Fight the noise


Hello, Ms. Earshot, my name's Dr. Bellow. What brings you in today? Did you say you're feeling meeker? Oh, weaker. Actually, I think I heard you that time, and what makes you think I'm a proctor? Oh, doctor! You want me to do you a favor? You have a fever? That makes more sense. Could you speak a bit louder and tell me how long you have been in Spain?

We all know the difficulty in functioning within a noisy hospital. Patients and families chattering, machines buzzing and pinging, hospital staff shouting orders, construction workers banging: The sound levels could often be mistaken for a casino or a pub. But in hospitals we don't always have the option of suggesting that we move our discussion to a quiet coffee shop instead. Noise pollution in hospitals is an issue that confronts us all as hospital workers.

In 1999, the World Health Organization produced “Guidelines for Community Noise,” which state that noise should not exceed an average of 30 dB in hospital rooms and that peaks should not exceed 40 dB during the night. To put those numbers in perspective, a vacuum cleaner is between 70 to 80 dB, a normal voice is between 50 to 60 dB and a quiet library is around 30 dB.

How do hospitals measure up to these targets? A study of a general surgical ward in the United Kingdom (J Clin Nurs. 2005;14(2):156-64) found that sound levels averaged 42.28 dB with peaks reaching 70 dB. The minimum level was 36 dB between midnight and 7 a.m. The same author determined that sound levels in an intensive care unit averaged 56.42 dB with spikes reaching 80 dB and a minimum of 50 dB (Nurs Crit Care. 2007;12(4):188-97). An average level of 30 dB seems like a very distant goal.

I'm going to listen to your heart, Ms. Earshot. I'm pretty sure I heard your first and second heart sounds. I think there might be a murmur but can't be certain. I'll need some quiet for a moment to hear it. Could you stop talking, Ms. Earshot? Oh, you weren't talking. I'm sorry. It's the television? Oh, I love that show. Hold on, let's see the right answer.

The WHO guidelines cite sleep disturbance, annoyance and communication interference as critical effects of hospital noise. The sequelae of these effects can be serious. Sleep disturbance alone leads to delirium and subsequent increases in hospital stay, morbidity and mortality (Crit Care. 2009;13(2):208). In addition, noise-induced occupational stress has been linked to burnout in critical care nurses (Heart Lung. 1988;18(5):567-74).

Good morning, Ms. Earshot. How are you today? Did you sleep well overnight? So you can't hear me at the moment because you don't have your hearing aid in? And you took it out so you could get some peace and quiet? I envy you, Ms. Earshot. I wish I could just turn off all that whizzing and whirring. That banging is the new ward they are building. It will house a sleep lab. Yes, your roommate does appear to snore quite loudly.

The great irony of hospital noise is that we overcome it by creating more noise. What do patients do if they cannot hear their televisions? They turn the volume up. What do we do if we cannot hear another health professional? We talk louder. Even one of the most effective interventions for reducing the effects of noise—sound masking—involves covering up existing sounds with more sounds. These vicious cycles do little to ameliorate the rackets in hospitals.

Behavioral modification and acoustic absorption (using foam to absorb sound) reduce noise effectively (Crit Care. 2009;13(2):208) and probably represent the future in turning the volume knob down. Earplugs help in preventing the effects of sound, but like sound masking, they miss the point in actually decreasing sound. Complicating the entire issue is a generation raised on thumping bass and earbuds. Will future generations of physicians all be wearing hearing aids?

Hang on, Ms. Earshot, I am trying to hear that murmur. Call a code! Wait, I can feel a pulse, I just can't hear any heartbeats. Yes, Ms. Earshot, you do appear to be quite alive. Excuse me, madam, can you turn down your television? I'm trying to establish your roommate's code status. Oh yes, that is quite a good show.

Ms. Earshot, if you need anything, just call for the nurse. But use the call button.