Predicting successful supraclavicular brachial plexus block using pulse oximeter perfusion index.

BACKGROUND: Supraclavicular nerve block is a popular approach for anaesthesia for upper limb surgeries. Conventional methods for evaluation of block success are time consuming and need patient cooperation. The aim of this study was to evaluate whether the perfusion index (PI) can be used to predict and provide a cut-off value for ultrasound-guided supraclavicular nerve block success. METHODS: The study included 77 patients undergoing elective orthopaedic procedures under ultrasound-guided supraclavicular nerve block. After local anaesthetic injection, sensory block success was assessed every 3 min by pinprick, and motor block success was assessed every 5 min by the ability to flex the elbow and the hand against resistance. The PI was recorded at baseline and at 10, 20, and 30 min after anaesthetic injection in both blocked and non-blocked limbs. The PI ratio was calculated as the PI after 10 min divided by the PI at the baseline. Receiver operating characteristic curves were constructed for the accuracy of the PI in detection of block success. RESULTS: The PI was higher in the blocked limb at all time points, and this was paralleled by a higher PI ratio compared with the unblocked limb. Both the PI and the PI ratio at 10 min after injection showed a sensitivity and specificity of 100% for block success at cut-off values of 3.3 and 1.4, respectively. CONCLUSIONS: The PI is a useful tool for evaluation of successful supraclavicular nerve block. A PI ratio of > 1.4 is a good predictor for block success.

The effects of perineural dexmedetomidine on the pharmacodynamic profile of femoral nerve block: a dose-finding randomised, controlled, double-blind study.

This randomised, controlled, double-blind study investigated the effects of different doses of perineural dexmedetomidine on the pharmacodynamic profile of femoral nerve block in patients undergoing arthroscopic knee surgery. Ultrasound-guided femoral nerve block was performed before general anaesthesia using 25 ml of bupivacaine 0.5% combined with normal saline in the control group, and 25 µg, 50 µg or 75 µg of dexmedetomidine in three treatment groups (n = 15 for each group). All patients received a standard general anaesthetic and multimodal postoperative analgesic regimen. The use of the 50 µg and 75 µg dose levels of dexmedetomidine was associated with reduction of the onset time, extension of the duration of block, prolonged time to the first postoperative request for rescue analgesia, and reduced postoperative morphine requirements. The times to first request for postoperative analgesia were mean (SD) 10.8 (1.6) h in the control group and 11.0 (7.1), 21.8 (3.0) and 28.6 (10.0) in the 25 µg, 50 µg and 75 µg treatment groups, respectively. These times were significantly longer in the 50 µg and 75 µg treatment groups compared with the 25 µg (p < 0.0001) and control group (p < 0.0001). The total 24-h postoperative morphine consumption was 7.6 (5.1) mg in the control group, and 6.5 (3.5), 3.9 (3.4), 1.8 (2.6) in the 25 µg, 50 µg and 75 µg treatment groups, respectively. Postoperative morphine consumption was significantly higher in the control group compared with the 50 µg (p = 0.045) and the 75 µg (p = 0.001) treatment groups. The best analgesic profile was achieved at the 75 µg dose, but this was associated with increased risk of hypotension.

DESFLURANE COMPARED TO SEVOFLURANE FOR CIRRHOTIC PATIENTS UNDERGOING MAJOR LIVER RESECTION. A RANDOMIZED CONTROL STUDY.

BACKGROUND: Major liver resection is associated with haemodynamic, hepatic and renal changes as a result of the procedure. AIM: To compare Desflurane (D) versus Sevoflurane (S) on hepatic, renal functions, haemodynamics and perioperative course for cirrhotic patients undergoing major liver resection. PATIENTS AND METHODS: A prospective randomized control study with 50 patients (Child A) (D, n = 25 and S, n = 25). End tidal D or S adjusted with Entropy (40-60). Haemodynamics monitored with invasive blood pressure and trans-oesophageal Doppler (TED). Liver and kidney function tests, blood Glutathione-S-transferase (GST), urinary microalbuminuria (Microalb) were assayed. Extubation time and anaesthetic consumption were recorded. RESULTS: Systemic vascular resistance (SVR) post-resection and stroke volume of D vs S were 835.04 ± 12.02 vs 778.16 ± 11.97 dyn.sec.cm(-5), P < 0.01, and 85.72 ± 2.95 vs 76.16 ± 6.52 ml, P < 0.01 respectively. Doppler corrected flow time (FTc) between groups were comparable (P > 0.05). No difference post-operatively regarding hepatic and renal functions, and urine Microalb (14.76 ± 3.95 vs l4.24 ± 8.65 µg/ml, P = 0.78), but a statistically difference was found with GST (0.046 ± [symbols: see text], vs 0.043 ± [symbols: see text] IU/ml, P < 0.01). Despite a higher D consumption (73 ± 17 vs 64 ± 22 ml, P = 0.102), cost in Egyptian pounds (LE) was lower with D (141.14 ± 32.90 vs 320.60 ± 114.01, LE, P < 0.01). Extubation time and ICU stay with D vS (4.52 ± 2 vs 7.72 ± 2 min, P < 0.01) and (1.40 0.50 vs 1.64 ± 0.48, days P = 0.09) respectively. CONCLUSION: Neither D nor S were clinically superior to the other with respect to liver and kidneys functions, but D was found to preserve better the haemodynamic parameters and enhance recovery at a lower cost.

