PURPOSE: Organophosphates, commonly used in agricultural pesticides, pose high risks and incidences of poisoning. In the present study, we investigated the relative risk and clinical severity, including laboratory results, of non-oral route poisoning (NORP) patients, compared to oral route poisoning (ORP) patients. MATERIALS AND METHODS: A single institutional toxicology database registry was utilized to gain information on clinical laboratory results on organophosphate poisoning patients who visited the emergency department (ED) between January 2000 and October 2016. Clinical outcomes, such as mortality and complication rates, were compared using 1:2 propensity score matching in the total cohort. RESULTS: Among a total of 273 patients in our study, 34 experienced NORP. After 1:2 propensity score matching, rates of respiratory complications and mortality were higher in the ORP group than in the NORP group. However, there was no difference in hospitalization time and time spent in the intensive care unit between the two groups. Compared with ORP patients after matching, the relative risk of mortality in NORP patients was 0.34, and the risk of respiratory distress was 0.47. The mean level of pseudocholinesterase was significantly higher in the NORP group than in the ORP group, while recovery rates were similar between the two groups. CONCLUSION: Although the majority of NORP patients were admitted to the ED with unintentional poisoning and the relative risk of NORP was lower than that for ORP, we concluded that NORP is as critical as ORP. Considerable medical observation and intensive therapeutic approaches are also needed for NORP patients.
Cholinesterases ; Cohort Studies ; Emergency Service, Hospital ; Hospitalization ; Humans ; Incidence ; Intensive Care Units ; Mortality ; Organophosphate Poisoning* ; Organophosphates ; Pesticides ; Poisoning* ; Propensity Score ; Pseudocholinesterase ; Toxicology

No abstract available.
Humans ; Paralysis* ; Pseudocholinesterase* ; Succinylcholine*

PURPOSE: Measurement of pseudocholinesterase (PChE) is a simple test for evaluation of the severity of intoxication with organophosphate and carbamate insecticides, because they inhibit PChE; however, as demonstrated in several studies, PChE does not reflect severity and mortality. The basal level of PChE in patients who attempt suicide with insecticides could be low, because they are exposed to insecticides for a long period of time, as they are engaged in agriculture. This is part of the reason that PChE level does not reflect severity. No research on the basal level of PChE in the normal population in South Korea has been conducted. The authors of this study investigated the characteristics of residents of Jeju, Korea who have a low level of PChE. METHODS: Residents of Jeju over 60 years of age were randomly enrolled. Level of PChE, demographic data, medical history, and occupation were investigated. Groups (higher level vs lower level) were divided on the basis of the median value of PChE. Mann-Whitney test, Pearson chi square, or Fisher's exact test was used for comparison between the two groups. Logistic regression was used for evaluation of factors having an effect on low level of PChE. RESULTS: Of a total of 353 residents, 28(7.9%) residents were engaged in agriculture, and had recently used insecticide. Sixteen (4.5%) residents had lower PChE levels out of normal range (5,400~13,200 U/L), and the lower group included 177 residents. Age of residents in the lower group was older, and the level of high-density lipoprotein (HDL) was lower, compared with those of the higher group. Older age and lower HDL levels indicated a risk of lower PChE in univariate logistic regression, however, the only risk factor in multivariate logistic regression was age. CONCLUSION: Many potential causes of lower PChE must be considered; genetics, chronic disease, hepatic failure, liver cirrhosis, malnutrition, tumor, infection, and pregnancy. In this study, the only risk factor was age. Future investigation of genetic factors and other risk factors contributing to lower PChE level in residents under 60 years of age will be necessary.
Agriculture ; Carbamates ; Cholinesterases ; Chronic Disease ; Humans ; Insecticides ; Korea ; Lipoproteins ; Liver Cirrhosis ; Liver Failure ; Logistic Models ; Malnutrition ; Occupations ; Organophosphates ; Pregnancy ; Pseudocholinesterase ; Reference Values ; Republic of Korea ; Risk Factors ; Suicide

