What Is A Stab Wound

Overview 

Stab wounds are a type of penetrating trauma that can be self-inflicted or purposely inflicted by someone else. They can be induced by a wide range of things and can occur anywhere in the body.

Slash injuries, while typically inflicted by a knife, vary from stab injuries in that just the skin is normally harmed, and the process is more of a slicing or dragging motion rather than the thrusting mechanism observed in stab wounds.

Stabbing wounds accounted for more than 70% of all penetrating injuries and 6% of all trauma patients in one South African research. Patients are often young and predominantly male. Self-inflicted stab wounds are less common than those caused by others.^[1]

Causes and mechanisms 

Stab wounds are a type of penetrating trauma, this is when a foreign object pierces the skin and enters the body forming an injury. If the object pierces the skin it is called ‘’piercing trauma’’, if not then it's called ‘’blunt trauma’’. In the piercing type, the object can remain in the tissue or passes through. Stab wounds rarely have an exit wound due to the lack of energy, but some can have them, for example, an injury from an arrow.

These stab wounds usually cause internal damage by causing shock to the surrounding structures and also infection. The severity is based on the number of body organs involved.

Usually, these types of injuries are dependent on the amount of energy that is being transferred from the object to the body. This energy is dependent on how fast the object is moving and is called kinetic energy. The faster the object moves, the more damage it will cause. As the object passes through the tissue, the kinetic energy is transferred to the tissue, causing shock.

In penetrating injuries, there is also a space left behind when that object is removed from the body, and this is called a cavity. This is formed due to a pressure wave pushing the tissue out of the way. This is more characteristic of high-velocity penetrating trauma.

Apart from the above, in stab wounds, there is an association with shearing forces that are also dependent on the shape, i.e. the wound is produced by sharp, pointed objects and the direction of the object is perpendicular to the skin surface.^[1]

Types of stab wounds 

In literature, there are no specific definitions for types of stab wounds because studies are still being done on how to define them, but under a consensus, it can be presumed that stab wounds can be broken down into 2 types:

1. Superficial
2. Deep

Superficial stab wounds are injuries that do not penetrate into the cavities of the body and instead only cause damage to the skin and muscles. Usually, these stab wounds occur when the angle from which the object is entering the body is more parallel to the skin surface rather than perpendicular. As such, superficial stab wounds are not frequently noted or given importance to. Since they tend to be part of an assault, in which multiple stab wounds are present or, if present alone, are not fatal.

Comparatively deep stab wounds are wounds that penetrate into cavities and damage internal vital organs or major blood vessels. This, in turn, can lead to a person becoming unstable from loss of blood and shock, accompanied by inflammation.^[2]

Clinical presentation 

Usually, when an is stabbed, they present with an entry wound that is deeper in penetration compared to the length of an external wound. This wound can be bleeding or not. Along with the wound, the individual will also feel pain and show symptoms based on where they were stabbed in the body. To sum up, when someone is stabbed, they may have the following signs and symptoms:

• Pain
• A wound
• Bleeding
• Difficulty breathing
• Decreased urination
• Nausea and light-headedness

Stabbings, ballistic injuries, and industrial accidents are all causes of penetrating abdominal trauma. Because abdominal organs bleed profusely, these injuries may be fatal. If the pancreas is wounded, autodigestion causes more damage. Because the liver tissue has a significant blood supply, liver injuries frequently show as shock. The intestines are in danger of perforation, and the presence of faeces complicates penetration by increasing the chances of infection and a condition called sepsis. This is where the infection spreads at a very fast rate to different parts of the body and the body's immune system is overworked, leading to the immune system not being able to cope with the burden of fighting the infection.

Furthermore, peritonitis (which is the inflammation of the tissues surrounding the gut) and hypovolemic shock can result from penetrating abdominal injuries. Due to bleeding, infection, and discomfort, penetration can reduce bowel sounds. And artery damage can induce pulsating sounds that hide bowel sounds. When a doctor examines an individual with a stab wound, tapping that area (called percussion) displays hyperresonance or dullness, indicating the presence of blood or air. The abdomen may be swollen or painful, signalling the necessity for surgery.

