Influence of dexmedetomidine and lidocaine on perioperative opioid consumption in laparoscopic intestine resection: a randomized controlled clinical trial.

OBJECTIVE: The consumption of opioid analgesics could be reduced by the use of analgesics with different mechanisms of action. We investigated whether additional treatment with dexmedetomidine or lidocaine could reduce opioid consumption. METHODS: We randomized 59 study participants into three groups and examined: (i) fentanyl consumption, (ii) consumption of piritramide, and (iii) cognitive function and neuropathic pain. The control group received continuous propofol infusion and fentanyl boluses. Continuous intravenous infusion of dexmedetomidine (0.5 µg/kg/h) was administered to the dexmedetomidine group and lidocaine (1.5 mg/kg/h) was administered to the lidocaine group. RESULTS: No reduction in fentanyl consumption was observed among the groups. However, we noted a significantly lower consumption of piritramide on the first and second postoperative day in the lidocaine group. Total consumption of piritramide was significantly lower in the lidocaine group compared with the control group. CONCLUSIONS: Lidocaine and dexmedetomidine reduced intraoperative propofol consumption, while lidocaine reduced postoperative piritramide consumption. Clinical trial registration: NCT02616523.

Dexamethasone does not diminish sugammadex reversal of neuromuscular block - clinical study in surgical patients undergoing general anesthesia.

BACKGROUND: Sugammadex reverses neuromuscular block (NMB) through binding aminosteroid neuromuscular blocking agents. Although sugammadex appears to be highly selective, it can interact with other drugs, like corticosteroids. A prospective single-blinded randomized clinical trial was designed to explore the significance of interactions between dexamethasone and sugammadex. METHODS: Sixty-five patients who were anesthetized for elective abdominal or urological surgery were included. NMB was assessed using train-of-four stimulation (TOF), with rocuronium used to maintain the desired NMB depth. NMB reversal at the end of anaesthesia was achieved using sugammadex. According to their received antiemetics, the patients were randomized to either the granisetron or dexamethasone group. Blood samples were taken before and after NMB reversal, for plasma dexamethasone and rocuronium determination. Primary endpoint was time from sugammadex administration to NMB reversal. Secondary endpoints included the ratios of the dexamethasone and rocuronium concentrations after NMB reversal versus before sugammadex administration. RESULTS: There were no differences for time to NMB reversal between the control (mean 121 ± 61 s) and the dexamethasone group (mean 125 ± 57 s; P = 0.760). Time to NMB reversal to a TOF ratio ≥0.9 was significantly longer in patients with lower TOF prior to sugammadex administration (Beta = -0.268; P = 0.038). The ratio between the rocuronium concentrations after NMB reversal versus before sugammadex administration was significantly affected by sugammadex dose (Beta = -0.375; P = 0.004), as was rocuronium dose per hour of operation (Beta = -0.366; p = 0.007), while it was not affected by NMB depth before administration of sugammadex (Beta = -0.089; p = 0.483) and dexamethasone (Beta = -0.186; p = 0.131). There was significant drop in plasma dexamethasone after sugammadex administration and NMB reversal (p < 0.001). CONCLUSIONS: Administration of dexamethasone to anesthetized patients did not delay NMB reversal by sugammadex. TRIAL REGISTRATION: The trial was retrospectively registered with The Australian New Zealand Clinical Trials Registry (ANZCTR) on February 28th 2012 (enrollment of the first patient on February 2nd 2012) and was given a trial ID number ACTRN12612000245897 and universal trial number U1111-1128-5104.

Balance of pro- and anti-inflammatory cytokines in liver surgery.

Inflammatory response in surgery is associated with the release of cytokines. Many cytokines are produced by macrophages; therefore surgical injuries to the liver may have great influence on the release of cytokines. Ischemia creates tissue injury and may contribute to the cytokine release. A balanced ratio of pro- and anti-inflammatory cytokines is important for appropriate immune response; excessive inflammation or hypo-responsiveness can lead to post-operative complications. To determine the magnitude of the cytokine response caused by liver surgery and to evaluate the balance of pro- and anti-inflammatory cytokines released during the operation, we measured levels of tumor necrosis factor-alpha (TNFalpha), interleukin (IL)-1beta, IL-6 and IL-10 in 19 patients undergoing liver resection. The results showed a continuous rise of IL-6 and a transient elevation of IL-10. Levels of TNFalpha remained low; IL-1beta was not detected at any sampling time. We conclude that liver surgery induces cytokine response characterized predominantly by an early appearance of IL-6 and IL-10, the elevation of IL-6 may be mainly caused by splanchnic ischemia. The IL-6/IL-10 ratio could possibly reflect the balance of pro- and anti-inflammatory cytokines in liver surgery better than the TNFalpha/IL-10 ratio, which can well represent inflammatory status in sepsis.

Neopterin--an early marker of surgical stress and hypoxic reperfusion damage during liver surgery.

Neopterin is elevated in infections, autoimmune diseases and post-transplant. Recently neopterin elevation was linked to stress response and malignancy. To determine early changes of serum neopterin caused by surgical stress and to investigate their association with other inflammatory markers and with malignancy, we measured neopterin, C-reactive protein (CRP) and procalcitonin (PCT) levels at four predefined time-points within 24 hours in 27 patients admitted for liver resection. Our results show that neopterin increased during operation and the increase was not related to preoperative neopterin levels. On the first day after surgery neopterin level was not significantly different from postoperative levels. In patients with malignant disease neopterin concentration before operation was higher than in patients with non-malignant disease, however, the increase in neopterin concentration during operation was not different between both patient groups. During surgery CRP and PCT did not increase significantly. On the first postoperative day CRP and PCT were elevated and their levels correlated with neopterin (Pearson's correlation coefficient r=0.51 and r=0.76, respectively). We conclude that neopterin elevation during liver resection contributes major part to the increased levels observed on the first postoperative day. Perioperative neopterin release can/may be related to stress response and hypoxia produced during operation. Using this marker, hypoxic reperfusion damage could be detected earlier and more accurately.