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1 DOI:.6/aimdr...S. Original Article ISSN (O:9-; ISSN (P:9- Comparative, Randomized, Prospective, Double Blinded, Evaluation of Epidural Ropivacaine with Dexmedetomidine or Fentanyl as Adjuvants in Patients Undergoing Total Abdominal Hystrectomy. Chittra, Ravi Kant Dogra, Ajay Sood, Shyam Bhandari, Aman Thakur, Pooja Gurnal Senior Resident, Department of Anaesthesia, Dr RPGMC, Kangra. Associate Professor, Department of Anaesthesia, IGMC, Shimla. Professor, Department of Anaesthesia, IGMC, Shimla. Assistant Professor, Department of Anaesthesia, Dr RPGMC, Kangra. Senior Resident, Department of Anaesthesia, Dr RPGMC, Kangra. ABSTRACT Background: Epidural is a versatile neuraxial anesthetic technique with an expanding area of indications. Fentanyl is an established adjuvant to be used in epidural for prolonging analgesia. Dexmedetomidine, a newer α agonist exhibits synergism with local anesthetics in epidural,prolonging the sensory/motor block duration time and postoperative analgesia.we compared fentanyl with dexmedetomidine in epidural anesthesia along with ropivacaine in infraumbilical surgeries regarding efficacy and side effects. Methods: The study was conducted in ASA, I-II patients aged between -7 years for total abdominal hysterctomy. Group (FR received Ropivacaine.7%, ml + Fentanyl µg /kg and Group (DR received Ropivacaine.7%, ml + Dexmedetomidine µg /kg in single shot epidural anesthesia. They were evaluated for onset of sensory and motor block, hemodynamics, total duration of analgesia and motor block and any side effects associated with it. Results: Demographic profile and baseline hemodynamic parameters were comparable in both groups. Mean onset of sensory block (min in group FR was 9.76 ±.69 & in group DR was 7.9 ±.9 (p<.. Mean total duration of sensory block was.66 ± 66. (min in FR group whereas. ± 66.7 (min in DR group (p<..mean total duration of motor block was 9. ±. min in FR group and. ±.66 min in DR group (p<.. Conclusion: Dexmedetomidine when added to ropivacaine as adjunct in epidural anesthesia provides better analgesia, good operating conditions and excellent sedation profile. Keywords: Epidural, Anesthesia, Adjuvant, Ropivacaine, Fentanyl, Dexmedetomidine. INTRODUCTION Advances in perioperative analgesia and anesthesia have improved pain relief and satisfaction in surgical patients. Regional anesthesia is continuously evolving since its inception. Epidural is a versatile neuraxial anesthetic technique with an expanding area of indications. Typically its use has been limited to procedures involving lower abdomen, perineum, pelvis and lower limb surgeries but now with the advent of new techniques and equipments even neck, upper abdominal and thoracic surgeries are being performed with ease. It may be used either as sole anesthetic or to supplement general anesthesia or to provide postoperative pain relief. As part of a multimodal analgesia, epidural analgesia can enhance the quality of patient recovery from major surgery and shorten hospital stay. Patients also benefit from decrease in post operative nausea vomiting, paralytic ileus, along with less likelihood of anastomotic leakage leading to early mobility and hence less post operative mortality. [,] Name & Address of Corresponding Author Dr Ravi Kant Dogra, Associate Professor, Department of Anaesthesia, IGMC Shimla,. In epidural anesthesia, primary site of action is spinal nerve roots [] & achievement of optimal anesthesia and analgesia depends on choice of agent. These agents can be local anesthetics alone or local anesthetics with adjuvants. Hence it is important to consider properly the specific properties of a local anesthetic, its concentration, side effects, relative efficacy and potency as compared with other drugs. Potential for less cardiotoxicity and early evidence suggesting motor block produced by ropivacaine of less intensity and of lesser duration than bupivacaine, have led to its extensive evaluation in epidural block. [] In low concentrations, ropivacaine appears to have a differential sensory/motor block with a degree of motor sparing, although this disappears with the higher concentrations that are capable of providing a dense motor block. [] Various drugs have been used as neuraxial block adjuvants like opioids, adrenergic, NMDA receptor antagonists, midazolam, tramadol and cholinesterase inhibitors. As a neuraxial adjuvant, α adrenoceptor agonist s main site for antinociceptive effect in physiological pain seems to be the spinal dorsal horn. Dexmedetomidine is a new generation α agonist which shows more α selective properties. Epidural anaesthesia has been been associated with more stable hemodynamics along with provision for prolongation of intraoperative and postoperative analgesia when compared with spinal anaesthesia. At Annals of International Medical and Dental Research, Vol (, Supplement (November Page 6

