Nghiên cứu tác dụng vô cảm trong mổ và giảm đau sau mổ của gây tê cạnh cột sống ngực kết hợp gây mê cho mổ ngực một bên ở trẻ em TT TIENG ANH

MINISTRY OF EDUCATION & TRAINING MINISTRY OF HEALTH HANOI MEDICAL UNIVERSITY THIEU TANG THANG EFFECTIVENESS OF THORACIC PARAVERTEBRAL BLOCK COMBINED WITH ANESTHESIA IN INTRAOPERATIVE ANESTHESIA AND POSTOPERATIVE ANALGESIA IN CHILDREN WITH UNILATERAL THORACIC SURGERY Speciality: Anesthesiology Code: 62720121 SUMMARY OF MEDICAL THESIS HA NOI - 2021 THIS WORK WAS COMPLETED AT HA NOI MEDICINE UNIVERSITY Supervisor: Assoc.Prof.Dr Cong Quyet Thang Reviewer 1: Reviewer 2: Reviewer 3: The thesis will be defended before the University Thesis Assessment Council At … , Date Month Year 2021 Thesis can be found at: - National Library - Library of Hanoi Medical University INTRODUCTION Thoracic surgeries are major surgeries that directly affects two critical system of the body - the respiratory system and circulatory system, with constant potential risks of serious complications during and after the operation Post operative pain is a common worry, even obsessive fear for the patient and mutually a top concern of anesthesiologists There are many methods of intraoperative anesthesia and postoperative analgesia, which can be used individually or in a combination In many centers, epidural block (EB) is considered the gold standard for pain management for thoracic surgeries However, this method is not suitable for all patients and may cause low blood pressure, neurologic injuries and urinary retention In recent years, ultrasoundguided (US) paravertebral block (PVB) is being accepted as an alternative to EB, gaining a considerable amount of attention from anesthesiologists Anaesthesia and resuscitation for thoracic surgery in children have always been a challenge for anesthesia practicians Postoperative analgesia for thoracic surgery is a mandatory requirement, especially in children Along with the development of ultrasound, interest of using specific technique to limite block on the desired site and desired side is steadily increasing The thoracic paravertebral block (TPVB) technique is more commonly used, especially in high-risk individuals such as children to limit the complication caused by the classic EB Around the world the number of researches on TPVB is increasing However, in Viet Nam, research on TPVB is still limited especially on children Coming from this reality, we conducted this study with the following two objectives: To compare the efficacy of analgesia between ultrasound-guided thoracic paravertebral block compared with epidural block by levobupivacaine 0.125% and fentanyl 2µg/ml during and after surgery in children with unilateral thoracic surgery To compare the effect of the two methods mentioned above on respiratory system, circulatory system and complications * New contributions of the thesis: The scientific and practical significance of the topic: - The research topic is necessary and pertinent, especially for application of ultrasound-guided paravertebral block, this topic has scientific and practical significance The research design is appropriate, scientific and logical; the data and the data processing is reliable, the number of patients is adequate - Postoperative analgesia for thoracic surgery is a mandatory requirement, especially for children There are many analgesia methods that can be used, and all of them have pros and cons to consider With the development of ultrasound, TPVB is becoming a technique of interest due to its analgesia effects and limiting some of the complications of the classic EB method In Vietnam, there is no research on this issue in children so it has scientific and practical value Evaluate the achieved results, new contributions of the thesis in the practice of anesthesia and resuscitation in children: The results of the thesis show that using US- PVB for unilateral thoracic surgery in children has good analgesia and has synery effect with general anesthesia during intraoperative period In terms, the majority of patients are in pain control with FPS-R 20ml/kg) during surgery The patient had to be transfered to mid-sternal surgery 2.2 Research Methods 2.2.1 Study design: The study is a randomized controlled clinical research 2.2.2 Sample size: Sample size: Use the formula to calculate the estimated sample size for a clinical study which is designed to be divided into groups: n 2C ES2 ES  μ  μ1 σ1 The result is n = 35, so in this study, we selected at least 40 patients in each group 2.2.3 Time – location of the study: From January 2017 to December 2019 at the Department of Anesthesia and Resuscitation, Vietnam National Children's Hospital 2.2.4 Means of research 2.2.5 Evaluation criteria in the study Objective 1: Analgesia during surgery: Pulse, blood pressure in surgery PRST anesthesia score in surgery for groups at the time of the study The mixture of levobupivacaine 0.125% + fentanyl anesthesia is used for anesthesia in surgery Fentanyl and other drugs used in surgery Time required for the first postoperative dose of analgesia Postoperative analgesia: - Location of analgesia distribution, level of pain reduction Onset time of analgesic effect - Comparing the resting FPS-R pain score and the percentage of analgesia rate according to the Oates classification at different time points of the study between the two groups - FPS-R pain score for cough and movement and the percentage of analgesia by Oates at different time points of the study between the two groups - Anesthetics mixture consumtion A comparison of the amount of anesthetic levobupivacaine used in the two groups for analgesia in day and day and total dose over the two days of analgesia - Number of patients and the amount of morphine used by the patient as rescue analgesia - Time when patient have adequate coughs, sits up, walks and remove catheter Objective 2: - Effects on respiration: Changes in breath rate, SpO2 at different time points of the study Analysis of the changes in arterial blood gas at different time points: Before one-lung ventilation 30 minutes after onelung ventilation After extubation The first day after surgery (24 hours after surgery) - Effects on circulation: changes in heart rate, blood pressure at different time points of the study, rate of patient with hypotension - Some other complications: Over sedation, nausea and vomiting, urinary retention, pruritus, respiratoyry failure, anesthetic toxicity, tremor Complications related to epidural catheter technique (epidural hematoma, epidural puncture, infection, puncture the pleural cavity) Other evaluation criteria: - Anthropometric characteristics of the patient - Anesthesia and surgery charecteristics: anesthesia duration, surgery duration, time of hospital stay after surgery, one-lung ventilation time, time to insert anesthetic catheter, time to wait for the effect of anesthetic, recovery time after surgery time performing the anesthesia technique, surgical methods 11 - Time of catheter withdrawal: after taking research data of 48 hours postoperative analgesia (H48) Analgesia after catheter withdrawal: after removing the catheter if the patient still has pain, continue intravenous injection with morphine 0.05mg/kg/time, maximum morphine dose 0.4 mg / kg / hours and paracetamol 15mg/kg/8 hours Time to monitor the patient: During surgical anesthesia: before induction of anesthesia; before analgesia; 15 minutes after analgesia; before skin incision; OLV (skin incision); OLV 15 minutes; OLV for 30 minutes; OLV 45 minutes; OLV 60 minutes; OLV 90 minutes; OLV 120 minutes; after skin closure; after extubation Convention on post-operative data collection times: Research time: H0, H1/4, H1/2, H1, H2, H4, H8, H12, H18, H24, H32, H40 and H48 2.2.7 Analysis and data processing Research data were analyzed and processed using to SPSS 16.0 software 2.2.8 Ethical issues in research 2.2.9 Research diagrams CHAPTER RESEARCH RESULTS 3.1 General characteristics of study patients 3.1.1 Characteristics of research subjects The average age of the TPVB group was 6.00 ± 3.27 years old, of the EB group was 7.13 ± 2.95 years old (p > 0.05) There was no difference in age, sex, height, weight between the two groups (p > 0.05) 3.1.2 Features about the surgery There was no difference in method of surgery, manner of surgery, and length of incisions (open surgery patients) between the two groups (p > 0.05) There was no difference in the dosage of drugs used in anesthesia, time of anesthesia, time of surgery and time of endotracheal extubation (p > 0.05) 3.1.3 Characteristics related to anesthesia technique There was no difference in needle injection position, depth of catheter inserted, and time to perform anesthesia technique between the two groups (p > 0.05) Rate of first attempt success and number of punctures: The rate of the first attempt success of the US-PVB was 85.0% higher than the EB method, accounting for 77.5% 12 The average number of sucesse injection attempt of the IC group was 1.15 ± 0.36 and the EB group was 1.23 ± 0.42, the difference between the two groups was not statistically significant, p > 0.05 3.2 Intraoperative analgesia effect of thoracic paravertebral block compared with epidural block 3.2.1 Dose of anesthetic mixture in surgery The average volume of anesthetic mixtures of the TPVB or EB group anesthetic was 7.7  3.9 ml and 8.7  3.2 ml The difference between the groups is not statistically significant (p > 0.05) The levobupivacaine 0.125% anesthetic injected with the