Severe neonatal Marfan syndrome with a novel mutation in the intron of the FBN1 gene: A case report

RATIONALE

Marfan syndrome (MFS) has been defined as a genetic disorder that affects various systems such as the musculoskeletal, orbital, and cardiovascular systems. Neonatal MFS is considered rare and the most severe form of MFS is characterized by rapidly progressive atrioventricular valve dysfunction, often leading to death during early childhood due to congestive heart failure.

PATIENT CONCERNS

A newborn with neonatal MFS and severe cardiac involvement. He presented various severe clinical features such as arachnodactyly, camptodactyly, elbow and knee joint contracture, senile facial appearance, and deep settling with down-slanting palpebral fissure, hypoplastic ear cartilage, sagging mouth, brachycephaly, and ectopia lentis.

DIAGNOSIS

Genetic analysis revealed a novel mutation at nucleotide 3964 (c.3964 + 1 G > T) in intron 32 of the fibrillin-1 gene. This mutation is identified to be in the so-called neonatal region of fibrillin-1 exon 24 to 32, as reported previously.

INTERVENTIONS

The patient was managed medically for improving the low cardiac output according to severe mitral regurgitation and aortic regurgitation. Afterload reduction, full sedation, and use of diuretic were attempted to improve the oliguria and heart failure.

OUTCOMES

Despite the medical management, aortic regurgitation, mitral regurgitation, pulmonary hypertension, and cardiac contractility got worse. Surgical treatment is essential to prolong the patient's life, however, considerations for the grave progression of the disease make families decide to continue palliative care instead of surgical treatment. A few months after birth, he presented with rapidly progressive aortic regurgitation, mitral regurgitation, and congestive heart failure leading to death.

CONCLUSIONS

This review demonstrated the prominent characteristics of neonatal MFS mutations, it would be helpful for the recognition of novel neonatal MFS variants and valuable for the understanding of the genotype-phenotype correlations and using the plans for managements and counseling in neonatal MFS.

Tolvaptan rescue contrast-induced acute kidney injury: A case report

RATIONALE

Contrast-induced acute kidney injury is one of the most serious adverse effects of contrast media and is related to three distinct but interacting mechanisms: medullary ischemia, formation of reactive oxygen species and direct tubular cell toxicity, especially in the patients with chronic kidney disease. The strategies of treatment, including stabilization of hemodynamic parameters and maintenance of normal fluid and electrolyte balance, were similar to the management of other types of acute kidney injury.

PATIENT CONCERNS

A 58-year-old woman experienced acute oligouria after complex percutaneous coronary intervention for multiple vessel coronary artery disease.

DIAGNOSES

Chest radiography showed pulmonary congestion and hyponatremia was noted after fluid hydration for suspicious contrast-induced nephropathy.

INTERVENTIONS

Oral tolvaptan, at 15mg per day, was used for three days.

OUTCOMES

Urine output increased gradually and symptoms relieved one day later after using tolvaptan. Serum creatinine also improved to baseline level one week later after this event.

LESSONS

Here, we reported an interesting case about contrast-induced acute kidney injury and hypervolemic hyponatremia, where tolvaptan was used to rescue the oliguric phase. Tolvaptan could be considered to use for contrast-induced acute kidney injury and had possibility of prevention from hemodialysis. Larger studies are still needed to investigate the role of tolvaptan in rescuing the oliguric phase in contrast-induced acute kidney injury.

[Low-dose of furosemide to correct oliguria in gynecological surgery]

OBJECTIVE

To investigate the safety and efficay of low-dose furosemide in the correction of oliguria in the patients undergoing gynecologic surgery.

METHODS

A total of 120 patients, aged between 20 to 50 years old, who were scheduled to receive elective gynecological open surgery under general anesthesia, were randomly divided into 3 groups: the control group, furosemide 0. 05 mg/kg (F0.5) group and furosemide 0. 1 mg/kg (F1) group (n=40). During surgery, blood volume and blood pressure was maintained in the normal range. The urine volume was recorded every 30 minutes. Oliguria was defined as the urine volume less than 0. 5 mL/(kg . h), When oliguria was observed, flurosemide or saline was given to the patients based on the enrollment status. If the patients were still oliguric 30 min later, the treatment was repeated. The total time of surgery, net fluid infusion volume, urine volume per unit time per body weight at the completion of surgery, the incidence of intraoperative oliguria, the total amount of furosemide and the average specific gravity of urine were recorded.

