Role of paravertebral block anaesthesia during percutaneous transhepatic thermoablation

Combined multiple regional anesthesia for microwave ablation of liver Tumors: Initial experience

OBJECTIVE

This study aims to assess the feasibility and safety of combined multiple regional anesthesia (CMRA) as a potential strategy to decrease pain and reliance on intravenous analgesics during and after ultrasound-guided microwave ablation (US-guided-MWA) of liver tumors.

METHODS

A cohort of 75 patients with a total of 99 liver tumors who underwent US-guided-MWA of liver tumors were enrolled. These patients were randomly allocated into three groups: A, B, and C. Prior to the ablation procedure, Group A patients received a combination of hepatic hilar block (HHB), Transversus abdominis plane block (TAPB), and local anesthesia (LA). Patients in Group B were administered HHB in conjunction with LA, while those in Group C received TAPB and LA. Evaluative parameters included the Numerical Rating Scale (NRS) scores, consumption of morphine, incidence of complications, and factors influencing perioperative pain.

RESULTS

All patients successfully underwent US-guided-MWA. The peak NRS scores for pain during ablation across the three groups were 2.36 ± 1.19, 3.28 ± 1.59, and 4.24 ± 1.42 respectively (P < 0.01), while the count of patients requiring morphine were 4/25, 8/25, and 13/25 respectively (P < 0.01). Postoperative NRS scores for the three groups at 4, 8, 12, 24, and 36-hour intervals demonstrated a pattern of initial increase followed by a decrease, with the order at each interval being: Group A < Group C < Group B. Factors associated with increased pain included larger tumor size, greater number of tumors, and longer procedure and ablation time (P < 0.05). No major complications were recorded across the three groups.

CONCLUSION

CMRA offers an effective and safe modality to manage pain during and after US-guided-MWA of liver tumors.

Evaluation of paravertebral blocks in improving post-procedural pain and decreasing hospital admission after microwave ablation of liver tumors

Although ablations are performed with conscious sedation or general anesthesia, microwave ablations can be painful post procedure. Newer analgesic modalities, including regional blocks, have promoted the proliferation of less invasive anesthesia care for ablative procedures. This study evaluates whether bilateral paravertebral blocks reduce the need for additional analgesics in comparison to unilateral blocks in microwave ablations. In this retrospective study, individuals undergoing microwave ablation who underwent unilateral versus bilateral nerve blocks at a single institution from 2017 to 2019 were compared. Categorical variables were analyzed using Pearson's chi-squared tests. Comparisons of means were completed using multiple T-tests corrected using the Holm-Sidak method with α = 0.05. Regression modeling was used to identify factors related to increased MME (milligram morphine equivalent) usage and post-procedure admission rates. A total of 106 patients undergoing 112 liver MWA procedures were included in this analysis, with patients receiving either a bilateral or unilateral block. Pre-procedural characteristics demonstrated no significant differences in age or gender. Bilateral blocks were associated with decreased usage of gabapentin (14% vs. 0%, p = 0.01) and a lower rate of post-procedure admissions (OR 0.23, p = 0.003). Therefore, when using paravertebral blocks, bilateral blocks are superior to unilateral blocks, as demonstrated by decreased rates of hospital admission and reduced use of systemic neuropathic pain medication. Additionally, reducing post-procedural MME may reduce the rate of admission to the hospital.

Hepatic Plexus Nerve Block for Microwave Ablation of Hepatic Tumors

Seven patients underwent microwave ablation of hepatic tumors, using hepatic nerve plexus block. Mean visual analog score (VAS; pain on 1-10 scale) was 0.3±0.5 at baseline and 2.5±1.4, 2.6±1.4, and 2.3±0.9 at 1, 5, and 10 minutes during ablation. Two patients reported VAS ≥4 during ablation, which both improved to VAS of 3 after one rescue sedation dose; remaining patients required no additional sedation. No major complication occurred. No patient required conversation to general anesthesia.

Anesthesia for Percutaneous Radiofrequency Tumor Ablation (PRFA): A Review of Current Practice and Techniques

Percutaneous radiofrequency ablation (PRFA) of solid tumors is a minimally invasive procedure used to treat primary or metastatic cancer lesions via needle targeted thermal energy transfer. Some of the most common tumor lesions treated using PRFA include those within the liver, lungs and kidneys. Additionally, bone, thyroid, and breast lesions can also be treated. In most cases, this procedure is performed outside of the operating room in a specialized radiology suite. As a result, the clinician must adapt in many cases to the specific environmental issues attendant to providing anesthesia outside the operating room, including the lack of availability of an anesthesia machine in some cases, and frequently a lack of adequate scavenging and other specialized monitoring and equipment. At this time, routine practice and anesthetic prescriptions for PRFA can vary widely, ranging from patients receiving local anesthesia alone, to monitored anesthesia care, to regional anesthesia, to combined regional and general anesthesia. The choice of anesthetic technique will depend on tumor location and practitioner experience. This review aims to summarize the current state of the art in terms of anesthetic techniques for patients undergoing PRFA of solid tumors.

Percutaneous Radiofrequency Ablation of Pulmonary Metastasis and Thoracic Paravertebral Block Under Computed Tomographic Scan Guidance: A Case Report

Pain during and after pulmonary percutaneous radiofrequency ablation (RFA) may be severe enough to require opioids. Thoracic paravertebral block (TPVB) is a regional anesthetic technique that can relieve pain during and after abdominal or thoracic painful procedures. We report the use of TPVB to relieve postprocedural pain in a 50-year-old woman after RFA of lung metastasis. The TPVB was performed under computed tomographic guidance by the anesthesiologist. The patient was pain free (rest and mobilization) during the first postoperative 36 hours. TPVB may represent an easy, safe, and effective strategy to prevent or treat postoperative pain after pulmonary RFA.

The Utility of Peripheral Nerve Blocks in Interventional Radiology

OBJECTIVE

The aim of this article is to provide an overview of peripheral nerve blocks, the use of peripheral nerve block within and outside interventional radiology, and the complications of peripheral nerve block.

CONCLUSION

Interventional radiologists are often responsible for sedation and pain management in the majority of interventional radiology procedures. Peripheral nerve block is increasingly being used in interventional radiology.