Bleeding Control

The escalating framework

Bleeding control is not a single technique. It is a sequence of escalating steps, and which of them you use depends on how severe the bleeding is and on how it responds to what you have already done. Direct pressure is almost always step one, and for most wounds it is also the last step, because the bleeding stops there.

The table below pairs the situation you find with the intervention it calls for.

Table 29.1The escalating framework

Three kinds of bleeding, and the one that kills quickly

The appearance of the blood tells you which vessel is open, and that predicts how fast the patient is losing volume and how hard it will be to stop.

Arterial bleeding is bright red — it is fully oxygenated — and it spurts in time with the pulse, because it is under the pressure the heart generates. It is the hardest to control and the fastest to kill. Venous bleeding is darker red and flows steadily rather than spurting, because venous pressure is low and constant; it can still be heavy from a large vein. Capillary bleeding oozes from the surface, is dark red, and usually stops on its own.

Volume gives the urgency its scale. An adult holds roughly 5 liters of blood. Sudden loss of about 1 liter in an adult is serious; in a child the figure is around 500 mL, and in an infant as little as 100–200 mL. The same puddle on the floor means something very different depending on who is lying next to it, and a volume that an adult tolerates can be most of a small child's circulating blood.

Why direct pressure works

Pressure applied over a wound compresses the tissue around it, which diverts blood flow away from the damaged vessels and slows what still passes through them. Pressure from the outside also reduces the force of the bleeding from inside the vessel, and that gives the body's own clotting mechanism the time it needs to plug the holes in the vessel wall. In most cases this alone controls the bleeding.

Three methods deliver that pressure, and they differ mainly in how much of it you have to supply with your own hands: a gloved hand alone, a dressing held in place with a gloved hand, or a pressure dressing secured with a bandage.

Step-by-step procedure

The procedure runs in five steps, from the moment your hand reaches the wound to the point at which you decide that pressure is not working.

1. Apply firm pressure. Use the palm of your hand for larger wounds and your fingers for smaller ones, and direct the pressure toward an underlying bone wherever one is available. If the bleeding is severe or spurting, place a gloved hand directly on the wound immediately rather than spending time hunting for a dressing.
2. Hold the pressure firmly. For massive bleeding, maintain that pressure all the way to the hospital. For bleeding that is not massive, it is reasonable to check the wound after 5 to 10 minutes to see whether it has stopped.
3. Do not over-layer the wound with absorbent dressings. Piling on gauze soaks up blood without stopping the bleeding, and the extra layers cushion your hand away from the wound, which weakens the pressure you are trying to apply.
4. Convert to a pressure dressing once the bleeding is controlled. Bandage the dressing firmly in place so that the pressure is maintained without your hands.
5. Never remove a dressing once it has been placed. Taking it off can disrupt the clots that are forming under it. If blood soaks through, treat that as your signal to escalate, either to wound packing with a hemostatic agent or, for a wound on an extremity, to a tourniquet.

Taken as a whole, direct pressure is four ideas in order: compress the wound, hold the compression, leave what you have applied undisturbed, and escalate if it fails.

Nosebleeds are the common exception where position does most of the work

Epistaxis is managed by sitting the patient upright and leaning forward, then pinching the soft fleshy part of the nostrils together. Leaning the patient back, which is the instinct and the folk remedy, sends blood down the throat, where it is swallowed, irritates the stomach, and produces vomiting in a patient who is already bleeding. Forward and pinched is the whole technique.

The tourniquet stopped being a last resort, and the change is the point of this section

For decades a tourniquet was taught as the thing you tried when everything else had failed, on the belief that it cost the patient the limb. Military experience over the last two decades changed that. A correctly applied tourniquet left in place for the duration of a prehospital transport rarely costs a limb, and hesitation costs lives. Current civilian practice, reflected in the American College of Surgeons' Stop the Bleed program, is that life-threatening bleeding from an extremity gets a tourniquet immediately — not after the ladder of lesser measures has been climbed and failed.

A commercial windlass tourniquet is the device to use. Improvised tourniquets — a belt, a cravat and a stick — are a fallback when nothing else exists, and they fail more often, usually because they are too narrow to occlude the artery and merely occlude the veins, which makes the bleeding worse rather than better.

