Brazilian Journal of Anesthesiology 2021;71(4):358---366 CLINICAL RESEARCH Paravertebral block using levobupivacaine or dexmedetomidine-levobupivacaine for analgesia after cholecystectomy: a randomized double-blind trial a a a a,∗ b Indu Mohini Sen , K. Prashanth , Nidhi Bhatia , Nitika Goel , Lileswar Kaman a Post Graduate Institute of Medical Education and Research (PGIMER), Department of Anaesthesia, Chandigarh, India b Post Graduate Institute of Medical Education and Research (PGIMER), Department of General Surgery, Chandigarh, India Received 8 August 2019; accepted 22 November 2020 Available online 10 February 2021 KEYWORDS Abstract Laparosopic Background: Thoracic paravertebral block (TPVB) has emerged as an effective and feasible cholecystectomy; mode of providing analgesia in laparoscopic cholecystectomy. Though a variety of local anaes- Thoracic thetic combinations are used for providing TPVB, literature is sparse on use of dexmedetomidine in TPVB. We aimed to compare levobupivacaine and levobupivacaine-dexmedetomidine combi- paravertebral block; Levobupivacaine; nation in ultrasound guided TPVB in patients undergoing laparoscopic cholecystectomy. Dexmedetomidine; Methodology: 70 ASA I/II patients, aged 18---60 years, scheduled to undergo laparoscopic chole- Postoperative cystectomy under general anaesthesia were enrolled and divided into two groups. Before analgesia anaesthesia induction, group A patients received unilateral right sided ultrasound guided TPVB with 15 ml 0.25% levobupivacaine plus 2 ml normal saline while group B patients received uni- lateral right sided ultrasound guided TPVB with 15 ml 0.25% levobupivacaine plus 2 ml solution -1 containing dexmedetomidine 1 ␮g.kg . Patients were monitored for pain using Numeric Rating Scale (NRS) at rest, on movement, coughing and comfort scores post surgery. Total analgesic consumption in first 48 hour postoperative period, time to first request analgesic and pain scores were recorded. Results: Total amount of rescue analgesia (injection tramadol plus injection tramadol intra- venous equivalent dose) consumed during 48 hours postoperatively in group A was 146.55 mg while in group B was 111.30 mg (p = 0.026). Mean time for demanding rescue analgesia was 273 minutes in group A while in group B was 340 minutes (p = 0.00). -1 Conclusion: TPVB using dexmedetomidine 1 ␮g.kg added to levobupivacaine 0.25% in patients undergoing laparoscopic cholecystectomy significantly reduced total analgesic consumption in first 48 hours and provided longer duration of analgesia postoperatively compared to levobupi- vacaine 0.25% alone. © 2021 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/ by-nc-nd/4.0/). ∗ Corresponding author. E-mail: [email protected] (N. Goel). https://doi.org/10.1016/j.bjane.2021.02.018 © 2021 Sociedade Brasileira de Anestesiologia. Published by Elsevier Editora Ltda. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Brazilian Journal of Anesthesiology 2021;71(4):358---366 Introduction levobupivacaine plus 2 ml normal saline, while in group B, patients received unilateral right-sided ultrasound guided thoracic paravertebral block with 15 ml 0.25% levobupi- Laparoscopic cholecystectomy is one of the most com- vacaine plus 2 ml solution containing dexmedetomidine monly performed surgeries in gall ball disease patients. A ␮ -1 1 g.kg . large number of patients undergoing laparoscopic chole- cystectomy may suffer from severe postoperative pain if 1 analgesia is not managed appropriately. The presence of Blinding acute postoperative pain causes extreme patient discom- fort, extended post-anesthesia care unit stays and restricts Both the participants and the investigators were blinded early recovery that should have been seen in laparoscopic to the medications used for the PVB until the comple- surgeries. Over the past years, paravertebral blocks (PVB) tion of study. All the investigators involved in patient’s have been increasingly used for providing postoperative management and data collection, including the patient’s 2 analgesia. The use of ultrasound in the administration anesthesiologist giving general anesthesia, were unaware of of thoracic paravertebral block has greatly reduced the the group assignment. 