Case study of hepatic radiofrequency ablation causing a systemic inflammatory response under total intravenous anesthesia

Construction and validation of postoperative hypothermia prediction model for patients undergoing joint replacement surgery

AIM

To construct and validate a postoperative hypothermia prediction model for patients undergoing joint replacement surgery.

BACKGROUND

Postoperative hypothermia is one of the harmful perioperative complications in patients undergoing joint replacement surgery. The previous studies mainly focused on intraoperative hypothermia prediction models. The prediction model for postoperative hypothermia in patients with joint replacement surgery was understudied.

DESIGN

Cohort study.

METHODS

We collected data from 503 participants undergoing joint replacement surgery in a tertiary hospital from January 2019 to December 2021. Of those, 404 cases were assigned to the modelling and 99 to the validation groups. Logistic regression was used to construct the model. The AUC was used to test the predictive effect of the model. Finally, 99 cases were used to verify the application effect of the model. A TRIPOD checklist was used to guide the reporting of this study.

RESULTS

The factors entered into the prediction model were age, intraoperative hypothermia, BMI, heat preservation measures and platelet (PLT). The model was constructed as follows: Logit (P) = .537 + 3.669 × 1 (intraoperative hypothermia) + .030 × age - .289 × BMI + 2.857 × 1 (intraoperative insulation measures) + .003 × PLT. Hosmer-Lemeshow test, p = .608, the area under the receiver operating characteristic curve (AUC) was .861. The Youden index was .530, the sensitivity was .599 and the specificity was .93. The incidence of postoperative hypothermia in the modelling group was 42.93% (173/404), and that in the verification group was 43.43% (43/99), χ2 = .012, p = .912. The correct practical application rate was 87.88%. This model has a good application effect.

CONCLUSION

The current prediction model provided a reference for clinical screening of patients with high-risk hypothermia after joint replacement surgery.

RELEVANCE TO CLINICAL PRACTICE

Clinical nurses can use the developed prediction model to predict the occurrence of postoperative hypothermia and provide a reference for the preventive measure.

US-guided high-intensity focused ultrasound (HIFU) of abdominal tumors: outcome, early ablation-related laboratory changes and inflammatory reaction. A single-center experience from Germany

INTRODUCTION

High-intensity focused ultrasound (HIFU) is an innovative noninvasive procedure for local ablation of different benign and malignant tumors. Preliminary data of animal studies suggest an ablation-associated immune response after HIFU that is induced by cell necrosis and release of intracellular components. The aim of this study is to evaluate if a HIFU-induced early sterile inflammatory reaction is initiated after ablation of uterine fibroids (UF) and pancreatic carcinoma (PaC) which might contribute to the therapeutic effect.

MATERIAL AND METHODS

A hundred patients with PaC and 30 patients with UF underwent US-guided HIFU treatment. Serum markers of inflammation (leukocytes, CRP, IL-6) and LDH in both collectives as well as tumor markers CA 19-9, CEA and CYFRA in PaC patients were determined in sub-cohorts before and directly after HIFU (0, 2, 5 and 20 h post-ablation) as well as at 3, 6, 9 and 12 months follow-up. Peri-/post interventional imaging included contrast-enhanced MRI of both cohorts and an additional CT scan of PaC patients.

RESULTS

An early post-ablation inflammatory response was observed in both groups with a significant increase of leukocytes, CRP and LDH within the first 20 h after HIFU. Interestingly, IL-6 was increased at 20 h after HIFU in PaC patients. A significant reduction of tumor volumes was observed during one year follow-up (p < .001) for both tumor entities demonstrating effective treatment outcome.

CONCLUSION

Tumor ablation with HIFU induces an early sterile inflammation that might serve as a precondition for long-term tumor immunity and a sustainable therapeutic effect.

