Management of an i.v. fluid shortage through use of electronic medical record alerts.

PURPOSE: Evaluation of mechanisms used to cope with an i.v. fluid shortage to determine if prescribing habits were changed and if substitution of an i.v. dose of magnesium with an oral dose impacted patient outcomes. METHODS: A single-center, retrospective analysis of electronic medical record (EMR) alerts and medical records covering 6-month periods before and during an i.v. fluid shortage was conducted. Records of adult medical and surgical inpatients admitted during these periods who had an order for i.v. or oral magnesium were screened for inclusion. The primary outcome of part 1 of the study was the percent acceptance of drug shortage-related EMR alert recommendations associated with i.v. magnesium. The primary outcome of part 2 of the study was the change in serum magnesium concentration (SMC) after an i.v. or oral dose of magnesium was administered. RESULTS: Of the 7,476 EMR alerts generated during provider ordering of i.v. magnesium products, 4.8% resulted in the provider accepting the recommendation to switch to an oral alternative, 89% resulted in continuation of an i.v. magnesium order, and 6.2% resulted in order cancellation. Among patients who received magnesium doses, SMC values increased by a mean (SD) of 0.135 (0.08) mg/dL per gram of i.v. magnesium sulfate administered (n = 251), compared to an increase of 0.058 (0.08) mg/dL per 400-mg tablet of magnesium oxide administered (n = 42). CONCLUSION: Acceptance of the EMR alert recommendations was low. Both i.v. magnesium sulfate and oral magnesium oxide are viable options for increasing SMC.

Circulating Ionized Magnesium: Comparisons with Circulating Total Magnesium and the Response to Magnesium Supplementation in a Randomized Controlled Trial.

Ionized Mg (iMg) is considered the biologically active fraction of circulating total Mg (tMg). It is possible that iMg may be a more physiologically relevant marker than tMg. Using data from a double-blind pilot randomized controlled trial, we tested (1) whether oral Mg supplementation will increase iMg concentrations compared with placebo and (2) the relationship between iMg and tMg at baseline. Additionally, we evaluated the agreement between iMg measured in fresh whole blood versus stored samples. A total of fifty-nine participants were randomized 1:1 to oral Mg supplementation (400 mg/day, Mg Oxide) or placebo for 10 weeks. Fasting blood samples were obtained at baseline and follow-up. The analysis used linear regression and an intent-to-treat approach. Participants were generally healthy, the mean age was 62, and 73% were female. The baseline iMg and tMg were modestly and positively associated (r = 0.50). The ratio of baseline iMg to tMg was 64%. The mean supplement effect on iMg was 0.03 mmol/L (95% CI:0.01, 0.05) for Mg supplementation versus placebo. The supplement effect on iMg was not statistically significantly different according to baseline iMg status (above/below median). Compared to fresh blood, iMg was consistently higher in refrigerated and frozen samples by 0.14 and 0.20 mmol/L, respectively. In this relatively healthy adult population, Mg supplementation over 10 weeks resulted in increased iMg concentrations. Whether iMg is a more appropriate measure of Mg status than tMg, and the public health or clinical utility of measuring iMg remains to be determined.

Maternal Hypercholesterolemia Associated with Nicotine Exposure in Adulthood May Induce Kidney Injury in Male Rats if Hypomagnesemia Occurs.

BACKGROUND/AIMS: Maternal hypercholesterolemia is a risk factor to renal injury in rat pups at adulthood, especially if they feed a cholesterol-enriched diet after weaning. However, the renal function of male pups of dams with hypercholesterolemia (PH) that were fed a regular chow from weaning to adulthood needs investigation, particularly those exposed to an adverse risk such as nicotine. METHODS: We evaluated the renal function of PH animals and we compared the data with those found in male pups of control dams (PC) at 3- and 6-month-old by inulin clearance. Moreover, we investigated the effect of nicotine treatment for 8 days in both PH and PC animals at 6 months old via metabolic function studies and by renal histological analysis. RESULTS: Inulin clearance and other renal function parameters were similar in PH and PC animals at 3 and 6 months old. Nevertheless, the PH group showed significant differences with regard to histological analysis despite a similar number of glomeruli. The glomerular area of PH animals was significantly smaller than that measured in PC animals, and the fractional interstitial area was significantly larger in PH animals than that measured in PC animals at 3 months old. With regard to nicotine treatment, we observed a trend for a reduction in creatinine clearance in both PC and PH groups, but only PH animals showed hypomagnesemia and the highest fractional interstitial area. CONCLUSIONS: The offspring exposed to a high cholesterol milieu during intrauterine and neonatal life may show a silent kidney injury at adulthood that may be aggravated by nicotine exposure if hypomagnesemia occurs.

