You are visiting a website that is not intended for your region

The page or information you have requested is intended for an audience outside the United States. By continuing to browse you confirm that you are a non-US resident requesting access to this page or information.

Switch to the US site

COVID-19 Resource Center

Healthcare professionals can find help and guidance on how to benefit from our offerings to treat your patients, as well as other practical information and advice.

Read more

Brighter lighting

Brighter lighting isn’t necessarily better

 

Topics

Brighter lighting isn’t necessarily better

A correlation exists between reduced visual fatigue and diagnostic accuracy
[1], performance[2] and safety[3]. These visual problems can place surgeons and their patients at risk[4].

Mitigating the impact of visual fatigue in the OR

Most people have experienced the symptoms of visual fatigue: eyes that feel sore, itchy, or dry. Sometimes our bodies compensate by producing excess tears, causing visual impairment.

But eye strain can also spark a cascade of full-body fatigue. In poor visual conditions, human posture becomes strained. We see this every day in the rounded shoulders and forward lean of laptop and mobile phone users. The postural changes caused by visual fatigue can cause up to three times as much musculoskeletal strain. [4] This poor posture leads to overall bodily fatigue, which is correlated with increased errors.[2],[3],[5]

Measuring the impact of visual fatigue

In 2015, Dr. Patrice Peyrat, a general surgeon at Léon Bérard Cancer Center (CLB) in Lyon, France, began to study ways to minimize the impact of visual fatigue in the OR.

Was brighter lighting the answer, or did the solution require better lighting? He began by speaking with Jean-Pierre Breysse, Senior Director Strategic Office, Marketing/Product Management at Getinge, who was interested in exploring how the LMD function of the PowerLED lighting family improved visual comfort.

Our knowledge on the topic was limited. We needed to involve vision professionals.

What is visual fatigue, and how could it be evaluated?

The first step was to understand the notion of visual fatigue: what was it, and how could it be evaluated? 

“Our knowledge on the topic was limited,” said Dr. Peyrat. “We needed to involve vision professionals.” He contacted the Lyon School of Orthoptics at Claude Bernard Lyon 1 University and established a collaboration between the school and CLB. Orthoptics students contributed their thoughts and knowledge over a period of three years, culminating in a final thesis; Dr. Peyrat supervised their internship.

“In 2016… we structured the conditions for carrying out the tests and evaluating their relevance,” Dr. Peyrat explains. Study participants would be measured before and immediately after laparotomy procedures lasting at least three hours. 

The series of tests took about 10 minutes, and included:

  • A Serret test to identify contrast sensitivity
  • Using a Maddox wing to measure phoria (eye misalignment), a test of oculomotor muscles
  • Conducting a prism vergence test using a Berens prism bar to evaluate ocular misalignment
  • Punctum proximum accommodation (PPA) under divergence or convergence
  • An accommodative rock test, where the subject alternates between near and distance vision to measure ability of the eye to quickly focus and refocus

Subjects were observed under three different conditions: low intensity lighting, medium intensity lighting, and high intensity lighting. A significant difference was found between the tested subjects and the controls for both PPA and prism vergence.

The results were published in a poster at the Congrès de l’Association Française de Chirurgie (French Surgery Association Congress) in September 2018.

Brighter isn’t better for avoiding visual fatigue

Dr. Peyrat and his team discovered that visual fatigue could be minimized by limiting the contrasts in luminance that a surgeon experiences during a procedure. Luminance is the light emitted or reflected by the cavity. In surgery, deep tissue and bleeding can appear dark, while reflected surfaces of surgical tools can appear suddenly and brightly. These excessive variations of luminosity impair the surgeon's ability and comfort.

Dr. Peyrat’s team suggests maintaining significant ambient light, and never performing surgery in a dark room. More natural light is better for reducing fatigue.

Ways to reduce visual fatigue

  1. Begin the procedure at the lowest possible illumination setting and gradually increase the intensity as the depth of field deepens and darkens.

  2. Avoid too much focus on the brightest spot of illumination.

  3. Take care when using multiple surgical lights to avoid overexposing the surgical field . The lighting levels of two or more lights are added together to measure intensity.

  4. Minimize strong contrasts between the operating field and the ambient lighting of the room.

More information about surgical lighting

Related articles

  • Operating Room

Patient Positioning in the OR

Proper patient positioning is an important prerequisite for a successful surgical procedure. Optimum positioning not only ensures the best possible access to the surgical site, but prevents the long-term consequences of nerve damage or pressure ulcers.

Read more

  • Operating Room

Road map to Hybrid suite

Optimizing the planning process for designing and commissioning the single-discipline, multidisciplinary and multi-modality Hybrid OR.

Read more

  • Operating Room

Ventilation performance

If all perioperative organ injuries were grouped, they would be the third leading cause of death in the USA. Prevention of organ injury, such as lung damage, could reduce the need for postoperative escalation of care. Learn more about how lung protective ventilation can participate to reduce health-related complications and costs.

Read more

  • Operating Room

Why low-flow anesthesia?

Low-flow anesthesia offers pulmonary, economic and environmental benefits.

Read more

  • Operating Room

Basics of surgical lighting

The right surgical lighting is critical for patient safety and staff comfort. It should be designed to enable the medical team to focus exclusively on the surgical operation.

Read more

  • Operating Room

Reducing visual fatigue in the OR

Reducing contrast between the surgical site and surrounding areas improve comfort and visual performance. The most effective surgical lighting will provide a gradual transition between the illuminated area and the operating room lighting to reduce eyestrain.

Read more

All references

  1. Hemphälä H, Johansson G, Odenrick P, Åkerman K, Larsson PA. Lighting Recommendations in Operating Theatres. Proceedings of the 17th World Congress on Ergonomics 2009. 2009.

  2. Kato Y, Endo H, Kizuka T. Mental fatigue and impaired response processes: event-related brain potentials in a Go/NoGo task. Int J Psychophysiol. 2009 May;72(2):204-11.

  3. Patterson PD, et al. Association between poor sleep, fatigue, and safety outcomes in emergency medical services providers. Prehosp Emerg Care. 2012 Jan-Mar;16(1):86-97.

  4. Hemphälä H, Johansson G, Odenrick P, Åkerman K, Larsson PA. Lighting Recommendations in Operating Theatres. Proceedings of the 17th World Congress on Ergonomics 2009. 2009.

  5. Barker LM, Nussbaum MA. Fatigue, performance and the work environment: a survey of registered nurses. J Adv Nurs. 2011 Jun;67(6):1370-82.