Effect of pH in glucose infusions on development of thrombophlebitis

Development of Toxic Degradation Products during Heat Sterilization of Glucose-Containing Fluids for Peritoneal Dialysis: Influence of Time and Temperature

Objective

Fluids for peritoneal dialysis (PD) cause cytotoxic reactions in many different in vitro systems. The low pH, the high osmolality of the fluids, and the glucose degradation products formed during heat sterilization have been considered responsible. In the present study, we investigate the influence of temperature and time during heat sterilization of PD fluids and glucose solutions on glucose degradation and cytotoxicity of the solutions.

Design

Ampoules containing PD-fluid or glucose solution were heated in an oil bath to predetermined F o values (combinations of time and temperature giving equal energy/bacteriallethality). Cytotoxicity of the solutions was measured as groWth inhibition of cultured L-929 fibroblasts. Glucose degradation was measured as UV absorbance at 228 and 284 nm.

Results

The same general pattern was seen in both PD fluid and glucose solution. Cytotoxicity decreased from 90% to 15% when the sterilization temperature was increased from 115° to 140°C and concomitantly the length of time shortened in order to maintain equal bacteriallethality. Under the same conditions, degradation products, measured as UV absorbance at 284 nm, decreased from 0.2 to 0.02.

Conclusion

To minimizethe development of cytotoxic breakdown products, high temperatures over short periods of time should be used to heat-sterilize PD fluids. Even as small an increase as 5°C at around 120°C will improve the quality of the solutions.

Degradation in Peritoneal Dialysis Fluids May be Avoided by Using Low pH and High Glucose Concentration

Objective

When glucose is present in a medical fluid, the heat applied during sterilization leads to degradation. The glucose degradation products (GDPs) give rise to bioincompatible reactions in peritoneal dialysis patients. The extent of the degradation depends on a number of factors, such as heating time, temperature, pH, glucose concentration, and catalyzing substances. In the present work, we investigated the influence of pH and concentration in order to determine how to decrease the amounts of GDPs produced.

Design

Glucose solutions (1% - 60% glucose; pH 1 - 8) were heat sterilized at 121°C. Ultraviolet (UV) absorption, aldehydes, pH, and inhibition of cell growth (ICG) were used as measures of degradation.

Results

Glucose degradation was minimum at an initial pH (prior to sterilization) of around 3.5 and at a high concentration of glucose. There was considerable development of acid degradation products during the sterilization process when the initial pH was high. Two different patterns of development of UV-absorbing degradation products were seen: one below pH 3.5, dominated by the formation of 5-hydroxy-methyl-2-furaldehyde (5-HMF); and one above, dominated by degradation products absorbing at 228 nm. 3-Deoxyglucosone (3-DG) concentration and the portion of 228 nm UV absorbance not caused by 5-HMF were found to relate to the in vitro bioincompatibility measured as ICG; there was no relation between 5-HMF or absorbance at 284 nm and bioincompatibility.

Conclusion

In order to minimize the development of bioincompatible GDPs in peritoneal dialysis fluids during heat sterilization, pH should be kept around 3.2 and the concentration of glucose should be high. 5-HMF and 284 nm UV absorbance are not reliable as quality measures. 3-DG and the portion of UV absorbance at 228 nm caused by degradation products other than 5-HMF seem to be reliable indicators of bioincompatibility.

Safe administration of vancomycin through a novel midline catheter: a randomized, prospective clinical trial

BACKGROUND

According to the 2011 Infusion Nursing Standards of Practice, the low pH of intravenous vancomycin requires that it be administered through a central line. However, a careful review of the literature and a retrospective analysis of the experience at New York Hospital Queens (NYHQ) did not support the position of the Standards.

PURPOSE

A prospective, controlled, randomized clinical trial was conducted to determine if intravenous vancomycin could be safely administered through a novel midline catheter (POWERWAND®, Access Scientific, San Diego, CA).

