Zhi-Jie Lu

Controlled low central venous pressure reduces blood loss and transfusion requirements in hepatectomy

AIM To evaluate the effect of low central venous pressure (LCVP) on blood loss and blood transfusion in patients undergoing hepatectomy. METHODS Electronic databases and bibliography lists were searched for potential articles. A meta-analysis of all randomized controlled trials (RCTs) investigating LCVP in hepatectomy was performed. The following three outcomes were analyzed: blood loss, blood transfusion and duration of operation. RESULTS Five RCTs including 283 patients were assessed. Meta-analysis showed that blood loss in the LCVP group was significantly less than that in the control group (MD = -391.95, 95%CI: -559.35--224.56, P < 0.00001). In addition, blood transfusion in the LCVP group was also significantly less than that in the control group (MD = -246.87, 95%CI: -427.06--66.69, P = 0.007). The duration of operation in the LCVP group was significantly shorter than that in the control group (MD = -18.89, 95%CI: -35.18--2.59, P = 0.02). Most studies found no significant difference in renal and liver function between the two groups. CONCLUSION Controlled LCVP is a simple and effective technique to reduce blood loss and blood transfusion during liver resection, and appears to have no detrimental effects on liver and renal function.

A Comparison of Liver Function After Hepatectomy with Inflow Occlusion Between Sevoflurane and Propofol Anesthesia

BACKGROUND:In this study, we compared liver function tests after hepatectomy with inflow occlusion as a function of propofol versus sevoflurane anesthesia. METHODS:One hundred patients undergoing elective liver resection with inflow occlusion were randomized into a sevoflurane group or a propofol group. General anesthesia was induced with 3 &mgr;g/kg fentanyl, 0.2 mg/kg cisatracurium, and target-controlled infusion of propofol, set at a plasma target concentration of 4 to 6 &mgr;g/mL, or sevoflurane initially started at 8%. Anesthesia was maintained with target-controlled infusion of propofol (2–4 &mgr;g/mL) or sevoflurane (1.5%–2.5%). The primary end point was postoperative liver injury assessed by peak values of liver transaminases. RESULTS:Transaminase levels peaked between the first and the third postoperative day. Peak alanine aminotransferase was 504 and 571 U/L in the sevoflurane group and the propofol group, respectively. Peak aspartate aminotransferase was 435 U/L after sevoflurane and 581 U/L in the propofol group. There were no significant differences in peak alanine aminotransferase or peak aspartate aminotransferase between groups. Other liver function tests including bilirubin and alkaline phosphatase, and peak values of white blood cell counts and creatinine, were also not different between groups. CONCLUSIONS:Sevoflurane and propofol anesthetics resulted in similar patterns of liver function tests after hepatectomy with inflow occlusion. These data suggest that the 2 anesthetics are equivalent in this clinical context.

Citation classics in main pain research journals.

The number of citations of an article in scientific journals reflects its impact on a specific biomedical field and its recognition in the scientific community. In the present study, we identified and analyzed the characteristics of the 100 most frequently cited articles published between 1970 and 2010 in journals pertaining to pain research and related fields. These articles were identified using the database of the Science Citation Index (1970 to present). The most cited article received 3,017 citations and the least cited article received 302 citations, with a mean of 585 citations per article. These citation classics were published in six high-impact journals, led by Pain (84 articles). Of the 100 articles, 39 were observational studies, 25 were review articles, and 20 concerned basic science. The articles originated from 14 countries, with the United States contributing 47 articles; 67 institutions produced these 100 top-cited articles, led by National Institutes of Health of the United States (8 articles) and University College London (6 articles); 18 persons authored 2 or more of the top-cited articles. This analysis of the top citation classics allows for the recognition of major advances in pain research and gives a historical perspective on the scientific progress of this specialty.