RESULTS

There was no statistically significant difference in sex, age, fasting time, the total time of surgery and intraoperative net fluid infusion volume among the three groups (P>0. 05). The urine volume per unit time per body weight in control group was significantly lower than that of the other two groups (P<0. 01). The incidence of intraoperative oliguria in the three groups (control, low dose, high dose groups) were 52. 5%, 12. 5% and 0%, respectively (P<0. 01).

CONCLUSION

Low-dose of furosemide could maintain normal urine volume and specific gravity of urine during gynecological surgery.

[No evidence for renal protective effect of loop diuretics for patients having oliguria]

In many intensive care units, loop diuretics are used more or less routinely to achieve a urinary output above 1 ml/kg/h in critically ill patients. We do not in the literature find any basis of this strategy. In contrast, this practice may cause a risk of circulatory instability in the critically ill patient due to large diuresis and volume depletion. There is no evidence so far that the use of loop diuretics has a renal protective effect or any other beneficial impact on the renal function. The use of loop diuretics in oliguric critically ill patients may be harmful. Consequently an individual assessment is required.

Aminophylline improves urine flow rates but not survival in childhood oliguric/anuric acute kidney injury

INTRODUCTION

Acute kidney injury (AKI) morbidity and mortality rates remain high. Variable AKI outcomes have been reported in association with aminophylline treatment. This study evaluated AKI outcome in a group of Nigerian children treated with aminophylline.

METHODS

This is a retrospective study of AKI in children treated with (N=9) and without (N=8) aminophylline. Studied outcome indices comprised urine flow rate (UFR), duration of oliguria/anuria, progression through AKI stages, number of patients requiring dialysis and mortality.

RESULTS

Mean ages for the control and aminophylline arms were 4.6±2.7 and 4.9±2.1 years (P=0.7), respectively. All patients progressed to stage-3 AKI. Baseline median UFRs in the aminophylline and control arms were similar (0.13 Vs 0.04 ml/kg/hour respectively, P=0.5). The median UFR was significantly higher on day-5 (0.8 Vs 0.1; P=0.03), day-6 (1.0 Vs 0.2; P=0.02), and day-7 (1.2 Vs 0.2; P=0.03) in the aminophylline than the control arm, respectively. Short duration of oliguria/anuria (≤ 6 days) was more frequently observed in aminophylline- treated patients compared to controls (77.8% Vs 25.0%; odds ratio 0.09; 95% CI: 0.01-0.89; P=0.04). Only the aminophylline group maintained steady serum creatinine levels. Four out of five patients in the control group were dialyzed compared to only one out of eight patients in the aminophylline group (odds ratio 0.16; 95% CI: 0.04-0.71; P=0.03). Mortality rates were similar in aminophylline- treated and control patients (33% Vs 25%; hazard ratio 0.8; 95% CI: 0.1-5.5; P=0.8).

CONCLUSION

Aminophylline therapy was beneficial for patients with AKI in terms of improved UFR and reduced need for dialysis, but failed to impact positively on survival.

[Diuretics in pregnancy can do harm]

We describe a case with severe pre-eclampsia with poor obstetric outcome. This patient developed oliguria and received multiple doses of furosemide which probably contributed to the poor outcome. This case presentation reminds of the risks associated with pre-eclampsia in which both blood volume and utero-placental blood flow are already decreased. This condition was further worsened by diuretics.

Use of loop diuretics in the critically ill

Diuretics are commonly used in the intensive care unit, especially for patients with oliguric acute kidney injury. This practice is controversial since there is a lack of evidence regarding any beneficial effects of diuretics either on prevention or treatment of acute kidney injury. Some data even suggest harm when diuretics are used with the goal to influence renal function. However, diuretics can minimize fluid overload, making patient management easier and potentially avoiding many cardiopulmonary and non-cardiopulmonary complications. We will briefly review the available evidence for and against the use of diuretics in the critically ill, including cardiorenal syndromes.

[Blackwater fever in children during cerebral malaria: 3 case reports in Bamako]

BACKGROUND

Blackwater fever is a rare but serious form of malaria in children. Diagnosis relies on clinical symptoms and on the color of the urines.

OBJECTIVES

To describe blackwater fever in children, a disease whose prevalence seems to be increasing.

METHOD

We report 3 cases of blackwater fever observed in our institution.

RESULTS

In 2 cases, acute renal insufficiency with oligoanuria was observed. In all the 3 cases, treatment with quinine was stopped and replaced by injectable artemether. Evolution was dependent on renal function, and included in 1 patient neurological sequels consisting in aphasia.

CONCLUSION

Blackwater fever is a severe affection whose diagnosis should be evoked using the color of urine. Evolution is usually favorable in the pediatric population, when adequate care can be provided.

