Effects Of Thoracic Epidural Anesthesia Research Articles

Effects of epidural anesthesia and analgesia on the incidence of chronic pain after thoracoscopic lung surgery: A retrospective cohort study

ObjectiveChronic postoperative pain (CPSP) is common after thoracic surgery, even after the less invasive video-assisted thoracoscopic surgery (VATS). This study investigated the effect of thoracic epidural anesthesia (TEA) on the development of CPSP. MaterialsWe retrospectively analyzed the data of patients who underwent VATS at our center between 2020 and 2022. The enrolled patients were divided into the epidural block (EPI) and patient-controlled intravenous analgesia (PCIA) groups. A telephone questionnaire was used to collect information regarding CPSP, which was defined as a numerical rating scale (VAS) score ≥1 at 3 or 6 months postoperatively. Additionally, statistical analyses were performed to identify the risk factors for CPSP in the two groups. ResultsOverall, 894 patients completed the follow-up interviews at 3 and 6 months, with 325 and 569 patients in the PCIA and EPI groups, respectively. The incidence rates of CPSP in the PCIA group at 3 and 6 months were 16.9 % (95 % confidence interval [CI]: 9.3–32.7 %) and 13.5 % (95 % CI: 8.7–33.4 %), and 10.3 % (95 % CI: 8.1–30.5 %) and 3.6 % (95 % CI: 3.5–21.5 %) in EPI group, respectively. The incidence of CPSP at 3 months (P = 0.0048) and 6 months (P < 0.005) was statistically significant in both groups. Age and lymph node dissection were significantly associated with CPSP. ConclusionsCompared to PCIA, TEA was associated with a lower incidence of CPSP after VATS, and should be considered an important part of the analgesia regimen for patients with VATS.

Comparison of the Effects of Thoracic Epidural Analgesia in Different Levels on Intraoperative Hemodynamics in Abdominal Surgery: A Prospective Randomized Trial

Objective Our aim was to investigate the effect of thoracic epidural anesthesia (TEA) at different levels on hemodynamic parameters in elderly patients undergoing upper abdominal surgery. Materials and Methods This randomized study was conducted on 60 patients aged 65 or above undergoing upper abdominal surgery. The patients were randomized into T6-7 and T9-10 groups, with epidural catheters placed at respective intervertebral spaces. Heart rate , systolic and diastolic blood pressure , mean arterial pressure , were recorded every 5 minutes for 30 minutes after TEA and every 10 minutes intraoperatively. Confirming adequate analgesia and 30 minutes after placement of a thoracic epidural catheter, general anesthesia was induced. Postoperative respiratory function tests, time to ambulation, gastrointestinal motility and length of stay were assessed. Results Group T6-7 and T9-10 differed for SBP at minutes 5,80, and 90 (p=0.003, p=0.007, p=0.013 respectively). At the same minutes, DBP (p

Effect of thoracic epidural anesthesia on ventilator dependence in patients with severe acute pancreatitis – a PILOT randomized controlled trial

Effect of thoracic epidural anesthesia on ventilator dependence in patients with severe acute pancreatitis – a PILOT randomized controlled trial

Effect of Thoracic Epidural Anesthesia on Perioperative Neutrophil Extracellular Trapping Markers in Patients Undergoing Anesthesia and Surgery for Colorectal Cancer: A Randomized, Controlled Trial.

