Background: If the proportion of the spinal cord in the epidural space can be determined under C-arm fluoroscopy during cervical epidural block, a safe entry point for the epidural needle can be established. The aim of this study was the measurement of the cord to canal transverse diameter ratio of each cervical spines. Methods: We retrospectively evaluated the imaging data of 100 patients who underwent both cervical computed tomography (CT) and cervical magnetic resonance imaging (MRI) at our hospital. We measured the diameters of the spinal canal and spinal cord from the 3rd cervical vertebra to the 1st thoracic vertebra (T1) at each level by using the patients’ cervical CT and MRI images. The spinal cord and spinal canal diameters were measured in the transverse plane of the cervical MRI and CT images, respectively. Results: The spinal cord to spinal canal diameter ratio was the highest at the 4th and 5th cervical vertebrae (0.64 ± 0.07) and the lowest at T1 (0.55 ± 0.06, 99% CI [0.535, 0.565]. Conclusions Our findings suggest that the cord to canal transverse diameter ratio could be used as a reference to reduce direct spinal cord injuries during cervical epidural block under C-arm fluoroscopy. In the C-arm fluoroscopic image, if an imaginary line connecting the left and right innermost lines of the pedicles of T1 is drawn and if the needle is inserted into the outer one-fifth of the left and right sides, the risk of puncturing the spinal cord would be relatively reduced.

Prolotherapy is a non-surgical injection treatment method that repeatedly injects small amounts of proliferators into damaged ligaments, tendon, joints and surrounding tissues. The most common proliferator is a high concentration of glucose solution. Glucose solutions with a concentration of 10-25% are commonly used. Prolotherapy using glucose solution has few serious adverse events, but common side effects include post injection pain, stiffness, edema, and mild bleeding. There are many cases of complaining of pain caused by injection during or after prolotherapy. Some patients give up treatment if the pain is severe. A 43-year-old male patient visited the hospital with both elbow pain and left wrist pain, and prolotherapy was performed. In order to minimize pain during procedure and post injection pain of the patient, 10% glucose solution with 0.5% lidocaine was injected using a very fine needle of 30 G. The total number of treatments was eight. The patient did not complain of pain caused by needle insertion during procedure and post-injection pain. Chronic pain that lasted for two years after treatment almost disappeared. The patient was very satisfied with this treatment method and result.

Fluid management is an important component of perioperative care for patients undergoing neurosurgery. The primary goal of fluid management in neurosurgery is the maintenance of normovolemia and prevention of serum osmolarity reduction. To maintain normovolemia, it is important to administer fluids in appropriate amounts following appropriate methods, and to prevent a decrease in serum osmolarity, the choice of fluid is essential. There is considerable debate about the choice and optimal amounts of fluids administered in the perioperative period. However, there is little high-quality clinical research on fluid therapy for patients undergoing neurosurgery. This review will discuss the choice and optimal amounts of fluids in neurosurgical patients based on the literature, recent issues, and perioperative fluid management practices.

Anesthesiologists frequently see asymptomatic patients with diastolic dysfunction or heart failure for various surgeries. These patients typically show normal systolic function but abnormal diastolic parameters in their preoperative echocardiographic evaluations. The symptoms that are sometimes seen are similar to those of chronic obstructive pulmonary disease. Patients with diastolic dysfunction, and even with diastolic heart failure, have the potential to develop a hypertensive crisis or pulmonary congestion. Thus, in addition to conventional perioperative risk quantification, it may be important to consider the results of diastolic assessment for predicting the postoperative outcome and making better decisions. If anesthesiologists see female patients older than 70 years of age who have hypertension, diabetes, chronic renal disease, recent weight gain, or exercise intolerance, they should focus on the patient's diastologic echocardiography indicators such as left atrial enlargement or left ventricular hypertrophy. In addition, there is a need for perioperative strategies to mitigate diastolic dysfunction-related morbidity. Specifically, hypertension should be controlled, keeping pulse pressure below diastolic blood pressure, maintaining a sinus rhythm and normovolemia, and avoiding tachycardia and myocardial ischemia. There is no need to classify these diastolic dysfunction, but it is important to manage this condition to avoid worsening outcomes.
Blood Pressure ; Echocardiography ; Estrogens, Conjugated (USP) ; Female ; Heart Failure* ; Heart Failure, Diastolic ; Heart* ; Humans ; Hypertension ; Hypertrophy, Left Ventricular ; Myocardial Ischemia ; Pulmonary Disease, Chronic Obstructive ; Renal Insufficiency, Chronic ; Tachycardia ; Weight Gain

