Noise in the OR: A Quality Improvement Program

For noise measurement and visual feedback, a SoundEar III device will be used. The SoundEar is the most studied and supported AV device maker in medical literature, with option of recording and providing visual feedback, designed specifically to "create awareness about noise". The device measures the environmental sound continuously and is also able to provide visual feedback indicating the actual sound level and has been extensively studied for uses in the clinical setting.

The technical specifications of the device are as follows: frequency range 20Hz to 16kHz and scope of measurement of 45dB(A) (similar to bird calls) to 115dB(A) (a sound level that can be encountered at a live rock music venue). The system provides optical feedback in 3 categories: green light (acceptable noise level), orange light (noise level is near the limit) and red light (noise level has exceeded the limit).

The L\&D ORs will be equipped with a sound measurement feedback device mounted on the wall visible from the foot end of the operating table. Noise recording can be conducted continuously for 24 hours a day, and downloaded, stored and analyzed weekly. The recorded sound level data can be time-matched with corresponding operations during time stamps.

The study will be divided into 4 phases.

Initially, a baseline validated Weinstein Noise Sensitivity questionnaire (WNS-6B) for subjective noise sensitivity will be collected for all potentially included primary resident surgeons9 as the variability in noise annoyance/disturbance is often best explained by individual subjective noise sensitivity than true noise level.

In phase 1, over a 4-6 month period, we will measure noise decibel level with the noise meter continuously with the optical feedback function concealed and pair this with all scheduled and unscheduled C-sections in the L\&D OR. The surgical team members will not specifically be told that data is being collected for a study, but the SoundEar devices will be visible to the surgical team during this phase. We will then plan to collect brief scale questionnaires on a visual analog scale adapted from Engelmann, et al. for all included study cases from the primary resident surgeon, the circulating RN and the patient regarding perceived noise level, stress level and overall experience. . Health care team members will serve as their own nested controls and thus the questionnaires will be de-identified and paired with a unique study ID number generated for each participant---- please note that the first page will only ask for the respondent's name and the questionnaire on the second page will not contain identifying information with the intention of removing the respondents name after their unique identifier has been transcribed to the questionnaire. These cases will serve as nested controls with each provider submitting a response serving as their own baseline control during statistical analysis and will be able to be linked to operative details and patient's chart from date and time noted for the delivery by the respondent. No identifying patient information will be collected on any of the paper questionnaires. Details about: case length, number of attendees in the operating room, blood loss, intraoperative complications, NICU involvement, NICU admission, maternal and neonatal length of stay, postoperative complications, readmissions, and reoperations will be obtained from the patient's chart in a prospective manner.

Each patients who consents to be in the study will complete one questionnaire. The patient will be informed that we are recording the noise levels in the OR during their surgery, and that we are studying the impact of noise levels in the OR on patient and physician stress levels and surgical outcomes.

Examples of the questionnaires are included with this application. The primary RN will also record the case type (scheduled, unplanned, urgent, or emergent), date and case start and stop time for time stamp reference, number of staff members in the L\&D OR and pertinent pediatric outcome data (APGAR, gestational age, NICU admission) in his/her portion of the survey. These cases will serve as "controls" and baseline noise data.

A two week washout period will then be planned during which no data will be collected. A difference in noise reduction of 3dB(A) is an important noise level reduction level as it represents a 50% reduction in perceived noise levels. A power calculation can be performed after phase 1 to calculate needed cases to demonstrate a statistical difference in noise reduction with intervention. From the literature, with an average decibel level of roughly 60 dB, and S.D. of 10 dB, 87 cases would be required to demonstrate statistical significance at 80% power.

In phase 2, the visual feedback function will be activated on the noise meters. Providers will be aware of the introduction of the device but receive no formal noise reduction education or knowledge that a study is being conducted in this phase. A threshold of ≤60dB(A) is generally accepted as an "acceptable" level and ≥65dB(A) as an excessive noise level based on the system providers recommendations and per results from previous studies in the medical literature. Optical feedback can then be accordingly activated in these 3 ranges (green light ≤60dB(A), orange light from 60-65dB(A), red light ≥65dB(A)). Similarly, we will collect overall noise data continuously during phase 2 and pair this with all scheduled and unscheduled C-sections in the L\&D OR with questionnaire data collected for comparison to the pre-intervention period.

For statistical analysis, surgeons and RN team members will be compared in nested control manner from the preintervention to postintervention time periods with planned sub-analysis of "high-responders" and "low-responders" from results of their previously obtained subjective WNS-6B questionnaires.

After data collection for phase 2, a phase 3 and 4 intervention period may be planned with intervening washout periods. These phases will take place after a 2 week formal education program on noise reduction, combined with the visual feedback function first disabled and then enabled with similar recording of continuous noise decibel level and survey data. The purpose of phase 3 and 4 will be in comparing outcomes from simple introduction of the device versus combined education program on noise awareness. The noise awareness program will also include a prompt that incorporation of noise reduction efforts are ongoing during preoperative time out. Initial sub-analysis of phase 1\&2 data should be planned for evaluating efficacy of the visual feedback device alone at improvement in noise outcomes (manuscript #1). Surgical and pediatric outcomes data will also be measured during all time periods for evaluation.

If the intervention is successful at improvement in surgeon stress or patient outcomes, the AV feedback noise meters may be considered for long term adoption into the L\&D ORs and future investigation of effectiveness in the Labor and Delivery Room (LDR) during vaginal births could be planned.