What are vascular Injuries?
In any injury involving blood vessels two things can happen :
- Massive bleeding or hemorrhage
- No bleeding at all or ischemia
The consequences of both are disastrous. Massive bleeding is life threatening and can kill the patient if left unrecognised. If there is no bleeding and the limb becomes ischemic it can lead to limb loss, stroke, gangrene bowel and multiple organ failure leading to the death of the patient.
How common are they?
The incidence of Vascular Trauma injury is on the increase due to fast cars (picture 1) and motorcycles, increase in violence all over the world leading to penetrating injuries in the form of gun-shot and knife wounds.
Limb injuries are mostly penetrating and may be due to violence, industrial accidents or rarely in hospitals due to vessel catheterization as in angiograms.
Sometimes the injuries are blunt but my have caused Vascular Trauma leading to the cutting of the blood supply to the concerned limb.
Of late there is a sharp increase in injury due to bomb blasts and explosions.
How does the body try to protect you?
- The vascular tree has some inherent protective properties against stretching and bending causing fewer blunt injuries to the blood vessels.
- The smooth muscle within the blood vessel protects against stretching type injury and minor puncture wounds that heal spontaneously.
- Smooth muscle within the vessel also protects against massive hemorrhage that could cause death.
- If the vessel is totally cut vascular spasm along with low blood pressure promotes clotting and helps vital organ perfusion.
- In acute stoppage of blood flow the oxygen supply to the limb or organ suffers and so anaerobic respiration takes place producing lactic acid that activates various inflammatory pathways.
- If the blood supply is not established then cell death occurs.
- If the blood supply is cut for 6 hours the muscles can recover.
- Nerves are very sensitive and short term ischemia will lead to long term numbness.
Will all be well if the blood supply is restored?
Sudden restoration of blood supply will wash the poisons accumulated in the ischemic muscles into circulation and cause myocardial depression, generalized vasodilation, severe hypotension, sepsis and even sudden death.
How do they present?
- Massive bleeding from cut vessels, needing urgent surgical exploration.
- Cold pale limb (picture 2)
- Absent distal pulses
- Expanding hematoma
In these conditions urgent surgery is needed. Cold, pulseless limb may be in a patient with low blood pressure and is not an indication for surgical exploration.
How is one sure that the blood supply has stopped when there has been no bleeding?
Just remember the six ‘Ps’ given below:
- The limb will be very Painful.
1. The limb will be very Painful.
2. The limb will be Pale or look white
3. There will be Pulseless when the doctor feels it.
4. There will be Paresis or numbness
5. There will be Paralysis or lack of movement
6. The limb will feel like Perishing with cold.
What should we do in injury cases?
If there is obvious bleeding just take a clean cloth and put pressure to control the blood loss. Get the patient to the hospital as soon as possible. Do not mess around.
What should we expect when we reach the hospital?
The first thing the doctor would do is to stop obvious bleeding and get someone to pump in fluids through the uninjured arm vein or a vein in the neck. Then he would examine the patient from head to toe. He would ask the relatives or the patient if he has any other ailment like diabetes, hypertension or heart disease.
What are the tests to be ordered?
These would include:
- Blood tests including cross matching of blood
- Chest X-Ray
- Possibly Echocardiogram
- X-ray of the limb to see if there are any fractures
- CT Scan or MRI is ordered if soft tissue injury is expected but it is not needed in most cases of Vascular Trauma injury.
- CT Angiography is generally advised provided the kidney function is not hampered. This will tell us of the anatomy of the arterial tree and the site of injury of the artery.
- Ankle-Brachial Index (ABI) is normally not done but may be done in centers where angiography facilities are not available. Here the doctor takes a normal blood pressure in the arm and compares it to the pressure in the injured leg.
- Pulse Oximeter shows the level of blood oxygen in the limb beyond the injured area. It is not very diagnostic as the patient may be in shock.
Is it possible to avoid surgery?
It is only possible in cases where there is no arterial injury or fracture and only soft tissue injury.
Will the surgery be performed immediately?
The patient has to be first stabilized by giving fluids and fully resuscitated. His cardiac condition must be improved, if it is compromised. If he is a diabetic his sugar must be brought under control. His electrolytes have to be corrected before surgery. Always remember “Life is more important than limb”. You do not want to rush into surgery and lose an unstable patient.
For how long can the limb survive?
The golden period is six hours after which the muscles of the limb start to go into irreversible damage and as time goes no it becomes progressively more difficult to save a limb.
What would be done in surgery?
If there is a fracture it has to be stabilized before the blood supply is restored. This could be by external fixation if the wound is open or an internal fixation if there is no open wound but the surgeon may prefer external fixation.
How is the blood supply restored?
This is by repair of the vessel or a bypass. The original anatomy is restored by joining the cut ends.
At times a patch may be used to cover the hole in the artery.
or if the gap is too much then a graft from the patient’s body or from outside is put between the cut ends to restore the circulation.
What should be done if there are no experts to repair the injured vessel?
If the facility of repair of the vessel is not available in your área and the centre where it is available is quite far away then an attempt to salvage can be made by doing a fasciotomy. Here the tense skin is cut to remove the pressure on the injured vessels. This is only an attempt to save the limb.
Grafts in injured vessels can get blocked, infected or bleed again despite every precaution.
Even if all goes well sometimes on restoring the circulation to the leg which has not had circulation for over 6-12 hours, the poisons may go into the blood and circulate all over the body making the patient very sick. This is called reperfusion injury and can be life threatening. There is also a strong possibility of the kidneys shutting down and the patient going on dialysis.
Is amputation a possibility?
Definitely yes! If there is much time lost before revascularization and the leg is cold, numb, blue and without movement. In such cases it may be wise to amputate the limb because ‘Life is more important than limb’.
The future of Vascular Trauma.
Vascular Trauma is one of the leading causes of death all over the world and is on the increase due to faster cars and motor cycles. That is why it is mandatory to wear seat belts and speed limits have been enforced.
What is the way forward?
Improved medical serves, faster transport, well trained and efficient paramedical staff and better and more affordable medical facilities all over the country.