Surgical vs ultrasound-guided lumbar erector spinae plane block for pain management following lumbar spinal fusion surgery.

PURPOSE: Spinal surgery is associated with severe diffuse pain in the postoperative period. Effective pain management plays an essential role in reducing morbidity and mortality. This study is designed to compare the ultrasound-guided erector spinae plane (ESP) block and surgical infiltrative ESP block for postoperative analgesia management after lumbar spinal fusion surgery. METHODS: The patients who underwent two or three levels of posterior lumbar spinal fusion surgery were randomly allocated into one of three groups with 30 patients each (Group SE = Surgical ESP block; Group UE = ultrasound-guided ESP block; Group C = Controls). The primary aim was to compare postoperative opioid consumption, and the secondary aim was to evaluate postoperative dynamic and static pain scores and the incidence of opioid-related adverse effects. RESULTS: There was a significant difference in terms of opioid consumption, rescue analgesia on demand, and both static and dynamic pain scores between groups at all time periods (p < 0.05). Group SE and Group UE had lower pain scores and consumed fewer opioids than the controls (p < 0.05). However, the Group UE had lower pain scores and opioid consumption than the Group SE. The sedation level of patients was significantly higher in the control group than in the other two groups. Also, nausea was more common in controls than in the other groups. CONCLUSION: While both surgical and ultrasound-guided ESP blocks reduced opioid consumption compared to the controls, the patients who received ultrasound-guided ESP blocks experienced better postsurgical pain relief than those in the other groups (surgical ESP and controls).

The efficacy of rhomboid intercostal block for pain management after video-assisted thoracoscopic surgery: a prospective, randomized-controlled trial.

OBJECTIVE: We aimed to evaluate the efficacy of rhomboid intercostal block (RIB) for analgesia management in patients who underwent video-assisted thoracoscopic surgery. METHODS: Adult patients who underwent VATS under general anesthesia between July 2020 and June 2022 were included in the study. There was two groups in this study: RIB (n = 25) vs control (n = 25) group. RIB was performed with 30 ml 0.25% bupivacaine at the end of the surgery. Surgical intercostal blockade was performed with 30 ml 0.25% bupivacaine in the control group. The patients received intravenous fentanyl patient-controlled postoperative analgesia. The numerical rating score (NRS), opioid consumption, and adverse events were recorded. RESULTS: A total of 50 patients were randomized into 2 groups. There were no significant difference in terms of the demographic data between groups (P > 0.05). Postoperative opioid consumption at 0-8, 8-16, 16-24, and 24-48 h and rescue analgesic use were significantly lower in RIB group (P < 0.05). At all times, the static/dynamic NRS were significantly lower in RIB group. The rate of nausea and itching was higher in control group (P < 0.05). CONCLUSION: US-guided RIB provides effective post-VATS analgesia.

Lumbar erector spinae plane block versus infrainguinal fascia iliaca compartment block for pain management after total hip arthroplasty: a randomized clinical trial.

OBJECTIVE: We aimed to evaluate the effectiveness of ultrasound-guided facia iliaca compartment (FIC) and erector spinae plane (ESP) blocks in managing postoperative pain after total hip arthroplasty surgery. METHODS: A total of 60 patients were randomized into 2 groups (n = 30): one that received FIC blocks and one that received ESP blocks. FIC and ESP blocks were performed with 30 mL 0.25% bupivacaine at the end of the surgery. The patients received intravenous tramadol and patient-controlled postoperative analgesia. The pain scores, opioid consumption, and adverse events were recorded. RESULTS: The dynamic pain scores on movement in the postoperative first hour were significantly lower in the ESP block group than in the FIC block group (3 [2-4] vs 4 [2-5], respectively; P = .035). Data are expressed as median (25th-75th percentiles). Postoperative opioid consumption within the first postoperative 8 hours was significantly higher in the FIC block group than in the ESP block group (80 mg [61-100] vs 100 mg [80-120], respectively; P = .010). The adverse effects of opioids did not differ between the 2 groups. CONCLUSION: ESP and infrainguinal FIC blocks provided similar postoperative analgesia 24 hours after total hip arthroplasty. The ESP block is more beneficial than the FIC block in terms of pain scores and opioid consumption in the early hours of the postoperative period. TRIAL REGISTRATION: www.ClinicalTrials.gov (ID: NCT05621161).

