Beyond SEP-1 Compliance: Assessing the Impact of Antibiotic Overtreatment and Fluid Overload in Suspected Septic Patients

BACKGROUND

The Centers for Medicare and Medicaid Services (CMS) developed the Severe Sepsis and Septic Shock Performance Measure bundle (SEP-1) metric to improve sepsis care, but evidence supporting this bundle is limited and harms secondary to compliance have not been investigated.

OBJECTIVE

This study investigates the effect of an emergency department (ED) sepsis quality-improvement (QI) effort to improve CMS SEP-1 compliance, looking specifically at antibiotic overtreatment and harm from fluid resuscitation.

METHODS

This was a retrospective observational study conducted between March and July 2021 with patients for whom a sepsis order set was initiated. The primary outcomes included the number of patients treated with antibiotics who were ultimately deemed nonseptic and the number of patients who developed pulmonary edema, with or without need for positive pressure ventilation (PPV), within 48 h of receiving a 30 mL/kg fluid bolus. Data were collected via nonblinded chart reviews, with a free marginal κ-calculation indicating excellent interrater reliability.

RESULTS

The study cohort included 273 patients, 170 (62.3%) who were ultimately determined to be septic and 103 (37.7%) who were nonseptic. Of the 103 nonseptic patients, 82 (79.6%) received antibiotics in the ED. Of the 121 patients (44.3%) who received a 30 mL/kg bolus, 5 patients (4.1%) developed pulmonary edema and 0 of 121 patients required PPV within 48 h.

CONCLUSIONS

The QI effort led to moderate rates of antibiotic overtreatment and very few patients developed pulmonary edema due to a 30 mL/kg fluid bolus.

High Osmol Gap Hyponatremia Caused by Icodextrin: A Case Series Report

Recently, hyperosmolar hyponatremia following excessive off-label use of two exchanges of 2 L icodextrin daily during peritoneal dialysis (PD) was reported. We encountered a cluster of 3 cases of PD patients who developed hyperosmolar hyponatremia during on-label use of icodextrin. This appeared to be due to absorption of icodextrin since after stopping icodextrin, the serum sodium level and osmol gap returned to normal, while a rechallenge again resulted in hyperosmolar hyponatremia. We excluded higher than usual concentrations of specific fractions of dextrins in fresh icodextrin dialysis fluid (lot numbers of used batches were checked by manufacturer). We speculate that in our patients, either an exaggerated degradation of polysaccharide chains by α-amylase activity in dialysate, lymph, and interstitium and/or rapid hydrolysis of the absorbed larger degradation products in the circulation may have contributed to the hyperosmolality observed, with the concentration of oligosaccharides exceeding the capacity of intracellular enzymes (in particular maltase) to metabolize these products to glucose. Both hyponatremia and hyperosmolality are risk factors for poor outcomes in PD patients. Less conventional PD prescriptions such as off-label use of two exchanges of 2 L icodextrin might raise the risk of this threatening side effect. This brief report is intended to create awareness of a rare complication of on-label icodextrin use in a subset of PD patients and/or PD prescriptions.

Acetazolamide in Acute Decompensated Heart Failure with Volume Overload

BACKGROUND

Whether acetazolamide, a carbonic anhydrase inhibitor that reduces proximal tubular sodium reabsorption, can improve the efficiency of loop diuretics, potentially leading to more and faster decongestion in patients with acute decompensated heart failure with volume overload, is unclear.

METHODS

In this multicenter, parallel-group, double-blind, randomized, placebo-controlled trial, we assigned patients with acute decompensated heart failure, clinical signs of volume overload (i.e., edema, pleural effusion, or ascites), and an N-terminal pro-B-type natriuretic peptide level of more than 1000 pg per milliliter or a B-type natriuretic peptide level of more than 250 pg per milliliter to receive either intravenous acetazolamide (500 mg once daily) or placebo added to standardized intravenous loop diuretics (at a dose equivalent to twice the oral maintenance dose). Randomization was stratified according to the left ventricular ejection fraction (≤40% or >40%). The primary end point was successful decongestion, defined as the absence of signs of volume overload, within 3 days after randomization and without an indication for escalation of decongestive therapy. Secondary end points included a composite of death from any cause or rehospitalization for heart failure during 3 months of follow-up. Safety was also assessed.

RESULTS

A total of 519 patients underwent randomization. Successful decongestion occurred in 108 of 256 patients (42.2%) in the acetazolamide group and in 79 of 259 (30.5%) in the placebo group (risk ratio, 1.46; 95% confidence interval [CI], 1.17 to 1.82; P<0.001). Death from any cause or rehospitalization for heart failure occurred in 76 of 256 patients (29.7%) in the acetazolamide group and in 72 of 259 patients (27.8%) in the placebo group (hazard ratio, 1.07; 95% CI, 0.78 to 1.48). Acetazolamide treatment was associated with higher cumulative urine output and natriuresis, findings consistent with better diuretic efficiency. The incidence of worsening kidney function, hypokalemia, hypotension, and adverse events was similar in the two groups.

CONCLUSIONS

The addition of acetazolamide to loop diuretic therapy in patients with acute decompensated heart failure resulted in a greater incidence of successful decongestion. (Funded by the Belgian Health Care Knowledge Center; ADVOR ClinicalTrials.gov number, NCT03505788.).

Fluid Homeostasis and Diuretic Therapy in the Neonate

Understanding physiologic water balance and homeostasis mechanisms in the neonate is critical for clinicians in the NICU as pathologic fluid accumulation increases the risk for morbidity and mortality. In addition, once this process occurs, treatment is limited. In this review, we will cover fluid homeostasis in the neonate, explain the implications of prematurity on this process, discuss the complexity of fluid accumulation and the development of fluid overload, identify mitigation strategies, and review treatment options.

Arginine vasopressin and pathophysiology of COVID-19: An innovative perspective

In Covid-19, systemic disturbances may progress due to development of cytokine storm and dysregulation of and plasma osmolarility due to high release of pro-inflammatory cytokines and neuro-hormonal disorders. Arginine vasopressin (AVP) which is involve in the regulation of body osmotic system, body water content, blood pressure and plasma volume, that are highly disturbed in Covid-19 and linked with poor clinical outcomes. Therefore, this present study aimed to find the potential association between AVP serum level and inflammatory disorders in Covid-19. It has been observed by different recent studies that physiological response due to fever, pain, hypovolemia, dehydration, and psychological stress is characterized by activation release of AVP to counter-balance high blood viscosity in Covid-19 patients. In addition, activated immune cells mainly T and B lymphocytes and released pro-inflammatory cytokines stimulate discharge of stored AVP from immune cells, which in a vicious cycle trigger release of pro-inflammatory cytokines. Vasopressin receptor antagonists have antiviral and anti-inflammatory effects that may inhibit AVP-induced hyponatremia and release of pro-inflammatory cytokines in Covid-19. In conclusion, release of AVP from hypothalamus is augmented in Covid-19 due to stress, high pro-inflammatory cytokines, high circulating AngII and inhibition of GABAergic neurons. In turn, high AVP level leads to induction of hyponatremia, inflammatory disorders, and development of complications in Covid-19 by activation of NF-κB and NLRP3 inflammasome with release of pro-inflammatory cytokines. Therefore, AVP antagonists might be novel potential therapeutic modality in treating Covid-19 through mitigation of AVP-mediated inflammatory disorders and hyponatremia.

