Background: Our study aims to the compare the duration of post-operative analgesia, times of post-operative opioid consumption, post-operative sedation score, and haemodynamic changes between the groups on using 8mg Dexamethasone and 75 μgm clonidine as an adjuvant to 0.25% Ropivacaine in ultrasound-guided bilateral TAP block in patients undergoing total abdominal hysterectomy. Study design: Prospective, randomized, double blinded study with 56 patients were included and allocated using a -generated randomization code into: Group A (n=28 patients): Received USG guided bilateral TAP block with Injection Ropivacaine (0.5%) 20ml + Dexamethasone (8 mg) 2ml + Normal Saline 18 ml and Group B (n=28 patients) Received USG guided bilateral TAP block with Injection Ropivacaine (0.5%) 20ml + clonidine (75mcgs) 0.5 ml + Normal Saline 19.5 ml. Results: The duration of pain relief was highest (14.3 ± 4.7 hours) in group B patients compared to group A (11.1 ± 5.1 hours). The duration of analgesia provided by 75 mcg clonidine was statistically significant (p<0.001). Post-operative opioid consumption was higher in group A compared to group B which is statistically not significant. (P>0.05). There was also no significant difference in between the study groups for sedation scoring and haemodynamic changes. Conclusion: The addition of dexamethasone 8mg or clonidine 75 mcgs to 0.25% ropivacaine significantly prolongs the duration of analgesia and reduces postoperative opioids requirement, thereby facilitating early recovery and ambulation. On comparing, clonidine appears to be superior adjunct, in terms of pain relief. |
The post-menopausal age group is where hysterectomy surgery is most frequently performed on women worldwide. Total abdominal hysterectomy (TAH), Laparoscopic assisted vaginal hysterectomy (LAVH), and total laparoscopic hysterectomy (TLH) are the various approaches to do hysterectomy. The selection of the surgical process would always determine the mode of anaesthesia used, either regional anaesthesia or general anaesthesia.
The International Association for the Study of Pain (IASP) specify pain as “an unpleasant sensory and emotional experience associated with actual or potential tissue damage or described in terms of such damage”1. This procedure prompts significant postsurgical pain and discomfort.2
Unwanted adverse events range in severity from surgical discomfort that is not well managed, from the discomfort of patients, immobility, to the thromboembolic phenomena and pulmonary complications.3 A regional block called the Transversus Abdominis Plane (TAP) is given to the lateral and anterior abdominal walls via an anaesthetic block.4
Following this, Hebbard proposed an ultrasound-guided approach to the Transverse abdominis plane block.5 The neuro-fascial plane must be accurately identified to be successful amidst the transversus abdominis and internal oblique muscles. Ultrasound-based studies have demonstrated that injections into the abdomen wall are not very accurate.5 Regrettably (TAP) block duration is constrained by the effectiveness of certain local anaesthetics (LA). Adjuvants are also used to extend the (TAP) block's effects.
Numerous studies have demonstrated the efficacy of transverse abdominal plane (TAP) block, a technique that uses ropivacaine or bupivacaine to relieve postoperative pain. However, these duration blocks that use only local anaesthetics have an effect for a few hours.Dexmeditomidine and clonidine are administered as adjuvants to boost the effectiveness of peripheral nerve block. It has been discovered to be generally safe to use with local anaesthetic throughout the length of analgesia.7
TAP block's analgesic effectiveness when administered with only local anaesthetic is acceptable; however, adding opioids like fentanyl, magnesium, and adjuvants like clonidine, ketamine, dexamethasone, dexmedetomidine, and tramadol were discovered to lengthen the sensory block providing prolonged post-operative analgesia following surgery.8
A synthetic glucocorticoid called dexamethasone works to reduce inflammation by prevention of release of cytokines and interleukins.9 A number of studies have showed that adding dexamethasone to local anaesthetics before surgery has potential reduction in postoperative discomfort and enhancements to analgesia quality.10
Consequently, the motive of this study was to compare the length of post-operative analgesia using Ropivacaine 0.25% with Dexamethasone 8mg vs Clonidine 75mcg as an adjuvant for ultrasound-guided Transversus Abdominis Plane block for patients receiving spinal anaesthesia during an abdominal hysterectomy.
After attaining approval from Institutional Human Ethics Committee, 56 patients registered for total abdominal hysterectomy under spinal anaesthesia in the Department of Anaesthesiology, Chettinad Hospital and Research Institute, meeting the following selection criteria were included in the study.
The enrolled 56 participants were haphazardly divided into 2 groups (28 in each group) using a computer generated randomization code. Patients in each group received an Ultrasonogram-guided TAP block:
Group - A: (n=28) 0.5% Ropivacaine 20ml + Dexamethasone 2ml (8 mg) + normal saline 18ml Total volume = 40ml
Group - B: (n=28) 0.5% Ropivacaine 20ml + Clonidine 0.5ml (75 mcg) + normal saline 19.5ml Total volume = 40ml.
INCLUSION CRITERIA:
All American Society of Anaesthesiologists (ASA) physical status classes I and II and patients with age between 21–65 years of age were included.
