Tissue necrosis

Although the exact action of the thrombolytic dragp is slightly different, these drugs break down fibrin clots by converting plasminogen to plasmin (fibrinolysin). Plasmin is an enzyme that breaks down the fibrin of a blood clot. This reopens blood vessels after their occlusion and prevents tissue necrosis. 

Observe the IV site closely to detect any signs of extravasation (leakage into the surrounding tissues). Tissue necrosis can be a serious complication. Discontinue the infusion and notify the primary health care provider if disoomfort, redness along the pathway of the vein, or infiltration occurs. 

If extravasation of file IV solution should occur, local tissue necrosis (death of tissue) may be seen. If extravasation occurs, file primary health care provider is contacted immediately and file infusion slowed to a rate that keeps file vein open. 

The pretreatment of MH-susceptible patients with oral or intravenous dantrolene prior to surgery in order to avoid a crisis is controversial. Most physicians do not recommend prophylactic pretreatment except in patients who have had a previously documented episode. However, if pretreatment is desired, it is recommended that therapy be begun with intravenous dantrolene in a dose of 2 mg/Kg just prior to induction of anesthesia. This prevents the uncertainty of predictive blood values associated with the use of the oral route. The adverse effects of intravenous dantrolene prophylaxis include phlebitis and tissue necrosis. Patients who receive prophylactic treatment with oral dantrolene often complain of incapacitation, gastrointestinal irritation, prolonged drowsiness, and clinically significant respiratory muscle weakness. 

Tetanus occurs when Cl. tetani, ubiquitous in the soil and faeces, contaminates wounds, especially deep puncture-type lesions. These might be minor traumas such as a splinter, or major ones such as battle injury. At these sites, tissue necrosis and possibly microbial growth reduce the oxygen tension to allow this anaerobe to multiply. Its growth is accompanied by the production of a highly potent toxin which passes up peripheral nerves and diSuses locally within the central nervous system. It acts like strychnine by affecting normal function at the synapses. Since the motor nerves of the brain stem are the shortest, the cranial nerves are the first affected, with twitches of the eyes and spasms of the jaw (lockjaw). 

Pharmacologic neuroprotection, which might be expected to prevent tissue necrosis or apoptosis until tissue reperfusion can be achieved with rt-PA, is a theoretically attractive adjunct to rt-PA treatment. Despite positive studies in animals, all evaluations of neuroprotective agents in humans have failed. Most recently, the promising initial results for intravenous NXY-059, a ffee-radical-trapping agent, were not replicated in a confirmatory phase III trial (unpublished data). 

Santora, L. C., Krull, I. S., and Grant, K., Characterization of recombinant human monoclonal tissue necrosis factor-alpha antibody using cation-ex-change HPLC and capillary isoelectric focusing, Anal. Biochem., 275, 98,1999. 

Agents for which there are isolated case reports of local tissue necrosis. Data from ref. 36. 

Therapeutic modalities to treat extravasation events consist of specific antidotes to halt or decrease the severity of local tissue necrosis. It should be noted that only one-third of extravasation events will lead to local tissue necrosis, and most studies of antidotes are in animal models or isolated case reports. Antidotes either disperse or bind the chemotherapy agent and accelerate the removal of the agent from the tissues. Specific antidotes and their uses are presented in Table 96-16. 

Asztalos, B., J. Nemcsok, I. Benedeczky, R. Gabriel, and A. Szabo. 1988. Comparison of effects of paraquat and methidation on enzyme activity and tissue necrosis of carp, following exposure to the pesticides singly or in combination. Environ. Pollut. 55 123-135. 

IV colchicine should be avoided because it is associated with serious adverse effects (e.g., bone marrow suppression, tissue necrosis from local extravasation, disseminated intravascular coagulation, hepatocellular toxicity, and renal failure). If considered necessary, the recommended initial IV dose is 2 mg (if renal function is normal) diluted in 10 to 20 mL of normal saline administered slowly over 10 to 20 minutes in a secure, free-flowing IV line to avoid extravasation. This may be followed by two additional doses of 1 mg each at 6-hour intervals, with the total dose not exceeding 4 mg. After a full IV course, patients should not receive colchicine by any route for at least 7 days. 

Approximately 90% of patients who experience primary disease have no further clinical manifestations other than a positive skin test either alone or in combination with radiographic evidence of stable granulomas. Tissue necrosis and calcification of the originally infected site and regional lymph nodes may occur, resulting in the formation of a radiodense area referred to as a Ghon complex. 

Phenytoin is associated with pain and burning during infusion. Phlebitis may occur with chronic infusion, and tissue necrosis is likely on infiltration. Intramuscular administration is not recommended. 

We must inteiject an interesting historical sidelight at this point. Despite its reputation, thalidomide made a bit of a comeback in the 1990s (Blakeslee, 1994). Among other properties, thalidomide has been shown to have good anti-inflammatory properties, because it apparently decreases the synthesis and/or release of tissue necrosis factor. 

Lymphocytes Tissue necrosis Strenuous exercise Convulsions Tachycardia Acute hemorrhage Leukemia ... 

The tumor killing area around an electrode is circular with a radius of approximately 1 cm. Therefore the distance between the positive and negative electrode should be approximately 2 cm. Both electrodes should be inserted into the tumor, or within the peripheries of the tumor in order to avoid damage to the healthy tissue around the tumor. It is preferable to insert the positive electrode (anode) in the centre of the tumor since, in general, tissue necrosis is more pronounced around the anode rather than the cathode. For large tumors, several electrodes may be inserted in order to cover the entire tumor for the electrochemical treatment since one anode and one cathode are not effective when they are more than two cms apart. 

Carcinogenesis Mutation Terratogenesis Tissue necrosis Autoimmune response... 

Furthermore, the wide range of polymerization rates is controlled by the photoinitiation conditions. Specifically, the initiator concentration and incident light intensity control the rate of polymerization and, therefore, the rate of heat released upon curing. These conditions can be conveniently altered for in vivo applications to minimize local tissue necrosis from the... 

Concentrated sodium chloride injection Inadvertent direct injection or absorption of concentrated sodium chloride injection may give rise to sudden hypernatremia and such complications as cardiovascular shock, CNS disorders, extensive hemolysis, cortical necrosis of the kidneys, and severe local tissue necrosis (if administered extravascularly). Do not use unless solution is clear. When administered peripherally, slowly infuse through a small bore needle placed well within the lumen... 

Extravasation Extravasation of IV hypertonic solutions of sodium bicarbonate may cause chemical cellulitis (because of their alkalinity), with tissue necrosis, ulceration, or sloughing at the site of infiltration. Prompt elevation of the part, warmth, and local injection of lidocaine or hyaluronidase are recommended to prevent sloughing. 

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