¹III^rd Year Resident, ²Assistant Professor, ³Professor & HOD, Department of Anaesthesia, Surat Municipal Institute of Medical Education and Research, Surat, INDIA.

Email: bhavikaogariwala@gmail.com

Figure 1: Anatomy

POST-OPERATIVE ASSESSMENT

Pain was assessed by VAS score. Time of first request for Postoperative analgesia when VAS≥4. When VAS≥4 Inj Tramadol 50 mg iv was given and that time was calculated as total Duration of analgesia. Side effects like allergy, nausea, vomiting, bradycardia and hypotension were noted.

VAS Score

Figure 2

VISUAL ANALOGUE SCALE

0--------------------2--------------------4-------------------6--------------------8--------------------10

None annoying uncomfortable dreadful               horrible agonizing

OBSERVATION AND RESULTS

After studying 54 cases, observation and results were summarized in tabulated form and described below. Both groups comprised of 27 patients.

Demographic Profile

Table 1:

No significant difference seen in age, weight and duration of surgery among both groups.

All the patients observed among both groups were under ASA grade I/II.

Comparison of pulse and blood pressure in both groups

Pulse and blood pressure of patients were comparable in both groups. Among which no significant difference was observed in either groups for pulse, SBP, DBP at respective pre-operative, intra-operative, post-operative, immediately after TAP block, at 4 hour, at 8 hour, at 12 hour, and at 24 hour.

Post-operative VAS score at rest and on movement (mean SD)

Comparison of VAS score AT REST in both study groups

Pain score (VAS) at rest, at 4 hours, 8 hours, 12 hours, 24 hours timeline expressed as mean ± SD

Table 2:

Figure 3:

Comparison of VAS score AT MOVEMENT in both study groups

Pain score (VAS) at movement, at 4 hours, 8 hours, 12 hours, 24 hours timeline expressed as mean (SD)

Table 3:

Figure 4:

During first 4 hour, no statistical difference was observed in both groups, but after that Pain scores at rest and at movements were lower in patients who received TAP block with levobupivacaine with dexmedetomidine(Groups B) as compared to patients who received TAP block with levobupivacaine alone (Group A).

Total duration of post operative Analgesia supplement and time of first rescue analgesia in mins (mean SD)

Table 4:

Figure 5: Comparison of total duration of Post-operative analgesia in both study groups

Time for first rescue of analgesia and total duration of postoperative analgesia were significantly longer in patients who received TAP block with Levobupivacaine with dexmedetomidine (Groups B) as compared to patients who received TAP block with levobupivacaine alone (Group A).

Patient satisfaction score (mean SD) at 24 hours

Table 5

Figure 6: Comparison of patient Satisfaction score in both groups

Patient satisfaction scores were significantly higher in patients who received TAP block with levobupivacaine with dexmedetomidine (Groups B) as compared to as compared to patients who received TAP block with levobupivacaine alone (Group A).

