Pain management after pneumothorax surgery: intercostal nerve block or thoracic epidural analgesia.

OBJECTIVES: In patients undergoing video-assisted thoracoscopic surgery for pneumothorax, the benefits and risks of single-shot intercostal nerve block as loco-regional analgesia are not well known. We retrospectively compared the effectiveness of intercostal nerve blocks as a viable alternative to thoracic epidural analgesia (TEA) regarding pain control and enhanced recovery. METHODS: A retrospective multicentre analysis with single-centre propensity score matching was performed in patients undergoing video-assisted thoracoscopic surgery for pneumothorax receiving either TEA or intercostal nerve block. The primary outcome was a proportion of pain scores ≥4 (scale 0-10) until postoperative day (POD) 3. Secondary outcomes included variation in pain over time, additional opioid use, length of stay, mobility, complications and recurrence rate. RESULTS: In 218 patients, TEA was compared to intercostal nerve block and showed no difference in the proportion of pain scores ≥4 {14.3% [interquartile range (IQR) 0.0-33.3] vs 11.1% (IQR 0.0-27.3) respectively, P = 0.24}, more frequently needed additional opioids on the day of surgery (18% vs 48%) and first POD (20% vs 42%), had a shorter length of stay (4.0 days [IQR 3.0-7.0] vs 3.0 days [IQR 2.8-4.0]) and were significantly more mobile until POD 3, while having similar recurrences. Intercostal nerve block had higher pain scores early in the course whereas TEA had higher late (rebound) pain scores. CONCLUSIONS: In a multimodal analgesic setting with additional opioids, intercostal nerve block shows comparable moments of unacceptable pain from POD 0-3 compared to TEA and is linked to improved mobility. Results require randomized confirmation.

Inflammatory genes in rat livers from cardiac- and brain death donors.

BACKGROUND: Liver transplantation (LT) is the only life-saving treatment for patients with end-stage liver disease. The increase in patients has prompted the use of not only donation after brain death (DBD) donors but also living donors (LD) and donation after cardiac death (DCD) donors. Donor-type affects early graft function and graft survival as evidenced by an increased risk of developing ischemic type biliary lesions and higher risk of graft loss in DCD as compared with those in DBD grafts. METHODS: Using a rat model, we used quantitative reverse transcription-polymerase chain reaction to examine expression levels of proinflammatory, cytoprotective, and injury genes and determined apoptosis in DCD and DBD livers at different time points after retrieval. RESULTS: After retrieval, early mediators of inflammation MCP-1, HMGB1, and toll-like receptor (TLR 4) were increased in DCD livers, whereas the proinflammatory genes interleukin 6, interleukin 1ß, tumor necrosis factor alpha, P-selectin, and E-selectin were massively upregulated in DBD compared with those in LD livers. HO-1 was increased in both postmortem groups. After cold ischemia, DCD livers showed increased levels of MCP-1, TLR4, and HMGB1, whereas expression of proinflammatory genes in DBD liver remained high. During 12 h of cold storage, expression levels remained stable except Hif-1α and HMGB1. DCD showed higher number of apoptotic cells compared with DBD livers. CONCLUSIONS: Compared with LD, DCD livers showed only mild upregulation of inflammatory markers, but increased levels of MCP-1, HMGB1, and TLR4, and more apoptotic cells. In contrast, DBD livers showed a massive inflammatory response. These differences in tissue injury and inflammatory response might be relevant for the outcome after LT.

A comparison of inflammatory, cytoprotective and injury gene expression profiles in kidneys from brain death and cardiac death donors.

BACKGROUND: The superior long-term survival of kidneys from living donors (LDs) compared with kidneys from donation-after-brain-death (DBD) and donation-after-cardiac-death (DCD) donors is now well established. However, comparative studies on transcriptional changes that occur at organ retrieval and during and after cold ischemia (CI) are sparse. METHODS: Using a rat model, we used qRT-PCR to examine expression levels of inflammatory, cytoprotective, and injury genes at different time points after organ retrieval. Cleaved caspase-3 was used to evaluate early apoptosis in DCD and DBD kidneys. RESULTS: Immediately after retrieval, we found massive up-regulation of proinflammatory genes interleukin-1ß, interleukin-6, tumor necrosis factor-α, monocyte chemotactic protein-1, P-selectin, and E-selectin in DBD compared with LD and DCD kidneys. A significant increase in the expression of injury markers Kim-1, p21, and the cytoprotective gene heme oxygenase-1 accompanied this. Bax was increased in DCD kidneys, and Bcl-2 was decreased in DBD kidneys. After 2 hr of CI in the LD group and 18 hr in the DBD and DCD groups, gene expression levels were similar to those found after retrieval. During 18 hr of cold storage, expression levels of these genes did not change. In DCD and DBD kidneys, early apoptosis increased after CI. DISCUSSION/CONCLUSION: The gene expression profile in DBD kidneys represents an inflammatory and injury response to brain death. In contrast, DCD kidneys show only mild up-regulation of inflammatory and injury genes. These results may imply why delayed graft function in DCD kidneys does not have the deleterious effect it has on DBD kidneys.

