Ultrasound Guided Thoracic Paravertebral Block versus Blind Landmark Technique for Breast Surgery. Does it Really Different?

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Med. J. Cairo Univ., Vol. 84, No. 3, December: 235-24, 216 www.medicaljournalofcairouniversity.net Ultrasound Guided Thoracic Paravertebral Block versus Blind Landmark Technique for Breast Surgery. Does it Really Different? RANDA I. BADAWY, M.D.; SAHAR S. ISMAIL, M.D.; MOHAMED AHMED MANSOUR, M.D. and AHMED M. ALI, M.D. The Department ofanesthesiology, Faculty of Medicine, Cairo University Abstract Background and Aim: Thoracic Paravertebral Block (TPVB) is an effective intraoperative and postoperative technique for surgical anaesthesia and analgesia for breast surgery [1]. It offers a long-lasting effective analgesia with a significant decrease in anaesthetic and analgesic consumption. Ultrasound guidance helps identifying the Paravertebral Space (PVS), needle placement, and to real time monitor the spread of the local anesthetic around nerves which increases the efficacy of the block and minimizes the risk of complications. Methods: A total of 48 adult females, ASA physical status I and III, 18-55 years, patients scheduled for unilateral breast surgery. Patients were randomly assigned into 2 groups of equal size (n=24). : Patients received TPVB using blind land mark technique. : Patients received TPVB using ultrasound guided technique. Objective: The purpose of this study is to determine safety and efficacy of ultrasound guided TPVB versus blind technique in breast surgery. Conclusion: This study demonstrated that the use USguided TPVB is feasible, effective, has a high success rate, and decrease the incidence of complications due to direct visualization of anatomical structures, the needle and spread of local anesthetic. Key Words: TPVB US Breast Local anaesthetic Perioperative pain. Introduction THORACIC paravertebral block is a century old technique used for intra-operative and perioperative pain control as well as acute and chronic non-operative pain [1]. It is a technique of injecting local anaethetic in the vicinity of the thoracic spinal Correspondence to: Dr. Randa I. Badawy, The Department of Anesthesiology, Faculty of Medicine, Cairo University nerve emerging from the intervertebral foramen [2]. Many practitioners, however, remained hesitant to perform thoracic paravertebral block for fear of pneumothorax, it is reported that the risk of it doesn't exceed.5%-1%. The risk of Dural puncture is also reported but it is more common with median approach [3]. Recently with the growth of ultrasound technology, our ability to visualize the pleura and other structures in and around the paravertebral space has fueled a tremendous increased interest in performing thoracic paravertebral block [4]. In the present study, an effort has been made to to determine efficacy and safety of TPVB in breast surgery using (blind technique) versus (ultrasound guided technique). Patients and Methods This study was conducted in accordance with principles of Ethical Committee of Kasr El-Ainy Hospital and Cairo University, from June 214 to September 215. Full written informed consent was obtained from all patients before inclusion in this study. A total of 48 adult female patient scheduled for unilateral breast surgery (biopsy, fibroadenoma resection, simple mastectomy). Written consent obtained from all participants. Patients were divided into 2 groups of equal size (n=24). : Patients recived TPVB using blind land mark technique. : Patients recived TPVB using ultrasound guided technique. 235

236 Ultrasound Guided TPVB versus Blind Landmark Technique for Breast Surgery Inclusion criteria: 1- ASA I-III patients. 2- Age 18-55 years. 3- Elective surgical patients needing unilateral breast surgery (biopsy, resection of fibroadenoma and simple mastectomy). Exclusion criteria: 1- ASA IV or V patients. 2- Infection at the thoracic paravertebral injection site. 3- Coagulopathy disorders. 4- Patient refusal. 5- Has a BMI >35kg m2. 