initial dose for anesthesia in surgery of the two groups of anesthesia TPVB and epidural EB was 9.6  4.9 mg and 10.9  3.9 mg The difference between the groups is not statistically significant (p > 0.05) 3.2.2 Drugs used in surgery The average amount of intravenous fentanyl used during surgery between the two groups was not statistically significant, p > 0.05 The difference in the rate of patients using intravenous fentanyl supplemental analgesia during surgery in the TPVB group and the EB group is not statistically significant, p > 0.05 Pre-anesthesia drugs, hypnotics, muscle relaxants dose used in anesthesia of two different groups had no statistical meaning, p> 0.05 3.2.3 Evaluation of changes in heart rate and blood pressure during surgery Table 3.1 Characteristics of heart rate in surgery Group Time Baseline Before analgesia 15 minutes after anesthesia Before skin incision OLV (skin incision) OLV 15 minutes OLV 30 minutes OLV 45 minutes OLV 60 minutes OLV 90 minutes (n = 56) OLV 120 minutes (n = 26) After skin closure After extubation *** p < 0.001 TPVB n = 40 106.2 ± 12.5 105.6 ± 11.5 94.9 ± 9.5 *** 100.2 ± 9.0 *** 105.1 ± 9.4 105.9 ± 11.4 104.6 ± 11.2 106.4 ± 10.5 106.3 ± 10.3 104.5 ± 9.5 102.7 ± 10.3 103,3 ± 8,6 105.6 ± 10.2 EB p n = 40 104.4 ± 11.4 > 0.05 103.8 ± 11.2 > 0.05 96.7 ± 11.4 *** > 0.05 99.7 ± 11.6 *** > 0.05 104.6 ± 11.7 > 0.05 103.9 ± 12.1 > 0.05 102.7 ± 12.8 > 0.05 104.2 ± 14.3 > 0.05 103.7 ± 12.5 > 0.05 101.9 ± 11.5 > 0.05 103.5 ± 9.4 > 0.05 100,8 ± 8,5 > 0.05 103.8 ± 9.9 > 0.05 13 Table 3.2 Characteristics of mean blood pressure in surgery Group TPVB EB Average p (n = 40) (n = 40) blood pressure (mmHg) Baseline 71.2 ± 5.1 71.0 ± 4.9 > 0.05 Before analgesia 70.9 ± 6.9 70.7 ± 6.1 > 0.05 15 minutes after anesthesia 68.6 ± 6.2 ** 65.9 ± 5.7 *** 0.05 OLV (skin incision) 72.7 ± 6.9 70.5 ± 6.3 > 0.05 OLV 15 minutes 71.7 ± 6.1 70.3 ± 5.3 > 0.05 OLV 30 minutes 71.6 ± 5.7 70.2 ± 4.3 > 0.05 OLV 45 minutes 71.8 ± 6.1 70.2 ± 4.9 > 0.05 OLV 60 minutes 71.4 ± 5.9 70.0 ± 5.1 > 0.05 OLV 90 minutes (n = 56) 70.7 ± 5.3 70.1 ± 4.4 > 0.05 OLV 120 minutes (n = 26) 70.2 ± 5.5 69.2 ± 2.7 > 0.05 After skin closure 71,4 ± 5,6 69,6 ± 5,4 > 0.05 After extubation 71.2 ± 5.4 69.7 ± 5.2 > 0.05 * p < 0.05; ** p < 0.01; *** p < 0.001 After 15 minutes of anesthesia, heart rate, average blood pressure of both groups decreased compared to preanesthesia (p < 0.001) Mean blood pressure of the EB group decrease more than the TPVB group at some time with p > 0.05, and at 15 minutes after anesthesia with p < 0.05 3.2.4 Characteristics of sedation, respiratory, blood gas in surgery PRST scores of groups were similar, the difference was not statistically significant, p > 0.05 EtCO2 at all time points in surgery is higher than before surgery, EtCO2, SpO2 of the groups have no statistical meanings at all time points of the study, p > 0.05 The difference was not statistically significant between the groups in blood gas index after intubation, in surgery (p > 0.05) 3.3 Postoperative analgesic effect of TPVB analgesia 3.3.1 Onset of analgesic effect and spread of the anesthetic - The onset time of the analgesic effect (onset time) of the TPVB group was 9.4  1.4 minutes, the EB group was 9.3  1.6, the difference is not statistically significant, p > 0.05 - The average number of inhibited spinal nerves in the TPVB and EB groups was 6.6  0.9 and 6.8  0,9 respectively, the lowest is spinal nerves, the highest is spinal nerves 14 3.3.2 Dose of anesthetics mixtures used after surgery The total amount of anesthetic levobupivacaine used in the 24 hours, 24 hours after sugery and 48 hours after surgery of the TPVB group compared the EB group, respectively 112.7 ± 50.9 mg, 95.8 ± 43.9 mg, 207.2 ± 94.9 mg vs 120.6 ± 35.6 mg, 105.7 ± 30.8 mg, 228.4 ± 66.3 mg There is no statistically significant difference between the TPVB group and the EB group with p > 0.05 The total amount of fentanyl drug used with levobupivacaine anesthetic in the next 24 hours, 24 hours and 48 hours after surgery has no statistically significant difference between the TPVB group and the EB group with p > 0.05 3.3.3 Number of patients and amount of morphine used as rescuer The rate of patients with additional analgesia with intravenous morphine in the TPVB group (25%) and EB group (22.5%), p> 0.05 The total morphine dose used for additional analgesia in 48 hours after surgery of the TPVB and EB group was 3.76 2.24 mg and 3.79  1.69 mg, p > 0.05 3.3.4 Evaluation of postoperative pain severity Chart 3.1 Postoperative FPS-Rstatic pain score After analgesia, there is a statistically significant drop of FPS-Rstatic score compared to time H0 (p < 0.001) The mean FPS-Rstatic score of the TPVB group and the EB group had no statistically significant