METHODS

Patients scheduled to receive short-term (<6 days) intravenous vancomycin were randomly assigned to receive treatment through either a peripherally inserted central catheter (PICC) or the midline study device. Complications and the costs of insertion were recorded.

RESULTS

The two groups did not differ significantly with respect to total complications (17.9% with PICCs vs. 19.9% with the midline), phlebitis (0% vs. 0%) or thrombosis (0% vs. 0%). One suspected catheter-associated bloodstream infection did occur in the PICC group. Insertion costs were $90.00 less per insertion in the midline group.

CONCLUSIONS

Short-term intravenous vancomycin can be safely and cost-efficiently administered in the deep vessels of the upper arm using the midline study device.

Risk Factors for Upper Extremity Venous Thrombosis Associated with Peripherally Inserted Central Venous Catheters

Purpose

To identify clinically important risk factors associated with upper extremity venous thrombosis following peripherally inserted central venous catheters (PICC).

Methods

A retrospective case control study of 400 consecutive patients with and without upper extremity venous thrombosis post-PICC insertion was performed. Patient data included demographics, body mass index (BMI), ethnicity, site of insertion, size and lumen of catheter, internal length, infusate, and co-morbidities, such as diabetes mellitus, congestive heart failure, and renal failure. Additional risk factors analyzed were active cancer, any history of cancer, recent trauma, smoking, a history of prior deep vein thrombosis, and recent surgery, defined as surgery within three months prior to PICC insertion.

Results

The prevalence of trauma, renal failure, and infusion with antibiotics and total parenteral nutrition (TPN) was higher among patients exhibiting upper extremity venous thrombosis (UEVT), when compared to controls. Patients developing UEVT were also more likely to have PICC line placement in a basilic vein and less likely to have brachial vein placement (P<.001). Left-sided PICC line sites also posed a greater risk (P=.026). The rate of standard DVT prophylaxis with low molecular weight heparin and unfractionated heparin and the use of warfarin was similar in both groups. Average length of hospital stay was almost double among patients developing UEVT, 19.5 days, when compared to patients undergoing PICC line insertion without thrombosis, 10.8 days (t=6.98, P<.001).

Conclusions

In multivariate analysis, trauma, renal failure, left-sided catheters, basilic placement, TPN, and infusion with antibiotics, specifically vancomycin, were significant risk factors for UEVT associated with PICC insertion. Prophylaxis with low molecular weight heparin, unfractionated heparin or use of warfarin did not prevent the development of venous thrombosis in patients with PICCs. Length of hospital stay and cost are markedly increased in patients who develop PICC-associated upper extremity venous thrombosis.

Intra-ophthalmic artery chemotherapy triggers vascular toxicity through endothelial cell inflammation and leukostasis

Purpose. Super-selective intra-ophthalmic artery chemotherapy (SSIOAC) is an eye-targeted drug-delivery strategy to treat retinoblastoma, the most prevalent primary ocular malignancy in children. Unfortunately, recent clinical reports associate adverse vascular toxicities with SSIOAC using melphalan, the most commonly used chemotherapeutic. Methods. To explore reasons for the unexpected vascular toxicities, we examined the effects of melphalan, as well as carboplatin (another chemotherapeutic used with retinoblastoma), in vitro using primary human retinal endothelial cells, and in vivo using a non-human primate model, which allowed us to monitor the retina in real time during SSIOAC. Results. Both melphalan and carboplatin triggered human retinal endothelial cell migration, proliferation, apoptosis, and increased expression of adhesion proteins intracellullar adhesion molecule-1 [ICAM-1] and soluble chemotactic factors (IL-8). Melphalan increased monocytic adhesion to human retinal endothelial cells. Consistent with these in vitro findings, histopathology showed vessel wall endothelial cell changes, leukostasis, and vessel occlusion. Conclusions. These results reflect a direct interaction of chemotherapeutic drugs with both the vascular endothelium and monocytes. The vascular toxicity may be related to the pH, the pulsatile delivery, or the chemotherapeutic drugs used. Our long-term goal is to determine if changes in the drug of choice and/or delivery procedures will decrease vascular toxicity and lead to better eye-targeted treatment strategies.

