BACKGROUND: Direct puncture by a needle is a risk factor for nerve damage. This study was designed to demonstrate nerve damage caused by a needle using the synchrotron small-angle X-ray scattering (SAXS) technique. METHODS: A 15 mm section of rat (Male Spargue-Dawley, about 250 grams) sciatic nerves were involved in this study. The nerve specimen for the experiment (N = 5) was punctured 5 times by a needle (25 G, 100 beveled) under general anesthesia with enflurane. The needle was placed perpendicular to the nerve and the needle bevel was placed parallel to the nerve. The SAXS patterns of the punctured nerves, extracted about 15 min prior to the experiment, were acquired after 1 week. The SAXS patterns of a normal sciatic nerve (N = 5), extracted about 15 min prior to the experiment, were measured in order to provide a comparison. Experiments were carried out at 4C1 beamline at Pohang Accelerator Laboratory in Korea. Incoming X-rays were monochromatized at 11 keV using a double multilayer (WB4C) monochromator; the beam size was around 0.5 (V) x 0.8 (H) mm2. The exposure time was 60 sec, and 8 to 12 images were acquired per sample with a 0.5 mm interval. RESULTS: In the punctured group, the periodic peaks of myelin sheath and collagen fiber were not changed. However, the periodic peaks of interfibrillar distance of collagen were greatly changed. CONCLUSIONS: Direct needle-nerve impalement did not cause damages in myelin sheath and collagen fibers when the needle was placed perpendicular and the needle bevel paralleled to the nerve fiber. This result can imply that the needle slipped into the interfibrillar packing of collagen fibrils.
Anesthesia, General ; Animals ; Collagen ; Enflurane ; Gyeongsangbuk-do ; Korea ; Myelin Sheath ; Needles* ; Nerve Fibers ; Peripheral Nerve Injuries* ; Punctures ; Rats* ; Risk Factors ; Sciatic Nerve* ; Synchrotrons*

PURPOSE: Takotsubo cardiomyopathy is a relatively uncommon type of stress-induced cardiomyopathy characterized by transient left ventricular regional wall motion abnormalities. Emotional and physical stresses play a key role in this type of cardiomyopathy in postmenopausal women. The current hypothesis is that the syndrome represents a form of catecholamine surge due to stress or epinephrine-mediated acute myocardial stunning. METHODS: A 44-year-old woman had suffered premature ventricular contraction following a cardiogenic shock during a breast augmentation surgery under enflurane anesthesia and tumescent solution infiltration. She was treated with cardiopulmonary resuscitation at a local clinic. Then she was brought to the Emergency Department of the authors' hospital. RESULTS: The woman's echocardiogram showed an ejection fraction of 20~25% with associated basal hyperkinesis and left ventricular apical ballooning. The patient was admitted to the ICU and required inotropic support for two weeks. The patient's condition dramatically improved, and her ejection fraction returned to 70%. CONCLUSION: It is believed that there were multiple triggering factors of the onset of Takotsubo cardiomyopathy in the woman's social and family history, including infiltration of a large volume of the tumescent solution and VPCs induced by enflurane anesthesia without premedication. The importance of careful history-taking, careful pre-operative consultation on psychological suffering especially for breast surgery, premedication before surgery, patient reassurance, and post-operative psychosocial and emotional assistance was again seen in this case.
Adult ; Anesthesia ; Breast ; Cardiomyopathies ; Cardiopulmonary Resuscitation ; Emergencies ; Enflurane ; Female ; Humans ; Hyperkinesis ; Premedication ; Shock, Cardiogenic ; Stress, Psychological ; Takotsubo Cardiomyopathy ; Ventricular Premature Complexes

