Industry experts share 6 best practices for applying and managing electrodes and sensors during in-lab sleep studies.

By Lisa Spear

Every sleep technologist knows that getting sleep sensors to hold fast throughout the night and deliver strong signals is of the utmost importance, but the number of challenging scenarios that sleep techs may encounter in the lab may seem endless—an anxious child who can’t stop pulling on the EEG leads, an obese patient who sweats so profusely that the waveforms are disrupted, or even a patient wearing a toupee that makes it more challenging to place electrodes.

Thankfully, with some simple preparation and foresight, sleep techs can prevent the most common sensor malfunctions before they occur while also preparing for unforeseen circumstances. 

Sleep Review spoke to sleep technologists and other industry experts to gather real-life examples of how to get the best possible sleep study data. Here’s a list of the top tips and tricks for keeping electrodes and sensors stable and secure, while making sure that the patient is comfortable throughout the night. 

1. Conductive Paste is Your Friend

Most sleep techs we spoke to highlighted the importance of applying a small amount of conductive paste to the scalp to increase the hold and optimize the EEG signals.

A sleep tech at Memorial Hermann Health System in Texas, Dmitry Spektor, RPSGT, CCSH, says he uses “flower petal-like” motions to apply the paste with his fingers, pressing away from a central spot where the electrode will be placed. “Move away from the middle out, just to get all the hair out of the way and create good contact with the scalp,” he says.  

A sleep tech who has over a decade of experience working in sleep labs and now works as a clinical informaticist with sleep scoring software company EnsoData, Shahnawaz Khan, RPSGT, CCSH, says the paste also works as a makeshift placeholder to guide the technologist to the correct spot on the patient’s scalp. 

At United Hospital’s sleep center in St. Paul, Minnesota, sleep tech Celine Burns, RPSGT, who has worked in the sleep field in the Midwest for 26 years, says in addition to putting the paste under the electrode cups, she also uses paste to secure a small gauze square over each electrode, a technique that she’s found leads to a stronger hold.

2. Mind Your Wires

A common issue when conducting an in-lab sleep study is EEG leads that pull too much on the patient’s scalp when the patient is moving during the night. 

Many sleep technologists recommend guiding the EEG wires up and gathering them at the top of the head, so the patient is free to move around during sleep. 

“If you have all the wires pushing down toward the bottom right, all it takes is one simple movement to the left or right for the electrodes to fall off,” says Khan.

“So, by pushing them all the way up, basically to the center of the top of the head, you can basically set up a ponytail with a piece of paper tape to create multiple points of tension. So when the patient moves to the left or right, the electrodes simply swivel, and they don’t pull.” 

Sleep tech at United Hospital in Minnesota, Burns says it is important to take the stress off the leads as much as possible. “Definitely try to leave some extra room for movement, so they are not too tight, and not as likely to pull off,” she says.

When working with young children who might try to rip the wires out of place, Khan recommends using a net cap to keep the electrodes in place. Then the tech can gather the electrodes and put them under the pillow, so the child doesn’t see them as much, he says. 

“The less that is shown to the pediatric patient, the better for your chances of minimizing them removing the wires at night,” he says. 

3. Preparation Pays Off

Advanced preparation can save time in the long run. Before a patient even arrives, Khan prepares his tray with all the necessary pieces of tape and gauze. He counts all his electrodes and separates them into categories. 

“I make sure that everything is perfect ahead of time,” he says. “I have everything ready to go, so if something were to happen, it doesn’t affect my ability to finish on time.”

Once you have an established prep system, you can save time by streamlining the process and preparing for unforeseen scenarios that might require more time, including a patient who is wheelchair-bound or a patient experiencing a mental health issue. 

4. Tighter Sensors Are Not Better

When fitting a patient with a respiratory effort belt, make sure that the belt is snug, but not overly tight. “I see a lot of issues where a tech will get the belts too tight and that’s detrimental in two ways. Number one: it’s uncomfortable for the patients. Number two: if you overtighten the belt, it can’t stretch and you won’t get a waveform,” says Spektor. 

The best way to get a good belt sensor fit? Ask the patient for their feedback about how the sensor feels. Ultimately, Spektor says, the patient is the only one who can tell you if the sensor is tight or not. 

With certain patients, Khan says after attaching all the electrodes and sensors, he confirms that the patient still has an appropriate range of movement. 

“I have them extend their arm out if they have the SpO2 on. I have them look left and right and completely swivel their head back and forth and up and down to make sure that there is nothing tugging. I make sure that they are basically able to move exactly how they would need to in their sleep without the wire pulling on them,” he says.

Khan suggests that all sleep techs should get a sleep study at part of their training. “Until you literally have had all those wires on you, you do not understand.” 

A lot of times, the sleep techs might put the pulse oximeter on too tight without realizing it. By trying on the pulse oximeter and other sensors themselves, sleep techs can gain a level of physical empathy for their patients. 

“I think it is very important to understand what it feels like,” Khan says. 

5. Pay Attention to Patient Comfort

Many techs will agree that ensuring patient comfort is an essential part of gathering the most accurate sleep study data. Optimizing comfort starts with communicating and trying to understand each patient’s individual needs. For instance, when working with children, give them a sense of autonomy by allowing them to touch and hold the sensors before they are placed, explains Khan.

For obese patients, temperature control might be especially important not just for comfort, but also to reduce the sleep sensor artifact that can come as a result of sweating. By ventilating the room and keeping a fan available, the sleep study results can be more accurate.  

One of the most common issues that sleep techs face is moisture from sweat jeopardizing the integrity of the sleep study waveform, says Todd Eiken, RPSGT, vice president of product development at the sleep sensor company Dymedix Diagnostics.

Thankfully, there are ways to cope with a sweaty patient. “I’ve placed a towel under the patient’s head to try to absorb sweat,” says Burns. A towel roll under the patient’s head could also prevent movement during the night. 

And don’t be shy about using the air conditioner if it is available. A sleep tech at Memorial Hermann Health System in Texas, Spektor, says that overall, it’s easier to give someone a blanket rather than cool off somebody once they are hot. 

“I would always err on the side of keeping it a little cooler in the sleep lab,” he says.

6. Communication Goes a Long Way

As a last resort, in circumstances of mental illness or other conditions that might make it challenging to attach sleep sensors, some techs suggest  attaching electrodes once a patient is asleep. 

But Khan says communicating with a patient to help them understand the sleep study process is always better than trying to attach sensors to a person when they are sleeping. 

Ask your patients how the sensors feel to them and adjust accordingly, he explains.  And stress that you are there to make sure the patient has as much of a comfortable night’s sleep as possible.

Lisa Spear is associate editor of Sleep Review

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