Real-time ophthalmoscopic findings of superselective intraophthalmic artery chemotherapy in a nonhuman primate model

OBJECTIVE

To report real-time ophthalmoscopic findings during superselective intraophthalmic artery chemotherapy (SSIOAC) in a nonhuman primate model.

METHODS

Six adult male Rhesus macaques (Macacca mulatta) were randomly assigned to 1 of 2 treatment cohorts: melphalan (5 mg/30 mL) or carboplatin (30 mg/30 mL). Each animal underwent 3 separate SSIOAC procedures at 3-week intervals. Digital retinal images were obtained during each infusion. Intravenous fluorescein angiography was performed immediately after each procedure.

RESULTS

All SSIOAC procedures were successfully completed. Toxicities were equally distributed between drug cohorts. Systemic toxicities included mild bone marrow suppression in all animals and anorexia in 1. One animal had greater than 50% narrowing of the treated ophthalmic artery after its second infusion. All 18 procedures (100%) resulted in pulsatile optic nerve and choroid blanching, retinal artery narrowing, and retinal edema. Of the 18 procedures, retinal artery sheathing was found during 17 (94%), and retinal artery precipitates were seen in 10 (56%); choroidal hypoperfusion was seen by fluorescein angiogram in 18 (100%).

CONCLUSION

Real-time ophthalmic investigations are useful and, in our nonhuman primate model, indicate prevalent, acute ocular vascular toxicities during SSIOAC.

CLINICAL RELEVANCE

Real-time retinal imaging is feasible in a nonhuman primate model of SSIOAC. Application to SSIOAC in children may shed insight into reported vascular toxicities.

Ageing of intravenous glucose solutions

The pH and acid content of 63 glucose-based solutions was measured up to eight years after their expiry. The pH ranged from 2.27 to 4.33. Newly manufactured solutions with 5 per cent or less of glucose which were packaged in plastic bags contained in the order of 0.01 mEq/L of acid per gram of glucose. Solutions with higher glucose concentrations had lower pH and greater acid. As solutions in bags became older, pH decreased and acid increased. In contrast, 25 per cent and 50 per cent glucose solutions in glass containers were much less acid and showed only slight changes with age in pH or acid. The greater rate of acid increase in glucose solutions in plastic bags may be due to the bags being permeable to oxygen and thus allowing slow oxidation of the glucose.

Methods of preventing vinorelbine-induced phlebitis: an experimental study in rabbits

PURPOSE

In order to identify methods for preventing phlebitis caused by intravenous administration of vinorelbine (VNR), we established a procedure for estimating the severity of phlebitis in an animal model.

METHODS

Four different factors (administration rate, dilution, flushing, and infusion of fat emulsion) were evaluated for alleviation of phlebitis caused by VNR infusion. VNR was diluted with normal saline to prepare test solutions with concentrations of 0.6 mg/mL or 0.3 mg/mL for infusion into the auricular veins of rabbits. Two days after VNR infusion, the veins were subjected to histopathological examination.

RESULTS

VNR did not cause obvious loss of venous endothelial cells, the most sensitive and common feature of phlebitis, but VNR infusion led to inflammatory cell infiltration, edema, and epidermal degeneration. Tissue damage was significantly decreased by shortening the administration time and by diluting the VNR solution for infusion from 0.6 mg/mL to 0.3 mg/mL. However, there was no effect of flushing with normal saline after VNR infusion, while treatment with fat emulsion before and after VNR infusion only had a minimal effect.

CONCLUSION

Rapid infusion and dilution are effective methods of reducing phlebitis caused by the infusion of VNR, but the efficacy of flushing with normal saline or infusion of fat emulsion was not confirmed.

