Article

Prolonged duration local anesthesia with lipid-protein-sugar particles containing bupivacaine and dexamethasone.

Department of Pharmaceutical Sciences, University of Ferrara, Ferrara, Italy.
Journal of Biomedical Materials Research Part A (Impact Factor: 2.84). 12/2005; 75(2):458-64. DOI: 10.1002/jbm.a.30443
Source: PubMed

ABSTRACT Glucocorticoids prolong block duration from polymeric microspheres containing bupivacaine, but not from unencapsulated drug. Here we investigate this effect applies to particles with much more rapid drug release and improved long-term biocompatibility. Male Sprague-Dawley rats were given sciatic nerve blocks with 75 mg of 3% or 60% (w/w) dipalmitoylphosphatidylcholine (DPPC) spray-dried lipid-protein-sugar particles (LPSPs) containing 10% (w/w) bupivacaine and 0%, 0.05%, or 0.1% (w/w) dexamethasone. Sensory nerve block from bupivacaine-containing 3% and 60% (w/w) DPPC particles without dexamethasone yielded blocks lasting 301 +/- 56 and 321 +/- 127 min, respectively. Addition of 0.05% (w/w) dexamethasone increased block durations to 610 +/- 182 and 538 +/- 222 min, respectively; increasing dexamethasone loading to 0.1% did not further increase duration. One day after injection, dexamethasone-containing particles resulted in lower inflammation scores and capsule thickness than dexamethasone-free particles, but the difference was gone by day 4. Excipient composition had prominent effects at all time points. For all groups, inflammation was largely resolved by 2 weeks after injection. Dexamethasone approximately doubled the duration of nerve block from bupivacaine-loaded LPSPs, while maintaining excellent biocompatibility. Such formulations could be useful in clinical applications when nerve blockade is needed for 24 hours or less.

0 Bookmarks
  • [Show abstract] [Hide abstract]
    ABSTRACT: Drying is a commonly used technique for improving the product stability of biotherapeutics. Typically, drying is accomplished through freeze-drying, as evidenced by the availability of several lyophilized products on the market. There are, however, a number of drawbacks to lyophilization, including the lengthy process time required for drying, low energy efficiency, high cost of purchasing and maintaining the equipment, and sensitivity of the product to freezing and various other processing-related stresses. These limitations have led to the search for next-generation drying methods that can be applied to biotherapeutics. Several alternative drying methods are reviewed herein, with particular emphasis on methods that are commonly employed outside of the biopharmaceutical industry including spray drying, convective drying, vacuum drying, microwave drying, and combinations thereof. Although some of the technologies have already been implemented for processing biotherapeutics, others are still at an early stage of feasibility assessment. An overview of each method is presented, detailing the comparison to lyophilization, examining the advantages and disadvantages of each technology, and evaluating the potential of each to be utilized for drying biotherapeutic products. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci.
    Journal of Pharmaceutical Sciences 06/2014; · 3.13 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Patients with fracture femur experience severe pain on movement during positioning for spinal anaesthesia. Fascia Iliaca Compartment Block (FICB) has been used effectively for providing analgesia during positioning of the patient for spinal anaesthesia.
    Journal of Clinical and Diagnostic Research 07/2014; 8(8):5-8.
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: This paper describes the preparation of poly(DL-lactide-co-glicolide) (PLGA) nanocapsules as a drug carrier system for the local anesthetic bupivacaine. The system was characterized and its stability investigated. The results showed a size distribution with a polydispersity index of 0.12, an average diameter of 148 nm, a zeta potential of -43.5 mV and an entrapment efficiency of 75.8%. The physicochemical properties of polymeric nanocapsule suspensions (average diameter, polydispersity, zeta potential and drug association efficiency) were evaluated as a function of time to determine the formulation stability. The formulation did not display major changes in these properties over the time, and it was considered stable up to 120 days of storage at room temperature. The results reported here which refer to the initial characterization of these new formulations for the local anesthetic bupivacaine show a promising potential for future in vivo studies.
    Journal of the Brazilian Chemical Society 12/2009; 21(6):995-1000. · 1.25 Impact Factor