DISCUSSION

The transversus abdominis plane (TAP) block is a simple, effective, rapidly expanding analgesic technique which significantly reduces pain associated with lower abdominal surgery where parietal pain is a significant component of postoperative pain. It involves a single large bolus injection of local anaesthetic into the TAP, an anatomical space between the internal oblique and transversus abdominis muscles. The local anaesthetic agents in TAP block provides excellent analgesia to the skin and musculature of the anterior abdominal wall. In present study, we compared Levobupivacaine and levobupivacaine with dexemedetomidine in transeversus abdominis plane block for caesarean delivery for postoperative analgesia. The prolonged duration of analgesia after TAP block may be related to the fact that transversus abdominis plane is relatively poorly vascularized, so drug clearance may be slow by reduction of absorption in to the blood stream and less risk of systemic toxicity from the local anaesthetics ^[2]. In this study we demonstrated that by giving bilateral TAP block with 20 ml of 0.25% levobupivacaine with 0.5µg/kg dexmedetomidine on each side in patients undergoing caesarean section, reduced pain score postoperatively and also decreased requirements of postoperative analgesia as compared to patients received bilateral TAP block with same volume of levobupivacaine alone. Various adjuvants have been used to improve the quality and the onset of action of local anaesthetic action in different regional block techniques. Dexmedetomidine, a highly selective, alpha-2-adrenergic receptor (α2-AR) agonist, used by anaesthetists in many anaesthetic techniques due to its hemodynamic-stabilizing properties and sedative, analgesic, and sympatholytic effects to local anaesthetic action. Individual patient characteristics such as age, gender, and body weight are important factors influencing any pharmacologic therapy. All the demographic parameters were comparable in both the groups and there was no statistically significant difference between two groups (p value > 0.05). The mean duration of surgery in Group A was 53.18 ± 5.18 min and 52.51 ± 4.70 min in Group B, which was comparable in both the groups in our study. There was no statistically significant difference regarding duration of surgery in both the groups (p value > 0.05). In present study, hemodynamic parameters observed were mean pulse rate, mean systolic blood pressure, mean diastolic blood pressure. No significant difference was observed in both the groups (p value > 0.05). This study correlate with P. Raghunath et al.³ , Aman Varshney et al.. ^[1] , in 2015 Abdelaal et al.⁴ studies suggesting that no significance difference found in mean pulse rate, mean systolic blood pressure, mean diastolic blood pressure. Postoperative pain assessment was done by Visual Analogue Scale (VAS) score for 24 hours. In our study, In Group A, mean VAS score at rest appeared to rise from the 9th hour and at movements appeared to rise from the 7^th hour, while in Group B, mean VAS score at rest remained < 3 at 24^thhour and at movements appeared to rise from the 15^th hour postoperatively. There was statistically highly significant difference in postoperative mean VAS score between both the groups postoperatively (p value > 0.001). Xiao F, Liu L, Xu W, et al.⁶ conducted a study titled “Dexmedetomidine can extend the duration of analgesia of levobupivacaine in transversus abdominis plane block”. Patients in the Control group (n = 30) received TAP block, using 40 mL of 0.25% levobupivacaine, and patients in the Dexmedetomidine group (Dex group) received the same volume and concentration of levobupivacaine but with additional 0.5 µg/kg of dexmedetomidine for TAP block. The VAS point at rest was significantly lower in the Dex group than in the Control group at 8 and 12 hours (P < 0.05). The patient satisfaction with postoperative analgesia in the Dex group was better than in the Control group (P = 0.006). The duration of analgesia was significantly longer in the Dex group than in the Control group (905.0 ± 114.2 min vs. 741.4 ± 105.3 min, P < 0.001). Our study data is consistent with this study. Almarakbi WA, Kaki AM¹⁴ conducted a study titled “Addition of dexmedetomidine to bupivacaine in transversus abdominis plane block potentiates post-operative pain relief among abdominal hysterectomy patients”. They observed that addition of dexmedetomidine to bupivacaine in TAP block had significantly lower VAS score at rest and at movement which is consistent with our study. In our study, the mean time for first rescue analgesia in Group A was 522.62 ± 53.24 min (⁓8.7 hr) and in Group B was 977.40 ± 57.80 min (⁓16.2 hr) which was statistically high significant difference (p value < 0.05), with longest in Group B. We added dexmedetomidine in TAP block as adjuvant to levobupivacaine to prolonged the postoperative analgesia duration and we found that addition of dexmedetomidine prolonged the duration of request of first rescue analgesia. Abdelaal et al.⁴in 2015 done comparative study between levobupivacaine versus levobupivacaine plus dexmedetomidine for TAP in postoperative pain management after abdominoplasty. In total of 69 patients, they reported dexmedetomidine (Group M) and levobupivacaine (Group L) group had significant lower pain score as compared to control group. They observed that dexmedetomidine (Group M) and levobupivacaine (Group L) group had significant less consumption of meperidine in comparison to C group with significance of P < 0.001. Postoperatively 24 h total meperidine consumption in M group was less than in L group P < 0.01. Addition of dexmedetomidine in TAP block as an adjuvant prolonged duration of postoperative analgesia which is correlated with our study. Aman Varshney et al.¹ conducted a study titled TAP block with levobupivacaine versus levobupivacaine with dexmedetomidine for postoperative analgesia following cesarean delivery. The time for the first request of analgesia was significantly longer in group D (TAP block with 20 cc 0.25% levobupivacaine +1µg/kg dexmedetomidine on each side) as compared to group L (TAP block with 20 cc 0.25% levobupivacaine on each side) and control group (no TAP block). They observed that addition of dexmedetomidine prolongs the effect till 12 hours which is correlated with our study. P. Raghunath et al.³ conducted a study to compare ropivacaine versus levobupivacaine in TAP for postoperative analgesia in patients undergoing lower abdominal surgeries. Duration of postoperative analgesia in TAP block with 0.25% levobupivacaine was 419.6±49.95 minutes and in TAP block with 0.5% ropivacaine was 2140.6±511.12 minutes (p<0.05). The study data is consistent with our data. Loane et al.¹⁶ found that the use of TAP block did not provide analgesia in comparison with “100 µg morphine” intrathecally in the first 24 h and require higher analgesic consumption due to higher pain score. Costello and colleagues ¹⁵, these investigators found no analgesic benefit from TAP block using ropivacaine 20 ml 0.375 % per side in patients undergoing caesarean section under spinal anaesthesia This is due to TAP block was performed as blind technique. We and them did not use ultrasound to visualize the anatomy, we cannot guarantee
correct placement of the block, it is therefore possible that portion of block were placed incorrectly either superficially or intraperitoneally. 3 patients in the study group had bradycardia (HR< 50) within 15 min of TAP and were given Inj. Atropine 0.6 mg. However, they were hemodynamically stable. No other side effects were noted. Newborns were monitored for the first 24 h after birth for any respiratory depression and bradycardia. None of them required admission to the NICU.

