Thoracic epidural bupivacaine attenuates inflammatory response, intestinal lipid peroxidation, oxidative injury, and mucosal apoptosis induced by mesenteric ischemia/reperfusion. Anesth Analg. 2011;113:1226-1232. [PMID: 21865496 DOI: 10.1213/ANE.0b013e31822b8984]

Impact of early thoracic epidural analgesia in patients with severe acute pancreatitis

OBJECTIVE

This study was designed to assess the impact of thoracic epidural analgesia (TEA) in patients with severe acute pancreatitis (SAP).

METHODS

This is a single-centre retrospective study. In this study, the outcomes of SAP patients were compared between patients received TEA (TEA group) and without TEA (NTEA group). Early TEA was defined as TEA performed within 48 hours after onset. The main outcome was the mortality at 30 days after ICU admission, and secondary outcomes included the incidence of acute respiratory distress syndrome (ARDS), the acute renal injury (AKI) and sepsis, the hospital stay and hospitalization expenses.

RESULTS

The mortality of SAP patients in TEA versus NTEA was 8.0% and 13.3% (p = .1520). Multivariate regression analysis showed significant difference in mortality between the TEA and NTEA groups (OR, 0.387; 95% CI, 0.168-0.892; p = .026). The incidence of ARDS in TEA versus NTEA was 46.0% and 62.4% (p = .0044); the proportion of patients requiring invasive ventilator assisted ventilation in TEA, and NTEA was 22.6% and 39.2% (p = .0016). The incidence of AKI in TEA versus NTEA was 27.7% and 45.3% (p = .0044); the proportion of patients needing for continuous renal replacement therapy (CRRT) in TEA and NTEA was 48.2% and 74.0% (p < .0001). The mortality of SAP patients in early TEA versus NTEA was 4.8% and 15.3% (p = .0263).

CONCLUSIONS

TEA was associated with low incidence of ARDS and AKI in patients with SAP. Early TEA may benefit mortality in SAP patients and is a possible protective factor for the mortality of SAP patients.

Effects of general anaesthesia and ultrasonography-guided interscalene block on pain and oxidative stress in shoulder arthroscopy: A randomised trial

BACKGROUND/AIM

The aim of this study was to evaluate the effects of general anaesthesia and ultrasonography-guided interscalene block on pain and oxidative stress evaluated by thiol-disulphide balance and C-reactive protein levels in patients undergoing shoulder arthroscopy.

MATERIALS AND METHODS

A total of 42 patients aged 18-75 years who were scheduled to undergo shoulder arthroscopy were randomised into interscalene block group (Group-IB, n = 20) and general anaesthesia group (Group-GA, n = 22). All patients received patient-controlled analgesia during the postoperative period. Additional analgesics were administered to patients with a visual analogue scale score of >4. Native-thiol, total-thiol, disulphide and C-reactive protein levels were measured. Patients' visual analogue scale scores, morphine and additional analgesic consumption were recorded. A shift in thiol-disulphide balance towards decreased thiol and increased disulphide levels was regarded as an indicator of oxidative stress.

RESULTS

Pain level, morphine and additional analgesic consumption were higher in Group-GA. Native-thiol and total-thiol levels were higher in Group-IB postoperatively and also disulphide levels were lower at postoperative 18 hours. C-reactive protein levels were similar in both the groups.

CONCLUSION

Interscalene block induced less oxidative stress during the postoperative period, as evaluated by thiol-disulphide balance. In shoulder arthroscopy, interscalene block provides more stable haemodynamics perioperatively and facilitates better postoperative pain control.

Melatonin attenuates lung ischaemia-reperfusion injury via inhibition of oxidative stress and inflammation

OBJECTIVES

Lung ischaemia-reperfusion injury is a complex pathophysiological process due to the production of reactive oxygen species and the generation of inflammatory reaction. We investigated the protective effects and the corresponding mechanism of melatonin (MT), a potent free-radical scavenger, on lung injury induced by ischaemia-reperfusion in a mouse model.

METHODS

Adult male C57BL/6J mice (n = 30) were randomly and equally allocated into 5 groups: sham controls, IR, IR + 10 mg/kg MT, IR + 20 mg/kg MT and IR + 30 mg/kg MT. Lung ischaemia-reperfusion injury was induced by thoracotomy followed by clamping of the left hilum for 1 h and subsequent reperfusion for 2 h.

