Have you thought about this? About the detrimental effects of prolonged bed rest? This post is about that.
A little bit of history about bed rest research
Researchers say that bed rest was considered as a treatment strategy in the 19th century. This view was beginning to change at the turning to the 20th century.
In 1947, Dr. R.A.J. Asher wrote an article to the British Medical Journal about “Dangers of going to bed”. His article was meant for physicians: ” we should think twice before ordering our patients to bed and realize that beneath the comfort of blanket there lurks a host of formidable dangers”.
Since then, more evidence has been accumulating. In 1999, a group of researchers reviewed 39-bed rest trials published in The Lancet. The conclusion: bed rest did not improve the outcome significantly; rather they reported nine situations with worsening outcomes.
However, the campaign is ongoing. For example, if you visit the website of the American Academy of Nursing, you can read the “Don’t Statement”:
In fact, The problem has received attention from several countries. It has led to a campaign named, “End PJ paralysis”.
End PJ (Pyjama) paralysis
End PJ paralysis is a global movement: https://endpjparalysis.org/
The following is a poster that is aimed at addressing this problem. We can find a series of similar educational tools to reduce the detrimental effects of prolonged bed rest.
Let us dive into our bodies to find out what happens when we take prolonged bed rest.
What happens inside our body during a prolonged bed rest?
All our body mechanisms are set to function best when standing upright – and, to sleep only about eight hours. If we prolong our bed rest time for more than 24 hours, the body begins to re-set all the systems to face the new challenges. Certainly, it will. And, it will result in a series of detrimental effects of prolonged bed rest.
Let us jump into this journey of exploring the “detrimental effects of prolonged bed rest”.
Prolonged bed rest’s detrimental effects on the heart and our blood circulation
In an upright position, most of our blood circulates below the heart level. Veins bring up the returning blood with all waste products produced by cells including carbon dioxide. The valves in veins and muscles support veins to do the job.
In contrast, in a lying down position, blood slowly moves to the abdomen, lower back, and lungs from the legs. The new situation exerts pressure on the heart. To relieve the pressure, the body initiates mechanisms to remove a certain amount of water from our blood through kidneys. The aim is to reduce the burden – preload – on heart output. Not only that, but the prolonged bed rest also reduces red blood cell mass too to reduce our blood’s oxygen-carrying capacity.
If the bed rest continues as long as 6 weeks, research has shown that the heart muscles can get atrophied. If the bed rest continues for 20 days, the heart output can reduce by 25 percent according to Kristin J. Stumpfle and Daniel G. Drury.
These adjustments cause problems; one is to increase the resting heart rate; another is the postural hypotension in which we feel dizzy when we attempt to either sit on the bed or stand. It can occur even after 24 hours of strict bed rest.
Another interesting adjustment occurs in our venous blood collection system. It begins to pool blood at our deep veins. As a result, the risk of developing blood clots increases leading to deep vein thrombosis. And, the formed blood clots can dislodge, travel all the way up to lungs, and stuck there. This can result in pulmonary embolism, always a fatal situation.
Prolonged bed rest’s detrimental effects on our muscles
Very much similar to the heart and blood circulation mechanism, our muscles also work best when we stand upright against gravity. In a prolonged bed rest, with time, they begin to shorten and then remove some of its muscle fibers. It invariably loses muscle mass and subsequently its strength. Research shows that we can lose muscle strength by 6 – 40 percent within 4 – 6 weeks of complete bed rest. More recently, a group of researchers from Johns Hopkins found that each passing day in the ICU lowers muscle strength by 3- 11 percent a day over the ensuing months and may even extend to years.
As expected the most affected muscles are the ones that work against gravity”: The “anti-gravity” muscles. Those are the muscles that help to raise the foot at the ankle joint (plantar flexors), those in the thighs and arms (quadriceps and hamstrings), those in the buttocks, calves, lower back, abdomen, and the neck. In some muscles such as those in calves, thighs, and feet, we can readily see the wasting; however, in other muscles, we cannot readily see. Research shows that the process of wasting begins as early as on the fifth day and reaches its peak in the second week of bed rest.