The local vascular tolerance to an intravenous infusion of a concentrated glutamine solution in ICU patients

BACKGROUND AND AIMS

The beneficial effects of glutamine is well-documented in ICU patients. However, the documentation and control of enteral administration of glutamine is still insufficient. As an adjunct to enteral nutrition, a concentrated dipeptide solution may be given in a central venous line, but administration via a peripheral vein would be preferable. Therefore, we systematically evaluated local vascular tolerance following a concentrated dipeptide infusion in ICU-patients.

METHODS

ICU-patients (n=20) were randomized to receive a 20% alanyl-glutamine infusion of 0.5 g/kg or placebo during 4 h in a peripheral vein on 3 consecutive days. Local tolerance was evaluated clinically, by Maddox score, and ultrasonically before the infusion and on days 1, 4 and 8 after the infusion.

RESULTS

In the study, 56 out of 60 (93%) planned infusions were administered and 157 out of 168 (93%) clinical evaluations were successfully performed. The ultrasonic evaluation revealed that the utilized veins had a diameter of 2.15+/-0.8 mm (range, 1.0--4.4 mm). There were no signs of thrombophlebitis in any single vein.

CONCLUSION

Administration of a glutamine-containing dipeptide concentrate (20%) by peripheral veins is safe in terms of local tolerance, if a strict protocol is adapted for this purpose is used.

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.

Experimental infusion phlebitis: importance of titratableacidity on phlebitic potential of infusion solution

The titratable acidity of infusion solutions has never been taken into account in infusion phlebitis. This study aims to clarify the importance of titratable acidity on the phlebitic potential of infusion solutions. Solutions with different titratable acidity (from 0.16 to 12 mEq/L) were infused into the ear veins of 6 rabbits for 6 h at 10 mL/kg/h, and the veins were later examined histopathologically. Even at pH 4.0, a commercial 10% glucose solution scarcely caused any changes because of its very low titratable acidity (0.16 mEq/L). A 10% glucose solution with its titratable acidity adjusted to 3 mEq/L (pH 4.3) with citrate and NaOH, however, caused phlebitic changes in all 6 rabbits, and adjusting the titratable acidity to 12 mEq/L (pH 4.4) increased the degree of phlebitis. On the other hand, a 10% glucose solution with a pH of 5.4 and a titratable acidity of 6 mEq/L caused slight phlebitic changes in half the rabbits. These results suggest that 1) the titratable acidity of infusion solutions is important to the phlebitic potential when the pH is low, 2) when the pHs are similar, the phlebitic potential of infusion solutions depend on the titratable acidity, and 3) the phlebitic potential of infusion solutions can not be estimated by pH or titratable acidity alone.

Hypertension in infancy

Hypertension in infants is rare and requires a thorough evaluation. The incidence of hypertension in infancy has risen in recent years, reflecting both better monitoring methods and increasingly successful salvage of smaller and smaller newborns. Overall mortality and morbidity rates for uncontrolled hypertension in infants are unknown. With appropriate treatment, the prognosis for resolution of hypertension is good. In most cases, hypertension is short-lived and blood pressures return to normal even when medication is discontinued. Recent experience with improved antihypertensive agents in infancy has meant that nephrectomy for renovascular hypertension is rarely required. There is still much to learn about the indications for treatment of elevated blood pressures in infancy and the potential adverse effects of therapy. Infants with a history of neonatal hypertension should be followed closely because the long-term prognosis is not known and recurrence of hypertension remains a possibility. Because hypertension can develop in high-risk newborns following discharge from the nursery, these infants deserve routine blood pressure measurements as part of their outpatient follow-up.

