Feasibility and Safety of Peripheral Intravenous Administration of Vasopressor Agents in Resource-limited Settings

BackgroundVasopressors are conventionally administered through a central venous catheter (CVC) and not through a peripheral venous catheter (PVC) since the latter is believed to be associated with increased risk of extravasation. Placement of a CVC requires suitably trained personnel to be on hand, and in resource-limited settings, this requirement may delay placement. Because of this and in cases where suitably trained personnel are not immediately available, some clinicians may be prompted to utilise a PVC for infusing vasopressors. The objective of this study is to assess the feasibility and safety of vasopressors administered through a PVC.Materials and methodsPatients who received vasopressors through a PVC for more than one hour were included in a single centre, consecutive patient observational study. Patients with a CVC at the time of initiation of vasopressors were excluded. Data regarding the size, location of PVCs, dose, duration and number of vasopressors infused were recorded. The decision to place CVC was left to the discretion of the treating physician. Extravasation incidents, severity and management of such events were recorded.ResultsOne hundred twenty-two patients age 55(4) years [mean (SD)] were included in the study. The commonest PVC was of 18G calibre (57%), and the most common site of placement was the external jugular vein (36.5%). Noradrenaline was the most common vasopressor used at a dose of 10.6 (7) mcg/min [mean (SD)] and the median duration of nine hours (IQR: 6-14). CVC was placed most commonly due to an increasing dose of vasopressors after 4.5(4) hours [mean (SD)]. Grade 2 Extravasation injury occurred in one patient after prolonged infusion of fifty-two hours, through a small calibre (20G) PVC, which was managed conservatively without any sequelae.ConclusionVasopressors infused through a PVC of 18G or larger calibre into the external jugular, or a forearm vein is feasible and safe. Clinicians need to balance the safety of peripheral vasopressor infusion with the additional costs and complications associated with CVC in resource-limited settings.

THE EFFECT OF INTENSIVE DOGS INVASION BY DIROFILARIASIS ON THE MORPHOLOGICAL PICTURE OF BLOOD

New data were obtained when studying the effect of intensive dirofilariоsis invasion on the morphological composition of the blood corpus of infected dogs. Hematological studies were performed on 20 dogs infected intensively with microfilaria. Blood from dogs was taken from a forearm vein in test tubes with an anticoagulant. For research, 2 groups were formed: experimental and control. The experimental group (n=10) consisted of dogs that had microfilaria dirofilariasis in blood samples. The control group of dogs (n=10) was formed from agelminthous animals, in the blood of which there were no nematode microfilaria. Results. With intensive invasion of dirofilariоsis in blood samples of dogs, a decrease in the number of erythrocytes is observed by 3.03х1012/l, a decrease in hemoglobin concentration by 70.68 g/l. At the same time, the number of leukocytes in the hematological profile of experienced dogs increased by 14.68х109/l, and that of eosinophils by 497.44%, which indicates profound pathophysiological changes in the hematocrit. Conclusion With a high intensity of dirofilariasis in dogs, erythropenia, hypohemoglobinemia, leukocytosis, and eosinophilia appear strongly on the background of control.

BIOCHEMICAL COMPOSITION OF THE BLOOD OF DOGS ON THE BACKGROUND OF THE INFLUENCE OF INTENSIVE INVASION OF DIROFILARIASIS

Experimentally obtained new data in the study of the biochemical composition of blood of invasive dogs on the background of the influence of intensive invasion of dirofilariоsis. Biochemical blood tests were performed on 20 dogs intensively infected with microfilaria pathogens of dirofilariasis using standard methods. In the morning, blood from dogs was taken from the forearm vein in test tubes with an anticoagulant for a general blood test, in test tubes with a clotting activator – for biochemical studies. For the study were formed 2 groups: experimental and control. The experimental group (n = 10) consisted of dogs that had microfilariae of dirofilariоsis pathogens in blood samples. A control group of dogs (n = 10) was formed from nonhelminthic animals. Intensive dirofilariasis invasion has a pathological effect on the biochemical blood parameters of dogs in the form of an increase in total whey protein by 28.83 g / l, and enzymes: AST by 27.89 units / l and ALT 47.95 units / l, total bilirubin in 38.01 μmol / l and urea in 17.07 μmol / l. Against the background of control at high intensity of dirofilariasis invasion in dogs, hyperproteinemia with a multiple increase in the activity of AST and ALT, bilirubin and urea manifest with firmness.

Does sympathetic dysfunction occur before denervation in pure autonomic failure?

Pure autonomic failure (PAF) is a rare sporadic disorder characterized by autonomic failure in the absence of a movement disorder or dementia and is associated with very low plasma norepinephrine (NE) levels—suggesting widespread sympathetic denervation, however due to its rarity the pathology remains poorly elucidated. We sought to correlate clinical and neurochemical findings with sympathetic nerve protein abundances, accessed by way of a forearm vein biopsy, in patients with PAF and in healthy controls and patients with multiple systems atrophy (MSA) in whom sympathetic nerves are considered intact. The abundance of sympathetic nerve proteins, extracted from forearm vein biopsy specimens, in 11 patients with PAF, 8 patients with MSA and 9 age-matched healthy control participants was performed following a clinical evaluation and detailed evaluation of sympathetic nervous system function, which included head-up tilt (HUT) testing with measurement of plasma catecholamines and muscle sympathetic nerve activity (MSNA) in addition to haemodynamic assessment to confirm the clinical phenotype. PAF participants were found to have normal abundance of the NE transporter (NET) protein, together with very low levels of tyrosine hydroxylase (TH) (P<0.0001) and reduced vesicular monoamine transporter 2 (VMAT2) (P<0.05) protein expression compared with control and MSA participants. These findings were associated with a significantly higher ratio of plasma 3,4-dihydroxyphenylglycol (DHPG):NE in PAF participants when compared with controls (P<0.05). The finding of normal NET abundance in PAF suggests intact sympathetic nerves but with reduced NE synthesis. The finding of elevated plasma ratio of DHPG:NE and reduced VMAT2 in PAF indicates a shift towards intraneuronal NE metabolism over sequestration in sympathetic nerves and suggests that sympathetic dysfunction may occur ahead of denervation.