Global patient outcomes after elective surgery: prospective cohort study in 27 low-, middle- and high-income countries.

BACKGROUND: As global initiatives increase patient access to surgical treatments, there remains a need to understand the adverse effects of surgery and define appropriate levels of perioperative care. METHODS: We designed a prospective international 7-day cohort study of outcomes following elective adult inpatient surgery in 27 countries. The primary outcome was in-hospital complications. Secondary outcomes were death following a complication (failure to rescue) and death in hospital. Process measures were admission to critical care immediately after surgery or to treat a complication and duration of hospital stay. A single definition of critical care was used for all countries. RESULTS: A total of 474 hospitals in 19 high-, 7 middle- and 1 low-income country were included in the primary analysis. Data included 44 814 patients with a median hospital stay of 4 (range 2-7) days. A total of 7508 patients (16.8%) developed one or more postoperative complication and 207 died (0.5%). The overall mortality among patients who developed complications was 2.8%. Mortality following complications ranged from 2.4% for pulmonary embolism to 43.9% for cardiac arrest. A total of 4360 (9.7%) patients were admitted to a critical care unit as routine immediately after surgery, of whom 2198 (50.4%) developed a complication, with 105 (2.4%) deaths. A total of 1233 patients (16.4%) were admitted to a critical care unit to treat complications, with 119 (9.7%) deaths. Despite lower baseline risk, outcomes were similar in low- and middle-income compared with high-income countries. CONCLUSIONS: Poor patient outcomes are common after inpatient surgery. Global initiatives to increase access to surgical treatments should also address the need for safe perioperative care. STUDY REGISTRATION: ISRCTN5181700

Mechanism for formation of Hollow and Granular Silica Aerogel Microspheres from rice husk ash for drug delivery

The present work describes a method for preparation of Hollow Silica Aerogel Microspheres (HSAMs) and Granular Silica Aerogel Microparticles (GSAMs) for drug delivery, from rice husk ash (RHA), an inexpensive source of bio-compatible silica. This method involves a two-step sol-gel process for preparation of wet gel microspheres using an improved sol-gel/mineral-oil emulsion (containing dual surfactants), followed by solvent exchange and aging in aqueous ethanol, to replace water in the microspheres with ethanol. It is shown that the amount and concentration of the ammonium hydroxide (NH4OH) solution added during gelation process determine if hollow or granular wet gel particles form. A mechanism for the formation of HSAMs or GSAMs is proposed and validated by experiments. The wet gel particles are subsequently dried with supercritical carbon dioxide at 150 bar and 50 degrees C to obtain HSAMs or GSAMs. HSAMs afford high loading of drugs as illustrated by loading of 0.47 g ibuprofen per g of HSAM. Further, a fast release of ibuprofen from loaded HSAMs compared to pure crystalline ibuprofen and other loaded forms, indicates that HSAMs produced by the present method are good drug delivery vehicles. (C) 2015 Elsevier B.V. All rights reserved

Robust Silica Aerogel Microspheres from Rice Husk Ash to Enhance the Dissolution Rate of Poorly Water-Soluble Drugs

The present paper demonstrates the capability of specially prepared robust silica aerogel microspheres (RSAMs) to enhance the dissolution rate of poorly water-soluble drugs. A sol-gel/mineral oil emulsion method has been developed for RSAMs from rice husk ash (RHA), a biogenic source. The particles were characterized for their Brunauer-Emmett-Teller (BET) specific surface area, Barrett, Joyner and Halenda (BJH) pore volume and pore diameter, and morphology by optical microscopy and scanning electron microscopy (SEM). The dissolution rate of ibuprofen, a poorly water-soluble drug, was investigated by adsorbing it onto RSAMs upon dissolving it in supercritical carbon dioxide (scCO(2)) at 150 bar and 40 degrees C. This resulted in a loading of similar to 0.13 g ibuprofen/g loaded RSAMs in 24 h. X-ray diffraction analysis was used to characterize the nature of the adsorbed ibuprofen onto RSAMs. It was observed that the loaded drug on the aerogels is in amorphous form. An in vitro drug-release kinetic studies confirmed a significant enhancement in the dissolution rate, namely similar to 100% of the loaded ibuprofen released as compared to that of similar to 11% of crystalline ibuprofen in 15 min

Silica Aerogel Microparticles from Rice Husk Ash for Drug Delivery

The present work describes an improved process for preparation of silica aerogel microparticles (SAMs) for drug delivery from rice husk ash (RHA), an inexpensive source rich in biocompatible silica. The wet gel microparticles were produced by a solgel method using water-in-oil emulsion, where a mineral oil replaced vegetable oil for easy separation using less energy. Taguchi design of experiments was used to optimize the parameters controlling the solgel method. The wet gel particles were dried with supercritical carbon dioxide (scCO(2)) to obtain SAMs. They were characterized by their properties such as BET surface area, pore volume, pore diameter and morphology. The efficacy of the improved process was validated by loading a water insoluble drug, ibuprofen, and a food preservative, eugenol, in SAMs from scCO(2) medium. The release kinetics of ibuprofen and eugenol from the loaded SAMs was studied. High loading and fast release kinetics confirmed that SAMs produced by the process are suitable for drug delivery