Indication of Treatment For Children And Adolescents With Postural Tachycardia Syndrome By Intravenous Saline Infusion

Background: Intravenous saline infusion is considered effective for the treatment of postural tachycardia syndrome (POTS) in adults. However, few studies have assessed the efficacy of intravenous saline infusion for POTS in children and adolescents. Aim: This study aimed to evaluate the efficacy of intravenous saline infusion in children and adolescents with POTS.Methods: A total of 107 children with POTS (median age: 13 years, range: 10–15 years) were enrolled. Eighty-eight children were in the intravenous saline infusion group and 19 children were in the comparison group. Blood pressure (BP) and pulse rate (PR) were recorded before and after standing. A standing test was performed early in the morning for 2 consecutive days. A volume of 1.5 L of saline was administered intravenously to each participant in the intervention group for a mean duration of 17 hours between the two standing tests.Results: The mean change in PR was significantly lower in the intervention group than in the comparison group during the second test (36.9 vs. 52.8 beats/minute, p<0.001). Additionally, the mean change in PR was significantly lower in the second test than in the first test (44.7 beats/minute) in the intervention group (p<0.001). However, the mean change in systolic BP was not different before and after intravenous saline infusion between the two groups or between the two tests in each group.Conclusion: Intravenous saline infusion reduces the increased PR on standing in children with POTS. Intravenous saline infusion improves tachycardia in children with POTS when standing.

The evaluation of psychogenic non-epileptic seizures (PNES) cases with saline injection method in video-EEG monitorization unit

ABSTRACT Background: It has been reported that 10 to 30% of patients sent to epilepsy centers with a diagnosis of refractory epilepsy are diagnosed with psychogenic non-epileptic seizure (PNES). A wide variety of provocative methods are used to assist PNES diagnosis. Objective: To investigate the effect of seizure induction on the diagnosis and prognosis of PNES. Methods: We retrospectively examined 91 patients with PNES complaints in our video-EEG laboratory. Intravenous saline was administered to all patients for induction of seizures. Results: Saline injection was performed in 91 patients referred to our EEG lab with PNES initial diagnosis, 57 of whom were female and 34 male. Saline injection triggered an attack in 82 patients (90%). Conclusions: In this study we have concluded that provocative methods are practical, cheap and, most of all, effective for patient diagnosis. In clinical practice, explaining the diagnosis is the first and most important step of the treatment, and careful patient-doctor communication has a positive impact on patient prognosis.

Cocaine-Induced Changes in Tonic Dopamine Concentrations Measured Using Multiple-Cyclic Square Wave Voltammetry in vivo

For over 40 years, in vivo microdialysis techniques have been at the forefront in measuring the effects of illicit substances on brain tonic extracellular levels of dopamine that underlie many aspects of drug addiction. However, the size of microdialysis probes and sampling rate may limit this technique’s ability to provide an accurate assessment of drug effects in microneural environments. A novel electrochemical method known as multiple-cyclic square wave voltammetry (M-CSWV), was recently developed to measure second-to-second changes in tonic dopamine levels at microelectrodes, providing spatiotemporal resolution superior to microdialysis. Here, we utilized M-CSWV and fast-scan cyclic voltammetry (FSCV) to measure changes in tonic or phasic dopamine release in the nucleus accumbens core (NAcc) after acute cocaine administration. Carbon-fiber microelectrodes (CFM) and stimulating electrodes were implanted into the NAcc and medial forebrain bundle (MFB) of urethane anesthetized (1.5 g/kg i.p.) Sprague-Dawley rats, respectively. Using FSCV, depths of each electrode were optimized by determining maximal MFB electrical stimulation-evoked phasic dopamine release. Changes in phasic responses were measured after a single dose of intravenous saline or cocaine hydrochloride (3 mg/kg; n = 4). In a separate group, changes in tonic dopamine levels were measured using M-CSWV after intravenous saline and after cocaine hydrochloride (3 mg/kg; n = 5). Both the phasic and tonic dopamine responses in the NAcc were augmented by the injection of cocaine compared to saline control. The phasic and tonic levels changed by approximately x2.4 and x1.9, respectively. These increases were largely consistent with previous studies using FSCV and microdialysis. However, the minimal disruption/disturbance of neuronal tissue by the CFM may explain why the baseline tonic dopamine values (134 ± 32 nM) measured by M-CSWV were found to be 10-fold higher when compared to conventional microdialysis. In this study, we demonstrated phasic dopamine dynamics in the NAcc with acute cocaine administration. M-CSWV was able to record rapid changes in tonic levels of dopamine, which cannot be achieved with other current voltammetric techniques. Taken together, M-CSWV has the potential to provide an unprecedented level of physiologic insight into dopamine signaling, both in vitro and in vivo, which will significantly enhance our understanding of neurochemical mechanisms underlying psychiatric conditions.

