Radiation Exposure of the Hand and Chest during C-arm Fluoroscopy-Guided Procedures

BACKGROUND: The C-arm fluoroscope is an essential tool for the intervention of pain. The aim of this study was to investigate the radiation exposure experienced by the hand and chest of pain physicians during C-arm fluoroscopy-guided procedures. METHODS: This is a prospective study about radiation exposure to physicians during transforaminal epidural steroid injection (TFESI) and medial branch block (MBB). Four pain physicians were involved in this study. Data about effective dose (ED) at each physician's right hand and left side of the chest, exposure time, radiation absorbed dose (RAD), and the distance from the center of the X-ray field to the physician during X-ray scanning were collected. RESULTS: Three hundred and fifteen cases were included for this study. Demographic data showed no significant differences among the physicians in the TFESIs and MBBs. In the TFESI group, there was a significant difference between the ED at the hand and chest in all the physicians. In physician A, B and C, the ED at the chest was more than the ED at the hand. The distance from the center of the X-ray field to physician A was more than that of the other physicians, and for the exposure time, the ED and RAD in physician A was less than that of the other physicians. In the MBB group, there was no difference in the ED at the hand and chest, except for physician D. The distance from the center of the X-ray field to physician A was more than that of the other physicians and the exposure time in physician A was less than that of the other physicians. CONCLUSIONS: In conclusion, the distance from the radiation source, position of the hand, experience and technique can correlate with the radiation dose.

The Survey about the Degree of Damage of Radiation-Protective Shields in Operation Room

BACKGROUND: Medical doctors who perform C-arm fluoroscopy-guided procedures are exposed to X-ray radiation. Therefore, radiation-protective shields are recommended to protect these doctors from radiation. For the past several years, these protective shields have sometimes been used without regular inspection. The aim of this study was to investigate the degree of damage to radiation-protective shields in the operating room. METHODS: This study investigated 98 radiation-protective shields in the operation rooms of Konkuk University Medical Center and Jeju National University Hospital. We examined whether these shields were damaged or not with the unaided eye and by fluoroscopy. RESULTS: There were seventy-one aprons and twenty-seven thyroid protectors in the two university hospitals. Fourteen aprons (19.7%) were damaged, whereas no thyroid protectors (0%) were. Of the twenty-six aprons, which have been used since 2005, eleven (42.3%) were damaged. Of the ten aprons, which have been used since 2008, none (0%) was damaged. Of the twenty-three aprons that have been used since 2009, two (8.7%) of them were damaged. Of the eight aprons used since 2010, one (12.3%) was damaged. Of the four aprons used since 2011, none (0%) of them were damaged. The most common site of damage to the radiation-protective shields was at the waist of the aprons (51%). CONCLUSIONS: As a result, aprons that have been used for a long period of time can have a higher risk of damage. Radiation-protective shields should be inspected regularly and exchanged for new products for the safety of medical workers.

A Randomized Controlled Trial about the Levels of Radiation Exposure Depends on the Use of Collimation C-arm Fluoroscopic-guided Medial Branch Block

BACKGROUND: C-arm fluoroscope has been widely used to promote more effective pain management; however, unwanted radiation exposure for operators is inevitable. We prospectively investigated the differences in radiation exposure related to collimation in Medial Branch Block (MBB). METHODS: This study was a randomized controlled trial of 62 MBBs at L3, 4 and 5. After the patient was laid in the prone position on the operating table, MBB was conducted and only AP projections of the fluoroscope were used. Based on a concealed random number table, MBB was performed with (collimation group) and without (control group) collimation. The data on the patient's age, height, gender, laterality (right/left), radiation absorbed dose (RAD), exposure time, distance from the center of the field to the operator, and effective dose (ED) at the side of the table and at the operator's chest were collected. The brightness of the fluoroscopic image was evaluated with histogram in Photoshop. RESULTS: There were no significant differences in age, height, weight, male to female ratio, laterality, time, distance and brightness of fluoroscopic image. The area of the fluoroscopic image with collimation was 67% of the conventional image. The RAD (29.9 +/- 13.0, P = 0.001) and the ED at the left chest of the operators (0.53 +/- 0.71, P = 0.042) and beside the table (5.69 +/- 4.6, P = 0.025) in collimation group were lower than that of the control group (44.6 +/- 19.0, 0.97 +/- 0.92, and 9.53 +/- 8.16), resepectively. CONCLUSIONS: Collimation reduced radiation exposure and maintained the image quality. Therefore, the proper use of collimation will be beneficial to both patients and operators.