2 the same time, epidural anaesthesia also avoids complications related to dural puncture. As not much of literature is available for comparison of fentanyl with dexmedetomidine as adjuvants in epidural anesthesia with local anesthetic regarding efficacy and side effects, we intended comparing fentanyl with dexmedetomidine in epidural anesthesia along with ropivacaine in infraumbilical surgeries. MATERIALS AND METHODS This study was conducted in 6 ASA, I-II patients aged between -7 years undergoing Total Abdominal Hysterectomy under department of anesthesia at Indira Gandhi Medical College, Shimla in a controlled, prospective, randomized manner. Block randomization was done using computer generated numbers. Exclusion criteria included history of reactions to amide local anesthetic, fentanyl or dexmedetomidine, hematological diseases, bleeding or coagulation abnormalities, local sepsis, spinal deformities, noncooperation and unwillingness of patient. During preanaesthetic visit, the patients were explained about the study purpose, advantages and instructed to demand analgesia as per requirement and informed written consent was obtained. Monitoring was started with pulse oximetry, heart rate, arterial blood pressure and electrocardiogram. Intravenous infusion using -gauge cannula was established with crystalloid fluids. With the patient in sitting position, L-L intervertebral space was identified. Under all aseptic conditions skin was infiltrated with ml of % lignocaine, -gauge Tuohy epidural needle was inserted and epidural space was identified using loss of resistance to saline. Epidural catheter was inserted and fixed at additional cm into epidural space. Test dose of ml of % lignocaine containing :, epinephrine was administered to detect intravascular or intrathecal injection. Three minutes later, patients of group FR received single shot epidural dose of ml of.7% ropivacaine along with fentanyl µg /kg whereas group DR received ml of.7% ropivacaine with µg /kg of Dexmedetomidine, given slowly. The speed of epidural drug administration was constant around ml/sec. Procedure was abandoned if dura was punctured, general anaesthesia was given and patient was not included in study. If effect was patchy and additional general anesthesia was required, it was also counted as failure. All the assessments were done by same observer who was blinded to the type of group to minimize any observer dependent variations. Onset of sensory block level was assessed from the time of injecting drug into epidural space till complete analgesia at the level of lower border of umbilicus (T. Level of sensory block was checked bilaterally by pin-prick method (-gauge hypodermic needle.the onset of motor block was assessed at every minute interval till complete motor blockade (Grade Ш was achieved as per Modified Bromage Scale. Hemodynamics and oxygen saturation was measured after every minute for first minutes, every minutes for next minutes, every minutes for next minutes and then after every minutes till completion of surgical procedure. Side effects, if any were reported and treated upon. At, and 6 minutes after epidural sedation levels were assessed as per Ramsay sedation score (Table V. Post operative pain was assessed by visual analogue scale (VAS which ranges from -. First top-up through epidural catheter for pain was given corresponding to VAS score equal or more than. Primary outcome of this study was total duration of analgesia. Secondary outcome was time to onset of sensory and motor blockade, hemodynamic alterations, sedation levels and side effects associated with it. Data was collected and entered in MS Excel 7. Data was analyzed using Paired t test, ANOVA and Mann Whitney U test and categorical data was analysed using the Chi square test. P<. was considered statistically significant & p values less than. were considered to be highly significant. RESULTS All the patients in both the groups were comparable in terms of demographic profile and baseline hemodynamic parameters [Table ]. There was statistically significant difference in onset of sensory block in FR group as compared to the DR group with values as 9.76 ±.69 & 7.9 ±.9 minutes respectively [Table ]. Time taken for onset of motor blockade was also found statistically significant being. ±.6 & 6. ±.77 minutes in group DR and FR respectively (p<. [Table ]. Two segment sensory regression was slower in DR group as compared to FR group being ±.77 &. ± 9.9 minutes respectively (p<.. Total duration of analgesia was significantly longer in DR group in comparison with FR group being. ± 66.7 &.66 ± 66. minutes respectively [Table ]. Statistically significant difference was observed in sedation levels at, and 6 minutes after administering epidural [Table, Figure ]. At 6 min, most (6.7% of the patients in group DR had sedation grade of and group FR had grade of. In all time periods, DR group exhibited higher sedation levels (p<.. No statistically significant difference was seen in SBP, DBP and MAP in both the groups, though fall in blood pressure was noted and maximum was around -6 minutes [Figure,, respectively]. Decline in heart rate was noted in both the groups, maximum at -6 minutes after giving epidural. The difference was statistically significant (p<., with more decrease in heart rate in DR group [Figure 6]. There was high incidence of Annals of International Medical and Dental Research, Vol (, Supplement (November Page 7

