Toxicokinetics of paraquat in Korean patients with acute poisoning

To conduct a kinetic study of paraquat (PQ), we investigated 9 patients with acute PQ intoxication. All of them ingested more than 20 ml of undiluted PQ herbicide to commit suicide and arrived at our hospital early, not later than 7 h after PQ ingestion. The urine dithionite test for PQ in all of the nine patients was strongly positive at emergency room. Blood samples were obtained every 30 min for the first 2~3 h and then every 1 or 2 h, as long as the clinical progression was stable among the patients for 30 h after PQ ingestion. The area under the plasma concentration-time curve (AUCinf), which was extrapolated to infinity, was calculated using the trapezoidal rule. Toxicokinetic parameters, such as the terminal elimination half-life, apparent oral clearance, and apparent volume of distribution (Vd/F) were calculated. The maximum PQ concentration (Cmax) and the time to reach maximum PQ concentration (Tmax) were also obtained. Plasma PQ concentrations in nine patients were well described by a bi-exponential curve with a mean terminal elimination half-life of 13.1+/-6.8 h. Cmax and AUCinf were 20.8+/-25.7 mg/l and 172.5+/-160.3 h.mg/l, respectively. Apparent volume of distribution and apparent oral clearance were 50.9+/-61.3 l/kg and 173.4+/-111.2 l/h, respectively. There were a significant correlation (r =0.84; p<0.05) between the PQ amount ingested and Cmax. AUCinf also showed a significant correlation (r =0.83; p<0.05) with the PQ amount ingested. These correlations provide evidence that PQ has dose-linear toxicokinetic characteristics.

Popliteal sciatic nerve block versus spinal anesthesia in hallux valgus surgery / 대한마취과학회지

BACKGROUND: We compared clinical properties and patient satisfaction between spinal anesthesia and popliteal sciatic nerve block (PSNB) for hallux valgus surgery. METHODS: Forty patients undergoing hallux valgus surgery were divided into spinal group (spinal anesthesia with 2.5 ml of 0.5% bupivacaine [n = 20]) and PSNB group (PSNB with 30 ml of 0.75% ropivacaine mixed with 10 ml of normal saline solution using a nerve stimulator [n = 20]). The PSNB group used a patient-controlled-analgesia (PCA) pump for postoperative pain control. The quality and side effects were compared between the two groups. A questionnaire was used to evaluate patient satisfaction with the use of anesthetic techniques and postoperative pain control in the PSNB group. This study was assessed 3 days postoperatively by a blinded observer. RESULTS: Procedure time and time from anesthesia until start of sugery were significantly shorter in the spinal group than those in the PSNB group (P < 0.01). Anesthesia-related complications such as hypotension, bradycardia, shivering, nausea/vomitting, post-dural puncture headache (PDPH) and urinary retension were observed in 15%, 10%, 5%, 5%, 10%, and 20% of patients in the spinal group, respectively. PSNB was not associated with these complications. Patient satisfaction was slightly higher for PSNB than for spinal anesthesia. In the PSNB group, patient satisfaction with postoperative pain-control was 95% above ordinary satisfaction. CONCLUSIONS: Despite the long duration of the procedure, PSNB is relatively safe, provides an adequate level of anesthesia, effectively controls postoperative pain and reduces side effects. Therefore, PSNB could be a potential anesthetic technique for hallux valgus surgery.

Pneumomediastinum after functional endoscopic sinus surgery under general anesthesia: A case report / 대한마취과학회지

The occurrences of pneumothorax and pneumomediastinum are rare, but considered to be potentially life-threatening conditions in patients undergoing functional endoscopic sinus surgery under general anesthesia. Tracheobronchial rupture may results in serious complications, such as pneumothorax and pneumomediastinum. It may occur accidentally by endotracheal tube when the patient's neck is flexed or extended. We report the case of a 48-year-old female patient who developed massive subcutaneous emphysema, pneumothorax, pneumomediastinum and pneumoperitoneum seven hours after functional endoscopic sinus surgery under general anesthesia.

