Ömür Mavioğlu

Dilution of rocuronium to 0.5 mg/mL with 0.9% NaCl eliminates the pain during intravenous injection in awake patients.

In a randomized, double-blinded, controlled study, we evaluated the effect of diluting rocuronium 10 mg/mL to 1 or 0.5 mg/mL with 0.9% NaCl on the pain associated with IV administration of rocuronium with small doses given before succinylcholine or nondepolarizing agent administration. One hundred fifty patients undergoing surgical procedures that required general anesthesia were randomized into three groups. Group 1 received rocuronium 10 mg/mL. Groups 2 and 3 received 1 and 0.5 mg/mL of rocuronium, respectively. Patient demographics, pain scores, osmolality, and the pH of the solutions were recorded. Group 1 had the most intense and frequent pain response. Eighty percent of patients in this group reported pain on injection. In Group 2, the incidence and intensity of pain were significantly less when compared with those of Group 1. In this group, 38% of patients reported pain during injection. In Group 3, none of the patients experienced pain on injection. The pH values and osmolalities of study solutions were not significantly different among groups. In conclusion, in awake patients, dilution of rocuronium 10 mg/mL at small doses given before succinylcholine or nondepolarizing agent administration of 0.06 mg/kg to 0.5 mg/mL with 0.9% NaCl is a simple and cost-effective strategy for preventing pain during IV rocuronium injection.

A new method for estimating arterial occlusion pressure in optimizing pneumatic tourniquet inflation pressure.

To reduce pressure-related injuries resulting from pneumatic tourniquet use, the lowest possible inflation pressure is recommended. Arterial occlusion pressure (AOP) is a measure of the cuff pressure required to maintain a bloodless surgical field. However, its determination method is time consuming, requires operator skill, and is therefore seldom used in current practice. An AOP estimation can be made by knowing the pressure transmitted to the underlying soft tissues. We measured upper and lower extremity tissue pressures under the tourniquet cuff at 100, 200, and 300 mm Hg of tourniquet inflation pressures in 30 anesthetized living adult patients. All patients received general anesthesia with neuromuscular relaxation. A Stryker intra-compartmental pressure monitor was used to measure tissue pressures under the tourniquet cuff. In all patients, the soft tissue pressures were consistently lower than the applied tourniquet inflation pressures. Our results revealed tissue padding coefficients for extremities 20 to 75 cm in circumferences. An estimation method of AOP was developed [AOP = (systolic blood pressure + 10)/Tissue padding coefficient]. The new AOP estimation method may be a simple, rapid, and clinically practical alternative to the AOP determination method.

Ischaemic preconditioning attenuates haemodynamic response and lipid peroxidation in lower-extremity surgery with unilateral pneumatic tourniquet application: A clinical pilot study

Introduction: The harmful effects of ischaemia-reperfusion on skeletal muscle during extremity surgery can be diminished by using medications or ischaemic preconditioningMethods: Twenty patients undergoing lower-limb surgery with use of a tourniquet for at least 1 hour were included in the study and randomised into two groups: a control group with only tourniquet application (T group; n =10); and an ischaemic preconditioning plus tourniquet group (IP-T group; n =10). Blood samples were obtained from the femoral vein of the relevant extremity before tourniquet application (baseline), immediately after tourniquet deflation (TD), at 10 minutes after the tourniquet deflation (TD 10min ) in the T group and additionally after ischaemic preconditioning in the IP-T group. Venous blood pH, partial oxygen pressure (P vO2 ), partial carbon dioxide pressure (P vCO2 ), lactate, potassium, sodium and glucose levels were analysed using a blood gas analyser. Plasma thiobarbituric acid reactive substances (TBARS) level, an index of lipid peroxidation and oxidative stress, was measured. Heart rate, noninvasive mean arterial pressure (MAP) and spontaneous breathing rate (SBR) were recorded at baseline, at TD, and TD 1min , TD 5min and TD 10minResults: MAP decreased and SBR increased significantly at TD, TD 1min and TD 5min compared with baseline, and venous blood TBARS level significantly increased at TD and TD 10min compared with baseline in the T group (all P <0.05). No significant changes were observed in the IP-T group. Ischaemic preconditioning caused a rise in P vO2 and a decrease in venous blood pH, P vCO2 , and lactate levels, which was significant compared with baseline ( P <0.05)Conclusion: Ischaemic preconditioning attenuates haemodynamic response and lipid peroxidation during lower-extremity surgery with unilateral tourniquet application