Amitraz is acaricidal and insecticidal pesticide used worldwide to control ticks and mites in plants and animals. Amitraz poisoning is characterized by clinical toxidrome such as central nervous system, respiratory depression, bradycardia, hypotension, hypothermia, and hyperglycemia. Toxic mechanism of amitraz is mainly alpha2-agonistic function and poisonings may occur by any route. Such clinical symptoms and signs of acute amitraz poisoning were possible to be thought as a toxidrome of acute organophosphate poisoning. We reported a 68-year-old woman that initially was misdiagnosed as acute organophosphate poisoning on the ground of symptoms and signs of mental change, respiratory depression, bradycardia, and hypotension. However, the serum level of pseudocholinesterase level at emergency room admission was within normal level and a vacant bottle of amitraz pesticide was founded around the yard of the patient. The patient was totally recovered from acute amitraz poisoning 2 days later after mechanical ventilation and conservative cares including atropine injection.
Animals ; Atropine ; Bradycardia ; Central Nervous System ; Emergencies ; Female ; Humans ; Hyperglycemia ; Hypotension ; Hypothermia ; Mites ; Organophosphate Poisoning ; Organophosphates ; Pseudocholinesterase ; Respiration, Artificial ; Respiratory Insufficiency ; Ticks ; Toluidines

PURPOSE: Organophosphate insecticide poisoning is common in Korea, but there is no definitive guideline for determining the severity of the poisoning and the predictive factors. Therefore, we evaluated the organophosphate poisoned patients and we divided them into two groups, the survivors and the dead, and the results might be useful for treating organophosphate poisoning patients. METHODS: We performed a retrospective analysis of 68 organophosphate poisoned patients who visited the Chosun University Hospital Emergency Medical Center during a 24-month period from January, 2007 to December, 2008. We made a work sheet of the patients' characteristics and the collected data was analyzed and we compared this data between the survivor group and the dead patient group. RESULTS: There were significant differences between the survivor group and the dead patient group for the mean age, the alcohol intake state and the typically expressed signs. The dead patients had lower blood pressure, tachycardia and a lower Glasgo Coma Score (GCS) score than the survivor group. On the arterial blood gas analysis, the dead patients had more severe acidemia and they had lower saturations. Increased serum amylase levels were found in the dead patients. The survivors' initial and follow up serum pseudocholinesterase activity (after 6~8 days) was significantly higher than that of the dead group. The total amount of atropine injected to patient was less in the survivors than that in the dead patients. CONCLUSION: Old age and expressing the typical intoxication signs, a lower GCS score and blood pressure, showing acidosis on the gas analysis and low serum cholinesterase activity may be useful as poor prognostic indicators for patients with organophosphate poisoning. We suggest that physicians must pay careful attention to the signs and prognostic factors of organophosphate insecticide poisoned patients.
Acidosis ; Amylases ; Atropine ; Blood Gas Analysis ; Blood Pressure ; Cholinesterases ; Coma ; Emergencies ; Follow-Up Studies ; Humans ; Korea ; Organophosphate Poisoning ; Pseudocholinesterase ; Retrospective Studies ; Survivors ; Tachycardia

BACKGROUND: Burned patients sometimes require rapid onset of neuromuscular paralysis to secure the airway in full stomach patients or to treat laryngospasm. Because of poor lung function and hypermetabolic state, they desaturate quite rapidly. Burned patients are usually resistant to the effects of nondepolarizing relaxants. Mivacurium can be potentially a good alternative for rapid onset of paralysis, since it is metabolized by plasma cholinesterase, an enzyme often decreased in subject with major burns. This prospective study was conducted to define the neuromuscular pharmacodynamic profile of a single bolus dose of mivacurium in adult patients with major burns. METHODS: Adults (M/F = 22/8), aged 44.0 +/- 10.2 years, with total body surface area (TBSA) burn of 35.0 +/- 12.5% were studied at 39.8 +/- 28.9 post burn days. Age and sex matched 30 non-burned patients served as controls. Anesthesia was consisted of propofol and fentanyl infusion with nitrous oxide and oxygen. Mivacurium 0.2 mg/kg was administered as a bolus. Using TOF Watch, neuromuscular block was monitored with T1 response after the initial tetanic stimulation to recruit all muscle fibers. Onset time was defined as the interval from the beginning of drug administration to maximal twitch suppression. Intubation was attempted at 1 minute after the drug administration to simulate the rapid sequence induction with recording of either failure or success of intubation. By allowing spontaneous recovery without reversal drug, recovery profiles of neuromuscular paralysis were also measured. RESULTS: Patients demographics were similar in both groups except for the burn. Onset times and all recovery profiles were significantly prolonged in the burned versus non-burned groups. Attempts at intubation at 1 minute after the drug administration were successful with difficulty in approximately 70% of patients in both groups. CONCLUSIONS: Mivacurium 0.2 mg/kg demonstrated the conflicting dual responses in the burned patients. The prolonged onset time suggests resistance to neuromuscular effects. The prolonged recovery suggests increased sensitivity. This can be partially explained by the acetylcholine receptor proliferation and decreased level of plasma pseudocholinesterase. In view of the prolonged onset time of almost two minutes for maximal paralysis, mivacurium does not appear to be a good drug for rapid onset of paralysis in burns.
Acetylcholine ; Adult ; Anesthesia ; Body Surface Area ; Burns* ; Cholinesterases ; Demography ; Fentanyl ; Humans ; Intubation ; Laryngismus ; Lung ; Neuromuscular Agents ; Neuromuscular Blockade ; Nitrous Oxide ; Oxygen ; Paralysis ; Plasma ; Propofol ; Prospective Studies ; Pseudocholinesterase ; Stomach

