A randomised study of the effects of osmolality and heparin with hydrocortisone on thrombophlebitis in peripheral intravenous nutrition

Intravenous nutrition administered via the central route incurs both the risks of catheter insertion and catheter related sepsis. Peripheral intravenous nutrition avoids these risks but is associated with a high risk of thrombophlebitis. We undertook a study to look at the incidence of thrombophlebitis caused by the infusion of a) a 'ready to use' mixture (Vitrimix KV) with an osmolality of 1130 mOsmol/kg, b) Vitrimix KV plus heparin and hydrocortisone, and c) a feed, with an osmolality of 700 mOsmol/kg, with heparin and hydrocortisone, to investigate the effects of the addition of heparin and hydrocortisone and the effect of osmolality on the incidence of thrombophlebitis. The addition of heparin (500 u/l) and hydrocortisone (5 mg/l) to Feed A significantly reduced the daily risk of thrombophlebitis from 0.43 to 0.11 episodes per patient, p < 0.01. A reduction in the osmolality resulted in a further fall in the incidence of thrombophlebitis to 0.04 episodes per patient with a significant increase in the median life span of the cannula from 26 h to 86 h, p < 0.02. Our data show that a low incidence of thrombophlebitis can be achieved by the use of a low osmolality feed with heparin and hydrocortisone. It is recommended that peripheral intravenous nutrition be used in patients who require nutritional support for less than 10 days.     

Fine bore silicone rubber and polyurethane catheters for the delivery of complete intravenous nutrition via a peripheral vein

The aim of the study was to evaluate two fine bore catheters for the delivery of complete intravenous nutrition (IVN), of osmolality 1250 mosm/kg, via a peripheral vein. 50 patients were randomised to receive either a 23G silicone rubber catheter or 22G polyurethane catheter. The median duration of feeding was 9 days for silicone rubber catheters and 10 days for polyurethane catheters. Silicone rubber catheters developed complications significantly more frequently (44%) than polyurethane catheters (22%, p < 0.05). There was no significant difference in the median life span of the catheters removed because of complications, nor in the daily risk of thrombophlebitis. 92% of patients who were fed through a polyurethane catheter required only a single catheter for the duration of IVN. The peripheral venous route should be the first choice when the administration of IVN is considered for a period of less than 2 weeks.     

Malnutrition and Cachexia in Heart Failure

Heart failure is a growing public health concern. Advanced heart failure is frequently associated with severe muscle wasting, termed cardiac cachexia. This process is driven by systemic inflammation and tumor necrosis factor in a manner common to other forms of disease‐related wasting seen with cancer or human immunodeficiency virus. A variable degree of malnutrition is often superimposed from poor nutrient intake. Cardiac cachexia significantly decreases quality of life and survival in patients with heart failure. This review outlines the evaluation of nutrition status in heart failure, explores the pathophysiology of cardiac cachexia, and discusses therapeutic interventions targeting wasting in these patients.     

Pathophysiological basis for thyrotoxicosis as an aggravating factor in post-ischemic brain injury in rats

The cross-sectional epidemiological studies investigating hyperthyroidism as a risk factor for hypertension and stroke are not conclusive. Several case studies, however, indicate that persistent thyrotoxicosis aggravates neurological damage subsequent to a stroke. To test the hypothesis, we measured physiological and biochemical parameters in a model of transient focal ischemia in rats with prior induction of thyrotoxicosis to investigate its effects. Age- and weight-matched rats were made hyperthyroid prior to middle cerebral artery (MCA) occlusion and killed after 3 days of reperfusion. We then estimated neurological deficit scores, body temperature, circulating total and free thyroxine (fT(4)) levels, lipid peroxide and thiol levels, and lactate dehydrogenase activity. While the standard 2-h occlusion of MCA resulted in very high mortality in hyperthyroid animals, the 30-min MCA occlusion resulted in a significant increase in neurological deficits compared with sham-operated animals. We observed a twofold or more increase in circulating fT(4) levels in rats receiving thyroxine. The increase in infarct size directly correlated with the increased dose of thyroxine. A significant thyroxine dose-dependent increase in lipid peroxide (malondialdehyde levels, P<0.05), lactate dehydrogenase activity (P<0.01), and a significant decrease in protective thiol levels (P<0.05) were observed. The data support our hypothesis that thyrotoxicosis is an independent risk factor which contributes to the aggravation of post-stroke injury and death. The study results indicate a need to control thyrotoxicosis in elderly populations to reduce the risk.     

Selection of monitoring site and outcome after neonatal coarctation repair

To assess whether simultaneous invasive arterial pressure monitoring of right upper and lower limbs in neonatal aortic coarctation with or without arch hypoplasia has an impact on surgical decision-making and outcome, data of 140 newborns who underwent emergency surgical repair over 15 years were analyzed retrospectively. The 36 who had simultaneous right arm and lower limb arterial pressure monitored intraoperatively were assigned to group 1. The other 104 who had blood pressure monitored invasively at a single site (either upper or lower limb) were allocated to group 2. In group 1, a residual gradient across the repaired segment was detected intraoperatively in 13% of patients, and corrected at the same sitting. In group 2, 6% needed subsequent balloon angioplasty. In all babies with arch hypoplasia in group 1, the proximal aortic cross clamp was readjusted at least once to avoid compromise of carotid blood flow. Simultaneous right upper and lower limb invasive pressure monitoring has an impact on the overall outcome in these sick neonates.