Continuous low-dose human atrial natriuretic peptide promotes diuresis in oliguric patients after living donor liver transplantation

Human atrial natriuretic peptide (ANP) is beneficial for the prophylaxis of acute renal failure (ARF) after liver transplantation (OLT). We evaluated renal function in OLT patients with or without ARF, describing cases unresponsive to loop diuretics successfully treated with continuous low-dose ANP infusion without hemodialysis. Twenty-seven consecutive adult-to-adult living donor liver transplantations (LDLTs) were performed in 26 patients. One case was excluded due to the need for continuous hemodialysis (HD) during the operation. Of the 26 cases, 6 (23%, group 2) developed ARF in the first 30 days after LDLT; the other 20 were ARF-free (group 1). The median follow-up was 24 months. No patient required either continuous or intermittent HD. Only one patient died due to multiple liver abscesses. Mean preoperative serum creatinine (sCr) value and intraoperative blood loss in group 2 were significantly higher than those in group 1. Three cases in group 2 failed to improve on high-dose loop diuretics with low-dose dopamine, exhibiting fluid overload. The remaining three cases in group 2 responded to conventional diuretic treatments. Continuous low-dose ANP was started 2, 4, or 5 days after LDLT, and urine output significantly increased after ANP administration. The serum creatinine values were 1.1, 1.2, and 1.1 at 1 month and 1.0, 0.9, and 0.6 mg/dL at 6 months after LDLT. Massive blood loss during the operation caused ARF, but did not affect renal function after LDLT. Continuous low-dose ANP improved renal function and diuresis for oliguric ARF patients, preventing the need for HD or continuous venovenous hemodialysis.

Use of fenoldopam to increase urine output in a patient with renal insufficiency secondary to septic shock: A case report

OBJECTIVE

We describe the use of fenoldopam to increase urine output in a pediatric patient with sepsis, heart failure, oliguria, and volume overload.

DESIGN

Case report.

SETTING

A tertiary pediatric intensive care unit.

PATIENT

A 17-year-old male who was being treated for acute lymphoblastic leukemia and was admitted from outside the hospital to the pediatric intensive care unit, in septic shock, after a course of chemotherapy.

INTERVENTIONS

A continuous fenoldopam infusion of 0.03 microg/kg/min was added to a regimen of multiple inotropic and vasopressor agents and a furosemide continuous infusion.

MEASUREMENTS AND MAIN RESULTS

Urine output increased 586% 12 hrs after starting the fenoldopam infusion and 775% from baseline 24 hrs after starting the infusion. Diuretics were decreased while maintaining adequate urine output. No hypotension was noted.

CONCLUSIONS

Fenoldopam increased urine output in a pediatric patient who was in septic shock and oliguria. The mechanism for this effect is unclear, and further trials are necessary to determine the role of fenoldopam in this patient population.

Effect of spironolactone on blood pressure and the renin-angiotensin-aldosterone system in oligo-anuric hemodialysis patients

BACKGROUND

Through its actions on nonepithelial tissues, including brain, blood vessels, and heart, aldosterone may mediate hypertension, cardiac hypertrophy, and fibrosis. Whether aldosterone has a direct pathogenic role in the development of cardiovascular complications in patients with end-stage renal disease is unknown. Oligo-anuric dialysis patients provide a clinical setting to study the effects of the mineralocorticoid receptor blocker spironolactone that are independent of the diuretic properties of the drug. We performed a randomized, double-blinded, placebo-controlled, crossover study to assess the effect of spironolactone on blood pressure and the renin-angiotensin-aldosterone system in oligo-anuric hemodialysis patients.

METHODS

Eight hemodialysis patients were administered either spironolactone, 50 mg, or placebo orally twice daily for 2 weeks, followed by a 3-week washout period, after which patients crossed over in their treatment arms for 2 more weeks.

RESULTS

Administration of spironolactone for 2 weeks decreased predialysis systolic blood pressure from 142.0 +/- 19.6 to 131.4 +/- 18.2 mm Hg (P < 0.05). Compared with placebo, a 2-week course of spironolactone had no effect on predialysis and postdialysis plasma potassium or aldosterone concentrations or renin activity.

CONCLUSION

When administered for 2 weeks, spironolactone, 50 mg twice daily, reduced predialysis systolic blood pressure, but did not produce hyperkalemia in oligo-anuric hemodialysis patients.