different, p > 0.05 15 Figure 3.2 FPS-Ractive pain points after surgery After performing analgesia, FPS-Ractive was statistically significantly lower than the time of H0, p < 0.001 3.3.5 Postoperative recovery time of the patient The time until patient can start sitting independently and walking independently after surgery of the ICU group compared with the EB group was 14.2 ± 5.4 hours and 21.9 ± 8.8 hours compared to 14.0 ± 5.9 hours and 20 , ± 7.6 hours, p > 0.05 3.4 Changes in circulation, respiration, and some complications 3.4.1 Changes in circulation at different time points after surgery Heart rate after injecting the mixture of anesthetics after 15 minutes onwards both decreased more than before the anesthesia (p < 0.05) Heart rate of the two groups was similar at all times of the study (p > 0.05) Table 3.3 Characteristics of mean blood pressure after surgery Mean blood pressure (mmHg) H0 H1/4 H1/2 H1 H2 H4 H8 H12 H18 H24 H32 H40 H48 Group * p < 0.05; *** p < 0.001 TPVB (n = 40) EB (n = 40) p 72.5 ± 8.2 71.8 ± 8.6 70.8 ± 7.6 70.8 ± 6.6 71.7 ± 8.9 71.2 ± 7.8 72.2 ± 8.0 72.3 ± 5.4 71.6 ± 6.8 71.9 ± 6.7 70.9 ± 7.5 72.3 ± 6.9 72.9 ± 5.9 71.5 ± 4.4 68.2 ± 3.6 *** 70.5 ± 4.7 70.3 ± 4.3 * 70.8 ± 3.6 69.6 ± 5.6 * 70.1 ± 4.1 * 70.4 ± 3.8 70.7 ± 5.2 71.2 ± 5.2 70.4 ± 4.2 70.7 ± 3.9 71.2 ± 4.4 > 0.05 < 0.05 > 0.05 > 0.05 > 0.05 > 0.05 > 0.05 > 0.05 > 0.05 > 0.05 > 0.05 > 0.05 > 0.05 16 In the EB group, the mean blood pressure decreased compared to different time points after analgesia, especially at 15th minutes, p < 0.001 At 15 minutes after the first dose of analgesia bolus, the mean blood pressure of the EB group was lower than the TPVB group, p 0.05 After receiving analgesia, the PSSS sedation scores of the two groups decreased significantly compared to the time of H0, p < 0.001 None of the patients had deepsedation during postoperative analgesia follow-up 3.4.3 Changes in arterial blood gas At the time of the study, the pH index, PCO2, PaO2 and HCO3- of the two groups did not differ, p > 0.05 3.4.4 Some complications Table 3.4 Some other complications Group TBVP EB (n=40) (n=40) p n % n % Complications Nausea, vomiting 7,5 12,5 > 0,05 Itching 10 15,0 > 0,05 Tremor 12,5 15,0 > 0,05 Urinary retention 7,5 15,0 > 0,05 Respiratory depression 2,5 5,0 > 0,05 Arrhythmia 0,0 2,5 > 0,05 Hypotension 5,0 15,0 > 0,05 Postsurgery Headache 0,0 5,0 > 0,05 Accidental vessel puncture 2,5 5,0 > 0,05 CHAPTER DISCUSSION 4.1 General characteristics of patients in the study 4.1.1 Characteristics of study patients Our study found there was no statistically significant differences in age, height and weight between the two groups, p > 0.05 Table 3.2 shows that the percentage of male patients is higher than female patients (55.0% compared to 45.0%) Our sex ratio is similar to the research by Chalam S, on using PVB to reduce postoperative pain from pediatric 17 patent ductus arteriosus surgery, which is 54% and 46% respectively The gender distribution ratio between the two different groups are not statistically significant with p > 0.05 4.1.2 Characteristics of the surgery performed Classification of surgery In our study, 55.0% of the patients in TPVB group received endoscopic thoracic surgery group compared with 57.5% of the EB group, 45.0% of the patients in TPVB group received open surgery compared with 42.5% of the EB group, p > 0.05 Therefore, the two group has same level of surgery extension The research patients mainly had lobectomy (48.8%), followed by mediastinal tumor resection (42.5%), diaphragm reconstruction surgery (8.8%) The difference in surgery type between the two groups has no statistically significant, p > 0.05 In our study, there were 35 patients had open surgery, the average length of the incision of TPVB group (18 patients) was 11.8 ± 1.7cm, and the EB group (17 patients) was 11.2 ± 1.0cm, p > 0.05 In our study, there were 34 patients undergone surgery for mediastinal tumors, including 16 patients in the TPVB group and 18 patients in the EB group These patients was operated on the left or right side, none had midsternal surgery, the patients who had large mediastinal tumors with incomplete unilateral analgesia was supplemented with fentanyl for intraoperative analgesia or morphine for postoperative analgesia according to study design The two groups also had no difference in the duration of anesthesia, duration of surgery and duration of endotracheal extubation, p > 0.05 4.1.3 Characteristics of PVB and EB technique Location of PVB and EB In our study, analgesia position accounted mostly at T6-T7 in both group In paravertebral block group, T6 – T7 accounted for the highest rate at 87.5%, followed by T7 – ​ ​ T8 with 10.0% and at T5 – T6 with 2.5% The locations of epidural block at T6 – T7, T7 – ​ ​ T8, T5 – T6 are 80.0%, 5.0% and 2.5%, respectively The analgesia distribution of the two groups was not statistically significant with p> 0.05 Location of TPVB or epidural thoracic anesthesia depends on the surgical site, the properties of the spine on each patient In the study of German NT anesthesia for surgery to treat lung cancer, the patient performed at the T6 – T7 vertebrae was the highest, accounting for 65.22%, the slit T5 – T6 accounted for 30.44% and the slot T7 – T8 accounts for 4.34% The mean depth of the thoracic paravertebral space (from the skin to 18 the thoracic paravertebral space) was 2.7 ± 0.56 cm (2 – cm), and the epidural space was 2.55 ± 0.51 cm (2-3 cm) The catheter depth of the two groups was not statistically significant with p > 0.05 (table 3.10) Our results are similar to the study of author Wong J (2019) studying the distance from the skin to the epidural space on 645 children in Southeast Asia aged to 19 years old Distribution of time to perform the analgesia technique The average time of analgesia catheter: from the time of Tuohy needle insertion to the completion of the fixation of the epidural or paravertebral catheter is 10.9 ± minutes and 11.7 ± 2.1 minutes, respectively Mean analgesia time of the EB group (18.0 ± 2.8 minutes) was shorter than that of the paravertebral group (19.1 ± 3.1 minutes) with p > 0.05 The average time to perform of the two groups was 18.6 ± 3.0 minutes Time to perform TPVB varies widely depending on the definition and experience of the operator 4.2 Intraoperative analgesia effect of thoracic paravertebral block compared with epidural block 4.2.1 Mixed dose of anesthetic for anesthesia in surgery The mixture of levobupivacaine 0.125% and fentanyl 2µg / ml used for anesthesia in surgery of the two groups was 7.7. 3.9 ml and 8.7  3.2 ml (p > 0.05) The levobupivacaine 0.125% used for anesthesia in the surgery of the two groups TPVB and EB are 9.6. 4.9 mg and 10.9 3.9 mg There was no statistically significant difference between the groups (p > 0.05) 4.2.2 The level of drug consumption used in anesthesia The dose of fentanyl in anesthesia: Fentanyl used in anesthesia for surgery in the two groups of TPVB and epidural patients is (102.5 ± 52.2 μg and 116.7 ± 40.0 μg), with p> 0.05 Author Vogt A TPVB in video-assisted thoracoscopic surgery, injecting dose of 0.4 ml/kg bupivacaine 0.375% with adrenaline before skin incision The amount of fentanyl used in surgery of the TPVB group was lower than the group without analgesic (2.3 ± 1.3 μg/kg compared with 3.3 ± 1.2 μg/kg of fentanyl, p < 0, 05) Proportion of patients need additional intravenous fentanyl during surgery: The rate of patients need additional fentanyl in surgery of TPVB group was similar to the EB group (32.5% and 30.0% respectively), with p > 0,05 Preanesthetic agent, hypnotics, muscle relaxants for anesthesia: Table 3.15 shows that the different of midazolam, propofol and atracurium dose for anesthesia between groups are not statistically significant, p > 0.05 19 4.2.3 Changes in heart rate, blood pressure in surgery Avarage heart rate after preanesthesia (baseline) of the two groups PVB and EB were similar (106.2 ± 12.5 compare to 104.4 ± 11.4) with p > 0,05 After 15 minutes of anesthesia, the heart rate of both groups decreased compared to the baseline heart rate, the TPVB group was (94.9 ± 9.5 versus 106.2 ± 12.5) with p < 0.001, the EB group was (96.7 ± 11.4 compared to 104.4 ± 11.4) with p < 0.001; The difference between the two groups after providing analgesia not statistically significant (94.9 ± 9.5 versus 96.7 ± 11.4) with p > 0.05 (table 3.1) Mean blood pressure after the preanesthesia (baseline) of the two groups TPVB and EB are similar (71.2 ± 5.1 compared to 71.0 ± 4.9 mmHg) with p > 0.05 However, after 15 minutes of anesthesia, mean blood pressure decreased compare to baseline in both groups p < 0.01; in the TPVB group is 68.6 ± 6.2 compare to 71.2 ± 5.1 mmHg; In the EB group is 65.9 ± 5.7 compare to 71.0 ± 4.9 mmHg; Mean blood pressure of the EB group is lower than the TPVB group (65.9 ± 5.7 compared to 68.6 ± 6.2 mmHg) with p < 0.05 (table 3.2) The study of Casati A comparing EB and TPVB in lung surgery showed that 19% of patients in the EB group had their blood pressure decreased ≥ 30% compared to baseline blood pressure, while no patients in TPVB group had decreased ≥ 30% Mean blood pressure of the TPVB group fluctuate less than of EB group, this is the difference compare to EB, because TPVB only blocks one of the parasympathetic sides, maintaining stable mean blood pressure level and less drop in blood pressure compared to EB Other follow-up time points during surgery found no difference between the groups with p > 0.05 (tables 3.1 and 3.2) Thus, the