Erratum: Growth suppression of four cancer cells by hyperbaric nitrous oxide and methotrexate (Korean J Anesthesiol 2010; 58(1): 61-69) / 대한마취과학회지

No abstract available.

Growth suppression of four cancer cells by hyperbaric nitrous oxide and methotrexate / 대한마취과학회지

BACKGROUND: Nitrous oxide concentration is easily controlled by respiratory ventilation. It suppresses bone marrow via the inhibition of thymidylate synthesis. The aim of this work was to determine the optimal pressure and exposure duration of nitrous oxide, as well as methotrexate concentration that maximizes the suppression of 4 cancer cells: CCRF-CEM, K562, A549 and MDA-MB-231. METHODS: Each cancer cell was cultured in a hyperbaric chamber at 1, 2 and 3 atmosphere of 74% nitrous oxide for 24, 48, and 72 hours at 0, 0.3, 0.7, 1, 2, 5 and 10 microM methotrexate (MTX), respectively. The results were expressed in the ratio of the number of cancer cells cultured under specific conditions (S cells) to that under normal conditions (N cells). RESULTS: The S/N ratio of CCRF-CEM cells was 87.4% in 24-hour culture, 95.0% in 48-hour culture and 115.9% in 72-hour culture (P 0.05). However, the S/N ratio of MDA-MB 231 cells was 66.9% in 24-hour culture, 83.1% in 48 hour culture and 87.8% in 72-hour culture (P < 0.05). CONCLUSIONS: Only the growth of the MDA-MB-231 cells was significantly reduced after a longer exposure time to nitrous oxide, but those of the other cells were not.

Effect of midazolam premedication on the onset of propofol and rocuronium during propofol target-controlled infusion / 대한마취과학회지

BACKGROUND: This clinical study was designed to evaluate the effect of midazolam as a premedication on the onset of propofol and rocuronium during propofol target-controlled infusion (TCI). METHODS: Seventy four patients (ASA class I or II) were randomly allocated to receive either no premedication (control group) or premedication with 0.04 mg/kg intravenous midazolam (midazolam group). Anesthesia was induced and maintained with propofol TCI. Time from propofol injection to loss of consciousness (LOC) and estimated effect concentration at LOC were recorded. After LOC, rocuronium (0.6 mg/kg) was injected. We monitored the degree of neuromuscular blockade by acceleromyography. The following parameters were measured and compared between groups: Time from rocuronium injection to depression of twitch height below 25%, time to maximal depression of twitch height (defined as rocuronium onset time). RESULTS: Systolic blood pressure before induction was lower in midazolam group (125 +/- 15 vs 135 +/- 20 mmHg), however, there was no difference in blood pressure at LOC between groups (111 +/- 16 vs 106 +/- 21 mmHg). In midazolam group, time to LOC in propofol TCI was shorter (63 +/- 22 vs. 203 +/- 118 sec) and estimated effect site concentration of propofol was significantly lower than control group (0.9 +/- 0.3 vs. 2.2 +/- 0.4 microl/ml). The onset time of rocuronium was not different between groups (120 +/- 39 vs. 137 +/- 42 sec). CONCLUSIONS: Midazolam pretreatment fastens the onset time of propofol and decreases the propofol requirement for LOC. However, it does not influence the onset of rocuronium.