A narrative review of pharmacologic de-resuscitation in the critically ill

Despite evidence highlighting harms of fluid overload, minimal guidance exists on counteraction via utilization of diuretics in the de-resuscitation phase. While diuretics have been shown to decrease net volume and improve clinical outcomes in the critically ill, a lack of standardization surrounding selection of diuretic regimen or monitoring of de-resuscitation exists. Current monitoring parameters of de-resuscitation often rely on clinical signs of fluid overload, end organ recovery and other biochemical surrogate markers which are often deemed unreliable. The majority of evidence suggests that achieving a net-negative fluid balance within 72 h after shock resolution may be of benefit; however, approaches to such goal are uncertain. Loop diuretics are a widely available type of diuretic for removal of volume in patients with sufficient kidney function, with the potential for adjunct diuretics in special circumstances. At present, administration of diuretics within the broad critically ill population fails to find uniformity and often efficacy. Given the lack of randomized controlled trials in this susceptible population, we aim to provide a thorough therapeutic understanding of diuretic pharmacotherapy which is necessary in order to achieve desired goal of fluid balance and improve overall outcomes.

Sodium Fate after Sodium Bicarbonate Infusion: Influence of Altered Acid-Base Status

BACKGROUND

We have previously investigated the fate of administered bicarbonate infused as a hypertonic solution in animals with each of the 4 chronic acid-base disorders. Those studies did not address the fate of sodium, the coadministered cation.

METHODS

We examined baseline total body water (TBW), Na+ space, HCO3- space, and urinary sodium and bicarbonate excretion after acute hypertonic NaHCO3 infusion (1-N solution, 5 mmol/kg body weight) in dogs with each of the 4 chronic acid-base disorders. Observations were made at 30, 60, and 90 min postinfusion. Retained sodium that remains osmotically active distributes in an apparent space that approximates TBW. Na+ space that exceeds TBW uncovers nonosmotic sodium storage.

RESULTS

Na+ space approximated TBW at all times in normal and hyperbicarbonatemic animals (metabolic alkalosis and respiratory acidosis), but exceeded TBW by ~30% in hypobicarbonatemic animals (metabolic acidosis and respiratory alkalosis). Such osmotic inactivation was detected at 30 min and remained stable. The pooled data revealed that Na+ space corrected for TBW was independent of the initial blood pH but correlated with initial extracellular bicarbonate concentration (y = -0.01x + 1.4, p= 0.002). The fate of administered sodium and bicarbonate (internal distribution and urinary excretion) was closely linked.

CONCLUSIONS

This study demonstrates that hypobicarbonatemic animals have a Na+ space that exceeds TBW after an acute infusion of hypertonic NaHCO3 indicating osmotic inactivation of a fraction of retained sodium. In addition to an expanded Na+ space, these animals have a larger HCO3- space compared with hyperbicarbonatemic animals. Both phenomena appear to reflect the wider range of titration of nonbicarbonate buffers (Δ pH) occurring during NaHCO3- loading whenever initial [HCO3-]e is low. The data indicate that the fate of administered bicarbonate drives the internal distribution and the external disposal of sodium, the co-administered cation, and is responsible for the early, but non-progressive, osmotic inactivation of a fraction of the retained sodium.

Dermal Interstitial Alterations in Patients With Heart Failure and Reduced Ejection Fraction: A Potential Contributor to Fluid Accumulation?

BACKGROUND

Large networks of interstitial glycosaminoglycans help to regulate water and electrolyte homeostasis. The relation between dermal interstitial alterations and occurrence of edema in heart failure patients with reduced ejection fraction (HFrEF) is unknown. We hypothesize that in HFrEF patients (1) interstitial glycosaminoglycan density is increased, (2) changes in the interstitial glycosaminoglycan network are associated with interstitial fluid accumulation, and (3) there is a link between the interstitial glycosaminoglycan network and the renin-angiotensin-aldosterone system.

METHODS AND RESULTS

Two punch biopsies of the skin were obtained in healthy subjects (n=18) and HFrEF patients (n=29). Alcian blue staining and immunostaining for the angiotensin II type 1 receptor was performed. After obtaining tissue water content, total interstitial glycosaminoglycan (uronic acid) and sulfated glycosaminoglycan were quantified. A venous blood sample, clinical examination, and echocardiography were obtained. A significantly higher interstitial glycosaminoglycan content was observed in HFrEF patients compared with healthy subjects (uronic acid: 13.0±4.2 versus 9.6±1.6 μg/mg; P=0.002; sulfated glycosaminoglycan: 14.1 [11.7; 18.1] versus 10.0 [9.1; 10.8] μg/mg; P<0.001). Uronic acid and sulfated glycosaminoglycan density were strongly associated with tissue water content and peripheral edema (uronic acid: ρ=0.66; P<0.0001 and sulfated glycosaminoglycan: τ=0.58; P<0.0001). Expression of the angiotensin II type 1 receptor was found on dermal cells, although use of angiotensin-converting enzyme inhibitors/angiotensin receptor blocker was associated with significantly lower levels of interstitial glycosaminoglycans in HFrEF patients.

CONCLUSIONS

Interstitial glycosaminoglycan concentration is significantly increased in HFrEF patients compared with healthy subjects and correlated with tissue water content and clinical signs of volume overload. A better appreciation of the interstitial compartment might improve management of volume overload in HF.

[The pathway of vasopressin as a pharmacological target in nephrology: a narrative review]

ADH is a hormone secreted by neurohypophysis that plays different roles based on the target organ. At the renal level, this peptide is capable of causing electrolyte-free water absorption, thus playing a key role in the hydro-electrolytic balance. There are pathologies and disorders that jeopardize this balance and, in this field, ADH receptor inhibitors such as Vaptans could play a key role. By inhibiting the activation pathway of vasopressin, they are potentially useful in euvolemic and hypervolemic hypotonic hyponatremia. However, clinical trials in heart failure have not given favourable results on clinical outcomes. Even in SIADH, despite their wide use, there is no agreement by experts on their use. Since vaptans inhibit the cAMP pathway in tubular cells, their use has been proposed to inhibit cystogenesis. A clinical trial has shown favourable effects on ADPKD progression. Because vaptans have been shown to be effective in models of renal cysts disorders other than ADPKD, their use has been proposed in diseases such as nephronophthisis and recessive autosomal polycystic disease. Other possible uses of vaptans could be in kidney transplantation and cardiorenal syndrome. Due to the activity of ADH in coagulation and haemostasis, ADH's activation pathway by Desmopressin Acetate could be a useful strategy to reduce the risk of bleeding in biopsies in patients with haemorrhagic risk.

Predictability of tricuspid annular plane systolic excursion for the effectiveness of tolvaptan in patients with heart failure

BACKGROUND

There is no echocardiographic predictor of the effectiveness of tolvaptan in patients with heart failure (HF). The aim of this study was to investigate the echocardiographic predictor of responders to tolvaptan in patients with HF.

