Peripheral infusion as the route of choice for intravenous nutrition: a prospective two year study

Supplemental Parenteral Nutrition: Review of the Literature and Current Nutrition Guidelines

Parenteral nutrition has significantly and positively affected the clinical care of patients for >50 years. The 2016 Society of Critical Care Medicine/American Society for Parenteral and Enteral Nutrition guidelines for the provision of nutrition support to adult patients emphasize the role of this therapy in attenuating the stress response and impacting the immune response, among other benefits. Malnutrition in hospitalized patients remains a major problem; it is underdiagnosed and often undertreated. Malnourished patients are more likely to suffer from infections, pneumonia, and pressure ulcers, among other serious concerns. Enteral nutrition is considered first-line therapy in many of these patients; however, data suggest that many patients receive far less than prescribed amounts for a variety of reasons. Supplemental parenteral nutrition (SPN), used to augment nutrition support of appropriate adult patients and better meet nutrition goals, is not often used in the United States. The purposes of this review are to highlight selected studies in the literature that support and question the use and value of SPN in adult patients; propose consideration of 2 definitions for SPN, "early" and "traditional"; and encourage clinicians to consider SPN for appropriate patients.

When Is Parenteral Nutrition Appropriate?

Parenteral nutrition (PN) represents one of the most notable achievements of modern medicine, serving as a therapeutic modality for all age groups across the healthcare continuum. PN offers a life-sustaining option when intestinal failure prevents adequate oral or enteral nutrition. However, providing nutrients by vein is an expensive form of nutrition support, and serious adverse events can occur. In an effort to provide clinical guidance regarding PN therapy, the Board of Directors of the American Society for Parenteral and Enteral Nutrition (ASPEN) convened a task force to develop consensus recommendations regarding appropriate PN use. The recommendations contained in this document aim to delineate appropriate PN use and promote clinical benefits while minimizing the risks associated with the therapy. These consensus recommendations build on previous ASPEN clinical guidelines and consensus recommendations for PN safety. They are intended to guide evidence-based decisions regarding appropriate PN use for organizations and individual professionals, including physicians, nurses, dietitians, pharmacists, and other clinicians involved in providing PN. They not only support decisions related to initiating and managing PN but also serve as a guide for developing quality monitoring tools for PN and for identifying areas for further research. Finally, the recommendations contained within the document are also designed to inform decisions made by additional stakeholders, such as policy makers and third-party payers, by providing current perspectives regarding the use of PN in a variety of healthcare settings.

Access technique and its problems in parenteral nutrition - Guidelines on Parenteral Nutrition, Chapter 9

Catheter type, access technique, and the catheter position should be selected considering to the anticipated duration of PN aiming at the lowest complication risks (infectious and non-infectious). Long-term (>7-10 days) parenteral nutrition (PN) requires central venous access whereas for PN <3 weeks percutaneously inserted catheters and for PN >3 weeks subcutaneous tunnelled catheters or port systems are appropriate. CVC (central venous catheter) should be flushed with isotonic NaCl solution before and after PN application and during CVC occlusions. Strict indications are required for central venous access placement and the catheter should be removed as soon as possible if not required any more. Blood samples should not to be taken from the CVC. If catheter infection is suspected, peripheral blood-culture samples and culture samples from each catheter lumen should be taken simultaneously. Removal of the CVC should be carried out immediately if there are pronounced signs of local infection at the insertion site and/or clinical suspicion of catheter-induced sepsis. In case PN is indicated for a short period (max. 7-10 days), a peripheral venous access can be used if no hyperosmolar solutions (>800 mosm/L) or solutions with a high titration acidity or alkalinity are used. A peripheral venous catheter (PVC) can remain in situ for as long as it is clinically required unless there are signs of inflammation at the insertion site.

