However, just the opposite can be the case. Due to the large number of nerve fibres located just under the top layer of our skin the epidermis superficial abrasions or burns will often cause more pain than a cut that may happen when working in the kitchen or workshop. Any deep puncture wounds or cuts that bleed severely should always be cared for by a doctor!
Many people tend to apply a plaster in the acute phase of the injury only, that is, just until the bleeding has stopped. Then the plaster is removed and discarded as quickly as possible in order "to let the wound breathe". Scientific studies have shown, that in most cases wound healing will proceed better and without complications if the wound is protected with a plaster until they have healed completely.
This is a myth that seems to originate from pirate and adventure novels. Even if many of us would love to believe this romantic theory: we are afraid to have to tell you that it is complete nonsense. What many people do not consider is that sea water may be severely contaminated, especially near those coast stretches - with a variety of highly unsavoury germs or chemicals "swimming" in it.
Both of which would contribute significantly to the risk of an infection and can delay wound healing. In addition, contact with water will swell the skin, which may affect the process of wound closure.
In this case, bacteria and germs may easily enter the wound and the risk of wound infection would be increased dramatically. We all know the feeling: some time after an injury, the affected area will begin to tingle and itch. This goes especially for superficial wounds.
And yes — in fact, this itching may indicate that the healing process is well on its way. But do watch out! Everyone has experienced itch, whether it be the nuisance of a mosquito bite or a transient itch on the scalp that is relieved by a simple scratch.
To address the understanding of the phys-iology of itch, an overview of the current understanding is provided, with an effort to place this understanding in the context of wounds; therapeutic approaches that may be outside of the conventional toolkit are made based on this background.
In the skin, a number of cell types can contribute to itch as a result of multidirectional communication. Beyond sensory nerves, these may include any epidermal or dermal cell with the capacity to participate in wound healing or inflammatory processes: keratinocytes, T and B cells, mast cells, basophils, eosinophils, and fibroblasts.
These cells produce a variety of cytokines and additional mediators, many of which have been linked to itch, including interleukin IL 4, IL-6, IL, IL, IL, IL, cysteine and serine proteases, nerve growth factor, the neuropeptide substance P, calcitonin gene-related peptide, and endothelin, as well as serotonin, leukotrienes, and prostaglandins.
The cell body of the afferent sensory fiber in the skin is in the dorsal root ganglion, adjacent to the spinal cord. The dendrite that leaves the ganglion synapses with second order neurons in the spinal cord. The peptides most implicated in itch at this anatomic site include gastrin- releasing peptide and brain natriuretic peptide. Instructions are then sent to motor neurons that are responsible for scratching.
This behavior may relive itch or, as a result of skin perturbations induced by scratching, contribute to the itch-scratch cycle. The sensation of itch is eventually modulated, perhaps passively, as wound healing reaches as yet undefined stages in association with remodeling or actively with the production of endogenous modulators of itch, including dynorphin, an endogenous opioid peptide. Each of the molecules listed above interact with respective cognate receptors.
In addition to these receptors, a number of ion channels, including members of the transient receptor potential TRP family, present on sensory nerve fibers and keratinocytes contribute to the multidirectional communication that occurs in the skin. While capsaicin, the chemical that provides the sensation of heat from hot peppers, interacts with the TRP subfamily V member 1 channel, the nature of endogenous ligands of such channels, other than cationic ions, is not clear.
It is not known if any pruritogens interact directly with TRP channels. Local environmental factors also contribute to itch. These may include products of the microbiome; for example, staphylococcal delta toxin, implicated in atopic dermatitis, degranulates mast cells and may contribute directly to itch. A mechanism to account for itchy scabs has been provided involving the innate immune system and the associated toll-like receptor TLR family.
These gram-positive organisms interact with TLR2, leading to activation of kallikrein proteases, which in turn can activate the protease-activated receptor 2 that is implicated in itch. The omission of histamine from the above discussion was purposeful. It was not because histamine is absent, but rather because it is now recognized that the contribution of histamine to clinical itches, other than some cases of urticaria, is, at best, modest.
Wounds may occur in the setting of any of a large number of precipitants. These wounds include those associated with genetic conditions such as epidermolysis bullosa, metabolic conditions such as diabetes, ulcers from Leishmania that result from a parasitic disease transmitted by sand flies, a vector arthropod, accidents, burns, or the trauma of surgery.
Wound healing proceeds through the phases of hemostasis, inflammation, proliferation, and remodeling. An open wound may itch but so can an area that has healed, particularly the itch associated with burns.
A large number of mediators have been implicated in itch and a large number of mediators are present in and around wounds.
It is reasonable to conclude that there will be overlap with respect to some of these mediators. It is not known which of the wound-associated mediators can induce or inhibit pruritus. The culprits also must be present in sufficient quantity at a location in the wound where a sufficient quantity of its cognate receptor also must be located. Moisture level, pH, and signaling associated with tissue tension may all contribute to itch.
People with epidermolysis bullosa simplex frequently have itchy wounds. In contrast, people who have venous ulcers do not typically have itch in their lesions and the ulcers in people with leishmaniasis do not itch. These conditions provide templates for the study of pruritoceptive itch. Likewise, the neuropathic itch that develops and persists after the healing of some surgical incisions or burns can provide a template for the study of itch versus non-itchy lesions in these conditions.
The application of the increasingly powerful approaches of proteomic and metabolic profiling to itchy and non-itchy wounds, healing and healed scars, and burns may allow for the determination of the relevant mediators. These data can then be used to develop therapies that are targeted to itch. For an unfortunate few, itching can be so severe as to cause major disability. If I could offer any simple solutions to this problem, my patients and I would be much less frustrated.
Unfortunately, the only certainty I can offer is that, first, itching is a normal response to healing and, second, it will go away with time. This latter statement is rarely received with enthusiasm, and over the years my patients and I have found a few methods that lead to temporary and partial relief. It is also an uncomfortable sensation that falls somewhere between a tickle on the one hand and a pain on the other. The nerve fibers responsible for the itch sensation have their endings right at the junction between the two layers of skin, the dermis, and the epidermis.
These nerve fibers are identical to those that conduct pain messages. So, in truth, itching is a variant of pain. The first step in treating itching is keeping the skin moist. Dry skin, especially dry burned skin, is a common cause of itching.
This problem can be easily prevented by applying skin moisturizers on a regular basis, often several times a day. We use creams that are simple in composition, avoiding those with perfumes or other additives.
Lotions should also be avoided because they contain alcohol to liquefy them, and alcohol can dry the skin. If you are among the high-risk groups, it is suggested that you go to a clinic and let the professional medical personnel assist in the cleaning and care of your wound. Hong Kong Singapore. You're changing shipping destination and will be directed to another site. Log in Or Register. Boost Sexual Health Vitality. Select Category.
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