Administration of nesiritide in patients after coronary artery bypass surgery induces brisk diuresis

Recombinant human brain natriuretic peptide, nesiritide, has recently been used in limited studies to enhance postoperative diuresis. A retrospective chart review was conducted at a university hospital to assess the efficacy of nesiritide in cardiac surgery patients with fluid overload refractory to diuretics and dopamine. Nine out of 137 patients who underwent coronary artery bypass grafting at the institution from May 2003 to July 2004 exhibited fluid overload despite diuretics and dopamine. Those who did not respond to the therapy, as manifested by oliguria and heart failure, were started on nesiritide. Urine output, weight change, central venous pressure (CVP), pulmonary artery wedge pressure (PAWP), and serum creatinine were the main outcome measures. Within 6 hours after initiation of nesiritide, the average urine output increased from 28 to 130 mL/h. Serum creatinine levels were not significantly different after 24 hours. The mean CVP decreased from 14 to 10 within 12 hours while the PAWP decreased from 24 to 17 mm Hg. Systemic pressures did not change. One patient had to eventually undergo hemodialysis for complications of renal failure. Our experience demonstrates that infusion of nesiritide in patients with heart failure and fluid overload improves diuresis and hemodynamics without major side effects.

Reversal of oliguric tacrolimus nephrotoxicity in children

BACKGROUND

Acute tacrolimus toxicity is manifest by oliguria and elevated serum creatinine. Various vasoregulatory molecules have been implicated in calcineurin inhibitor-mediated nephrotoxicity, including calcium, adenosine and endothelin. Theophylline (THEO), a non-specific adenosine-receptor antagonist prevents renal dysfunction from various nephrotoxins which mediate vasoconstriction. In the setting of acute tacrolimus toxicity, we demonstrated that administration of THEO along with a loop diuretic (LD) enhanced diuresis. This randomized, controlled trial was undertaken to confirm these earlier findings under more rigorous conditions.

METHODS

Children with non-renal visceral transplant(s) and evidence of tacrolimus nephrotoxicity oliguria with a 25% increase in serum creatinine concentration from baseline, a whole blood tacrolimus concentration >20 ng/dl and oliguria resistant to therapy with a LD were randomized to receive either THEO (n = 10) or normal saline placebo (n = 8). Using pre and post (6 h) timed urine collections and coincident plasma concentrations the following were measured or calculated: urine flow rate, net fluid balance, creatinine clearance, fractional excretion of chloride, free water clearance and distal delivery of chloride.

RESULTS

These patients had markedly impaired creatinine clearance at the onset of tacrolimus toxicity. Urine flow increased in the LD + THEO group by 110% over baseline, but was unchanged in the LD + NS group. An increase in creatinine clearance did not reach statistical significance (P = 0.09). Fractional excretion of chloride and distal solute delivery increased after THEO treatment.

CONCLUSIONS

THEO induced a solute diuresis during furosemide-resistant oliguric tacrolimus toxicity in paediatric patients with a trend towards improved renal function.

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.

Use of creatinine clearances to monitor the effect of low-dose dopamine in critically ill surgical patients

INTRODUCTION

Despite uncertain evidence of its efficacy, "low-dose dopamine" (2-5 microg/kg/min) has often been used to augment renal perfusion in critically ill surgical patients. The 2-h creatinine clearance (CC) has been shown to be a monitor of renal function in critically ill patients. We therefore studied the use of sequential CC determinations to monitor the effect of low-dose dopamine (LDD) in surgical intensive care unit (SICU) patients. We hypothesized that sequential CC measurements could demonstrate whether individual patients had positive responses in renal function to LDD.

METHODS

Data were prospectively collected for patients on LDD in a university SICU. CC were recorded for these patients immediately before and after the institution of LDD or before and after the cessation of LDD. APACHE II scores, gender, urine creatinine, age, blood pressure, heart rate, and urine output (UO) were also recorded for these patients; P < 0.05.

RESULTS

Twenty-four pairs of CC values were observed during the study. The mean APACHE II score for the patients was 15.1. In 10 cases after initiation of LDD, the mean CC increased from 52.5 +/- 23.7 ml/min to 68.1 +/- 33.8 ml/min (P = 0.056). UO also increased from 48.0 +/- 27 to 75.9 +/- 49 ml/h (NS). In 14 cases after discontinuation of LDD, CC decreased from 85.6 +/- 36.3 ml/min to 63.6 +/- 45.5 ml/min (P = 0.044) and UO decreased from 105.1 +/- 73.9 to 89.6 +/- 76.7 ml/h (NS). Overall, 13 of the 24 patients had a 25% change or more in CC upon initiation or cessation of LDD.