Neutrophil extracellular trapping (NETosis) is an immunologic mechanism strongly linked with increased metastatic risk in colorectal cancer. The authors hypothesized that patients who received propofol-epidural anesthesia (PEA) would exhibit decreases in the expression of serum neutrophil myeloperoxidase (MPO) and citrullinated histone H3 (H3Cit) levels compared with patients who received general anesthesia (GA). Colorectal cancer surgery patients were randomly assigned to the PEA (n = 30) or GA (n = 30) group. Serum MPO, H3Cit, and metalloproteinase-9 (MMP-9) levels before surgery and 24 h after surgery were measured, and visual analogue scale (VAS) scores were recorded. The patients who received PEA showed decreases in MPO (28.06 ± 11.23 vs 20.54 ± 7.29 ng/ ml; P = 0.004) and H3Cit [3.22 ± 0.86 vs 2.73 ± 0.94 ng/ ml; P = 0.042) 24 h after surgery compared with the patients subjected to GA. In addition, there was no difference in MMP-9 levels (75.98 ± 26.9 vs 73.45 ± 28.4 ng/ ml; P = 0.726). The visual analogue scale scores 2 h and 24 h after operation were significantly lower in PEA group (P < 0.05). The number of postoperative analgesia pump pressings and sufentanil consumptions within 48 h after surgery were significantly lower in the PEA group (P < 0.001). Propofol-epidural anesthesia reduces the expression of NETosis (MPO and H3Cit) in serum during colorectal cancer surgery. ChiCTR2200066708 ( www.chictr.org.cn ).

Effect of thoracic epidural anesthesia on postoperative outcome in major liver surgery: a retrospective cohort study

PurposePostoperative complications after major liver surgery are common. Thoracic epidural anesthesia may provide beneficial effects on postoperative outcome. We strove to compare postoperative outcomes in major liver surgery patients with and without thoracic epidural anesthesia.MethodsThis was a retrospective cohort study in a single university medical center. Patients undergoing elective major liver surgery between April 2012 and December 2016 were eligible for inclusion. We divided patients into two groups according to whether or not they had thoracic epidural anesthesia for major liver surgery. The primary outcome was postoperative hospital length of stay, i.e., from day of surgery until hospital discharge. Secondary outcomes included 30-day postoperative mortality and major postoperative complications. Additionally, we investigated the effect of thoracic epidural anesthesia on perioperative analgesia doses and the safety of thoracic epidural anesthesia.ResultsOf 328 patients included in this study, 177 (54.3%) received thoracic epidural anesthesia. There were no clinically important differences in postoperative hospital length of stay (11.0 [7.00–17.0] vs. 9.00 [7.00–14.0] days, p = 0.316, primary outcome), death (0.0 vs. 2.7%, p = 0.995), or the incidence of postoperative renal failure (0.6 vs. 0.0%, p = 0.99), sepsis (0.0 vs. 1.3%, p = 0.21), or pulmonary embolism (0.6 vs. 1.4%, p = 0.59) between patients with or without thoracic epidural anesthesia. Perioperative analgesia doses — including the intraoperative sufentanil dose (0.228 [0.170–0.332] vs. 0.405 [0.315–0.565] μg·kg−1·h−1, p < 0.0001) — were lower in patients with thoracic epidural anesthesia. No major thoracic epidural anesthesia-associated infections or bleedings occurred.ConclusionThis retrospective analysis suggests that thoracic epidural anesthesia does not reduce postoperative hospital length of stay in patients undergoing major liver surgery — but it may reduce perioperative analgesia doses. Thoracic epidural anesthesia was safe in this cohort of patients undergoing major liver surgery. These findings need to be confirmed in robust clinical trials.

Thoracic epidural anaesthesia vs intrathecal morphine in dogs undergoing major thoracic and abdominal surgery: clinical study

BackgroundThere is scant clinical research on neuraxial analgesia in dogs undergoing major surgery. With this study we compared the perioperative analgesic effects of thoracic epidural anaesthesia (TEA) and intrathecal morphine (ITM) in dogs scheduled for thoracic or cranial abdominal surgery. The dogs received methadone and dexmedetomidine, were anaesthetized with propofol maintained with sevoflurane, and randomly assigned to receive either TEA (ropivacaine 0.5% at 0.2 mg/kg and morphine 0.1 mg/kg administered at T12-T13) or ITM (morphine 30 μg/kg administered at L6-L7). Intraoperative rescue analgesia (iRA) was fentanyl 1 μg/kg administered if heart rate or mean arterial pressure increased by 30% above the pre-stimulation level. Glasgow Pain Composite Scale score (GPCS) dictated the use of postoperative rescue analgesia (pRA) with methadone 0.2 mg/kg.ResultsThere was a statistically significant difference in iRA, median time to first fentanyl bolus, median fentanyl dose after surgical opening, and median GPCS score at 30 minutes (min), 1 ,2, 4, 6, and 8 hours (h) between the two groups (p<0.001; p<0.001; p<0.001; p<0.01; p<0.01; p<0.001; p<0.01; p=0.01; p=0.01, respectively). Fewer TEA than ITM group dogs required iRA during surgical opening and pRA: 5% (1/18) and 2/18 (11%), respectively, in the TEA and 83% (16/18) and 10/18 (55%), respectively, in the ITM group. Side effects were urinary retention in 3/18 (16%) TEA group dogs and 2/18 (11%) ITM group dogs and prolonged sedation in 2/18 (11%) in ITM group dogs.TEA and ITM were effective in managing perioperative pain in dogs undergoing thoracic or cranial abdominal surgery.

