can baby overheat in sleep sack

Can Baby Overheat In Sleep Sack?

Luckily, there’s an easy way to tell if your baby is too hot. Touch her ears and neck. If her ears are red and hot and her neck is sweaty, your baby is too warm. Dress her more lightly or cool the room.

Parents want to make sure their babies are cozy at night. Sleep is essential to a newborn’s development--and a parent’s sanity! Although it isn’t always easy to know whether or not your newborn is safe and comfy when you put them to bed.

In the warmer months, parents also face the added challenge of asking themselves, “Am I overheating the baby at night?”

Often parents worry about their newborns being too cold (which you want to avoid!), but at night, it is critical to be sure a child is not too hot. Going to bed too warm can cause mild side effects, from poor sleep to a heat rash.

A normal temperature is 97.5 degrees Fahrenheit (36.4 degrees Celsius) for infants. Around 100.4 degrees Fahrenheit (or 38 degrees Celsius) is considered too hot for a baby.

Little ones are not born able to regulate their temperature. This not only makes them more prone to overheating but also to getting too cold. They lose body heat four times faster than adults or older children!

When their body temperature rapidly changes, they are unable to communicate properly or make the necessary adjustments such as:

  • Shiver to indicate they are cold
  • Remove clothing to indicate they are hot
  • Excessive sweating to indicate they are hot

During the warm summer months and even into the fall, parents in Texas and California struggle to keep their babies cool at night. Parents and guardians need to arm themselves with the right knowledge and tools to keep their little ones comfy yet safe when they go to bed. This involves knowing what to look for when it comes to overheating.

Here are some indicators a baby is too hot:

  • Warm to the touch
  • Flushed or red skin
  • Rapid heartbeat
  • Fast breathing
  • Vomiting
  • Lethargic or unresponsive
  • Sweaty neck or damp hair
  • Heat rash
  • Restless and unable to sleep
  • Rectal temperature of 100.4 or higher

If you’re concerned that your little one has overheated, staying calm is important!

Here are some ways to help bring their temperature safely back down:

  • Offer fluids (breastmilk, formula, or sips of water depending on their age)
  • Apply a cold compress to their forehead or limbs
  • Could you give them a lukewarm (NOT cold) bath?
  • Take off layers of clothing
  • Go to a well-ventilated room.

If your child is unresponsive, call 911 or immediately proceed to the nearest emergency room.

Making sure your baby is at the right temperature at night makes for a better night of sleep for them and you! Parents can take several preventive measures to avoid overheating their baby at bedtime.

FAQs About Baby Sleep

Parents have several options for dressing their baby. This includes a short sleeve onesie, a long sleeve onesie, or footie pyjamas. When checking your baby's temperature, their tummy and chest should feel warm and dry, not sweaty or cold.

Won't my baby's arms and hands get cold? Bags are generally designed without arms as it helps to ensure your baby doesn't overheat. The arms and head are the main ways babies release heat to avoid overheating. As long as your baby's core is warm, you don't need to worry about cooler arms and cold hands.

Won't my baby get cold? Baby Blankets don't have sleeves either! The armholes allow for free circulation of airflow- something essential to prevent the dangerous overheating of your baby.

"It is important we make sure the baby doesn't get too hot or too cold for safe sleep without increased risk of SIDS. "A bedroom temperature of 16-20 degrees is ideal, but in a heatwave, we are getting temperatures of up to 28 degrees."

It is most common to use a onesie, footie, romper, or two-piece pyjama sets under a baby sleep sack. Usually, one layer of clothing under the appropriate TOG of the sleep sack is sufficient!

The One Thing You Need To Know About Sleep Sacks

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If you're a parent, you may get overwhelmed by the sheer amount of information on sleep safety. But, of course, great information is available, but what do you do when reliable sources contradict themselves? 

As parents wrestle with all the ways to help their baby sleep, it's common for most to consider a sleep sack as a safe alternative to crib bumpers. But can a baby get overheated in a sleep sack? After all, alternatives are great until they start presenting potential problems.

Parents should make sure that babies don't "get too hot" when sleeping, and keeping the room at a "comfortable temperature" helps reduce the risk of Sudden Infant Death Syndrome (SIDS). 

But what is "too hot", and how do parents measure the undeniably subjective instruction of a "comfortable temperature"?

The AAP tells us parents that babies should never wear more than one additional layer than they feel comfortable wearing for the specific room temperature. When talking about protecting babies in extreme heat, tells us to look out for signs of overheating, including "being very warm to the touch (more than how your baby's typically-warm belly feels), extreme thirst, sweating profusely, acting very tired or weak and showing a general lack of energy." If you see any of those signs, it's safe to assume your baby is in danger of, or already, overheating.