METHODS

This observational study consisted of 62 consecutive in-hospital patients with HF who received tolvaptan with volume overload despite standard therapies. The echocardiography data were obtained within 1 week before the administration of tolvaptan. Tolvaptan responders were defined as those having a body weight decrease from baseline >1 kg on the morning of day 8.

RESULTS

The mean age of the 62 patients was 75.1 ± 13.9 years, and 45 patients (72.6%) were considered to be responders. Tricuspid annular plane systolic excursion (TAPSE) was significantly higher (17.1 ± 3.8 vs. 13.0 ± 3.9 mm; p = 0.0004) and the tricuspid valve regurgitation pressure gradient (33.3 ± 14.6 vs. 44.9 ± 12.2 mmHg; p = 0.007) and estimated right atrium pressure (7.8 ± 4.2 vs. 10.3 ± 4.5 mmHg; p = 0.043) were significantly lower in the Responder group than in the Non-responder group. In a multivariate logistic regression analysis, TAPSE was found to be an independent predictor of response (odds ratio 1.28; 95% confidence interval 1.03-1.60). According to the receiver operating characteristics analysis, the area under the curve of TAPSE was the largest among the parameters measured by echocardiography. The cut-off value for TAPSE to predict responders was determined to be 17.0 mm (sensitivity = 56.8%, specificity = 94.1%).

CONCLUSIONS

TAPSE is a simple predictor of the effectiveness of tolvaptan in patients with HF.

[MODERN APPROACHES TO CORRECTION OF HYPERNATREMIA IN NEUROSURGICAL PATIENTS]

The article presents the analysis of the intensive therapy through the correction of persistent hypernatremia in neurosurgical patients after removal of brain tumors. The aim of this work was to evaluate the effectiveness of Sterofundin in the framework of complex therapy of hypernatremia in neurosurgical patients after removal of brain tumors. We analyzed the dynamics of the concentrations of sodium, potassium, chorus of the plasma, anion gap and buffer bases in the postoperative period of these patients. For obtaining reliable results, the patients were divided into groups according to the nature of the treatment: Sterofundin and symptomatic correction of hypotonic solution of sodium chloride, saluretic and Verospiron respectively. In a comparison between the groups, a distinct difference in the speed of regression of hypernatremia and durability of the achieved effect was observed. In case of treatment with Sterofundin there was a significant decrease of hypernatremia by the end of the second day of the postoperative period without tendency to re-raise. The prevalence of hypotonic solutions of sodium chloride and potassium-sparing saluretics in intensive care allowed reducing the sodium concentration non-persistently to the fourth day on the background of significant fluctuations in its concentration. The use of Sterofundin in complex therapy of electrolyte disturbances, particularly of hypernatremia in neurosurgical patients after removal of brain tumors, is reflected in the form of significant regression of increased sodium concentration in plasma compared with the method of use "hypotonic" hemodilution, saluretics and potassium-sparing diuretics.

Chronic Kidney Disease, Fluid Overload and Diuretics: A Complicated Triangle

BACKGROUND

Despite promising role of diuretics to manage fluid overload among chronic kidney disease (CKD) patients, their use is associated with adverse renal outcomes. Current study aimed to determine the extent of renal deterioration with diuretic therapy.

METHODS

A total 312 non-dialysis dependent CKD (NDD-CKD) patients were prospectively followed-up for one year. Fluid overload was assessed via bioimpedance spectroscopy. Estimated GFR (eGFR) was calculated from serum creatinine values by using Chronic Kidney Disease- Epidemiology Collaboration (CKD-EPI) equation.

RESULTS

Out of 312 patients, 64 (20.5%) were hypovolemic while euvolemia and hypervolemia were observed in 113 (36.1%) and 135 (43.4%) patients. Overall 144 patients were using diuretics among which 98 (72.6%) were hypervolemic, 35 (30.9%) euvolemic and 11 (17.2%) were hypovolemic. The mean decline in estimated GFR of entire cohort was -2.5 ± 1.4 ml/min/1.73m2 at the end of follow up. The use of diuretics was significantly associated with decline in eGFR. A total of 36 (11.5%) patients initiated renal replacement therapy (RRT) and need of RRT was more profound among diuretic users.

CONCLUSIONS

The use of diuretics was associated with adverse renal outcomes indicated by decline in eGFR and increasing risk of RRT initiation in our cohort of NDD-CKD patients. Therefore, it is cautiously suggested to carefully prescribe diuretics by keeping in view benefit versus harm for each patient.

Usefulness of portal vein pressure for predicting the effects of tolvaptan in cirrhotic patients

AIM: To elucidate influencing factors of treatment response, then tolvaptan has been approved in Japan for liquid retention.

METHODS: We herein conducted this study to clarify the influencing factors in 40 patients with decompensated liver cirrhosis complicated by liquid retention. Tolvaptan was administered at a dosage of 7.5 mg once a day for patients with conventional diuretic-resistant hepatic edema for 7 d. At the initiation of tolvaptan, the estimated hepatic venous pressure gradient (HVPG) value which was estimated portal vein pressure was measured using hepatic venous catheterization. We analyzed the effects of tolvaptan and influencing factors associated with treatment response.

RESULTS: Subjects comprised patients with a median age of 65 (range, 40-82) years. According to the Child-Pugh classification, class A was 3 patients, class B was 19, and class C was 18. Changes from the baseline in body weight were -1.0 kg (P = 2.04 × 10^-6) and -1.3 kg (P = 1.83 × 10^-5), respectively. The median HVPG value was 240 (range, 105-580) mmH₂O. HVPG was only significant influencing factor of the weight loss effect. When patients with body weight loss of 2 kg or greater from the baseline was defined as responders, receiver operating characteristic curve analysis showed that the optimal HVPG cutoff value was 190 mmH₂O in predicting treatment response. The response rate was 87.5% (7/8) in patients with HVPG of 190 mmH₂O or less, whereas it was only 12.5% (2/16) in those with HVPG of greater than 190 mmH₂O (P = 7.46 × 10^-4). We compared each characteristics factors between responders and non-responders. As a result, HVPG (P = 0.045) and serum hyaluronic acid (P = 0.017) were detected as useful factors.

CONCLUSION: The present study suggests that tolvaptan in the treatment of liquid retention could be more effective for patients with lower portal vein pressure.

Hypomagnesemia in Type 2 Diabetes: A Vicious Circle?