Intrathecal Infusion of Hydrogen-Rich Normal Saline Attenuates Neuropathic Pain via Inhibition of Activation of Spinal Astrocytes and Microglia in Rats

Background Reactive oxygen and nitrogen species are key molecules that mediate neuropathic pain. Although hydrogen is an established antioxidant, its effect on chronic pain has not been characterized. This study was to investigate the efficacy and mechanisms of hydrogen-rich normal saline induced analgesia. Methodology/Principal findings In a rat model of neuropathic pain induced by L5 spinal nerve ligation (L5 SNL), intrathecal injection of hydrogen-rich normal saline relieved L5 SNL-induced mechanical allodynia and thermal hyperalgesia. Importantly, repeated administration of hydrogen-rich normal saline did not lead to tolerance. Preemptive treatment with hydrogen-rich normal saline prevented development of neuropathic pain behavior. Immunofluorochrome analysis revealed that hydrogen-rich normal saline treatment significantly attenuated L5 SNL-induced increase of 8-hydroxyguanosine immunoreactive cells in the ipsilateral spinal dorsal horn. Western blot analysis of SDS/PAGE-fractionated tyrosine-nitrated proteins showed that L5 SNL led to increased expression of tyrosine-nitrated Mn-containing superoxide dismutase (MnSOD) in the spinal cord, and hydrogen-rich normal saline administration reversed the tyrosine-nitrated MnSOD overexpression. We also showed that the analgesic effect of hydrogen-rich normal saline was associated with decreased activation of astrocytes and microglia, attenuated expression of interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) in the spinal cord. Conclusion/Significance Intrathecal injection of hydrogen-rich normal saline produced analgesic effect in neuropathic rat. Hydrogen-rich normal saline-induced analgesia in neuropathic rats is mediated by reducing the activation of spinal astrocytes and microglia, which is induced by overproduction of hydroxyl and peroxynitrite.

Assessing the national productivity in subspecialty critical care medicine journals: A bibliometric analysis ☆ ☆☆

PURPOSE In recent years, significant growth has been seen in the subspecialty critical care medicine. However, the national productivity to the subspecialty critical care medicine remains unknown. We therefore intended to reveal the national contribution in the subspecialty critical care medicine journals. MATERIALS AND METHODS Articles published in 20 highly cited journals in subspecialty critical care medicine from 2006 to 2010 were retrieved from Web of Science and PubMed. The number of total articles and randomized, controlled trials, the per capita numbers, total impact factors (IFs), and citations were tabulated to assess the contribution of different countries. RESULTS A total number of 17,667 articles were published in the 20 journals from 2006 to 2010 worldwide. North America, West Europe, and East Asia were the most productive regions. High-income countries published 89.68% of the total articles. The United States published the most number of articles in 2006 to 2010 (6659/17,667, or 37.69%), followed by United Kingdom, Germany, France, and Australia. Besides, the United States also had the most number of randomized, controlled trials (260), the highest total impact factors (27,206.55), and the highest total citations (84,170). When normalized to population size, Australia had the highest number of articles per million population, followed by Netherlands, Switzerland, Austria, and Belgium. CONCLUSION The United States is the most productive country in the subspecialty critical care medicine. When normalized to population size, Australia and some European countries might be more productive.

Metabolomics changes in a rat model of obstructive jaundice: mapping to metabolism of amino acids, carbohydrates and lipids as well as oxidative stress.

The study examined the global metabolic and some biochemical changes in rats with cholestasis induced by bile duct ligation (BDL). Serum samples were collected in male Wistar rats with BDL (n = 8) and sham surgery (n = 8) at day 3 after surgery for metabolomics analysis using a combination of reversed phase chromatography and hydrophilic interaction chromatography (HILIC) and quadrupole-time-of-flight mass spectrometry (Q-TOF MS). The serum levels of malondialdehyde (MDA), total antioxidative capacity (T-AOC), glutathione (GSH) and glutathione disulfide (GSSG), the activities of superoxide dismutase (SOD) and glutathion peroxidase (GSH-Px) were measured to estimate the oxidative stress state. Key changes after BDL included increased levels of l-phenylalanine, l-glutamate, l-tyrosine, kynurenine, l-lactic acid, LysoPCc (14:0), glycine and succinic acid and decreased levels of l-valine, PCb (19:0/0:0), taurine, palmitic acid, l-isoleucine and citric acid metabolism products. And treatment with BDL significantly decreased the levels of GSH, T-AOC as well as SOD, GSH-Px activities, and upregulated MDA levels. The changes could be mapped to metabolism of amino acids and lipids, Krebs cycle and glycolysis, as well as increased oxidative stress and decreased antioxidant capability. Our study indicated that BDL induces major changes in the metabolism of all 3 major energy substances, as well as oxidative stress.