BACKGROUND: Synchrotron small-angle X-ray scattering (SAXS) is a very useful technique for experimental study of the nano-structure of the nervous system of animals. The study was designed to evaluate nerve preservation methods for the measurement of SAXS patterns. METHODS: Normal sciatic nerves extracted from male Sprague- Dawley rats were preserved in saline (N = 2), formalin (N = 2) or liquid nitrogen (N = 2) for 1 day, followed by measurement of SAXS patterns. SAXS patterns of normal sciatic nerves (N = 3) extracted just before the initiation of the experiment were used as controls. The study was carried out using the 4C1 beamline at Pohang Accelerator Laboratory in Korea. Incoming X-rays were monochromatized at 11 keV using a double multilayer (WB4C) monochromator with beam size of approximately 0.5 (V) × 0.8 (H) mm2. The exposure time was set at 60 sec, and 8 to 12 images per sample were acquired at a 0.5 mm interval. RESULTS: The periodic peaks of interfibrillar space between collagen fibrils were undetectable. The periodic peaks of the myelin sheath and collagen fibers were weakly detected or undetected in the nerves preserved in normal saline or formalin. The periodic peaks and intensity of the myelin sheath, collagen fibers, and interfibrillar space between collagens in the nerves preserved in liquid nitrogen were comparable to those of nerves in the ex vivo state. CONCLUSIONS: The study results indicated that preservation of nerves in liquid nitrogen is adequate for measurements with SAXS. However, saline and formalin preservation techniques were inadequate for SAXS measurement.
Animals ; Collagen ; Formaldehyde ; Gyeongsangbuk-do ; Humans ; Korea ; Male ; Methods* ; Myelin Sheath ; Nervous System ; Nitrogen ; Rats* ; Sciatic Nerve* ; Synchrotrons*

No abstract available.
Colorectal Surgery*

BACKGROUND: To understand the fundamentals of neural tissue injury, experiments on the nano-structured nerve system of animals are essential. This study was designed to reveal the nanostructure changes of an isolated ligatured rat sciatic nerve using the synchrotron small-angle X-ray scattering (SAXS) technique. METHODS: Male Sprague-Dawley rats (weighing approximately 250 grams) were used in this study. The SAXS patterns of 1 week after ligatured nerves (N = 5) and the normal sciatic nerves (N = 5) for the control were acquired after extracted approximately 15 mm before the experiment. Experiments were conducted at the 4C1 beam line at the Pohang Accelerator Laboratory in Korea. The exposure time was 60 sec, and 8 to 12 images per sample were acquired in 0.5 mm intervals, including the regions above, around and below the ligatured position. RESULTS: The periodic peaks of the myelin sheath and the interfibrillar space of collagen completely disappeared at the ligatured position. Farther from the ligatured point, weak and quite different SAXS patterns were observed for the myelin sheath and interfibrillar space. However, the collagen fiber peaks appeared at all positions, although they were weaker near the ligatured position. CONCLUSIONS: The ligature treatment totally destroyed the myelin sheath and interfibrillar space of collagen. In addition, retrograde degeneration developed 2 mm above the ligatured site. The myelin sheath and interfibrillar space of collagen were damaged 6 mm below the ligatured site. However, the collagen fiber structure was not significantly affected by the ligature, indicating a much different structural organization.
Animals ; Collagen ; Gyeongsangbuk-do ; Humans ; Korea ; Ligation ; Male ; Myelin Sheath ; Nanostructures ; Rats* ; Rats, Sprague-Dawley ; Retrograde Degeneration ; Sciatic Nerve* ; Synchrotrons*

BACKGROUND: During general anesthesia, a heated breathing circuit (HBC) is used to replace the heat and moisture exchange function of the upper airway. One HBC uses an air dryer filter that employs silica gel (SG) as a desiccant. SG is capable of adsorbing many organic compounds. Therefore, we undertook an in vitro study of the adsorption of desflurane by SG filters. METHODS: An HBC was connected to an anesthesia machine, and a test lung was connected to the circuit. The test lung was mechanically ventilated with 2 or 4 L/min of fresh gas flow, with and without the air dryer filter. Desflurane was administered at a 6 vol% on the vaporizer dial setting. The experiment was repeated 15 times in each group. The end-tidal concentrations were measured during the experiments. The air dryer filter weights were measured before and after the experiments, and the times required to achieve the specific end-tidal desflurane concentrations were determined. RESULTS: Significant differences in the end-tidal concentrations of desflurane were observed between the control and filter groups (P < 0.001). The filter weights increased significantly after the experiments (P < 0.001). The times required to achieve the same end-tidal desflurane concentrations were different with the application of the air dryer filter (P < 0.001). CONCLUSIONS: The adsorption of desflurane with the use of an air dryer filter was verified in this in vitro study. Careful attention is needed when using air dryer gel filters during general anesthesia.
Adsorption* ; Air Filters ; Anesthesia ; Anesthesia, General ; Desiccation ; Hot Temperature ; Lung ; Nebulizers and Vaporizers ; Respiration* ; Silica Gel* ; Weights and Measures

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*