Regional localisation of two non-specific X-linked mental retardation genes (MRX30 and MRX31)

Two genes responsible for X-linked mental retardation have been localised by linkage analysis. MRX30 maps to a 28 cM region flanked by the loci DXS990 (Xq21.3) and DXS424 (Xq24). A significant multipoint lod score of 2.78 was detected between the loci DXS1120 and DXS456. MRX31 maps to a 12 cM region that spans the centromere from DXS1126 (Xp11.23) to DXS1124 (Xq13.3). Significant two-point lod scores, at a recombination fraction of zero, were obtained with the loci DXS991 (Zmax = 2.06), AR (Zmax = 3.44), PGK1P1 (Zmax = 2.06) and DXS453 (Zmax = 3.31). The MRX30 localisation overlaps that of MRX8, 13, 20 and 26 and defines the position of a new MRX gene on the basis of a set of non-overlapping regional localisations. The MRX31 localisation overlaps the localisations of many of the pericentromeric MRX loci (MRX 1, 4, 5, 7, 8, 9, 12, 13, 14, 15, 17, 20, 22 and 26). There are now at least 8 distinct loci associated with non-specific mental retardation on the X chromosome defined, in order from pter to qter, by localisation for MRX24, MRX2, MRX10, MRX1, MRX30, MRX27, FRAXE and MRX3.

Regional localisation of a non-specific X-linked mental retardation gene (MRX19) to Xp22

A gene responsible for a non-specific form of X-linked mental retardation (MRX19) was localised by linkage analysis. Exclusions and regional localisation were made using 21 highly informative PCR-based markers along the X chromosome. Significant lod scores at a recombination fraction of zero were detected with the marker loci DXS207, DXS987 (Zmax = 3.58) and DXS999 (Zmax = 3.28) indicating that this gene is localised to the proximal portion of Xp22. Recombination between MRX19 and the flanking loci KAL and DXS989 was observed. The multipoint CEPH background map, with map distances in cM, is DXS996-1.8-KAL-19.0-DXS207-0.9-[DXS987,DXS443 ]-4.3-DXS999-3.5-DXS365-14.0-DXS989. Two other MRX disorders and two syndromal mental retardations, Coffin-Lowry syndrome and Partington syndrome, have been mapped to this region. There is a possibility that the 3 MRX disorders are the same entity. Most MRX disorders remain clustered around the pericentromeric region.

Analgesic agents in critical care

The analgesic agents most frequently employed in the critical care setting are the opioids, nonopioid analgesics, and local anesthetics. Indications for these agents are reviewed as well as their mechanisms of action, adverse reaction profiles, and available routes or methods of administration. This information can be used to ensure that the most appropriate analgesic agent is selected for the critical care patient.

Cardioplegia solutions

The mechanism of action, characteristics and components, dosage and administration, and adverse effects of cardioplegia solution are described. The pharmacist's role in the formulation, preparation, and quality control of cardioplegia solution is also discussed. The use of cardioplegia solution has substantially increased the safety of cardiac surgery. It protects the myocardium by inducing a rapid and complete diastolic arrest, minimizing myocardial energy requirements and preventing ischemic damage during the arrest phase, and minimizing or preventing reperfusion injury once coronary blood flow is restored. Chemical components added to the cardioplegia solution, such as potassium and glucose, are largely responsible for this protective effect. Basic characteristics of cardioplegia solutions include temperature, osmolarity, and pH. Crystalloid solution has traditionally been used as a vehicle for cardioplegia solution; however, laboratory and clinical studies have demonstrated favorable effects of blood-based cardioplegia solution. Single-pass and recirculating delivery systems can be used to administer either crystalloid or blood cardioplegia solutions. Pharmacists can play a major role in the formulation, preparation, distribution, and quality control of cardioplegia solutions; these solutions prevent myocardial injury during the arrest and reperfusion phases of cardiac surgery.

