Introduction to the Concept of Trauma and Hemostasis
Trauma refers to external injuries to the body caused by external forces such as impacts, collisions, and chemical erosions.
Blood, a vital substance for sustaining life, circulates through the heart and vascular chambers. An adult's blood volume accounts for about 8% of their body weight, and bleeding is one of the major complications following trauma.
Bleeding occurs when blood vessels rupture, causing blood to escape into areas outside the vessels. It is both the most common and most likely occurrence following trauma. Severe trauma often results in significant blood loss, endangering the victim's life. Effective and timely hemostasis (blood stopping) is crucial for saving lives at the scene of an injury.
Classification of Trauma
Based on the cause of injury: Trauma can be categorized into mechanical injuries, such as cuts, crush injuries, lacerations, and falls; animal bites; and chemical injuries, such as burns and scalds.
Based on the severity of the injury: Trauma can be classified into mild, moderate, and severe levels.
Based on the nature of the wound: There are open wounds, like stab wounds, which expose the injury to the environment, increasing infection risks, and closed wounds, which, though they may show no visible signs, can lead to more severe internal damage.
Assessment of Traumatic Bleeding Sites
Subcutaneous bleeding: Typically results from falls, impacts, or bruises, leading to hematomas or bruises that often heal independently.
Internal bleeding: Not visible externally, this type of bleeding occurs when blood vessels rupture, allowing blood to flow into body cavities such as the thoracic, abdominal, or cranial cavities. Diagnosis relies on symptoms like pallor, vomiting blood, abdominal pain, or a weak pulse. Severe cases necessitate emergency medical intervention.
Evaluation techniques for internal bleeding include:Examining for bleeding indicators such as in the mouth, sputum, feces, or urine.Observing systemic symptoms including pallor, cold sweats, and weak pulse, and assessing for swelling or pain in critical areas like the chest, abdomen, or skull to determine the extent and specific site of bleeding.
External bleeding: Easily identifiable as blood flows out from the injury site. Management involves direct measures to control the bleeding and prevent further complications.
Identification of Different Types of Vascular Bleeding
Arterial Bleeding: Characterized by high oxygen content, arterial blood is bright red and spurts out in a forceful stream. Significant blood loss can occur rapidly and, if not immediately controlled, may be life-threatening.
Venous Bleeding: Venous blood, which has a lower oxygen content, flows continuously and is darker red in color. Delay in managing this type of bleeding can lead to prolonged, substantial blood loss, and potentially endanger life.
Capillary Bleeding: This type of bleeding manifests as a trickle of blood that shifts from bright to dark red. The amount of blood lost is generally minimal, and it often ceases spontaneously.
Common Hemostasis Methods for Traumatic Bleeding
1.Compression Hemostasis
(1)Direct Compression on the Wound
Direct compression is suitable for minor bleeding. Clean gauze, sterile gauze, clean towels, clothing, or scarves can be used to apply pressure to the bleeding site, achieving the purpose of stopping the bleed. Generally, pressing for about 10 minutes is sufficient to halt the bleeding.
Detailed Steps:
① Apply Pressure: Place a clean cloth or towel over the wound and apply direct pressure for 10-20 minutes.
② After Stopping the Bleed: Gently wrap the wound with a bandage, being careful not to bind it too tightly.
③ Avoid Certain Materials: Do not use degreased cotton or paper pads on the wound, nor apply any medications directly to it.
④ Cleaning the Wound: If the wound is not contaminated with dirt, rinse it with a liquid first; avoid using soap.
⑤Handling Clots and Debris: Do not wipe away blood clots or plasma around the bleeding wound, nor remove debris like glass shards from within the wound. Seek immediate medical attention at a hospital.
(2) Digital Pressure Hemostasis
Digital pressure hemostasis is appropriate for severe bleeding in specific areas like the head and limbs. The technique involves using fingers to press an artery near the heart against an underlying bone to obstruct blood flow and achieve hemostasis.
Important Considerations:
Use the index or ring finger to locate the pressure point, not the thumb, as the thumb's central artery is larger and may lead to misjudgment.Once the arterial pressure point is identified, apply pressure with the thumb or multiple fingers.
① Head and Facial Artery Compression Techniques
Temporal Artery Compression:
- Applicable for severe bleeding on one side of the head and forehead.
- Use the thumb of one hand to press the temporal artery below the injured side's temporomandibular joint, compressing the superficial temporal artery.
- Use the other hand to stabilize the victim's head.
Facial Artery Compression:
- Suitable for severe facial bleeding injuries.