BACKGROUND: A reproducible animal model of liver cirrhosis by administering multiple doses of carbon tetrachloride (CCl4) is highly desirable for appropriate metabolic and therapeutic studies. The current study was undertaken to evaluate the neuromuscular blockade of mivacurium in CCl4 induced liver cirrhosis in rabbits. METHODS: Cirrhosis was induced in rabbits by CCl4 treatment for 11 weeks. Rabbits were randomly assigned to two groups; control group: corn oil 0.5 ml/kg/2 days IM for 11 weeks; study group: CCl4 0.5 ml/kg/2 days mixed 1:1 with corn oil IM for 11 weeks. In the first study, the dose-response relations of mivacurium were studied in twenty rabbits during thiopental anesthesia. They received mivacurium 10, 20, and 30 microgram/kg in control group, and mivacurium 20, 30, and 40 microgram/kg in study group, respectively. In the second study, time course of mivacurium 0.18 mg/kg in twenty rabbits was evaluated in each groups. Three fragments of each liver lobe at the end of the experimental period were performed for the histological examination. RESULTS: Eleven-weeks CCL4 treatment resulted in liver cirrhosis, decreased pseudocholinesterase to 1/6 of control level, and increased AST and ALT compared with controls. In the first study, There were significant differences between two groups. In the second study, There were significant differences between two groups. CONCLUSIONS: It is suggested that mivacurium should be used with caution in patients with hepatic insufficiency and that, in such patients, monitoring of neuromuscular function is desirable.
Anesthesia ; Carbon Tetrachloride* ; Carbon* ; Corn Oil ; Fibrosis ; Hepatic Insufficiency ; Humans ; Liver Cirrhosis* ; Liver* ; Models, Animal ; Neuromuscular Blockade ; Pseudocholinesterase ; Rabbits* ; Thiopental ; Time and Motion Studies

BACKGROUND: Mivacurium is a nondepolarizing neuromuscular blocking agent hydrolyzed by pseudocholinesterase. Anticholinesterase used in the reversal of mivacurium-induced muscle relaxation may also inhibit plasma pseudocholinesterase, and delay hydrolysis of mivacurium. In this study, the effects of edrophonium and/or bovine pseudocholinesterase (BpChE) in the reversal of mivacurium were investigated with the rat phrenic nerve-diaphragm preparation. METHODS: Fifty Sprague-Dawley rats (150 - 200 g) were randomly allocated into 10 groups based on the dosage of edrophonium and BpChE. Each animal was anesthetized with thiopental sodium (40 mg/kg I.P.). The phrenic nerve-diaphragm was dissected and mounted in a bath containing an oxygenated Krebs' solution at 32degreesC. The phrenic nerve was stimulated at supramaximal intensity and the single twitch responses and train of four (TOF) ratio were measured. After stabilization of the twitch responses, mivacurium (1ng/ml) was administered incrementally to obtain more than 95% twitch inhibition. Reversal of the mivacurium-induced block by edrophonium (0.01, 0.1, 1, or 10ng/ml) and/or BpChE (0.1 u, or 1.0 u/ml) were tested. A single twitch height more than 75% of the baseline value was considered an adequate reversal. RESULTS: Mivacurium-induced paralysis was recovered more effectively by BpChE 1.0 u/ml than the other groups. Edrophonium improved a single twitch in a dose dependent manner. CONCLUSIONS: Mivacurium-induced paralysis can be more effectively reversed by BpChE than edrophonium. Inhibition of pseudocholinesterase was not observed by increasing the dose of edrophonium.
Animals ; Baths ; Edrophonium* ; Hydrolysis ; Muscle Relaxation ; Neuromuscular Blockade ; Oxygen ; Paralysis* ; Phrenic Nerve ; Plasma ; Pseudocholinesterase* ; Rats ; Rats, Sprague-Dawley ; Thiopental