3 pruritus (6.67% in FR group whereas none of the patient had pruritus in group DR [Table 6]. Table : Demographic profile, baseline parameters of patients undergoing surgery in our study. Parameter FR DR Age ( Mean ± S.D.6 ±..6 ±.7 Body mass index(bmi 9. ±.. ±. Duration of surgery ( min 6.±. 6 ±. Type of surgery 6 Vaginal Hystrectomy Abdominal Hystrectomy SBP ( mmhg.6 ± 9..6 ±. DBP 7. ± 9..6 ±. MAP 99. ±.7. ±.9 Heart Rate( per min.6 ±. 9.9 ±.9 SPO 97.6 ± ±. Table : Sensory and motor block characteristics in group FR and group DR Parameter P value Onset of 9.76 ± ±.9.** sensory block Onset of motor. ±.6 6. ±.77.** block Time to 6. ±.. ±.. ** achieve maximum level Two segment. ± ±.77.** regression time 9.9 Total sensory.66 ±. ±.* duraion 66. Total motor block duration **- highly significant 9. ± ±.66.** Table : Highest Sensory Dermatomal Level. Paramete T T (n T (n T6 (n p-value r (n Group FR (% (.% (6.66% 6 (%.6* * Group DR (% **- highly significant No. of patients 6 (6.66% 6 (% (.% T T T T6 6 6 Figure : Comparison of highest sensory dermatomal level. Table : Sedation Levels in group FR and 6 p value min (n.** (% (n (% min (n.** (% (% (n (6% (% 6 min (n (6.6% (6.7%.** (6.7% (n (.% (6.7% ** highly significant (n (n (n (n (n (n min min 6 min 6 Figure : Comparison of Sedation Levels Annals of International Medical and Dental Research, Vol (, Supplement (November Page

4 Figure : Intergroup comparison of systolic blood pressure (mmhg Figure : Intergroup comparison of Diastolic blood pressure (mmhg Figure : Intergroup comparison of Mean Arterial Pressure (mmhg. Annals of International Medical and Dental Research, Vol (, Supplement (November Page 9

5 Figure 6: Intergroup Comparison of Heart Rate (bpm. Table : Ramsay sedation scale used in our study. Patient is anxious and agitated or restless, or both Patient is cooperative, oriented and tranquil Patient responds to commands only Patient exhibits brisk response to light glabellar tap or loud auditory stimulus Patient exhibits a sluggish response to light glabellar tap or loud auditory stimulus 6 Patient exhibits no response Table 6: Complications in first hours. Side Effects Pruritis Hypotension ( requiring treatment with inj mephentramine Bradycardia Shivering 6 Nausea Vomiting Dry mouth DISCUSSION Use of regional anesthetics for any kind of procedural pain has become a nearly universal phenomenon. Epidural techniques are particularly effective at providing dynamic analgesia, allowing the patient to mobilize and resume normal activities limited by pain with better respiratory, cardiovascular, gastrointestinal and cognitive outcomes. [6-] This is usually and most commonly achieved with a combination of epidural local anesthetic and an adjuvant. One of the major advantages of plain epidural is avoidance of dural puncture which will avoid postdural puncture headache (PDPH. Several researchers across the world have tried various combinations of local anesthetics and adjuvants in epidural space in order to find the best ones. Hence, in our study we compared efficacy of ropivacaine with fentanyl and dexmedetomidine in epidural space to provide adequate anesthesia and analgesia. The results of our study show that the onset of sensory block was significantly shorter for group DR (7.9 ±.9 minutes as compared to group FR (9.76 ±.69 minutes, p<.. This result is corroborated by many other authors. [9-] Onset of attainment of modified Bromage scale III was significantly faster in group DR than group FR. Median value for highest sensory dermatomal level achieved in group DR was T, being present in % patients whereas none of the patients in group FR achieved value of T [Table, Figure ]. Median value for highest sensory dermatomal level achieved in group FR was T which was present in.% patients. Our study hence concludes that higher sensory levels are achieved by dexmedetomidine as an adjuvant to local anesthetic ropivacaine in epidural in comparison to Fentanyl. Our study showed that regression of sensory level was prolonged in DR group than FR group. Results of our study showed that total duration of sensory block was significantly longer in group DR as compared to group FR being. ± 66.7 minutes &.66 ± 66. minutes respectively. Sensory and motor levels onset, regression and total duration observed in our study were almost similar with studies done by Bajwa et al, Salgado et al, Saravanababu et al and Christelis N et al. [9-] Annals of International Medical and Dental Research, Vol (, Supplement (November Page 6