Effects on joints
Muscles are attached to joints through tendons and ligaments. And, joints are covered by some cartilage. Because of non-use, fibers in tendons and ligaments become shortened. Surrounding connecting tissues turn rigid due to the addition of collagen. The result? the development of almost permanent contractures that freeze joint movements. Research shows that the appearance of collagen fiber can be observed as early as on the sixth day of complete bed rest.
These changes occur in all joints. But, it is most pronounced in the hip, knee, and ankle joints.
Effects on bones
As in every part of our body, bones also respond negatively to bed rest. It begins to weaken with time; its building block – calcium – starts appearing in our urine within a few days of bed rest. It also increases the risk of forming kidney stones and urine infections. To make matters worse, calcium absorption in the intestine also decreases.
Research reveals that the bones in our legs and lower back are the worst affected.
Effects on the kidneys and bladder
Due to non-use of bones, its building block, calcium, beings to drain into urine. During the process, the chances of forming stones inside kidneys and the bladder rises. Furthermore, due to urine rentioninside the bladder the chances of urine infection als rises.
Effects on the skin
The effects of prolonged bed rest on the skin particularly the skin over bony prominence are two-fold; shear and friction damage the superficial parts of the skin while the pressure interrupts the deep tissue functions. It includes underlying muscles too.
Prolonged bed rest due to the pressure it exerts on the skin over bony prominences occludes the smallest blood carriers – capillaries – blocking the blood supply to the skin and its surrounding tissues. This sudden attack deprives living cells of oxygen and nutrient supply. The situation will lead to cell death.
Experts say that the critical duration of pressure that requires developing a pressure injury can vary from 30 minutes to 4 hours. This variation depends on underlying diseases that affect small blood supply vessels including the smallest – capillaries.
Shearing, in addition to the direct external pressure, contributes to skin damage. Shearing refers to lateral displacement of the skin due to traction over the surface. Moreover, moisture too worsens the situation by softening the skin layers.
Not only the external pressure, but shearing and friction on the skin damage the skin also. It deprives the skin cells and underlying tissues of its oxygen and nutrition for their survival, It can result in devastating bedsore. Once the process sets in, it can become a slippery slope. The most common 5 sites that pressure ulcers occur are the heel, ankle, bony prominences over the sides of the hip, sacral area, and skin over the sitting bones in the buttocks.
In fact, the detrimental effects of prolonged bed rest manifest all over the body.
Are you doing only the muscle strength exercises? The evidence suggests you change it a little bit: blend cardio into it. Researchers have concluded that cardio with strength training exercises yields better walking ability, walking speed, and body balance (to a certain extent).
And, they also have concluded that muscle strength exercises alone do not improve walking ability.
The emphasis on cardio is a recent finding; traditionally, the rehab programs have been focused on gait training and balance.
This emphasis on cardio is because many who survive the stroke live with low levels of heart fitness; and, it could also be due to that those with low heart fitness are more likely to face a stroke.
What are the suitable cardio exercises?
Walking and cycling are the two commonest cardio exercises. The cardio strengthens the heart. That is why it is called cardio. However, prior to engaging in cardio, the physician should assess the heart fitness and the physiotherapist should recommend the types of cardio that need to follow. The Heart and Stroke Foundation has published an excellent patient guide. You can access this brochure through this link.
What are muscle fitness exercises ? (resistance or strength training)
Some common examples of muscle fitness include pushing, pulling with elastic bands, and lifting weights. In these types of exercises, we do not exert pressure on the heart as much as in walking and cycling.
Range of motions and body balance exercises
Invariably, when we engage in the above two types of exercises, we certainly involve our joints with different types of range of motions and exercises that improve body balance.
