Harness Hang Syndrome or Venous Pooling

The Harness Hang Syndrome, HHS, is caused by the physical effects of Venous Pooling.   The term “Harness Hang” causes many riggers to believe the effect is caused by constriction of the veins by rope or other supports around the legs during a suspension.  While these restrictions may aggravate the problem, they are not a necessary condition to cause the problem.

Here are google searches for Harness Hang Syndrome, and Venous Pooling.

In December 2005, I experienced the problem during one of my suspensions.   I then studied the literature for the causes and treatments of the problem. In February 2006, I published a paper, Harness Hang Syndrome in Suspension Bondage, with the results of my study and my conclusions.   I posted my paper, on several yahoo groups, including my Houston-BondageSIG, the local bondage groups for Dallas and Austin, and Jimi Tatu’s very large international Adult Rope Art yahoo group.  [EDIT: Here is my original paper – Harness Hang Syndrome in Suspension Bondage ]

There was a vigorous discussion of my paper and conclusions on these groups, particularly the Adult Rope Art group.  I am the Gary in this post on Jimi Tatu’s website.

If you are not a member of these groups, click here to download my paper, Harness Hang Syndrome in Suspension Bondage.

(When I first started my journey into this wonderful world of shibari, my screen name was “ClintEman”.  For years, some of both my vanilla and kinky friends have called me Dr. Z.   So, a couple of years ago, I changed my screen name from “ClintEman” to “DoctorZ”.)

My conclusions, based on my study of the literature, are:


What are the causes of Harness Hang Syndrome (HHS)?

It appears to me, only two requirements exist for HHS to occur:

1) a body position that allows blood to accumulate from gravity (venous pooling) in the legs or arms, and

2) lack of motion – so that the “muscle pumps” don’t redistribute the blood back into the body cavity in a near normal fashion.

Is constriction of arteries or veins necessary to cause the Harness Hang Syndrome?

Constriction of arteries or veins may aggravate the problems – but it is not necessary to cause the Harness Hang Syndrome.

Do you lay a victim suffering from the Harness Hang Syndrome down after releasing them from the suspension?

No. This is counter-intuitive. Many people tend to think it is important to lay the victim down to get blood into the brain. However, it is important to sit the victim upright for a while. When the blood that has accumulated in the legs flows abruptly into the heart it creates a risk of heart failure due to overstrain.

How do you avoid the Harness Hang Syndrome in a bondage suspension?

The cause of the Harness Hang Syndrome is lack of motion; not using the “muscle
pumps” in the arms/legs to help redistribute the blood that accumulates in arms/legs hanging lower than the body cavity. It seems logical if you eliminate these conditions, you should eliminate the risk of Harness Hang Syndrome.

1) Don’t allow your bottom to be motionless. If their legs are suspended below their body, be sure they move their legs. Make them flex their muscles. By moving or flexing their legs, they activate the “muscle pumps” in their legs and you should not have the HHS problem.

2) It seems logical that another way to avoid the problem is to make sure your bottom’s legs and arms are at least horizontal with or slightly above the body cavity. This position prevents the blood from accumulating in the legs or arms due to gravity, which removes one condition/requirement for causing the HHS.


Please read the footnotes in my paper.  They are excerpts from peer reviewed published papers.  They tell the story.

 I  have also witnessed the venous pooling problem in a non-suspension BDSM play scene.

The setup for venous pooling (or the Harness Hang Syndrome) is actually very simple – motionless with legs below the body cavity.  This allows the blood to drain from the body cavity into the veins in the legs without the help of the muscle pumps in the legs to return the blood back into the body cavity.  And, it doesn’t have to be a suspension.  Just standing motionless will have the same effect.

I witnessed this incident at a BDSM party.  A BBW bottom stood in one of those vertical cages fabricated with leather straps in a basket type weave.  They are designed for the bottom to stand encapsulated and motionless and gently swing from an overhead hard point.  I’ve seen scenes with this vertical cage toy done several times, and the experience for the bottom seems wonderful.

In the incident I am relating, when this BBW bottom was released she had all the symptoms of HHS.  The setup for HHS was simple – “motionless with her legs below her body cavity”.

I also think there is more of a risk when the bottom (male or female) is not in good physical shape.  I think the lack of muscle tone in their legs makes it easier for their veins to expand, creating a larger reservoir for the blood from the body cavity to drain into, effecting a more serious reduction of blood supply for the heart to work with.

I personally have had two incidents with venous pooling or HHS in my suspensions.  Both times my bottoms were BBW, and not in physically good shape.  Once I learned how to avoid the setup for HHS – motionless with legs below the body cavity,  I no longer have a problem with venous pooling or HHS.

In my limited experience, I’ve seen the venous pooling or HHS victims recovery very quickly — in a few minutes.  They have been nauseous as a result of the experience.  Once they begin to recover and they no longer feel nauseous, they tend to want to just sit around, until they are feeling better.  In my limited personal experience, it doesn’t take long for them to begin to feel better.  But, they don’t seem to be ready for much more play right away.

I hope this post helps others avoid the problem.  Play safe and have fun.

2 thoughts on “Harness Hang Syndrome or Venous Pooling

  1. I just love the internet.

    I placed this post on my blog about 3 hours ago. Within the last hour, I received an email from an MD reporting to me on updated medical advice. Here is the important information in that email —


    “Your recent note about harness suspension came up on a google search. … What you have written about not laying someone down after this happens was current several years ago but most medical authorities no longer support that point of view. Below is a link to a review article …


    That part of the review by Seddon that you cite has been more or less retracted by the occupational safety group that wrote it.


    Based on that, OSHA has removed the bulletin that you cite as well (no link as it’s no longer available from OSHA). If you use google scholar you’ll find several publications saying that there was never any evidence for that recommendation (e.g. Thomassen, Adisesh, Pasquier). There was a comment on your site recommending an article by Raynovich. This article stands in isolation from all other medical sources. It was briefly cited by the Mountain Rescue Association but they have subsequently said to do standard resuscitation for suspension trauma.


    … What you wrote was mainstream “common knowledge” in 2006 but it is no longer felt to be accurate and is felt to be probably dangerous by many. Many people may read your posts and it may make a difference.”


    I’ve only looked at these articles briefly, and won’t really have time to read them thoroughly for a few days. But, I wanted to post this information as soon as possible.

    The previous literature I’ve read suggests it is necessary to sit a venous pooling victim up during the initial recovery period, rather than laying them down. Sitting a venous pooling patient up during the initial rescue period is counter-intuitive to emergency rescue personnel. As I read this new literature, it suggests it is best to use standard rescue procedures and lay the venous pooling victim down as soon as possible during/after rescue.

    I wanted you to know these medical recommendations as soon as possible. I’m just reporting the literature.

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