Post by Woody Williams on Oct 9, 2009 9:23:56 GMT -5
WHAT YOU MUST KNOW TO SURVIVE IN A TREESTAND
By Dr. Norman Wood, 2009
Most hunters are not aware of the term Suspension Trauma, let alone the fact that you can die quickly in a safety harness from this killer. Most hunters feel that as long as they are wearing a full body safety harness and fall out of their treestand they will be fine, and most of the time you are. But if you fall and are unable to recover to a standing position, you can die in as little as 5 to 30 minutes. NASA studies have shown their personnel becoming unconscious in as little as 4 minutes while suspended in a harness and death will shortly follow unconsciousness. You must always use your full body harness correctly or it could cost you dearly.
This past year there were several hunters found dead hanging in their safety systems, two in one week in Ohio. On October 27, 2008 a 48 year old man in Portage County was found deceased hanging about 25 feet from the ground and on November 2, 2008 a 35 year old man in Carroll County was found deceased hanging 20 feet from the ground. One of the victims had a cell phone with him. And that is the point; you may not even have time to use a cell phone if you are ever caught suspended from your treestand.
In the industrial workplace, the prompt response time for emergency personnel to reach a suspended worker is approximately six (6) minutes. If you are able to contact someone do you think they could be there in 6 minutes? If you currently own a full body safety harness, take a good look at the warning labels. You will probably find one that says "PROLONGED HARNESS SUSPENSION CAN BE FATAL". And the manufactures are serious; everyone needs to be aware of suspension trauma and how it can harm you.
Let me be absolutely clear, everyone should ALWAYS wear a full body safety harness whenever in a treestand; it can save your life. You should be connected to the tree from the time you leave the ground until the time you get back down. There are plenty of different harnesses, the Rescue One CDS (Controlled Descent System), Non-CDS harnesses with suspension relief straps, Ascend/Descend Safety Lines and Lineman's Ropes available on the market today to keep you safe, and you should always be using them correctly as instructed.
So let's see how suspension trauma can be fatal. You first need to know a little about how your blood circulation works. The heart is nothing more than a living mechanical pump; to force blood out it must have a steady supply of blood coming in. The less blood returning to the heart the lower the blood pressure drops. Blood returns to the heart by the veins from the entire body. The blood then goes through the 1st half of the heart to the lungs to pick up oxygen and then back to the 2nd half of the heart where it is pumped back out to the body through the arteries.
As the blood leaves the heart it has significant pressure from the pumping action. But when the blood starts to return to the heart, the pressure is very low, it just seeps. This is because the blood has gone from the large arteries down to the microscopic capillaries and back to the veins. It is like putting a garden hose up against a large sponge. The water just seeps through and has very little pressure behind it.
When you are wearing a full body harness, like you always should, and if you fall from your treestand you will first be thankful that you're not lying on the ground either dead or busted up. But you only have a few minutes to get back to your feet. You can start feeling the effects of suspension trauma very quickly, and this is why. Your body's weight is pushing down on your leg straps so hard that it is causing a tourniquet affect on the large veins in your legs. This pressure stops the blood in the legs from returning back up to your heart.
The powerful heart can pump the arterial blood down into your legs, but the low pressure venous blood can't get back up. And this is the bad news; this is called Blood Pooling and the legs can store up to half of your total blood volume. It is just like having a major blood loss of about half of your blood without it ever leaving the body. It is the same thing as cutting both of your wrists and loosing half of your blood, and you know how long you would live that way. The longer you hang in your harness the less and less blood there is to circulate through the heart and lungs to keep you alive. Meaning your blood pressure starts to drop the moment you start being suspended because the heart has less and less blood to pump. Now the heart sensing this loss in volume increases its rate and pumps harder to try to keep the pressure up. It is killing you at an increasingly faster rate. The faster and harder your heart pumps, the more blood that goes into your legs where it pools, unable to return to the circulation.
You are now in a rapid downward spiral to death. But the body has a safety mechanism if this happens. It is called fainting. If the body has a significant drop in blood pressure you pass out because of the lack of oxygen to the brain. You fall to the ground and lay in a horizontal position and the blood returns to your heart and brain and you wake up. The bad news for you is that your harness is keeping you in the worse possible position if this happens; it keeps you in a vertical position. If you cannot get back to a standing position either back on your stand, on the ground or on a suspension relief strap to get the pressure off of your legs so the blood starts circulating again, you will become a suspension trauma victim pretty quick. It is only a matter of time and you will never know how much time you have.