- Use the thumb and index finger or the thumb and middle finger of one hand to press a depression about 1 cm below the anterior lower margin of both sides of the face, obstructing the flow of facial arteries.
- Due to the interconnected branches of the facial arteries, both sides require compression.
Postauricular Artery Compression:
- Applicable for severe bleeding caused by injuries behind one ear.
- Use the thumb of one hand to press the depression below the mastoid process on the injured side, obstructing the flow of the postauricular artery.
- Use the other hand to stabilize the victim's head.
Occipital Artery Compression:
- Suitable for severe bleeding near the occipital bone on one side of the head.
- Use the four fingers of one hand to press the depression between the area behind the ear and the prominence of the occipital bone, obstructing the flow of the occipital artery.
- Use the other hand to stabilize the victim's head.
②Limb Artery Compression Methods for Hemostasis
Finger Bleeding:For severe bleeding from a finger, use the thumb and index finger to pinch the digital arteries on both sides at the base of the injured finger.
Brachial Artery Compression: Suitable for severe bleeding below the elbow. Use the thumb of one hand to press against the inner mid-section of the upper arm to compress the brachial artery, while the other hand stabilizes the injured arm.
Radial and Ulnar Artery Compression: Applicable for severe bleeding in the hand. Use the thumbs and index fingers of both hands to compress the radial and ulnar arteries on either side of the injured wrist to stop the blood flow. Due to the extensive anastomotic branches in the palm, compression on both sides is necessary.
Digital (Toe) Artery Compression: For severe toe bleeding, use the thumb and index finger to compress the digital arteries on both sides of the injured toe.
Femoral Artery Compression:Suitable for severe bleeding in one lower limb. Use both hands, thumbs, fists, or the heel of the hand to press down slightly below the midpoint of the inguinal groove on the injured leg. The compression should be sustained for a longer period, and the injured person should be in a sitting or lying position.
Anterior and Posterior Tibial Artery Compression: For severe foot bleeding, use the thumbs and index fingers of both hands to compress the anterior tibial artery on the dorsum of the foot and the posterior tibial artery between the heel and the inner ankle.
Popliteal Artery Compression Point:Used for severe bleeding in the lower leg and below. After feeling the pulse of the popliteal artery in the middle of the popliteal fossa, use the thumb or the heel of the hand to deeply press it into the fossa to stop the bleeding.
Subclavian Artery Compression Point: Use the index finger to press the pulsation point of the subclavian artery in the middle of the clavicle pit and press toward the first rib.
2.Packing Hemostasis Method
For bleeding caused by deep soft tissue vascular injuries, such as epistaxis, deep neck wounds, or deep wounds in the thighs or back, it is often difficult to locate the bleeding site, and both arterial and venous injuries may be present simultaneously. After quickly cleaning and disinfecting the area, use sterile gauze to pack the wound tightly, followed by applying a large piece of sterile dressing to compress and bandage the wound for hemostasis.
3.Flexion Hemostasis Method
When compression hemostasis is ineffective for limb bleeding and there is no fracture, extreme flexion of the joint can be used to compress the vessels and achieve hemostasis. For example, if there is bleeding in the forearm or lower leg, place a cotton pad at the elbow or knee, then bend the joint to its extreme. Finally, use a figure-eight bandage to temporarily bind the lower leg to the thigh or the forearm to the upper arm to stop the bleeding.
4.Pressure Bandaging Hemostasis Method
The pressure bandaging method is widely used for various wounds. The materials used for bandaging are pads made of gauze and bandages. First, cover the wound with a sterile dressing, then place a clean folded gauze or bandage, sized to the wound, on top of the sterile dressing. Finally, apply pressure with the bandage and wrap it tightly to stop the bleeding, ensuring that the distal artery still pulses.
If the bandage is too loose, it will not effectively stop the bleeding. If it is too tight, it can cause ischemia and necrosis in the distal tissues. This method should not be used if there are bone fragments in the wound to avoid aggravating the injury.
5.Tourniquet Hemostasis Method
This method is used to control bleeding from large, complex, or fast-bleeding wounds in the limbs, often caused by the rupture of major blood vessels or the failure of other emergency measures. A tourniquet typically consists of an elastic band or any item at hand, such as a belt, tie, scarf, towel, headband, cloth, or triangular bandage.
The tourniquet should be tied proximal to the wound, on the side of the limb closest to the heart. For example, for bleeding below the knee joint, the tourniquet should be tied at an appropriate position on the thigh. If there is continuous bleeding below the elbow joint, the tourniquet should be tied above the elbow. When applying a tourniquet, it should be tightened until there is little or no fresh blood flowing from the wound.