Fatal microvascular pulmonary emboli from precipitation of a total nutrient admixture solution

Physical and Chemical Compatibility of Medications Commonly Used in Critically Ill Patients With Balanced Crystalloids: A Systematic Review

OBJECTIVE

Evaluate available evidence of physical and/or chemical compatibility of commonly used medications in critically ill patients with balanced crystalloids.

DATA SOURCES

Ovid MEDLINE, Embase, Cochrane Central Register of Controlled Trials, and Cochrane Database of Systematic Reviews were queried from inception to September 2022.

STUDY SELECTION AND DATA EXTRACTION

This review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. English-language studies reporting physical and/or chemical compatibility data between 50 selected medications and balanced crystalloids were included. A previously designed tool to assess risk of bias was adapted for use.

DATA SYNTHESIS

Twenty-nine studies encompassing 39 (78%) medications and 188 unique combinations with balanced crystalloids were included. Combinations included 35 (70%) medications with lactated Ringer's, 26 (52%) medications with Plasma-Lyte, 10 (20%) medications with Normosol, and one (2%) medication with Isolyte. Studies commonly evaluated physical and chemical compatibility (55.2%). More medications were evaluated via Y-site than admixture. Incompatibilities were identified in 18% of combinations comprising 13 individual drugs.

RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE

This systematic review evaluates the compatibility of select critical care medications with balanced crystalloid solutions. Results may be used as a tool to guide clinicians on balanced crystalloid compatibility, potentially increasing ubiquitous use and reducing patient exposure to normal saline.

CONCLUSION AND RELEVANCE

Data are limited regarding chemical/physical compatibility of commonly used medications in critically ill patients with balanced crystalloids. Additional compatibility studies are warranted, particularly methodologically rigorous studies assessing Plasma-Lyte, Normosol, and Isolyte. Of the evaluated medications, there was a low frequency of incompatibilities with balanced crystalloids.

Proinflammatory mediators in lipid emulsions and parenteral nutrition-associated liver disease: Review of leading factors

Lipid injectable emulsions have been in clinical use for over 60 years. The first product launched was Intralipid, which consisted of an emulsion of soybean oil in water for intravenous administration. It was a key source of essential fatty acids and an alternative source of energy for patients with gastrointestinal dysfunction requiring long-term parenteral nutrition. With clinical experience, a condition known as parenteral nutrition-associated liver disease (PNALD), or intestinal failure-associated liver disease (IFALD), was observed, with a focus on carbohydrate and fat energy. Modifying the daily doses and infusion rates had some salutary effects, but PNALD persisted. Subsequently, on closer inspection of the fatty acids profile and phytosterol concentrations, degradation products arising from chemical and physical stability issues of the available lipid injectable emulsions were implicated. Recently, the US Food and Drug Administration convened an online workshop entitled "The Role of Phytosterols in PNALD/IFALD," with an emphasis on (1) the multifactorial pathophysiology of PNALD/IFALD, (2) risk associated with phytosterols, and (3) regulatory history. The scope of this review includes the multifactorial pathophysiology of PNALD/IFALD as it relates to the pharmaceutical aspects of the various lipid injectable emulsions on the market, with respect to potential proinflammatory components, as well as physical and chemical stability issues that may also affect products' safe intravenous administration to patients.

In-vitro modeling of intravenous drug precipitation by the optical spatial precipitation analyzer (OSPREY)

Intravenous (IV) administration of poorly water-soluble small molecule therapeutics can lead to precipitation during mixing with blood. This can limit characterization of pharmacological and safety endpoints in preclinical models. Most often, tests of kinetic and thermodynamic solubility are used to optimize the formulation for solubility prior to infusion in animals, but these do not capture the dynamic precipitation processes that take place during in-vivo administration. To better capture the fluid dynamic processes that occur during IV administration, we developed the Optical Spatial PREcipitation analYzer (OSPREY) as a method to quantify the amount and size of compound precipitates in whole blood using a flow-through system that mimics IV administration. Here, we describe the OSPREY device and its underlying imaging processing methods. We then validate the ability to accurately segment particles according to their size using monodisperse suspensions of microspheres (diameter 50 to 425 µm). Next, we use a tool compound, ABT-737, to study the effects of compound concentration, vessel flow rate, compound infusion rate and vessel diameter on precipitation. Finally, we use the physiological diameter and flow rate of rat femoral vein and dog saphenous vein to demonstrate the potential of OSPREY to model in-vivo precipitation in a controlled, dynamic in-vitro assay.

Exploring a case of incompatibility in a complex regimen containing Plasma-Lyte 148 in the pediatric intensive care

BACKGROUND

In the local pediatric intensive care unit, precipitation was observed in the intravenous catheter upon co-administration of four drugs together with the buffered electrolyte solution (Plasma-Lyte 148, Baxter). Co-infusion of incompatible combinations represents a safety concern.

AIMS

To reproduce the clinical case of precipitation. To further explore and understand the risk of precipitation, different combinations of the components as well as the corresponding electrolyte solution with 5% glucose (Plasma-Lyte 148 with 5% glucose) should be investigated.

METHODS

Physical compatibility of fentanyl, ketamine, midazolam, and potassium chloride was tested in combination with the buffered electrolyte solutions. The concentrations and infusion rates representative of children 10-40 kg were used to estimate mixing ratios. Analyses detecting visual particles (Tyndall beam) and sub-visual particles (light obscuration technology) were undertaken. Measured turbidity and pH in mixed samples were compared with unmixed controls.

RESULTS

Both midazolam and ketamine showed formation of visual and sub-visual particles upon mixing with Plasma-Lyte 148, respectively. Particle formation was confirmed by increased turbidity and a distinct Tyndall effect. pH in mixed samples mirrored the pH of the buffered electrolyte, suggesting that the solubility limits of midazolam, and in some ratios also ketamine, were exceeded. Midazolam also precipitated in combination with the glucose-containing product that held a lower pH, more favorable for keeping midazolam dissolved.

CONCLUSIONS

Replication of the case revealed that both midazolam and ketamine contributed to the precipitation. Midazolam and ketamine were both evaluated as incompatible with the buffered electrolyte solution and midazolam also with the buffered electrolyte-glucose solution and should not be co-administered in the same i.v.-catheter line. Fentanyl and potassium chloride were interpreted as compatible with both buffered electrolytes.