So while you're hanging in your harness, your blood pressure is dropping by the second. There is less and less circulating blood to your heart and brain so there is less oxygen to keep you alive. You will begin to feel really bad and your heart will be pounding out of your chest as it pumps harder and harder trying to keep the pressure up. In just a couple of minutes the pain from the leg straps cutting into your groin will be unbearable. Your lower legs will go numb and your breathing will become rapid and more and more difficult as you struggle to stay alive.
You will be exhausted and dying, and without the right equipment on you, there is nothing you can do to stop it. As the blood pressure and oxygen reach a critical low level you pass out thinking of your loved ones. After becoming unconscious the heart will continue to pump as hard as it can in a futile attempt to live. As the blood pressure and oxygen level continues to drop, your brain experiences oxygen starvation and is forever damaged.
Your heart then experiences oxygen starvation and since it cannot adequately pump any longer, slows and finally stops altogether when it experiences a massive global myocardial infarction or heart attack when it runs out of oxygen.
In just a very few minutes, you have gone from having a great time being back in the woods doing what you love, to being killed while hanging in your safety harness. Your family, friends or the emergency personnel will find your lifeless body and lower it to the ground. The loss to your family will be insurmountable, a horrific tragedy that could have been prevented. And this exact scenario happens every year, several times.
There is one more vital piece of information that you must know and this has to do with the blood that has pooled in your legs. While hanging in your harness, the large amount of blood that has been pumped into your legs has changed considerably. In a couple of minutes all of the oxygen has been used up by the leg muscles and when that is gone, the muscle cells start what is called anaerobic metabolism or no oxygen metabolism to stay alive.
During anaerobic metabolism the muscles cells dump a large amount of acidic by-products that are toxic in large amounts back into the blood. At this same time since the blood is no longer moving micro blood clots can start forming in as little as 6 seconds. So what was once life sustaining blood has become a toxic sludge with clots and no oxygen.
And this is what you must remember. If you have been suspended in a harness for more than just a couple of minutes and if by some way you are able to perform a self rescue or if someone rescues you DO NOT LIE DOWN. If you do, all of that toxic sludge which was once blood will go racing back to your heart and you may die right there from a fatal cardiac arrest or a few days later from acute kidney or liver failure.
You need to stay upright for at least 30 to 40 minutes to allow the slow introduction of the pooled blood back into the circulation. If you must, sit down with your back up against a tree to keep your upper body elevated. Get back on your feet as soon as you can."
By Dr. Norman Wood, 2009
Most hunters are not aware of the term Suspension Trauma, let alone the fact that you can die quickly in a safety harness from this killer. Most hunters feel that as long as they are wearing a full body safety harness and fall out of their treestand they will be fine, and most of the time you are. But if you fall and are unable to recover to a standing position, you can die in as little as 5 to 30 minutes. NASA studies have shown their personnel becoming unconscious in as little as 4 minutes while suspended in a harness and death will shortly follow unconsciousness. You must always use your full body harness correctly or it could cost you dearly.
This past year there were several hunters found dead hanging in their safety systems, two in one week in Ohio. On October 27, 2008 a 48 year old man in Portage County was found deceased hanging about 25 feet from the ground and on November 2, 2008 a 35 year old man in Carroll County was found deceased hanging 20 feet from the ground. One of the victims had a cell phone with him. And that is the point; you may not even have time to use a cell phone if you are ever caught suspended from your treestand.
In the industrial workplace, the prompt response time for emergency personnel to reach a suspended worker is approximately six (6) minutes. If you are able to contact someone do you think they could be there in 6 minutes? If you currently own a full body safety harness, take a good look at the warning labels. You will probably find one that says "PROLONGED HARNESS SUSPENSION CAN BE FATAL". And the manufactures are serious; everyone needs to be aware of suspension trauma and how it can harm you.
Let me be absolutely clear, everyone should ALWAYS wear a full body safety harness whenever in a treestand; it can save your life. You should be connected to the tree from the time you leave the ground until the time you get back down. There are plenty of different harnesses, the Rescue One CDS (Controlled Descent System), Non-CDS harnesses with suspension relief straps, Ascend/Descend Safety Lines and Lineman's Ropes available on the market today to keep you safe, and you should always be using them correctly as instructed.
So let's see how suspension trauma can be fatal. You first need to know a little about how your blood circulation works. The heart is nothing more than a living mechanical pump; to force blood out it must have a steady supply of blood coming in. The less blood returning to the heart the lower the blood pressure drops. Blood returns to the heart by the veins from the entire body. The blood then goes through the 1st half of the heart to the lungs to pick up oxygen and then back to the 2nd half of the heart where it is pumped back out to the body through the arteries.