Irreversible Electroporation versus Radiofrequency Ablation: A Comparison of Local and Systemic Effects in a Small-Animal Model

Purpose To compare both periablational and systemic effects of two mechanistically different types of ablation: thermal radiofrequency (RF) ablation and electroporative ablation with irreversible electroporation (IRE) in appropriately selected animal models. Materials and Methods Animal experiments were performed according to a protocol approved by the Animal Care Committee of Hebrew University. Female C57BL/6 mice (n = 165) were randomized to undergo either RF or IRE ablation of noncancerous normal liver. The inflammatory response, cell proliferation, interleukin 6 (IL-6) levels, and intactness of vessels in the liver were assessed at 6, 12, and 24 hours and at 3, 7, and 14 days after ablation (n = 122 for mechanistic experiments). Systemic effects were then assessed by comparing tumor formation in an Mdr2-knockout (KO) mouse model (n = 15) and tumor growth in a remote BNL 1ME hepatoma xenograft tumor (n = 28). Results were averaged and evaluated by using two-tailed t tests. Results Although RF ablation was associated with a well-defined periablational inflammatory rim, for IRE, the infiltrate penetrated the ablation zone, largely along persistently patent vessels. Peak IL-6 levels (6 hours after ablation) were 10 and three times higher than at baseline for IRE and RF, respectively (P < .03). Mdr2-KO mice that were treated with IRE ablation had more tumors that were 3 mm or larger than mice treated with RF ablation or sham operation (mean, 3.6 ± 1.3 [standard deviation] vs 2.4 ± 1.1 and 2.2 ± 0.8, respectively; P < .05 for IRE vs both RF ablation and sham operation). For BNL 1ME tumors, both RF and IRE liver ablation reduced tumor growth, with a greater effect noted for IRE (1329 mm(3) ± 586 and 819 mm(3) ± 327 vs 2241 mm(3) ± 548 for sham operation; P < .05) that was accompanied by more infiltrating lymphocytes compared with sham operation (7.6 cells per frame ± 1.9 vs 11.2 ± 2.1 vs 0.3 ± 0.1; P < .05). Conclusion Persistent patency of vasculature within the coagulated zone from IRE increases the area and accumulation of infiltrative cells that is associated with a higher serum IL-6 level than RF ablation. These local changes of IRE induce more robust systemic effects, including both tumorigenic and immunogenic effects. (©) RSNA, 2016 Online supplemental material is available for this article.

Hepatic radiofrequency ablation causes an increase of circulating histones in patients with hepatocellular carcinoma

BACKGROUND

Radiofrequency ablation (RFA) has been increasingly accepted for the treatment of hepatocellular carcinoma (HCC). However, RFA has been associated with an obvious systemic inflammatory response, but little is known about the underlying mechanisms. Circulating histones are recently identified as pivotal inflammatory mediators. Hence, we investigated whether circulating histones are involved in RFA-related inflammation.

METHODS

Serial blood samples were collected from 42 HCC patients undergoing RFA at 3 time points: pre-RFA, post-RFA (within 24 h), and in 4-week follow up after RFA. Plasma histones, myeloperoxidase (MPO), inflammatory cytokines (IL-1β, IL-6, IL-10, TNF-α), liver damage parameters (ALT, AST), and creatinine were measured.

RESULTS

Compared to pre-RFA (0.837 μg/ml), there was a significant increase in the levels of circulating histones within 24 h post-RFA (4.576 μg/ml, p < 0.0001); histones decreased to pre-RFA levels in 4-week follow up after RFA. Meanwhile, MPO, IL-6, and IL-10 were elevated remarkably within 24 h post-RFA, indicative of an occurrence of the inflammatory response. Notably, histone levels correlated well with MPO (r = 0.5678), IL-6 (r = 0.4851), and IL-10 (r = 0.3574), respectively. In addition, there was a significant damage of liver function in patients within 24 h post-RFA, evidenced by the increased levels of ALT and AST. No changes in creatinine levels were observed.

CONCLUSIONS

These data demonstrate that circulating histones are excessively released in HCC patients treated with RFA, which may lead to systemic inflammation by stimulating neutrophil activation and promoting cytokine production. Circulating histones may act as a novel marker to indicate the extent of inflammation related to RFA.

