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D Stack

Publications and source records attributed to D Stack.

4 recordsLinked to original sources
PubMed2003

Optimizing the dose of intrathecal morphine in older patients undergoing hip arthroplasty.

UNLABELLED: Intrathecal (IT) morphine provides excellent postoperative analgesia but may result in many side effects, including postoperative nausea and vomiting, pruritus, and respiratory depression, particularly at larger doses. Older patients may be at particular risk. The optimal dose of spinal morphine in older patients undergoing hip arthroplasty is not known. We designed this prospective, randomized, controlled, double-blinded study to evaluate the analgesic efficacy and side effect profile of 50-200 microg of IT morphine in older patients undergoing elective hip arthroplasty. Sixty patients older than 65 years undergoing elective hip arthroplasty were enrolled. Patients were randomized to receive spinal anesthesia with 15 mg of bupivacaine and IT morphine in four groups: 1). 0 microg, 2). 50 microg, 3). 100 microg, and 4). 200 microg. IT morphine 100 and 200 microg produced effective pain relief and decreased the postoperative requirement for morphine compared with control. IT morphine 50 microg did not provide effective pain relief. Both 100 and 200 microg of IT morphine provided comparable levels of postoperative analgesia. There were no between-group differences in postoperative nausea and vomiting, sedation, respiratory depression, or urinary retention. Pruritus was significantly more frequent with 200 microg of IT morphine. In conclusion, 100 microg of IT morphine provided the best balance between analgesic efficacy and side effect profile in older patients undergoing hip arthroplasty. IMPLICATIONS: The dosage of intrathecal morphine that provides the best balance between analgesic efficacy and side effect profile in the older patient undergoing hip arthroplasty is not known. This prospective, randomized, controlled, double-blinded clinical trial demonstrates that a dose of 100 microg of intrathecal morphine provides the best balance between efficacy and side effects, compared with doses of 0, 50, and 200 microg of morphine, in this patient population.

Aged↗
PubMed1996

Production of a high-affinity monoclonal antibody specific for 7-(benzo[alpha]pyren-6-yl) guanine and its application in a competitive enzyme-linked immunosorbent assay.

Molecular dosimetry of depurinating DNA adducts of benzo[alpha]pyrene (BP) is a promising new approach to measurement of cancer risk associated with exposure to polycyclic aromatic hydrocarbons (PAH). Depurinating adducts of BP are spontaneously released from DNA and can be detected in urine. As a first step toward developing a monoclonal antibody (MAb)-based molecular dosimetry for depurinating DNA adducts of BP, a MAb (MAb CB53) has been produced with high specific affinity for 7-(benzo[alpha]pyren-6-yl)guanine (BP-6-N7Gua), a major depurinating adduct of BP. Production of this MAb was dependent on the successful synthesis of an effective immunogen consisting of the hydrophobic BP-6-N7Gua coupled to carrier protein via a rigid spacer arm. A competitive enzyme-linked immunosorbent assay (ELISA) for BP-6-N7Gua has been developed with MAb CB53 and has been applied to evaluation of MAb binding and to quantitation of BP-6-N7Gua in a biological sample. The MAb binds with high affinity to BP-6-N7Gua (Ka = 1.4 x 10(8) M-1) and to BP-6-N7Ade (Ka = 0.7 x 10(8) M-1), another major depurinating DNA adduct of BP, but discriminates well between BP and BP-6-N7Gua. BP-6-N7Gua produces 50% inhibition at 750 fmol in the competitive ELISA, whereas BP produces 50% inhibition at 960 000 fmol. Binding affinities to selected PAH, BP-DNA adducts, and BP metabolites indicate significant contributions of the hydrophobic region C-3, C-4, and C-5 of BP and the polar oxygen of guanine to MAb/adduct binding. In a preliminary test of the utility of the competitive ELISA for quantitation of BP-6-N7Gua in urine samples, the assay (sensitivity: 200 fmol per well) produced an accurate determination of the adduct added to normal human urine.

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