Transcranial Doppler in the Detection and Management of Arterial Vasospasm after Aneurysmal Subarachnoid Haemorrhage

Delayed cerebral ischaemia (DCI) and cerebral infarction is a much-feared complication of aneurysmal subarachnoid haemorrhage (aSAH). It has been largely attributed to focal hypoperfusion from reversible cerebral arterial narrowing, “vasospasm,” from the effects of prolonged exposure of the arteries to perivascular blood and oxy-haemoglobin. Transcranial Doppler (TCD) provides a non-invasive method for detecting and monitoring vasospasm. We report a 38-year-old lady who developed sudden dizziness and catastrophic generalised headache with neck pain (Pain Score 10/10) while voiding her bowels. She subsequently became drowsy and was brought to hospital. On examination, she was already alert and orientated. Blood pressure was 175/109 mm Hg. Her neurological examination was normal but for severe neck stiffness to passive flexion. Computed tomography of the brain showed extensive SAH. Cerebral angiography revealed a 6 × 3 mm aneurysm along the posteromedial aspect of the supraclinoid left internal carotid artery. She underwent aneurysm coiling that night. She was given intravenous and then oral nimodipine. TCD monitoring of the circle of Willis on day 14 detected very high velocities in the right and left middle cerebral arteries, mean velocity 187 and 141 cm/s, middle cerebral artery/internal carotid artery ratio 6.03 and 4.15, suggestive of severe and moderate vasospasm, respectively. She did not develop any related neurological symptoms or deficits. She was maintained in a euvolemic state and given high volumes of intravenous saline (2.4 L/day). Repeat TCD 7 days later was normal. The intravenous saline was gradually tailed off and she was subsequently discharged. TCD has an important role in the non-invasive detection and monitoring of vasospasm after aSAH.

SHORT-TERM EFFECTS OF APPROPRIATE EMPIRICAL ANTIMICROBIAL TREATMENT WITH CEFTOLOZANE/TAZOBACTAM IN A SWINE MODEL OF NOSOCOMIAL PNEUMONIA

The rising frequency of MDR/XDR pathogens is making more frequent the inappropriate empirical antimicrobial therapy (IEAT) in nosocomial pneumonia, which is associated with increased mortality. We aim to determine the short-term benefits of appropriate empirical antimicrobial treatment (AEAT) with C/T compared with IEAT with piperacillin/tazobactam(TZP) in MDR Pseudomonas aeruginosa (PA) pneumonia. Twenty-one pigs with pneumonia caused by XDR PA strain (susceptible to C/T but resistant to TZP) were ventilated up to 72h. Twenty-four hours after bacterial challenge, animals were randomized to receive 2-day treatment with either intravenous saline (untreated) or 50-25 mg/kg of C/T (AEAT) or 200-25 mg/kg of TZP (IEAT), every 8h. The primary outcome was the PA burden in lung tissue and the histopathology injury. PA burden in tracheal secretions and bronchoalveolar lavage (BAL) fluid, the development of antibiotic resistance and inflammatory markers were secondary outcomes. Overall PA lung burden was 5.30[4.00-6.30], 4.04[3.64-4.51], and 4.04[3.05-4.88] log10CFU/g in the untreated, AEAT and IEAT groups, respectively(p=0.299), without histopathological differences (p=0.556). In contrast, in tracheal secretions (p<0.001) and BAL fluid(p=0.002), bactericidal efficacy was higher in AEAT group. Increased minimum inhibitory concentration to TZP was found in 3 animals, while resistance to C/T did not develop. IL-1β was significantly downregulated by AEAT, in comparison to other groups(p=0.031). In a mechanically ventilated swine model of XDR P. aeruginosa pneumonia, appropriate initial treatment with C/T decreased respiratory secretions' bacterial burden, prevented development of resistance, achieved pharmacodynamic target and may reduce systemic inflammation. Yet, after only 2 days of treatment, P. aeruginosa tissue concentrations were moderately affected.