Over the past decades, hypomagnesemia (serum Mg(2+) <0.7 mmol/L) has been strongly associated with type 2 diabetes mellitus (T2DM). Patients with hypomagnesemia show a more rapid disease progression and have an increased risk for diabetes complications. Clinical studies demonstrate that T2DM patients with hypomagnesemia have reduced pancreatic β-cell activity and are more insulin resistant. Moreover, dietary Mg(2+) supplementation for patients with T2DM improves glucose metabolism and insulin sensitivity. Intracellular Mg(2+) regulates glucokinase, KATP channels, and L-type Ca(2+) channels in pancreatic β-cells, preceding insulin secretion. Moreover, insulin receptor autophosphorylation is dependent on intracellular Mg(2+) concentrations, making Mg(2+) a direct factor in the development of insulin resistance. Conversely, insulin is an important regulator of Mg(2+) homeostasis. In the kidney, insulin activates the renal Mg(2+) channel transient receptor potential melastatin type 6 that determines the final urinary Mg(2+) excretion. Consequently, patients with T2DM and hypomagnesemia enter a vicious circle in which hypomagnesemia causes insulin resistance and insulin resistance reduces serum Mg(2+) concentrations. This Perspective provides a systematic overview of the molecular mechanisms underlying the effects of Mg(2+) on insulin secretion and insulin signaling. In addition to providing a review of current knowledge, we provide novel directions for future research and identify previously neglected contributors to hypomagnesemia in T2DM.

Oral sodium and potassium binders in heart failure

Significant improvements in the morbidity and mortality associated with chronic heart failure have been gained with the use ACE inhibitors, angiotensin receptor blockers, mineralocorticoid receptor antagonists, and diuretics. However, the use of these agents is often limited by their propensity to precipitate worsening renal function and hyperkalemia, particularly in patients with chronic kidney disease. Several pharmacologic agents have been developed in recent years that utilize the gastrointestinal tract as an alternate route for drug absorption, electrolyte exchange, and drug and electrolyte elimination. The existing data establishing the safety and efficacy of these novel agents will be the focus of this review.

Increased incidence of diuretic use in critically ill obese patients

OBJECTIVE

Sodium retention occurs commonly in cardiac and liver disease, requiring the administration of diuretics to restore fluid balance. Whether obesity is associated with sodium retention has not been fully evaluated.

METHODS

In a large single-center cohort of critically ill patients, we evaluated whether admission body mass index was associated with the administration of either oral or intravenous diuretics during the intensive care unit (ICU) stay.

MAIN RESULTS

Of 7724 critically ill patients, 3946 (51.1%) were prescribed diuretics during the ICU stay. Overweight, class I obesity, and class II/III obesity were associated with a 1.35 (95% confidence interval [CI], 1.20-1.53; P < .001), 1.56 (95% CI, 1.35-1.80; P < .001), and 1.91 (95% CI, 1.61-2.26; P < .001) adjusted risk of receiving diuretics within the ICU, respectively. In adjusted analysis, a 5-kg/m(2) increment of body mass index was associated with a 1.19 (95% CI, 1.14-1.23; P < .001) increased adjusted risk of within-ICU diuretics. Among those patients receiving loop diuretics, obese patients received significantly larger daily diuretic doses.

CONCLUSION

Critically ill obese patients are more likely to receive diuretics during their stay in the ICU and to receive higher dosages of diuretics. Our data suggest that obesity is an independent risk factor for sodium retention.

Clinical indications for the albumin use: still a controversial issue

Human serum albumin (HSA) is the most abundant circulating protein and accounts for about 70% of the plasma colloid osmotic pressure. Beside the well known capacity to act as plasma-expander, HSA is provided of many other properties which are unrelated to the regulation of fluid compartmentalization, including binding and transport of many endogenous and exogenous substances, antioxidant function, immuno-modulation, anti-inflammatory activity, and endothelial stabilization. Treatment (hepatorenal syndrome) or prevention (renal failure after spontaneous bacterial peritonitis and post-paracentesis circulatory dysfunction after large volume paracentesis) of severe clinical complications in patients with cirrhosis and fluid resuscitation in critically ill patients, when crystalloids and non-proteic colloids are not effective or contra-indicated, represents the major evidence-based clinical indications for HSA administration. However, a large proportion of HSA prescription is inappropriate. Despite the existence of solid data against a real benefit, HSA is still given for nutritional interventions or for correcting hypoalbuminemia per se (without hypovolemia). Other clinical uses for HSA administration not supported by definitive scientific evidence are long-term treatment of ascites, nephrotic syndrome, pancreatitis, abdominal surgery, acute distress respiratory syndrome, cerebral ischemia, and enteric diseases. HSA prescription should be not uncritically restricted. Enforcement of clinical practice recommendations has been shown to allow a more liberal use for indications supported by strong scientific data and to avoid the futile administration in settings where there is a lack of clinical evidence of efficacy. As a result, a more appropriate HSA use can be achieved maintaining the health care expenditure under control.

[Basic principles in liquid electrolyte treatment]

Under normal physiological conditions, our body fluids and electrolytes are protected in complete balance in a wonderful, flawless design. Even small deviations occurring in this equilibrium may lead to impairments, which can end in death. Especially in fairly common sodium metabolism disorders, it is the responsibility of the clinician to determine, according to the patient's history and her physical examination of him, whether there is an excess or depletion of volume, and to arrange subsequent treatment. Serum sodium levels of 120, 140, or 150 mEq/L alone should be meaningless to the physician in relation to total body sodium and water content because either hyponatremia or hypernatremia can occur while the patient is hypovolemic, euvolemic, or hypervolemic. For example, administering hypertonic or isotonic saline treatment to a patient with hypervolemic hyponatremia in order to correct the sodium will clinically lead to both an increase in edema and a worsening of the hyponatremia. Treatment of hypo- and hypernatremia must be adjusted separately for each patient based on his age, presence of comorbid conditions, and the speed of development of the severity of clinical signs and symptoms. Adjustments either executed too slowly or too quickly will increase mortality or morbidity. For every patient presenting unexplained symptoms of the muscular, skeletal, or neurological systems, including confusion, making the first priority the conduction of electrolyte analyses and the correctly managed effective treatment of excesses or deficiencies may save lives and will certainly save time and money that would otherwise have been spent unnecessarily.

A novel target for diuretic therapy

The reabsorption of salt in the distal nephron is predominantly mediated via the thiazide-sensitive sodium chroride cotransporter, NCC (SLC12A3), and the chloride-bicarbonate exchanger pendrin (SLC26A4, PDS), with pendrin working in tandem with the epithelial sodium channel and NCC working by itself. Single deletion of NCC or pendrin in genetically engineered mouse models does not cause salt wasting or excessive diuresis under basal conditions. Both pendrin knockout and NCC knockout mice, however, show signs of volume depletion or develop hypotension during salt restriction. These findings have led investigators to conclude that pendrin and NCC are predominantly active during salt depletion and their contribution to salt reabsorption at baseline conditions is small. We hypothesized that pendrin may compensate for loss of NCC under basal conditions, thereby masking the role that each transporter plays in salt reabsorption. To test this hypothesis, double knockout of pendrin and sodium chloride cotransporter was generated by crossing animals with single deletion for NCC and pendrin. The double-knockout mice show significant salt and fluid wasting, along with severe volume depletion, metabolic alkalosis and prerenal failure under baseline conditions. Volume depletion, metabolic alkalosis and prerenal failure were significantly corrected with salt repletion. We conclude that pendrin plays an essential role in the distal tubule salt reabsorption in the setting of sodium-chloride cotransporter inactivation. We propose that pendrin could be a novel target for a new diuretic that in conjunction with thiazide can be an effective regimen for patients with fluid overload.