BACKGROUND: Myasthenia gravis is an autoimmune neuromuscular disorder that shows increased sensitivity to nondepolarizing muscle relaxants. Mivacurium chloride is a short acting nondepolarizing neuromuscular blocker and a benzylisoquinolin diester that is hydrolized rapidly to inactive metabolites by plasma pseudocholinesterase. The onset and duration of mivacurium in patients undergoing a thymectomy with myasthenia gravis was studied. METHODS: Fifteen patients undergoing a thymectomy for myasthenia gravis and fifteen patients of ASA class I, II without liver, kidney or neuromuscular disease undergoing orthopedic surgical procedures were included in this study. Anesthesia was induced with thiopental 4 5 mg/kg and maintained with inhalation of N2O:O2 (1:1) and enflurane 1.0 2.0 vol%. Mivacurium 0.2 mg/kg was given as a muscle relaxant and then intubation performed after the twitch response was depressed more than 90%. Neuromuscular relaxation was assessed by TOF (T1) at the adductor pollicis with supramaximal stimulation of the ulnar nerve at 2 Hz every 12 seconds. The onset and duration of 5%, 25%, 50%, 75%, and 95% recovery time of T1 and recovery index were recorded. RESULTS: Onset of block was shortened but recovery time of 5%, 25%, 50%, 75%, 95% and recovery index were prolonged in patients with myasthenia gravis. CONCLUSIONS: In patients with myasthenia gravis, mivacurium induced rapid onset time and prolonged recovery time of 5%, 25%, 50%, 75%, 95% and recovery index.
Anesthesia ; Enflurane ; Humans ; Inhalation ; Intubation ; Kidney ; Liver ; Myasthenia Gravis* ; Neuromuscular Blockade ; Neuromuscular Diseases ; Orthopedic Procedures ; Plasma ; Pseudocholinesterase ; Relaxation ; Thiopental ; Thymectomy ; Ulnar Nerve

BACKGROUND: The hydrolysis of mivacurium and succinylcholine is impaired in the presence of defects of pseudocholinesterase. Clinical reports are conflicting as to the utility of anticholinesterases, in the reversal of mivacurium- or succinylcholine-induced paralysis. In this study, the role of exogenous bovine pseudocholinesterases (BpChE) and/or neostigmine, pyridostigmine, edrophonium or galanthamine in the reversal of mivacurium- or succinylcholine-induced paralysis, were investigated with the rat phrenic nerve-diaphragm preparation. METHODS: Ninety five Sprague-Dawley rats (200 g, male) were divided into 14 groups (n = 10). The phrenic nerve-diaphragm preparation mounted in a bath containing oxygenated Krebs' solution. Twitch response from diaphragmatic muscle evoked by phrenic nerve stimulation were measured. After stabilization of the twitch responses, mivacurium (0.1 microgram/mlml) or succinylcholine (0.1 microgram/ml) was administered incrementally in the preparation to obtain more than 95% twitch inhibition. BpChE (0.1, 1.0 u/ml), and/or neostigmine (0.1, 1.0 microgram/ml), pyridostigmine (0.5, 5 microgram/ml), edrophonium (0.01, 0.1 microgram/ml) or galanthamine (0.1, 1.0 microgram/ml) were added for the reversal of mivacurium- and/or succinylcholine-induced block in each group and the twitch responses (0.1 Hz) were monitored for 60 min. The effect of BpChE (0.1 u/ml), in combination with each of the above four anticholinesterases at lower concentrations also were examined. Twitch heights more than 75% was considered an adequatereversal. RESULTS: BpChE 0.1 and 1.0 u/ml were effective in reversal of mivacurium-induced paralysis. When anticholinestrases were added, there was no effective improvement of twitch height at the end of 60 minutes. In succinylcholine-induced paralysis, BpChE was effective for reversal, but when anticholinesterases were added, BpChE potency was inhibited. CONCLUSIONS: BpChE will reverse mivacurium-induced block more effectively than anticholinesterase. BpChE is effective in reversing succinylcholine block. The addition of anticholinesterases inhibits the activity of pseudocholinesterase.
Animals ; Baths ; Cholinesterase Inhibitors ; Edrophonium* ; Galantamine* ; Hydrolysis ; Neostigmine* ; Oxygen ; Paralysis* ; Phrenic Nerve ; Pseudocholinesterase* ; Pyridostigmine Bromide* ; Rats ; Rats, Sprague-Dawley ; Succinylcholine