Beneficial Effects of Thoracic Epidural Anesthesia on Mortality Rate in Geriatric Patients after Elective Surgery for Colon Cancer: A Study of 215 Consecutive Patients

Beneficial Effects of Thoracic Epidural Anesthesia on Mortality Rate in Geriatric Patients after Elective Surgery for Colon Cancer: A Study of 215 Consecutive Patients

Effects of Thoracic Epidural Anesthesia on Systemic and Local Inflammatory Responses in Patients Undergoing Lung Cancer Surgery: A Randomized Controlled Trial

Inflammatory responses play major roles in the development of acute lung injury following lung cancer surgery. The authors tested the hypothesis that thoracic epidural anesthesia (TEA) during surgery could attenuate both systemic and local inflammatory cytokine productions in patients undergoing lung cancer surgery. A prospective randomized controlled trial. At Keio University Hospital, Tokyo, Japan. Patients scheduled for lung cancer surgery. Sixty patients were randomly allocated into two groups (n = 30 each group): the epidural group (group E), in which anesthesia was maintained with propofol, fentanyl, rocuronium, and epidural anesthesia with 0.25% levobupivacaine; or the remifentanil group (group R), in which a remifentanil infusion was used as a potent analgesia instead of epidural anesthesia. The lung epithelial lining fluid (ELF) and blood sampling were collected prior to one-lung ventilation (OLV) initiation (T1) and at 30 minutes after the end of OLV (T2). The concentrations of tumor necrosis factor (TNF)-α, interleukin (IL)-6, and IL-10 in the ELF at T2 were increased significantly compared with those at T1 in both groups. The ELF concentration of IL-6 in group E was significantly lower than that in group R at T2 (median [interquartile range]: 39.7 [13.8-80.2] versus 76.1 [44.9-138.2], p = 0.008). Plasma IL-6 concentrations at T2, which increased in comparison to that at T1, were not significantly different between the two groups. The plasma concentrations of TNF-α did not change in both groups. This randomized clinical trial suggested that TEA could attenuate local inflammatory responses in the lungs during lung cancer surgery.

The Analgesic Effects of Thoracic Paravertebral Block versus Thoracic Epidural Anesthesia After Thoracoscopic Surgery: A Meta-Analysis.

BackgroundTo date, there is no definitive evidence for the analgesic effects and side effects of thoracic epidural anesthesia (TEA) versus thoracic paravertebral block (TPVB) after thoracoscopic surgery. In this study, we conducted a meta-analysis of published randomized clinical trials (RCTs) to analyze the analgesic effects of TEA versus TPVB after thoracoscopic surgery.MethodsWe systematically searched RCTs published by October 26, 2020, in PubMed, EMBASE, and Cochrane library and conducted a meta-analysis to analyze the analgesic effects of TEA versus TPVB after thoracoscopic surgery. The primary measure was postoperative pain score, and the secondary measures were postoperative 24-hour usage of opioids, hypotension, postoperative nausea, and vomiting.ResultsA total of 458 patients from five RCTs were included in this study. After thoracoscopic surgery, the numerical rating scale (NRS) score for resting pain was higher in the TPVB group than in the TEA group at 1–2 hours and 4–6 hours after surgery (MD = 0.44, 95% CI = 0.24 to 0.64, P < 0.0001, I2 = 0%; MD = 0.47, 95% CI = 0.23 to 0.70, P < 0.0001, I2 = 0%). The postoperative 24-hour usage of morphine was higher in the TPVB group than in the TEA group (SMD = 0.67; 95% CI = 0.03 to 1.31; P = 0.04; I2 = 84%). The incidence of hypotension was significantly lower in the TPVB group than in the TEA group (OR = 4.52; 95% CI = 2.03 to 10.10; P = 0.0002; I2 = 0%). No significant between-group difference was observed in postoperative nausea and vomiting (PONV).ConclusionCompared with TPVB, TEA provides statistically significant but clinically unimportant short-term benefits following thoracoscopic surgery.