Now that the signs of overheating and other red flags to look out for have been highlighted, it's worthwhile to ask oneself if there are any reports of babies overheating in a sleep sack. 

One brand site claims that babies are kept from overheating by the sleeveless arms of the sleep sack and the ability for parents to adjust what the baby wears under the sack depending on the room temperature. 

In other words, if it's hot in the baby's bedroom, don't use the fleece sleep sack and let the baby wear a diaper, and a diaper only, under the sleep sack itself.

There doesn't appear to be any hard and fast rule about overheating in a sleep sack. Using "a wearable blanket" is casually included in the AAP safe sleep guidelines as a safe sleep option. 

So, like any other article of clothing for a baby, parents should use common sense and follow general safety guidelines when laying their baby down to sleep and taking a nap, like a diaper above only option to prevent your baby from overheating.

Signs of Overheating

Below you'll find a few signs and symptoms of a baby overheating:

  • They feel warm to the touch
  • Your baby's skin is red
  • They have a rapid heartbeat
  • They have a fever but aren't sweating
  • Your baby is lethargic or unresponsive
  • Your baby is vomiting
  • Your baby seems dizzy or confused

Clammy Skin

You can tell if your baby is too hot if their neck, back or tummy is sweaty or warm to the touch. Avoid the 'touch test' on a baby's hands and feet, as these will usually feel colder than the rest of their body and give an inaccurate body temperature. If in doubt, use a thermometer – the normal body temperature for a baby is between 36 and 37°C.

Red Face and Rashes

If your baby's skin is red or blotchy, this is also an overheating indicator. When a baby gets too hot, sweat can irritate the hair follicles in their skin and present as a prickly rash or red splotches. Rashes usually appear in areas with skin-to-skin contacts, such as armpits, elbows, thighs, or areas flat against fabrics, such as the neck, chest, and back. Our guide to creating a baby's heat rash has several tips for soothing babies with heat rash.

Rapid Breathing and Raised Heart Rate

Your baby's breathing might quicken when they're too hot because their body is working extra hard to cool itself down. This process usually happens when your baby has been too warm, so it's important to act quickly if you notice fast breathing or a quickened pulse. 

A newborn younger than six months of age takes about 40 breaths per minute, which can slow down to 20 breaths per minute when sleeping. If your baby is breathing more than 60 times in a minute, seek urgent medical advice.

Lethargic and Disoriented

Of course, your baby will be sleepy when waking up for a feed, but if you notice that they are unusually unresponsive, dizzy, or lethargic, they could be overheated. Check their skin temperature alongside their pulse rate and remove a layer of clothing or bedding to see if this helps them settle.

Increased Irritability

Another sign your baby is too hot while sleeping is restlessness and irritability. It could be that your baby is teething, but this could also be a warning sign that they are overheating.

If your baby presents with any of these signs during sleeping, attempts must be made to cool them down. To prevent your baby from getting too hot or to help them cool down, ensure the room is between 16-20°C using a room thermometer. Many monitors have a thermometer function which can be useful. In addition, remove layers of bedding or clothing, open windows or use a fan as needed to help.

It is fairly common for babies to be warmer during the summer or when wearing a Band, and it is usually easy enough to relieve this. However, if your baby's temperature stays high, it could also indicate that your baby is unwell. If they don't cool down or continue getting warmer, seek professional medical advice immediately.

If your baby is currently undergoing plagiocephaly treatment and is concerned about your baby overheating when wearing their helmet, don't hesitate to contact one of our friendly and experienced clinicians. They will be happy to help you.

Ideal Baby Room Temperature

The room should be kept between 68° F to 72°F 9 (20°C to 22.2°C). You can measure the room temperature with a thermometer, but the temperature should not be too cool or too warm for an adult.

In hot weather, it's totally fine to let your baby sleep in just a diaper and light muslin swaddle. But, of course, you should not overdress your baby or overheat the room, whether she's swaddled.

Hot Baby Means Restless Baby

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If your baby is too warm, she may become restless, leading to less sleep for her… and you! Don't over-bundle your little bundle for naps or at bedtime with extra layers of clothing or hats. 

Hats are especially problematic because covering the head reduces the baby's ability to use the head as a little radiator, giving off extra heat. Also, in the middle of the night, a hat might accidentally slip over your little one's face and cause breathing difficulties. 