YouTube Educational Videos for Peripheral Block Learning and Application: A Survey of Turkish Anesthesiologists; How Successful.

OBJECTIVE: The aims of this survey study were to evaluate the contribution of YouTube to nerve-block learning/education and the advantages and disadvantages of the YouTube. MATERIALS AND METHODS: A total of 24 questions were selected for the survey by consensus of the authors. Information in the form of web data was obtained through an electronic data form that was distributed via WhatsApp to known email addresses and phone numbers of 300 practitioners (anesthesia residents, anesthesiologists, and academicians). There were a total of 24 questions on the survey. The first section included 5 questions collecting demographic data, and the second part encompassed 19 questions about the YouTube nerve block videos. RESULTS: Among the participants, 232 of practitioners (86.9%) performed peripheral nerve blocks, and only 35 practitioners (13.1%) had no experience of nerve blocks so and used YouTube videos for educational purposes. According to our results, YouTube videos frequently improved performance. In addition, YouTube improved the training of practitioners in terms of the type of block procedure, identifying anatomical landmarks, target structures like nerves and blood vessels, needle visualization, needle depth, and patient position. CONCLUSION: YouTube contributes to the performance of regional anesthesia and to learning at all academic levels. It should not be forgotten that such videos are not peer reviewed by professionals in the relevant field.

Assessment of oxygen extraction rate changes following red blood cell transfusion in the intensive care unit: a protocol for a prospective observational non-interventional study.

INTRODUCTION: Haemoglobin transfusion thresholds have been used in the intensive care unit (ICU) to guide red blood cell transfusion (RBCT) decisions. Recent research has also focused on physiological indicators of tissue oxygenation as trigger points for blood transfusion. This study aims to assess the oxygen extraction rate (O2ER) as a critical indicator of the oxygen delivery-consumption balance in tissues and investigate its potential as a reliable trigger for blood transfusion in ICU patients by analysing clinical outcomes. The utilisation of physiological indicators may expedite the decision-making process for RBCT in patients requiring immediate intervention, while simultaneously minimising the risks associated with unnecessary transfusions. METHODS AND ANALYSIS: This prospective, single-centre, observational cohort study will include 65 ICU patients undergoing RBCT. We will evaluate essential markers such as arterial oxygen content, central venous oxygen content, arteriovenous oxygen difference, O2ER and near-infrared spectroscopy before and 15 min after transfusion. The primary outcome is the percentage increase in O2ER between the two groups relative to the initial O2ER level. Secondary outcomes will assess complications and patient outcomes in relation to baseline O2ER. A 90-day comprehensive follow-up period will be implemented for all enrolled patients. ETHICS AND DISSEMINATION: This study has obtained ethics committee approval from the Izmir Katip Celebi University Non-Interventional Clinical Studies Institutional Review Board. Written informed consent will be obtained from all patients before their enrolment in the study. The findings will be disseminated through publication in peer-reviewed journals and presentation at national or international conferences. TRIAL REGISTRATION NUMBER: NCT05798130.

Efficacy of modified thoracoabdominal nerve block through perichondrial approach following laparoscopic inguinal hernia repair surgery: a randomized controlled trial.

BACKGROUND: Modified thoracoabdominal nerve block through perichondrial approach is a novel fascial plane block and provides abdominal analgesia by blocking thoracoabdominal nerves. Our primary aim was to evaluate the efficacy of M-TAPA on quality of recovery and pain scores in patients who underwent laparoscopic inguinal hernia repair surgery (Trans Abdominal Pre-Peritoneal approach ‒ TAPP). METHODS: Patients with American Society of Anesthesiologists (ASA) physical status I-II aged between 18 and 65 years scheduled for elective TAPP under general anesthesia were enrolled in the study. After intubation, the patients were randomized into two groups: M: M-TAPA group (n = 30) and the control group (n = 30). M-TAPA was performed with total 40 ml 0.25% bupivacaine in the M group. Surgical infiltration was performed in the control group. The primary outcome of the study was the global quality of recovery score, the secondary outcomes were pain scores, rescue analgesic demands, and adverse effects during the 24-h postoperative period. RESULTS: The global quality of recovery scores at 24 h were significantly higher in the M group (p < 0.001). There was a reduction in the median static and dynamic NRS for the first postoperative 8 h in the M group compared to the control group (p < 0.001). The need for rescue analgesia was significantly lower in the M group compared to the control group (13 patients vs. 24 respectively, p < 0.001). The incidence of side effects was significantly higher in the control group (p < 0.001). CONCLUSION: In our study, M-TAPA increased patient recovery scores, and provided pain relief in patients who underwent TAPP. REGISTER NUMBER: NCT05199922.