Effects of Thoracic Epidural Anesthesia on Neuronal Cardiac Regulation and Cardiac Function

Cardiac sympathetic blockade with high-thoracic epidural anesthesia is considered beneficial in patients undergoing major surgery because it offers protection in ischemic heart disease. Major outcome studies have failed to confirm such a benefit, however. In fact, there is growing concern about potential harm associated with the use of thoracic epidural anesthesia in high-risk patients, although underlying mechanisms have not been identified. Since the latest review on this subject, a number of clinical and experimental studies have provided new information on the complex interaction between thoracic epidural anesthesia-induced sympatholysis and cardiovascular control mechanisms. Perhaps these new insights may help identify conditions in which benefits of thoracic epidural anesthesia may not outweigh potential risks. For example, cardiac sympathectomy with high-thoracic epidural anesthesia decreases right ventricular function and attenuates its capacity to cope with increased right ventricular afterload. Although the clinical significance of this pathophysiologic interaction is unknown at present, it identifies a subgroup of patients with established or pending pulmonary hypertension for whom outcome studies are needed. Other new areas of interest include the impact of thoracic epidural anesthesia-induced sympatholysis on cardiovascular control in conditions associated with increased sympathetic tone, surgical stress, and hemodynamic disruption. It was considered appropriate to collect and analyze all recent scientific information on this subject to provide a comprehensive update on the cardiovascular effects of high-thoracic epidural anesthesia and cardiac sympathectomy in healthy and diseased patients.This review provides a comprehensive update on the cardiovascular effects of high-thoracic epidural anesthesia and cardiac sympathectomy in healthy and diseased patients.

Comparison of the Effects of Thoracic Epidural Anesthesia with General Anesthesia on Hemodynamic Changes and its Complications in Patients Undergoing Laparoscopic Cholecystectomy.

Background:Epidural anesthesia (EA) today has been used extensively in surgical procedures and the management of pain associated with midwifery and chronic pain. This type of anesthesia can be done in different technical, physiological, and pharmacological ways. The aim of this study was to compare the effects of thoracic EA with general anesthesia (GA) on hemodynamic changes and its complications in patients underwent laparoscopic colonoscopy.Materials and Methods:This clinical trial study was conducted on 80 patients undergoing laparoscopic cholecystectomy with EA or GA based on inclusion and exclusion criteria. The patients were randomly divided into two groups of 40 and changes in blood pressure, systolic blood pressure (SBP) and diastolic blood pressure (DBP), heart rate (HR), and arterial blood oxygen saturation were measured. The incidence of nausea, vomiting, chills, and itching in the two groups was recorded. The analysis was performed descriptively and also using t-test and Chi-square tests.Results:The results showed that the mean of SBP and DBP, HR, and arterial blood oxygen saturation and the incidence of nausea and vomiting was statistically significant (P < 0.05) between the two groups at 4, 6, and 12 h after anesthesia and it was higher in a group of GA. There was no significant difference in shivering and itching between the two groups (P > 0.05).Conclusion:The results of this study indicated that thoracic EA in patients with laparoscopic cholecystectomy has significant effects on factors such as SBP and DBP and arterial blood oxygen saturation. Furthermore, EA has fewer complications than GA, and it is the preferable approach.

Effect of Thoracic Epidural Anesthesia in a Rat Model of Phrenic Motor Inhibition after Upper Abdominal Surgery.