About the research
In 2015, David Saunders and his team reviewed 58 clinical trials that compared people with a stroke and engaged in special exercise sessions with a similar group of people who followed usual care. The total number of study participants involved in all these trials was 2797.
In this study, they classified physical fitness into three groups: heart fitness (endurance) training, muscle fitness (strength) training, and mixed training (a combination of the above two forms).
You can access the article through this link; https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6464717/
Do you have any comments, ideas, or suggestions about how to blend cardio with strength exercises? Please initiate a discussion about it.
A guideline resource for exercise providers
The Ontario Stroke Network provides a useful guideline for community-based exercise providers; here is the link.
In June 2020, The Lancet Neurology published a very important Declaration proclaimed by the World Stroke Organization (WSO) on stroke and dementia.
The WSO predicts that by 2050, about 200 million stroke survivors will be in the world. And because of the close link between stroke and dementia, we could expect about 106 million living with dementia; and, thereafter, each year, we may encounter over 30 million new stroke patients.
The most notable statement, to me, in their declaration, is this:
Rather than finding why they say this, I focus my attention on what they propose to do.
Let us find out what they have to say about this.
First of all, it is worthwhile to note that they recommend a common prevention strategy for both stroke and dementia because both problems share the same risk factors.
And, these risk factors contribute not only to stroke and dementia but other leading non-communicable diseases also.
What are those?
- Elevated blood pressure
- Abnormal blood lipid levels
- Physical inactivity
- Salt and sugar
- Unhealthy diet
As we can see that the above risk factors fall into two broad categories;
- Biological (elevated blood pressure and abnormal lipid levels)
- Behavioral or lifestyle; however, behavioral risk factors in turn contribute to elevated blood pressure and abnormal lipid levels.
Now let us look at what the World Stroke Organization (WSO) suggests doing differently to address those risk factors.
A paradigm shift:
Abandoning graded risk categorization and adoption of a risk continuum scale
The first is that their appeal for a paradigm shift of risk classification; they recommend abandoning mild, moderate, and high-risk categorization for heart and stroke problems; instead re-framing stroke risk along a continuum.
Population-wide prevention strategies
They underscore the need of adopting a population-wide approach to reduce the negative impact of behavioral (lifestyle) risk factors. Quite correctly, they also emphasize the need for integrating into the WHO HEARTS initiative, and the establishments and programs at all levels, global, national, and local.
Individual level interventions
Of course, individual interventions – screening for risk behaviors – also necessary; more specifically, poor diet, physical inactivity, alcohol use, and smoking and biological risk factors – elevated blood pressure and abnormal lipid profiles.
The WSO has introduced a free stroke riskometer app to aid this intervention strategy.
Combining community interventions with medicines and behavioral interventions for people at risk of stroke
They highlight five lifestyle risk factors (smoking, physical activity, diet, alcohol consumption, weight) based on evidence.
The WSO suggests several evidence-based implementation strategies. These are as follows;
- Using community health workers serving in other community health programs: They bring forward a meta-analysis of 16 RCTs as supportive evidence.
- Combining medical (medications for blood pressure and lipid level screening, medication for the needy) interventions with lifestyle modifications
- Integrating stroke and dementia strategies with WHO HEARTS Initiative
- Imposing taxes on unhealthy food, tobacco, and smoking and dedicate the revenue to prevention, screening, and treatment interventions.
As soon as a stroke strikes within minutes brain cells – neurons and glial cells – begin to die; each second costs as many as 32,000 neuron cells, 230 million synapses, and 200 meters of axonal fibers. In terms of minutes, each passing minute costs 1.9 million neuron cells, 13.8 billion synapses, and 12 kilometers of axonal fibers (Saver J.L. 2005).
So, every second
As far back as in 1993, Dr Camilo R. Gomez coined this exhortation – “Time is Brain” – in an editorial to the Journal of Stroke and Cerebrovascular diseases in 1993 – a quarter of a century ago (Gomez, 1993).
