Copperhead snakes are endemic in certain parts of North America. They are classified as venomous pit vipers. and usually cause only local tissue changes like edema, pain, and tenderness. Rarely more severe manifestations may be seen. The diagnosis is made by identifying the snake and establishing the severity of envenomation. Observation and supportive care are sufficient, while antivenom administration is rarely indicated.
In virtually all patients, the clinical presentation comprises pain at the site of the bite, which should be clearly visible during the physical examination. It is always accompanied with swelling and erythema of local tissue . The bite occurs on the extremities in most cases, with hands and feet being the most common sites. Proximal lymphadenopathy, ecchymosis or development of either serous or hemorrhagic bullae may develop, which is typical for snakes with more potent venoms, but these symptoms are rare with copperhead bites. Very rarely, patients develop symptoms of severe envenomation, which includes systemic symptoms such as hypotension, vomiting, and dyspnea.
Identifying the snake is the first step in the diagnostic workup. Patient history should include as many details as possible regarding the appearance of the snake and a timeline should be established. Laboratory tests, including complete blood count (CBC), evaluation of serum fibrinogen, prothrombin time (PT) and activated partial thromboplastin time should be performed .
When evaluating the severity of envenomation, the following criteria should be used :
The vast majority of copperhead bites are classified into the category of minimal envenomation . However, some reports suggest that there are increasingly higher rates of copperhead bites that are either moderate or severe, which has a significant impact on the choice of therapy .
Because snake bites can be fatal and patients cannot fully explain which snake was responsible for the bite, initial management requires several emergency care procedures that will be able to support the patient in case they develop severe symptoms. Obtaining blood pressure levels, ensuring adequate ventilation and oxygen saturation, together with proper wound care should be performed while attempting to find out which snake bit the patient.
Treatment of snake bites, in general, comprises administration of antivenom and is used in all patients who experience either moderate or severe envenomation. Sheep or equine-derived antivenin has been recommended and often administered after snake bites, and the amount of prescribed antivenin depends on the severity of tissue injury and presumed envenomation . However, because copperheads cause mild toxicity in the majority of cases and very rarely pose a life-threatening risk to the patient, its use has been deemed to be unnecessary by many studies . The necessity of laboratory tests has been questioned as well . Furthermore, antivenin administration has also been contraindicated due to potentially severe allergic reactions that may occur, and thus cause more harm than benefit, while observation and supportive care is termed to be sufficient for treatment of copperhead bites. In rare cases, surgical treatment has been indicated due to extensive tissue destruction and necrosis and procedures such as debridement, fasciotomy, or even digit amputation may be performed. Supportive therapy with non-steroid anti-inflammatory drugs (NSAIDs) should be instated in all patients to cope with pain that may be quite severe.
Copperhead bites cause only local effects in the vast majority of cases and rarely progress to systemic effects, while certain studies have identified that a portion of copperheads are actually "dry bites", i.e. no venom has been released during the bite. Other studies, however, have established that the number of patients with minimal symptoms has decreased with a corresponding increase in the number of patients with more severe effects of the venom. Overall death due to snakebites in the United States are very rare , but complications such as the development of compartment syndrome, severe hematuria, diarrhea, and other systemic effects have been documented, which can lead to fatal outcomes .
Agkistrodon contortrix, also known as copperhead, is a venomous snake that belongs to the group of pit vipers, together with rattlesnakes and moccasins, which are responsible for the majority of deadly snake bites in the US. There are five subspecies of Agkistrodon contortrix :
Copperheads can be distinguished from other snakes by several characteristic features. In general, pit vipers can be identified by their triangular (arrowhead-shaped) heads, elliptical or catlike pupils, retractable fangs and heat-sensing pits that are located between the nose and the eyes, which serve to sense predators and prey. They are usually tan to brown in color. Copperheads are distinguished from other pit vipers because of their copper-colored head, and juvenile copperheads have distinct bright yellow tail tips. They measure about 70 cm in length.
Copperheads are predominantly found in the United States and are responsible for about 40% of all snakebites in this part of the world according to epidemiological studies . States that have been reported as endemic sites include Texas, South Carolina, Kansas, Alabama, as well as other states belonging to the South-Eastern part of the US. Copperheads can live in various habitats, including forests, swamps, and hillsides. They can readily change their environment. Their bites are more frequent on the extremities during the warm summer months. A majority of patients are reported to be young male adults as they attempt to deliberately get in contact with the snakes .