Electrolyte disturbances in patients with chronic heart failure--clinical, evolutive and therapeutic implications

Patients with heart failure are, by definition, hemodynamic unstable. Often, this condition may be accentuated by medication (digitalis, diuretics, antiarrhythmics), so that they become more sensitive to electrolyte disturbances, reacting sometimes violently with severe and life threatening rhythm troubles.

AIM

the evaluation of the incidence of electrolyte disturbances in patients diagnosed with chronic heart failure in order to establish a correlation with the evolution, prognosis and therapeutic implications.

MATERIAL AND METHODS

We analyzed retrospectively 100 patients diagnosed with chronic heart failure NYHA II-IV classes, admitted in Cardiology Clinic during 2009-2011. We analyzed electrolytic disturbances occurred during different strategies of therapy.

RESULTS

100 patients with heart failure were admitted in Cardiology Clinic during 2009-2011, 75 males and 25 females. Diagnosis was established by classical criteria. Evaluation was very complex and included: complete clinical examination, electrocardiogram, echocardiography, chest ray examination and biochemical analyses especially hepatic, renal function and electrolyte status.

CONCLUSIONS

The obtained data showed that electrolyte disturbances are frequent in patients with chronic heart failure, irrespectively of NYHA class. Hyperkalaemia, hypokalaemia and hyponatraemia are associated with diuretic therapy and may play a very important role in subsequent development of life-threatening arrhythmias.

[A practical treatment of hyponatraemia]

Hyponatraemia with cerebral symptoms is a medical emergency. Prompt management of airway, breathing and circulation together with repeated boluses of 2 ml/kg 3% NaCl constitute a rational treatment. The goal is remission of symptoms. After the initial correction, the main concern is to avoid overcorrection, thus reducing the risk of osmotic demyelination. P-[Na(+)] and diuresis must be measured frequently together with diuresis. Definitive treatment should be directed toward the aetiology.

[The role of disbalance of zinc and copper in school age children with community-aquired pheumonia]

The article analyzed 60 patients with community-aquired pneumonia from ages 6 to 18 years. The dependences of trace levels of zinc and copper in the serum of these children on the activity of the inflammatory process. Analysis of survey results showed that in children with community-aquired pneumonia was observed imbalance of trace elements Zn, Cu. Severity of such violations depended mainly on severity disease and to a lesser extent on age. Normalization of detected metabolic microelement content in a period of convalescence practically advancing. In children at acute stage of community-aquired pneumonia inflammation was observed with pronounced zinc deficiency (P < 0,001), and its content in blood serum is directly dependent on the acuity and severity of inflammation. Use of the drug, which contains zinc as part of adjuvant therapy in community-aquired pneumonia in children led to more rapid normalization of serum microelement parameters, apparently due to modulating effects on microelement status and immune status. To increase the effectiveness of treatment of community-aquired pneumonia in school-age children, its recommended to use zinc containing drug.

Intravenous diuretic day-care treatment for patients with heart failure

Fluid overload is a common manifestation of decompensated chronic heart failure. This paper reports on a pilot study that investigated whether intravenous (i.v.) furosemide administered on a cardiology day ward for three successive days was effective in improving the symptoms of patients with fluid overload and chronic heart failure. The results showed that 94.1% of patients reported an improvement in their breathlessness, with a marked weight loss in 88.2% of patients. There were no marked changes in blood pressure or renal function. Hospital admission was avoided in 94.1% of cases. The study concluded that i.v. diuretic treatment given in a hospital day-care setting is safe and effective, and that it reduces the need for hospital admissions. As a consequence, this reduces the associated financial costs of hospitalisation.

Cardio-renal syndrome: an entity cardiologists and nephrologists should be dealing with collegially

Heart failure may lead to acute kidney injury and vice versa. Chronic kidney disease may affect the clinical outcome in terms of cardiovascular morbidity and mortality while chronic heart failure may cause CKD. All these disorders contribute to the composite definition of cardio-renal syndromes. Renal impairment in HF patients has been increasingly recognized as an independent risk factor for morbidity and mortality; however, the most important clinical trials in HF tend to exclude patients with significant renal dysfunction. The mechanisms whereby renal insufficiency worsens the outcome in HF are not known, and several pathways could contribute to the "vicious heart/kidney circle." Traditionally, renal impairment has been attributed to the renal hypoperfusion due to reduced cardiac output and decreased systemic pressure. The hypovolemia leads to sympathetic activity, increased renin-angiotensin-aldosterone pathways and arginine-vasopressin release. All these mechanisms cause fluid and sodium retention, peripheral vasoconstriction and an increased congestion as well as cardiac workload. Therapy addressed to improve renal dysfunction, reduce neurohormonal activation and ameliorate renal blood flow could lead to a reduction in mortality and hospitalization in patients with cardio-renal syndrome.

[The homeostasis assessment by hemorrhagic shock]

The comparative analysis of different protocols of infusion therapy of the hemorrhagic shock stage III was performed. The infusion of the colloid solution of hydroxiethylstarch 200/0.5 and non-balanced crystalloid 0.9% solution of natrium chloride leads to the development of negative changes in homeostasis. Whereas infusion of the 4% solution of the modified gelatin and balanced crystalloid solition (sterofundin) allows to avoid the registered changes in electrolyte and alkaline balance.

[Cancer and electrolytes imbalance]

The electrolyte imbalance in advanced cancer patients, including hyperkalemia, hypercalcemia and hyponatremia, can be induced by various factors. Hyperkalemia is occasionally induced by chemotherapy for very large malignant tumors, due to tumor lysis syndrome. Hypercalcemia and hyponatremia are often observed in patients with breast cancer, renal cancer, prostate cancer, and the like, as a paraneoplastic syndrome. Some part of hypercalcemia results from osteolysis, but the majority is induced by hormonal factors, such as parathyroid hormone-related protein. One of the paraneoplastic causes of hyponatremia is antidiuretic hormone-producing tumor. These disorders could be morbid or even motile, resulting from encephalopathy or arrhythmia in some cases. However, it should be kept in mind that they could be improved or cured by prompt treatment. Recently, after approval of the molecular targeted drugs for epidermal growth factor receptors, such as cetuximab and panitumumab, the incidence of hypomagnesia with use of these monoclonal antibodies, is relatively frequent. In addition, small molecular targeted drugs, such as m-TORinhibitors and ABL kinase inhibitors, also exert adverse reactions including hypomagnesia and hypophosphatemia. Careful monitoring of the serum concentration of magnesium and phosphate ions, to which little attention was paid previously, is a key issue in these cases.