ESPEN Guidelines on Parenteral Nutrition: central venous catheters (access, care, diagnosis and therapy of complications)

When planning parenteral nutrition (PN), the proper choice, insertion, and nursing of the venous access are of paramount importance. In hospitalized patients, PN can be delivered through short-term, non-tunneled central venous catheters, through peripherally inserted central catheters (PICC), or - for limited period of time and with limitation in the osmolarity and composition of the solution - through peripheral venous access devices (short cannulas and midline catheters). Home PN usually requires PICCs or - if planned for an extended or unlimited time - long-term venous access devices (tunneled catheters and totally implantable ports). The most appropriate site for central venous access will take into account many factors, including the patient's conditions and the relative risk of infective and non-infective complications associated with each site. Ultrasound-guided venepuncture is strongly recommended for access to all central veins. For parenteral nutrition, the ideal position of the catheter tip is between the lower third of the superior cava vein and the upper third of the right atrium; this should preferably be checked during the procedure. Catheter-related bloodstream infection is an important and still too common complication of parenteral nutrition. The risk of infection can be reduced by adopting cost-effective, evidence-based interventions such as proper education and specific training of the staff, an adequate hand washing policy, proper choices of the type of device and the site of insertion, use of maximal barrier protection during insertion, use of chlorhexidine as antiseptic prior to insertion and for disinfecting the exit site thereafter, appropriate policies for the dressing of the exit site, routine changes of administration sets, and removal of central lines as soon as they are no longer necessary. Most non-infective complications of central venous access devices can also be prevented by appropriate, standardized protocols for line insertion and maintenance. These too depend on appropriate choice of device, skilled implantation and correct positioning of the catheter, adequate stabilization of the device (preferably avoiding stitches), and the use of infusion pumps, as well as adequate policies for flushing and locking lines which are not in use.

Peripheral parenteral nutrition

BACKGROUND

Peripheral parenteral nutrition (PPN) currently accounts for almost 20 per cent of all parenteral nutrition administered in the UK. In the absence of consensus guidelines there is wide variation in practice. Heterogeneity of clinical trials has made direct comparisons difficult and meta-analysis impossible.

METHODS

Medline, Embase and Cochrane databases were searched for all clinical trials relating to the use of PPN in adults. Relevant papers from the reference lists of these articles and from the authors' personal collections were also reviewed.

RESULTS AND CONCLUSIONS

Effective PPN is possible in about 50 per cent of inpatients requiring parenteral nutrition. Evidence relating to optimal feed composition, choice of cannula, infusion technique and pharmacological manipulation is discussed, along with practical recommendations for the administration of PPN.

Prospective survey of parenteral nutrition in Switzerland: a three-year nation-wide survey

BACKGROUND AND AIMS

The goals of this national survey were to determine the current PN practices and admixture formulations used in Switzerland.

METHODS

During three years, an annual questionnaire was sent to all heads of Swiss hospital pharmacies.

RESULTS

92% of Swiss hospitals with a full-time pharmacist participated. Different PN systems were commonly used for adult patients: 2 commercial formulas in 2 or 3 compartments bags, 2 commercial formulas with/without lipid, 3 formulas compounded by the hospital pharmacy. For hospitalized adults, 83% of PN bags were administered as commercial multicompartment bags. The compounding of individualized PN admixtures takes place primarily in pharmacies of medium to large size hospitals. For pediatric PN, hospital compounding is routine because of individualized PN compositions and absence of commercially available standardized admixtures. Long-term home-PN was mostly delivered by hospital pharmacies (57%) or by private nutrition support home delivery services (37%). Most PN formula compositions complied with European guidelines and represented 2.6+/-2.0% of the hospital drug budget. Multi-disciplinary nutritional support teams were present in 52% of hospitals.

CONCLUSION

In Switzerland, most PN for hospitalized adults were administered as commercial multi-compartment bags. The compounding of individualized PN admixtures were still important for pediatric patients and long-term home-PN.

Experimental infusion phlebitis: tolerance osmolality of peripheral venous endothelial cells

This study aimed to determine the osmolality that peripheral venous endothelial cells can tolerate and to clarify the relationship between tolerance osmolality and duration of infusion. Nutrient solutions of 539-917 mOsm/kg, prepared to have no acidic effect, were infused into rabbit ear veins, and the veins were examined histopathologically. In each experiment of 8-, 12-, or 24-h infusion, the higher osmolality solutions caused some phlebitic changes, such as loss of venous endothelial cells, inflammatory cell infiltration, and edema; however, the lowest osmolality solution caused few changes. Infusion of 120 mL/kg of 814 mOsm/kg solution caused phlebitis at 5 or 10 mL.kg-1.h-1, however, the same volume of the same solution scarcely caused phlebitis at 15 mL.kg-1.h-1 because of the shortened infusion duration. These results suggest that the tolerance osmolality of peripheral venous endothelial cells with poor blood flow is about 820 mOsm/kg for 8 h, 690 mOsm/kg for 12 h, and 550 mOsm/kg for 24 h, and that the tolerance osmolality falls as the duration of infusion increases. In conclusion, hypertonic solutions should be infused at as high a rate as is clinically acceptable and compatible with nutrient bioavailability because increasing the infusion rate reduces the duration of infusion and phlebitis.