[Bowel obstruction-induced cholinergic crisis with progressive respiratory failure following distigmine bromide treatment].

A 54-year-old female experienced rapid respiratory failure while being transported in an ambulance to our emergency department for evaluation and management of constipation and abdominal pain. The patient was on treatment with distigmine bromide for postoperative urination disorder and magnesium oxide for constipation. Increased salivary secretions, diminished respiratory excursion, type 2 respiratory failure (PaCO2 : 65 mmHg), low serum cholinesterase, and hypermagnesemia were detected. Imaging studies revealed that the patient had bilateral aspiration pneumonia, fecal impaction in the rectum, and a distended colon causing ileus. The patient was mechanically ventilated and was weaned off the ventilator on day 3. Therapeutic drug monitoring after discharge revealed that the serum level of distigmine bromide on admission was markedly elevated (377.8 ng/mL vs. the normal therapeutic level of 5-10 ng/mL). Distigmine bromide induced a cholinergic crisis with a resultant increase in airway secretions and respiratory failure. In this particular case, orally administered distigmine bromide was excessively absorbed because of prolonged intestinal transit time secondary to fecal impaction and sluggish bowel movement; this caused a cholinergic crisis and hypermagnesemia contributing to respiratory failure. Clinicians should be aware that bowel obstruction in a patient treated with distigmine bromide can increase the risk of a cholinergic crisis.

Comparison of intravenous and oral magnesium replacement in hospitalized patients with cardiovascular disease.

PURPOSE: The results of an investigation of serum magnesium concentrations (SMCs) after i.v. versus oral delivery of magnesium in cardiovascular critical care are presented. METHODS: A retrospective case review was conducted to compare the net gain of magnesium after i.v. (n = 188) or oral (n = 164) magnesium therapy for the prevention of ventricular fibrillation and arrhythmias in patients hospitalized for serious cardiovascular disorders, as determined by assessing SMCs. The primary study outcome was the change from baseline SMC values 6-24 hours after the completion of magnesium courses; secondary outcomes included the impact of renal impairment, concomitant medication use, and other clinical variables on SMC changes. RESULTS: Although consistent elevations in SMC were produced by oral magnesium delivery, i.v. administration resulted in greater and more rapid elevations relative to baseline SMC. The degree of change in SMC was significantly influenced by the timing of SMC measurement after a magnesium course, by renal function, and by concomitant use of i.v. loop diuretics. CONCLUSION: A comparison of 24-hour courses of magnesium replacement therapy showed that magnesium sulfate 2 g i.v. was associated with larger changes in SMC than magnesium oxide 800, 1200, or 1600 mg orally when the baseline SMC was 1.4-1.8 mg/dL. At baseline SMCs of 1.4-1.8 mg/dL, oral magnesium oxide provided a consistent median increase in SMC of 0.1 mg/dL. The change in the number of bowel movements did not differ significantly between courses of i.v. magnesium sulfate and oral magnesium oxide.

Nanocrystalline titanium dioxide and magnesium oxide in vitro dermal absorption in human skin.

The dermal absorption potential of a nanocrystalline magnesium oxide (MgO) and titanium dioxide (TiO(2)) mixture in dermatomed human skin was assessed in vitro using Bronaugh-type flow-through diffusion cells. Nanocrystalline material was applied to the skin surface at a dose rate of 50 mg/cm(2) as a dry powder, as a water suspension, and as a water/surfactant (sodium lauryl sulfate) suspension, for 8 hours. Dermal absorption of nanocrystalline MgO and TiO(2) through human skin with intact, functional stratum corneum was not detectable under the conditions of this experiment.