Modified thoracoabdominal nerve block through perichondrial approach (M-TAPA) vs local infiltration for pain management after laparoscopic cholecystectomy surgery: a randomized study.

PURPOSE: Modified thoracoabdominal nerves block through perichondrial approach (M-TAPA) targets thoracoabdominal nerves. Our primary aim was to compare M-TAPA vs local infiltration on pain management in patients underwent laparoscopic cholecystectomy (LC) surgery. METHODS: Patients with ASA class I-II patients aged between 18 and 65 years scheduled for elective LC under general anesthesia were enrolled in the study. There were two randomized groups: Group M: M-TAPA group (n = 30) and the local infiltration (LI) group (n = 30). M-TAPA was performed with totally 40 ml 0.25% bupivacaine in the M group. LI was performed in infiltration group. The primary outcome of the study was pain score in the PACU, the secondary outcomes were the patient satisfaction scores, rescue analgesic need, and adverse effects during the 24-h postoperative period. RESULTS: The static NRS scores were significantly lower in Group M at the postoperative first 4 h (p = 0.001). There was a significant decrease in the dynamic NRS scores in Group M at the postoperative first 16 h (p = 0.001). The incidence of nausea was significantly higher in the LI group (12 vs. 5 patients, p = 0.047). The need for rescue analgesia was significantly lower in Group M (p = 0.009). The patient satisfaction scores were significantly higher in Group M (p = 0.001). CONCLUSION: M-TAPA provides superior analgesia compared to LI in patients undergoing LC.

Efficacy of modified thoracoabdominal nerve block through perichondrial approach following laparoscopic inguinal hernia repair surgery: a randomized controlled trial

Abstract Background: Modified thoracoabdominal nerve block through perichondrial approach is a novel fascial plane block and provides abdominal analgesia by blocking thoracoabdominal nerves. Our primary aim was to evaluate the efficacy of M-TAPA on quality of recovery and pain scores in patients who underwent laparoscopic inguinal hernia repair surgery (Trans Abdominal Pre-Peritoneal approach ‒ TAPP). Methods: Patients with American Society of Anesthesiologists (ASA) physical status I-II aged between 18 and 65 years scheduled for elective TAPP under general anesthesia were enrolled in the study. After intubation, the patients were randomized into two groups: M: M-TAPA group (n = 30) and the control group (n = 30). M-TAPA was performed with total 40 ml 0.25% bupivacaine in the M group. Surgical infiltration was performed in the control group. The primary outcome of the study was the global quality of recovery score, the secondary outcomes were pain scores, rescue analgesic demands, and adverse effects during the 24-h postoperative period. Results: The global quality of recovery scores at 24 h were significantly higher in the M group (p < 0.001). There was a reduction in the median static and dynamic NRS for the first postoperative 8 h in the M group compared to the control group (p < 0.001). The need for rescue analgesia was significantly lower in the M group compared to the control group (13 patients vs. 24 respectively, p < 0.001). The incidence of side effects was significantly higher in the control group (p < 0.001). Conclusion: In our study, M-TAPA increased patient recovery scores, and provided pain relief in patients who underwent TAPP. Register Number: NCT05199922.

The efficacy of ultrasound-guided anterior quadratus lumborum block for pain management following lumbar spinal surgery: a randomized controlled trial.

BACKGROUND: Quadratus lumborum block (QLB) is a fascial plane block. There is no randomized study on the efficacy of QLB for lumbar surgery. We evaluated the efficacy of QLB for postoperative pain management and patient satisfaction after lumbar disc herniation surgery (LDHS). METHODS: Sixty patients with ASA score I-II planned for LDHS under general anesthesia were included. We allocated the patients into two groups: the QLB group (n = 30) or the control group (n = 30). QLB was performed with 30 ml 0.25% bupivacaine in the QLB group. Paracetamol 1 g IV 3 × 1 was ordered to the patients at the postoperative period. If the NRS score was ≥ 4, 1 mg/ kg tramadol IV was administered as rescue analgesia. RESULTS: There was a reduction in the median static NRS at 0 h and 2 h with QLB compared to the control group (p < 0.05). There was no difference in the resting NRS at any other time point up to 24 h. The median dynamic NRS was significantly lower at 0, 2, 4, 8, and 16 h in the QLB group (p < 0.05). The need for rescue analgesia was significantly lower in the QLB group. The incidence of nausea was significantly higher in the control group. The postoperative patient satisfaction was significantly higher in the QLB group (p < 0.05). CONCLUSION: We found that the QLB is effective for pain control following LDHS.