6- Allergic to any drugs in the protocol. Pre-operative assessment: All patients were informed about the study design and objectives as well as tools and techniques. Informed consent had been signed by every patient prior to the study. Patients were randomly allocated to one of two groups by sealed closed envelop technique. Routine preoperative assessment including history taking, clinical examination, and laboratory tests. The age, height, weight and BMI of the patients will be recorded. Monitoring was established (pulse oximeter, electrocardiogram and noninvasive blood pressure). All patients were been sedated with.5mg/kg of midazolam and 2mc/kg fentanyl i.v before anesthesia. They were been randomly assigned to receive an ipsilateral TPVB at T2, T4 and T6 with 3.5ml bupivacaine 5mg/ml and 3.5ml lidocaine 2mg/ml (7ml in each level). After 3 minutes, the surgery will be started after examining the block. Interventions: TPVB will be performed with the patient sitting, shoulders and head relaxed and leaning forward. Blind landmark technique Group (A): After a strict aseptic precautions, a wheal of lidocaine 1% (1ml) is raised at each point marked on the parasagittal line (2.5-3cm lateral to spinous process). A Tuohy needle 18G with a 2cm injection line is used, the needle is advanced through the wheal perpendicular to the skin until the bony resistance of the transverse process is met at a variable depth (2-4cm) depending on the build of the individual. When the transverse process is contacted the needle depth is noted. This will help to predict the depth of contact on the subsequent blocks. The needle is walked off the inferior border of the process and further advanced by approximately 1cm as measured by the needle markings. After gentle aspiration to check for blood, CSF and air, the local anaesthetic 3.5ml bupivacaine 5mg/ml and 3.5ml lidocaine 2mg/ml (7ml in each level) will be administered over a period of 3s. Ultrasound-guided technique Group (B): After surgical disinfection of both cervical-thoracic paravertebral areas and protection of the ultrasound probe and cable with a sterile cover, initial ultrasound scanning of the T2, T4 and T6 paravertebral region at the surgical side was performed. An ultrasound machine (SiemensTM, Acuson X3) a low-frequency ultrasound transducer (CH5-2, 2-5MHz) was used. The ultrasound scaning was performed as follows: Identification of (T2, T4, T6) spinous processes by decrement from C7 (vertebra prominens), positioning of the ultrasound probe at the spinous process of T2, lateral movement until the transverse process is visible, and oblique movement until the typical double layer of the Internal Intercostal Membrane (IIM), the transverse process, and the pleura are visualized in one image. The block was performed after skin infiltration with lidocaine 1% (1ml). An in-plane approache was performed. (B. Braun, Stimuloplex Ultra, 22G & 12mm) a 2cm injection line used. Once the tip of the needle in a position between the Internal Intercostal Membrane (IIM), and the pleura, 3.5ml bupivacaine 5mg/ml and 3.5ml lidocaine 2mg/ml (7ml in each level) will be administered over a period of 3s after negative aspiration. During administration of the local anaesthetic, an anterior displacement of the pleura (downward movement) was observed. Monitoring and data collection: Intraoperative: Hemodynamic measurement: (Bl.p and pulse) was taken just after assessment of the block and every 15min throughout surgery. Analgesic consumption: Recorded during intraoperative period to maintain maximum 2% change of basal vital signs after exclusion of other causes. Postoperative: Pain score: VAS score at 2, 6, 12h post-operative. Postoperative nausea and vomiting: PONV scores (categorical scale: =none, 1=nausea, 2=nausea reaching vommiting) was documented.

Randa I. Badawy, et al. 237 Rescue analgesia: Time of the first rescue analgesia was recorded. VAS >4 was given nonsteroidal antiinflammatory analgesic (ketorolac 3mg). Monitoring of other side effects of local anesthetics: Respiratory depression (respiratory rate <8 breath/min, and SpO 2 <9% on the room air). Nausea and vomiting were managed by IV injection of 1mg metoclopramide. Primary outcome: - Number of patients with a technique failure of the TPVB. - Intraoperative hemodynamic changes. - Intra-operative analgesic requirement. Statistical analysis: Data were coded and entered using the statistical package SPSS (Statistical Package for the Social Science; SPSS Inc., Chicago, IL, USA) Version 22. Data was summarized using mean, standard, median, minimum and maximum in quantitative data and using frequency (count) and relative frequency (percentage) for categorical data. Comparisons between groups were done using the non-parametrical Mann-Whitney test (Chan, 23a) [5]. For comparing categorical data, Chi square (χ 2 ) test was performed. Exact test was used instead when the expected frequency is less than 5 (Chan, 23b) [6]. s less than.5 were considered as statistically significant. Results Forty eight patients were enrolled in this study in Kasr El-Ainy-Hospital Cairo University (June 214 to September 215). Patient's characteristics including age, Body Mass Index (BMI), and ASA score are demonstrated in (Tables 1,2). There was no significant difference in the demographic data of the two groups of the study. In mean