Profound systemic inflammatory response syndrome following non-emergent intestinal surgery in children

PURPOSE

Systemic inflammatory response syndrome (SIRS) is an uncommon but severe complication in surgical patients. While SIRS is well known, it is poorly described in the pediatric population. The goal of this study was to describe the incidence of profound SIRS following non-emergent intestinal surgery in children and to identify potential risk factors.

METHODS

A retrospective review was conducted for patients 0-19 years of age following intestinal surgery and/or lysis of adhesions from 01/01/1999-02/28/2012. Children were excluded for preoperative instability or frank bowel perforation. Patients were then placed in a post-operative SIRS or non-SIRS group as defined by the 2005 International Pediatric Sepsis Consensus Conference Guidelines (6. B. Goldstein, B. Giroir, A. Randolph, and Sepsis International Consensus Conference on Pediatric, 'International Pediatric Sepsis Consensus Conference: Definitions for Sepsis and Organ Dysfunction in Pediatrics', Pediatr Crit Care Med, 6 (2005), 2-8.).

RESULTS

SIRS was identified in 17 of the 381 patients. Logistic regression analysis was performed and showed heart disease, kidney disease, PN dependence, and intestinal obstruction to be predictive of post-operative SIRS.

CONCLUSION

This study represents one of the first reports to identify a previously poorly described process of significant SIRS after intestinal surgery in children. Both systemic organ failure and intestinal dysfunction are strong risk factors for post-operative SIRS in children. Potentially, these pre-existing conditions may lead to disruption of normal intestinal flora or barrier function, which in turn may predispose these children to dramatic SIRS episodes after intestinal surgery. Understanding how these factors lead to SIRS will be critical to developing prevention strategies.

Factors related to postoperative pain among patients who underwent radiofrequency ablation of hepatocellular carcinoma

AIM

To evaluate the incidence and associated factors of postoperative intense pain and haemodynamic changes during radiofrequency ablation of hepatocellular carcinoma.

MATERIALS AND METHODS

A total of 123 consecutive hepatocellular carcinoma patients who underwent radiofrequency ablation were prospectively recruited. Patient factors, tumour characteristics, procedural factors, intraoperative haemodynamic changes, complications, postoperative events, laboratory values before and after ablation, and postoperative pain were evaluated. Postoperative pain was scored using a visual analogue scale after the procedure.

RESULTS

The mean age of the patients was 65.6 ± 9.6 years. In multiple logistic regression analysis, patients who underwent general anaesthesia [odds ratio (95% CI): 2.68 (1.23-5.81); p = 0.013] and had more postoperative nausea and vomiting episodes [3.10 (1.11-8.63); p = 0.036] were associated with intense pain. These findings remain robust after propensity score matching. For mean difference values between before and after RFA, higher in change in aspartate transaminase (p = 0.026), alanine transaminase (p = 0.016) and white blood cell count (p = 0.015), and lower in change in haemoglobin (p = 0.009) were also correlated with intense pain. There was no significant difference in haemodynamic changes between the general anaesthesia and local anaesthesia group during ablation.

CONCLUSION

General anaesthesia, postoperative nausea and vomiting, and laboratory factors were associated with postoperative intense pain in patients who underwent radiofrequency ablation. Counselling and modification of analgesics should be considered in patients with related factors for intense pain.

More than just tumor destruction: immunomodulation by thermal ablation of cancer

Over the past decades, thermoablative techniques for the therapy of localized tumors have gained importance in the treatment of patients not eligible for surgical resection. Anecdotal reports have described spontaneous distant tumor regression after thermal ablation, indicating a possible involvement of the immune system, hence an induction of antitumor immunity after thermoinduced therapy. In recent years, a growing body of evidence for modulation of both adaptive and innate immunity, as well as for the induction of danger signals through thermoablation, has emerged. Induced immune responses, however, are mostly weak and not sufficient for the complete eradication of established tumors or durable prevention of disease progression, and combination therapies with immunomodulating drugs are being evaluated with promising results. This article aims to summarize published findings on immune modulation through radiofrequency ablation, cryoablation, microwave ablation therapy, high-intensity focused ultrasound, and laser-induced thermotherapy.