Epidural lornoxicam administration – innocent

We aimed to determine the analgesic efficacy and clinical or histopathological neurotoxicity of epidural single-dose lornoxicam. Caudal epidural catheters were inserted into 28 rabbits, divided into four groups, on day 1. Pain latency and degree of motor and sensory loss for each animal for different concentrations of lornoxicam were determined on day 2. All animals were sacrificed on day 3 and laminectomy was performed. Five-mum thick sections of spinal cord, obtained from two segments caudal and two segments rostral from tip of the catheter, were fixed and were stained and evaluated by light microscopy. Lornoxicam produced dose-dependent analgesia (increase in pain latency), brief, mild and reversible motor and sensory block, and histopathological signs of neurotoxicity. Clinical application of epidural lornoxicam should proceed with caution.

The effects of gender and menopause on serum lidocaine levels in smokers

SummaryIt has been established that human cytochrome P450 (CYP) enzymatic activity is affected by gender, or by hormonal factors such as the menopause in women. Gender differences have a more pronounced effect on cytochrome (CYP) 3A4 isoenzyme activity, whereas cytochrome (CYP) 1A2 isoenzyme activity is mainly induced by chronic smoking. Lidocaine is frequently used in the treatment of hemodynamic changes following laryngoscopy and tracheal intubation during general anesthesia, and is metabolized by CYP3A4 and CYP1A2 isoenzymes in the liver.The aim of this study was investigate the effects of gender and menopause on serum lidocaine levels in smokers under general anesthesia. Six men, six premenopausal women and six postmenopausal women were enrolled in the study and received i.v. lidocaine (1 mg/kg) 1 minute before they underwent general anesthesia. Serum lidocaine concentrations were measured using the EMIT® method at 1, 5, 10, 20, 40 and 60 minutes post-administration. Statistical analyses were performed using the Mann-WhitneyU-test.No statistically significant differences were found regarding the area under curve (AUC(0−60) μg/mL/min), elimination half-life (t1/2 [min]) of lidocaine and in the measured levels of serum lidocaine at any time point between the study groups (p>0.05). These results suggest that gender and menopause may have no significant effect on serum lidocaine levels in smokers.

Effect of hydroxyethyl starch 130/0.4 on ischemia-reperfusion determinants in minor lower extremity surgery with tourniquet application

STUDY OBJECTIVE To investigate the effect of 6% hydroxyethyl starch (HES) (130/0.4) infusion on ischemia-reperfusion determinants in minor lower extremity operations with tourniquet application. DESIGN Prospective, randomized, clinical trial. SETTING University hospital operation room. PATIENTS American Society of Anesthesiologists I and II 40 patients between 18 and 65 years of age who were scheduled to undergo knee arthroscopy and below-knee minor orthopedic surgery. INTERVENTIONS Patients were randomized into 2 groups (normal saline [NS] group and HES group). Unilateral spinal anesthesia with 2-mL 0.5% hyperbaric bupivacaine after 10 mL/kg NS intravenous infusion to NS group and 10 mL/kg 6% HES intravenous infusions to HES group. MAIN OUTCOME MEASURES Blood samples were obtained from antecubital vein for malondialdehyde, xanthine oxidase, and hypoxanthine before tourniquet inflation and after 10 minutes of tourniquet deflation. RESULTS There was no significant difference between groups with respect of hemodynamic data. There were no significant differences between 2 groups in terms of malondialdehyde values before tourniquet inflation and after tourniquet deflation. In the HES group, xanthine oxidase levels after tourniquet deflation were significantly lower than xanthine oxidase levels before tourniquet inflation (P < .05). In the HES group, hypoxanthine levels after tourniquet deflation were similar with the basal levels; however, they were significantly higher than levels obtained before tourniquet inflation in the SF group (P < .05). CONCLUSION HES infusion may be beneficial for reduction of tourniquet-associated ischemia-reperfusion injury; however, further large-scale studies are needed to fully elucidate its mechanism.

Effect of analgesia administration timing on early post-operative period characteristics: a randomized, double-blind, controlled study.