[Electrolyte and acid-base balance disorders in advanced chronic kidney disease]

1. The kidneys are the key organs to maintain the balance of the different electrolytes in the body and the acid-base balance. Progressive loss of kidney function results in a number of adaptive and compensatory renal and extrarenal changes that allow homeostasis to be maintained with glomerular filtration rates in the range of 10-25 ml/min. With glomerular filtration rates below 10 ml/min, there are almost always abnormalites in the body's internal environment with clinical repercussions. 2. Water Balance Disorders: In advanced chronic kidney disease (CKD), the range of urine osmolality progressively approaches plasma osmolality and becomes isostenuric. This manifests clinically as symptoms of nocturia and polyuria, especially in tubulointerstitial kidney diseases. Water overload will result in hyponatremia and a decrease in water intake will lead to hypernatremia. Routine analyses of serum Na levels should be performed in all patients with advanced CKD (Strength of Recommendation C). Except in edematous states, a daily fluid intake of 1.5-2 liters should be recommended (Strength of Recommendation C). Hyponatremia does not usually occur with glomerular filtration rates above 10 ml/min (Strength of Recommendation B). If it occurs, an excessive intake of free water should be considered or nonosmotic release of vasopressin by stimuli such as pain, anesthetics, hypoxemia or hypovolemia, or the use of diuretics. Hypernatremia is less frequent than hyponatremia in CKD. It can occur because of the provision of hypertonic parenteral solutions, or more frequently as a consequence of osmotic diuresis due to inadequate water intake during intercurrent disease, or in some circumstance that limits access to water (obtundation, immobility). 3. Sodium Balance Disorders: In CKD, fractional excretion of sodium increases so that absolute sodium excretion is not modified until glomerular filtration rates below 15 ml/min (Strength of Recommendation B). Total body content of sodium is the main determinant of extracellular volume and therefore disturbances in sodium balance will lead to clinical situations of volume depletion or overload: Volume depletion due to renal sodium loss occurs in abrupt restrictions of salt intake in advanced CKD. It occurs more frequently in certain tubulointerstitial kidney diseases (salt losing nephropathies). Volume overload due to sodium retention can occur with glomerular filtration rates below 25 ml/min and leads to edema, arterial hypertension and heart failure. The use of diuretics in volume overload in CKD is useful to force natriuresis (Strength of Recommendation B). Thiazides have little effect in advanced CKD. Loop diuretics are effective and should be used in higher than normal doses (Strength of Recommendation B). The combination of thiazides and loop diuretics can be useful in refractory cases (Strength of Recommendation B). Weight and volume should be monitored regularly in the hospitalized patient with CKD (Strength of Recommendation C). 4. Potassium Balance Disorders: In CKD, the ability of the kidneys to excrete potassium decreases proportionally to the loss of glomerular filtration. Stimulation of aldosterone and the increase in intestinal excretion of potassium are the main adaptive mechanisms to maintain potassium homeostasis until glomerular filtration rates of 10 ml/min. The main causes of hyperkalemia in CKD are the following: Use of drugs that alter the ability of the kidneys to excrete potassium: ACEIs, ARBs, NSAIDs, aldosterone antagonists, nonselective beta-blockers, heparin, trimetoprim, calcineurin inhibitors. Determination of serum potassium two weeks after the initiation of treatment with ACEIs/ARBs is recommended (Strength of Recommendation C). Routine use of aldosterone antagonists in advanced CKD is not recommended (Strength of Recommendation C). Abrupt reduction in glomerular filtration rate: Constipation. Prolonged fasting. Metabolic acidosis. A low-potassium diet is recommended with GFR less than 20 ml/min, or GFR less than 50 ml/min if drugs that raise serum potassium are taken (Strength of Recommendation C). In the absence of symptoms or electrocardiographic abnormalities, review of medications, restriction of dietary potassium and use of oral ion exchange resins are usually sufficient therapeutic measures (Strength of Recommendation C). If symptoms and/or electrocardiographic abnormalities are present, the usual parenteral pharmacological measures should be used (10% calcium gluconate, insulin and glucose, salbutamol, resins, diuretics) (Strength of Recommendation A). Parenteral bicarbonate and ion exchange resins in enemas are not recommended as first-line treatment (Strength of Recommendation C). Hemodialysis should be considered in patients with glomerular filtration rates below 10 ml/min (Strength of Recommendation C). 5. Acid-Base Disorders in CKD: Moderate metabolic acidosis (Bic 16-20) mEq/L is common with glomerular filtration rates below 20 ml/min, and favors bone demineralization due to the release of calcium and phosphate from the bone, chronic hyperventilation, and muscular weakness and atrophy. Its treatment consists of administration of sodium bicarbonate, usually orally (0.5-1 mEq/kg/day), with the goal of achieving a serum bicarbonate level of 22-24 mmol/L (Strength of Recommendation C). Limitation of daily protein intake to less than 1 g/kg/day is also useful (Strength of Recommendation C). Use of sevelamer as a phosphate binder aggravates metabolic acidosis since it favors endogenous acid production and therefore acidosis should be monitored and corrected if it occurs (Strength of Recommendation C). Hypocalcemia should always be corrected before metabolic acidosis in CKD (Strength of Recommendation B). Metabolic acidosis is an infrequent disorder and requires exogenous alkali administration (bicarbonate, phosphate binders) or vomiting.

Cisplatin-induced hypomagnesemia and cardiac dysrhythmia

We describe a case of a patient with cisplatin-induced hypomagnesemia who suffered brief asystole during an episode of gastroenteritis. Structural heart disease was excluded. The patient achieved complete clinical recovery after short-term administration of intravenous magnesium supplementation. Cisplatin should be considered a cause of hypomagnesemic-related cardiac dysrhythmia. Magnesium deficit may increase myocardial electrical instability and thus, the risk of life-threatening arrhythmias and sudden death. Long-term serum electrolyte measurement and appropriate replacement of magnesium are recommended.

Water in health and disease: new aspects of disturbances in water metabolism

Vasopressin is a critical regulator of water homeostasis. There are two major receptors for vasopressin: V1 and V2 receptors. Disturbances in water balance are commonly encountered in clinical practice and can be divided into disorders of urinary dilution and concentration. The major representatives of such disorders are diabetes insipidus and the syndrome of inappropriate secretion of antidiuretic hormone (SI ADH). Recent studies show that genetic forms of nephrogenic diabetes insipidus are due to mutations in the genes coding for the vasopressin V2 receptor (V2R) or aquaporin-2 (AQP2). Identification of the genes involved and analysis of the cellular fate of the V2R and AQP2 mutants are relevant for understanding the functioning of the V2R and AQP2 protein. These developments also have implications for future therapeutic options. The development of nonpeptide vasopressin receptor antagonists (VRAs) offers prospects for the treatment of euvolaemic (SI ADH) or hypervolaemic hyponatraemia (congestive heart failure or cirrhosis). Several nonpeptide VRAs are now in various stages of clinical trials. At present, only conivaptan is registered by the FD A for intravenous treatment of euvolaemic and hypervolaemic hyponatremia. A recent long-term study comparing tolvaptan with placebo in patients with chronic heart failure showed no reduction in risk of death and hospitalisation.

Evaluation and management of hyponatremia: an emerging role for vasopressin receptor antagonists

Vasopressin-2 receptor antagonists, collectively known as the 'vaptans', provide a new approach to the treatment of hyponatremia; therefore, an updated Review of the pathophysiology of hyponatremia is particularly timely. After briefly defining hyponatremia and introducing its clinical aspects and complications, we present an approach to the diagnosis and evaluation of hyponatremia that is based primarily on the often-underused concept of free water clearance and, more specifically, the electrolyte-free water clearance. Then we review the use of vasopressin receptor antagonists in the management of hyponatremia from the standpoint of their pharmacology, their mechanism of action, and available efficacy data from clinical trials.

