Dear Editor,
Noise is any sound that produces an unwanted physiological or psychological effect on an individual or group. In neurocritical care units (NCUs), where patients are often critically ill following traumatic brain injuries or neurosurgical emergencies, the environment plays a significant role in patient recovery. In the NCU setting, the impact of various noises from different sources is often overlooked. The detrimental effects of noise are compounded due to the delicate and vulnerable state of the patients, who often require optimal conditions for recovery.[1]
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[3] Patients in a state of high vulnerability are often recovering from traumatic events, with their bodies and brains under significant stress.[4] During this critical period, their physiological systems require a calm and supportive environment to promote healing.[5]
By the other side, the “Lombard effect” is defined as where an individual increases the volume of their speech to compensate for high levels of ambient noise. In this way, not only does noise increase but it can also compromise the quality of communication, causing misunderstandings, errors in patient care, and violations of confidentiality. Noise can interfere with healing in a variety of ways. The inability to communicate effectively in an intensive care unit (ICU) due to high noise levels can be an obstacle to the patient's ability to interact with caregivers, ask for assistance, or express discomfort. In the elderly or patients receiving ototoxic medications, noise exposure can further exacerbate hearing loss, affecting their ability to interact with their surroundings and caregivers and negatively affecting their overall well-being.
Noise causes emotional stress; loud, disruptive sounds can increase emotional stress in patients, making it more difficult for them to manage their condition. This stress can hinder recovery and extend the time spent in the ICU. Another effect is associated with cardiovascular stress; for patients recovering from surgery or with underlying cardiac conditions, noise serves as a stressor that can exacerbate cardiovascular instability. Research has shown that noise increases the levels of cortisol and catecholamines in the bloodstream, placing additional strain on the cardiovascular system ([Fig. 1]).
Fig. 1 Physiopathological effects of noise in neurotrauma critical care patients.
Sleep is essential for recovery, particularly for recovering all neurotrauma patients. Noise-related sleep disturbances characterized by insomnia, frequent awakenings, and disrupted sleep cycles are common in ICU settings and can delay recovery.
Chronic exposure to high noise levels leads to immunosuppression, making patients more susceptible to infections, leading to an imbalance in the body's metabolic responses, further complicating recovery. On the other hand, patients in neurocritical care are susceptible to disruptions in their brain function. Noise exposure can lead to arrhythmias and desynchronization of mechanical ventilation and can even disrupt sleep patterns, which are vital for brain recovery. Fragmented sleep can cause patients to be more disoriented, increasing the likelihood of confusion and delirium. The normal sleep–wake cycle is disrupted by a progressive inclination toward sleeping during daytime and awake during night shifts. This is due to the circadian rhythm, which is slightly longer as compared with the 24-hour day cycle. This is further aggravated by daytime interruptions including rounding, trips for procedures, and higher amounts of noise.
Concerning the effects of noise on health care providers, they face significant consequences as well. The environment of constant noise and disruption in the ICU can affect their performance and well-being, leading to emotional and psychological stresses. Health care workers exposed to high levels of noise experience higher levels of stress, which can contribute to burnout, anxiety, and depression. As noise increases cardiovascular stress in patients, it can also have detrimental cardiovascular effects on health care providers. Chronic exposure to noise in high-stress environments like ICUs has been linked to increased risks of hypertension and other cardiovascular diseases in health care workers. Noisy environments can affect the cognitive function of health care workers, leading to a reduction in the ability to concentrate, make decisions, and prioritize patients' needs in a timely manner. This undoubtedly increases the risk of medical errors. In addition, stress induced by noise can lead to interpersonal conflicts among members of health personnel and cause a deterioration in the work environment, which is usually very stressful and affects patient care.
The staff should be educated about the negative impact of noise on both patients and themselves. Simple measures including reducing the volume of alarms, ensuring quiet times for patients, reducing unnecessary noise, adjusting alarm thresholds, implementing noise-free periods during the day, using noise-reducing materials in ICU design, and implementing a formal noise-reduction protocol can help mitigate the risks associated with a noisy environment. The use of soundproofing technologies, such as noise-canceling devices or materials, can help reduce the amount of external noise in the ICU. Personal sound modulators, for example, can be used to reduce the perception of environmental noise while still allowing for the necessary communication between staff members. Incorporating noise-reduction protocols and technologies is essential for improving patient outcomes and enhancing the work environment for health care providers. Silence is a powerful, often underutilized therapeutic tool. By incorporating quiet times and reducing unnecessary noise, patients can experience better recovery outcomes. As we move toward more patient-centered care, understanding and managing the effects of noise should be recognized as an essential aspect of neurocritical care. This concept of “therapeutic silence” should be viewed as an integral part of ICU care, similar to other prophylactic measures like infection control protocols and medication safety checks.
Despite the considerable evidence of the detrimental effects of noise, it remains a pervasive issue in many NCUs. Many health care professionals, including intensivists and specialists, often do not consider noise to be a significant concern. However, the effects outlined above underscore the importance of addressing noise as part of a broader strategy for patient and staff well-being. In NCUs, where patients are at their most vulnerable, noise management is a critical component of recovery. We believe that it is important to implement noise management protocols. To address this issue, noise management should be considered a vital part of ICU care, just as hand hygiene and infection control are standard protocols.