This study investigated the effect of time of analgesia administration in 64 patients undergoing total abdominal hysterectomy. Patients received standard general anaesthesia and were divided randomly into two equal groups. At the time of fascia closure, patients in the intra-operative (Iop) group received 0.5 mg/kg pethidine intravenously. On arrival in the post-anaesthesia care unit, the same dose of pethidine was given to patients in the post-operative (Pop) group. All patients then used a patient-controlled analgesia pump to administer pethidine analgesia as required. Times to extubation, response to verbal stimulation and orientation, post-operative pain scores and analgesic consumption were recorded. Times to extubation and response to verbal stimulation were significantly longer in the Iop group. Pain scores, analgesic consumption and additional analgesic requirements were significantly higher in the Pop group in the first 2 h post-operatively. In conclusion, intra-operative administration of pethidine provided better pain management than post-operative administration.

Comparison of the Haemodynamic Effects of Interscalene Block Combined with General Anaesthesia and Interscalene Block Alone for Shoulder Surgery

Interscalene brachial plexus block (ISB) anaesthesia is widely used with or without general anaesthesia in patients undergoing shoulder surgery, which is generally done with the patient in a sitting position. This position affects haemodynamics, and supplementing ISB with general anaesthesia can exaggerate these haemodynamic changes. This study compared ISB combined with general anaesthesia, with ISB alone, in 29 patients undergoing elective shoulder surgery. Heart rate and oxygen saturation remained stable throughout the study in both groups. Mean arterial pressure was significantly decreased when the patient moved into the sitting position in those given combined anaesthesia, whereas in those given ISB alone mean arterial pressure did not change significantly. Neither pain scores nor patient satisfaction scores differed significantly between the two groups. All of the patients were either satisfied or entirely satisfied with their anaesthesia/analgesia. There were no significant differences in side-effects and no severe complications in either group. We advocate using ISB alone for patients undergoing shoulder surgery, but further larger studies are needed to confirm the present results.

Comparison of Two Different Enteral Nutrition Protocol in Critically Ill Patients

OBJECTIVE In this study, two enteral nutrition protocols with different gastric residual volumes (GRVs) and different monitoring intervals were compared with respect to gastrointestinal intolerance findings in intensive care unit (ICU) patients. METHODS The study was carried out prospectively in 60 patients in the anaesthesiology and reanimation ICU under mechanical ventilation support, who were scheduled to take enteral feeding. Patients were sequentially divided into two groups: Group 1, GRV threshold of 100 mL, and monitoring interval of 4 hours, and Group 2, GRV threshold of 200 mL, monitoring interval of 8 hours. To test the significant difference between the groups, Students t test, chi-square text and Fisher exact test were used. RESULTS In Group 1, 3.3% vomiting, 6.6% diarrhoea was observed; in Group 2, 16.6% vomiting, 10% diarrhoea. In terms of total intolerance (vomiting and/or diarrhoea) of the two groups, the incidence was significantly higher in Group 2 (33.3%) than in Group 1 (10%) (p=0.02). CONCLUSION According to the results of the study, a lower gastrointestinal intolerance rate was detected in the GRV threshold 100 mL, monitoring interval for 4 hours protocol (Group 1) than in GRV threshold 200 mL, monitoring interval for 8 hours protocol (Group 2); Group 1 may be preferred renovation.

The Effect of Midazolam Pre-Medication on Rocuronium-Induced Neuromuscular Blockade

We investigated the effect of midazolam pre-medication on rocuronium-induced neuromuscular blockade during sevoflurane anaesthesia. Twenty-two patients scheduled for elective surgery were randomly divided to receive either no pre-medication (control group) or pre-medication with 0.1 mg/kg midazolam intramuscularly (midazolam group). Anaesthesia was induced with fentanyl and propofol, and maintained with sevoflurane and nitrous oxide in oxygen. Neuromuscular responses were monitored using acceleromyography. The onset and clinical duration of action, time to recovery of first twitch of train-of-four (TOF) response to 75% of control, recovery index and time for TOF recovery to 25% and 50% were recorded. Patient-related data were similar in both groups. The parameters recorded were not significantly different between the groups. Midazolam pre-medication does not influence the time-course of action of rocuronium during sevoflurane anaesthesia.