RESULTS

Histological scoring analysis showed that lung parenchymal damage was ameliorated in the melatonin pretreatment groups when compared with the IR group, with the IR + 20 mg/kg MT group showing the strongest effect among the melatonin pretreatment groups. Wet-to-dry weight ratio, detection of malondialdehyde, protein expressions of inflammatory factors (tumour necrosis factor-α, interleukin-1β, NF-κB and IKK-γ) and apoptotic factors (cleaved caspase-3 and Bax/Bcl-2), as well as TUNEL assay showed changes similar to those of the lung injury scores in all groups. In contrast, the examination of superoxide dismutase showed a pattern contrary to that of the lung injury score in all groups. In addition, immunohistochemistry staining showed that the expressions of the antioxidants glutathione peroxidase and glutathione reductase were increased in the melatonin pretreatment groups.

CONCLUSIONS

This study demonstrated that melatonin pretreatment attenuated lung ischaemia-reperfusion injury via inhibition of oxidative stress, inflammation and apoptosis.

Thoracic epidural anaesthesia reduces insulin resistance and inflammatory response in experimental acute pancreatitis

AIMS

The activity of the sympathetic nervous system (SNS) is crucial at an early stage in the development of an inflammatory reaction. A study of metabolic events globally and locally in the early phase of acute pancreatitis (AP), implying hampered SNS activity, is lacking. We hypothesized that thoracic epidural anaesthesia (TEA) modulates the inflammatory response and alleviates the severity of AP in pigs.

MATERIAL AND METHODS

The taurocholate (TC) group (n = 8) had only TC AP. The TC + TEA group (n = 8) had AP and TEA. A control group (n = 8) underwent all the preparations, without having AP or TEA. Metabolic changes in the pancreas were evaluated by microdialysis and by histopathological examination.

RESULTS

The relative increase in serum lipase concentrations was more pronounced in the TC group than in TC + TEA and control groups. A decrease in relative tissue oxygen tension (PtiO₂) levels occurred one hour later in the TC + TEA group than in the TC group. The maintenance of normoglycaemia in the TC group required a higher glucose infusion rate than in the TC + TEA group. The relative decrease in serum insulin concentrations was most pronounced in the TC + TEA group.

CONCLUSION

TEA attenuates the development of AP, as indicated by changes observed in haemodynamic parameters and by the easier maintenance of glucose homeostasis. Further, TEA was associated with attenuated insulin resistance and fewer local pathophysiological events.

The Potential Effect of Epidural Anesthesia on Mesenteric Injury after Supraceliac Aortic Clamping in a Rabbit Model

BACKGROUND

Epidural anesthesia is known to increase blood flow by producing vasodilatation on mesenteric circulation. In this experimental study, we aim to examine the effect of epidural anesthesia on mesenteric ischemic-reperfusion (IR) injury induced by supracoeliac aortic occlusion in a rabbit model.

METHODS

Twenty-eight male white New Zealand rabbits were assigned into 4 separate groups, with 7 rabbits in each group: group I, control group; group II, IR-only group; group III, IR plus epidural anesthesia group; group IV, epidural anesthesia-only group. IR model was produced by clamping supraceliac aorta with an atraumatic vascular clamp for 60 min, followed by reperfusion for 120 min. An epidural catheter was placed via Th12-L1 intervertebral space by using open technique before aortic clamping in those assigned to epidural anesthesia. IR injury was assessed using blood markers interleukin-6 and IMA and tissue markers superoxide dismutase and malondialdehyde. Also histopathological examination was performed to evaluate the degree of injury.

RESULTS

All biochemical markers in group II were significantly elevated in comparison with the other 3 groups (p < 0.05). This was paralleled by a more severe histopathological injury in IR- only group (group II). The group receiving IR plus epidural anesthesia (group III) had lower biochemical marker levels as compared with the IR-only group (group II).

CONCLUSIONS

Mesenteric IR injury that can occur during abdominal aorta surgery can be reduced by epidural anesthesia, which is commonly used during or after major operations for pain control. Controlled clinical studies are required to evaluate these findings.

Impact of analgesic modality on stress response following laparoscopic colorectal surgery: a post-hoc analysis of a randomised controlled trial

BACKGROUND

Epidural analgesia is perceived to modulate the stress response after open surgery. This study aimed to explore the feasibility and impact of measuring the stress response attenuation by post-operative analgesic modalities following laparoscopic colorectal surgery within an enhanced recovery after surgery (ERAS) protocol.

METHODS

Data were collected as part of a double-blinded randomised controlled pilot trial at two UK sites. Patients undergoing elective laparoscopic colorectal resection were randomised to receive either thoracic epidural analgesia (TEA) or continuous local anaesthetic infusion to the extraction site via wound infusion catheter (WIC) post-operatively. The aim of this study was to measure the stress response to the analgesic modality by measuring peripheral venous blood samples analysed for serum concentrations of insulin, cortisol, epinephrine and interleukin-6 at induction of anaesthesia, at 3, 6, 12 and 24 h after the start of operation. Secondary endpoints included mean pain score in the first 48 h, length of hospital stay, post-operative complications and 30-day re-admission rates.