A Comparison Study on the Change in Lumbar Lordosis When Standing, Sitting on a Chair, and Sitting on the Floor in Normal Individuals

OBJECTIVE: To compare radiographic analysis on the sagittal lumbar curve when standing, sitting on a chair, and sitting on the floor. METHODS: Thirty asymptomatic volunteers without a history of spinal pathology were recruited. The study population comprised 11 women and 19 men with a mean age of 29.8 years. An independent observer assessed whole lumbar lordosis (WL) and segmental lordosis (SL) between L1 and S1 using the Cobb's angle on lateral radiographs of the lumbar spine obtained from normal individuals when standing, sitting on a chair, and sitting on the floor. WL and SL at each segment were compared for each position. RESULTS: WL when sitting on the floor was reduced by 72.9% than the average of that in the standing position. Of the total decrease in WL, 78% occurred between L4 to S1. There were significant decreases in SL at all lumbar spinal levels, except L1-2, when sitting on the floor as compared to when standing and sitting on a chair. Changes in WL between the positions when sitting on a chair and when sitting on the floor were mostly contributed by the loss of SL at the L4-5 and L5-S1 levels. CONCLUSION: When sitting on the floor, WL is relatively low; this is mostly because of decreasing lordosis at the L4-5 and L5-S1 levels. In the case of lower lumbar fusion, hyperflexion is expected at the adjacent segment when sitting on the floor. To avoid this, sitting with a lordotic lumbar curve is important. Surgeons should remember to create sufficient lordosis when performing lower lumbar fusion surgery in patients with an oriental life style.

Clinical and Radiological Findings of Nerve Root Herniation after Discectomy of Lumbar Disc Herniation

The authors report 2 cases of nerve root herniation after discectomy of a large lumbar disc herniation caused by an unrecognized dural tear. Patients complained of the abrupt onset of radiating pain after lumbar discectomy. Magnetic resonance imaging showed cerebrospinal fluid signal in the disc space and nerve root displacement into the disc space. Symptoms improved after the herniated nerve root was repositioned. Clinical symptoms and suggestive radiologic image findings are important for early diagnosis and treatment.

Hemodynamic effects of continuous intravenous injection and bolus plus continuous intravenous injection of oxytocin in cesarean section / 대한마취과학회지

BACKGROUND: Oxytocin may cause adverse cardiovascular effects, including tachycardia and hypotension, whereas the optimal dose of oxytocin at elective cesarean section is unclear. To determine the lowest effective dose of oxytocin, we studied the hemodynamic effects of three doses during spinal anesthesia for elective single cesarean delivery. METHODS: Sixty women received oxytocin by continuous (0.5 IU/min) or bolus-continuous (2 or 5 IU prior to 0.25 IU/min continuous intravenous injection) intravenous injection after clamping of the umbilical cord. We compared changes in heart rate (HR), mean arterial pressure (MAP) and estimated blood loss (EBL). Uterine tone (UT) was assessed by palpation on a linear analog scale (LAS) at 5, 10, 15, 20 and 25 minutes after the oxytocin injection. In addition, oxytocin-related side-effects such as nausea and vomiting were recorded. RESULTS: Marked hemodynamic changes such as HR and MAP occurred in the bolus-continuous groups but not in the continuous groups. Although we were not able to observe a variation of EBL in each group, the UT significantly increased in the bolus-continuous groups when compared with that the continuous groups. In addition, the hemodynamic changes such as HR and MAP were lower in the two IU bolus-continuous group than those in the five IU group. CONCLUSIONS: Although bolus-continuous injection of oxytocin resulted in more hemodynamic changes than continuous injection, bolus-continuous injection had a greater effect on uterine contraction. Furthermore, two IU bolus-continuous injection showed lower hemodynamic changes than in the five IU bolus-continuous injection.