As the blood leaves the heart it has significant pressure from the pumping action. But when the blood starts to return to the heart, the pressure is very low, it just seeps. This is because the blood has gone from the large arteries down to the microscopic capillaries and back to the veins. It is like putting a garden hose up against a large sponge. The water just seeps through and has very little pressure behind it.
When you are wearing a full body harness, like you always should, and if you fall from your treestand you will first be thankful that you're not lying on the ground either dead or busted up. But you only have a few minutes to get back to your feet. You can start feeling the effects of suspension trauma very quickly, and this is why. Your body's weight is pushing down on your leg straps so hard that it is causing a tourniquet affect on the large veins in your legs. This pressure stops the blood in the legs from returning back up to your heart.
The powerful heart can pump the arterial blood down into your legs, but the low pressure venous blood can't get back up. And this is the bad news; this is called Blood Pooling and the legs can store up to half of your total blood volume. It is just like having a major blood loss of about half of your blood without it ever leaving the body. It is the same thing as cutting both of your wrists and loosing half of your blood, and you know how long you would live that way. The longer you hang in your harness the less and less blood there is to circulate through the heart and lungs to keep you alive. Meaning your blood pressure starts to drop the moment you start being suspended because the heart has less and less blood to pump. Now the heart sensing this loss in volume increases its rate and pumps harder to try to keep the pressure up. It is killing you at an increasingly faster rate. The faster and harder your heart pumps, the more blood that goes into your legs where it pools, unable to return to the circulation.
You are now in a rapid downward spiral to death. But the body has a safety mechanism if this happens. It is called fainting. If the body has a significant drop in blood pressure you pass out because of the lack of oxygen to the brain. You fall to the ground and lay in a horizontal position and the blood returns to your heart and brain and you wake up. The bad news for you is that your harness is keeping you in the worse possible position if this happens; it keeps you in a vertical position. If you cannot get back to a standing position either back on your stand, on the ground or on a suspension relief strap to get the pressure off of your legs so the blood starts circulating again, you will become a suspension trauma victim pretty quick. It is only a matter of time and you will never know how much time you have.
So while you're hanging in your harness, your blood pressure is dropping by the second. There is less and less circulating blood to your heart and brain so there is less oxygen to keep you alive. You will begin to feel really bad and your heart will be pounding out of your chest as it pumps harder and harder trying to keep the pressure up. In just a couple of minutes the pain from the leg straps cutting into your groin will be unbearable. Your lower legs will go numb and your breathing will become rapid and more and more difficult as you struggle to stay alive.
You will be exhausted and dying, and without the right equipment on you, there is nothing you can do to stop it. As the blood pressure and oxygen reach a critical low level you pass out thinking of your loved ones. After becoming unconscious the heart will continue to pump as hard as it can in a futile attempt to live. As the blood pressure and oxygen level continues to drop, your brain experiences oxygen starvation and is forever damaged.
Your heart then experiences oxygen starvation and since it cannot adequately pump any longer, slows and finally stops altogether when it experiences a massive global myocardial infarction or heart attack when it runs out of oxygen.
In just a very few minutes, you have gone from having a great time being back in the woods doing what you love, to being killed while hanging in your safety harness. Your family, friends or the emergency personnel will find your lifeless body and lower it to the ground. The loss to your family will be insurmountable, a horrific tragedy that could have been prevented. And this exact scenario happens every year, several times.
There is one more vital piece of information that you must know and this has to do with the blood that has pooled in your legs. While hanging in your harness, the large amount of blood that has been pumped into your legs has changed considerably. In a couple of minutes all of the oxygen has been used up by the leg muscles and when that is gone, the muscle cells start what is called anaerobic metabolism or no oxygen metabolism to stay alive.
During anaerobic metabolism the muscles cells dump a large amount of acidic by-products that are toxic in large amounts back into the blood. At this same time since the blood is no longer moving micro blood clots can start forming in as little as 6 seconds. So what was once life sustaining blood has become a toxic sludge with clots and no oxygen.
And this is what you must remember. If you have been suspended in a harness for more than just a couple of minutes and if by some way you are able to perform a self rescue or if someone rescues you DO NOT LIE DOWN. If you do, all of that toxic sludge which was once blood will go racing back to your heart and you may die right there from a fatal cardiac arrest or a few days later from acute kidney or liver failure.
You need to stay upright for at least 30 to 40 minutes to allow the slow introduction of the pooled blood back into the circulation. If you must, sit down with your back up against a tree to keep your upper body elevated. Get back on your feet as soon as you can."
