Pulmonary embolism in parenteral nutrition

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.

Social circumstances and medical complications in children with intestinal failure

Although most children discharged on home parenteral nutrition (HPN) will achieve enteral autonomy, some remain parenteral nutrition dependent; those who develop life-threatening complications may undergo small bowel transplantation (SBTx). The aim of this study was to investigate the relationship between social circumstances, compliance and complications.

SUBJECTS AND METHODS

An observational study in 2008-2012 on 64 children (34 HPN, 30 SBTx) from three units (two regional gastroenterology; one transplant). Social circumstances were assessed routinely as part of discharge planning; adherence by families to home care management was scored, and episodes of catheter-related blood stream infection and graft rejection were recorded for 2 years and related to compliance and social circumstances.

RESULTS

A quarter of families had a disadvantaged parent: non-English speaking (n=11), unable to read (n=5), physical disability (n=3), mental health problems disclosed (n=10); 20% children were cared for by a lone parent. Discharge home was delayed by social factors (n=9) and need for rehousing (n=17, 27%). 17/34 (50%) of HPN and 12/30 (40%) of transplant families were assessed as fully adherent. 10 families were assessed as non-adherent, eight were subject to child protection review and care was taken over by another family member (n=3) or foster parents (n=2). The risk of catheter-related blood stream infection was increased by parental disadvantage and age <3 years (p<0.05). Poor compliance was associated with complications in HPN and SBTx recipients.

CONCLUSIONS

Children receiving complex home care may be socially isolated and measures to support improved compliance such as increased community support, social care involvement and respite care may improve outcomes.

Intestinal absorption of lipid emulsion in premature infants: a pilot study

BACKGROUND

Adequate nutritional intake is essential in the very-low-birth-weight infant, but difficult to achieve in the first few postnatal days. Can lipids be given enterally in the first few days of life in sick preterm infants?

OBJECTIVE

To determine tolerance and absorption of lipid emulsion when fed enterally to very-low-birth-weight infants.

DESIGN/METHODS

Infants had a birth weight <1,500 g, an appropriate weight for gestational age, and were receiving parenteral nutrition. We performed a progressive series of studies, enrolling 5 infants in each group. Group 1 infants were fed enteral lipid emulsion at 1 g/kg/day for 4 days, starting when 60 ml/kg/day of breast milk was tolerated enterally. Simultaneously, a matched control group which received no oral lipid emulsion was enrolled. We then enrolled group 2 infants who were fed 3 g/kg/day with the same protocol as group 1. Group 3 infants were fed enteral lipid emulsion starting in the first 72 h of life. The infants were fed 1, 2 and 3 g/kg/day subsequently for 48 h each. Fat absorption was measured.

RESULTS

Gestational age was 24.6-30.8 weeks and birth weight was 620-1,400 g. One infant (group 1) developed necrotizing enterocolitis 1 week after the study. There were no other adverse clinical findings. On average, enteral lipid emulsion was started on day 8 of life in groups 1 and 2, and on day 2 in group 3. The intestinal lipid absorption was 93.6% (min. = 76%). There was no difference in fat absorption between the 4 groups (p > 0.05).

CONCLUSIONS

Lipid emulsions are an isotonic high-calorie source which can be given safely enterally instead of intravenously in the immediate neonatal period of very-low-birth-weight infants without clinical adverse effects and with almost complete absorption. There are potential advantages to oral administration of a lipid emulsion starting in early life which require further investigation.

Influence of the calcium concentration in the presence of organic phosphorus on the physicochemical compatibility and stability of all-in-one admixtures for neonatal use

BACKGROUND

Preterm infants need high amounts of calcium and phosphorus for bone mineralization, which is difficult to obtain with parenteral feeding due to the low solubility of these salts. The objective of this study was to evaluate the physicochemical compatibility of high concentrations of calcium associated with organic phosphate and its influence on the stability of AIO admixtures for neonatal use.

METHODS

Three TPN admixture formulas were prepared in multilayered bags. The calcium content of the admixtures was adjusted to 0, 46.5 or 93 mg/100 ml in the presence of a fixed organic phosphate concentration as well as lipids, amino acids, inorganic salts, glucose, vitamins and oligoelements at pH 5.5. Each admixture was stored at 4 degrees C, 25 degrees C or 37 degrees C and evaluated over a period of 7 days. The physicochemical stability parameters evaluated were visual aspect, pH, sterility, osmolality, peroxide formation, precipitation, and the size of lipid globules.