BACKGROUND: Pregabalin is an anticonvulsant and analgesic agent that interacts selectively with the voltage-sensitive-Ca(2+)-channel alpha-2-delta subunit. The aim of this study was to evaluate whether the analgesic action of intrathecal (IT) pregabalin is associated with KATP channels in the rat formalin test. METHODS: IT PE-10 catheters were implanted in male Sprague-Dawley rats (250-300 g) under inhalation anesthesia using enflurane. Nociceptive behavior was defined as the number of hind paw flinches during 60 min after formalin injection. Ten min before formalin injection, IT drug treatments were divided into 3 groups: normal saline (NS) 20 microl (CON group); pregabalin 0.3, 1, 3 and 10 microg in NS 10 microl (PGB group); glibenclamide 100 microg in DMSO 5 microl with pregabalin 0.3, 1, 3 and 10 microg in NS 5 microl (GBC group). All the drugs were flushed with NS 10 microl. Immunohistochemistry for the KATP channel was done with a different set of rats divided into naive, NS and PGB groups. RESULTS: IT pregabalin dose-dependently decreased the flinching number only in phase 2 of formalin test. The log dose response curve of the GBC group shifted to the right with respect to that of the PGB group. Immunohistochemistry for the KATP channel expression on the spinal cord dorsal horn showed no difference among the groups 1 hr after the formalin test. CONCLUSIONS: The antinociceptive effect of pregabalin in the rat formalin test was associated with the activation of the KATP channel. However, pregabalin did not induce KATP channel expression in the spinal cord dorsal horn.
Anesthesia, Inhalation ; Animals ; Catheters ; Dimethyl Sulfoxide ; Enflurane ; Formaldehyde ; gamma-Aminobutyric Acid ; Glyburide ; Horns ; Humans ; Immunohistochemistry ; KATP Channels ; Male ; Pain Measurement ; Prostaglandins B ; Rats ; Rats, Sprague-Dawley ; Spinal Cord ; Thienamycins ; Pregabalin

BACKGROUND: The use of a tourniquet can produce pain and increase in blood pressure. It is known that fentanyl reduces central sensitization, however its effect on blood pressure increase due to tourniquet is unknown. So we investigated the effect of fentanyl on tourniquet-induced changes of mean arterial blood pressure (MBP), heart rate (HR), and cardiac index (CI). METHODS: ASA physical status I and II, who were scheduled for knee arthroscopic surgery using a tourniquet, were assigned into control (n = 30) and fentanyl group (n = 30). Anesthesia was maintained with enflurane, N2O and O2. Fentanyl was injected 1.5 ug/kg at 10 min before inflation of the tourniquet in the fentanyl group. Changes of the MBP, HR, CI were measured before and 10, 20, 30, 40, 50, 60 min after inflation of the tourniquet. RESULTS: There were no differences in the baseline values. MBP was increased at 40, 50, 60 min in the control group. At 60 min, MBP was lower in the fentanyl than the control group. HR was decreased at 10 min in the fentanyl group. CI was decreased in all groups after tourniquet inflation. At 60 min, CI was more decreased in the control than the fentanyl group. CONCLUSIONS: Fentanyl injection prior to tourniquet inflation can attenuate the tourniquet induced hemodynamic changes in the knee arthroscopic surgery patients.
Anesthesia ; Arterial Pressure ; Arthroscopy ; Blood Pressure ; Central Nervous System Sensitization ; Enflurane ; Fentanyl ; Heart Rate ; Hemodynamics ; Humans ; Inflation, Economic ; Knee ; Thigh ; Tourniquets

BACKGROUNDThe mechanisms of action for volatile anesthetics remain unknown for centuries partly owing to the insufficient or ineffective research models. We designed this study to develop three strains derived from a wild-type Drosophila melanogaster with different sensitivities to volatile anesthetics, which may ultimately facilitate molecular and genetic studies of the mechanism involved.

METHODSMedian effective doses (ED(50)) of sevoflurane in seven-day-old virgin female and male wild-type Drosophila melanogaster were determined. The sensitive males and females of percentile 6 - 10 were cultured for breeding sensitive offspring (S(1)). So did median ones of percentile 48 - 52 for breeding median offspring (M(1)), resistant ones of percentile 91 - 95 for breeding resistant offspring (R(1)). Process was repeated through 31 generations, in the 37th generation, S(37), M(37) and R(37) were used to determine ED(50) for enflurane, isoflurane, sevoflurane, desflurane, halothane, methoxyflurane, chloroform and trichloroethylene, then ED(50) values were correlated with minimum alveolar concentration (MAC) values in human.

RESULTSFrom a wild-type Drosophila melanogaster we were able to breed three strains with high, median and low sevoflurane requirements. The ratio of sevoflurane requirements of three strains were 1.20:1.00:0.53 for females and 1.22:1.00:0.72 for males. Strains sensitive, median and resistant to sevoflurane were also sensitive, median and resistant to other volatile anesthetics. For eight anesthetics, ED(50) values in three strains correlated directly with MAC values in human.

