Extreme heat is increasingly common in Australia and around the world and besides making us uncomfortable, it can harm our health. For example, exposure to extreme heat can exacerbate existing medical conditions, or cause problems such as heat stroke.

Due to a combination of physiology and behaviour, children are potentially more vulnerable to severe heat-related illness such as heat stroke or heat exhaustion.

But these are not the only heat-related health issues children might experience on a very hot day. In a new study, we looked at emergency department (ED) visits and unplanned hospital admissions among children in New South Wales on heatwave days.

We found a significant increase in children attending hospital compared to milder days – with a range of health issues.

Why are children more vulnerable in the heat?

Sweating is the main way we lose heat from our bodies and cool down.

Children have a greater skin surface area to body mass ratio, which can be an advantage for sweating – they can lose more heat through evaporation for a given body mass. But this also means children can lose fluids and electrolytes faster through sweating, theoretically making them more susceptible to dehydration.

Meanwhile, younger children, particularly babies, can’t sweat as much as older children and adults. This means they can’t cool down as effectively.

Children in general also tend to engage in more outdoor physical activity, which might see them more exposed to very hot temperatures.

Further, children may be less in-tune to the signals their body is giving them that they’re overheating, such as excessive sweating or red skin. So they might not stop and cool down when they need to. Young children especially may not recognise the early signs of heat stress or be able to express discomfort.

Our study

We wanted to examine children’s exposure to extreme heat stress and the associated risks to their health.

We measured extreme heat as “heatwave days”, at least two consecutive days with a daily maximum temperature above the 95th percentile for the relevant area on a universal thermal climate index. This ranged from 27°C to 45°C depending on the area.

We assessed health outcomes by looking at ED visits and unplanned hospital admissions among children aged 0–18 years from NSW between 2000 and 2020. This totalled around 8.2 million ED visits and 1.4 million hospital admissions.

We found hospital admissions for heat-related illness were 104% more likely on heatwave days compared to non-heatwave days, and ED visits were 78% more likely. Heat-related illness includes a spectrum of disorders from minor conditions such as dehydration to life-threatening conditions such as heat stroke.

But heat-related illness wasn’t the only condition that increased on heatwave days. There was also an increase in childhood infections, particularly infectious enteritis possibly related to food poisoning (up 6% for ED visits and 17% for hospital admissions), ear infections (up 30% for ED visits and 3% for hospital admissions), and skin and soft tissue infections (up 6% for ED visits and 4% for hospital admissions).

We know many infectious diseases are highly seasonal. Some, like the flu, peak in winter. But heat and humidity increase the risk of certain infections caused by bacterial, viral and fungal pathogens.

For example, warmer weather and higher humidity can increase the survival of bacteria, such as Salmonella, on foods, which increases the risk of food poisoning.

Hot weather can also increase the risk of ear infections. Children may be at greater risk during hot weather because they often swim or play at the beach or pool. Water can stay in the ear after swimming and a moist environment in the ear canal can cause growth of pathogens leading to ear infections.

Which children are most vulnerable?

During heatwaves, we found infants aged under one were at increased risk of ED visits and hospital admission for any reason compared to older children. This is not surprising, because babies can’t regulate their body temperature effectively and are reliant on their caregivers to keep them cool.

Our study also found children from the most disadvantaged areas were more vulnerable to heat-related illness on heatwave days. Although we don’t know exactly why, we hypothesised families from poorer areas might have limited access to air-conditioning and could be more likely to live in hotter neighbourhoods.

Keeping kids cool: tips for parents

The highest levels of heat exposure on hot days for young children is usually when they’re taken outside in prams and strollers. To protect their children from direct sunlight, parents often instinctively cover their stroller with a cloth such as a muslin.

However, a recent study from our group showed this actually increases temperatures inside a stroller to as much as 3–4˚C higher than outside.

But if the cloth is wet with water, and a small fan is used to circulate the air close to the child, stroller temperatures can be 4–5˚C lower than outside. Wetting the cloth every 15–20 minutes (for example, with a spray bottle) maintains the cooling effect.

When young children are not in a stroller, and for older children, there are a few things to consider to keep them cool and safe.

Remember temperatures reported on weather forecasts are measured in the shade, and temperatures in the sun can be up to 15˚C higher. So sticking to the shade as much as possible is important.

Exercise generates heat inside the body, so activities should be shortened, or rescheduled to cooler times of the day.

Sunscreen and hats are important when outdoors, but neither are especially effective for keeping cool. Spraying water on the child’s skin – not just the face but arms, legs and even the torso if possible – can help. Wetting their hats is another idea.

Proper hydration on hot days is also essential. Regular water breaks, including offering water before, during and after activity, is important. Offering foods with high water content such as watermelon and orange can help with hydration too.