The various types of parenteral fluids and their indications

Assessment of hydration and perfusion is essential in patient evaluation. The acid-base and electrolyte disturbances that accompany many illnesses should also be considered. The duration of illness and body systems involved are also of major importance in patient evaluation. Fluid therapy is an important and potentially life-saving treatment of many and varied problems. The clinician must be able to assess the patient and determine whether the intravascular or extravascular compartments, or both, are deficient. Of primary concern is the status of the intravascular volume, then restoration of total body water and electrolytes. Fluid therapy is divided into three phases; the emergency phase, the rehydration phase, and the maintenance phase; not all patients require the three-phase therapy. The clinician must also be able to select (1) the appropriate solution to treat the volume deficit and correct the acid-base and electrolyte abnormalities and (2) the rate of administration to optimize outcome. Therefore, knowledge of electrolyte composition in plasma and of the various types of commercially available fluids is essential in order to select the appropriate therapy for the individual animal. In addition to the therapeutic aspects of fluid therapy, a knowledge of the side effects and complications of inappropriate fluid selection and rate of delivery is also important. With the individual requirements of each patient seen in a practice, the prescription approach to parenteral fluid therapy will optimize patient response to this extremely important aspect of overall patient management as well as make the practice of fluid therapy intellectually stimulating. This article has introduced the clinician to the parenteral fluids available and their indications in veterinary patients; it also contains a discussion of how to utilize preferred solutions for treatment of specific diseased states. Although there are definite "right" and "wrong" fluids to select for specific problems, there also remains individual preference in fluid choice, which is based on appropriate laboratory data and the practitioner's clinical judgment of the status of the individual patient vis-à-vis the spectrum of its disease. Recommendations for selection of different fluid types to treat similar conditions are usually based on these variables.

Basic principles for compounding all-in-one parenteral nutrition admixtures

Parenteral nutrition admixtures are complex pharmaceutical entities. The more closely they are examined, the more physico-chemical interactions emerge that could potentially affect stability. The move towards large scale hospital or commercial preparation, with a requirement for extended shelf life, and the increasing use of admixtures as vehicles for drugs and pharmaconutrients have created new formulation challenges for pharmaceutical scientists.

Dilution is effective in reducing infusion phlebitis in peripheral parenteral nutrition: an experimental study in rabbits

To clarify conflicting clinical results that had been reported as to whether dilution is effective or not in reducing infusion phlebitis, this study was undertaken. We undertook two experiments with the different infusion conditions in rabbits to confirm the generality and the reproducibility of the results. To test the effect of dilution, 120 mL/kg of solution A (784 mOsm/kg) was infused into rabbit ear veins at 10 mL.kg-1.h-1 for 12 h, and 144 mL/kg of 1.2-fold-diluted solution A (648 mOsm/kg) was infused at 12 mL.kg-1.h-1 for 12 h. Similarly, 120 mL/kg of solution B (718 mOsm/kg) was infused at 5 mL.kg-1.h-1 for 24 h, and 168 mL/kg of 1.4-fold-diluted solution B (514 mOsm/kg) was infused at 7 mL.kg-1.h-1 for 24 h. The infused veins were sampled 24 h after the end of the infusion and examined histopathologically. After the 12-h infusion, phlebitic changes were observed in six of eight rabbits given solution A but in only one of eight rabbits given diluted solution A, although the same quantities of the same nutrients were infused. Also, after the 24-h infusion, phlebitic changes were observed in six of eight rabbits given solution B but in no animals given diluted solution B. The same result that dilution reduced or eliminated phlebitic changes was confirmed in the different conditions. These results suggest that osmolality of the infusion solution is an important factor in the development of phlebitis regardless of infusion volume or infusion rate and that dilution is effective in reducing the phlebitic potential of infusion solutions.