Vasopressin antagonists

Effects of vasopressin via V1a- and V2-receptors are closely implicated in a variety of water-retaining diseases and cardiovascular diseases, including heart failure, hyponatraemia, hypertension, renal diseases, syndrome of inappropriate antidiuretic hormone secretion, cirrhosis and ocular hypertension. As vasopressin receptors are found in many different tissues, vasopressin antagonists may benefit the treatment of disorders such as cerebral ischaemia and stroke, Raynaud's disease, dysmenorrhoea and tocolytic treatment. V1b selective vasopressin antagonists are discussed in terms of their usefulness in the treatment of emotional and psychiatric disorders. The vaptans are vasopressin receptor antagonists with V1a (relcovaptan) or V2 (tolvaptan, lixivaptan) selectivity or non-selective activity (conivaptan) which may be advantageous in some disorders. The V1a/V2 non-selective vasopressin antagonist conivaptan is the first vaptan which is approved by the FDA for the treatment of euvolaemic hyponatraemia.

[The diuretic in chronic cardiac failure: a clumsy partner]

Ever since the publication of the large scale clinical trials of morbid-mortality, the recommendations concerning the medical treatment of cardiac failure are clear with respect to ACE inhibitors, betablockers, angiotensin receptor antagonists and aldosrerone antagonists with established target doses. As far as the prescription of diuretics go, drugs which are effective in a condition associated with a poor quality of life, it is important to use the minimal dosage because of their deleterious stimulant effects on the rennin-angiotensin-aldosterone system and their metabolic side effects. A review of the clinical trials shows that almost all patients were prescribed diuretics; in over 80% of cases, the drugs are loop diuretics with a preference for furosemide, with increasing doses during the follow-up, infrequently associated with thiazide diuretics. In the short term, diuretics reduce the circulating volume and the BNP. In the long term, high doses are associated with a poor prognosis. The clinician then has to decide on the basis of few objective criteria, especially for the reduction of dosage, despite the introduction of the BNP whose role as an aid to prescription remains to be defined. In addition to the simple prescription of drugs, a global approach to patient management is necessary in cardiac failure; in this context, concerning salt- water equilibrium and diuretics, therapeutic education may have a solid role to play to provide an acceptable quality of life including the reduction of the number of frequent hospital admissions.

Therapeutic approach in patients with dysnatraemias

BACKGROUND

Rapid correction of dysnatraemias is frequently associated with increased morbidity and mortality. Therefore, it is important to estimate the proper volume and type of infusate required to change the serum sodium concentration predictably. The aim of this study is to evaluate the utility or/and the accuracy of the Adrogue-Madias formula in managing patients with hyponatraemia and hypernatraemia.

METHODS

Among the 317 patients who either on admission to our internal medicine clinic or during their hospitalization were found to have hyponatraemia or hypernatraemia, we studied 189 patients (59.6%) in whom the administration of intravenous solutions was required for the correction of dysnatraemias.

RESULTS

Twelve hours after starting the administration of intravenous solutions the anticipated as well as the achieved serum sodium concentration were as follows: in volume depleted patients 130.2+/-4.1 vs 131.3+/-5.2 meq/l (n = 45; P = NS), in syndrome of inappropriate antidiuretic hormone secretion (SIADH) patients 127.4+/-5.7 vs 128.9+/-5.9 meq/l (n = 10; P = NS), in patients with diuretic-induced hyponatraemia 123.8+/-6 vs 125.5+/-5.6 meq/l (n = 29; P = NS), in patients with primary polydipsia 122.5+/-0.7 vs 129+/-1.4 meq/l (n = 2; P = 0.02), while in patients with hypernatraemia 153.6+/-7.5 vs 156.5+/-8.9 meq/l (n = 92; P = 0.021). Furthermore, 24 h from the initiation of the therapeutic intervention the expected and the achieved serum sodium concentrations were 130+/-4 vs 135.6+/-3.3 meq/l (n = 15; P = 0.002) in patients with volume depletion, 128.1+/-4.8 vs 130+/-4.5 meq/l (n = 15; P = NS) in patients with diuretic-induced hyponatraemia and 151.5+/-6.4 vs 153.3+/-8.3 meq/l (n = 67; P = NS) in patients with hypernatraemia.

CONCLUSIONS

The formula that has been proposed by Adrogue and Madias predicted with relative accuracy the changes in serum sodium concentration in almost all patients. Thus, it should be considered as a very useful tool for the management of dysnatraemias. However, special attention should be paid when this equation is used in patients with hyponatraemia due to extracellular volume depletion after euvolaemia's restoration and primary polydipsia in order to avoid rapid correction of hyponatraemia.

Assessing the metabolic and clinical consequences of early enteral feeding in the malnourished patient

BACKGROUND

It is often thought that enteral feeding should be initiated slowly in those who are severely malnourished. This descriptive study examined the effect of an enteral feeding protocol on the typical metabolic consequences seen in refeeding syndrome.

METHODS

A retrospective chart review was conducted on 51 patients who had been placed on hospital-wide enteral feeding and electrolyte replacement protocols over a 9-month period to determine whether there were any negative clinical consequences to early feeding.

RESULTS

Goal feeding rate was achieved within 17.6 +/- 8.7 hours. Forty patients (80%) developed depletions in phosphate, magnesium, or potassium after initiation of enteral feeding, including 93% of those deemed "at risk" and 74% of those "not at risk." All patients received electrolyte replacement according to protocols, and no patients showed any negative clinical effect.

CONCLUSIONS

This study showed that malnourished patients at risk for refeeding syndrome can be fed early without observed negative clinical consequences. An electrolyte replacement protocol may be an effective means of minimizing the electrolyte imbalances associated with early feeding. It also demonstrated the significance of applying such protocols to all patients requiring enteral support, as current methods of assessing "risk"for refeeding syndrome may be inadequate.

Brain dysfunction in uremia: a question of cortical hyperexcitability?

OBJECTIVE

To investigate whether patients with end-stage renal disease (ESRD) in different stages of the disease and undergoing different treatments display alterations in cortical excitability.

METHOD

A total of 36 patients with ESRD were evaluated at different stages of the disease and under different treatment by using standard transcranial magnetic stimulation (TMS) parameters. Moreover patients under haemodialysis underwent a double-blind crossover study (mannitol vs placebo) in order to better elucidate the pathophysiology of the acute effects of haemodialysis on cortical excitability.

RESULTS

Patients with ESRD in conservative therapy showed a significant reduction of short-interval intra-cortical inhibition (SICI). This alteration could be reversed by haemodialysis, peritoneal dialysis and by renal transplantation. After haemodialysis there was a significant increase of intra-cortical facilitation (ICF) inversely correlated with the drop in plasma osmolarity induced by the dialytic procedure. Mannitol infusion prevented the drop in plasma osmolarity and the haemodialysis-related changes in ICF.