RESULTS

There was a difference between the TEA and WIC groups that varies across time. In the TEA group, there was significant but transient reduced level of serum epinephrine and a higher level of insulin at 3 and 6 h. In the WIC, there was a significant reduction of interleukin-6 values, especially at 12 h. There was no significant difference observed in the other endpoints.

CONCLUSIONS

There is a significant transient attenuating effect of TEA on stress response following laparoscopic colorectal surgery and within ERAS as expressed by serum epinephrine and insulin levels. Continuous wound infusion with local anaesthetic, however, attenuates cytokine response as expressed by interleukin-6.

Thoracic epidural anesthesia decreases endotoxin-induced endothelial injury

Background

The sympathetic nervous system is considered to modulate the endotoxin-induced activation of immune cells. Here we investigate whether thoracic epidural anesthesia with its regional symapathetic blocking effect alters endotoxin-induced leukocyte-endothelium activation and interaction with subsequent endothelial injury.

Methods

Sprague Dawley rats were anesthetized, cannulated and hemodynamically monitored. E. coli lipopolysaccharide (Serotype 0127:B8, 1.5 mg x kg^-1 x h^-1) or isotonic saline (controls) was infused for 300 minutes. An epidural catheter was inserted for continuous application of lidocaine or normal saline in endotoxemic animals and saline in controls. After 300 minutes we measured catecholamine and cytokine plasma concentrations, adhesion molecule expression, leukocyte adhesion, and intestinal tissue edema.

Results

In endotoxemic animals with epidural saline, LPS significantly increased the interleukin-1β plasma concentration (48%), the expression of endothelial adhesion molecules E-selectin (34%) and ICAM-1 (42%), and the number of adherent leukocytes (40%) with an increase in intestinal myeloperoxidase activity (26%) and tissue edema (75%) when compared to healthy controls. In endotoxemic animals with epidural infusion of lidocaine the values were similar to those in control animals, while epinephrine plasma concentration was 32% lower compared to endotoxemic animals with epidural saline.

Conclusions

Thoracic epidural anesthesia attenuated the endotoxin-induced increase of IL-1β concentration, adhesion molecule expression and leukocyte-adhesion with subsequent endothelial injury. A potential mechanism is the reduction in the plasma concentration of epinephrine.

Ultralow concentrations of bupivacaine exert anti-inflammatory effects on inflammation-reactive astrocytes

Bupivacaine is a widely used, local anesthetic agent that blocks voltage-gated Na(+) channels when used for neuro-axial blockades. Much lower concentrations of bupivacaine than in normal clinical use, < 10(-8)  m, evoked Ca(2+) transients in astrocytes from rat cerebral cortex, that were inositol trisphosphate receptor-dependent. We investigated whether bupivacaine exerts an influence on the Ca(2+) signaling and interleukin-1β (IL-1β) secretion in inflammation-reactive astrocytes when used at ultralow concentrations, < 10(-8)  m. Furthermore, we wanted to determine if bupivacaine interacts with the opioid-, 5-hydroxytryptamine- (5-HT) and glutamate-receptor systems. With respect to the μ-opioid- and 5-HT-receptor systems, bupivacaine restored the inflammation-reactive astrocytes to their normal non-inflammatory levels. With respect to the glutamate-receptor system, bupivacaine, in combination with an ultralow concentration of the μ-opioid receptor antagonist naloxone and μ-opioid receptor agonists, restored the inflammation-reactive astrocytes to their normal non-inflammatory levels. Ultralow concentrations of bupivacaine attenuated the inflammation-induced upregulation of IL-1β secretion. The results indicate that bupivacaine interacts with the opioid-, 5-HT- and glutamate-receptor systems by affecting Ca(2+) signaling and IL-1β release in inflammation-reactive astrocytes. These results suggest that bupivacaine may be used at ultralow concentrations as an anti-inflammatory drug, either alone or in combination with opioid agonists and ultralow concentrations of an opioid antagonist.

Tourniquet-induced ischemia-reperfusion injuries during extremity surgery at children's age: impact of anesthetic chemical structure

OBJECTIVES

The aim of this study was to determine the relationship between the antioxidant profile of anesthetics and its relation to total antioxidant capacity (TAC) of plasma in children who underwent tourniquet-induced ischemia-reperfusion (IR) injury during extremity operations.