CONCLUSIONSThree Drosophila melanogaster strains with high, median and low sensitivity to volatile anesthetics, but with same hereditary background were developed. The ED(50) are directly correlated with MAC in human for eight volatile anesthetics.

Anesthetics, Inhalation ; pharmacology ; Animals ; Chloroform ; pharmacology ; Drosophila melanogaster ; drug effects ; growth & development ; Enflurane ; pharmacology ; Female ; Halothane ; pharmacology ; Isoflurane ; analogs & derivatives ; pharmacology ; Male ; Methoxyflurane ; pharmacology ; Methyl Ethers ; pharmacology ; Trichloroethylene ; pharmacology

BACKGROUND: This study evaluated the effects of remifentanil on hemodynamic changes in endotracheal intubation during rapid sequence induction using thiopental or propofol and succinylcholine. METHODS: One hundred and twenty patients were divided into 4 groups (30 patients in each group).Anesthesia was induced with propofol 2 mg/kg or thiopental 5 mg/kg and succinylcholine 1 mg/kg followed by remifetanil 0.5microgram/kg (group PR), remifentanil 1microgram/kg (group TR) or normal saline as control (group PC, group TC).An endotracheal intubation was performed 90 s later, and vecuronium 0.08 mg/kg was given for neuromuscular block.Anesthesia was maintained using 1-3 vol% enflurane with 2 L/min N2O and 2 L/min O2.Arterial blood pressure (ABP) and heart rate (HR) were recorded before induction, just before intubation, and at 1 min intervals for 5 min after intubation.The incidence of hypertension, hypotension, tachycardia, and bradycardia were recorded. RESULTS: ABP in group PR was lower than in group TR, but HR was not different.The incidence of hypotension in group PR was higher than group TR or group PC.ABP in groups using remifentanil was lower than in control groups.The incidence of hypertension and tachycardia in groups using remifentanil were lower than control groups. CONCLUSIONS: During administration of propofol or thiopental and succinylcholine, remifentanil as a bolus for rapid sequence induction attenuated cardiovascular responses to endotracheal intubation effectively, but with a higher incidence of hypotension following propofol.
Blood Pressure ; Bradycardia ; Enflurane ; Heart Rate ; Hemodynamics ; Humans ; Hypertension ; Hypotension ; Incidence ; Intubation ; Intubation, Intratracheal ; Piperidines ; Propofol ; Succinylcholine ; Tachycardia ; Thiopental ; Vecuronium Bromide

BACKGROUND: Various aspects of immunological homeostasis are affected by anesthesia and surgery, including the function of immunocompetent cells and the modulation of stress responses. To evaluate immunologic changes that occurred following propofol and enflurane anesthesia, we evaluated the proliferative responsiveness of peripheral blood mononuclear cells (PBMC) in patients undergoing laparoscopic gynecologic surgery. METHODS: PBMC were isolated from patients prior to anesthesia and on the first postoperative day (n = 10). The proliferative response was then evaluated based on the level of 5-bromo-2-deoxyunridine (BrdU) incorporation that occurred during DNA synthesisafter the induction of mitogenic stimulation by treatment with 1 microgram/ml lipopolysaccharides (LPS). To accomplish this, cell proliferation was assayed by enzyme-linked immuno-sorbent assay (ELISA), after which a stimulation index was calculated. RESULTS: Although the calculated stimulation index decreased in response to both propofol and enflurane anesthesia, the stimulation index did not differ significantly between groups. However, following stimulation with LPS, the stimulation index was significantly higher in the enflurane group than in the propofol group (P < 0.05). CONCLUSIONS: Propofol and enflurane anesthesia inhibit the PBMC proliferation. However, the decrease in proliferation that occurred in response to enflurane was attenuated by LPS.
Anesthesia ; Bromodeoxyuridine ; Cell Proliferation ; DNA ; Enflurane ; Homeostasis ; Humans ; Lipopolysaccharides ; Propofol