The attitudes of Turkish physicians in the treatment of fibromyalgia; is 'Pregabalinophobia' the new reality of pain medicine?

OBJECTIVES: This study aims to determine the treatment preferences of physicians interested in fibromyalgia treatment and to investigate their hesitations about prescribing pregabalin. METHODS: Our survey study was conducted between February 5 and 20, 2021. The survey forms were sent to the known email addresses and phone numbers of 1569 physical medicine and rehabilitation (PMR), algology, and rheumatology physicians. The replies to the surveys were checked for possible resubmissions. The pooled data were evaluated with the SPSS 22.0 statistical package program. Frequency distributions were calculated and presented as n, %. RESULTS: Four hundred and six PMR, rheumatology, and algology specialists fulfilled the study forms. About 59.0% of physicians stated that they prefer duloxetine as the first-line agent of fibromyalgia syndrome (FMS) treatment. Pregabalin was only 6.0% of the physicians' first choice for FMS. About 35.0% of the participating physicians stated that the PMR department should follow up FMS patients. About 44.3% of the participants noted that they refer FMS patients to other departments which interested in FMS treatment and do not want to follow-up FMS patients. About 81% agreed that pregabalin causes addiction. About 36.7% stated that at least 20% of the patients could abuse pregabalin and 97.8% of physicians stated that they were prejudiced about prescribing pregabalin to prisoners. Approximately two of the three physicians experienced an act of violence in their hospital regarding pregabalin prescribing. CONCLUSION: These data showed that the 'Pregabalinophobia' should be accepted. This condition is associated with life safety concerns of the physician not only from unreliability of the drug. It seems that the doctors have valid reasons to develop this prejudice.

Erector spinae plane block vs interscalene brachial plexus block for postoperative analgesia management in patients who underwent shoulder arthroscopy.

BACKGROUND: Interscalene brachial plexus block (ISB) is the gold standard method used for postoperative analgesia after arthroscopic shoulder surgery. Ultrasound guided erector spinae plane block (ESPB) is an interfascial plane block. The aim of this study is to compare the analgesic efficacy of ESPB and ISB after shoulder arthroscopy. The primary outcome is the comparison of the perioperative and postoperative opioid consumptions. METHODS: Sixty patients with ASA score I-II planned for arthroscopic shoulder surgery were included in the study. ESPB was planned in Group ESPB (n = 30), and ISB was planned in Group ISB (n = 30). Intravenous fentanyl patient-controlled analgesia was administered to both groups in the postoperative period. Intraoperative and postoperative opioid and analgesic consumption of both groups, side effects and complications related to opioid use, postoperative pain scores and rescue analgesic use were recorded in the first 48 h postoperatively. RESULTS: Pain scores were significantly higher in the ESPB group in the first 4 h postoperatively than in the ISB group (p < 0.05). The total fentanyl consumption and number of patients using rescue analgesics in the postoperative period were significantly higher in the ESPB group (p < 0.05). The incidence of nausea in the postoperative period was significantly higher in the ESPB group (p < 0.05). CONCLUSIONS: In our study, it was seen that ISB provided more effective analgesia management compared to ESPB in patients underwent shoulder arthroscopy surgery.

High Thoracic Erector Spinae Plane Block for Arthroscopic Shoulder Surgery: A Randomized Prospective Double-Blind Study.