CONCLUSIONS

ESRD patients showed alterations in cortical excitability that can be reversed by replacement therapies. We propose that the drop in plasma osmolarity is a key to the mechanism underlying post-haemodialysis cortical hyperexcitability.

SIGNIFICANCE

The results of this study give further insight to the pathophysiology of brain abnormalities in patients with chronic renal failure.

Intensity and focus of heart failure disease management after hospital discharge

BACKGROUND

Although features of heart failure disease management programs are broadly outlined, little is known about which interventions are actually used in the outpatient setting or which patients are most likely to require interventions.

METHODS AND RESULTS

Between September 2001 and June 2002, we enrolled 32 patients admitted to the Brigham and Women's Hospital Heart Failure Services, Boston, Mass, with decompensated heart failure. The intensity of care and outcomes of these patients were prospectively tracked for more than 90 days. During this time, there were 325 patient contacts (median 8.5 per patient), including 247 calls (median 7 per patient) and 78 clinic visits (median 2 per patient). Brigham and Women's Hospital clinicians adjusted diuretics a total of 109 times (median 2.5 times per patient). When frequency of diuretic adjustments was used to estimate the intensity of care, higher values of blood urea nitrogen at discharge predicted an increased intensity of care during the 90-day follow-up (relative risk [RR] 1.2, 95% confidence interval [CI] 1.0-1.3, P = .02). When frequency of clinic visits, telephone calls, and diuretic adjustments were used to estimate intensity of care, discharge creatinine (RR 1.03, 95% CI 0.99-1.06, P = .05), discharge blood urea nitrogen (RR 1.13, 95% CI 1.04-1.23, P = .004), and length of stay (RR 1.07, 95% CI 1.00-1.13, P = .04) were predictors of the composite end point.

CONCLUSIONS

Even after undergoing optimization of medications during admission for acute heart failure, patients in a comprehensive disease management program required frequent interventions to maintain clinical stability. Renal dysfunction was the strongest predictor of increased interventions and worse outcome.

Oliguria, Volume Overload, Na+ Balance, and Diuretics

This article discusses the pathophysiology and treatment of common fluid and electrolyte disorders in the ICU. The presence of oliguria should alert the intensivist to identify the underlying cause rather than to resort reflexively to measures, such as diuretics or dopamine, to establish urine flow. Hypo- and hypernatremia, which are exceedingly commonly in the ICU setting, also are discussed using a pathophysiologic approach.

Aminophylline as an adjunct diuretic for neonates--a case series

Aminophylline is an adenosine receptor antagonist. Adult and paediatric studies have demonstrated a diuretic effect of aminophylline due to increased renal blood flow and the inhibition of solute reabsorption in various segments of the nephron. We report a case series of five infants with volume overload despite frusemide treatment. Aminophylline was successfully used as an adjunct diuretic with increased urine output and effective weight loss occurring in all five neonates following its introduction.

Aldosterone resistance in kidney transplantation is in part induced by a down-regulation of mineralocorticoid receptor expression1

BACKGROUND

After renal transplantation immunosuppressive drugs-like cyclosporin A (CsA) and FK506 induce either hypoaldosteronism or pseudo-hypoaldosteronism presenting with hyperkalemia and metabolic acidosis. We investigated the relationship between renal allograft function under CsA therapy and plasma aldosterone concentration, potassium- and water homeostasis and mineralocorticoid receptor (MR) expression level in peripheral leukocytes.

METHODS

We studied 21 renal transplant patients under CsA therapy and 12 healthy controls. Transplant recipients were studied before and under fludrocortisone treatment. Using quantitative reverse-phase polymerase chain reaction (RT-PCR) specific for the MR, we analyzed the level of expression of MR in peripheral leukocytes.

RESULTS

In acidotic transplant recipients (HCO(3) 18.5 +/- 1.2 mM) renal function was only slightly impaired with 2.0 +/- 0.2 mg creatinine/dL when compared with 1.8 +/- 0.3 mg/dL (ns) in non-acidotic patients (HCO(3) 23.0 +/- 2.8 mM). Mean plasma aldosterone levels in renal transplant recipients did not differ from control levels (150 +/- 33 pg/mL vs. 148 +/- 33 pg/mL, ns). In contrast, the expression level of MR in peripheral leukocytes of renal transplant recipients treated with CsA was significantly decreased when compared with healthy controls without renal disease (120 +/- 78 vs. 423 +/- 73 RNA molecules/0.5 microg total RNA, p < 0.01). The level of expression of MR in renal transplant recipients did not differ between acidotic patients and non-acidotic patients (ns). The application of fludrocortisone reversed hyperkalemia and metabolic acidosis without significant effect on MR expression.

CONCLUSIONS

The present data demonstrate that hyperkalemia and metabolic acidosis following CsA treatment in kidney transplantation might be associated with a down-regulation of MR expression on peripheral leukocytes. Electrolyte imbalance is reversible on application of fludrocortisone. This observation supports fludrocortisone treatment in transplant patients with severe electrolyte disturbances.

[Use of maintenance fluid therapy in surgery]

OBJECTIVE

To analyze the use of various maintenance fluid therapy regimens, as well as their adequacy to hospital recommendations, in adult in-patients admitted to a general surgery ward during 1 year.

MATERIAL AND METHODS

Data on solution type and volume, fluid therapy regimen, and duration in days were retrospectively collected for each administered solution from computerized medical orders within the Unit-Dose Drug Distribution Area. A database was developed including the composition of available solutions within our hospital, so that electrolytes, glucose and volumes administered may be calculated.

RESULTS

Out of 354 patients undergoing fluid therapy 125 were selected to receive maintenance regimens. Fluid therapy was administered for more than 5 days in 31% of patients. The most commonly supplied fluids were 5% glucose (43%) and 0.9% saline + 1500 mL of 5% glucose + 60 mEq potassium chloride (CIK). Amongst patients receiving the recommended volume/day (84%) 50% received sodium and potassium more than twice as much the recommended amount, and 70% received glucose amounts not covering minimal daily requirements. Potassium was administered according to recommendations in 85% of patients.

CONCLUSIONS

There is an excessive use of 0.9% saline and 5% glucose to the detriment of 1/3 glucosaline and 10% glucose, which translates as an excessive daily sodium and defective daily glucose provision. In our hospital we have recommended maintenance fluid therapy regimens, as well as fluids more appropriate for postoperative electrolyte replacement; however, their use is still deficient.

Diagnosis and management of electrolyte emergencies

Electrolyte and fluid imbalances are disorders frequently observed in critical care patients. In many instances patients are asymptomatic, but they may also present with neurological alterations, severe muscle weakness, nausea and vomiting or cardiovascular emergencies. Therefore, a pathophysiological understanding of these disorders is necessary for initiating an appropriate therapy. After a precise history-including drug prescriptions-has been obtained from the patient or his/her relatives, determination of the hydration status of the patient and measurement of acid-base status, plasma and urine osmolality and electrolytes are the first steps in the assessment of the disease. Once a diagnosis has been established, great attention has to be paid to the rate at which the disorder is corrected because this-if inappropriate-may cause more severe damage to the patient than the disease itself. This chapter addresses the initial diagnostic and therapeutic steps of the most common electrolyte emergencies.