Eye lens dosimetry in anesthesiology: a prospective study

The Impact of Implementing a Radiation-Sparing Protocol for Percutaneous Kyphoplasty-A Prospective Dosemetric Study

STUDY DESIGN

Prospective cohort study.

OBJECTIVES

The purpose of this prospective study was to evaluate a protocol for radiation-sparing kyphoplasty by assessing dosemetrically recorded radiation exposures to both patient and surgeon.

METHODS

This prospective clinical study examines the radiation exposure to patient and surgeon during single-level kyphoplasty in 32 thoracolumbar osteoporotic vertebral body fractures (12 OF 2, 9 OF 3, 11 OF 4 types) using a radiation aware surgical protocol between May 2017 and November 2019. The radiation exposure was measured at different locations using film, eye lens and ring dosemeters. Dose values are reported under consideration of lower detection limits of each dosemeter type.

RESULTS

A high proportion of dosemeter readings was below the lower detection limits, especially for the surgeon (>90%). Radiation exposure to the surgeon was highest at the unprotected thyroid gland (0.053 ± 0.047 mSv), however only slightly above the lower detection limit of dosemeters (0.044 mSv). Radiation exposure to the patient was highest at the chest (0.349 ± 0.414 mSv) and the gonad (0.186 ± 0.262 mSv). Fluoroscopy time, dose area product and number of fluoroscopic images were 46.0 ± 17.9 sec, 124 ± 109 cGy×cm2, and 35 ± 13 per kyphoplasty, respectively. Back pain significantly improved from 6.8 ± 1.6 to 2.5 ± 1.7 on the numeric rating scale on the first postoperative day (P < 0.0001).

CONCLUSIONS

The implementation of a strict intraoperative radiation protection protocol allows for safely performed kyphoplasty with ultra-low radiation exposure for the patient and surgeon without exceeding the annual occupational dose limits.

TRIAL REGISTRATION

The study was registered in the German Clinical Trials Register (DRKS00011908, registration date 16/05/2017).

Percutaneous structural cardiology: are anaesthesiologists properly protected from ionising radiation?

During transcatheter aortic valve implantations (TAVI) and other percutaneous structural procedures, some patients may need close anesthesiological care, thus exposing the anaesthesiologist to x-rays. This work aims to investigate the radiation dose received by anaesthesiologists during these specific procedures in order to improve their radiological protection. Occupational radiation doses were measured prospectively during percutaneous structural procedures in several health professionals using electronic dosimeters worn over the apron at chest level. A sample of 49 procedures were recorded, where the anaesthesiologists' average dose per procedure resulted 13 times higher than that of interventional cardiologists. The average dose per procedure received over the protection apron during TAVIs by the anaesthesiologist was 0.13 mSv, with a maximum value of 0.69 mSv. Taking these figures as a conservative estimation of the eye lens dose, an anaesthesiologist could participate in around 150 procedures before reaching the regulatory annual dose limit for the lens of the eye in Europe (20 mSv). In those clinical procedures where patients need close anesthesiological care, the anaesthesiologists might receive high radiation doses increasing the risk for cataracts and the risk of stochastic radiation effects. The proper use of occupational dosimeters will help identify these situations. It is recommended to use a mobile shielding barrier to reduce radiation exposure to acceptable levels in these situations.

Effectiveness of a radiation protective device for anesthesiologists and transesophageal echocardiography operators in structural heart disease interventions

In structural heart disease (SHD) interventions, the exposure of staff other than the first operator such as anesthesiologists and transesophageal echocardiography (TEE) operators to the radiation can also pose the risks of cancer and cataracts in the long term. This study was conducted to test our new radiation protective device (RPD) for anesthesiologists and TEE operators in SHD interventions. The RPD, which consists of a head side shield and a cradle shield, was mounted on a 0.25 mm Pb-equivalent unleaded radiation protection sheet on a self-made J-shaped acrylic table, and it was placed on the head side and cradle on the operating table. A CT human body phantom was placed on the operating table, and the C-arm was set in five directions: posteroanterior, right anterior oblique 30°, left anterior oblique 30°, caudal 30°, and cranial 30°. The ambient dose equivalent rate at the usual positions of the anesthesiologist and TEE operator were measured under a fluoroscopic sequence with and without the RPD, and the dose reduction rate was obtained. The height of each measurement point was set to 100, 130 or 160 cm. The reduction rates at the positions of the anesthesiologist and the TEE operator were 82.6-86.4% and 77.9-89.5% at the height of 100 cm, 48.5-68.4% and 83.3-91.0% at 130 cm, and 23.6-62.9% and 72.9-86.1% at 160 cm, respectively. The newly developed RPD can thus effectively reduce the radiation exposure of anesthesiologists and TEE operators during SHD interventions.

Risk of cataract in health care workers exposed to ionizing radiation: a systematic review

Background:

The eye is an important sensory organ occupationally exposed to ionizing radiation (IR) in healthcare workers (HCWs) engaged in medical imaging (MI). New evidence highlights the possible induction of cataract at IR exposure levels to be much lower than expected in the past.

Objective:

Conduct an updated review on the current evidence on cataract risk in healthcare workers exposed to IR.

Methods:

Published scientific studies on cataract risk in IR exposed healthcare workers were collected through a systematic search of two biomedical databases (MEDLINE and Scopus). Data from included studies was extracted and summarized. Study quality was also assessed.

Results:

All 21 eligible studies reported an increased prevalence of cataract, especially posterior subcapsular cataract, in IR exposed HCWs with a higher prevalence in interventional cardiology staff.

Discussion:

Our review synthesizes the latest evidence to support the hypothesis of a significantly increased risk of occupational cataract in healthcare workers operating MI and exposed to IR, especially in interventional cardiologists. Data also support a dose-response relationship between IR exposure and the prevalence of opacities, especially posterior subcapsular opacities.

