Physical and Chemical Stability of Dexamethasone Sodium Phosphate in Intravenous Admixtures Used to Prevent Chemotherapy-Induced Nausea and Vomiting

Purpose: Dilute intravenous (IV) admixtures of dexamethasone sodium phosphate (DSP) are becoming increasingly used in antiemetic regimens to prevent chemotherapy-induced nausea and vomiting (CINV). Based on its chemical structure and previous studies, DSP is known to be susceptible to hydrolysis and oxidation under certain conditions. There are limited data to directly support the selection of IV diluents, storage conditions, and beyond-use dates for the dilute IV solutions of DSP used in the antiemetic regimens. This study was designed to investigate these parameters. Methods: A stability-indicating high-performance liquid chromatography (HPLC) method was first developed for the analysis of DSP. Commercially available 100 mg/10 mL DSP injection vials were used to prepare the IV admixtures of DSP in 0.9% sodium chloride injection or 5% dextrose injection. The final DSP concentrations were 0.08 or 0.4 mg/mL, which bracketed the range commonly used in antiemetic regimens. These admixtures were packaged in 50-mL polyvinylchloride (PVC) bags and stored at room temperature or under refrigeration for 14 days. Samples from each IV bag underwent visual, pH, and HPLC assessments on days 0, 1, 3, 7, and 14. Results: Immediately after preparation, the IV admixtures of DSP appeared clear, colorless, and free of particulate matters. The initial pH values were 6.4 to 6.8 and 7.0 to 7.8 for samples in 0.9% sodium chloride and 5% dextrose, respectively. The initial DSP concentrations of all samples were within 96% to 100% of the expected values. Over the 14 days of storage at room temperature or refrigeration, no significant change was observed for the visual appearance of any IV bags. The pH of all samples remained within one pH unit from the initial values. The HPLC results confirmed that all samples retained 94% to 100% of original drug concentrations and that no significant degradation products were observed. Conclusions: Intravenous admixtures of DSP at 0.08 to 0.4 mg/mL are compatible with 0.9% sodium chloride and 5% dextrose in PVC bags. These admixtures are also chemically and physically stable when stored at room temperature or under refrigeration for up to 14 days.

Significant Published Articles for Pharmacy Nutrition Support Practice in 2019

The purpose of this article is to assist the pharmacist engaged in nutrition support therapy in staying current with pertinent literature. Methods: Several clinical pharmacists engaged in nutrition support therapy compiled a list of articles published in 2019 considered important to their clinical practice. The citation list was compiled into a single spreadsheet where the author participants were asked to assess whether the article was considered important to nutrition support pharmacy practice. A culled list of publications was then identified whereby at least 5 out of the 8 author participants considered the paper to be important. Guideline and consensus papers from professional organizations, important to practice but not ranked, were also included. Results: A total of 111 articles were identified; 6 from the primary literature were voted by the group to be of high importance. An additional 9 organizational guidelines, position, recommendation, or consensus papers were also identified. The top-ranked articles from the primary literature were summarized and a narrative regarding its implications to pharmacy nutrition support practice were provided. Conclusion: We recommend that pharmacists engaged in nutrition support therapy be familiar with these articles as it pertains to their practice.

Selecting an Automated Parenteral Nutrition Compounder Device at a Tertiary Care Institute in Saudi Arabia

Background: With advances in hospital automation, selecting an automated compounding device (ACD) for compounding parenteral nutrition (PN) may be challenging. A well-designed comparative review that considers safety and technical standards could assist in the selection process. United States Pharmacopeia chapter <797> and The American Society of Hospital Pharmacists (ASHP) has provided guidance on the safety and accuracy of ACDs. Objective: Utilizing a checklist of technical and performance specifications investigators sought to assess the adequacy of compounders available in the Kingdom of Saudi Arabia. Method: Investigators compared the NutriMiX KS-240 and the Exactamix EM 2400. A literature review of practice standards, safety, technical, and performance specifications was conducted. These were developed into a checklist of 46 technical and performance specifications. Investigators evaluated each ACD using the checklist. Results: It was found that 43 (93.48%) of the technical and performance specifications, required by the hospital, were met by the NutriMix KS-240, while 39 (84.78%) were met by Exactamix EM 2400. Conclusion: This review found that although ACDs comply with the majority of standards and specifications, software integration with the hospital information system may be a limiting factor in selecting an ACD. The investigators concluded that the NutriMiX KS- 240 matches the technical and performance specifications for automated compounders required by our institution.