Metrology in health: challenges and solutions in infusion therapy and diagnostics

The significance of Metrology in infusion therapy and diagnostics, both critical in health care safety and quality, is discussed in this article. Although infusion therapy is the most used form of drug administration, infusion errors are often made with reported dramatic effects in different applications, especially in neonatology. Adverse incidents, morbidity, and mortality have often been traced back to poor or inaccurate dosing. For critical infusion applications to vulnerable patients, well-controlled medication administration might be accomplished by improved dosing accuracy, traceable measurement of volume, flow, and pressure in existing drug delivery devices and in-line sensors operating at very low flow rates. To this end, the contribution of recently upgraded metrological infrastructures in European Metrology Institutes to a safer infusion therapy in health care is described in detail. Diagnostics, on the other hand is a sector characterized by rapid developments further triggered recently by the necessity for the management and prevention of infectious diseases like COVID-19. In this context, the impact of metrology in future large-scale commercialization of next generation diagnostics (e.g., point-of-care) is highlighted. Moreover, the latest contributions of Metrology in the development of traceable testing methods and protocols to ensure the sensitivity and accuracy of these devices are described.

Frequently acquired drugs in neonatal intensive care and their physical compatibility

AIM

Incompatibility of intravenous drugs is dangerous and therefore undesirable. The aim of this study was to identify the most commonly acquired intravenous drugs in five neonatal intensive care units and test these for compatibility.

METHODS

The most frequently acquired drugs in five key hospitals in the South-Eastern district of Norway for 2019 and 2020 served as a proxy for the prevalence of use. Representatives were selected from the three most prevalent groups based on the Anatomical Therapeutic Chemical classification system. Co-administration of drug pairs was simulated using clinically relevant concentrations and infusion rates representing mixing ratios in the catheter. Particle formation was assessed by particle counting and size measurement, by visual examination using Tyndall beam, by turbidity and by measuring pH of mixed samples.

RESULTS

The most frequently acquired drug groups were anti-infectives, neurological agents and cardiovascular drugs. Compatibility testing revealed that both ampicillin and benzylpenicillin were incompatible with morphine. Flecainide and fluconazole showed no signs of incompatibility with morphine. No information on these combinations in a neonatal-relevant setting is available.

CONCLUSION

We recommend to abstain from co-administering ampicillin and benzylpenicillin with morphine in neonatal intensive settings. Morphine co-administered with flecainide and fluconazole in neonatal patients were evaluated as safe.

An Effective Strategy to Develop Potent and Selective Antifungal Agents from Cell Penetrating Peptides in Tackling Drug-Resistant Invasive Fungal Infections

The high mortality rate of invasive fungal infections and quick emergence of drug-resistant fungal pathogens urgently call for potent antifungal agents. Inspired by the cell penetrating peptide (CPP) octaarginine (R8), we elongated to 28 residues poly(d,l-homoarginine) to obtain potent toxicity against both fungi and mammalian cells. Further incorporation of glutamic acid residues shields positive charge density and introduces partial zwitterions in the obtained optimal peptide polymer that displays potent antifungal activity against drug-resistant fungi superior to antifungal drugs, excellent stability upon heating and UV exposure, negligible in vitro and in vivo toxicity, and strong therapeutic effects in treating invasive fungal infections. Moreover, the peptide polymer is insusceptible to antifungal resistance owing to the unique CPP-related antifungal mechanism of fungal membrane penetration followed by disruption of organelles within fungal cells. All these merits imply the effectiveness of our strategy to develop promising antifungal agents.

Co-administration of drugs with parenteral nutrition in the neonatal intensive care unit-physical compatibility between three components

There is a lack of compatibility data for intravenous therapy to neonatal intensive care unit (NICU) patients, and the purpose of this study was to contribute with documented physical compatibility data to ensure safe co-administration. We selected Numeta G13E, the 3-in-1 parenteral nutrition (PN) used at our NICU, together with the frequently used drugs morphine, dopamine and cefotaxime in two- but also three-component combinations. Incompatibility may lead to particle formation (precipitation) and oil-droplet growth (emulsion destabilisation), both which are undesirable and pose a safety risk to already unstable patients. We assessed potential particle formation of three mixing ratios for each combination (always including 1 + 1 ratio) using light obscuration, turbidity and pH measurements combined with visual inspection by focused Tyndall beam. Potential droplet-growth and emulsion destabilisation was assessed by estimating PFAT5 from droplet size measurements and counts, mean droplet diameter and polydispersity index from dynamic light scattering, and pH measurements. Mixed samples were always compared to unmixed controls to capture changes as a result of mixing and samples were analysed directly after mixing and after 4 h to simulate long contact time. None of the samples showed any sign of precipitation, neither in the drug-drug nor in the two- or three-component mixture with PN. Neither did we detect any form of emulsion destabilisation.

CONCLUSION

Dopamine, morphine and cefotaxime were found to be compatible with NumetaG13E, and it is safe to co-administer these drugs together with this PN in NICU patients.

WHAT IS KNOWN

• The need for co-administration of drugs and complex PN admixtures occurs frequently in NICU due to limited venous access. • Available compatibility data are scarce and for combinations of more than two components non-existent.

WHAT IS NEW

• Here we report physical compatibility data of two- as well as three-component combinations of frequently used NICU drugs and a 3-in-1 PN admixture. • Co-administration of Numeta G13E with dopamine and morphine, but also with morphine and cefotaxime is safe in NICU.

Physicochemical Stability and Compatibility Testing of Voriconazole in All-in-One Parenteral Nutrition Admixtures

(1) Drug compatibility with all-in-one (AiO) parenteral nutrition (PN) admixtures is a very important pharmaceutical quality issue to be answered based on appropriate laboratory testing. We assessed voriconazole (V), a poorly water-soluble (logP ≈ 1) single-daily dosed antifungal drug monitored in patients and thus candidate for AiO PN admixing for convenient and safe patient care. We evaluated V compatibility and stability in AiO PN admixtures through adapted therapeutic drug monitoring method (drug stability) and visual microscopic emulsion stability by lipid droplets analysis improved by an automated microscopic digital assessment. (2) V was added in concentrations of 0.05/0.25/0.5 mg/mL (143.1/715.7/1431.5 µM), correlating to daily therapeutic dosing, to three commercially available industrial AiO PN admixtures. Three aliquots were stored in the refrigerator (4 °C), at room temperature (24 °C) and under stress conditions in a water bath (37 °C). Samples taken at 0/24/48/72/168 h after admixing were subjected to a stability-indicating one-week analysis. Assessment included visual examination, lipid droplet measurement according to an established and validated method (bright-field microscopy using oil immersion), pH measurement (glass electrode) and V identification/quantification (LC–MS/MS). (3) After one week, all samples at 37 °C showed slight yellow discoloration. The pH values remained stable. All samples met specifications for lipid droplets according to size (upper size ≤8 µm, mean size <4.5 ± 2 µm) and number (n ≤ 9 lipid droplets >5 µm). V concentrations were within an acceptable range, calculated for every timepoint as percent of the theoretical concentration spiked into the AiO PN. The median recovery was 98.2% (min–max, 90–112%). (4) At therapeutic doses, commercial V formulations were compatible and stable within specifications over one week in commonly used volumes of commercial AiO PN admixtures at 4–37 °C.