Clinical predictors of intravenous site symptoms

The purpose of this prospective multi-site study was to determine the frequency of intravenous (IV) site symptoms and to develop a preliminary model of the factors implicated in the number of these symptoms. In a sample of 514 patients from four institutions, IV site symptoms including pain, redness, swelling, induration, and/or a venous cord were present in 205 (39.9%) of the patients. The IV catheters were in place an average of 48.7 hr. There were no significant differences in symptoms by hospital site. Using multiple regression techniques, a seven-factor model explained 18% of the variance in number of IV site symptoms. Further research is required to explore other potential causes for the numbers of IV site symptoms.

Venous access. Preoperative, operative, and postoperative dilemmas

The past two decades have seen a tremendous increase in the use of central venous catheters and its associated complications. The increased sophistication that physicians now have with regard to nutritional and metabolic needs has escalated the use of central venous catheters. As the acquired immunodeficiency syndrome epidemic grows, so too will the number of patients with infections and metabolic complications, many of whom will have conditions severe enough to benefit from the use of central venous catheters to deliver antimicrobial drugs and other supportive intravenous therapy. Our ability to sustain patients with short-bowel syndrome also relies critically on central venous access. Likewise, treatment of patients with leukemias and certain solid tumors frequently requires placement of these catheters. Central venous catheters are essential for bone marrow transplantation. Efforts to minimize the risks associated with placement of a central venous catheter by more frequent use of catheter exchange rather than another venipuncture should be encouraged when possible. Techniques to prevent arrhythmia during overinsertion of guide wires are also important. Vigilant searches for, and prompt treatment of, catheter-related sepsis and central vein thrombosis are critical. Better prophylaxis against the development of catheter-related sepsis and catheter-related thrombosis is also needed. Further prospective investigations should be performed, however, to define precisely cost-effective methods of detection and duration of therapy for patients with both catheter-related sepsis and catheter-related thrombosis. Further advances in the technology and management of catheters need to continue to meet these ongoing challenges.

Thrombogenicity of total parenteral nutrition solutions: II. Effect on induction of endothelial cell procoagulant activity

Thrombosis is a common sequela of total parenteral nutrition. We have recently demonstrated in vitro that hypertonic total parenteral nutrition solutions are potent inducers of a tissue factor monocyte procoagulant activity, the initiating cofactor of the extrinsic clotting cascade. We have further studied, in vitro, the effects of the component solutions of total parenteral nutrition on the induction and modulation of endothelial cell procoagulant activity. Cultured porcine aortic endothelial cells were incubated with (a) 200 microliters of dextrose solution (5%, 10%, 20%, 25%, and 50%), (b) 200 microliters of amino acid solution [full strength (N), one-fourth strength, and one-half strength], and (c) 200 microliters of 10% lipid emulsion. Cocultures of lipid emulsion and 20% dextrose, lipid emulsion and full-strength 10% amino acid solution (N-amino acid), and lipid emulsion and bacterial lipopolysaccharide also were studied. Cells were incubated for intervals of 3-108 h, washed and frozen, harvested, and assayed for endothelial cell procoagulant activity. Units of endothelial cell procoagulant activity were derived from a standard thromboplastin curve. Our results show that amino acid and hypertonic dextrose total parenteral nutrition solutions are able to strongly induce endothelial cell procoagulant activity expression in vitro. In contrast, lipid emulsion significantly inhibited the induction of endothelial cell procoagulant activity by 20% dextrose, N-amino acid, and lipopolysaccharide. These results provide further evidence for the role of the cellular pathways of coagulation in total parenteral nutrition-induced thrombosis. Furthermore, the inhibitory properties of lipid emulsion may be of practical advantage in reducing total parenteral nut induced thrombosis.