Applying it: where, how tight, and the two things you write down

Placement: about 2 to 3 inches proximal to the wound — between the wound and the heart — and never over a joint, because there is no single bone there to compress the artery against. If the wound is an amputation, if there are multiple wounds, or if you cannot see where the bleeding is coming from in a mangled limb, place it high and tight on the limb instead.

Tightness: tighten the windlass until the bleeding stops and the distal pulse is gone. Both endpoints matter. A tourniquet tight enough to occlude the veins but not tight enough to occlude the artery is the failure mode that makes bleeding worse: arterial blood still enters the limb while venous return out of it is blocked.

It will hurt, often badly, and the pain is not a reason to loosen it. Tell the patient that in advance.

Write down the time of application, on the tourniquet itself and in your report, and hand it off verbally. Leave it visible — never cover a tourniquet with a blanket or a dressing, because the next person needs to see it without hunting for it. And do not loosen or remove it in the field once bleeding is controlled.

If one tourniquet does not control the bleeding, apply a second one just proximal to the first rather than tightening the first past its limit.

Wound packing, and the places you must not pack

Some wounds cannot take a tourniquet because there is no limb to put it around. The junctional areas — the groin, the armpit, the base of the neck — are where a limb meets the trunk, and bleeding there is controlled by packing the wound and holding pressure, or with a purpose-built junctional device.

To pack: push gauze, plain or hemostatic, directly into the wound, down to the source of the bleeding, filling the cavity tightly, and then hold firm direct pressure over the packed wound for at least 3 minutes. Packing that is laid on top of a wound is a dressing, not packing, and it will not work. The pressure held afterward is not optional; hemostatic gauze works by accelerating clotting at the point of contact, and it needs the contact and the time.

Do not pack the chest or the abdomen. There is no cavity floor to pack against, the gauze goes somewhere you cannot control, and neither site can be compressed. Neck wounds are also not packed in the usual sense, because the packing can compress the airway; an occlusive dressing and direct pressure that does not obstruct breathing is the approach there.

The bleeding you cannot see is the bleeding you cannot compress

Internal bleeding has no puddle to point at, and the patient can lose a large fraction of their blood volume into the abdomen, the chest, the pelvis, or the tissue around a femur without a drop reaching the outside. You recognize it from mechanism and from signs rather than from blood.

Look for bruising and discoloration over the trunk, an abdomen that is distended, rigid, or tender, hematemesis (vomited blood, which may look like coffee grounds), melena (black tarry stool), hemoptysis (coughed blood), pain, swelling or deformity over a long bone, and — the finding that ties them together — signs of shock with no external bleeding to explain them. A femur fracture alone can hold well over a liter; a pelvic fracture can hold far more.

There is no field intervention that stops internal bleeding. The treatment is oxygen if indicated, keeping the patient warm, handling them gently, and rapid transport to a facility that can operate. Recognizing it early and shortening the time to that facility is the whole of the EMT's contribution, and it is a large contribution.

Shock is recognized before the blood pressure falls, because by then it is late

Hemorrhagic shock progresses in a way that is worth knowing as a sequence rather than a list, because the sequence is what lets you catch it early.

In compensated shock, the body is successfully defending its blood pressure. The heart rate rises, the vessels in the skin and gut constrict to shunt blood to the brain and heart, and the patient looks pale, cool and clammy, feels anxious or restless, and is thirsty. Respirations rise. The pulse pressure — the gap between systolic and diastolic — narrows, because the diastolic rises with vasoconstriction while the systolic does not. And the blood pressure is still normal. This is the stage at which recognition changes the outcome.

In decompensated shock, the compensation has run out. The blood pressure falls, mental status deteriorates, peripheral pulses become weak or absent, and the skin may become mottled or cyanotic. Hypotension is a late sign of shock, not an early one, and waiting for it in a patient who is pale, tachycardic and anxious means waiting for the patient to get worse before acting.

Two populations distort the picture. Children compensate extremely well and then crash abruptly, so a normal blood pressure in an injured child is not reassurance. And a patient on a beta blocker may not be able to mount the tachycardia that is the earliest sign, so their heart rate stays deceptively normal while they bleed.