3 incidence of associated complications. There are reports in literature describing the use of TPVB for providing 4,5 Procedure post-laparoscopic cholecystectomy analgesia. Though a variety of local anesthetics have been used for admin- In the preoperative room, patients were monitored for heart istering TPVB, there is scarcity of studies on adjuvants rate (HR), blood pressure (BP), continuous electrocardio- in thoracic paravertebral block in laparoscopic cholecys- gram (ECG) and arterial oxygen saturation (SpO2) using tectomy. Hence the present trial was designed to assess standard monitors. Baseline readings were recorded, and additional analgesic requirement in patients undergoing an intravenous access was established in all patients. All laparoscopic cholecystectomies after preoperative unilat- the patients were premedicated with intravenous mida- eral thoracic PVB using two different analgesic combinations -1 -1 zolam 25 ␮g.kg , ranitidine 1 mg.kg and palanosetron (levobupivacaine vs. levobupivacaine and dexmedetomidine -1 1 ␮g.kg . To perform the block, patients were placed in combination). We hypothesized that adding dexmedetomi- sitting position and spinous process of T8 vertebra was iden- dine to levobupivacaine would reduce the postoperative tified and marked. Under aseptic precautions, using a sterile analgesic consumption and increase the time to first rescue analgesic. high-frequency (5---10 MHz) ultrasound probe (Sonosite, Inc. Bother. Wa 98021 USA), the thoracic paravertebral space 6 was identified. After infiltrating the skin with 3 --- 5 ml of Methodology 1% lignocaine, in-plane needle guidance technique was fol- lowed using a 20G epidural needle on unilateral right side. Ethics Once the tip of the needle was in a position between the internal intercostal membrane and the pleura, the study After obtaining approval from the institutional ethics drug was administered, after negative aspiration over a committee of Post Graduate Institute of Medical period of 30 seconds. During administration of the local Education and Research, Chandigarh (9171/INT/IEC/PG- anesthetic, downward displacement of the parietal pleura 2Trg/2012/22034), dated November 20, 2013, this was observed. Patient’s hemodynamics were monitored for prospective, randomized, double-blind trial was car- a period of 20 minutes after giving the block. Following ried out by the Department of Anesthesia & Intensive Care this, patients were shifted to operating room. In the oper- and Department of General Surgery of the institute. ating room, patients were monitored for heart rate (HR), blood pressure (BP), continuous electrocardiogram (ECG), arterial oxygen saturation (SpO2), end-tidal carbon diox- Inclusion and exclusion criteria ide (ETCO2) and temperature using multichannel monitors (Datex-Ohmeda S/5 Avance). General anesthesia in all the After obtaining written informed consent, 70 ASA (American participants followed a standard anesthetic technique. After Society of Anesthesiologists) I/II patients, aged 18---60 years, preoxygenation with 100% oxygen, anesthesia was induced scheduled to undergo laparoscopic cholecystectomy under -1 -1 with injection fentanyl 1.5 ␮g.kg and propofol 2 --- 3 mg.kg . general anesthesia were enrolled in the study. Patients -1 Atracurium 0.5 mg.kg was given to facilitate tracheal intu- with history of allergy to local anesthetics, coagulopathy, bation. The maintenance of anesthesia was provided with morbid obesity and having decreased pulmonary reserve, oxygen and isoflurane. The patients received top-ups of cardiac disorders, renal dysfunction, pre-existing neurologi- -1 intravenous atracurium (0.1 mg.kg ) at regular intervals cal deficits, psychiatric illness were excluded from the study. 7 using TOF. Heart rate and mean arterial pressure were maintained within 20% of the baseline values by the adminis- -1 Randomization tration of additional bolus doses of fentanyl (0.5 ␮g.kg ), if required, and the amount of additional intravenous fentanyl Patients were randomized using coded sealed envelopes consumed intraoperatively was noted. At the end of surgery, computer generated, and subsequently participants were 500 ml normal saline was used for the intraperitoneal irriga- allocated to one of the two groups of 35 patients each. tion in all the patients, and residual neuromuscular blockade -1 In group A, patients received unilateral right-sided ultra- was reversed with injection neostigmine 50 ␮g.kg and -1 sound guided thoracic paravertebral block with 15 ml 0.25% injection glycopyrrolate 10 ␮g.kg , and local anesthetics 359 I.M. Sen, K. Prashanth, N. Bhatia et al. were not infiltrated in trocar sites. On return of conscious- parametric data (age, height, weight) were analyzed using ness and adequate recovery of muscle strength, patients the independent samples t-test, while the non-parametric were extubated and shifted to the postanesthetic care unit data were analyzed using Mann-Whitney U test. Continu- (PACU). ous data like heart rate and blood pressure were analyzed by repeated measure ANOVA after checking the normal dis- tribution. Within group analysis of hemodynamic