震耳欲聋：带锯噪声的模拟评估。

Department of Orthopaedic Surgery, Dwight D. Eisenhower Army Medical Center, Fort Gordon, GA.

Department of Public Health, US Army Medical Activity, Fort Wainwright, AK.

J Pediatr Orthop. 2021;41(10):e889-e893. doi: 10.1097/BPO.0000000000001941.

BACKGROUND

Orthopaedic cast saws are an integral component to a pediatric orthopaedic practice but can also be associated with patient anxiety and noise exposure for patient. Although previous studies have deemed the noise generation from orthopaedic cast saws to be within safe occupational exposure levels, no study to date has compared the noise generation from a cast saw used in various exam room settings.

METHODS

A simulated fiberglass cast model was used. Noise generation was assessed using calibrated sound level meters with measurements performed at 18 inches, 36 inches, and 6 ft measured from the cast saw. Measurements were performed in 1 of 2 clinical settings: (1) an open bay setting and (2) an enclosed exam room. In the enclosed exam room, the 6-foot measurement was performed behind the closed exam door. An orthopaedic cast saw with built-in vacuum was used to continuously cut the fiberglass model for 1 minute with measurements of peak and mean sound generation, recorded in decibels (dB), a logarithmic scale. Three measurements were recorded at each distance. Between group comparisons were performed with statistical significance set at P=0.05.

RESULTS

Baseline sound levels were similar between cohorts with progressive decreases in mean sound with increasing distance from the saw. Mean sound levels were significantly higher in the enclosed room setting at 18 inches (92.8 dB, 95% confidence interval (CI): 91.72-93.88 vs. 90.6 dB, 95% CI: 89.91-91.29; P=0.043] and 36 inches (90.3 dB, 95% CI: 89.9-90.7 vs. 86.0 dB, 95% CI: 85.18-86.82; P=0.017). At 6-ft distance, however, the enclosed room demonstrated a 13.8-fold sound reduction compared with the open bay (72.0 dB, 95% CI: 71.59-72.4 vs. 83.4 dB, 83.14-83.72; P<0.001).

CONCLUSION

By closing the exam door, a 13-fold reduction in noise exposure can be achieved for adjacent patients and personnel. Consideration should be given for using orthopaedic cast saws in an enclosed exam room to prevent unnecessary noise exposure with hearing protection of cast saw operators and treated patients.

CLINICAL RELEVANCE

Orthopaedic cast removal.

背景

矫形外科学石膏锯是小儿矫形外科实践的一个组成部分，但也会引起患者焦虑和噪音暴露。尽管先前的研究认为矫形外科学石膏锯产生的噪音在安全的职业暴露水平内，但迄今为止，没有研究比较在不同诊室环境中使用的石膏锯产生的噪音。

方法

使用模拟的玻璃纤维石膏模型。使用校准的声级计进行噪音产生评估，在距离石膏锯 18 英寸、36 英寸和 6 英尺处进行测量。在 2 种临床环境下进行测量：（1）开放式诊室环境和（2）封闭的检查室。在封闭的检查室中，在关闭的检查门后面进行 6 英尺的测量。使用内置真空的矫形石膏锯连续切割玻璃纤维模型 1 分钟，记录峰值和平均噪音产生，以分贝（dB）表示，这是一个对数刻度。在每个距离处记录 3 次测量。使用统计学意义 P=0.05 进行组间比较。

结果

基线声级在队列之间相似，随着与锯的距离增加，平均声级逐渐降低。在封闭的房间设置中，平均声级在 18 英寸（92.8dB，95%置信区间（CI）：91.72-93.88 与 90.6dB，95%CI：91.72-91.88；P=0.043）和 36 英寸（90.3dB，95%CI：90.3-90.7 与 86.0dB，95%CI：85.18-86.82；P=0.017）处明显更高。然而，在 6 英尺的距离处，与开放式诊室相比，封闭的房间显示出 13.8 倍的噪音减少（72.0dB，95%CI：71.59-72.4 与 83.4dB，95%CI：83.14-83.72；P<0.001）。