WHAT THIS ARTICLE TELLS US THAT IS NEW: BACKGROUND:: One important example of impaired motor function after surgery is diaphragmatic dysfunction after upper abdominal surgery. In this study, the authors directly recorded efferent phrenic nerve activity and determined the effect of the upper abdominal incision. The authors hypothesized that phrenic motor output would be decreased after the upper abdominal incision; it was also hypothesized that blocking sensory input from the incision using thoracic epidural anesthesia would diminish this incision-induced change in phrenic motor activity. Efferent phrenic activity was recorded 1 h to 10 days after upper abdominal incision in urethane-anesthetized rats. Ventilatory parameters were measured in unanesthetized rats using whole-body plethysmography at multiple time points after incision. The authors then determined the effect of thoracic epidural anesthesia on phrenic nerve activity and ventilatory parameters after incision. Phrenic motor output remained reduced by approximately 40% 1 h and 1 day after incision, but was not different from the sham group by postoperative day 10. One day after incision (n = 9), compared to sham-operated animals (n = 7), there was a significant decrease in spike frequency area-under-the-curve (median [interquartile range]: 54.0 [48.7 to 84.4] vs. 97.8 [88.7 to 130.3]; P = 0.0184), central respiratory rate (0.71 [0.63 to 0.79] vs. 0.86 [0.82 to 0.93]/s; P = 0.0460), and inspiratory-to-expiratory duration ratio (0.46 [0.44 to 0.55] vs. 0.78 [0.72 to 0.93]; P = 0.0023). Unlike humans, a decrease, not an increase, in breathing frequency has been observed after the abdominal incision in whole-body plethysmography. Thoracic epidural anesthesia attenuated the incision-induced changes in phrenic motor output and ventilatory parameters. Upper abdominal incision decreased phrenic motor output and ventilatory parameters, and this incision-induced impairment was attenuated by thoracic epidural anesthesia. The authors' results provide direct evidence that afferent inputs from the upper abdominal incision induce reflex inhibition of phrenic motor activity.

Effects of Thoracic Epidural Anaesthesia on the Serosal Microcirculation of the Human Small Intestine.

The effect of thoracic epidural analgesia (TEA) on splanchnic blood flow during abdominal surgery remains unclear. The purpose of this study was to examine whether the hemodynamic effects of TEA resulted in microcirculatory alterations to the intestinal serosa, which was visualized using incident dark-field (IDF) videomicroscopy. An observational cohort study was performed. In 18 patients, the microcirculation of the intestinal serosa was visualized with IDF. Microcirculatory and hemodynamic measurements were performed prior to (T1) and after administering a bolus of levobupivacaine (T2). If correction of blood pressure was indicated, a third measurement was performed (T3). The following microcirculatory parameters were calculated: microvascular flow index, proportion of perfused vessels, perfused vessel density and total vessel density. Data are presented as median [IQR]. Mean arterial pressure decreased from 73mmHg (68-83) at T1 to 63mmHg (±11) at T2 (p = 0.001) with a systolic blood pressure of 114mmHg (98-128) and 87 (81-97), respectively (p = 0.001). The microcirculatory parameters of the bowel serosa, however, were unaltered. In seven patients, blood pressure was corrected to baseline values from a MAP of 56mmHg (55-57), while microcirculatory parameters remained constant. We examined the effects of TEA on the intestinal serosal microcirculation during abdominal surgery using IDF imaging for the first time in patients. Regardless of a marked decrease in hemodynamics, microcirculatory parameters of the bowel serosa were not significantly affected. ClinicalTrials.gov identifier NCT02688946.

Effect of Thoracic Epidural Anesthesia on Ventricular Excitability in a Porcine Model.

