injuries poisoning
Lacerations
Evaluation of Lacerations
Sequential steps in evaluating lacerations include the following: Finding and treating serious associated injuries Obtaining hemostasis Looking for damage to underlying structures Clinicians must find and treat Evaluation and Treatment before focusing on skin lacerations, however dramatic. Actively bleeding woundsrequire hemostasis before evaluation. Hemostasis is best obtained by direct pressure and, when possible, elevation; clamping bleeding vessels with instruments is generally avoided because of the possibility of damaging adjacent nerves. Use of topical anesthetics containingepinephrinemay also help reduce bleeding. Careful and temporary placement of a proximal tourniquet may enhance visualization of hand and finger wounds. Wound evaluation also requires good lighting. Magnification (eg, with magnifying glasses) can help, particularly for examiners with imperfect near-vision. Full wound evaluation may require probing or manipulation, and thus local anesthesia, but sensory examination should precede administration of a local anesthetic. The wound is evaluated for damage to underlying structures, including nerves, tendons, vessels, joints, and bones, as well as the presence of foreign bodies or body cavity penetration (eg, peritoneum, thorax). Failure to recognize these complications is one of the most significant errors in wound management. Nerve injuryis suggested by sensory or motor abnormality distal to the wound; suspicion is increased for lacerations near the course of significant nerves. Examination should test light touch and motor function. Two-point discrimination is useful for hand and finger injuries; the clinician touches the skin with 2 ends of a bent paper clip simultaneously to determine the minimum separation that allows perception of 2 points (usually 2 to 3 mm). Normal varies among patients and by location on the hand; the identical site on the uninjured side is the best control. Tendon injuryis suspected in any laceration over the course of a tendon. Complete tendon laceration usually causes a resting deformity (eg, foot drop due to Achilles tendon laceration, loss of normal resting finger flexion due to digital flexor laceration) because forces from antagonist muscles are unopposed. Resting deformity does not occur with partial tendon laceration, which may manifest with only pain or relative weakness on strength testing or be discovered only on exploration of the wound. The injured area should be examined through the full range of motion; the injured tendon may sometimes retract and not be visible on inspection or wound exploration when the injured area is in the resting position. Point-of-care ultrasound may also help identify tendon injuries. Vascular injuryis suggested by signs of ischemia, such as pallor, decreased pulses, or perhaps delayed capillary refill distal to the laceration (all compared with the uninjured side). Vascular injury is occasionally suspected in the absence of ischemia when a laceration traverses the territory of a major artery and is deep or complex or results from penetrating trauma. Other signs of vascular injury can include a rapidly expanding or pulsatile mass or a bruit. Bone injuryis possible, particularly after blunt trauma or when injury occurs over a bony prominence. If the mechanism or location of injury is concerning, plain x-rays are taken to rule out fracture. Foreign bodiesare sometimes present in wounds, depending on the mechanism. Wounds involving glass are likely to have foreign bodies, lacerations due to sharp metal rarely do, and wounds involving other substances are of intermediate risk. Although not very sensitive, a patient’s complaint of feeling a foreign body is fairly specific and should not be ignored. Localized pain or tenderness in a high-risk wound also is suggestive, particularly if pain worsens with active or passive motion. Wound examination and exploration are not sensitive for small foreign bodies unless the wound is superficial and its full depth is visible. Do not ignore a patient’s complaint of feeling a foreign body; although not very sensitive, this complaint is fairly specific. should be suspected when wounds near a joint are deep or involve penetrating trauma. A CT scan of the joint is highly sensitive for small volumes of intra-articular air, which indicate joint penetration ( Evaluation reference ). When in doubt, the joint may be injected with normal saline under sterile conditions. Visualization of injected fluid within an adjacent wound confirms joint penetration and such wounds should be irrigated expediently by a specialist in the operating room. Penetration of the abdominal or thoracic cavityshould be considered in any wound over those locations in which the bottom of the laceration is not clearly visible. Wounds should not be blindly probed; blind probing is unreliable and may cause further injury. Patients with suspected thoracic lacerations require a chest x-ray or other imaging study initially, with a repeat film after 4 to 6 hours of observation; any slowly developing pneumothorax should be visible by that time. In patients with abdominal lacerations, local anesthesia facilitates exploration (lacerations can be extended horizontally if necessary). Patients with wounds penetrating the fascia should be observed in the hospital; sometimes abdominal CT is used to identify hemoperitoneum. Bedside ultrasonography may also help identify injuries such as a pneumothorax, hemothorax, or hemoperitoneum, especially in unstable patients who cannot be transported to CT. Imaging studies are recommended for all wounds involving glass and for other wounds if a foreign body is suspected because of the mechanism, the symptoms, or an inability to examine the wound’s full depth. If glass or inorganic material (eg, stones, metal fragments) is involved, plain x-rays are taken; glass bits as small as 1 mm are usually visible. Organic materials (eg, wood splinters, plastic) are rarely detected with plain x-rays (although the outline of larger objects may be visible because of their displacement of normal tissue); various other modalities have been used, including ultrasonography, CT, and MRI. None of these is 100% sensitive, but CT may offer the best balance between accuracy and practicality. A high index of suspicion and careful exploration of all wounds are always appropriate. 1.Konda SR, Davidovitch RI, Egol KA: Computed tomography scan to detect traumatic arthrotomies and identify periarticular wounds not requiring surgical intervention: an improvement over the saline load test.J Orthop Trauma27(9):498-504, 2013. doi: 10.1097/BOT.0b013e31828219bc 