In(compatibility) of intravenous drugs in critical units: adult cohort

OBJECTIVES

To analyze potential (in)compatibilities of intravenous drugs based on the scheduling prepared by the nursing team.

METHODS

historic cohort (retrospective) with 110 adults in critical units. Intravenous medications were identified concomitantly, whose pairs were analyzed for (in) compatibility using the screening system Trissel's™ 2 Compatibility IV-Micromedex 2.0. Parametric and non-parametric statistic were used according to the nature of the variable.

RESULTS

565 pairs of drugs were identified. Of these, 44.9% were compatible; and 8.8%, potentially incompatible. Most potentially incompatible pairs involved substances with alkaline pH such as phenytoin (32%) and sodium bicarbonate (8%) and weak acids such as midazolam (12%) and dobutamine (6%), which could result in precipitate formation.

CONCLUSIONS

almost half of the mixtures simultaneously administrated was compatible, which indirectly reflects in the organized work between the nursing team and the clinical pharmaceutic in the discussions and decisions related to time scheduling.

Stability and Compatibility Aspects of Drugs: The Case of Selected Cephalosporins

Intravenous drug incompatibilities are a common cause of medical errors, contributing to ineffective therapy and even life-threatening events. The co-administration of drugs must always be supported by studies confirming compatibility and thus guarantee the therapy's safety. Particular attention should be paid to the possible incompatibilities or degradation of intravenous cephalosporins in different infusion regimens since the administration of drugs with inadequate quality may cause treatment failure. Therefore, an appropriate stability test should be performed. The study aimed to present various aspects of the stability and compatibility of five cephalosporins: cefepime (CFE), cefuroxime (CFU), ceftriaxone (CFX), ceftazidime (CFZ), and cefazoline (CFL). The degradation studies in parenteral infusion fluids and PN admixtures were conducted for CFE and CFU. The interactions between CFX or CFZ and PN admixtures, as well as the compatibility of CFL with five commercial parenteral nutrition (PN) admixtures, were investigated. The content of CFX and CFZ in PN admixture after 24 h was >90%. CFL administered simultaneously with PN admixture by the same infusion set using Y-site was compatible only with Nutriflex Lipid Special. CFE and CFU were stable in all tested infusion fluids for a minimum of 48 h and decomposed in PN admixtures during storage.

Strategies to prevent drug incompatibility during simultaneous multi-drug infusion in intensive care units: a literature review

PURPOSE

Drug protocols in intensive care units may require the concomitant administration of many drugs as patients' venous accesses are often limited. A major challenge for clinicians is to limit the risk of simultaneously infusing incompatible drugs. Incompatibilities can lead to the formation of particles and inactivation of drugs, whose consequences on the body have already been indicated. Our objective was to assess current strategies to counter the risk of incompatible infusions and control the resulting clinical consequences.

METHODS

This review was independently conducted by three investigators in respect of the PRISMA statement. Three online databases were consulted. Full-text articles, notes, or letters written in English or French, published or in press between the 1990s and the end of February 2020, with clinical study design, were eligible. Parameters of interest were mainly number and size of particles, and a number of observed/avoided incompatibilities.

RESULTS

All in all, 382 articles were screened, 17 meeting all the acceptance criteria. The strategies outlined and assessed were filtration, the use of multi-lumen devices, the purging of infusion lines, incompatibility tables and databases, and the use of standard operating procedures.

CONCLUSION

Although many strategies have been developed in recent years to address drug incompatibility risks, clinical data is still lacking. All studies with in vitro design were excluded although some current innovative strategies, like niosomes, should be considered and studied by means of clinical data in the future.

Optimising an Infusion Protocol Containing Cefepime to Limit Particulate Load to Newborns in a Neonatal Intensive Care Unit

Background: In neonatal intensive care units (NICUs), the simultaneous administration of drugs requires complex infusion methods. Such practices can increase the risk of drug incompatibilities resulting in the formation of a particulate load with possible clinical consequences. Methods: This paper evaluates strategies to reduce the particulate load of a protocol commonly used in NICUs with a potential medical incompatibility (vancomycin/cefepime combination). The protocol was reproduced in the laboratory and the infusion line directly connected to a dynamic particle counter to evaluate the particulate matter administered during infusion. A spectrophotometry UV assay of cefepime evaluated the impact of filters on the concentration of cefepime administered. Results: A significant difference was observed between the two infusion line configurations used in the NICU, with higher particulate load for cefepime infused via the emergency route. There was no change in particulate load in the absence of vancomycin. A filter on the emergency route significantly reduced this load without decreasing the cefepime concentration infused. Preparation of cefepime seemed to be a critical issue in the protocol as the solution initially contained a high level of particles. Conclusion: This study demonstrated the impact of a reconstitution method, drug dilution and choice of infusion line configuration on particulate load.

WoCoVA consensus on the clinical use of in-line filtration during intravenous infusions: Current evidence and recommendations for future research

The need for filtering intravenous infusions has long been recognized in the field of venous access, though hard scientific evidence about the actual indications for in-line filters has been scarce. In the last few years, several papers and a few clinical studies have raised again this issue, suggesting that the time has come for a proper definition of the type of filtration, of its potential benefit, and of its proper indications in clinical practice. The WoCoVA Foundation, whose goal is to increase the global awareness on the risk of intravenous access and on patients' safety, developed the project of a consensus on intravenous filtration. A panel of experts in different aspects of intravenous infusion was chosen to express the current state of knowledge about filtration and to indicate the direction of future research in this field. The present document reports the final conclusions of the panel.

Co-Administration of Drugs and Parenteral Nutrition: In Vitro Compatibility Studies of Loop Diuretics for Safer Clinical Practice

Parenteral nutrition (PN) admixtures are prone to interacting with drugs administered intravenously via a common catheter. This may cause a threat to a patient’s health and life. The literature that has been reported on the compatibility of loop diuretics with PN presents conflicting results. This work aimed to study the compatibility of furosemide and torsemide with PN used in clinical practice. Undiluted solutions of drugs were mixed with PN at various ratios determined by flow rates. In order to assess compatibility, visual control was followed by pH measurement, osmolality, mean emulsion droplet diameter (MDD), and zeta potential upon mixing and at 4 h of storage. No macroscopic changes that indicated lipid emulsion degradation were observed. After the addition of the drugs, the value of pH ranged from 6.37 ± 0.01 to 7.38 ± 0.01. The zeta potential was in reverse proportion to the drug concentration. The addition of the drugs did not affect the MDD. It may be suggested that the co-administration of furosemide or torsemide and PN caused no interaction. The absence of such signs of unwanted interactions allowed for the co-administration of the mentioned loop diuretics and PN at each of the studied ratios.