Imbalances in the autonomic nervous system, namely, excessive sympathoexcitation, contribute to ventricular tachyarrhythmias. While thoracic epidural anesthesia clinically suppresses ventricular tachyarrhythmias, its effects on global and regional ventricular electrophysiology and electrical wave stability have not been fully characterized. The authors hypothesized that thoracic epidural anesthesia attenuates myocardial excitability and the proarrhythmic effects of sympathetic hyperactivity. Yorkshire pigs (n = 15) had an epidural catheter inserted (T1 to T4) and a 56-electrode sock placed on the heart. Myocardial excitability was measured by activation recovery interval, dispersion of repolarization, and action potential duration restitution at baseline and during programed ventricular extrastimulation or left stellate ganglion stimulation, before and 30 min after thoracic epidural anesthesia (0.25% bupivacaine). After thoracic epidural anesthesia infusion, there was no change in baseline activation recovery interval or dispersion of repolarization. During programmed ventricular extrastimulation, thoracic epidural anesthesia decreased the maximum slope of ventricular electrical restitution (0.70 ± 0.24 vs. 0.89 ± 0.24; P = 0.021) reflecting improved electrical wave stability. Thoracic epidural anesthesia also reduced myocardial excitability during left stellate ganglion stimulation-induced sympathoexcitation through attenuated shortening of activation recovery interval (-7 ± 4% vs. -4 ± 3%; P = 0.001), suppression of the increase in dispersion of repolarization (313 ± 293% vs. 185 ± 234%; P = 0.029), and reduction in sympathovagal imbalance as measured by heart rate variability. Our study describes the electrophysiologic mechanisms underlying antiarrhythmic effects of thoracic epidural anesthesia during sympathetic hyperactivity. Thoracic epidural anesthesia attenuates ventricular myocardial excitability and induces electrical wave stability through its effects on activation recovery interval, dispersion of repolarization, and the action potential duration restitution slope.

Effect of thoracic epidural anesthesia on heart rate variability in a porcine model.

Heart rate variability (HRV) is increasingly recognized as a means of evaluating autonomic tone. Thoracic epidural anesthesia (TEA) has been previously demonstrated to suppress the electrical storms in patients. However, the effect of TEA on HRV during sympathoexcitation remains unknown. In this study, we aimed to determine the effects of TEA on HRV response to left stellate ganglion stimulation (LSS) in a porcine model. In 12 anesthetized pigs after insertion of an epidural catheter to T1 level, a median sternotomy was performed to expose the heart and the left stellate ganglion. A 56‐electrode sock was used for obtaining epicardial activation recovery interval (ARI). Animal received LSS at 4 Hz for 30 sec. After 30 min of bupivacaine epidural injection, LSS was performed in the same way as the baseline condition. LSS significantly increased low‐frequency normalized units (LF: 44.9 ± 6.7 vs. 13.6 ± 3.1 msec2 baseline, P < 0.05) and decreased high‐frequency normalized units (HF: 11.5 ± 4.6 vs. 41.9 ± 5.1 msec2 baseline, P < 0.05). As a result, LF/HF significantly increased from 0.3 ± 0.2 to 3.9 ± 1.4 during LSS. TEA significantly attenuated the LF/HF from 3.9 ± 1.4 to 1.6 ± 0.8 with increased HF components from 11.5 ± 4.6 to 26.5 ± 3.2 msec2. LF component significantly correlates with global ARI (r = −0.81) and dispersion of repolarization (r = 0.85). HRV can precisely reflect the cardiac autonomic tone and TEA modulates the HRV by enhancing the HF components probably through a parasympathetic nerve system.

Effects of Thoracic Epidural Anesthesia on Hemodynamic Changes Induced by Hypercapnia during Sevoflurane Anesthesia