age was 33.83, in the mean age was 35.87. In mean (BMI) was 29.83, in the mean BMI was 29.96. The primary outcome of this study was faild block in 1 cases and sucss block in 38 cases. In there were 8 cases of faild block and 16 cases of sucss block. In there were 2 cases of faild block and 22 cases of sucss block. And this was significantly different as shown in (Table 3). There were significant differences between the 2 groups in the intraoperative vital signs (blood pressure and pulse rate) and total intraoprative fentanyl dose (Table 6). Comparing the pain score (visual analogue score) of the two groups at 2, 6 and 12hr postoperatively revealed that there was a significant difference in analgesic effect between two groups as showen in Fig. (1). As regard the time of 1 st rescue of analgesia. There was a significant difference between two groups (Table 5). There was higher incidence of post-operative nausea and vomiting in as shown in (Table 6). (Categorical scale: =none, 1=nausea, 2=nausea reaching vommiting). There were no recorded complications in both groups either intra or postoperatively in the form of hemodynamic instability, injury to underlying structures, hematoma formation, inadvertent vascular puncture, pleural puncture and pneumothorax. Table (1): Age and BMI in both study groups. Age BMI 33.83 29.83 9.67 4.31 Data are given as mean ± SD. BMI: Body Mass Index. is significant <=.5. 35.87 29.96 Table (2): ASA in both study groups. ASA: 1 2 3 Count % Count 9.25 3.95 Table (3): Sucss and faild blocks in both study groups. Count % %.433.993 Outcome: Faild 8 33.3 2 8.3.33 Sucss 16 66.7 22 91.7 Count % 2 83.3 16 66.7.382 3 12.5 7 29.1 1 4.2 1 4.2

238 Ultrasound Guided TPVB versus Blind Landmark Technique for Breast Surgery Table (4): Comparison of average Systolic Blood Pressure (SBP), average Diastolic Blood Pressure (DBP), average pulse rate and total fentanyl dose between both study groups during intra-operative period. Average intraoprative SBP Average intraoprative DBP Average intraoprative pulse rate Total intra oprative fentanyl dose (ug) 1 8 6 4 2 SD SD 2h 6h 12h 13.31 8.55 121.9 8.4.3 77.69 8. 71.5 5.71.28 81.81 6.4 73.14 6.3.1 168.75 51.23 75. 29.88.1 Table (5): Time of first rescue of analgesia of both groups. First rescue analgesic 2.88 1.2 7.64 1.47.1 dose (hr) Table (6): Comparison of nausea and vomiting in both study groups. Postoprative nausea and vomiting: 1 2 6 9 1 37.5 56.2 6.2 22 Post-operative VAS Count % Count % 1... Fig. (1): VAS for two groups over time. <.1 Discussion Thoracic paravertebral block is a technique creating unilateral somatic and sympathetic nerve block as a result of local anesthetic solution injection in thoracic paravertebral space [4]. The ultrasound technology increases the ability to visualize the pleura and other structures in and around the paravertebral space and increase the interest in performing thoracic paravertebral block. Ultrasound technology has allowed us to broaden the depth of our knowledge of the anatomy of the paravertebral space in addition to enabling us to visualize the anatomic structures, the needle, and the spread of local anesthetic [3]. In our study, 48 female patients scheduled for elective breast surgery (biopsy, fibroadenoma resection, simple mastectomy). They were randomly divided into 2 groups each (n=24). In our study there was faild block in 1 cases and sucss block in 38 cases from total 48 patients. Sucss rate in was (66.7%) and (91.7%) in. Study done by Greengrass et al., compared the safety and efficacy of paravertebral block as a sole anesthetic technique for intraoperative and postoperative management of modified radical mastectomy with those of general anesthesia. Surgery was successfully completed in (85%) of the cases attempted by using paravertebral block alone, and in (91%) of cases the surgery was completed by using paravertebral block supplemented with local anesthetic infiltration [7]. Similarly to our study Cheema and colleagues reported that ultrasound guidance, seem to increase the safety and success of the technique compared with the blind (loss of resistance) technique [8]. In our study the means to assess post operative pain control was the time to first analgesic consumption and the VAS scores at different times (2, 6, 12h) of post operative period. The time to first analgesic in the postoperative period was significantly greater in (7.64) than in (2.88). Klein and colleagues, found reduced pain scores even at 24h post-operatively. Which may be due to they use ropivacine instead of bupivacine in our study. But we had the same conclusion that multiple injection technique improve the duration and quality of analgesia of TPVB [9].