Effects of oral magnesium supplementation on insulin sensitivity and blood pressure in normo-magnesemic nondiabetic overweight Korean adults.

BACKGROUND AND AIM: Little is known about the effect of magnesium on insulin sensitivity and BP in healthy individuals. Therefore, we investigated whether magnesium could improve insulin sensitivity and blood pressure (BP) in normo-magnesemic nondiabetic overweight adults. METHODS AND RESULTS: In a double-blinded, placebo-controlled, randomized trial, a total of 155 participants (BMI > or = 23 kg/m(2)) received either 12.3 mmol (300 mg) of elemental magnesium in the form of magnesium oxide (n=75) or placebo (n=80) each day for 12 weeks, constituting the intent-to-treat population. A repeated-measures ANOVA was used to evaluate the between-group changes in variables during the study. The baseline characteristics between the intervention and control groups were similar. There were no significant differences between the groups in the pattern of change of the homeostasis model assessment insulin resistance index, BP over time during the 12-week study. In subgroup analysis, magnesium supplementation (n=8, 27, and 24, respectively) lowered BP much more than placebo (n=16, 29, and 25, respectively) in those subjects whose systolic BP > or = 140 mmHg, diastolic BP 80-90 mmHg, and diastolic BP > or = 90 mmHg at the start of the study (P=0.016, 0.043, and 0.023, respectively); in comparison, those subjects whose initial BP reading was low at baseline did not show a change in BP. No significant adverse events related to magnesium supplementation were recorded. CONCLUSIONS: These results suggested that magnesium supplementation does not reduce BP and enhance insulin sensitivity in normo-magnesemic nondiabetic overweight people. However, it appears that magnesium supplementation may lower BP in healthy adults with higher BP.

Magnesium absorption by lactating dairy cows on a grass silage-based diet supplied with different potassium and magnesium levels.

The objective of the present study was to investigate the interactions of dietary K intake typical for forage-based diets on Mg balance in lactating dairy cows. Six lactating multiparous cows of the Swedish Red and White breed in midlactation were used. Two concentrations of Mg (1.9 and 4.3 g/kg of dry matter) and 3 concentrations of K (19, 28, and 37 g of K/kg of dry matter) were obtained by adding appropriate amounts of MgO and KHCO(3) to the diet. The experimental setup was a 6 x 6 Latin square design with a 2 x 3 factorial arrangement of treatments. Each experimental period lasted 14 d (9-d treatment adaptation period and 5-d data collection). There was no effect of Mg or K dietary supplementation on milk yield. Supplementing the ration with K did not significantly affect the Mg apparent absorption, urinary Mg excretion, or plasma Mg concentration. The Mg balance, estimated as the Mg losses in milk and urine, was positively related to Mg intake but not affected by K intake. The amount of apparently digested Mg was related to the Mg balance. The apparent digestibility ranged from 0.12 to 0.24 with no effect of mineral supplementation. There was a significant curvilinear relationship between plasma Mg and urinary Mg excretion, with a more marked increase in urinary Mg excretion at higher plasma levels of Mg.

[Familial hypomagnesemia with hypercalciuria and nephrocalcinosis. Association with ocular abnormalities]. / Hipomagnesemia familiar con hipercalciuria y nefrocalcinosis y asociación con alteraciones oculares.