RESULTS

Color alterations occurred from the first day on, and reversible lipid film formation from the third day of study for the admixtures stored at 25 degrees C and 37 degrees C. According to the parameters evaluated, the admixtures were stable at 4 degrees C; and none of them presented precipitated particles due to calcium/phosphate incompatibility or lipid globules larger than 5 mum, which is the main parameter currently used to evaluate lipid emulsion stability. The admixtures maintained low peroxide levels and osmolarity was appropriate for parenteral administration.

CONCLUSION

The total calcium and calcium/phosphorus ratios studied appeared not to influence the physicochemical compatibility and stability of AIO admixtures.

Pulmonary function in rats dying from long‐term parenteral nutrition

Infusion of Vamin or Intralipid causes death in a rat model of continuous parenteral nutrition. Morphological investigations have shown vascular injury and thrombus formation in the lungs. In this study, lung function in rats was examined before death due to parenteral nutrition. The rats were fed saline intravenously (group I); 100 mL kg(-1) day(-1) (controls); a 7% amino acid-glucose solution (Vamin-Glukos) (group II); 100 mL kg(-1) day(-1), or 20% fat emulsion (Intralipid) (group III); 40 mL kg(-1) day(-1). The infusion was stopped when the condition of the rats deteriorated. In a saline-perfused, isolated lung model, pulmonary arterial pressure (Ppa), transpulmonary pressure (Ptp), endothelial function, measured as inactivation of serotonin (bioassay), and the capillary filtration coefficient (CFC) were determined. Haematological parameters were also evaluated. Constant findings in group II and III were central thrombus formation, anaemia and thrombocytopenia. Ppa increased from 0.7 (0.04) kPa in group I to 1.4 (0.1) kPa and 1.7 (0.1) kPa in groups II and III, respectively (p<0.001). Inactivation of serotonin was reduced to 36% (2) in group II and 37% (2) in group III compared with 74% (5) in group I (p<0.002). CFC increased to 25 mg min(-1) (5) (group II) and 30 mg min(-1) (6) (group III) compared with 13 mg min(-1) (2) in controls (p=0.01). The study shows that major pulmonary hypertension and severe reduction of the endothelial function are present when rats deteriorate after infusion of parenteral nutrition substrates.

Review of home paediatric parenteral nutrition on the UK

Home parenteral nutrition (HPN) is an expensive technological development which has given life to children with chronic intestinal failure. However, HPN is a complex therapy which carries life-threatening risks. The British Artificial Nutrition Survey (BANS), launched in 1996, monitors and audits HPN in the UK. It is the largest ongoing survey in the world, reviewing patients receiving enteral and parenteral nutrition. Data collated from health professionals between June 1996 and September 1999 identified 81 children who were registered. The commonest diagnosis for starting HPN was short-bowel syndrome, with 41% of the children being under the age of 1 year. Readmission rates of children to hospital were reported as less than 2%, suggesting that most of the burden of care is placed on families. Questionnaire data received from families (response rate 38%) identified that sleep disturbance was common. Families also experience a deterioration in their family life. This relates to poor social life activities and overall quality of life after the child had started HPN. Further qualitative research data are required to review the ongoing psychosocial issues for families.

Quality of life issues: parenteral nutrition to small bowel transplantation--a review

Parenteral nutrition (PN) has given life to patients with chronic intestinal failure who would otherwise have died. Home parenteral nutrition has improved the quality of life for many children. However, morbidity from this therapy remains significant with complications of line sepsis, lack of venous access, hepatic dysfunction, and pulmonary embolism. These complications are common in younger children. Detailed discussion must take place with the family regarding risks and benefits of PN. In those children developing complications of PN, intestinal transplantation is a logical extension of treatment. Early referral of patients for assessment is vital because significant mortality occurs when liver disease is established. Time is needed to counsel families on the potential benefits and risks of this treatment, including the physical and emotional demands made on the child and family. Overall worldwide survival for isolated small bowel transplantation is currently 50% and for combined small bowel and liver transplantation 40%. Significant complications are rejection, sepsis, and lymphoproliferative disease. Postoperative management can be complex and prolonged; child and parents require a great deal of physical and emotional support. The burden of care for parents decreases significantly after the first year. Small bowel transplantation offers a realistic alternative to PN. The choice of treatments is influenced by expected quality of life, which is just beginning to be evaluated.