Cryogen cooling during laser tissue welding was explored as a means of reducing lateral thermal damage near the tissue surface and shortening operative time. Two centimetre long full-thickness incisions were made on t...
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Cryogen cooling during laser tissue welding was explored as a means of reducing lateral thermal damage near the tissue surface and shortening operative time. Two centimetre long full-thickness incisions were made on the epilated backs of guinea pigs, in vivo. India ink was applied to the incision edges then clamps were used to appose the edges. A 4 mm diameter beam of 16 W, continuous-wave, 1.06 mu m, Nd:YAG laser radiation was scanned over the incisions, producing similar to 100 ms pulses. There was a delay of 2 s between scans. The total irradiation Lime was varied from 1-2 min. Cryogen was delivered to the weld site through a solenoid valve in spurt durations of 20, 60 and 100 ms. The Lime between spuns was either 2 or 4 s, corresponding to one spurt every one or two laser scans. Histology and tensile strength measurements were used to evaluate laser welds. Total irradiation times were reduced from 10 min without surface cooling to under 1 min with surface cooling. The thermal denaturation profile showed less denaturation in the papillary dermis than in the mid-dermis. Welds created using optimized irradiation and cooling parameters had significantly higher tensile strengths (1.7 +/- 0.4 kg cm(-2)) than measured in the control studies without cryogen cooling (1.0 +/- 0.2 kg cm(-2)) (p < 0.05). Cryogen cooling of the tissue surface during laser welding results in increased weld strengths while reducing thermal damage and operative times. Long-term studies will be necessary to determine weld strengths and the amount of scarring during wound healing.
OBJECTIVE: To describe gamma-hydroxybutyrate (GHB), flunitrazepam, and ketamine and their purported uses to facilitate acquaintance rape. Patient presentation characteristics, treatment regimens, processes to detect t...
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OBJECTIVE: To describe gamma-hydroxybutyrate (GHB), flunitrazepam, and ketamine and their purported uses to facilitate acquaintance rape. Patient presentation characteristics, treatment regimens, processes to detect the presence of the medications by toxicology screening, and methods to avoid exposure are discussed. DATA SOURCES: MEDLINE search from 1985 to 1998;additional references found within the articles;information obtained from the Internet. STUDY SELECTION: Clinical trials, reviews, and press releases concerning the use of GHB, flunitrazepam, and ketamine to facilitate acquaintance rape. Trials and reviews describing clinical effects, adverse effects, pharmacokinetics/pharmacodynamics, and usage trends were evaluated. Literature judged to be pertinent by the author was included in the discussion. DATA EXTRACTION/DATA SYNTHESIS: Reports of the use of GHB, flunitrazepam, and ketamine in acquaintance rape appear in the medical literature and lay press. Many health care professionals may not be familiar with these medications, and information about caring for patients under their influence is limited. Victims lose their ability to ward off attackers, develop amnesia, and are unreliable witnesses. Because symptoms caused by these agents mimic those of alcohol, not all victims are screened for their presence. Legislative efforts to further limit the use of or access to GHB, flunitrazepam, and ketamine have been initiated at the state and federal levels. Pharmacists should know the symptoms of exposure to the three agents;they should understand treatment regimens, methods to detect the presence of these and other drugs that may have been used in a sexual assault, and techniques individuals can use to avoid becoming victims of drug-assisted acquaintance rape. CONCLUSION: Because of their extensive drug knowledge and frequent access to patients, pharmacists are uniquely positioned to educate patients and other health care professionals about the dangers of acquaintan
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