BACKGROUND: Familial hypomagnesemia with hypercalciuria and nephrocalcinosis is an unusual disease that usually leads to end-stage renal failure. There is no specific treatment and, to a variable degree, patients with this disease present ocular abnormalities. The illness is due to a defect in the reabsorption of magnesium and calcium at the thick ascending limb of Henle because of a mutation of the PCLN-1 gene, which encodes a protein, paracellin-1, which intervenes in the reabsorption of both cations. OBJECTIVE: To review outcome and the incidence of ocular abnormalities in our patients and in cases described in Spain and to compare the incidence found with that in groups from other countries. METHOD: Retrospective study of a group of patients with familial hypomagnesemia with hypercalciuria and nephrocalcinosis diagnosed at a hospital. RESULTS: There were six girls and three boys with clinical symptoms of polyuria, polydipsia, and less frequently, urinary tract infections and lithiasis. All had hypomagnesemia, hypercalciuria and nephrocalcinosis. Five of the patients had renal failure at diagnosis and four underwent transplantation without recurrence. Eight patients had diverse ocular abnormalities. Eighty-one percent of Spanish patients had ocular abnormalities compared with 24 % of those from other countries. There was no evidence of successful medical treatment. CONCLUSIONS: Almost half of the patients presented chronic renal failure at diagnosis and most of the patients reached end-stage renal failure in the second or third decade of life. Normal glomerular filtration rate was found only in patients diagnosed at an early age. The most frequent extra-renal association in Spanish patients (81 %) corresponded to ocular abnormalities. Effective treatment consists of kidney transplantation that completely corrects the tubular disorder.

[The results of conservative treatment of oxalate urolithiasis in children]. / Wyniki leczenia zachowawczego kamicy szczawianowej u dzieci.

UNLABELLED: Hyperoxaluria is defined as urinary oxalate excretion exceeding 0.45 mmol/1.73 m2/day and accounts for 15% of recurrent urolithiasis. There have been only a few reports on the prevalence and treatment of oxalate urolithiasis in children. THE AIM: Of the study was to assess the efficacy and safety of the protocol of intensive and combined treatment of hyperoxaluria in children. MATERIAL AND METHODS: Seventeen children at the mean age of 11.5 +/- 4.5 years with positive history of urolithiasis and diagnosis of hyperoxaluria were studied. In this group hyperoxaluria was an isolated defect in 9 of 17 children, but in 3/17 it was accompanied by hyperuricosuria, in 5/17 by hypomagnesuria and in 1 case by hypercalciuria. During the 12-month period the children were intensively hydrated and received a low-oxalate diet and supplemental therapy with vitamin B6, magnesium, citrates and lactic acid bacteria preparations. RESULTS: In all but one child oxaluria decreased below 0.45 mmol/1.73 m2/day (decrease by 45%). No new stone formation was seen during the observation period. In all patients abdominal pain and haematuria subsided. CONCLUSIONS: We conclude that the intensive, complex, conservative treatment of hyperoxaluria in children is effective and safe. It allows to decrease hyperoxaluria and prevent the recurrence of urolithiasis.

Effect of magnesium on mRNA expression and production of endothelin-1 in DOCA-salt hypertensive rats.

The aim of this study was to investigate whether or not the decrease in blood pressure induced by dietary magnesium supplementation in DOCA-salt hypertensive rats is associated with modifications in expression and tissular production of endothelin-1. DOCA-salt treatment increased blood pressure, induced renal and cardiac hypertrophy, and increased endothelin-1 expression and production in the kidney, heart, and aorta. Mg supplementation for 8 weeks lowered blood pressure in DOCA-salt hypertensive rats and prevented hypertrophies and the increase of endothelin-1 expression and production in the heart, aorta, and kidney. Treatment with a receptor ETA antagonist, ABT-627, was used to clarify the relationship between the lowering effect of Mg supplementation on blood pressure and endothelin-1 production. When DOCA-salt rats were treated with ABT-627 for 8 weeks, Mg supplementation failed to lower blood pressure. In conclusion, these findings suggest that the lowering effect of Mg supplementation on blood pressure requires an inhibitory effect on endothelin-1 activity and/or endothelin-1 production in DOCA-salt hypertensive rats.

[Etio-pathogenetic mechanisms of recurrences of atrial fibrillation of toxic alcoholic origin]. / Etiopatogeneticheskie mekhanizmy retsidivirovaniia fibrilliatsii predserdii alkogol'no-toksicheskogo geneza.

The following conditions in patients with alcoholic cardiac involvement predispose to recurrences of atrial fibrillation: atrial dilatation, shortening of refractory period, slowing of atrial conduction, increased vulnerability to extra stimuli, appearance of fragmented electrical activity i.e. late atrial potentials on high resolution ECG, autonomic influences on the heart, hypokalemia and hypomagnesemia.