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Query: UMLS:C0022116 (ischemia)
 91,303 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Amputated human fingers were used to observe the morphologic changes in degeneration of Pacinian corpuscles, and postoperative moving two-point discrimination of the replanted fingers was examined to analyze sensory recovery after replantation. Normal corpuscles are composed of an axon terminal and inner and outer cores, resembling a sliced onion. The inner core is composed of thin, multilayered lamellar cells, and the outer core consists of multiple layers of thin perineurial cells. Based on our morphologic findings, following mitochondrial degeneration in the axon terminal, the terminal and inner core cells disappeared within 9 to 16 hours, but the outer core did not lose its structure until more than 24 hours after amputation. Collagen fibrils in the corpuscles appeared from 5 hours after amputation and periodically increased their amount up to 27 hours after amputation. Postoperative sensory recovery of the replanted fingers was significantly poorer with 9 hours or more of cold ischemia. These findings suggest that the inner core cells originating from Schwann cells degenerate at over 9 hours after amputation, and this may be related to the poor sensory recovery of replanted fingers. It also appears that the outer core cells originating from the perineurial cells in the amputated fingers survive even up to 27 hours after amputation and produce collagen fibrils in the extramatrix spaces of the outer core cells.
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PMID:Electron microscopic observations of degeneration of human Pacinian corpuscles in amputated fingers. 173 91

Amputated rat hindlimbs were subjected to either normothermic (26 degrees C) or hypothermic (4 degrees C) ischemia. Experimental limbs had their microcirculation washed out (either before or after the ischemic insult) with a physiologic acellular plasma substitute previously reported to enhance flap survival following extended periods of warm ischemia. Control limbs were not washed out; i.e., stagnant blood remained in these limbs. Following the ischemic interval, amputated limbs were replanted. Monastral blue B, a colloidal pigment capable of labeling leaky blood vessels, was administered systemically to all rats just prior to vascular declamping. Limb biopsies of skin and muscle were harvested 30 minutes following revascularization in order to assess Monastral labeling and, therefore, the functional integrity of the microcirculation. Results confirm that stagnant blood under conditions of warm ischemia is detrimental to the functionality of the microcirculation in both skin (p less than 0.03) and muscle (p less than 0.007). Accordingly, perfusion washout, when performed prior to the ischemic period, enhances limb survival following 6 hours of warm ischemia (p less than 0.01). Hypothermia protects against the detrimental effects of stagnant blood; perfusion offers no benefit if hypothermic conditions prevail. Physiologic mechanisms responsible for these findings are discussed.
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PMID:The role of perfusion washout in limb revascularization procedures. 365 70

In replantation surgery, it is widely accepted that replantation toxemia or muscle destruction in replanted limbs might occur after a long time of ischemia. Their possibilities are particularly high after replantation of the amputated limbs which contain more muscle tissue than tendon and bones. The present study was performed to investigate the efficacy of fluorocarbon (FC: artificial blood) perfusion to the amputated limbs in preventing these problems after replantation. The hind limbs of dogs were completely amputated at mid-thigh. Amputated limbs were divided into two groups. One was stored in ice water and the other at room temperature for six hours. Each group was furthermore divided into four subgroups. The amputated limbs were perfused with oxygenated FC or Hartmann's solution before replantation and remaining limbs were not perfused. All of them were replanted under an operating microscope. The results were as follows: Perfusion with FC had an inhibiting effect on the anaerobic metabolism in an amputated limb and also decreased the rate of death due to replantation toxemia. Perfusion with FC was effective for inhibiting leakage of creatine phosphokinase from the replanted limb and preventing muscle destruction. Both these effects were detected biochemically and histologically. The reactive hyperemia of the replanted limb usually occurred after replantation. This rate, however, was significantly decreased after replantation of the amputated limb perfusion with FC. These effects described above were more remarkable when the amputated limb was perfused continuously rather than intermittently. It is therefore reasonable to conclude that for prevention of systemic ill effect after replantation and for preservation of function of the amputated limb, continuous perfusion with FC in ice water is more effective than ice water cooling alone.
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PMID:[An experimental study of the effect of fluorocarbon perfusion for amputated limb preservation. The effect of inhibition for replantation toxemia and muscle tissue destruction]. 647 May 49

