Haemostatic Agents - Real First Aid

A brief guide to Haemostatic Agents

Haemostatics are applications designed to stem blood-flow through the accelerated promotion of clotting. As with all treatments it is important to understand their roles, applications and the differences between them.

Considerations

Haemostats are not the first line treatment for serious bleeds. Always start with direct pressure and elevation before considering haemostatics.
They are used with direct pressure and dressings – not instead of.
Every haemostatic agent (brand and type) is different and familiarisation training should be sought.
They are used appropriately on moderate to severe haemorrhage (at the source of the bleed)
The packaging should be retained and handed-over to the EMS with the instruction that it goes with them to hospital to enable their wound to be managed effectively. Do not assume the hospital will know how to deal with the haemostat you have applied.

Application

The primary treatment for all serious bleeds is direct pressure and elevation. All haemostats are designed to be used with direct pressure at the site of the bleed – directly onto the bleeding artery, deep within the wound if necessary. They are not a ‘magic powder’ that can be casually applied and left to work.

Most brands are available as either a loose, granular powder or either impregnated onto a bandage or retained inside a porous bag. Loose powders present issue when trying to apply them accurately over, or into, the wound site and can be blown around by the wind. Haemostats should never be allowed to enter:

The eyes
The airway
The abdominal or thoracic cavities.

Powdered products cannot be applied against gravity – for example packing a wound underneath a casualty – nor can they be applied against very fast flowing blood.

As such, haemostatic bandages, gauzes and ‘sponges’ are often easier and more practical to apply. These dressings are also easier to remove and clean in theatre, once the casualty gets to hospital.

QuikClot^tm Z-Medica

One of the first haemostats to market, Z-Medica’s QuikClot (QC) products have been a longstanding choice of both the US and UK military. While effective, the early version suffered from one major drawback; it generated significant heat causing both pain, cell damage and in some cases partial thickness burns:

http://emj.bmj.com/content/27/12/950.extract

QC is currently available as their 2^nd generation products containing Zeolite as well as the more recent 3^rd generation products’ whose primary ingredient is Kaolin

2^nd generation Zeolite products work in a variety of ways which initiate the natural process of clotting:

Adsorption of water thereby accelerating fibrin formation platelet activation
Activation of the coagulation cascade due to the “glass effect”
Supplying a resource for Ca++, a cofactor in the coagulation cascade
A large zeolite pore surface area facilitating fibrin formation

While an improvement on the 1^st Generation products which generated heat of up to 72^oc, the 2^nd generation products have been seen to generate heat up to 42^oc.

2^nd generation Zeolie products include:

QuikClot granular
QuikClot 1st Response
QuikClot ACS+
QuikClot Sport
QuikClot Sport Silver

With the exception of the granular form, the other products are dispensed in a ‘tea bag’ like sachet which is applied directly to the wound. This removes the problems associated with handling loose granules and enables a large area to be covered, deep wounds to be filled and direct pressure to be effectively applied. This method of application also facilitates the quick and easy removal of the product in theatre. Conversely, this method is not ideal for treating small, deep puncture wounds or incisions.

3^rd generation QC products use Kaolin, a white aluminosilicate which effectively jump-starts the chemical process of clotting without discernable heat generation.

Kaolin based products include:

Quickclot 2x2
Quickclot 4x4
Quickclot Combat Gauze

In these products blood is not absorbed by the product, rather it reacts with it.

Celox^tm Celox Medical

Celox is made from chitosan, a naturally occurring, bio-compatible polysaccharide. Because chitosan has a positive charge, it attracts red blood cells, which have a negative charge. Unlike Quickclot, the active element of Celox absorbs water from the blood, leaving behind a greater concentration of clotting factors promoting clotting and forming a gel-like clot or ‘plug’ with an inherent coherent seal.

These products are relatively benign, as they are neither procoagulants nor do they generate heat in use. Chitosan is extracted from shrimp shells, so there have been inevitable questions about whether it could trigger shellfish allergies. An allergy study was performed on 212 human subjects who were allergic to shellfish and no positive allergic reactions were noted. The study summary is available upon request from Celox Medical. There are no cases on record of allergic reaction to Celox, and it is considered hypo-allergenic.

The gel-like clot is also considered more stable than the clots formed with Quickclot and less likely to be disturbed with repeat bleeding. Celox is also easier to clean in theatre, usually with normal saline. Chitosan is naturally broken down by the body’s natural enzymes unlike Kaolin or minerals used in other haemostats which will remain in the body indefinitely unless removed.

Celox Gauze – 3” x 5’ - £33.49 + VAT

HemCon^tm www.hemcon.com

HemCon Medical Technologies’ HemCon products are also chitosan-based haemostatic and works on the same ion exchange principle as Celox. Hemcon is a mucoadhesive pad which as well as promoting clotting is intended to seal the wound (like a puncture repair) but, being fairly rigid, is not efficient as efficient at dealing with deeper wounds. The 4” x 4” has an rrp of £99.95 + VAT.

A more recent product from Hemcon is the rolled gauze-like Chitoflex bandage 7.5cm x 71cm which can be packed deep into wounds. Rrp £160.95 + VAT Yes, you read that correctly.

Recommendations

Depending on who you read – and when – different products will be claimed to be issued to (or withdrawn from) pre-hospital, military or law enforcement agencies. Do not take these statements as testament to their efficacy or appropriateness for use because:

Most decisions regarding approved equipment are chosen by senior management and largely on the basis of cost, not efficacy or appropriateness.
The working remit of these professionals affords them the support of their employers when exercising the use of one of these products. An individual using any of these without the approval of the agency they are operating under at the time, is not afforded that protection should things go wrong.

There are a number of independent studies which have examined the efficacy of these products, for example:

http://citerahiadesgenettes.hautetfort.com/media/00/01/3315550226.pdf

The Case For:

Haemostatics were designed for use in combat situations, where catastrophic haemorrhage accounts for 50% of trauma relate casualties. Haemostatics were not designed to replace the use of direct pressure, nor were they designed to do the job any better, just quicker. This enables the rescuer to deal with multiple casualties and to look after after themselves in a hazardous environment before evacuating to definitive care as quickly as possible.

Military medicine has explored possibilities that are rarely applied to conventional, urban First Aid situations but similarities can be drawn to remote or hazardous industrial settings.

They are best used in a similar context; high risk and / or multiple casualties. Haemostatics might be appropriate to civilian rescue teams, especially in a high-risk industrial setting.

The Case Against:

Haemostatics should not be left in place for more than 24 hours. If the casualty cannot be evacuated to definitive care within this time, their use is not appropriate. This might limit their use in extremely remote environments.

A casualty with a catastrophic haemorrhage is very poorly. Evidence suggest that this may account for 50% of trauma related fatalities, more to the point, these fatalities typically occur within one hour of the causing incident. Whilst the haemostatic should not be left for more than 24 hours, can you evacuate your casualty to definitive care within one hour?

Haemostatics enable the rescuer to deal with multiple casualties. If there is only one casualty is their use justified? If you have not had formal training or are not operating under guidance, can you justify your actions?

All of the products mentioned here are commercially available. Whilst they have their purpose as well as their pros and cons, it is the responsibility of the user to understand the product (beyond the scope of this article) and receive training in the products before they are used.

Related article: Duty of Care and The Law