The copperhead venom does not always cause significant damage as often the bites are warning or "dry" bites with little or no venom. Several mechanisms of action of their poisonous bites have been reported. The majority of snake venoms interfere with normal coagulation and capillary permeability. Copperhead venom is known to induce degradation of several parts of the coagulation system, including fibrinogen . As a result, local vascular damage occurs and causes either extravasation or pooling of blood in the capillaries leading to edema and erythema. However, progression of symptoms rarely occurs with copperhead bites, as their venom is not as potent. Interestingly, contortrostatin, the venom of the southern copperhead has shown anticarcinogenic properties in animal models through preventing both cellular adhesion and angiogenesis , which implies that this compound may be used for the synthesis of novel chemotherapeutic agents.
Copperhead bites are not life-threatening, but they may cause significant local injury, which is why appropriate preventive steps may profoundly reduce the number of snake bites. Snake manipulation and attempts to get in direct contact in the open environment should be absolutely avoided. If traveling to areas that are known to be a habitat for snakes, snake bite kits may be useful and effective in providing field care, while other measures may include wearing clothes and footgear that fully cover the skin.
Copperheads (Agkistrodon contortrix) belong to the group of pit vipers, which are venomous snakes that have several distinguishing characteristics, such as arrowhead-shaped heads, retractable fangs, catlike pupils and heat-sensing pits between the nose and the eyes. Their name stems from the appearance of their copper-colored head . Although they are classified together with other pit vipers such as rattlesnakes and water moccasins, whose bites may be deadly, copperheads rarely cause severe envenomation. copperhead bites account for a small proportion of venomous bites in the Americas, where their primary habitat is, specifically the states near the South and the East coasts. Clinical presentation in individuals who are bitten includes local tissue swelling, skin induration, and pain that is often severe as a result of venom-induced vascular damage. Presumably, copperheads release venom that degrades fibrinogen and disturbs the normal coagulation process. Additionally, ecchymoses may appear in some cases. More severe local and systemic manifestations, such as compartment syndrome, marked skin reaction with the development of bullae, hypovolemia and shock are very rare with copperhead bites, although they have been reported. To diagnose a copperhead bite, an attempt should be made to identify the snake through patient history, as well as information regarding the time of bite, history of previous bites and allergies to horse or sheep products because of a possible allergy to antivenom therapy. However, administration of antivenom is rarely recommended, as there is a resolution of symptoms within a few days with supportive therapy alone . Some studies have indicated that residual injury may be significantly prolonged, while surgical therapy may be indicated in the case of compartment syndrome. There is controversy regarding administration of antivenom therapy in the case of copperhead bites, but so far, the majority of reports indicate that it might cause more harm than benefit.
Copperheads are snakes that primarily reside in South-Eastern parts of the United States and comprise a significant proportion of all snake bites that occur in the US. Copperheads belong to the group of pit vipers and their name stems from their copper-colored head. Although they are considered to be venomous snakes, they rarely cause life-threatening symptoms in patients. Like all snake bites, they are most likely to occur among young adults who are attempting to get in contact with the snake in the open environment, with male individuals usually presenting in higher numbers than women. The venom released by the snakes causes local tissue damage due to degradation of products that are important for blood coagulation and normal blood flow, which is why symptoms such as redness and swelling of local tissue occur in virtually all cases. Pain is universally present, while other symptoms such as skin rash, hypotension, breathing difficulties and other signs of systemic effects are very rare with copperhead bites. To establish a correct diagnosis, patients should try to remember the exact appearance of the snake. Copperhead, like all pit vipers, can be distinguished by their triangular (arrowhead-shaped) heads and catlike pupils. They also have fangs that can retract, which can sometimes remain in the skin of the infected individual. In the majority of cases, snake bites are treated with antivenin, a compound used to antagonize the effects of the venom, but for copperhead bites, antivenin is rarely indicated. Simple supportive care consisting of wound and pain management is sufficient in the majority of patients. Overall, copperheads pose little risk to individuals, but they might be confused with other pit vipers that can cause fatal bites, which is why avoiding snakes in the environment is highly recommended.