Incidence and Causes of Infusion Alarms in a Neonatal and Pediatric Intensive Care Unit: A Prospective Pilot Study

OBJECTIVES

To evaluate the incidence and causes of infusion alarms in a NICU/PICU setting.

METHODS

We conducted a 90-day prospective analysis of event logs downloaded daily from infusion pumps (syringe and volumetric pumps). The details about conditions surrounding alarm events were described daily by bedside nurses on a standardized form. The occlusion pressure alarm was set at 300 mm Hg on each device.

RESULTS

Forty-one pediatric patients including 12 neonates, mean weight 11.0 ± 11.3 kg (minimum-maximum, 0.48-50), were included for a total infusion time of 2164 hours. Eight hundred forty-three infusion alarms were documented (220 [26.1%] occlusion; 273 [32.4%] infusion completed; 324 [38.4%] door open/syringe disengagement; 26 [3.1%] air-in-line) resulting in an incidence of 4.7 infusion (1.2 occlusion) alarms per patient per day.Detailed conditions surrounding occlusion alarm events were documented in only 22.7% (50/220) of the cases. Of these, 36% (18/50) were related to closed or clamped lines, 4% (2/50) to syringe change, 16% (8/50) to drug injection, and 8% (4/50) to patient-related factors. The remaining 36% (18/50) occurred without any apparent external cause during ongoing infusion, among these drug incompatibilities were a potential cause for 12 events.

CONCLUSION

Alarms from infusion pumps were frequent in the NICU/PICU setting, a quarter of them resulting from line occlusion. Other than well-known triggers (mechanical and patient factors), drug incompatibilities were identified as a potential cause for occlusion alarms in this pilot study.

The Interactions between Ciprofloxacin and Parenteral Nutrition Admixtures

BACKGROUND

Co-infusion of parenteral nutrition (PN) and other drugs increases the risk of the interaction between drug and PN admixtures that can cause embolization of small blood vessels, resulting in potentially fatal consequences, including pulmonary embolism, or liver and retina vascular damage. The present study aimed to determine the compatibility between ciprofloxacin (CF) and eighteen compounded PN admixtures in order to assess the possibility of their co-administration via Y-sites.

METHODS

CF and PN admixtures were mixed at two volume ratios (1:1 and 2:1) and potential interactions were examined using visual inspection, and measurements of pH, osmolality particle size, and zeta potential. The analyses were conducted immediately after sample preparation and after four hours of storage.

RESULTS

The compatibility tests showed that the addition of the CF to the PN admixtures did not cause any color change or sign of destabilization in the fat emulsion. However, precipitation was observed in formulations containing higher CF concentrations and, in the case of lower CF concentrations, in formulations containing magnesium and calcium ions at a molar ratio of 2:1.

CONCLUSIONS

The administration of CF and PN admixtures via the Y-site should be avoided or performed only with PN admixtures for which compatibility has been confirmed and the CF concentration in samples is 1 mg/mL at a molar ratio of magnesium to calcium ions of 1:1.

Evaluation of Incompatible Coadministration of Continuous Intravenous Infusions in a Pediatric/Neonatal Intensive Care Unit

OBJECTIVES We aimed to evaluate and quantify incompatible coadministrations of continuous intravenous medication in the daily clinical practice of a PICU/NICU.

METHODS We conducted a retrospective, observational study in the setting of an 18-bed PICU/NICU. All concurrently administered continuous infusions, including blood products and parenteral nutrition, were analyzed for 2 months. Raw electronic data were retrieved and subjected to quality controls. Infusion combinations were classified as compatible, incompatible, no data, or variable according to the internal hospital charts, Trissel's database, and the Swiss summary of product characteristics. For situations with incompatible coadministrations, we assessed alternative distributions of infusions among the currently available lumen.

RESULTS Data for 100 patients were analyzed. Patients were exposed to a mean of 6.9 ± 3.6 individual continuous infusions administered through 3.8 ± 1.8 lumina. Among the 1447 coadministered continuous infusions, we detected 146 incompatible combinations (10%), resulting in 105 individually relevant incompatible situations. Furthermore, 185 combinations (13%) were not covered by internal compatibility charts, and for 207 combinations (15%) no data on compatibility were available. We found that 58% of the incompatible situations could have been avoided by a redistribution of the infusions among the available lumina.

CONCLUSIONS Most infusion combinations in the studied PICU/NICU were compatible and covered by the internal compatibility charts. However, we also identified concurrent administrations of incompatible infusions or for which compatibility data are not available. A significant reduction of coadministrations of incompatible infusions could be achieved through optimal use of available lumina.

Physicochemical Compatibility of Dexmedetomidine With Parenteral Nutrition

BACKGROUND

Dexmedetomidine is an α2-agonist used as a sedative agent in the intensive care setting. Simultaneous administration of dexmedetomidine and parenteral nutrition (PN) may be required. The aim of this study was to evaluate the physicochemical compatibility of dexmedetomidine Y-site administered with PN.

METHODS

Three PN and 3 dexmedetomidine solutions were compounded. The tested infusion rate for PN was 66 mL/h. For dexmedetomidine, we considered the initial and maximum infusion rates (0.7 and 1.4 µg/kg/h) detailed in the data sheet. Taking this into account and considering a weight range of 55-95 kg, we tested 2 dexmedetomidine infusion rates (10 and 36 mL/h). The samples obtained were examined visually against light. pH was analyzed with a pH meter. Mean fat droplet diameter was determined by dynamic light scattering. Quantification of dexmedetomidine concentration was carried out by ultraperformance liquid chromatography-high-resolution mass spectrometry. For each PN-dexmedetomidine admixture, tests were performed in triplicate.

RESULTS

No alterations were observed by visual inspection. Average pH was 6.25 ± 0.01. Droplet diameter remained below 500 nm (298 ± 10 nm for 10-mL/h rate and 303 ± 5 nm for 36-mL/h rate). Dexmedetomidine concentrations at t = 0 were 519 ± 31 ng/mL and 1391 ± 90 ng/mL for 10- and 36-mL/h infusion rates, respectively. At t = 24 hours, the concentrations obtained were 494 ± 22 and 1332 ± 102 ng/mL, which translates into ≥90% of the initial concentrations.