Equal contributions and credit: an emerging trend in the characterization of authorship in major anaesthesia journals during a 10-yr period.

Background The practice of giving certain authors equal credit in original research publications was increasingly common in some specialty. This study aimed to investigate the prevalence and characteristics of designating some authors with equally credited authors (ECAs) in major anaesthesia journals. Methodology/Principal Findings The practice of giving authors equal credit was searched and identified in the three major anaesthesia journals between January 1, 2002 and December 31, 2011. Papers with ECAs had a higher proportion of the total number of articles in 2011 versus published in 2002 (Anesthesiology, 8.8% vs. 0.9%; British Journal of Anaesthesia, 8.8% vs. 0%; Anesthesia & Analgesia, 3.4% vs. 0.3%; totally, 6.4% vs. 0.4%). A significant increasing trend in annual proportion of articles with ECA was found in the three journals. The first two authors listed in the byline had equal credit in most cases. Conclusions/Significance The practice of giving authors equal credit in original research papers is increasingly common in major anaesthesia journals. It may be warranted for the journals to guide the authors how to regard this practice.

Acute PAR2 activation reduces GABAergic inhibition in the spinal dorsal horn.

We investigated the mechanism underlying inhibition of spinal dorsal horn GABAergic neurotransmission to elucidate the role of protease-activated receptor-2 (PAR2). Initially, we confirmed that PAR2 agonist SL-NH(2) applied intrathecally produced mechanical hyperalgesia. Then we performed patch-clamp experiments in substantia gelatinosa neurons of spinal cord slice, and found that spontaneous inhibitory post-synaptic currents (sIPSCs) were significantly decreased in both frequency and amplitude when neurons were incubated with PAR2 agonist SL-NH(2) for a brief time period (2 min). The GABA-mediated currents were significantly reduced, and there was no impact on glycine-mediated currents during this SL-NH(2) treatment. These results suggest that PAR2 activation enhanced the pain response, potentially via inhibition of dorsal horn GABAergic neurotransmission.

Proteinase-activated receptor 1 contributed to up-regulation of enkephalin in keratinocytes of patients with obstructive jaundice.

Background:Skin synthesis of endogenous opioids such as enkephalin is considered to be increased in cholestatic rodents, which may induce antinociception in cholestatic liver disease. No studies have reported yet the expression of skin enkephalin in patients with cholestasis. Methods:Electrical pain threshold, postoperative morphine consumption, and skin enkephalin expression were measured in patients with jaundice (n = 18) and control patients (n = 16). Male Sprague–Dawley rats (n = 52) and human keratinocyte cell line HaCaT were used in vivo and in vitro studies, respectively. Nociceptive thresholds and plasma and skin levels of methionine-enkephalin were compared in protease-activated receptors-1–antagonized and control bile duct–ligated rats. In in vitro study, the effect on thrombin-induced enkephalin expression was examined and the role of extracellular regulated protein kinases 1/2 and p38 was investigated. Results:The authors found that: (1) the electrical pain threshold (mean ± SD) was 1.1 ± 0.1 mA in control patients, whereas it was significantly increased in patients with jaundice (1.7 ± 0.3 mA); 48-h postoperative morphine consumption was approximately 50% higher in the control group than that in the group with jaundice; (2) Skin keratinocytes enkephalin expression was increased in the patients with jaundice; (3) Protease-activated receptors-1 antagonist 1 &mgr;g·kg−1·day−1 treatment to the bile duct–ligated rats significantly reduced plasma levels of methionine-enkephalin, nociceptive thresholds, and keratinocytes enkephalin expression; and (4) protease-activated receptors-1 activation induced enkephalin expression through phosphorylation of extracellular regulated protein kinases 1/2 and p38 in keratinocytes. Conclusion:Protease-activated receptors-1 activation in peripheral keratinocytes may play an important role in the local synthesis of enkephalin during cholestasis.

Sevoflurane has no adverse effects on renal function in cirrhotic patients: a comparison with propofol

Cirrhotic patients are prone to developing renal dysfunction after anaesthesia and surgery. However, no consensus has been reached whether sevoflurane could have adverse effects on renal function in cirrhotic patients. We hypothesised that the use of sevoflurane for general anaesthesia would lead to post‐operative renal dysfunction in cirrhotic patients undergoing liver resection.