OBJECTIVE: Moderate to severe pain may occur following arthroscopic shoulder surgery. An erector spinae plane block (ESPB) may be used for painful conditions of the shoulder. The primary hypothesis of this trial is that ultrasound-guided ESPB would provide effective analgesia by reducing opioid consumption. The secondary hypothesis is that ESPB would result in low pain scores and reduce the use of rescue analgesia. DESIGN: Randomized prospective double-blind study. SETTING: Academic university hospital. SUBJECTS: Sixty patients aged between 18 and 65 years designated as American Society of Anesthesiologists (ASA) class I or II who underwent unilateral arthroscopic shoulder surgery under general anesthesia were included in the study. METHODS: Patients were equally divided into two groups-either the ESPB group (n=30) or the sham block group (n=30). ESPB was performed with 30 mL 0.25% bupivacaine at the T2 level in the ESPB group and sham block with 30 mL saline at the T2 level in the sham block group. Twenty minutes before the end of the operation, 100 mg tramadol was administered intravenously to the patients. Intravenous ibuprofen 400 mg 3 × 1 was ordered for the patients during the postoperative period. A patient control analgesia device including a dose of 10 µg/mL fentanyl was connected to the patients. RESULTS: There were no statistical differences between groups in terms of demographical data. Postoperative fentanyl consumption was significantly lower in the ESPB group than in the sham block group (96.66 µg ±105.57 µg and 230 µg ±247.17 µg, respectively) (P=0.009). The need for rescue analgesia was significantly lower in the ESPB group than in the sham block group (26.66 mg ±35.43 mg and 48.5 mg ±35.45 mg, respectively) (P=0.020). Overall, the visual analog scale scores were significantly lower in the ESPB group than in the sham block group. CONCLUSIONS: ESPB may provide effective analgesia treatment following arthroscopic shoulder surgery.

A Randomized Trial to Compare Serratus Anterior Plane Block and Erector Spinae Plane Block for Pain Management Following Thoracoscopic Surgery.

OBJECTIVE: Comparison of ultrasound (US)-guided erector spinae plane block (ESPB) and serratus anterior plane block (SAPB) in video-assisted thoracic surgery (VATS) patients. The primary outcome was to compare perioperative and postoperative (48 hours) opioid consumption. METHODS: A total of 60 patients were randomized into two groups (N = 30): an ESPB group and an SAPB group. All the patients received intravenous patient-controlled postoperative analgesia and ibuprofen 400 mg intravenously every eight hours. Visual analog scale (VAS) scores, opioid consumption, and adverse events were recorded. RESULTS: Intraoperative and postoperative opioid consumption at 0-8, 8-16, and 16-24 hours and rescue analgesic use were significantly lower in the ESPB group (P < 0.05). Static/dynamic VAS scores were significantly lower in the ESPB group (P < 0.05). There was no significant difference between static VAS scores at the fourth hour. There were no differences between adverse effects. Block procedure time and one-time puncture success were similar between groups (P > 0.05 each). CONCLUSION: US-guided ESPB may provide better pain control than SAPB after VATS. QUESTION: Even though there are studies about analgesia management after VATS, clinicians want to perform the technique that is both less invasive and more effective. FINDINGS: This randomized trial showed that US-guided ESPB provides effective analgesia compared with SAPB. MEANING: Performing single-injection ESPB reduces VAS scores and opioid consumption compared with SAPB.

Transient Horner's syndrome after single shot paravertebral block / Síndrome de Horner transitória após bloqueio paravertebral em injeção única

Abstract Background Thoracic paravertebral block can provide analgesia for unilateral chest surgery and is associated with a low complication rate. Horner syndrome also referred to as oculosympathetic paresis, is a classic neurologic constellation of ipsilateral blepharoptosis, pupillary miosis, and facial anhidrosis resulting from disruption of the sympathetic pathway supplying the head, eye, and neck. Case report We present a patient with an ipsilateral transient Horner syndrome after ultrasound guided single shot of 15 mL 0.25% levobupivacaine for thoracic paravertebral block at T5-6 level. Conclusions It should be kept in mind that even a successful ultrasound guided single shot thoracic paravertebral block can be complicated with Horner syndrome due to unpredictable distribution of the local anesthetic.

Resumo Justificativa O bloqueio paravertebral torácico pode proporcionar analgesia para cirurgia torácica unilateral e está associado a um baixo índice de complicações. A síndrome de Horner (também denominada paralisia oculossimpática) é uma constelação neurológica clássica de blefaroptose ipsilateral, miose pupilar e anidrose facial devido a distúrbio da via simpática que fornece inervação para a cabeça, os olhos e o pescoço. Relato de caso Apresentamos o caso de um paciente com síndrome de Horner transitória ipsilateral após a administração de injeção única de 15 mL de levobupivacaína a 0,25% para bloqueio paravertebral torácico ao nível de T5-6 guiado por ultrassom. Conclusões Devemos considerar que mesmo um bloqueio paravertebral torácico bem-sucedido com a administração de injeção única e guiado por ultrassom pode ser complicado com a síndrome de Horner devido à distribuição imprevisível do anestésico local.