Comparison of time to awareness between obese patients and non-obese patients after total intravenous anesthesia with propofol and remifentanil

BACKGROUND: The rate of obesity has reached epidemic proportions and is on the rise.There have not been adequate studies on the differences in anesthesiology in obese patient. For this reason, we designed this study to determine the effect of obesity on time to awareness, comparing the use of propofol and remifentanil in general anesthesia. METHODS: We enrolled 55 patients into the study, between ages 16 and 45 years, who had an ASA physical status 1, 2 and who were undergoing general anesthesia for an elective obstetric operation. According to the Asia-Pacific obesity criteria, we divided the patients into 2 groups, the obesity group (BMI > or = 25), and the non-obesity group (BMI < 25). Propofol and remifentanil were infused using TCI for general anesthesia. The bispectral index score (BIS) was used for monitoring depth of anesthesia.During each operation, we tried to keep the BIS between 40 and 55 by controling the target concentration of TCI.We compared the time-to- awareness between the obese patient group and the non-obese patient group. RESULTS: The obesity and the non-obesity group did not show significant difference in awareness times between the obesity group, 412.4 +/- 102.5 s and the non-obesity group, 434.1 +/- 49.1 s. CONCLUSIONS: There was no evidence of a significant difference in time-to-awareness between the obese patient group and the non-obese patient group.The use of remifentanil and propofol work equally well in obese and in non-obese patients anesthesized for elective surgery.

Green urine in a patient who received a continuous infusion of propofol: A case report / 대한마취과학회지

The color of urine in patients who receive anesthetic gives much medical information to a medical team. So, we must check the urine color and know the cause of discoloration of the urine from anesthetic patients. Green urine is rare indeed and it is a benign potential side effect of propofol; this phenomenon is related to the metabolism of propofol. We experienced green urine from a long-term anesthetized patient who received a continuous infusion of propofol. We report here on this unusual case and we review the relevant literature.

Outcome of Atypical Meningioma

OBJECTIVE: Limited data are available concerning the outcome of the patients with atypical meningioma due to lack of the studies with large series. The authors review atypical meningioma retrospectively and analyzed various parameters concerning its outcome. METHODS: Of the 866 meningioma patients treated between 1990 and 2003, pathologically proven 54 atypical meningiomas were reviewed. Various factors of the patients were analyzed, and surgical specimens were re-examined blindly by neuropathologist without any patient information. Extent of surgical resection was determined according to Simpson's classification by reviewing the chart and postoperative scan if possible. RESULTS: Twenty-three (42.6%) had local recurrences during the follow-up, of which 13 (32.5%) of 40 complete excisions and 10 (71.4%) of 14 incomplete excisions. The median time to recurrence was 47 months, and the overall 3-, 5-, and 10-year local control rates were 62.4%, 41.5%, and 31.1%, respectively. Five (9.3%) died during follow-up period. The mean survival time was 123 months, and the overall 3-, 5-, and 10-year survival rates were 94.2%, 87.2%, and 78.5%, respectively. The extent of surgical excision was the most significant prognostic factor not for survival but for local control (p=0.2179 and 0.0005, respectively). Extracranial metastasis was not seen in our cases. CONCLUSION: Complete surgical excision is the most important factor in improving local control. Careful long-term follow-up is mandatory because atypical meningioma shows a broad range of aggressiveness and natural history.