CONCLUSION

Dexmedetomidine is physicochemically compatible with PN during simulated Y-site administration at the tested infusion rates.

Physical compatibility of MCT/LCT propofol emulsions with crystalloids during simulated Y-site administration

Objective

In intensive care units numerous drugs have to be infused simultaneously, resulting inline incompatibility. Propofol is formulated as a lipid emulsion and it is well known that electrolytes can affect the stability of an emulsion system. Our goal was to evaluate and to compare the physical compatibility of three commercial propofol lipid emulsions of different manufacturers, mixing them with the most commonly used crystalloids in intensive care units.

Methods

Simulated Y-site administration was accomplished by mixing the 2% MCT/LCT propofol emulsions with the commonly used crystalloids in the intensive care unit in a 1:1 ratio in a polypropylene syringe. The aliquot samples were evaluated immediately and at 15, 30, 60 and 120 min after preparation by visual observation, pH and droplet size measurement.

Results

There was no emulsion breakdown or any visible change during the study period. Mixing the propofols with crystalloids, 10% magnesium sulphate or 10% potassium chloride there was no significant change in the droplet size compared with the original propofol emulsions. A slight alteration in droplet size was noticed in a few of the propofol samples, when magnesium, potassium or both were the secondary additives to the crystalloids, but this is not considered clinically relevant.

Conclusion

The physical properties of emulsions are determined by component, therefore the compatibility data in literature has to be evaluated prudently. All three commercially available MCT/LCT propofol emulsions are considered physically compatible with the tested crystalloids.

Drug incompatibilities in intravenous therapy: evaluation and proposition of preventive tools in intensive care and hematology units

PURPOSE

Physicochemical incompatibility (PCI) between drugs infused together is frequent, but under-recognized. PCI can lead to drug inactivity, catheter occlusion, embolism or inflammatory reactions. The aims of this work were to identify most frequent and relevant drug incompatibilities and to review and develop strategies for their prevention.

METHOD

This was an observational prospective survey conducted between January and March 2015 in an intensive care unit (ICU) and in September 2014 in a hematology sterile unit (HSU). Drugs administered to patients were recorded and their compatibility assessed based on published compatibility data.

RESULTS

Drug incompatibilities accounted for 12% (23/189) and 17% (116/686) of drug pairs infused in the ICU and the HSU, respectively. Pantoprazole was the most frequent drug implied in PCI. Regarding drug classes, anti-infective agents and gastrointestinal drugs were the most frequently implied. Among the incompatible pairs, 78% and 61% implicated a drug with extreme pH in the ICU and HSU, respectively. The tools proposed to reduce the frequency of PCI included: compatibility cross-tables, labeling of drugs with extreme pH and optimized administration schedules.

CONCLUSIONS

Given the frequency and the potential for severe consequences of PCI, pharmacists have a role to play in raising awareness of nurses and practitioners, and proposing adequate tools and solutions to reduce their incidence.

Analysis of particulate exposure during continuous drug infusion in critically ill adult patients: a preliminary proof-of-concept in vitro study

BACKGROUND

In critically ill patients, drug incompatibilities frequently occur because of the number of drugs to be administered through a limited number of infusion lines. These are among the main causes of particulate contamination. However, little data is available to quantify particle exposure during simultaneous IV-drug infusion. The objective of this study was to evaluate the particulate matter potentially administered to critically ill patients.

METHODS

The particulate matter (between 1 μm and 30 mm) of infused therapies used in ICUs for patients suffering from either septic shock or acute respiratory distress syndrome was measured in vitro over 6 h using a dynamic image analysis device, so that both overall particulate contamination and particle sizes could be determined. Data is presented according to the recommendations of the European Pharmacopoeia (≥ 10 and 25 μm).

RESULTS

For the six experimental procedures (continuous infusion of norepinephrine, midazolam, sufentanil, heparin, 5% glucose, binary parenteral nutrition and discontinuous administrations of omeprazole, piperacillin/tazobactam and fluconazole), the overall number of particles over the 6-h infusion period was 8256 [5013; 15,044]. The collected values for the number of particles ≥ 10 and 25 μm were 281 [118; 526] and 19 [7; 96] respectively. Our results showed that discontinuous administrations of drugs led to disturbances in particulate contamination.

CONCLUSIONS

This work indicates the amount of particulate matter potentially administered to critically ill adult patients. Particulate contamination appears lower than previous measurements performed during multidrug IV therapies in children.

Physicochemical Compatibility of Amiodarone with Parenteral Nutrition

BACKGROUND

Y-site administration of total parenteral nutrition (TPN) and drugs is frequently required in the intensive care setting. Amiodarone is commonly administered by continuous intravenous infusion and subject to be co-administered via a Y-site with TPN. The aim of this study is to determine the physicochemical stability of amiodarone Y-site administered with TPN.

METHODS

Two standard TPN and 2 amiodarone solutions were designed. The 2 TPN differed in the lipid source (Lipofundin MCT/LCT® 20% or SMOFlipid® 20%). The 2 amiodarone solutions were prepared at different concentrations (900 mg and 1200 mg in 250 mL of dextrose 5% in water). Each TPN and amiodarone solutions ran at a rate that simulated a 24-hour Y-site infusion to obtain different admixture samples. Each sample was then visually examined and further tested to determine the mean lipid droplet size distribution by dynamic light scattering and amiodarone concentrations by HPLC.

RESULTS

No alterations were detected by visual inspection. Average droplet size remained below 500 nm (252.5 ± 5.9 nm for Lipofundin MCT/LCT® TPN and 327.7 ± 14.4 nm for SMOFlipid® TPN). For the samples obtained after running 900 mg and 1200 mg amiodarone solutions with TPN, the concentrations observed at 24 hours were 0.4491 ± 0.0111 mg/mL and 0.5773 ± 0.0214 mg/mL, respectively. These results represent approximately 100% of the zero-time concentrations and are within ±15% of the predicted values. No degradation products were observed in the chromatograms.

CONCLUSION

Amiodarone is physicochemically compatible with standard TPN via a Y-site administration at the tested amiodarone concentrations.