However, during the past 25 years with the advent of new knowledge of cerebral collateral perfusion, Dr Gomez updated his own proposition using computational modelling in this year- 2018. He concludes that the effect of time on the ischaemic process is relative. What does this mean? It means that this time window should not be considered as universal to all. It varies depending on the individual’s brain collaterals; the collaterals vary from person to person. In other words, while acknowledging that the “Tims is Brain” is still a valid slogan, we still proceed to act on the F.A.S.T. even the golden hour is elapsed.
How long blood supply should be blocked to have
Within the first 3 – 8 days after a stroke, the affected area swells more than the volume of this area. Then, re-organisation and retraction remove the dead tissues resulting in a volume smaller than the pre-affected brain area within the next 2 weeks to 3 months time (Saver J.L. 2005).
Brain’s internal collateral systems: (Image source: Stroke Journal)
You must have read my post on Brain’s blood flow: Journeys to the brain- 4. It is not the only oxygen and food supply route to the brain; we have our brain’s alternate collateral supply system too – just in case. This brain’s collaterals are a very recent finding. However, we have been known about the primary source of these collaterals: the Circle of Willis.
Circle of Willis
The yellow-colored circle is the “Circle of Willis” (Figure 1). It is well connected to the red-colored main supply routes.
In addition to the Circle of Willis, we own a secondary mechanism too. In other words, our brain has an alternate mechanism to keep brain cells alive whenever its blood supply is interrupted. Figure s summarises that channel system. David Liebeskind published an article about this system in the Stroke journal in 2003. According to him, these collaterals divert blood into affected regions. I have cited the url link below for those who are interested in reading about this topic more.
These collaterals, as we can easily understand, should be vital to minimizing the damage that may cause by an ischemic stroke. The author says that the extent of these collateral systems determines the clinical outcome.
The collaterals keep the neurons and their supportive cells alive until a rescue operation from us arrives. Hence, the extent of collaterals at the “war zone” is vital according to Jung Simon et al. (2017).
Jung S, Wiest R, Gralla J, McKinley R, Mattle H, Liebeskind D. Relevance of the cerebral collateral circulation in ischaemic stroke: time is brain, but collaterals set the pace. Swiss Med Wkly. 2017;147:w14538. Published 2017 Dec 11. doi:10.4414/smw.2017.14538
The term, “stroke” refers to a sudden stoppage of blood flow to a part of the brain. It can happen either due to a block to a supply route (artery) or a blast (rupture) in a supply route.
The block to a supply route occurs due to a blood clot that lodges within a blood supplying vessel, an artery, or one of its smaller branches.
- In the medical field, “stroke” is called “cerebrovascular accident” (in short, CVA).
- A stroke due to blockage due to a blood clot is called “ischemic stroke”.
- A stroke due to a broken supply route is called “hemorrhagic stroke”.
From the two types, the “ischaemic strokes” are much commoner than the “hemorrhagic strokes”. In the US, as much as 80 percent strokes are ischemic strokes according to the US government website.
There are common places where ischemic stroke strikes. One place is the junction where the main supply route (common carotid artery) divides into two smaller branches: internal and external. (Read the blood flow: Journeys to the brain-4.). These clots usually travel higher up and block a smaller artery. The extent of the damage depends on the size of the clot and part of the brain it blocks. See Figure 1.
Sometimes, a clot can originate within the heart itself too.
In a hemorrhagic stroke, blood seeps through from an arterial branch either due to a leak
Transient Ischaemic attack (TIA): “mini-stroke”
This term is used as its name implies a very brief attack due to a temporary blockage of a blood vessel. The block is caused by a very small blood clot which will dislodge by itself. This is considered a warning. However, it is a medical emergency meaning that we need to call 911 immediately.
The “mini-stroke” typically resolve within 24 hours; however, it can become a full-blown stroke if not attended.