Muscle flaps can be particularly difficult to judge – color change with loss of a beefy red appearance is most common. If there is an arterial circulatory problem the flap would usually look pale and lack capillary refill. These and other factors make clinical evaluation often unsatisfying despite being the accepted gold standard in detecting replant and flap compromise.įlap circulatory disturbances can be divided into arterial insufficiency and venous insufficiency. Flaps and replants are often bled or medicinally leeched to alleviate or attempt to pre-empt venous obstruction, leaving the skin stained with blood and difficult to assess. Patients with low hemoglobin levels are pale. For instance, replanted fingers are stained with dark colored grease embedded into the skin folds and fingerprints before an accident amputated fingers. In addition, there are confounding factors that interfere with assessment by even the most experienced clinician. The examiner looks at flap color and sometimes capillary refill or temperature depending on the setting. Often it can be tricky to tell if a flap has a circulatory problem. Flaccidity indicates arterial occlusion, while swelling suggests venous obstructionĬlinical monitoring is effective, but can be difficult, and imperfect, even with the most experienced observer. Turgor in well-perfused replanted digits should approximate the turgor of normal digits. Stabbing with a needle or scalpel yields similar information, but if done repeatedly may cause significant tissue trauma. If brisk, dark bleeding occurs, venous insufficiency should be considered. If no bleeding is noted, arterial occlusion is implied. If the nail bed has been exposed, or if a wound edge or exposed tissue surface is accessible, abrasion should cause bright red bleeding. A pink color with 1-to-2-second refill is consistent with good perfusion. A rigid, blue digit with rapid refill implies venous insufficiency. A pale, cool digit without capillary refill implies an arterial inflow problem. Important physical signs include the quality of capillary filling, bleeding from a cut edge of replanted or transferred tissue, and tissue turgor. Clinical evaluation requires no specialized equipment, but does rely heavily on the experience of the evaluator. Clinical EvaluationĬlinical evaluation by an experience microsurgeon is considered the gold standard for perfusion assessment. Monitoring and quick recognition of ischemia reduces the chance of a no-reflow phenomenon and flap failure. The severity of this effect is correlated with ischemia time - the total time the flap lacks perfusion and oxygen flow. The mechanism is believed to be related to blood vessel injury, specifically endothelial injury, as well as platelet aggregation and leakage of intravascular fluid. Failure to establish re-perfusion of blood supply after blood vessel repair to an ischemic organ is known as the no-reflow phenomenon. Disruption of perfusion to a flap or replant can result in partial or complete tissue loss. To be effective, changes in perfusion need to be recognized quickly to correct any treatable problems. Monitoring circulation of flaps and replants post-operatively is critical to success in microvascular surgery. She was subsequently scheduled to undergo a revision of her total knee replacement due to suspected flexion instability with an inadequate extensor mechanism.Monitoring in Microsurgery Flap and Replant Perfusion Monitoring Several months later she experienced another episode of spontaneous dislocation during a routine office visit requiring a second ED visit for reduction under procedural sedation. Her neurovascular exam was intact pre and post-reduction. Under procedural sedation, the dislocation was reduced and placed in a knee immobilizer. Radiography revealed a posterior dislocation of her tibial prosthesis relative to her femoral prosthesis. She had a palpable dorsalis pedis pulse and brisk capillary refill. On exam, she was in obvious pain, her surgical scar was well healed, and her knee was flexed to about 90 degrees and could not be extended. Subsequently, she experienced a popping sensation and was unable to bear weight or extend the knee. While at her first outpatient physical therapy evaluation, the patient felt a pop while going from a seated to standing position. A 61-year-old female presented to the ED with acute right knee pain approximately 10 weeks after undergoing a total knee replacement for tricompartmental osteoarthritis. Emergency Department (ED) physicians should be familiar with the management of knee dislocations and complications following total knee arthroplasty. Knee dislocations can be associated with popliteal artery injuries, which are potentially catastrophic and limb threatening. Complications following knee arthroplasty are uncommon, especially dislocations. Total knee arthroplasty is one of the most commonly performed surgeries in the United States.
0 Comments
Leave a Reply. |