Is saphenous nerve radio frequency an effective treatment for advanced gonarthrosis in elders with cardiac comorbidity?

BACKGROUND: Pulsed radiofrequency (PRF) used for knee pain originating from osteoarthritis is one of these methods. OBJECTIVES: The aim of the study was to evaluate the knee functional status and pain palliation following the application of pulse radiofrequency in patients with cardiac comorbid disease who were diagnosed with advanced stage osteoarthritis. METHODS: Thirty-eight patients with high surgical risk having cardiac comorbidities with grade 3-4 gonarthrosis according to the Kellgren-Lawrence classification were retrospectively analyzed. PRF was applied to the saphenous nerve of each patient. Visual Analog Scale for knee pain evaluation both at rest and on movement and the Lysholm Knee Scoring Scale for function evaluation were used. The patient status was evaluated before the procedure and at the first and sixth months after the procedure. RESULTS: The mean age was 68.8 years (range, 53-82 years). Both the rest and movement post-procedural Visual Analog Scale scores at first and sixth months were significantly lower than pre-procedural values (p< 0.001). A statistically significant improvement was also determined when pre- and one and six months post-procedural Lysholm scores were compared (p< 0.001). CONCLUSIONS: PRF is a safe and function sparing minimally invasive pain palliation method for knee osteoarthritis in elders with cardiac comorbidity.

Ultrasound-guided versus conventional injection for caudal block in children: A prospective randomized clinical study.

STUDY OBJECTIVE: The aim of this study was to compare the efficacies of ultrasound guided sacral hiatus injection and conventional sacral canal injection performed for caudal block in children. DESIGN: Randomized controlled clinical trial. SETTING: Operating rooms of university hospital of Erzurum, Turkey. PATIENTS: One hundred-thirty four children, American Society of Anesthesiologists I-II, between the ages of 5 and 12, scheduled for elective phimosis and circumcision surgery. INTERVENTIONS: Patients assigned to two groups for ultrasound guided caudal block (Group U, n=68) or conventional caudal block (Group C, n=66). Caudal solution was prepared as 0.125% levobupivacaine plus 10mcg/kg morphine (total volume: 0.5ml/kg), and was administered to both groups. MEASUREMENTS: The block performing time, the block success rate, the number of needle puncture, the success at first puncture and the complications were recorded. MAIN RESULTS: The block performing time and the success rate of block were similar between Group U and Group C (109.96±49.73s vs 103.17±45.12s, and 97% vs 93%, respectively p>0.05). The first puncture success rate was higher in Group U than in Group C (80% vs 63%, respectively p=0.026). No significant difference was observed between the groups with regard to the number of needle punctures (p=0.060). The rates of vascular puncture and subcutaneus bulging were higher in Group C than in Group U (8/66 vs 1/68, and 8/66 vs 0/68, respectively p<0.05). CONCLUSIONS: Despite the limitations in central neuroaxial anesthesia we recommend the use of ultrasound since it reduces the complications and increases the success rate of first puncture in pediatric caudal injection.

[Transient Horner's syndrome after single shot paravertebral block]. / Síndrome de Horner transitória após bloqueio paravertebral em injeção única.

BACKGROUND: Thoracic paravertebral block can provide analgesia for unilateral chest surgery and is associated with a low complication rate. Horner syndrome also referred to as oculosympathetic paresis, is a classic neurologic constellation of ipsilateral blepharoptosis, pupillary miosis, and facial anhidrosis resulting from disruption of the sympathetic pathway supplying the head, eye, and neck. CASE REPORT: We present a patient with an ipsilateral transient Horner syndrome after ultrasound guided single shot of 15mL 0.25% levobupivacaine for thoracic paravertebral block at T5-6 level. CONCLUSIONS: It should be kept in mind that even a successful ultrasound guided single shot thoracic paravertebral block can be complicated with Horner syndrome due to unpredictable distribution of the local anesthetic.