heart rate and blood pressure in surgery of both groups are stable during surgery, this proves the anesthetic effect during surgery of TPVB and EB 4.2.4 Time of endotracheal extubationand and the time required for the first dose of analgesia after surgery Time of endotracheal extubationand of the TPVB group was shorter than that of the EB group, but the different has no statistically significance, p> 0.05 (57.4 ± 71.1 minutes compared with 67.4 ± 81.8 minutes) The results show that the time to first analgesia dose requirement of the two groups of TPVB and EB are respectively 46.2 ± 5.8 and 44.3 ± 6.4 minutes, the difference was not statistically significant with p > 0.05 According to the author NH Thuy TPVB with dose injected before surgery has analgesic effect after surgery, prolonging the painless time after surgery for patients 4.3 Discuss on postoperative analgesic effect of PVB and EB 20 4.3.1 Onset time of analgesic effect The onset time of analgesic effects varies depending on the anesthetic technique, concentration and volume of anesthetic used The onset time in our study was similar to the results of T.Đ.Tho, the average time of onset of analgesic effect was 9.03 ± 1.93 minutes.Mendola (2009) studied 150 postoperative patients with continuous infusion of epidural different concentrations of levobupivacaine 0.5%, 0.25% and 0.15% in combination with sufentanyl 2.6 μg / hour with At the rate of 10 mg / hour, the author also found that the higher the concentration was, the shorter the onset time In the study of TT Trung, the onset of analgesic effect was 11.9 ± 6.0 minutes in the TPVB group and 11.6 ± 6.5 minutes in the EB group 4.3.2 Drugs used for pain management Analgesic selection and combination: In this study, we selected levobupivacaine with fentanyl for intraoperative anesthesia and postoperative analgesia because of their advantages, fentanyl is a lipid soluble morphine drug, when pumped into the paravertebral space or epidural space, the drug distribute alot into the blood vessels, low absorption through the meninges Authors around the world with many clinical reports on the use of fentanyl in regional anesthesia, they conclude about the advantages of fentanyl over morphine for analgesia stronger pain reliever during resting or excercising, reduce respiratory distress complications by 50 times, reduce complications (vomiting, nausea, itching, drowsy, urinary retention) Concentration and dosage of the anesthetic mixture:The choice of the optimal concentration of anesthetic and the combination drugs in TPVB or EB is based on the balance between analgesic efficacy and complications For levobupivacaine, the recommended concentration for analgesia is from 0.0625% to 0.2% in according to different studies The concentration of levobupivacaine anesthetic we used in the study was 0.125%, this is the most commonly used concentration in analgesic application studies by authors around the world, combining with fentanyl 2μg / ml With this concentration, the authors showed that the main effects are analgesia, less motor inhibition and lower blood pressure 4.3.3 The levobupivacaine we used in this study We also did not see any difference in the total dose of morphine used between the two groups (p > 0.05) That proves that, patients in the two groups have good pain management and the pain management effect in the two groups is the same Our results are consistent with some other studies such as T.T.Trung (2019) concluded that the proportion of patients requiring additional intravenous morphine 21 analgesia in the TPVB group was 19.6%, in the EB group was 13.7% (p > 0.05) 4.3.4 Compare the analgesic effects of the two groups after surgery Comparison of resting analgesia effects of groups (FPS-Rp) The results in chart 3.1 show the average FPS-R score at rest at H0 of the US-PVB is 5.35 ± 0.95 and in the EB group is 5.10 ± 1.01, the difference between the two groups is not statistically significant with p > 0.05 Immediately 15 minutes after the anesthetics injection (H1/4) FPSRstatic scores in both groups decreased rapidly compared with the time before the anesthetic injection (H0) is statistically significant with p (H1/4 - H0) < 0.001: TPVB group (2.85 ± 1.01) and EB group (2.75 ± 0.98), however, there was no statistically significant difference between the two groups with p > 0.05 Average FPS-Rstatic scores at time of rest of the two groups at the monitoring times were statistically significantly lower than that at the time of H0 (p < 0.001) Our results were similar to T.T Trung at the time of initiation of analgesic injection (Ho), the average visual analog scale while resting (VASstatic) of the TPVB group was 6.9 ± 1.4 points and that of the EB group is 6.5 ± 1.2 points At