METHODS

Children were randomized into three groups: general inhalational anesthesia with sevoflurane (group S), total intravenous anesthesia (TIVA) with propofol (group T), and regional anesthesia (group R). Venous blood samples were obtained before peripheral nerve block and induction of general anesthesia (baseline), 1 minute before tourniquet release (BTR), and 5 and 20 minutes after tourniquet release (ATR). Plasma TAC as well as antioxidant potential of propofol, thiopental, and bupivacaine were measured using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay.

RESULTS

Plasma TAC in group T was increased significantly at 20 minutes ATR in comparison with basal and BTR values, and also was significantly higher in comparison with plasma TAC in groups S and R measured at the same time point. The radical scavenging activity of anesthetics in vitro indicated that only propofol possessed a significant antioxidative activity in the reaction with DPPH radical in comparison with thiopental and bupivacaine.

DISCUSSION

These data confirm that TIVA with propofol attenuates oxidative stress related to tourniquet-induced ischaemia-reperfusion injury in children.

Effect of propofol on proliferation and apoptosis of gastric mucosal cells in gastric ischemia-reperfusion injury in mice

AIM: To observe the changes in proliferation and apoptosis of gastric mucosal cells in gastric ischemia-reperfusion (I/R) injury, and to clarify whether propofol has a gastric protection effect and the possible mechanisms involved.

METHODS: Seventy-two Kunming mice were randomly divided into four groups: sham operation group, I/R injury group, fat emulsion group, and propofol group. Except the sham operation group, I/R injury was induced in other groups by clamping the celiac artery for 30 min and allowing reperfusion for 1h. The mice were finally sacrificed to observe morphological changes and investigate gastric mucosal damage index (GMDI). The histological changes of the stomach were observed using light microscopy. The content of malondialdehyde (MDA) and activity of superoxide dismutas (SOD) in gastric mucosal cells were measured by colorimetry analysis. Immunohistochemistry and TdT-mediated d-UTP-biotin nick end-labeling (TUNEL) assay were used to observe PCNA expression and apoptosis in gastric mucosa, and the expression of Bax and Bcl-2 proteins was determined by Western blot.

RESULTS: Severe mucosal lesions induced by gastric I/R were considerably reduced following administration of propofol (25 mg/kg); mucosal and submueosal hyperemia, edema, and deep erosion were improved significantly. Compared to the I/R group, treatment with propofol significantly reduced gastric mucosal MDA content and cell apoptosis (33.9% ± 1.3% vs 60.8% ± 6.9%, P < 0.01), enhanced SOD activity, promoted cell proliferation (16.0% ± 1.8% vs 6.4% ± 1.2%, P < 0.01), and regulated Bax (0.453 ± 0.025 vs 0.268 ± 0.023, P < 0.01) and Bcl-2 (0.513 ± 0.014 vs 0.752 ± 0.015, P < 0.01) protein expression.

CONCLUSION: Propofol protects against gastric gastric I/R injury possibly by promoting gastric mucosal cell proliferation and inhibiting apoptosis.

Pretreatment with Panax notoginseng saponins protects against small intestinal ischemia-reperfusion injury in rats

AIM: To explore the mechanism underlying the protective effect of Panax notoginseng saponins (PNS) against intestinal ischemia-reperfusion injury in rats.

METHODS: A rat model of intestinal ischemia-reperfusion injury was generated. Rats were divided into four groups: sham-operation group, model control group, low- (200 mg/kg) and high-dose (400 mg/kg) PNS groups. After pretreatment with PNS, plasma levels of D-lactate and lipopolysaccharide (LPS) were determined.Samples of the liver, spleen, mesenteric lymph nodes and blood were taken for culturing aerobic bacteria. The expression of NF-κB and TNF-α in the intestine was detected by immunohistochemistry. Cell apoptosis in the intestine was detected by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) assay.

RESULTS: The number of positive bacterial cultures in the liver, spleen, mesenteric lymph nodes and blood was significantly lower in the PNS group than in the model control group (all P < 0.05). Plasma levels of D-lactate and LPS were significantly lower in the PNS group (200 mg/kg, 400 mg/kg) than in the model control group (LPS: 461 EU/L, 320 EU/L vs 570 EU/L; D-lactate: 0.37 mmol/L, 0.31 mmol/L vs 0.44 mmol/L, both P < 0.05). Treatment with PNS reduced the expression of NF-κB and TNF-α and the number of apoptotic cells in intestinal tissue (all P < 0.05).

CONCLUSION: Pretreatment with PNS protects against intestinal ischemia-reperfusion injury in rats possibly by reducing mucosal cell apoptosis and down-regulating NF-κB and TNF-α expression in the small intestine.