Management of postoperative pain by continuous epidural infusion of analgesics

The anatomy and physiology of the epidural space and the mechanism of action, sites of action, and pharmacokinetics of analgesics administered by continuous epidural infusion are reviewed, and the efficacy, adverse effects, and postoperative indications for use of analgesics administered by this route are discussed. Narcotics selectively block pain conduction by occupying specific opiate receptors in the spinal cord. Local anesthetics provide analgesia by axonal membrane blockade; they also can produce nonselective sympathetic and somatic (sensory and motor) blockade in addition to analgesia. A narcotic-local anesthetic mixture should provide an additive analgesic effect, without an increase in the incidence of adverse effects. Comparative efficacy studies have shown that continuous epidural infusions of narcotics, local anesthetics, and narcotic-local anesthetic combinations, when used appropriately, may produce better analgesia than conventional bolus methods of pain relief. Continuous epidural infusions also offer a safety advantage over intermittent epidural injections because peak and trough levels of the analgesic agent are avoided. Adverse effects of epidurally administered narcotics include respiratory depression, pruritus, urinary retention, nausea and vomiting, and sedation. Adverse effects of epidurally administered local anesthetics include urinary retention, hypotension, numbness, motor weakness, tachyphylaxis, and, rarely, systemic toxicity. The cost of epidurally administered drugs is substantially higher than that for i.m. or i.v. narcotic analgesia, but this cost may be offset by other benefits such as a shorter hospital stay. Current studies suggest superior analgesia for the majority of surgical procedures with continuous epidural analgesia infusions compared with more traditional methods of providing analgesia.

Multidisciplinary approach to improving documentation of medications used during surgical procedures

A multidisplinary approach to improving medication documentation in the operating room (OR) of a 350-bed teaching hospital is described. A committee composed of the OR pharmacy supervisor, the assistant director of nursing in charge of the ORs, and a review coordinator from the auditing department developed a medication accountability system for the OR. The system consisted of a medication use record created by the pharmacy member of the committee for each of the hospital's two ORs (main OR and eye and ear infirmary OR). The nonsterile nurse in each OR suite would complete these forms by placing check marks next to the names of the medications used. A separate medication use record was created by the chief perfusionist for use in cardiopulmonary bypass cases; this form would be completed by the perfusionist at the end of each major heart case. Once the forms were approved by the form committee, inservice-education programs were conducted for nursing and perfusion staff members; the system was implemented in both OR areas in November 1986. Errors made in completing these forms were addressed by further inservice education and individual instruction. The new accountability system was effective in improving medication documentation in the OR. Immediately after implementation of the system, 83% of medications were accounted for on the forms; after six months that figure was 90%. Before the system was implemented, only 23% of patient charts reviewed contained no errors in documentation; after six months that figure had improved to 71%. The improved medication documentation allowed for more consistent collection of the assessed pharmacy charges on bills audited by third-party payers.(ABSTRACT TRUNCATED AT 250 WORDS)

Albumin/hetastarch drug utilization review in an operating room pharmacy

A prospective drug utilization review (DUR) was performed on the colloids albumin 5% and hetastarch 6% at the University of Illinois Hospital Operating Room Pharmacy. This DUR's purpose was to evaluate the usage patterns of the two colloids. With the addition of hetastarch 6% to the formulary, an alternative colloid was available that could be therapeutically substituted for albumin 5% at a cost savings. Its usage, however, was not what would have been expected. Usage information was obtained by placing utilization forms inside the individual boxes of albumin 5% and hetastarch 6%. These forms were completed by the anesthesiologists and returned to the pharmacy, where the remainder of each form was completed. It was concluded that 93 percent of the patients administered albumin 5% could have received hetastarch 6%. Hence, potential yearly savings of approximately $12,346.00 could be realized by the Department of Pharmacy.

Lung lipid metabolism and surface tension phenomena following pulmonary embolism

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