Conclusions:

Findings highlight the need for effective control measures including appropriate training, adherence to protective procedures, and a constant use of shields and eye personal protective equipment in healthcare workers with optical exposure to IR. Periodic health surveillance programs, possibly including lens evaluation, are also important to monitor cataract risk in these MI operators.

Radiation Exposure of Anaesthetists Visualised by Real-time Dosimetry

BACKGROUND

Chronic exposure to occupational ionising radiation is seen as one reason for elevated cancer prevalence.

OBJECTIVE

The aim of this retrospective study was to evaluate radiation exposure of anaesthetists by real-time dosimetry.

METHODS

Data of 296 patients were analyzed. Ten types of trauma operation procedures including osteosynthesis of upper and lower extremity fractures and minimally invasive stabilisation of traumatic and osteoporotic vertebral fractures were accomplished. Evaluation was performed by an occupational dosimetry system, which visualises anaesthetists radiation exposure feedback compared to surgeons in real-time.

RESULTS

A significantly lower radiation exposure to anaesthetists compared to surgeons was observed in four types of operative procedures: Plate fixation of proximal humerus fractures, osteosynthesis of proximal femoral fractures, stabilisation of traumatic and osteoporotic vertebral fractures. In four types of operations (plate osteosynthesis of proximal humeral, distal radial and tibial fractures and intramedullary nailing of the clavicle), anaesthetists` amount of radiation exceeded one-third of the surgeons' exposure, especially if the C-arm tube was positioned close to the anaesthetists work station at the patients' head.

CONCLUSION

By using the occupational radiation dose monitoring system, radiation exposure to anaesthetists was visualised in real-time during trauma operations. Radiation exposure of anaesthetists depends on the type of operation and the position of the C-arm. The system may help to increase anaesthetists` awareness concerning radiation exposure and to enhance compliance in using radiation protection techniques.

Radiation Safety Perceptions and Practices Among Pediatric Anesthesiologists: A Survey of the Physician Membership of the Society for Pediatric Anesthesia

BACKGROUND

Pediatric anesthesiologists are exposed to ionizing radiation from x-rays on an almost daily basis. Our goal was to determine the culture of safety in which they work and how they adhere to preventative strategies that minimize exposure risk in their daily practice.

METHODS

After Institutional Review Board waiver and approval of the Society for Pediatric Anesthesia's research and quality and safety committees, an electronic e-mail questionnaire was sent to the Society's physician, nontrainee members and consisted of questions specific to provider use of protective lead shielding, the routine use of dosimeters, and demographic information. Univariate analyses were performed using the Wilcoxon rank sum test for ordinal variables, the Fisher exact test for categorical variables, and the Spearman test to analyze correlation between 2 ordinal variables, while a proportional odds logistic regression was used for a multivariable ordinal outcome analysis. P values of <.05 were considered statistically significant.

RESULTS

Twenty-one percent (674/3151) of the surveyed anesthesiologists completed the online questionnaire. Radiation exposure is ubiquitous (98.7%), and regardless of sex, most respondents were either concerned or very concerned about radiation exposure (76.8%); however, women were significantly more concerned than men (proportional odds ratio, 1.66 [95% confidence interval, 1.20-2.31]; P = .002). Despite this and independent of sex, level of concern was not associated with use of a radiation dosimeter (P = .85), lead glasses (odds ratio, 1.07 [95% confidence interval, 0.52-2.39]; P = 1.0), or a thyroid shield (P = .12). Dosimeters were rarely (13%) or never used (52%) and were mandated in only 28.5% of institutions. Virtually none of the respondents had ever taken a radiation safety course, received a personal radiation dose report, notification of their radiation exposure, or knew how many millirem/y was considered safe. Half of the respondents were female, and while pregnant, 73% (151/206) tried to avoid radiation exposure by requesting not to be assigned to cases requiring x-rays. These requests were honored 78% (160/206) of the time.

DISCUSSION

Despite universal exposure to ionizing radiation from x-rays, pediatric anesthesiologists do not routinely adhere to strategies designed to limit the intensity of this exposure and rarely work in institutions in which a culture of radiation safety exists. Our study highlights the need to improve radiation safety education, the need to change the safety culture within the operating rooms and imaging suites, and the need to more fully investigate the utility of dosimeters, lead shielding, and eye safety measures in pediatric anesthesia practice.

EYE LENS RADIATION EXPOSURE OF WORKERS DURING MEDICAL INTERVENTIONAL PROCEDURES AND SURGERY

To evaluates the eye-lens radiation exposure of workers during medical interventional procedures and surgery in a military hospital as well as of the equine veterinarians. The measures represent the exposure in a normal workload schedule of ninety randomly selected workers over a 3-month period, extrapolated to 1 year. The eye-lens dosemeters were placed near the eye closest to the radiation source (Carinou, E., Ferrari, P., Bjelac, O. C., Gingaume, M., Merce, M. S. and O'Connor, U. Eye lens monitoring for interventional radiology personnel: dosemeters, calibration and practical aspects of H p (3) monitoring. A 2015 review. J. Radiol. Prot. 2015;35(3): R17-R34). Three models of eye-lens dosemeters (Dosilab, Landauer and IRSN) were assessed in term of ergonomics. The annual estimation of eye-lens doses did not reach the annual dose limit of 20 mSv revised by the ICRP, ranged from 0.00 to 18.12 mSv with a mean of 0.96 ± 2.28 mSv. However, these results cannot be representative of a heavy workload or incident situations for which radiation exposure to the eye-lens could exceed this limit. The IRSN dosemeter model was considered the most convenient.