BACKGREOUND: The magnitude of neuromuscular blockade is related to plasma concentration of muscle relaxants. This study was designed to compare the maximal depression of twitch height by blood flow occlusion using a tourniquet at various time interval after intravenous administration of muscle relaxants. METHOD: We studied 127 healthy male adult patients who underwent elective surgery under the general anesthesia with propofol infusion and 50% nitrous oxide. The single supramaximal twitch stimulation applied to the ulnar nerve at the wrist at 1 Hz. The twitch response of adductor pollicis muscles were measured by a 2 kg Load Cell strain gauge with a thumb piece modification and recorded by a Gould TA 240 recorder. After occlusion of blood flow by the tourniquet in the upper arm, in which the neuromuscular monitoring was applied on the wrist, we administered the equipotent dose (ED95) of succinylcholine (S group), mivacurium (M group), and vecuronium (V group) intravenously on the contralateral arm respectively. We measured the maximal depression (%) of twitch height after the releasing tourniquet at 30, 60, 90, 120, 150, and 240 second intervals after the injection of each drug. RESULTS: The depression of twitch height was not found from 90 seconds of tourniquet time in the M group, and 120 seconds of tourniquet time in the S group. However, in the V group, the depression of twitch height was maintained to 240 seconds of tourniquet time. CONCLUSIONS: It is suggested that the plasma concentration of mivacurium declined faster than that of succinylcholine, and that of vecuronium decreased slowest among the groups after intravenous administration of equipotent dose (ED95).
Administration, Intravenous ; Adult ; Anesthesia, General ; Arm ; Depression ; Forearm* ; Humans ; Male ; Muscles ; Neuromuscular Agents* ; Neuromuscular Blockade ; Neuromuscular Monitoring ; Nitrous Oxide ; Plasma ; Propofol ; Succinylcholine* ; Thumb ; Tourniquets ; Ulnar Nerve ; Vecuronium Bromide* ; Wrist

Reports of neural and non-neural injury associated with anesthesia have appeared in the medical literature. The majority of these injuries were due to improper patient positioning on the operating table and mostly correlated with the duration of surgery. We observed a case of lumbar disc herniation that was detected after general anesthesia in the traditional supine position. A 34-year-old woman underwent an operation for removal of uterine myoma. She complained of newly developed severe back pain that radiated down the lower right leg. HIVD L4~5 confirmed by lumbar MRI at POD 4th. We felt the cause of HIVD was related to the supine position or preexisting back pain with HIVD was exacerbated during surgery. This is possible to be prevented by evaluating the patient's postural limitation during the visit before anesthesia, padding under lumbar area and a more appropriate position to suit the patient needs for example, Lawn-chair position. The patient was treated with epidural injection of steroid at pain clinic.
Adult ; Anesthesia ; Anesthesia, General* ; Back Pain ; Female ; Humans ; Injections, Epidural ; Leg ; Leiomyoma ; Magnetic Resonance Imaging ; Operating Tables ; Pain Clinics ; Patient Positioning ; Supine Position

Reports of neural and non-neural injury associated with anesthesia have appeared in the medical literature. The majority of these injuries were due to improper patient positioning on the operating table and mostly correlated with the duration of surgery. We observed a case of lumbar disc herniation that was detected after general anesthesia in the traditional supine position. A 34-year-old woman underwent an operation for removal of uterine myoma. She complained of newly developed severe back pain that radiated down the lower right leg. HIVD L4~5 confirmed by lumbar MRI at POD 4th. We felt the cause of HIVD was related to the supine position or preexisting back pain with HIVD was exacerbated during surgery. This is possible to be prevented by evaluating the patient's postural limitation during the visit before anesthesia, padding under lumbar area and a more appropriate position to suit the patient needs for example, Lawn-chair position. The patient was treated with epidural injection of steroid at pain clinic.
Adult ; Anesthesia ; Anesthesia, General* ; Back Pain ; Female ; Humans ; Injections, Epidural ; Leg ; Leiomyoma ; Magnetic Resonance Imaging ; Operating Tables ; Pain Clinics ; Patient Positioning ; Supine Position

BACKGROUND: Meicillin-resistant Staphylococcus aureus(MRSA) is a common cause of nosocomial infections worldwide. Identification of strains by molecular typing facilitates epidemiological studies and improves disease control This study was performed to determine the usefulness of mecA-associated hypervariable region(HVR) polymerase chain reaction (PCR) and random amplified polymorphic DNA(RAPD) analysis in the investigation of a nosocomial MRSA infections. METHODS: Methicillin-resistance was identified by NCCLS disk diffusion method using the oxacillin disk. And PCR was done for detection of mecA gene. Antimicrobial susceptibility test, HVR-PCR and RAPD using 3 primers were performed for epidemiological analysis on isolates of MRSA. RESULTS: During the period from 1997 Dec. to 1998 May, 120 strains of S. aureus were isolated from clinical specimens. Among them, 78 strains were MRSA, and 72 strains were mecA positive. The strains of mecA positive MRSA were classified into four types by antibiogram, six genotypes by HVR-PCR, and 29 groups by RAPD using three primers. The combination of HVR genotypes and RAPD analysis showed 43 different types in 72 mecA positive MRSA isolates The five strains which were repeatedly isolated from the same patients showed the same HVR genotypes and RAPD analysis. CONCLUSIONS: Antibiogram, HVR-PCR, and RAPD could classify MRSA isolates into only 4-6 types, respectively, but combination of these methods could improve the typability. And combination of results of RAPD analysis using three primers were better than that using one primer in epidemiological studies of MRSA because of same reasons. It can be concluded that molecular typing of MRSA using HVR-PCR and RAPD assay is useful in epidemiolgical investigation of nosocomial infections caused by MRSA, because of its simplicity and reproducibility.
Cross Infection ; Diffusion ; Epidemiologic Studies ; Genotype ; Humans ; Methicillin Resistance* ; Methicillin-Resistant Staphylococcus aureus* ; Microbial Sensitivity Tests ; Molecular Typing ; Oxacillin ; Polymerase Chain Reaction ; Staphylococcus