal paracetamol and caudal bupivacaine separately. Despite methodological differences, both studies indicate that rectal paracetamol provides good postoperative analgesia.

Shreshta et al.¹⁸ (2010) found that caudal bupivacaine + tramadol (Group B) provided longer analgesia (8.8 hrs) compared to bupivacaine alone (Group A: 7 hrs), but with a higher rate of nausea/vomiting (25% vs. 20%). No major complications (e.g., urinary retention) were reported. In our study, we used rectal paracetamol + bupivacaine instead of tramadol, resulting in fewer side effects (lower PONV and fever rates) but shorter analgesia (~5 hrs 50 mins) compared to tramadol. This highlights that tramadol provides longer pain relief but with more side effects, whereas paracetamol offers safer but shorter analgesia.

Rajan et al.¹⁹ (2017) compared caudal bupivacaine alone (Group B) versus bupivacaine + clonidine (Group BC) in children undergoing lower abdominal surgery. Key findings: Group BC (bupivacaine + clonidine) provided longer and stronger analgesia with reduced need for rescue painkillers compared to bupivacaine alone. However, the combination (BC) had more side effects than bupivacaine alone, despite both being generally mild. This suggests that while adding clonidine enhances pain relief, it may also increase side effects. Our study differs by using rectal paracetamol instead of clonidine, prioritizing safety over prolonged analgesia.

Dmytriiev DV and colleagues (2020)²⁰ conducted an investigation into the efficiency of a caudal block Group C with 1 ml/kg of 0.2% bupivacaine compared with ultrasound guided quadratus lumborum block Group  Q with 0.5 ml/kg of 0.25% bupivacaine in elective appendicitis cases and determined whether or not the patient required rescue analgesia while they were undergoing surgery as well as after the procedure. As a last-ditch effort to alleviate the patient's pain, an emergency dose of acetaminophen at a rate of 20 milligram per kilogram was administered to them. Postoperative analgesia was evaluated using CHIPPS score.in our study we use FLACC scale to access the postoperative analgesia.

According to the findings of Gandhi M. and colleagues (2021)²¹, the combination of 0.1 mg/kg of dexamethasone with 0.25% bupivacaine for caudal block and administration of the mixture as a 1 ml/kg mixture in children undergoing infra-umbilical surgeries resulted in a prolonged duration of analgesia (time to first rescue analgesia) with hemodynamic stability, as well as a significant reduction in total opioid requirement. In our study we used the paracetamol suppository along with caudal bupivacaine instead of dexamethasone used in their study.

In the study that was carried out by Jan Muhammad Shaik and Sikander ali Mughal et al.²², in which 143 patients were given solely caudal bupivacaine, the incidence of post-operative nausea and vomiting was discovered to be 33% in Group C caudal bupivacaine alone . The study was conducted on patients who had undergone caudal bupivacaine injections. Only patients who had received bupivacaine injections in the caudal region were used for the research in this study. After analysing these findings, in our study found that Group C had a significantly lower incidence of post-operative nausea and vomiting than the other groups did. The people who took part in the study who were assigned to Group C had a one in sixteen and a half percent chance of experiencing an increase in temperature, whereas none of the people who were assigned to Group S were experienced rise in temperature.

Due to the fact that Group C had a P value that was higher than 0.05, it can be deduced that the amount of time that passes between the first and second times a person empties their bladder is significantly longer in Group S (5 hours 41 minutes) than it is in Group C. This is because a P value that is less than 0.05 indicates that the difference between the two groups is significant. (4 hours 38 minutes). According to the findings of a study that was carried out by Jan Muhammad Shaik and Sikander ali Mughal et al26, the amount of time that it took for a child to evacuate urine after the administration of caudal bupivacaine ranged anywhere from six to eight hours on average. During the course of my investigation, neither group shown any evidence of urine retention, nor did any of them require a procedure that required catheterization. Additionally, none of them required a technique that required me to catheterize them. In addition, none of them needed a procedure that required me to catheterize them, which was a huge relief. A catheter did not need to be placed into the urinary tract of any of them, which is another positive sign.

We conclude, based on the results of the previously mentioned research, that incorporating a paracetamol suppository with caudal bupivacaine enhances the quality of post-operative pain relief and prolongs its duration more effectively than caudal bupivacaine on its own in pediatric patients undergoing surgeries below the umbilical region, thus meeting the criteria outlined in the study's objectives.

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