The Effectiveness of Low Dose Fentanyl Bolus Injection in Cesarean Section after Umbilical Cord Clamping / 대한마취과학회지

BACKGROUND: For anesthesia in cesarean section N2O and low concentrations of inhalation anesthetics are regarded as the anesthetic agent of choice. But a low level of anesthesia frequently leads to increased maternal hemodynamic responses and awareness. The effects of a 3 microgram/kg fentanyl bolus injection after umbilical cord clamping was evaluated in 20 full-term parturients, scheduled for elective cesarean section, versus to 20 parturients without fentanyl. METHODS: The forty parturients (ASA physical status 1, 2) scheduled for cesarean section were randomized to either a N2O-enflurane (E group) or a N2O-enflurane-fentanyl (F group). Thiopental sodium (4 mg/kg) and succinylcholine (1.5 mg/kg) were administered intravenously for the induction and endotracheal intubation. Anesthesia was maintained with 50% N2O and 1% enflurane in oxygen until delivery. After delivery, the intravenous injection of 0.5 mg/kg of atracurium was administered, controlled ventilation was applied to maintain PetCO2 at 30 to 35 mmHg with N2O (3 L/min) and O2 (1.5 L/min). Immediately after clamping the umbilical cord, 3 microgram/kg of fentanyl (F group only) was administered. Heart rate, blood pressure, awareness, recovery time, postoperative complication and recall were evaluated. RESULTS: Heart rate values at 10 and 20 min after umbilical cord clamping and 5 min after extubation, and mean arterial pressure at 5, 10 and 20 min after umbilical cord clamping in group F were found to be significantly lower than in group E. CONCLUSIONS: We conclude that N2O-enflurane-fentanyl at 3 microgram/kg is clinically satisfactory in anesthesia for cesarean section, having no adverse effects on the mother.

A Case of Recurrent Transient Monocular Blindness in Systemic Lupus Erythematosus patient with Antiphospholipid Antibody Syndrome

Transient monocular blindness (TMB) may occur in patients with systemic lupus erythematosus (SLE). Several mechanisms have been suspected as the causes of such TMBs. A 32-year-old female patient with SLE presented recurrent monocular altitudinal visual field defects lasting for several minutes and occurring less than six times per day. Her anticardiolipin antibody level was persistently positive. All cerebrovascular imagings were normal. We report a case of recurrent TMBs in SLE with antiphospholipid antibody syndrome, which may have been induced by vasospasm.

Comparison of Gastric Volume and Acidity between Children and Adults / 대한마취과학회지

BACKGROUND: Aspiration of gastric contents into the lungs is one of the most feared complications during anesthesia. Various factors combine to make pediatric patients more susceptible to regurgitation and aspiration than adults. We compared the risk of incidence of acid aspiration in two groups, after examining the pH, and volume of gastric contents in pediatric and adult patients. METHODS: This study was carried out with inpatients scheduled for elective surgery under general anesthesia. Sixty patients from 1 to 13 years old were included in the pediatric age group, and sixty patients from 18 to 60 years old were included in the adult age group. After induction of anesthesia and stabilization of the condition of the patient, gastric contents were collected via a 10 - 18 French Salem Sump tube. Gastric volume and pH were measured. RESULTS: The mean gastric volume in the pediatric group was significantly higher than those in the adult group, whereas, The mean gastric pH in the adult group was significantly higher than those in the pediatric group. CONCLUSIONS: We concluded that pediatric patients have a lower gastric pH but a higher gastric volume than adult patients.

Two Cases of Callosal Disconnection Syndrome: Impaired Body Cognition of Nondominant Limbs

Callosal disconnection results in the functional independence of each hemisphere and usually produces characteristic signs including alien hand, left-sided apraxia, left agraphia and left tactile anomia. Our two patients; a 75-year-old right-handed woman with hypertension and a 71-year-old right-handed woman with diabetes mellitus, showed impairments in the identification of body parts with their left hands in addition to characteristic symptoms such as left ideomotor apraxia, agraphia, tactile anomia, and right alien hand signs with groping and grasping. Brain MRIs of these patients upon admission demonstrated infarcts in the medial portion of the left frontal lobes and in the corpus callosum supplied by the left anterior cerebral artery. The impairment of body parts cognition in our patients can be attributed to the failure of the patient's left hand to communicate with the body schema stored in the left hemisphere.