Wen-Qiang He, Research Fellow in Biostatistics and Epidemiology, Faculty of Medicine and Health, University of Sydney; James Smallcombe, Post-doctoral Research Associate, Faculty of Medicine and Health, University of Sydney; Natasha Nassar, Professor of Paediatric and Perinatal Epidemiology and Chair in Translational Childhood Medicine, University of Sydney, and Ollie Jay, Professor of Heat & Health; Director of Heat & Health Research Incubator; Director of Thermal Ergonomics Laboratory, University of Sydney

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Last week in a post on X, owner of the platform Elon Musk recommended people look into disc replacement if they’re experiencing severe neck or back pain.

According to a biography of the billionaire, he’s had chronic back and neck pain since he tried to “judo throw” a 350-pound sumo wrestler in 2013 at a Japanese-themed party for his 42nd birthday, and blew out a disc at the base of his neck.

In comments following the post, Musk said the surgery was a “gamechanger” and reduced his pain significantly.

Musk’s original post has so far had more than 50 million views and generated controversy. So what is disc replacement surgery and what does the evidence tells us about its benefits and harms?

What’s involved in a disc replacement?

Disc replacement is a type of surgery in which one or more spinal discs (a cushion between the spine bones, also known as vertebrae) are removed and replaced with an artificial disc to retain movement between the vertebrae. Artificial discs are made of metal or a combination of metal and plastic.

Disc replacement may be performed for a number of reasons, including slipped discs in the neck, as appears to be the case for Musk.

Disc replacement is major surgery. It requires general anaesthesia and the operation usually takes 2–4 hours. Most people stay in hospital for 2–7 days. After surgery patients can walk but need to avoid things like strenuous exercise and driving for 3–6 weeks. People may be required to wear a neck collar (following neck surgery) or a back brace (following back surgery) for about 6 weeks.

Costs vary depending on whether you have surgery in the public or private health system, if you have private health insurance, and your level of coverage if you do. In Australia, even if you have health insurance, a disc replacement surgery may leave you more than A$12,000 out of pocket.

Disc replacement surgery is not performed as much as other spinal surgeries (for example, spinal fusion) but its use is increasing.

In New South Wales for example, rates of privately-funded disc replacement increased six-fold from 6.2 per million people in 2010–11 to 38.4 per million in 2019–20.

What are the benefits and harms?

People considering surgery will typically weigh that option against not having surgery. But there has been very little research comparing disc replacement surgery with non-surgical treatments.

Clinical trials are the best way to determine if a treatment is effective. You first want to show that a new treatment is better than doing nothing before you start comparisons with other treatments. For surgical procedures, the next step might be to compare the procedure to non-surgical alternatives.

Unfortunately, these crucial first research steps have largely been skipped for disc replacement surgery for both neck and back pain. As a result, there’s a great deal of uncertainty about the treatment.

There are no clinical trials we know of investigating whether disc replacement is effective for neck pain compared to nothing or compared to non-surgical treatments.

For low back pain, the only clinical trial that has been conducted to our knowledge comparing disc replacement to a non-surgical alternative found disc replacement surgery was slightly more effective than an intensive rehabilitation program after two years and eight years.

Complications are not uncommon, and can include disclocation of the artificial disc, fracture (break) of the artificial disc, and infection.

In the clinical trial mentioned above, 26 of the 77 surgical patients had a complication within two years of follow up, including one person who underwent revision surgery that damaged an artery leading to a leg needing to be amputated. Revision surgery means a re-do to the primary surgery if something needs fixing.

Are there effective alternatives?

The first thing to consider is whether you need surgery. Seeking a second opinion may help you feel more informed about your options.

Many surgeons see disc replacement as an alternative to spinal fusion, and this choice is often presented to patients. Indeed, the research evidence used to support disc replacement mainly comes from studies that compare disc replacement to spinal fusion. These studies show people with neck pain may recover and return to work faster after disc replacement compared to spinal fusion and that people with back pain may get slightly better pain relief with disc replacement than with spinal fusion.

However, spinal fusion is similarly not well supported by evidence comparing it to non-surgical alternatives and, like disc replacement, it’s also expensive and associated with considerable risks of harm.

Fortunately for patients, there are new, non-surgical treatments for neck and back pain that evidence is showing are effective – and are far cheaper than surgery. These include treatments that address both physical and psychological factors that contribute to a person’s pain, such as cognitive functional therapy.

While Musk reported a good immediate outcome with disc replacement surgery, given the evidence – or lack thereof – we advise caution when considering this surgery. And if you’re presented with the choice between disc replacement and spinal fusion, you might want to consider a third alternative: not having surgery at all.

Giovanni E Ferreira, NHMRC Emerging Leader Research Fellow, Institute of Musculoskeletal Health, University of Sydney; Christine Lin, Professor, Institute for Musculoskeletal Health, University of Sydney; Christopher Maher, Professor, Sydney School of Public Health, University of Sydney; Ian Harris, Professor of Orthopaedic Surgery, UNSW Sydney, and Joshua Zadro, NHMRC Emerging Leader Research Fellow, University of Sydney

This article is republished from The Conversation under a Creative Commons license. Read the original article.