The place of hydration using intravenous fluid in patients at risk of developing contrast-associated nephropathy

There has been a significant rise in the incidence of contrast-associated nephropathy caused by administration of contrast media during cardiac interventions. This is one of the major complications of percutaneous coronary interventions, which may proceed to acute renal failure. Risk factors, including pre-existing renal dysfunction, older age and use of high osmolar contrast media, predispose patients to the development of contrast-associated nephropathy. Different risk-reduction strategies have been used to prevent contrast-associated nephropathy, including use of low osmolar contrast media, N-acetylcysteine, alkalisation of tubular fluid with intravenous sodium bicarbonate, and oral and intravenous hydration with isotonic solution. Hydration using intravenous saline is one of the main treatments used to prevent the development of nephropathy in patients receiving contrast media during cardiac interventions. Prehydration, before administering contrast media, seems to be crucial. The results of studies of the relative efficacy of sodium bicarbonate and/or N-acetylcysteine in reducing the development of contrast-associated nephropathy are not consistent and any beneficial effects may depend on the pre-existing state of the kidney. This review discusses hydration of patients who are at risk of developing contrast-associated nephropathy using intravenous fluid.

Abstract P147: Attenuation Of Diuretic And Natriuretic Responses To Acute Saline Volume Expansion In Mice Pre-treated With Tumor Necrosis Factor-alpha (TNFα) Inhibitor, Etanercept.

High salt intake induces an immune response that activates the mononuclear phagocyte system (MPS) cells to produce TNFα. We have previously demonstrated that intravenous infusion of TNFα in mice induces diuresis and natriuresis by inhibiting renal tubular sodium reabsorption. We hypothesize that the intravenous saline infusion can also induce the production of TNFα from MPS cells and such increase in TNFα influences saline induced natriuresis in the kidney. To examine this hypothesis, we measured the changes in TNFα levels in plasma and in urinary excretion rate (U TNFα V) during intravenous infusion of isotonic saline (0.9% NaCl), first at euvolemic condition (3 μL/min for 60 min; Baseline period) and then at an enhanced infusion rate (12 μL/min for 90 min; Volume expansion period) in anesthetized mice (n=5). Renal blood flow (RBF) and glomerular filtration rate (GFR) were measured by PAH and inulin clearances respectively. TNFα concentration in plasma and urine samples were determined using ELISA kit (Ebioscience, Woburn, MA). TNFα level in plasma collected during baseline period was undetectable, however, TNFα was increased to 3.7±1.3 pg/mL during volume expansion (VE) period. Baseline U TNFα V level was 0.01±0.002 pg/min/g (kidney wt), which was increased to 0.11±0.03 pg/min/g (P<0.05) during VE period. VE increased urine flow (V, 5.4±0.5 to 22.0±5.1 μL/min/g; P<0.05) and sodium excretion (U Na V; 0.54±0.19 to 4.84 ±1.16 μmol/min/g; P<0.05) without significant changes in RBF (7.1±1.0 to 6.0±1.8 mL/min/g) and GFR (1.18±0.11 to 0.94±0.28 mL/min/g). Interestingly, the diuretic and natriuretic responses to VE were markedly attenuated in mice (n=5) pretreated with a TNFα inhibitor, etanercept (ETN; 0.5 mg/kg intraperitoneally once daily for 3 days prior to the experiment day). VE induced changes in ETN treated mice are as follows: V, 5.9±0.65 to 7.9 ±1.6 μL/min/g; U Na V, 0.43±0.6 to 1.1±0.28 μmol/min/g; RBF, 5.4±0.4 to 6.6±0.9 mL/min/g and GFR, 0.87±0.09 to 0.98±0.13 mL/min/g. These findings demonstrate for the first time that an intravenous saline volume infusion resulted an increase in TNFα level in plasma and in urine. These results strongly suggest a physiological role for TNFα in regulating renal excretory function during saline volume expansion.