Limitation:

Plasma levels of dexmedetomidine were not monitored. The time at which the TAP block began to work could not be differentiated. The time at which the sensory effect of the intrathecal block began to wear off could not be clearly differentiated.

CONCLUSION

Bilateral TAP block with 0.25% levobupivacaine provides good quality analgesia for early postoperative period. Adding dexmedetomidine further improves pain control and gives higher patient satisfaction without any added side effects.

REFERENCES

• Varshney A, Prabhu M, Periyadka B, Nanjundegowda DC, Rao A. Transversus abdominis plane (TAP) block with levobupivacaine versus levobupivacaine with dexmedetomidine for postoperative analgesia following cesarean delivery. J Anaesthesiol Clin Pharmacol 2019;35:161-4.
• Velchev V, Malamov K (2010) The analgesic efficacy of transversusabdominis plane (TAP) block. Khirurgiia (Sofiia) 1: 15-18.
• P. Raghunath, Tailam Tanmayee, D. Anuradha. Transversus abdominus plane block with ropivacaine vs levobupivacaine for post-operative analgesia in patients undergoing lower abdominal surgeries. International Journal of Contemporary Medical Research 2017;4(11):2245-2249.
• Abdelaal W, Metry AA, Refaat M, Ragaei M, Nakhla G. Comparative study between levobupivacine versus levobupivacaine plus dexmedetomidine for transversus abdominis plane block “tap” in postoperative pain management after abdominoplasty. Enliven: J Anesthesiol Crit Care Med 2015;2:14.
• Yildiz I, Bayir H. Effect of dexamethasone added to levobupivacaine used for TAP block. Hippokratia. 2015;19(3):285.
• Xiao F, Liu L, Xu W, et al. Dexmedetomidine can extend the duration of analgesia of levobupivacaine in transversus abdominis plane block: a prospective randomized controlled trial. Int J Clin Exp Med. 2017;10:14954–14960
• F. Bonnet, J. Berger, C. Aveline, Transversus abdominis plane block: what is its role in postoperative analgesia?, BJA: British Journal of Anaesthesia, Volume 103, Issue 4, October 2009, Pages 468–470, https://doi.org/10.1093/bja/aep243
• Srivastava U, Verma S, Singh TK, et al. Efficacy of trans abdominis plane block for post cesarean delivery analgesia: A double-blind, randomized trial. Saudi J Anaesth. 2015;9(3):298–302. doi:10.4103/1658-354X.154732
• Ramya Parameswari A, Udayakumar P. Comparison of Efficacy of Bupivacaine with Dexmedetomidine Versus Bupivacaine Alone for Transversus Abdominis Plane Block for Post-operative Analgesia in Patients Undergoing Elective Caesarean Section. J Obstet Gynaecol India. 2018;68(2):98–103. doi:10.1007/s13224-017-0990-7
• Bansal P, Sood D. Effect of dexmedetomidine as an adjuvant to ropivacaine in ultrasound-guided transversus abdominis plane block for post-operative pain relief in cesarean section. J Obstet Anaesth Crit Care 2018;8:79-82
• Acharya R, Baksi R, Mohapatra P. Comparative analysis of duration of postoperative analgesia between levobupivacaine and levobupivacaine with clonidine after ultrasound-guided transversus abdominis plane block in patients undergoing lower segment cesarean section. Anesth Essays Res 2018;12:943-8
• Masuki S, Dinenno FA, Joyner MJ, Eisenarch JH (2005) Selective alpha 2 – adrenergic properties of dexmedetomidine over clonidine in
  the human forearm. J Appl Physiol 99: 587-592.
• McDonnell JG, Curley G, Carney J, Bentone A, Costello J, Maharaj CH, et al. The analgesic efficacy of transversus abdominis
  plane block after cesarean delivery: A randomized controlled trial. Anesth Analg 2008;106:186‑91.
• Almarakbi WA, Kaki AM. Addition of dexmedetomidine to bupivacaine in transversus abdominis plane block potentiates post-operative pain relief among abdominal hysterectomy patients: A prospective randomized controlled trial. Saudi Journal of Anaesthesia. 2014 Apr;8(2):161-166. DOI: 10.4103/1658-354x.130683.
• Costello JF, Moore AR, Wieczorek PM, Macarthis AJ, Blaki M, et al. (2009) The transverses abdominis plane block, when used as part of multimodal regimen inclusive of intrahecal morphine does not improve analgesia after caesarean delivery. Reg Anesth Pain Med 34: 586-
  589.
• Loane H, Preston R, Douglas MJ, Massey S, Papsdorf M, et al. (2012) A randomized controlled trial comparing intrathecal morphine with transversus abdominis plane block for post – caesarean delivery analgesia. Int J Obstet Anesth 21: 112-118.