BACKGROUND: Previous studies suggest that systemic administration of agmatine, endogenous ligand for imidazoline receptors has anti-hypernociceptive effects in experimental animal. However the peripheral effects of agmatine on inflammatory pain have not yet been elucidated. Here we examined the effects of intra-articular injection of agmatine in the induction and maintenance phase of arthritic pain. In addition, we sought to determine the potential contribution of imidazoline and alpha(2)-adrenergic receptors to the antinociceptive effects using clonidine which is mixed alpha(2)-adrenoceptor and imidazoline receptor agonist. METHODS: To induce arthritis in rats, 2% lambda-carrageenan (50microliter, in saline) was injected into the joint of the right hind limb under enflurane anesthesia. Either agmatine (10, 50, 100microgram/40microliter) or clonidine (10, 50, 100microgram/40microliter) was injected into the knee joint cavity immediately before or 4 hr after carrageenan injection. Weight load tests were performed to measure pain-related behavior in freely walking rats. RESULTS: The intraarticular injection of agmatine into the knee joint had no effects in the both phase of induction and maintenance of arthritic pain at any dose tested. However, injection of clonidine reversed arthritic pain, when injected 4 h after carrageenan injection. CONCLUSIONS: In rats, agmatine has no peripheral effect on inflammatory pain and imidazoline receptors in the periphery may not contribute to the anti-inflammatory pain.
Agmatine ; Anesthesia ; Animals ; Arthritis ; Carrageenan ; Clonidine ; Enflurane ; Extremities ; Imidazoline Receptors ; Inflammation ; Injections, Intra-Articular ; Joints ; Knee ; Knee Joint ; Rats ; Walking

BACKGROUND: The use of tourniquet is associated with severe hemodynamic changes, particularly in elderly patients. This study examined the effects of continuously infused remifentanil or nicardipine with esmolol on the attenuation of the hemodynamic changes with enflurane inhalation during total knee arthroplasty in elderly patients. METHODS: Thirty elderly female patients undergoing total knee arthroplasty were enrolled into this randomized, prospective study. Remifentanil (group R) or nicardipine with esmolol (group EN) was infused using a titration method to maintain a mean arterial pressure (MAP) of 90 mmHg to 70 mmHg during tourniquet inflation. In addition, the inhalation of enflurane was adjusted to guarantee a hypnotic state based on entropy. The hemodynamic variables, inhaled concentration of enflurane, recovery time, and postoperative pain characteristics were measured and compared. RESULTS: Following tourniquet inflation, the MAP was increased and maintained in the target since 20 min after that in both group. Following tourniquet deflation the MAP was decreased significantly in both groups and more patients in group R required a vasopressor. Group R inhaled a lower enflurane concentration and showed more rapid recovery than group EN. There were no significant differences in the level of postoperative pain between the two groups. CONCLUSIONS: These results suggest that remifentanil is more likely to be associated with hypotension after tourniquet deflation and require more attention than nicardipine with esmolol.
Aged* ; Arterial Pressure ; Arthroplasty* ; Enflurane ; Entropy ; Female ; Hemodynamics* ; Humans ; Hypotension ; Inflation, Economic ; Inhalation ; Knee* ; Nicardipine* ; Pain, Postoperative ; Prospective Studies ; Tourniquets

BACKGROUND: The use of a tourniquet can produce pain and cause increased blood pressure. Ketorolac is known to have analgesic effects at the peripheral and central levels, however, its effect on the increased blood pressure due to a tourniquet is unknown. Therefore, the effects of ketorolac on the tourniquet-induced changes in the systolic, and diastolic blood pressures (SBP & DBP), as well as the heart rate (HR), were investigated. METHODS: ASA physical status I and II patients, who were scheduled for knee arthroscopic surgery using a tourniquet, were assigned to control (n = 20), K30 (n = 20) and K60 groups (n = 20). Anesthesia was maintained with enflurane, N2O and O2. Either 30 or 60 mg ketorolac was injected 10 min prior to tourniquet inflation in both the K30 and K60 groups. The changes in the SBP, DBP and HR were measured before and 10, 20, 30, 40, 50, and 60 min after tourniquet inflation. RESULTS: There were no differences in the baseline SBP, DBP, and HR values. The SBP was higher than the baseline value at 10, 20, 30, 40, 50, and 60 min in the control and at 30, 40, 50, and 60 min in the K30 groups, but only at 60 min in the K60 group. At 60 min, the SBP was lower in the K60 than the control group. The DBP was higher than the baseline value at 50, and 60 min in the control, but not in the ketorolac groups. CONCLUSIONS: A 60 mg ketorolac injection prior to tourniquet inflation can attenuate the tourniquet induced increase in blood pressure in knee arthroscopic surgery patients.
Anesthesia ; Arthroscopy* ; Blood Pressure* ; Enflurane ; Heart Rate ; Humans ; Inflation, Economic ; Ketorolac* ; Knee* ; Thigh* ; Tourniquets*