EXCLUSION CRITERIA :
Patients with BMI > 35 kg/m2 , Height < 150cms, Known allergy to local anaesthetics, Coagulopathies, Local infection at site of injection and with History of heart block, dysrhythmias were excluded from the study.
All patients underwent preoperative assessment in the pre-anaesthetic assessment clinic and were assessed again the day before surgery.
When the patients arrived at the pre-anaesthetic reception area, the consent forms were examined again, an IV access was established, and 500 mL of Ringer Lactate was administered. Hemodynamic monitoring devices (3-lead ECG monitoring, heart rate, blood pressure, and oxygen saturation) were attached as soon as the patient was moved to the operating room.
Patient parts were prepped with 2% chlorhexidine and draped while they were in a sitting position and subject to strict aseptic procedures. After identifying the L3-L4 or L4-L5 space, 2% lignocaine was infiltrated. Spinal anaesthesia was then given using a 26G or 27G Quincke needle. The subarachnoid space was located by free flow of cerebrospinal fluid. 3.5ml of 0.5% hyperbaric Bupivacaine with 25mcgs fentanyl (0.5ml), for a total volume of 4 ml were given after barbotage of CSF confirmation. The patients received a bilateral TAP block with USG guidance following the surgery. A 3-lead ECG monitoring, systolic and diastolic blood pressure, saturation of oxygen, mean arterial pressure and heart rate were all recorded intraoperatively every 2-3 minutes of subarachnoid block for the first 20 minutes, every 10 minutes for next 60 minutes, and then every 15 minutes until the surgery was complete. The patient was excluded from the trial in the event that the anaesthesia was changed to general anaesthesia.
Immediately after giving USG guided TAP block, the subject were shifted to post-operative recovery, where they were monitored for the following assessments for every 30 minutes for 1 hour, then for every 1-hour till 4-hours, then for every 4-hours till 24-hours post operatively. Post-operatively, patients will be assessed for, 1.Pain using Visual Analogue Scale (VAS) hourly, till patient reports VAS >3. 2.Time frame for post-operative analgesia and the time when first rescue analgesic is needed. 3.Post-operative shivering was monitored every hourly for 6 hours. 4.Post-operative sedation score using Ramsay sedation score every hourly for 6 hours. In PACU, all patients received a baseline Injection.Paracetamol 1 gram every 8th hourly. If the patient complaints of pain, patient was given Injection Tramadol 50mg IV slow as a rescue analgesic if the VAS score >3. Any complications were noted and managed accordingly.
The study included 56 female participants who were haphazardly divided into two groups 28 cases in each group, who were planned for elective TAH with or without bilateral salphingo-oophorectomy.
Table:1 Descriptive analysis of ASA and Type of surgery
Variable |
Group A |
Group B |
P Valve |
ASA I |
13 |
15 |
0.593 |
ASA II |
15 |
13 |
0.593 |
Total abdominal hysterectomy |
6 |
9 |
0.365 |
Total abdominal hysterectomy + BSO |
22 |
19 |
0.365 |
Variable |
Group A Mean ± SD |
Group B Mean ± SD |
P valve |
Age |
47.5 ± 7 |
48.3 ± 7.9 |
0.71 |
Weight |
72.3 ± 10.4 |
68.5 ± 8.3 |
0.137 |
Height |
159.9 ± 5.2 |
159.1 ± 4.8 |
0.544 |
BMI |
28 ± 3.5 |
27.1 ± 3.4 |
0.35 |
Table 2: Descriptive analysis of BMI (kg/m2), height (cm), weight (kg), and age (years) expressed as mean ± standard deviation for each group
Time to sensory level:
Table 3: Time to sensory level T6 (mins) between the study groups (n = 56)
Time to sensory level T6 (mins) |
Group A (n= 26) |
% |
Group B (n=26) |
% |
P valve |
2 mins. |
1 |
3.7 % |
2 |
7.4% |
0.397 |
3 mins |
7 |
25.9% |
3 |
11.1% |
|
4 mins |
10 |
37% |
11 |
40.7% |
|
5 mins |
7 |
25.9% |
7 |
25.9% |
|
6 mins |
2 |
7.4% |
4 |
14.8% |
|
Figure 1: Means of post-operative heart rate
Post-operative heart rates were documented and related between both the groups immediately after giving TAP block, at a different time intervals - 0 mins, 30 mins, 1-hour, 1.5-hour, 2-hours, 3-hours, 4-hours, 8-hours, 12-hours, 16-hours, 20-hours and 24-hours post operatively. Over a period, there is significant difference between the post-operative heart rate, but there is no difference in the HR between the groups A and B.
Figure 2: Means of post-operative SBP
Post-operative systolic blood pressure (SBP) was recorded and compared between both the groups from the time of TAP being given, at different time intervals as mentioned, for 24 hours post operatively. Over a period, there is significant difference between the post-operative systolic blood pressure but there is no difference in the SBP between the groups A and B.