Evaluation of the Physical Compatibility of Intravenous Methocarbamol in Lactated Ringer's, 0.45% Normal Saline, and Plasma-Lyte A

Background: The need to determine physical compatibility of intravenous admixtures is directly related to patient safety and patient outcomes. While the provision of multi-modal analgesic strategies has increased over the past decade, a paucity of data exists regarding physical compatibility of select medications. Objectives: To evaluate the physical compatibility of methocarbamol in Lactated Ringer's (LR), 0.45% normal saline (0.45% NaCl), and Plasma-Lyte A (PLA) at concentrations of 4, 10, and 20 mg/mL. Methods: Admixtures were prepared and evaluated using previously validated methods under a laminar flow hood using aseptic technique. Samples were prepared in a triplicate manner, 3 mL aliquots were placed into polymethyl methacrylate cuvettes for evaluation at time points 0, 1, 5, 8, and 24 hours. Visual inspection of samples included assignment of a number: 0-no precipitation, 1-trace evidence of precipitation, 2-slight haze, 3-medium haze, and 4-heavy precipitation. Any evidence of precipitation was considered significant. A variable wavelength spectrophotometer set at 547 nanometers was used to measure absorbance. A change in absorbance of ±0.010 was considered significant. A change in pH of ±0.1 was considered significant. Results: No significant changes occurred relating to visual inspection or absorbance across all concentrations and time points for LR; however, there was a significant change in pH across all concentrations at hour 5. In 0.45% NaCl and PLA, no remarkable changes occurred across all concentrations and time points regarding visual observation, spectrophotometric absorbance, and pH analysis. Conclusions: Methocarbamol at concentrations of 4, 10, and 20 mg/mL is physically compatible for up to 1 hour in LR. Methocarbamol is physically compatible in 0.45% NaCl and PLA for up to 24 hours. Chemical stability tests are warranted to confirm these findings.

Physical Compatibility Between Intravenous Magnesium Sulfate and Potassium or Sodium Phosphate in a Pediatric Intensive Care Unit

Objective:To evaluate the physical compatibility between intravenous magnesium sulfate and potassium and sodium phosphate, a common electrolyte intravenous supplementation in pediatric intensive care units. Study design: Magnesium sulfate was mixed separately with potassium phosphate and sodium phosphate at ratios of 1:1, 1:4, and 4:1. Binary mixtures were prepared, in triplicate and under sterile conditions, by permuting the order of addition. The undiluted pure drugs were used as controls for possible sequence effects. Visual changes, turbidity, and pH were assessed immediately after mixing (baseline) and at 4 and 24 hours. Two observers performed visual changes by naked-eye visual inspection in order to search visible haze, particulate matter, gas formation, or color change. Turbidity was measured by nephelometry and incompatibility was defined as an increase of ≥0.5 nephelometric turbidity units (NTU) from baseline. pH was measured using a portable pH meter and incompatibility was defined as a variation of >1 pH unit during the observation period. Results: None of the admixtures exhibited visual changes or significant variations in turbidity (increases of ≥0.5 in nephelometric turbidity units) or pH (changes of >1 unit) during the observation period and neither compared with baseline. Conclusion: In this study, no visual changes were observed, and turbidity and pH evaluated by instrumental methods remained within acceptable limits and showed no significant variations from baseline, therefore no physical incompatibility between magnesium sulfate and potassium or sodium phosphate was found.

Long-Term Stability of Lorazepam in Sodium Chloride 0.9% Stored at Different Temperatures in Different Containers

Background and Objective: Infusion containing lorazepam is used by geriatric department to limit anxiety disorders in the elderly. Currently, these infusions are prepared according to demand by the nursing staff, but the preparation in advance in a centralized service could improve quality of preparation and time management. The aim of this study was to investigate the long-term stability of this infusion in polypropylene syringes stored at 5 ± 3°C. Then, results obtained were compared with stability data of lorazepam in syringes stored at room temperature, glass bottles at 5 ± 3°C, and glass bottles at room temperature. Method: Eight syringes and 6 bottles of infusion were prepared by diluting 1 mL lorazepam 4 mg in 23 mL of NaCl 0.9% under aseptic conditions. Five syringes and 3 bottles were stored at 5 ± 3°C and 3 syringes and 3 bottles were stored at room temperature for 30 days. During the storage period, particle appearance or color change were periodically checked by visual and microscope inspection. Turbidity was assessed by measurements of optical density (OD) at 3 wavelengths (350 nm, 410 nm, 550 nm). The stability of pH was also evaluated. The lorazepam concentrations were measured at each time point by high-performance liquid chromatography with ultraviolet detector at 220 nm. Results: Solutions were physically unstable in syringes at 5 ± 3°C after 4 days: crystals and a drop of OD at 350 nm were observed. However, pH was stable. After 2 days, solutions were considered as chemically unstable because a loss of lorazepam concentration higher than 10% was noticed: the lower 1-sided confidence limit at 95% was below 90% of the initial concentration. To assess temperature and polypropylene influence, results were compared with those obtained for syringes at room temperature and bottles at 5 ± 3°C and room temperature. Precipitation, drop of OD at 350 nm, and chemical instability were observed in all conditions. Conclusion: Solutions of lorazepam were unstable after 2 days in syringes at 5 ± 3°C. Preparation in advance appears, therefore, not possible for the clinical use. Storage conditions (temperature and form) do not improve the stability.