Objective: Many studies have demonstrated that carbon dioxide has direct depressive effects on the myocardium and dilates the vascular bed. However, it leads to an increase in arterial blood pressure and cardiac output because of sympathetic stimulating effect. Extensive epidural block may impair the sympathetic innervation to the heart as well as to the adrenal gland. The present study was set up in order to investigate how an extensive epidural block would affect the hemodynamic response to sympathetic stimulation induced by hypercapnia. Methods: Twenty patients were mechanically ventilated under general anesthesia after epidural catheter insertion on T6–T7 intervertebral space. Hypercapnia was obtained by CO2 breathing. PaCO2 (partial pressure of CO2, arterial) was adjusted to 30, 45, and 60 mm Hg with each concentration being maintained for 10 minutes. In each period, hemodynamic variables were monitored by pulmonary artery catheter. After returning to normocarbia for 15 minutes, 20 mL of 0.375% ropivacaine was injected epidurally and PaCO2 was adjusted in the same manner, and then, the hemodynamic variables of each period were checked. Results: There were no changes in mean arterial pressure and heart rate by hypercapnia after combined epidural anesthesia compared with general anesthesia only. Hypercapnia increased cardiac output and cardiac index. Systemic vascular resistance was decreased significantly. Pulmonary artery pressure was increased but not significantly. The degrees of hemodynamic changes were similar between in general anesthesia alone and in combined epidural anesthesia. Conclusion: In spite of an extensive epidural block, hemodynamic changes induced by hypercarbnia were not changed. There are some ‘escaped’ sympathetic nerve fibers.

Thoracic Epidural Anesthesia Reduces Right Ventricular Systolic Function With Maintained Ventricular-Pulmonary Coupling.

Blockade of cardiac sympathetic fibers by thoracic epidural anesthesia may affect right ventricular function and interfere with the coupling between right ventricular function and right ventricular afterload. Our main objectives were to study the effects of thoracic epidural anesthesia on right ventricular function and ventricular-pulmonary coupling. In 10 patients scheduled for lung resection, right ventricular function and its response to increased afterload, induced by temporary, unilateral clamping of the pulmonary artery, was tested before and after induction of thoracic epidural anesthesia using combined pressure-conductance catheters. Thoracic epidural anesthesia resulted in a significant decrease in right ventricular contractility (ΔESV25: +25.5 mL, P=0.0003; ΔEes: -0.025 mm Hg/mL, P=0.04). Stroke work, dP/dtMAX, and ejection fraction showed a similar decrease in systolic function (all P<0.05). A concomitant decrease in effective arterial elastance (ΔEa: -0.094 mm Hg/mL, P=0.004) yielded unchanged ventricular-pulmonary coupling. Cardiac output, systemic vascular resistance, and mean arterial blood pressure were unchanged. Clamping of the pulmonary artery significantly increased afterload (ΔEa: +0.226 mm Hg/mL, P<0.001). In response, right ventricular contractility increased (ΔESV25: -26.6 mL, P=0.0002; ΔEes: +0.034 mm Hg/mL, P=0.008), but ventricular-pulmonary coupling decreased (Δ(Ees/Ea) = -0.153, P<0.0001). None of the measured indices showed significant interactive effects, indicating that the effects of increased afterload were the same before and after thoracic epidural anesthesia. Thoracic epidural anesthesia impairs right ventricular contractility but does not inhibit the native positive inotropic response of the right ventricle to increased afterload. Right ventricular-pulmonary arterial coupling was decreased with increased afterload but not affected by the induction of thoracic epidural anesthesia. URL: http://www.trialregister.nl/trialreg/admin/rctview.asp?TC=2844. Unique identifier: NTR2844.

Protective effects of thoracic epidural anesthesia on hypoxia-induced acute lung injury in rabbits.

The mechanism underlying the effect of thoracic epidural anesthesia (TEA) on hypoxia-induced acute lung injury (ALI) is currently unknown. In the present study, a rabbit acute lung injury model was established to investigate the effects of TEA on inflammatory factors, pulmonary surfactant and ultrastructure. A total of 56 rabbits were randomly assigned to four groups (n=14 per group): Control group (Group C), hypoxia group (Group H), sevoflurane group (Group S) and combined sevoflurane-epidural anesthesia group (Group ES). The ALI model was considered to have been successfully induced when the ratio of arterial oxygen partial pressure to fractional inspired oxygen was <300. The correct placement of a catheter for TEA was confirmed using epidurography. ALI was maintained for 3 h. Arterial blood samples were collected from all groups during spontaneous breathing (T0) and at 3 h after ALI induction (T5) in order to evaluate the serum levels of interleukin (IL)-6, IL-8 and IL-10. Bronchoalveolar lavage fluid was harvested to determine the total phospholipid, saturated phosphatidylcholine and total protein levels. Furthermore, the dry/wet weight ratio and the mRNA expression levels of IL-6, IL-8 and IL-10 in the lung tissue were determined using ELISA. In addition, light and transmission electron microscopy and histological techniques were used to examine the morphology of alveolar type II cells in the rat lung tissue. The results indicate that changes of serum IL-6, IL-8 and IL-10 levels following ALI were consistent with the changes in the mRNA expression levels of IL-6, IL-8 and IL-10 in the lung tissue. TEA attenuated these changes and thus reduced the severity of the ALI. In addition, TEA improved the alveolar structure, reduced the number of polymorphonuclear cells and mitigated the damage of lamellar bodies. In summary, the results of the present study indicate that TEA reduces lung tissue damage by inhibiting systemic and local inflammation, decreasing the inactivation of pulmonary surfactant and improving the alveolar ultrastructure following ALI.