Figure 3: Means of post-operative DBP
Post-operative diastolic blood pressure (DBP) was recorded and compared between both the groups immediately after giving TAP block, at different time intervals as mentioned for 24 hours post operatively. Over a period, there is significant difference between the post-operative DBP, but there is no difference in the DBP between the groups A and B.
Figure 4: Means of Post-operative VAS score
Post-operative VAS (visual analogue scale score) score was recorded and compared between both the groups after the TAP block, at different time intervals as mentioned for 24 hours post operatively. Over a period, there is significant difference between the post-operative VAS score, but shows nil difference in the VAS score in between the groups A and B.
Figure 5: Means of post-operative Ramsay sedation score
Post-operative Ramsay score for sedation were noted and related between both the groups after the TAP block, at different time intervals as mentioned for 24 hours post operatively. Over a period, there is significant difference between the post-operative Ramsay sedation score but there shows, no difference in the sedation score within the groups A and B.
Post-operative opioids requirement:
Post op opioid requirement |
Group A Mean ± SD |
Group B Mean ± SD |
P valve
|
Inj.Tramadol 50mg. I.V |
1.6 ±1.1 |
1.3 ± 1 |
0.325
|
A common practise in multimodal analgesia, transversus abdominis plane block provides pain relief both during and after surgery by blocking the transversus abdominis muscle with the aid of ultrasonography. The duration of analgesia could be prolonged by inserting a catheter in the transversus abdominis plane or by using additives such dexamethasone, clonidine, dexmedetomidine, and magnesium sulphate.
Chad M. Brummet and Brian A. Williams (11), who reviewed the most often employed additives combined with local anaesthetics to extend the time of local anaesthetics, conducted their review. In their opinion, long-acting local anaesthetics (ropivacaine, bupivacaine, and levobupivacaine) should be combined with epinephrine, dexamethasone, midazolam, magnesium sulphate, clonidine, and dexmedetomidine for peripheral nerve blocks.
Sharma et al(12) performed a randomised double-blinded study for comparing the quality and duration of post-op analgesia on addition of 8mg dexamethasone(2ml) to 0.5% of ropivacaine 20ml for Ultrasound guided TAP block for repair of hernia from inguinal canal under spinal anaesthesia in 60 patients against using 0.5% of ropivacaine 20ml with normal saline 2ml in the TAP block. They found significantly positive results in favour of the adjunct of 8mg of dexamethasone to 0.5% of ropivacaine to TAP block with regards to prolongation of duration of analgesia with reduced pain scores and thus reduced post-operative analgesic consumption. They also noted that, addition of dexamethasone does not cause any statistically significant haemodynamic changes to the subjects who received it in their TAP block.
In our study, the results were in congruence with that of Sharma et.al for 8mg dexamethasones to 0.5% ropivacaine and with Qin et al for medium dose of dexmedetomidine (0.5mcgs/kg) to 0.2% ropivacaine in terms of haemodynamic variables.
VAS score
It was observed from the hourly analysis of VAS score that there was statistical significant difference in peri-operative Visual analogue scale scoring at certain time points, specifically at 8 hours with (p value < 0.001), at 9 hrs (p value < 0.001), at 13 hrs (p value < 0.005) and at 14 hours (p value < 0.020) following TAP block between the three study groups.
The research was conducted out on 60 patients who were scheduled for various surgical operations by Hemalata Rajesh Kumar Singh et al13. Comparing the VAS scores of Group RC (ropivacaine with 75 mg of clonidine) and Group RD (ropivacaine with 8 mg of dexamethasone), it was found that Group RC's score was much lower than that of Group RD's. When allegorized to group RD, the analgesia time was substantially longer in RC group (16.50. ± 6.68 vs. 9.67 ±6.46 hr) with P = 0.001. In comparison to group RD, group RC required significantly less rescue analgesia.
As with the studies mentioned above, we found that the addition of adjunct namely 8mg dexamethasone and 75 mcgs clonidine to 0.25% of Ropivacaine in TA Plane block administered significantly extended the pain relief of patient well after surgery when compared to using plain 0.5% ropivacaine.
Clonidine as an additive to 0.25% of ropivacaine offered a significantly longer duration of pain relief when compared to dexamethasone in our study and reduced the requirement of opioid post operatively.
Limitations:
Examples of non-research factors that could affect the findings include technical difficulties, different anaesthesiologists performing TAP blocks for each case, and different operating surgeon.
The addition of intrathecal opioid could make it difficult for the patient to assess their pain using a visual analogue scale after recovery since the sensory numbness from spinal anaesthesia and TAP block may overlap. This study’s primary outcome was the duration, that the patient is free from pain which was determined by the mean time between the delivery of the TAP block and patient request for the first rescue analgesic.
According to the outcomes of our study, clonidine is significantly more advantageous than dexamethasone as an additive to 0.25% of ropivacaine using an ultrasound-guided TAP blocks in TAH patients. In comparison to the addition of dexamethasone (8 mg), addition of clonidine (75 mg) provided better and more lasting postoperative analgesia.
CONFLICTS OF INTEREST: NONE