Randa I. Badawy, et al. 239 Also in the study of Pusch and colleagues, 86 women were included, 44 patients received a singleinjection paravertebral block, while 42 patients were treated with general anaesthesia. Lower pain scores were found in the PVB group than the control group throughout the study [1]. Data represented in our study showed that the incidence of postoperative nausea and vomiting was higher in the (64%). This may be a result of increase the requirement of opioids among the this group. But the overall incidence of PONV of both groups about (26%). In a study done by Coopey and colleagues they found a significant improvement in the rates of antiemetic use postoperatively in patients who had a PVB, antiemetic used in 3 8.8% of PVB group and in 56.8% of control group who recivied general anathesia (p<.1) [11]. Arunakul and colleagues as well, found that the incidence of PONV is quite high in the patient undergoing modified radical mastectomy (64%). In their study, a PVB lowered the severity of PONV and antiemetic requirement (6.6%) [12]. Our study shows that there were no incidence of complications especially with the direct visualization of paravertebral space and real time injection of the local anesthetic under ultrasound guidance. Unlike our study, Pekka and colleagues reported one of the serious complications that a part of the solution might have been accidentally injected intravascularly [13]. Naja's study, where nerve stimulation technique was adopted, included inadvertent vascular puncture (6.8%), hypotension (4.%), hematoma (2.4%), pain at the site of skin puncture (1.3%), signs of epidural or intrathecal spread (1.%), pleural puncture (.8%), and pneumothorax (.5%) were encountered in this study. Such complications are rare, but serious [14]. To conclude, the use US-guided TPVB is feasible, effective, has a high success rate, and decrease the incidence of complications due to direct visualization of anatomical structures, the needle and spread of local anesthetic. References 1- KARMAKAR M.K. and HO A.M.: Thoracic and lumbar paravertebral block. In: Hadzic A. (editor). Textbook of regional anesthesia and acute pain management, 1 st ed. NewYork: McGraw-Hill; p. 583-97, 27. 2- BOEZAART A.: Paravertebral block: Cervical, thoracic, lumbar, and sacral. Current Opinion in Anaesthesiology, 22: 637-43, 29. 3- SHIBATA Y. and NISHIWAKI K.: Ultrasound-guided intercostal approach to thoracic paravertebral block. Anesth. Analg., 19: 996-7, 29. 4- BEN-ARI A.: Ultrasound guided paravertebral block using an intercostal approach. Anesth. Analg., 19: 1691-4, 29. 5- CHAN Y.H.: Biostatistics 12: Quantitative Data- Parametric and Non-parametric Tests. Singapore Med. J., 44 (8): 391-6, 23a. 6- CHAN Y.H.: Biostatistics 13: Qualitative Data-Tests of Independence. Singapore Med. J., 44 (1): 498-53, 23b. 7- GREENGRASS R., O'BRIEN F., LYERLY K., et al.: Paravertebral block for breast cancer surgery. Can. J. Anaesth., 43: 858-61, 1996. 8- CHEEMA S., RICHARDSON J., McGURGAN P., et al.: Factors affecting the spread of bupivacaine in the adult thoracic paravertebral space. Anaesthesia, 58: 684-711, 23. 9- KLEIN S.M., BERGH A., STEELE S.M., et al.: Thoracic paravertebral block for breast surgery. Anesth. Analg., 9: 142-5, 21. 1- PUSCH F., FREITAG H., WEINSTABL C., et al.: Singleinjection. Paravertebral block compared to general anaesthesia in breast surgery. Acta. Anaesthesiol. Scand., 43: 77-4, 1999. 11- COOPEY S.B., et al.: Use of preoperative paravertebral block decreases length of stay in patients undergoing mastectomy plus immediate reconstruction. Annals of Surgical Oncology, 2 (4): pp. 1282-6, 213. 12- ARUNAKUL P., RUKSA A., et al.: General anesthesia with thoracic paravertebral block for modified radical mastectomy. Journal of the Medical Association of Thailand, 93 Suppl 7. pp. S149-S153, 21. 13- PEKKA M. KAIRALUOMA, M.S.B, et al.: Single-injection paravertebral block before general anesthesia enhances analgesia after breast cancer surgery with and without associated lymph node biopsy. Anesthesia and analgesia, 99 (6): pp. 1837-43, 24. 14- NIIYAMA Y., KAWAMATA T., SHIMIZU H., et al.: The addition of epidural morphine to ropivacaine improves epidural analgesia after lower abdominal surgery. Can. J. Anaesth., 52: 181, 25.

24 Ultrasound Guided TPVB versus Blind Landmark Technique for Breast Surgery