H1/4, the VASstatic score was 3.5 ± 1.0 and 3.5 ± 0.9 points After 30 minutes of anesthetic injection (H1/2) and other study time points in 48 hours after surgery, both groups achieved an average FPSRstatic score of less than points, but there was no difference between the two groups with p > 0.05 The FPS-Rstatic score at H1, H24, H48 of the two groups is 1.95 ± 0.55 compared to 1.80 ± 0.88; 1.65 ± 0.77 compared to 1.88 ± 0.85; 1.85 ± 0.53 compared to 1.75 ± 0.67 points Thus, after 30 minutes of anesthetic injection (H1/2) and other study times in 48 hours after surgery, the patient does not feel pain when in a stationary state Akinci (2019) performed thoracic paravertebral blockunder ultrasound guidance on 40 children aged to years for nephrectomy, the FLACC pain scale was always less than at the study time points, good pain management after surgery Narasimhan P (2019) studied on 50 children from years old to 10 years old to compare the postoperative analgesia of thoracic paravertebral block compared with low-area epidural block in renal surgery Pain relief of thoracic paravertebral block group had lower FLACC pain score than epidural block group (p < 0.005) Compare the analgesia effects when cough or exercise between the two groups: According to the chart 3.2 on the FPS-R scale when exercising of the groups in the first 48 hours, we found that after 15 minutes of taking the drug (H1/4), the FPS-Ractive scores of the two groups both decreased more than at the time of H0, the TPVB group decreased from 22 5.45 ± 0.91 (H0 time) to 2.65 ± 0.95 (H1/4 time), the EB group decreased from 5.25 ± 0.98 (H0) to 2.70 ± 0.97 (H1/4), the difference is statistically significant with p < 0.001 However, between the groups, the difference is not statistically significant (p > 0.05) In our study, the FPS-R scores when cough and excersie of the groups were always 0.05) In this way, our study as well as studies of other authors show good analgesic effect when combining opioid with levobupivacaine in TPVB for pain surgery such as thoracic surgery Both TPVB and EB groups have analgesic effects through a good FPS-R during rest and coughing or exercise 4.3.5 Postoperative recovery The time until the patient can idenpendently sat up after surgery in the TPVB group was 14.2 ± 5.4 hour and EB group is 14.0 ± 5.9 hour (p > 0.05) The time until the TPVB group was able to walk is 21.9 ± 8.8 hours, of the EB group is 20.3 ± 7.6 hours, p > 0.05 Thus, postoperative recovery time is related to postoperative analgesia According to our analgesia results (graphs 3.1 and 3.2), patients showed good and good analgesia results in 30 minutes or more after injection 4.4 Effects on circulation, respiration and some complications 4.4.1 Change in circulation, respiration at the postoperative time The results of our study show that TPVB has more stability in blood pressure than EB, this is also consistent with the studies of Cucu (2005) and Aly (2010) Mean blood pressure of the TPVB group less fluctuated than the EB group, this is the difference compared to EB, because TPVB only blocks the parasympathetic side, thus maintaining a stable mean blood pressure and less drop in blood pressure compared with EB The changes in the saturation of peripheral oxgygen (SpO2) and Endtidal CO2 (EtCO2) of our research are always within the allowable limits There is no statistically significant difference between the two groups At the time of the study, the pH index, PaCO2, PaO2 and HCO3- of the two groups did not differ (p> 0.05) Our results are consistent with Aly (2010), the author also comments that pH, PaO2, PaCO2 of the TPVB and EB groups are similar at times 4.4.2 Some complications The rate of complications related to morphine drug of the TPVB group was lower than that of the EB group, but there was no statistically significant difference (p> 0.05) The results in Table 3.4 showed that the 23 rate of nausea - vomiting in general in 48 hours after surgery for the TPVB group was 7.5%, the EB group was 12.5% Author Berta E providing TPVB for kidney surgery in children under years old encountered nausea and vomiting rate is 16.7% El-Hamid had complications in the TPVB group such as nausea: 16%; vomiting 0%; urinary retention: 0%; pruritus: 6.6% while in the EB group, the prevalence is 30%; ten%; 16.6% and 16.6% The rate of hypotension in our study (5.0% in the TPVB group, 15.0% in the EB group) was similar to that of El-Hamid (3.3% in the TPVB compared with 20% in the EB group) El-Morsy GZ (2012) studied on 60 children and showed that the rate of vomiting, urinary retention, and hypotension in the EB group (14.8%; 11.1% and 14.8%) was higher than that of the TPVB group (0%; 0% and 3.6%) and the differences are statistically significant Complications