Amputated tissue maintained in a hypothermic environment can endure prolonged ischemia and improve replantation success. The authors hypothesized that local tissue hypothermia during the early reperfusion period may provide a protective effect against ischemia-reperfusion injury similar to that seen when hypothermia is provided during the ischemic period. A rat gracilis muscle flap model was used to assess the protective effects of exposing skeletal muscle to local hypothermia during ischemia only (p = 18), reperfusion only (p = 18), and both ischemia and reperfusion (p = 18). Gracilis muscles were isolated and exposed to hypothermia of 10 degrees C during 4 hours of ischemia, the initial 3 hours of reperfusion, or both periods. Ischemia-reperfusion outcome measures used to evaluate muscle flap injury included muscle viability (percent nitroblue tetrazolium staining), local edema (wet-to-dry weight ratio), neutrophil infiltration (intramuscular neutrophil density per high-power field), neutrophil integrin expression (CD11b mean fluorescence intensity), and neutrophil oxidative potential (dihydro-rhodamine oxidation mean fluorescence intensity) after 24 hours of reperfusion. Nitroblue tetrazolium staining demonstrated improved muscle viability in the experimental groups (ischemia-only: 78.8 +/- 3.5 percent, p < 0.001; reperfusion-only: 80.2 +/- 5.2 percent, p < 0.001; and ischemia-reperfusion: 79.6 +/- 7.6 percent, p < 0.001) when compared with the nonhypothermic control group (50.7 +/- 9.3 percent). The experimental groups demonstrated decreased local muscle edema (4.09 +/- 0.30, 4.10 +/- 0.19, and 4.04 +/- 0.31 wet-to-dry weight ratios, respectively) when compared with the nonhypothermic control group (5.24 +/- 0.31 wet-to-dry weight ratio; p < 0.001, p < 0.001, and p < 0.001, respectively). CD11b expression was significantly decreased in the reperfusion-only (32.65 +/- 8.75 mean fluorescence intensity, p < 0.001) and ischemia-reperfusion groups (25.26 +/- 5.32, p < 0.001) compared with the nonhypothermic control group (62.69 +/- 16.93). There was not a significant decrease in neutrophil CD11b expression in the ischemia-only group (50.72 +/- 11.7 mean fluorescence intensity, p = 0.281). Neutrophil infiltration was significantly decreased in the reperfusion-only (20 +/- 11 counts per high-power field, p = 0.025) and ischemia-reperfusion groups (23 +/- 3 counts, p = 0.041) compared with the nonhypothermic control group (51 +/- 28 counts). No decrease in neutrophil density was observed in the ischemia-only group (40 +/- 15 counts per high-power field, p = 0.672) when compared with the nonhypothermic control group (51 +/- 28 counts). Finally, dihydrorhodamine oxidation was significantly decreased in the reperfusion-only group (45.83 +/- 11.89 mean fluorescence intensity, p = 0.021) and ischemia-reperfusion group (44.30 +/- 11.80, p = 0.018) when compared with the nonhypothermic control group (71.74 +/- 20.83), whereas no decrease in dihydrorhodamine oxidation was observed in the ischemia-only group (65.93 +/- 10.3, p = 0.982). The findings suggest a protective effect of local hypothermia during early reperfusion to skeletal muscle after an ischemic insult. Inhibition of CD11b expression and subsequent neutrophil infiltration and depression of neutrophil oxidative potential may represent independent protective mechanisms isolated to local tissue hypothermia during the early reperfusion period (reperfusion-only and ischemia-reperfusion groups). This study provides evidence for the potential clinical utility of administering local hypothermia to ischemic muscle tissue during the early reperfusion period.
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PMID:Local hypothermia during early reperfusion protects skeletal muscle from ischemia-reperfusion injury. 1249 85

Major vascular injuries in extremities are rare and constitute problems for surgeons and their sequelae strongly influence remote future of the patients. The aim of study is to evaluate surgical treatment of vascular injuries in extremities and some aspects of quality of life. Since 1983 until 2002 sixty four patients with vascular limbs injuries were treated in the department. Remote evaluation has been performed in 33 persons. Severity of limb injuries was measured by Mangled Extremity Severity Score (MESS). In 20 patients (60.6%) very good and good recent results were obtained, satisfactory in 24.2% and bad results in 15.2% persons. Evaluation of functional status has been made by means of locomotion test and Jebsen-Taylor's test, social approval questionnaire, depression Beck's scale, the scale of hypochondria and by an original questionnaire to evaluate the quality of life. As considerable interdependence has been found between the functional status and the following factors: injury severity expressed in MESS (p < 0.01), clinic reception procedure (p < 0.001), ischemia time (p < 0.01), coincidence of other injuries (fractures and dislocations, muscle, tendon and nerve lesions) (p < 0.01), limb amputation (p < 0.01). Hand function significantly influences the quality of life. Patients who were in shock after trauma in the remote assessment showed susceptibility to the lowered mood and depression (p < 0.05). Quality of life is strongly connected with the features of personality, correlating mainly with the mood and tendencies of concentration upon somatic symptoms. Function of the hand influences strongly the quality of life. Amputated patients may in spite of their crippling limitations are able to adapt to everyday life.
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PMID:[Long-term results of peripheral vascular injuries in patients' limbs following reconstructive surgical procedures and influence on the quality of life]. 1720 37

Over the course of the last 60 years, microsurgical techniques, instrumentation, operating microscopes, and suture materials have all been perfected. Microsurgery training became part of the standard curriculum in plastic, orthopedic, and hand surgery programs. Despite those advances, limb replantation and transplantation are still surgical emergencies owing to limits in composite tissue viability under ischemia. Amputated parts, particularly containing large volumes of muscle, have to be revascularized within 4 hours in order to prevent permanent tissue damage. Static cold storage is the current standard to prolong ischemia time with limited success. Our research for the last 7 years has focused on extending ischemia time prior to revascularization. Our long-term goal is to make replantation and transplantation procedures elective. The following essay is the summary of our efforts.
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PMID:Advances in Limb Preservation: From Replantation to Transplantation. 3248 66