Central venous thrombosis related to the silastic Hickman-Broviac catheter in an oncologic population

The use of subcutaneously implanted, Dacron cuffed, central venous silastic catheters (Hickman/Broviac catheter [HC/BC]) has not eliminated catheter related-central venous thrombosis (CR-CVT). HC/BC related CR-CVT was identified and followed in 15 oncology patients. Median time period to CR-CVT was 155 days (range 15-638). No correlation was established to patient age, sex, diagnosis, coagulation status, use, longevity, technique, or site of placement. Fourteen patients were treated with anticoagulation and/or thrombolytic therapy. Of seven patients treated with HC/BC in situ, one required HC/BC removal to achieve CR-CVT resolution. Median follow-up post-CR-CVT was 362 days (range 34-1622). No patient suffered untoward long-term sequelae. Nine patients had 11 catheters placed following resolution of CR-CVT. None had repeat thrombosis. CR-CVT incidence in a single 12-month period was 3.7% (7/190). The placement of HC/BC in an oncology population is an acceptably safe method for long-term venous access.

Management of aortic thrombosis secondary to umbilical artery catheters in neonates

During the past ten years, we have surgically managed seven neonates who developed total occlusion of the distal aorta due to umbilical artery catheters. All patients experienced symptoms of congestive heart failure. Five patients presented with severe hypertension, and all of these had aortorenal involvement: three infants had aortorenal thrombosis and two infants had infrarenal aortoiliac thrombosis with suprarenal extension of thrombus. Two infants had aortoiliac thrombosis with clot confined to the infrarenal aorta. Aortic thrombosis imposes an additional severe hemodynamic insult in these already seriously ill infants. Survival in this group of patients depends upon prompt recognition of this problem, effective surgical correction, and careful perioperative management. Our experience suggests that this diagnosis should be entertained in the infant presenting suddenly with congestive heart failure, hypertension, or lower limb ischemia after umbilical artery catheterization. The diagnosis is preferably confirmed by real-time ultrasound and/or radionuclide flow scan, although aortography may sometimes be necessary. Surgical management includes early transabdominal aortotomy with thrombectomy. Prompt thrombectomy resulted in the survival of six patients. One infant died in acute renal failure. Renal function and leg perfusion is satisfactory in the remaining patients, although one child required later operative correction of renovascular hypertension. Two additional patients needed prolonged postoperative antihypertensive therapy for 14 to 34 months before this problem resolved. Long-term follow-up is necessary for managing renovascular hypertension and monitoring lower extremity perfusion.

Complications of intravenous therapy: reduction by buffering of intravenous fluid preparation

Local complicationn of intravenous infusions have become a common cause of morbidity in hospitals. Two consecutive groups of patients were studied: the patients in the first group had received standard non-buffered intravenous fluid preparations with pH from 3.6 to 6.0; the second group of patients received fluids which were buffered to a neutral pH. The incidence of local complications in the first group was high (58%), with phlebitis being the most common complication which occurred in 43% of patients. The addition of a buffer to the fluids just before the infusion reduced the incidence of all complications in the second group of patients to 28%, and that of phlebitis to 19%. It will be shown that the complications can be significantly reduced by buffering the infusion fluids.

Experimental infusion thrombophlebitis. Importance of the pH of glucose solutions

An experimental method is presented, which compares the tendency of different infusions to cause thrombophlebitis. It is based ona quantitative histological analysis of the inflammatory changes in the veins of rabbit ears after infusions under standardized conditions. By means of this method the inflammatory changes in the veins have been shown to be significantly less pronounced when the pH of glucose solutions is altered from 3.0 to 3.6. This pH change has been prescribed in the 1971 corrections to Pharmacopoea Nordica 1963. By complete neutralization of 5% glucose a further reduction of the damage to the veins has been obtained. For this purpose phosphate buffer is recommended.

Significant reduction in the incidence of phlebitis with buffered versus unbuffered cephalothin

Cephalothin (1 g every 2 h), buffered cephalothin, and diluent alone (5% dextrose in water) were each administered for 4 days intravenously to 12 volunteers in a double-blind crossover study. The incidence of phlebitis with buffered cephalothin was significantly lower than that with unbuffered drug (P < 0.01) and almost identical to the incidence with diluent alone.