Avoidance of Overt Precipitation and Patient Harm Following Errant Y-Site Administration of Calcium Chloride and Parenteral Nutrition Compounded With Sodium Glycerophosphate

Calcium phosphate precipitates present 1 of many challenges associated with parenteral nutrition (PN) compounding. Extensive research has led to the establishment of solubility curves to guide practitioners in the prescription and preparation of stable PN. Concurrent dosing of intravenous products via y-site administration with PN can alter the chemical balance of the solution and modify solubility. Medications containing calcium or phosphate should not be administered in the same line as PN, due to the high potential for precipitation. Herein a case is reported from a pediatric cardiac intensive care unit where a physician ordered the administration of calcium chloride. The bedside nurse added the calcium chloride intermittent infusion as a y-site administration with the patient's PN. The patient's PN had been compounded with sodium glycerophosphate, temporarily available in the United States during a sodium phosphate shortage. The patient did not experience any observable adverse effects from the y-site administration with PN. Following this event, the scenario was replicated to investigate any precipitation risk associated with the y-site administration. Additionally, a separate PN solution containing sodium phosphate rather than glycerophosphate was compounded and used in a laboratory setting to demonstrate the potential for harm had the patient's PN been compounded with an inorganic phosphate source. This replication of the error demonstrates the additional safety gained in relation to precipitation risk when PN solutions are compounded with sodium glycerophosphate in place of sodium phosphate.

Clinical implications of intravenous drug incompatibilities in critically ill patients

OBJECTIVE

The aim of this review is to analyse the clinical consequences of intravenous drug incompatibilities in critically ill patients, especially the incidence of organ dysfunctions and mortality.

METHODS

A review of literature was conducted according to the PRISMA statement in June 2017, using Medline, ISI Web of Science and Clinicaltrials.gov.

DATA EXTRACTION

Eligible studies were case reports and randomised controlled trials (RCTs) that assessed the effects of drug incompatibilities in critically ill patients on morbidity or mortality as primary or secondary outcomes, or adverse events. Two investigators independently reviewed the eligibility of the study from abstracts or manuscript data.

DATA SYNTHESIS

Twelve articles met the selection criteria. The six articles reporting RCTs concern only four RCTs. RCTs were single-centre studies comparing infusion with or without filter. One of them included adult patients. The others included paediatric and neonatal intensive care unit patients. Primary endpoints were SIRS, organ failure, overall complication rate, bacteraemia, sepsis, phlebitis and length of stay. The results are mixed with one RCT reporting a reduction in SIRS, organ failure and overall complication rate, two studies in disagreement over the occurrence of sepsis and one study reporting no impact on length of hospital stay. The six articles on case reports show different drug incompatibility situations. They report pulmonary toxicity.

CONCLUSION

Little data is available on this topic. Infused particles may induce organ failure, in particular pulmonary toxicity and SIRS. Further studies are needed to establish a link between the level of exposure to drug incompatibilities and clinical implication.

[IV drug perfusions: safety principles]

An intravenous perfusion is a procedure which comprises infection and medication risks. To manage these risks, caregivers must respect, in addition to the usual hygiene rules, a series of best practices, ensuring the proper use and management of the medical devices and administered drugs.

Calcium chloride in neonatal parenteral nutrition: A 15 year experience

OBJECTIVE

The objective of this study was to determine if outcomes at our neonatal intensive care units (NICUs) since we began using calcium chloride (CaCl2) as our preferred calcium additive in order to reduce aluminum (Al) exposure are within expected outcome ranges for NICUs in the U.S. where calcium gluconate in glass vials (CaGlu-Gl) has been the preferred additive.

STUDY DESIGN

A retrospective study of very low birth weight infants born between January 1, 2000 and December 31, 2014. Outcomes in two intensive care units (NICUs) using CaCl2 were compared to all U.S. NICUs in the Vermont Oxford Network. Primary outcomes were chronic lung disease (CLD), percent requiring supplemental oxygen at 28 days, and mortality excluding early deaths (MEED). The incidence of IV infiltrates of all admissions to the study NICUs in 2013-2014 was compared to the literature.

RESULTS

The incidence of CLD and those requiring oxygen at 28 days were 24.0% vs 28.6% and 46.2% vs 51.8% for the study NICUs compared to all U.S. NICUs, respectively (both p < 0.0001). The MEED was 8.7% vs 10.3% (p < 0.002). All major morbidities were lower at the study NICUs. The incidence of infiltrates was lower than that in the literature.

CONCLUSION

The use of CaCl2 was not associated with any detectable adverse effects. Calcium chloride appears to be a safe alternative to the use of CaGlu-Gl based upon studies of clinical outcomes.

Pharmaceutical and Clinical Aspects of Lipid Injectable Emulsions

The first clinically successful lipid injectable emulsion was marketed in 1961, consisting of soybean oil triglycerides in sterile water for injection. Since that time, numerous products have entered the market, with the main difference being changes in the oil composition with triglycerides of plant and marine oil origin. With this change, the fatty acid profiles are unique, coming from medium- and long-chain triglycerides. The fatty acids can be saturated or unsaturated, having different pharmaceutical and metabolic activities that affect the safety and efficacy of these unique pharmaceutical dosage forms.

Physicochemical stability and compatibility testing of levetiracetam in all-in-one parenteral nutrition admixtures in daily practice

BACKGROUND

Parenteral antiepileptic drugs are frequently used in critically ill patients for seizure control therapy or prevention. Many of these patients require additional parenteral nutrition (PN). Therefore, a parallel infusion of the frequently used antiepileptic drug levetiracetam (LEV) is interesting in terms of the restricted i.v. lines (e.g., neonates). The potential interactions of the complex PN admixture with the drug product and the appropriate admixing of a drug at effective dosages require physicochemical lab assessments to obtain specific and reliable pharmaceutical documentation for the intended admixing.

AIM

To assess the of compatibility and stability of LEV, a neutral and hydrophilic drug, in commercial all-in-one (AiO) PN admixtures using simple validated tests to provide necessary data in a timely manner and to allow convenient, documented and safe treatment with PN as the drug vehicle.

METHODS

Different concentrations of LEV were injected into two different AiO PN admixtures with no further additives. Stability and compatibility tests for the drug and the PN admixtures were performed over seven days at +4°C, +23±1°C and +37°C without light protection. Stability and sample characteristics were observed by visual inspection and the validated light microscope method. Moreover, the pH level of the admixture was checked, as were the concentrations of LEV over time in the PN admixtures, using an established LC-MS/MS method.

RESULTS

The stability controls of LEV at different temperatures were within absolute ±20% of the theoretical value in a concentration range of 98.91-117.84% of the initial value. No changes in pH occurred (5.55±0.04) and no microscopic out of specification data or visual changes were observed. The mean value of the largest lipid droplet in each visual field over seven days was 2.4±0.08μm, comparable to that of the drug-free AiO admixture. Samples stored at +37°C showed yellowish discolorations after 96h of storage.

CONCLUSION

LEV showed compatibility and stability over seven days in the selected PN admixtures, and the described methods represented a valuable and timely approach to determine the stability and compatibility of the highly hydrophilic, not dissociated LEV in AiO admixtures under conditions of use. Further studies with clinically relevant and representative examples of physicochemically different drug classes are needed.