6 In group DR most of the times, patients were responding either to physical stimulus or loud sounds whereas in group FR patients were conscious enough to respond to verbal commands. Despite profound sedative properties, dexmedetomidine is associated with only limited respiratory effects, leading to a wide safety margin. [-] In our study, there was decline in systolic, diastolic as well as mean arterial blood pressures in both the groups from baseline. Maximum decline was seen in between minutes, after that it became stabilized. There was no statistically significant difference in blood pressure values in both the groups throughout surgery. Dexmedetomidine with low and clinically recommended concentrations leads to hypotension caused by a centrally mediated sympatholysis and by the inhibition of neurotransmission in sympathetic nerves. [] HR in both the groups had shown a falling trend initially and stabilizing after around 7 minutes. There was statistically significant difference in both the groups in HR at 6 minutes, with dexmedetomidine group exhibiting comparatively more decline. This could be due to the fact that dexmedetomidine possesses a dose-dependent bradycardiac effect, mediated primarily by the decrease in sympathetic tone and partly by baroreceptor reflex and enhanced vagal activity. [6] In our study, side effect profiles were different among both the groups. Pruritus was main side effect seen in group FR and was present in (6.67% patients, though it didn t require any treatment. All affected patients had pruritus localized to nasal region only. Side effects like hypotension, bradycardia, nausea, vomiting, shivering, dry mouth or any other side effect in either group were clinically not significant in first hours as shown in Table 6. Urinary retention could not be assessed as all the patients were catheterized in first hours. CONCLUSION Hence, we conclude that dexmedetomidine when added to ropivacaine as adjunct in epidural anesthesia is a better option than fentanyl in terms of prolonged and better analgesia, good operating conditions, excellent sedation profile & similar stable cardio-respiratory parameters. But, larger trial of similar drugs should be undertaken before accepting or refuting this study. REFERENCES. Kehlet H, Holte K. Effect of postoperative analgesia on surgical outcome. Br J Anaesth ;7: Moraca RJ, Sheldon DG, Thirlby RC. The Role of Epidural Anesthesia and Analgesia in Surgical Practice. Ann Surg.;(: Simon MJG, Veering BT. Factors affecting the pharmacokinetics and neural block characteristics after epidural administration of local anaesthetics. European Journal of Pain Supplements.;9-.. Whiteside JB, Wildsmith JAW. Developments in local anaesthetic drugs.br J Anaesth.7;7-.. Mclure HA, Rubin AP. Review of local anesthetic agents. Minerva Anestesiol ;7: Kehlet H, Holte K. Effect of postoperative analgesia on surgical outcome. Br J Anaesth ;7: Moraca RJ, Sheldon DG, Thirlby RC. The Role of Epidural Anesthesia and Analgesia in Surgical Practice. Ann Surg.;(: Nimmo MS. Benefit and outcome after epidural analgesia. ContinEducAnaesthCrit Care Pain.;(:-7 9. Salgado PFS, Sabbag AT, Da Silva PC, Brienze SLA, Dalto HB, Pinheiro MNS, Braz JRC, Birth P. Synergistic effect between dexmedetomidine and.7% ropivacaine in epidural anesthesia. Rev Assoc Med Bras. ;(:-.. Bajwa SJS, Bajwa SK, Kaur J, Singh G, Arora V, Gupta S, Kulshrestha A, Singh A, Parmar SS, Singh A, Goraya SPS. Dexmedetomidine and clonidine in epidural anaesthesia: A comparative evaluation.indian J Anaesth. ;:6-.. Bajwa SJS, Arora V, Kaur J, Singh A, Parmar SS. Comparative evaluation of dexmedetomidine and fentanyl for epidural analgesia in lower limb orthopedic surgeries. Saudi J Anaesth. ;:6-7.. SaravanaBabu MS, Verma AK, Agarwal A, Tyagi CM, Upadhyay M, Tripathi S. A comparative study in the postoperative spine surgeries: Epidural ropivacaine with dexmedetomidine and ropivacaine with clonidine for postoperative analgesia. Indian J Anaesth ;7:7-6.. Christelis N, Harrad J, Howell PR. A comparison of epidural ropivacaine.7% and bupivacaine.% with fentanyl for elective caesarean section.int J Obstet Anesth. ;:.. Talke P, Richardson CA, Scheinin M, Fisher DM. Postoperative Pharmacokinetics and Sympatholytic Effects of Dexmedetomidine. AnesthAnalg 997;:6-.. Paris A, Tonner PH. Dexmedetomidine in anaesthesia. CurrOpin Anaesthesiol.;:. 6. Kumar K, Singh SI. Neuraxial opioid-induced pruritus: An update.j Anaesthesiol ClinPharmacol. Jul;9(:-. How to cite this article: Chittra, Dogra RK, Sood A, Bhandari S, Thakur A, Gurnal P. Comparative, Randomized, Prospective, Double Blinded, Evaluation of Epidural Ropivacaine with Dexmedetomidine or Fentanyl as Adjuvants in Patients Undergoing Total Abdominal Hystrectomy. Ann. Int. Med. Den. Res. ;(S:6-6. Source of Support: Nil, Conflict of Interest: None declared Annals of International Medical and Dental Research, Vol (, Supplement (November Page 6