Amelioration of renal ischaemia-reperfusion injury by synthetic oligopeptides related to human chorionic gonadotropin.

BACKGROUND: We have previously reported that small synthetic oligopeptides related to human beta-chorionic gonadotropin (beta-hCG) can reduce inflammation. Here we investigated whether such oligopeptides can reduce renal ischaemia-reperfusion injury in the mouse. METHODS: Ten different oligopeptides were administered 1 min before induction of renal ischaemia and 1 min before reperfusion. RESULTS: Survival at 72 h post-reperfusion was significantly higher in mice treated with oligopeptides MTRV, LQG, VLPALPQ or AQGV as compared to placebo-treated mice. Some oligopeptides were more effective than others. AQGV completely prevented mortality and best preserved kidney function. Next, AQGV was tested in a dose-escalating study in a range of 0.3-30 mg/kg. A survival gain was observed with all doses. Improvement of kidney function was observed from 1 mg/kg. Highest survival and best preserved kidney function were observed at 3 and 10 mg/kg. Upon treatment with AQGV, a significantly lower influx of neutrophils was found, apoptosis was decreased, whereas tubular epithelial cell proliferation was significantly increased at 24 h post-reperfusion. Serum levels of TNF-alpha, INF-gamma, IL-6 and IL-10 were significantly decreased at 24 h post-reperfusion. E-selectin mRNA levels in kidneys were significantly decreased at 6 h post-reperfusion. AQGV did not reduce mortality when treatment was started after reperfusion. CONCLUSIONS: This study shows that small oligopeptides related to the primary structure of beta-hCG, especially AQGV, are promising potential drugs for preventing the development of renal ischaemia-reperfusion injury.

Congenital DNA repair deficiency results in protection against renal ischemia reperfusion injury in mice.

Cockayne syndrome and other segmental progerias with inborn defects in DNA repair mechanisms are thought to be due in part to hypersensitivity to endogenous oxidative DNA damage. The accelerated aging-like symptoms of this disorder include dysmyelination within the central nervous system, progressive sensineuronal hearing loss and retinal degeneration. We tested the effects of congenital nucleotide excision DNA repair deficiency on acute oxidative stress sensitivity in vivo. Surprisingly, we found mouse models of Cockayne syndrome less susceptible than wild type animals to surgically induced renal ischemia reperfusion injury, a multifactorial injury mediated in part by oxidative damage. Renal failure-related mortality was significantly reduced in Csb(-/-) mice, kidney function was improved and proliferation was significantly higher in the regenerative phase following ischemic injury. Protection from ischemic damage correlated with improved baseline glucose tolerance and insulin sensitivity and a reduced inflammatory response following injury. Protection was further associated with genetic ablation of a different Cockayne syndrome-associated gene, Csa. Our data provide the first functional in vivo evidence that congenital DNA repair deficiency can induce protection from acute stress in at least one organ. This suggests that while specific types of unrepaired endogenous DNA damage may lead to detrimental effects in certain tissues, they may at the same time elicit beneficial adaptive changes in others and thus contribute to the tissue specificity of disease symptoms.

Donor pre-treatment with tacrolimus reduces transplant vasculopathy.

We tested whether transplant arteriosclerosis can be reduced by pre-treatment of the donor with immunosuppressive agents, using a rat allogeneic aorta transplantation model. Donor rats received no pre-treatment, or tacrolimus, methylprednisolone, rapamycin, or mycofenolate mofetil (MMF) 16 and 2h before explantation of the grafts. Eight weeks after transplantation, aorta allografts were harvested. Percent intima area/intima+media area (I/I+M), inflammatory cells and in situ MMP-2 and -9 activity were determined. In pre-transplantation biopsies, MMP-2 and -9 ratio, and mRNA levels for genes of interest were determined. In pre-transplantation biopsies we found no differences in MMP-2/9 ratio, and Bcl-2, Bax, TGF-beta, HO-1, p21, and HIF-1alpha mRNA expression between the groups. Aorta allografts, pre-treated with tacrolimus, showed significantly lower I/I+M ratio compared to untreated controls (p<0.01). Pre-treatment with methylprednisolone, rapamycin or MMF did not significantly reduce I/I+M ratio. In situ MMP-2/MMP-9 activity was significantly reduced in grafts treated with tacrolimus and rapamycin compared to controls (p<0.05). Immunohistochemistry revealed a high number of CD4+ cells and high CD4/CD8 ratio in grafts pre-treated with tacrolimus. Donor pre-treatment with tacrolimus significantly reduces transplant arteriosclerosis and is associated with reduced in situ MMP-2/MMP-9 activity and increased number of CD4+ cells.