The anti-inflammatory effects of 1,1 dimethyl-4-phenylpiperazinium (DMPP) compared to dexamethasone in a guinea pig model of ovalbumin induced asthma.

BACKGROUND AND AIM: Inflammatory cells involved in the pathophysiology of asthma express nicotinic receptor. Therefore 1,1 dimethyl(-4-)phenylpiperazinium (DMPP) in two doses were compared to dexamethasone in asthmatic guinea pigs. MATERIALS AND METHODS: Six groups were included; Normal control and five asthmatic (OVA-sensitized and challenged) groups; which were treated for 10 days as follows: two vehicles, dexamethasone (DEXA, 1 mg/kg) and DMPP (0.4 and 0.8 mg/kg) groups. Pulmonary functions and airway hyper-responsiveness were assessed. Leukocytic count, tumor necrosis factor-alpha (TNFα), interleukin-6 (IL-6) and immunoglobulin E (IgE) were measured in both blood and bronchoalveolar lavage fluid (BALF). Histopathological examination of the lung tissues was conducted. RESULTS: Asthmatic untreated animals exhibited significant increase in early and late airway resistance (RxV) and airway hyper-responsiveness, with reduction in tidal volume. Both blood and BALF showed significant increase in total leukocytic count (TLC), eosinophils, lymphocytes, monocytes, TNF-α, IL-6 and IgE with significant decrease in neutrophils. Airway inflammatory cell infiltration and smooth muscle thickness significantly increased. DMPP 0.4 mg/kg significantly decreased late phase RXV, TLC, BALF lymphocytes, TNF-α, smooth muscle thickness and increased neutrophils in BALF over both DEXA and DMPP 0.8 mg/kg. Moreover, DMPP 0.4 mg/kg significantly decreased IL-6 and BALF eosinophils than DMPP 0.8 mg/kg and decreased serum IgE and parenchymal inflammatory infiltration than DEXA. CONCLUSIONS: Low dose DMPP has more anti-inflammatory effect than a high dose in most parameters and sometimes than dexamethasone. Cholinergic anti-inflammatory pathway may therefore represent a potential drug target for allergic asthma. The dose related effect of DMPP and the mechanism underlying this effect require further evaluation.

Impact of omeprazole on bone remodeling in normal and ovariectomized Wistar rats.

BACKGROUND: Several epidemiologic studies have suggested the association between therapy with proton pump inhibitors (PPIs) and bone fractures. AIM: This study aimed at evaluating the effect of omeprazole on bone in normal and ovariectomized Wistar rats and the possible mechanisms involved. MATERIALS AND METHODS: 56 rats were divided into 3 main groups. Normal group; further subdivided into normal control group and two groups which were treated with omeprazole in two doses (20, 40 mg/kg/day i.p). Sham operated group. Ovariectomized group; further subdivided into ovariectomized control group, and two groups which were treated with omeprazole in two doses (20, 40 mg/kg/day i.p). Rats were treated for the last 4 weeks of the total 8 weeks of the experiment. Urine hydroxyproline, serum osteocalcin, TNF-α and IL-6 and bone mineral content were assessed. Omeprazole effects on the endothelial dependent and independent relaxation were determined. RESULTS: Omeprazole in normal and ovariectomized rats produced significant reduction in bone formation, tibia calcium content and serum TNF-α and IL-6. Omeprazole in ovariectomized rats produced a dose dependent decrease in bone resorption. Isolated aortic rings from ovariectomized/omeprazole treated rats exhibited reversal of the endothelial dysfunction that observed with ovariectomized rats. CONCLUSIONS: PPIs might induce both positive and negative effects on bone remodeling. Although these drugs might have the potential to inhibit bone resorption, through suppression of pro-inflammatory cytokines and improvement of endothelial function, yet these effects are counteracted by their inhibitory effects on the gastric proton pump with reduction in calcium absorption and bone formation.

Infection complications and pattern of bacterial resistance in living-donor liver transplantation: a multicenter epidemiologic study in Egypt.

INTRODUCTION: Data on the prevalence and pattern of infection after living-donor liver transplantation (LDLT) are scarce in Egypt. We therefore conducted this study to quantify the incidence, risk factors, and pattern of bacterial resistance post-LDLT in 3 hospitals in Egypt. PATIENTS AND METHODS: We conducted a retrospective, multicenter study of the medical records of 246 patients who underwent LDLT between January 2006 and April 2011 at 3 transplant centers in Egypt. RESULTS: Of 246 patients enrolled in this study, 127 (52%) developed infectious complications after LDLT, with 416 episodes of infection occurring within 3 months of transplantation. Biliary tract infection was the most common, occurring in 169 (40.6%) patients. The rate of infection with Gram-negative bacteria was higher than that of infection with Gram-positive bacteria (310 [74%] vs 87 [21%]; P < .001). Overall, 75% of Gram-negative isolates were multidrug resistant. Significant independent risk factors for infection were portal vein thrombosis (odds ratio, 2.4; P = .037) and biliary complications (odds ratio, 5.4; P < .001). CONCLUSIONS: Our data showed a high-resistance pattern of bacterial infection after LDLT in Egypt. Early biliary complications were an independent risk factor for bacterial infection.