related to the TPVB include vascular puncture: 2.5%, needle puncture pain: 0% Rate of these complications are lower than those of the EB group (5.0% and 5.0%) Our result is similar to research by author Kasanavesi (2015) studying the use of EB on 70 children, in which there are patients (2.85%) touching blood vessels under anesthesia, there is no case of epidural hematoma or poisoning with anesthetics The rate of successful anesthesia at the first puncture of the US-PVB was higher than that of the EB group, with p> 0.05 (85.0% and 77.5%) and the number of needle punctures of the group US-PVB was lower than the EB group, with p> 0.05 CONCLUSION Intraoperative and postoperative analgesia effect of thoracic paravertebral block compared with epidural block Thoracic paravertebral block under ultrasound guidance has the analgesic effect on pain management during surgery is equivalent to that of epidural block in unilateral thoracic surgery in children, showing: Heart rate and mean blood pressure from the time of skin incision were stable and the difference was not statistically significant between the groups The dose of drugs used in anesthesia of the TPVB group and the EB group was not statistically significant (with p > 0.05): fentanyl (102,5 ± 52,2 μg versus 116,7 ± 40,0 μg); propofol (69,25 ± 31,82 mg versus 74,0 ± 23,94 mg); atracurium (17,18 ± 12,26 mg versus 20,63 ± 10,71 mg) Thoracic paravertebral block under ultrasound guidance has a good effect on pain management after surgery, the analgesic effect is equivalent to that of epidural block in unilateral thoracic surgery in children, showing: FPS-R score at rest as well as when active at all study time points after performing postoperative analgesia < (p > 0.05), total dose of anesthetic mixture (levobupivacaine + fentanyl) used in 48 hours 24 postoperatively of the two groups was not statistically significant The proportion of patients using additional morphine and the total dose of morphine used in the TPVB group and the EB group were not statistically significant with p > 0.05: 25,0% and 3,76 ± 2,24 mg versus 22,5% 3,79 ± 1,29 mg, respectively Changes in circulation, respiration and some complications Thoracic paravertebral block has less effect on circulation than epidural block (intraoperative and postoperative): mean blood pressure at 15 minutes after bolus of analgestic of the EB group is statistically significant lower than the TPVB group with p < ,01: intraoperative (65.9 ± 5.7 mmHg versus 68.6 ± 6.2 mmHg) and postoperative (68.2 ± 3.6 mmHg versus 71.8 ± 8.6 mmHg) The proportion of patients with hypotension in the TPVB group was lower than in the EB group (5% versus 15%) There was no difference between the TPVB group and the EB group in terms of respiratory - The rates of nausea and vomiting, itching, shivering and urinary retention of the anesthesia group in 48 hours of study were 7.5%, 10.0%, 12.5% ​ ​ and 7.5% respectively, which are lower than those of EB group (12.5%, 15.0%, 15.0% and 15.0%), p> 0.05 - There were no dangerous complications such as: anaesthetic toxicity, total spinal anesthesia, pneumothorax, epidural hematoma or catheter-associated infection RECOMMENDATION Ultrasound-guided Paravertebral Block can be applied for unilateral thoracic surgery in children with a mixture of levobupivacaine 0.125% and fentanyl μg/ml Research on efficacy and safety of Ultrasound-guided Paravertebral Block should be conducted with larger sample sizes and in children under years old PUBLISHED SCIENTIFIC RESEARCH RELATED TO THE THESIS Thieu Tang Thang, Cong Quyet Thang (2019) The analgesic effect of epidural anesthesia in thoracic surgery in children Journal of practical medicine.No 11(1118), 48-50 Thieu Tang Thang, Cong Quyet Thang (2020) Effects of intraoperative anesthesia and postoperative analgesia of ultrasoundguided paravertebral block in children with unilateral thoracic surgery Viet Nam Medical Journal, No and 2, 487 55-59 Thieu Tang Thang, Cong Quyet Thang (2019) Ultrasound-guided paravertebral block for analgesia during and after surgery in children with unilateral thoracic surgery Journal of practical medicine No 1121 68-71 ... toxicity in children and management Management of local anesthetic systemic toxicity (LAST) in children: Lipid 20% is the firstline, main and most important drug used in the emergency of anesthetic... anesthesia technique between the two groups (p > 0.05) Rate of first attempt success and number of punctures: The rate of the first attempt success of the US-PVB was 85.0% higher than the EB method,... surgeries are major surgeries that directly affects two critical system of the body - the respiratory system and circulatory system, with constant potential risks of serious complications during