Methods for Measuring and Identifying Sounds in the Intensive Care Unit

Area of Science:

• Environmental Health
• Clinical Engineering
• Acoustics

Background:

• Excessive noise in intensive care units (ICUs) is a persistent problem.
• Inconsistent measurement methods hinder cross-study comparisons and progress.
• A standardized approach is needed to improve the reliability of ICU noise research.

Purpose of the Study:

• To present a general method for measuring sound pressure levels and identifying sound sources in the ICU.
• To provide a detailed, reproducible guideline for future research.
• To demonstrate the feasibility of the proposed method through collected data.

Main Methods:

• Developed a general method with two procedures: sound pressure level measurement using sound level meters and sound source identification via observers.
• Applied the general method over a 24-hour period in a four-bed ICU room, focusing on two beds.
• Utilized four sound level meters and four observers, with observers working in shifts.

Main Results:

• Achieved good to excellent interrater reliability (>0.75) for most (19/24 and 16/24) sound categories.
• Recorded average equivalent sound pressure levels (L_Aeq) of 54.12 dBA (day), 53.37 dBA (evening), and 49.05 dBA (night).
• Identified talking (39.29%) and human-generated sounds (37.30%) as predominant noise sources over 24 hours.

Conclusions:

• A general method for measuring ICU sound pressure levels and sources was successfully described and applied.
• The method's feasibility was confirmed through 24-hour data collection.
• High interrater reliability supports the method's suitability for future standardized ICU noise studies.