Subacute Combined Degeneration with Motor Neuropathy Following Nitrous Oxide Abuse

The neurotoxicity of nitrous oxide (N2O) is known to be mainly occurred by interference with action of vitamin B12. A 38-year-old male presented with progressive gait instability after recreational inhalational use of N2O for 2 months. Although spine magnetic resonance image showed typical subacute combined degeneration, nerve conduction study showed motor neuropathy that is atypical findings of vitamin B12 deficiency. This case suggests N2O-induced neuropathy can develop separately from a vitamin B12 deficiency.

Subacute Combined Degeneration with Motor Neuropathy Following Nitrous Oxide Abuse

The neurotoxicity of nitrous oxide (N2O) is known to be mainly occurred by interference with action of vitamin B12. A 38-year-old male presented with progressive gait instability after recreational inhalational use of N2O for 2 months. Although spine magnetic resonance image showed typical subacute combined degeneration, nerve conduction study showed motor neuropathy that is atypical findings of vitamin B12 deficiency. This case suggests N2O-induced neuropathy can develop separately from a vitamin B12 deficiency.

Acute Median Neuropathy after Subdermal Contraceptive Implant Removal

The contraceptive implant is an effective and well-established method of contraception. A 43-year-old woman presented with paresthesia and weakness of left hand. Symptoms began 3 weeks ago, immediately after removal of a contraceptive device in the left arm. A nerve conduction study showed proximal median neuropathy, and ultrasonography revealed focal swelling of the median nerve at the level of removal. Although nerve damage is a rare complication, special care should be taken to avoid nerve injury during removal procedure.

Transient right hemidiaphragmatic paralysis following subclavian venous catheterization: possible implications of anatomical variation of the phrenic nerve: a case report / 대한마취과학회지

Phrenic nerve paralysis is an unusual complication associated with central venous catheterization. Various mechanisms have been proposed. We present a case of transient right hemidiaphragmatic paralysis after subclavian venous catheterization. We hypothesize that anatomical variation of the phrenic nerve was responsible for this complication.

A Case of Bilateral Acute Macular Neuroretinopathy after URI

PURPOSE: To report a case of bilateral acute macular neuroretinopathy (AMN) following flu-like illness. CASE SUMMARY: A 42-year-old woman complained of paracentral scotoma in both eyes 2 weeks after an episode of flu. Fundus examination showed several dark, brown-reddish, wedge-shaped lesions in both maculae, and red-free fundus photography confirmed the lesions. Fluorescein and indocyanine green angiography was normal. Amsler grid test demonstrated paracentral scotoma. The multifocal electroretinogram (ERG) response was subnormal, and ocular coherence tomography (OCT) confirmed an impaired photoreceptor layer in both eyes. Under the diagnosis of AMN, the patient was followed-up without treatment. No subjective changes were observed during follow-up, although the damage to the photoreceptor was partially recovered based on spectral-domain OCT (SD-OCT). CONCLUSIONS: Multifocal ERG and SD-OCT may be helpful to diagnose AMN. Despite partial recovery of clinical signs on SD-OCT, paracentral scotoma could be sustained for a long period of time.

Post-cannulation Radial Artery Aneurysm in a Patient Undergoing Mitral Valvular Replacement: A case report / 대한마취과학회지

Radial artery is the most common site which is chosen for the continuous monitoring of arterial blood pressure and blood sampling in the critically ill patients. This method is regarded as a safe one though there are various complications. In most complications, the clinical sequelae do not have much significances. However, serious complications have been reported including cerebral embolism, or ischemic necrosis of hand or forearm requiring amputation although the incidences are rare. Post-cannulation radial artery aneurysm is not common in clinical practices. We report a case of post-cannulation radial artery aneurysm in a 23-year-old female patient undergoing mitral valvular replacement. Radial artery cathteter was indwelt for 14 days at the same site. It should be kept in mind that aseptic and atraumatic technique must be used and the catheter must not be indwelt at one point for a long time in arterial cannulation.

Cardiovascular Blunting Effect of Magnesium Sulfate following Tracheal Intubation in Parturients undergoing Cesarean Section / 대한마취과학회지

Background; Tracheal intubation for cesarean section is usually performed with rapid sequence induction. Under this light stage of anesthesia, marked hypertensive changes of maternal hemodynamic responses following tracheal intubation may occur, which are the common cause of maternal and neonatal complications. We have studied the maternal cardiovascular blunting effect of magnesium sulfate following tracheal intubation in cesarean section. Methods; After obtaining the written informed consents, ninety ASA class I parturients scheduled for cesarean section were randomly allocated to one of three groups: group 1 received thiopental 4 mg/kg and succinylcholine 1.5 mg/kg, group 2 received fentanyl 1.5 microgramg/kg additionally, and group 3 received fentanyl 1.5 microgramg/kg and MgSO4 40 mg/kg additionally. Systolic, mean, diastolic blood pressure, and heart rate were measured before induction, immediately after intubation. Serum magnesium concentrations were measured before administering magnesium and near the end of surgery. Train of four ratio was monitored during whole period of anesthesia. Neonatal Apgar scores and neurologic and adaptive capacity scores (NACS) were checked. Results; Blood pressure changes were more stable in group 2 and group 3, especially group 3, than group 1 (p<0.05). No statistical differences were found in heart rate changes in all groups. No significant differences were noted in neuromuscular recoveries, neonatal Apgar scores and NACS. Conclusions; Magnesium sulfate may be successfully used for blunting the cardiovascular response to tracheal intubation in parturients undergoing general anesthesia for cesarean section.

In Vitro Compatibility Test of Packed Erythrocytes and Harmann`s solution / 대한마취과학회지

Packed erythrocytes (PC) are used to treat intraoperative blood loss and frequently re- constituted with normal saline (NS) to overcome the slow infusion rate due to high viscosity and inadequate volume replacement. It has been recommended that calcium containing solutions such as Hartmann's solution (HS) should not be used as a diluent of PC, citing possible clot formation whenever the level of ionized calcium reaches a concentration capable of catalyzing the coagulation cascade. We studied in vitro coagulation propensity, if any, by analyzing the mixtures of PC with different amounts of HS or NS in ratios between 10: 0 to 1: 9 (PC: crystalloids). These mixtures were analyzed for ionized calcium concentration, pH, Hct and checked for the gross indication of clot formation at room temperature. No clot formation was found in NS-reconstituted samples, however, 55 of 100 HS-reconstituted samples were present with clot formation. In these samples, the initial clot formations were found at ratios of 6: 4 (1case at 45 min), 5: 5 (1 case at 45 min, 1 case at 60 min, 3 cases at 90 min), 4: 6 (1 case at 45 min, 3 cases at 60 min) and the mean ionized calcium concentration of initial clotting was 0.304+/-0.089 mM/L In conclusion, as much as 100ml of Hartmann's solution can be safely usedas a diluent of one unit of PC in patients requiring rapid blood transfusion.