Finally, If an individual is stabbed in the chest they can have difficulty breathing, which can lead to respiratory failure and in turn heart failure.^{[1] [3]}

Treatment

In terms of treating stab wounds, since the damage is frequently inside, this makes gross evaluation difficult. Physical examination should be followed by ultrasound, x-ray, and/or CT scanning of the patient. Before an x-ray, a paper clip is sometimes put over the entry and exit incisions.

Along with getting the necessary workup done to understand the extent of injury. Usually intravenous fluids and/or blood are administered to the patient simultaneously. Impaled things are frequently fastened in place so that they do not move and should only be removed in an operating room.

Foreign bodies, such as bullets, can be removed, but if they have the potential to cause more injury, they should be left in place. Debridement of wounds removes tissue that cannot survive and will cause infection.

But primarily, the mainstay for treatment is a laparotomy. This is the conventional treatment for penetrating abdominal injuries. In certain circumstances, enhanced imaging and a better knowledge of damage processes have resulted in conservative operating methods. This is because view towards management has been changing, especially based in whether the patient is stable or not, which in turn determines whether they will be operated on or not.^{[1] [3] [4]}

Complications and prognosis 

Patients with penetrating abdominal trauma have a varied prognosis, which is determined by the amount of injury and the timing of admission to the emergency room. The death rate is significant in the presence of extensive abdominal contamination from a ruptured internal organ, haemorrhage, multiorgan damage, concomitant head injury, or coagulopathy. 

Mortality rates remain low in individuals who are quickly resuscitated and examined. Stab wounds to the abdomen, on the other hand, typically have a considerably better prognosis than gunshot wounds.

Depending on the severity of the damage, these individuals may require rehabilitation to return to their pre-injury level of function.^[1]

Forensic implications

As mentioned, stab wounds usually mean knife injuries or gunshot wounds. in the hospital setting, this has legal implications. This means:

• The police are informed when someone arrives with such an issue.
• A person's personal information may be under scrutiny for disclosure in view of public interest and under legal obligation. The same will be informed to the patient prior, even though the medical staff will actively seek the patient's consent before disclosure.
• An individual will be asked if they want to speak to the police, and their decision will be valued. But the consequences of the same will also be explained to the individual.

Similarly, the forensic implications that are associated include:

• The individual's clothes, belongings and any fragments are retained, bagged, labelled and kept. Until the chain of custody is handed over to the police.

FAQ

What should I do if I or someone else is stabbed?

Firstly, It is important to try and remain calm. Following this, assess if you or the other person is stable by checking their pulse and consciousness. Then, call your local emergency services number to request an ambulance.

How can I tell if a stab wound is deep and has caused serious internal damage?

Unfortunately, one cannot assess if a stab wound is deep unless they are qualified to do so. If the wound has gone deep enough to damage vital organs, the individual will have symptoms of difficulty breathing, lightheadedness, pain and loss of consciousness.

What is the risk of infection with a stab wound, and how can it be prevented?

The risk for wound infection varies based on individual people, generally with an open wound the risk is higher. In order to prevent infection, it is best to go to your nearest hospital immediately if you or someone else has been inflicted with a stab wound.

What are the potential long-term complications of a deep stab wound?

Long term complications can include, loss of function of an organ or structure of the body and their associated difficulties in day to day life . For example in case of bowel injury, an individal can end up with a colostomy bag for life this can effect their quality of life. Or if a nerve is injured, it can lead to chronic pain or numbness etc.

Summary

Stab wounds are injuries that penetrate the skin of the body. They can be superficial or deep, and can cause serious damage. Such as injury to a vital organ or injury to a major blood vessel. This is further complicated by the bodies response to injury by inflammation. It is imperative that one gets emergency care when they or someone else is injured in such a way so that they can get the required treatment in time, since time is of crucial essence in these scenarios.