Never use blankets (a safe crib free of toys, blankets and all objects except a pacifier) and never use electric blankets or heating pads under your baby. These overheat infants and expose them to electromagnetic radiation.

How Do You Cool Down an Overheated Baby

If you believe your baby is overheating, then here are some steps that you can try to cool down your baby.

  • Offer your baby fluids
  • Take your baby to a cooler room
  • Dress your baby in light clothing
  • Sponge your baby in lukewarm/cooler water
  • If symptoms do not improve, then contact your pediatrician

Baby Overheating & Heat Rash

Babies develop heat rash when their salty sweat irritates the skin. It most commonly appears on their necks, armpits, chest, back, elbows or thighs. The rash presents as little red dots (irritated hair follicles) and splotchy skin and can be accompanied by fever, chills and bumps. 

If you think your child has a heat rash, give your doctor a call. She may recommend sprinkling on a dusting of cornstarch powder—never talcum—to absorb excess sweat and prevent irritation.

Newborn Overheating vs. Fever

It's natural to think that your overheated baby may have a fever. Take your baby's temperature and consult your healthcare provider if you have any concerns. Additionally, the symptoms below are indicators that your baby may have a fever:

  • Difficulty sleeping
  • Lack of eating
  • No interest in playtime
  • Lethargic or not as active as usual

Protecting Baby From Overheating During Sleep

It is unnecessary to monitor the room temperature or leave the heating or cooling on all night, as long as the baby is dressed appropriately for the room temperature: Dress baby as you would dress yourself – comfortably warm, not hot or cold. 

A good way to check a baby's temperature is to feel the baby's back or tummy, which should feel warm (don't worry if the baby's hands and feet feel cool, this is normal).

A good way to avoid face covering is to use a safe baby sleeping bag (one with a fitted neck, armholes or sleeves and no hood). 

If using bedclothes rather than a sleeping bag, it is best to use layers of lightweight blankets that can be added or removed easily according to the room temperature and which can be firmly tucked in. 

The bed should always be made up so that the baby is at the foot of the cot so the blanket can only rise as far as the baby's chest.

Remove the baby's bonnet, beanie or hat as soon as you go indoors or enter a warm car, bus or train, even if it means waking the baby.

  • Never use electric blankets, wheat bags, heat packs or hot water bottles for babies.
  • Never leave the baby in a car to sleep while unsupervised

Sleep Sack Safety

Infant sleep sacks are like a cross between a dress and a blanket. They start like a sleeveless shirt on the top and flow out like a dress at the bottom but are completely enclosed.

They zip up the front, creating a cozy sleeping bag for the baby. 

Infant sleep sacks improve sleep safety for newborns by reducing the risk of sudden infant death syndrome. Still, parents must use them properly to avoid other risks, such as overheating or choking on the zipper.

Suffocation and SIDS

Babies need to stay warm while sleeping, but blankets and other loose bedding can increase the risk of suffocation and SIDS.

Sleepsacks keep babies warm without the risk that the fabric could cover their faces or bunch up around their airways, making it harder to breathe. Breathing difficulties are one of the causes of SIDS, and sleep sacks may help to reduce the risk.

Concerns about Overheating

Overheating is another risk factor for SIDS. Blankets and sleep sacks can lead to overheating if not used properly. Many sleep sacks are made of fleece or polyester to keep babies warm. 

Parents should dress their babies lightly under the sleep sack, depending on the temperature in the room. For example, parents may need to dress their babies in light pyjamas when it's very warm inside and choose a lightweight sleep sack.

Zippers and Embellishments

Some components of sleep sacks have been reported to cause injuries or to pose a choking hazard.

Some parents reported that the zipper on the Sleepsack caught in their babies' teeth, leading to injury.

Others reported that the zipper broke apart into several pieces, which could have been a choking hazard had the zipper been in the baby's mouth when it happened.

The Consumer Product Safety Commission recalled some models of the HALO SleepSack with pink satin flower embellishments since they posed a choking hazard. 

When selecting a sleep sack, look for designs free of embellishments and Velcro coverings over the zipper or another type of enclosure.

Benefits of Sleep Sacks

Swaddling helps many newborns feel snug and secure, helping them sleep better. However, as babies grow, they may become resistant to being swaddled. Some parents say that a sleep sack helps their baby to feel secure while also giving him a little more room to move his arms and legs.

Sleepsacks can help these babies sleep better at night and ease the transition away from swaddling. Sleepsacks also help keep babies warm throughout the night, unlike a blanket, which may be kicked off or wrapped around a baby's legs or midsection.

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