The effects of epidural bupivacaine on ischemia/reperfusion-induced liver injury.

Several animal studies showed beneficial effects of thoracic epidural anesthesia (TEA) in hippocampal, mesenteric and myocardial IR injury (2-4). In this study, we investigated the effects of epidural bupivacaine on hepatic ischemia reperfusion injury in a rat model. Eighteen rats were randomly divided into three groups each containing 6 animals. The rats in Group C had sham laparotomy. The rats in the Group S were subjected to liver IR through laparotomy and 20 mcg/kg/h 0.9% NaCl was administered to these rats via an epidural catheter. The rats in the Group B were subjected to liver IR and were given 20 mcg/kg/h bupivacaine via an epidural catheter. Liver tissue was harvested for MDA analysis, apoptosis and histopathological examination after 60 minutes of ischemia followed by 360 minutes of reperfusion. Blood samples were also collected for TNF-α, IL-1β, AST and ALT analysis. The AST and ALT levels were higher in ischemia and reperfusion group, which received only normal saline via the thoracic epidural catheter, compared to the sham group. In the ischemia reperfusion group, which received bupivacaine via the epidural catheter, IL-1 levels were significantly higher than in the other groups. TNF-α levels were higher in the Groups S and B compared to the sham group. Bupivacaine administration induced apoptosis in all animals. These results showed that thoracic epidural bupivacaine was not a suitable agent for preventing inflammatory response and lipid peroxidation in experimental hepatic IR injury in rats. Moreover, epidural bupivacaine triggered apoptosis in hepatocytes. Further research is needed as there are no studies in literature investigate the effects of epidural bupivacaine on hepatic ischemia reperfusion injury (Tab. 3, Fig. 3, Ref. 34).

Thoracic epidural analgesia reduces gastric microcirculation in the pig.

BackgroundThoracic epidural analgesia (TEA) is used for pain relief during and after abdominal surgery, but the effect of TEA on the splanchnic microcirculation remains debated. We evaluated whether TEA affects splanchnic microcirculation in the pig.MethodsSplanchnic microcirculation was assessed in nine pigs prior to and 15 and 30 min after induction of TEA. Regional blood flow was assessed by neutron activated microspheres and changes in microcirculation by laser speckle contrast imaging (LSCI).ResultsAs assessed by LSCI 15 min following TEA, gastric arteriolar flow decreased by 22 % at the antrum (p = 0.020) and by 19 % at the corpus (p = 0.029) of the stomach. In parallel, the microcirculation decreased by 19 % at the antrum (p = 0.015) and by 20 % at the corpus (p = 0.028). Reduced arteriolar flow and microcirculation at the antrum was confirmed by a reduction in microsphere assessed regional blood flow 30 min following induction of TEA (p = 0.048). These manifestations took place along with a drop in systolic blood pressure (p = 0.030), but with no significant change in mean arterial pressure, cardiac output, or heart rate.ConclusionThe results indicate that TEA may have an adverse effect on gastric arteriolar blood flow and microcirculation. LSCI is a non-touch technique and displays changes in blood flow in real-time and may be important for further evaluation of the concern regarding the effect of thoracic epidural anesthesia on gastric microcirculation in humans.Trial registrationsNot applicable, non-human study.