Physical compatibility of total parenteral nutrition and drugs in Y-site administration to children from neonates to adolescents

OBJECTIVES

Infusion of precipitate or destabilized emulsion can be harmful. The purpose of this study was to obtain Y-site compatibility data on intravenous drugs and total parenteral nutrition (TPN) relevant for children.

METHODS

Two three-in-one TPN admixtures (Olimel N5E and Numeta G16E) used for children of different age groups were tested with ten drugs (ampicillin, ceftazidime, clindamycin, dexamethasone, fluconazole, fosphenytoin, furosemide, metronidazole, ondansetron and paracetamol). Drug : TPN ratios were estimated from a wide range of age and weight classes, and the most extreme mixing ratios (drug > TPN, TPN > drug) in addition to 1 + 1 were chosen. Assessment of potential precipitation was performed by subvisual particle counting, visual examinations and measurements of turbidity and pH. Emulsion stability was investigated by estimation of percentage of droplets above 5 μm (PFAT5), mean droplet diameter and pH measurements. Complimentary theoretical evaluations were performed.

KEY FINDINGS

Ampicillin, fosphenytoin and furosemide precipitated when mixed with TPN. The results for ceftazidime, clindamycin, dexamethasone, fluconazole, metronidazole, ondansetron and paracetamol suggest that they were compatible with either TPN in the tested concentrations. None of the drugs were found to destabilize the emulsions.

CONCLUSION

Three drugs showed clear signs of precipitation when mixed with TPN and these products should not be co-administered in the same infusion line.

Physicochemical compatibility and emulsion stability of propofol with commonly used analgesics and sedatives in an intensive care unit

Objectives

The purpose of this study was the determination of the physicochemical compatibility and emulsion stability of propofol with other sedatives and analgesics (clonidine hydrochloride, dexmedetomidine, 4-hydroxybutyric acid, (S)-ketamine, lormetazepam, midazolam hydrochloride, piritramide, remifentanil hydrochloride and sufentanil citrate) that are frequently administered together intravenously.

Methods

Drugs were mixed with propofol and stored without light protection at room temperature. Samples were taken at 10 points of time over 7 days. The physical stability and emulsion stability in particular were analysed by visual and microscopical inspection and by measurement of the pH value, zeta potential and globule size distribution. In addition, high-performance liquid chromatography and mass spectrometry were used to identify chemical incompatibilities.

Results

4-Hydroxybutyric acid, midazolam hydrochloride, piritramide and remifentanil hydrochloride are physically incompatible when mixed with propofol. The reason for this is the development of an increased fraction of oil droplets >5 µm leading to a higher risk of emboli. Moreover, propofol is chemically incompatible with remifentanil. The sorption of propofol to the rubber stopper of the syringe was another detectable incompatibility.

Conclusions

Propofol should not be administered with 4-hydroxybutyric acid, remifentanil hydrochloride, midazolam hydrochloride and piritramide through the same intravenous line. Based on the risk of sorption to the rubber material, propofol should be used with caution. A drug loss might occur that leads to an underdosing of the patient requiring a dose adjustment to avoid any adverse consequences. As a result of this study, the drug safety in intensive care units could be optimised.

Calcium and Phosphorous in Pediatric Parenteral Nutrition

Calcium (Ca) and phosphorus (P) are essential for various systemic functions, including bone mineralization. Adequate provision of Ca and P in pediatric parenteral nutrition (PN) solutions is necessary for skeletal growth and for the prevention of metabolic bone disease. The provision of adequate doses of Ca and P in pediatric PN solutions is complicated by the increased needs in preterm and term infants, solubility limitations, and venous access. Clinicians should be aware of the evidence that supports the optimal use of Ca and P in pediatric PN solutions, including studies that have evaluated dosing and solubility. The aim of this article is to review relevant literature and practices for the use of these two minerals in pediatric PN solutions. The vitamin D endocrine system, a critical component for Ca homeostasis and bone mineralization, is discussed, as well as clinical manifestations of metabolic bone disease and methods for its prevention, assessment, and treatment in pediatric patients receiving PN.

Reduced risk of pulmonary emboli in children treated with long-term parenteral nutrition

BACKGROUND & AIMS

Pulmonary embolism (PE) is a complication of parenteral nutrition (PN) with a prevalence of 35% in children. In 2003 new intravenous lipid emulsions (ILEs) with MCT, olive and/or fish oil in addition to soybean oil were introduced. The aim was to compare the incidence of PE before and after introduction.

METHODS

327 surveillance ventilation-perfusion (V/Q) scintigraphies from 68 children aged 0.3-15 years, treated with PN from 1993 to 2010, were retrospectively reviewed. Rate of PE/1000 central venous catheter (CVC) days, number of children with PE pre- and post-introduction of ILEs were compared. Multivariate analyses were performed for risk factors.

RESULTS

Twenty-two (32%) children (19/42 before 2003 and 3/26 after 2003, p = 0.007) had at least one episode of PE. Thirty seven (11%) episodes of PE were detected accounting for a mean of 0.2/1000 CVC days prior to 2003 and 0.05/1000 CVC days after 2003, p = 0.04. Regression analysis indicated that higher content of ILE/infusion (p = 0.045) and frequency of ILE of >3 nights/week were associated with more PE (p = 0.001). New ILEs were associated with lower risk (p = 0.003).

CONCLUSION

With a four-fold fall in incidence with new ILE, PE remains a complication. We recommend 12-18 monthly surveillance with lung perfusion scan and anticoagulants if PE is diagnosed.

Development and evaluation of a test program for Y-site compatibility testing of total parenteral nutrition and intravenous drugs

Background

There is no standardized procedure or consensus to which tests should be performed to judge compatibility/incompatibility of intravenous drugs. The purpose of this study was to establish and evaluate a test program of methods suitable for detection of physical incompatibility in Y-site administration of total parenteral nutrition (TPN) and drugs.

Methods

Eight frequently used methods (dynamic light scattering, laser diffraction, light obscuration, turbidimetry, zeta potential, light microscopy, pH-measurements and visual examination using Tyndall beams), were scrutinized to elucidate strengths and weaknesses for compatibility testing. The responses of the methods were tested with samples containing precipitation of calcium phosphate and with heat destabilized TPN emulsions. A selection of drugs (acyclovir, ampicillin, ondansetron and paracetamol) was mixed with 3-in-1 TPN admixtures (Olimel® N5E, Kabiven® and SmofKabiven®) to assess compatibility (i.e. potential precipitates and emulsion stability). The obtained compatibility data was interpreted according to theory and compared to existing compatibility literature to further check the validity of the methods.

