Activity Three: Where s the Bleeding?

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Dinah Leonard
5 years ago
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Activity Three: Where s the Bleeding? There are five main sites of potentially fatal bleeding in trauma, remembered by the phrase on the floor and four more.

Even bleeding from a major artery can usually be controlled by a combination of tourniquets and direct pressure on the wound.

1 Activity Three: Where s the Bleeding? There are five main sites of potentially fatal bleeding in trauma, remembered by the phrase on the floor and four more. On the floor refers to losing blood externally this is easy to see and dramatic but the easiest to fix. Even bleeding from a major artery can usually be controlled by a combination of tourniquets and direct pressure on the wound. The other four compartments are internal bleeding, which is more difficult to manage: 1. Chest: Each lung sits inside a protective sac called the pleura. Each pleural cavity can contain approximately five litres of blood. Bleeding can come from laceration of blood vessels in the chest or from laceration of the lung tissue itself (lung tissue contains lots of blood vessels). Initial treatment consists of inserting a chest drain (a plastic tube) into the pleural cavity to evacuate the blood (this allows the lung to re-inflate and blood loss to be properly quantified). Depending on the injury the bleeding may stop without further intervention or require surgery. Figure 1. A chest x-ray showing a collection of blood in the right pleural cavity (outlined in red). Lungs should be black on x-ray, as on the left (blue outline) (trauma.org) 2. Abdomen: Bleeding can come from damage to any of the numerous blood vessels in the abdomen or from damage to the organs themselves, several of which are extremely well vascularised (spleen, kidney, liver). Penetrating injuries (knives, gunshots) cause direct damage to the organs they pass through. Blunt trauma can injure multiple organs simultaneously the extreme force can cause organs and blood vessels to tear and

scan to determine the extent of the damage. Figure 2 Left: penetrating knife wound to the abdomen. Right: blunt trauma after a car accident (right).

2 rupture. Patients that are unstable (falling blood pressure, increasing heart rate) will go straight to the operating theatre for surgery while stable patients can be imaged using a computed tomography (CT) scan to determine the extent of the damage. Figure 2 Left: penetrating knife wound to the abdomen. Right: blunt trauma after a car accident (right). The car has hit a stationary object and therefore decelerated rapidly. (Courtesy of RCEM Learning). Question 7: Penetrating objects like the knife in the image above should be left in place until a surgeon is present. Why? Question 8: What has caused the bruising (red diagonal strip) in the image on the right? What does this tell you about the passenger and the car crash? 3. Pelvis: The pelvis is the junction between the abdomen and the legs. It contains a bony ring structure which, when fractured, often results in damage to the veins and / or arteries within the pelvis. The entire circulating volume can be lost rapidly within the pelvis, so it is important to stabilise these injuries quickly. This can be partially achieved by tying a sheet around the legs (just below the pelvis), or using a pelvic binder. This buys time before displaced fractures can be put back in place and bleeding can be stopped by surgery.

$Figure 4. An x-ray of an "open book" pelvic fracture. The bones should join together at the red arrow. (Case courtesy of Dr Andrew Dixon, Radiopaedia.org, rid: 31718). 4. Long Bones: Contrary to popular belief, bones contain lots of blood vessels -remember bone marrow is where all the blood cells are produced.$

3 Figure 4. An x-ray of an "open book" pelvic fracture. The bones should join together at the red arrow. (Case courtesy of Dr Andrew Dixon, Radiopaedia.org, rid: 31718). 4. Long Bones: Contrary to popular belief, bones contain lots of blood vessels -remember bone marrow is where all the blood cells are produced. Fractures can cause bleeding from the bones themselves and surrounding structures, including major blood vessels. Fractures of the femur (thigh bone) are most likely to cause major haemorrhage. The initial management of these fractures should try to align the limb normally. Returning fractures too close to their normal position reduces bleeding and pain (although the reduction itself will be painful without adequate pain relief). 5. Head and Neck: Head and neck injuries are important they can be fatal or lead to long-term disability. The head is unique in that the brain is contained inside a fixed bony box the skull. While this offers significant protection against trauma, it also creates unique problems. Bleeding or swelling from a brain injury inside the skull takes up space and because the skull can t expand the pressure inside the skull increases the Monro-Kellie Doctrine. The increase in pressure can result in further brain injury by two mechanisms: it reduces blood flow to the brain (not dissimilar to what happens in stroke) and eventually it can force the brain out of the skull (almost always resulting in rapid death). Bleeding can occur from within the brain itself or into one of the layers (meninges) that surround the brain. Management after A, B, C, D, E aims to optimise blood pressure and carbon dioxide levels and prevent seizures. Further management (if possible) will require surgical relief of the pressure within the skull.

4 Figure 5. A CT scan of an epidural haematoma (red arrow). Blood collects between the skull (blue arrow) and outer meningeal layer. Normal brain tissue (yellow arrow) is then gradually compressed as bleeding and pressure inside the skull rises (trauma.org). Question 9: What are the names of the different meningeal layers? What is bleeding between each layer called? Question 10: What effect does carbon dioxide have on blood flow to the brain? The spinal cord contains (nearly) all of the nerves that control the body. Injury to the spinal cord can result in severe disability and, if the injury is near the head end of the cord, can be fatal. The diaphragm is controlled by nerves that leave the spinal cord in the neck without these nerves breathing ceases. While spinal injuries cannot be reversed immobilisation of the head and spine ensures no further damage can be done. Question 11: Nerve roots are named by the vertebrae at which they leave the spinal cord (e.g., nerves that leave the cord below the 3 rd cervical vertebra are called C3, below the second thoracic vertebra T2 etc. Which nerves control the diaphragm? Is the breathing of the patient in Figure 6 at risk?

$Figure 6. CT scan showing a fracture and dislocation of the 5th / 6th vertebrae in the neck. The blue lines indicate the location of the spinal cord.$

5 Figure 6. CT scan showing a fracture and dislocation of the 5th / 6th vertebrae in the neck. The blue lines indicate the location of the spinal cord. The red arrow indicates where the 6th vertebra has shifted backwards to cut the spinal cord. Patient was driving a car without a seatbelt and was ejected through the windscreen.

Trauma Overview. Chapter 22

Trauma Overview. Chapter 22 Trauma Overview Chapter 22 Kinematics of Trauma Injuries are the leading cause of death among children and young adults. Kinematics introduces the basic physical concepts that dictate how injuries occur