Results

Light obscuration together with turbidimetry, visual inspection and pH-measurements were able to capture signs of precipitations. For the analysis of emulsion stability, light obscuration and estimation of percent droplets above 5 μm (PFAT5) seemed to be the most sensitive method; however laser diffraction and monitoring changes in pH might be a useful support. Samples should always be compared to unmixed controls to reveal changes induced by the mixing. General acceptance criteria are difficult to define, although some limits are suggested based on current experience. The experimental compatibility data was supported by scattered reports in literature, further confirming the suitability of the test program. However, conflicting data are common, which complicates the comparison to existing literature.

Conclusions

Testing of these complex blends should be based on a combination of several methods and accompanied by theoretical considerations.

Particulate Matter in Injectable Drugs: Evaluation of Risks to Patients

One of the fundamental principles guiding the pharmaceutical quality of parenteral products is to prevent injecting contaminants from microbiological, chemical or physical sources. It is just as difficult to ensure the absence of chemical and particulate contaminants in injectable products as it is to weigh up the microbiological risk. The problem of particulate matter is mainly related to the preparing and administrating of injectable drugs rather than through the contamination of marketed products. Particulate contamination also arises

Dextrose-mediated aggregation of therapeutic monoclonal antibodies in human plasma: Implication of isoelectric precipitation of complement proteins

Many therapeutic monoclonal antibodies (mAbs) are clinically administered through intravenous infusion after mixing with a diluent, e.g., saline, 5% dextrose. Such a clinical setting increases the likelihood of interactions among mAb molecules, diluent, and plasma components, which may adversely affect product safety and efficacy. Avastin® (bevacizumab) and Herceptin® (trastuzumab), but not Remicade® (infliximab), were shown to undergo rapid aggregation upon dilution into 5% dextrose when mixed with human plasma in vitro; however, the biochemical pathways leading to the aggregation were not clearly defined. Here, we show that dextrose-mediated aggregation of Avastin or Herceptin in plasma involves isoelectric precipitation of complement proteins. Using mass spectrometry, we found that dextrose-induced insoluble aggregates were composed of mAb itself and multiple abundant plasma proteins, namely complement proteins C3, C4, factor H, fibronectin, and apolipoprotein. These plasma proteins, which are characterized by an isoelectronic point of 5.5–6.7, lost solubility at the resulting pH in the mixture with formulated Avastin (pH 6.2) and Herceptin (pH 6.0). Notably, switching formulation buffers for Avastin (pH 6.2) and Remicade (pH 7.2) reversed their aggregation profiles. Avastin formed little, if any, insoluble aggregates in dextrose-plasma upon raising the buffer pH to 7.2 or above. Furthermore, dextrose induced pH-dependent precipitation of plasma proteins, with massive insoluble aggregates being detected at pH 6.5–6.8. These data show that isoelectric precipitation of complement proteins is a prerequisite of dextrose-induced aggregation of mAb in human plasma. This finding highlights the importance of assessing the compatibility of a therapeutic mAb with diluent and human plasma during product development.

Fatal foreign-body granulomatous pulmonary embolization due to microcrystalline cellulose in a patient receiving total parenteral nutrition: all crystals are not what they seem

Pulmonary foreign-body granulomatous embolization has been described secondary to crystal precipitation in total parenteral nutrition (TPN) as well as when pharmaceutical tablets are crushed and injected intravenously. Extensive granulomatous embolization may cause pulmonary hypertension and death due to acute cor pulmonale. We report the case of a 34-year old woman who had been receiving TPN post-operatively secondary to complications of a paraesophageal hernia repair. During and following receiving TPN, she experienced episodes of hypoxia, tachycardia, fever, and hypotension. Computed tomography scans of the thorax showed centrilobular nodules, tree-in-bud and ground-glass opacities, as well as findings of pulmonary hypertension. Following an episode of hypoxia she was found unresponsive and died despite resuscitative efforts. Microscopic examination of the lungs following post-mortem examination revealed occlusive granulomatous inflammation of the pulmonary arterial vasculature by crystalline material. The morphologic and histochemical patterns of the crystals were suggestive of microcrystalline cellulose, a finding that was confirmed by energy dispersive X-spectroscopy and infrared spectroscopy. Ancillary tests did not support that the crystalline material was the result of TPN precipitation. Foreign-body granulomatous embolization leading to acute core pulmonale may occur as a complication of both intravenous injection of oral medications as well as of TPN crystallization. The source of crystalline material may be difficult to discern based solely on morphological assessment or by histochemical staining. Ancillary studies such as energy dispersive X-spectroscopy or infrared spectroscopy should be performed to definitively discern the two entities.

Respiratory Distress and Sudden Death Associated with Receipt of a Peripheral Parenteral Nutrition Admixture

Objective:

To detect respiratory adverse reac¬tions potentially related to receipt of peripheral parenteral nutrition (PPN) in hospitalized patients and to determine risk factors for their occurrence.

Design:

Retrospective cohort study.

Setting:

Federal tertiary-care hospital.

Patients:

Medical and pharmacy records of all patients who received PPN from October 1992 to February 1994 were abstracted for demographics, diagnoses, medications received, indications for and formulation of PPN, and severity of illness as measured by Acute Physiology and Chronic Health Evaluation II scores.

Results:

A case-patient was defined as any patient who, while receiving PPN, had unexplained chest pain, dyspnea, cardiopulmonary arrest, or new interstitial infiltrates on chest radiograph. Patients who received PPN in which FreAmine was the amino acid source were more likely than those who received PPN made with Travasol to meet the case definition (5/11 vs 0/39; relative risk, >18; 95% confidence interval, 3.3->136; P<.001).

Conclusions:

A change in the amino acid source of a PPN admixture was associated with respiratory adverse events that ranged from interstitial infiltrates to sudden death. These events apparently resulted from the infusion of a calcium phosphate precipitate in an opaque admixture. Each new PPN admixture should be tested for stability before clinical use and infused into patients through an appropriate filter.

Phosphorus and calcium: a review for the adult nutrition support clinician

Phosphorus (P) and calcium (Ca) serve vital roles in the human body and are essential components of nutrition support therapy. Regulation of P and regulation of Ca in the body are closely interrelated, and P and Ca homeostasis can be affected by several factors, including disease states, clinical condition, severity of illness, and medications. Nutrition support clinicians must understand these factors to prevent and treat P and Ca disorders in patients receiving nutrition support therapy. This review provides an overview of P and Ca for the adult nutrition support clinician, with some emphasis on the hospitalized inpatient.