CONCLUSIONS

LDD institution increased CC in individual patients in the SICU population. Because using LDD in the absence of a discernable improvement in renal function is costly and may harbor risks, we recommend following CC in patients on LDD to determine which patients derive benefit from the intervention.

Bad medicine: low-dose dopamine in the ICU

Low-dose dopamine administration (ie, doses < 5 microg/kg/min) has been advocated for 30 years as therapy in oliguric patients on the basis of its action on dopaminergic renal receptors. Recently, a large, multicenter, randomized, controlled trial has demonstrated that low-dose dopamine administered to critically ill patients who are at risk of renal failure does not confer clinically significant protection from renal dysfunction. In this review, we present the best evidence and summarize the effects of low-dose dopamine infusion in critically ill patients. We review the history and physiology of low-dose dopamine administration and discuss the reasons why dopamine is not clinically effective in the critically ill. In addition to the lack of renal efficacy, we present evidence that low-dose dopamine administration worsens splanchnic oxygenation, impairs GI function, impairs the endocrine and immunologic systems, and blunts ventilatory drive. We conclude that there is no justification for the use of low-dose dopamine administration in the critically ill.

Comparison of the efficacy of continuous furosemide and low-dose dopamine infusion in preeclampsia/eclampsia-related oliguria in the immediate postpartum period

AIM

To compare the efficacy of furosemide infusion with that of low-dose dopamine infusion in improving urine output and subsequent renal function in preeclamptic/eclamptic patients with oliguria in the immediate postpartum period.

DESIGN

Prospective randomised single blind clinical trial.

SETTING

Obstetric High Care Unit of King Edward VIII Hospital, a large referral tertiary hospital.

METHOD

Eighty postpartum patients with severe preeclampsia/eclampsia with oliguria were enrolled. Hypovolaemia was corrected under central venous pressure (CVP) monitoring and urine output monitored for 4 hr. Patients who remained oliguric were randomly assigned to a continuous infusion of low-dose dopamine (3 microg/kg/min), or furosemide 5 mg/hr infusion, for 12 hr. In patients with no response after 12 hr, the drugs were switched and continued for a further 12 hr. A subgroup of patients who responded 4 hr after correction of hypovolaemia was observed for 12 hr. The primary outcome measured involved the comparison in urine output between the different drug regimes and the number of patients requiring haemodialysis. Secondary outcome measures involved assessment of serum urea and creatinine values in the two treatment groups.

RESULTS

Of the 80 patients enrolled, 20 improved their urine outputs within the 4-hr observation period. Sixty patients were randomised to furosemide or low-dose dopamine infusion. There was no statistical significant difference in the mean hourly urine output, rate of change in urine output over time and the mean urea or creatinine levels between the treatment groups. Ten percent of patients that failed on furosemide primarily, and 8.5% of patients that failed on initial low-dose dopamine, received haemodialysis. The difference in demographic and clinic data between these groups was not statistically significant.

CONCLUSION

Administration of continuous infusion of furosemide showed comparable efficacy to low-dose dopamine infusion in ameliorating oliguria in severe preeclampsia/eclampsia post delivery; there was no difference in the percentage of patients that required haemodialysis in either group.

[Dopamine in acute renal failure]

Dopamine is widely used for prevention and treatment of acute renal failure. Its application is based on physiological data suggesting a selective renal effect when it is administrated at a low dose. There is no evidence that dopamine is useful in preventing acute renal failure in patients undergoing high risk procedures. Most of the studies demonstrated lack of benefit from dopamine treatment in cases of acute renal failure. Dopamine has a number of known side-effects. Large randomized controlled trials are required in order to examine outcomes such as mortality, the need for dialysis or the length of hospitalization.

CONCLUSION

The use of dopamine for prevention and treatment of acute renal failure should be avoided.

[Deep hypotension with transient oliguria and severe heart failure in course of acute intentional poisoning with amlodipine]

A case of acute poisoning with amlodipine with deep hypotension, transient oliguria and clinical signs of acute heart failure was described. A woman of 23 years swallowed intentionally 60 tablets of amlodipine (600 mg). After eleven hours of ingestion she was admitted to Warsaw Poison Control Centre. She was in severe clinical condition; tachycardia and deep hypotension were the prominent signs of poisoning. There was not CNS depression. Intensive treatment with i.v. catecholamines (dopamine, norepinephrine), crystalloids (with continuous control of central venous pressure), and i.v. calcium salts (with control of plasma calcium concentration) was started immediately. The patient did not improve but got worse. Acute heart failure developed, especially of left ventricle, so i.v. crystalloids were stopped and dubutamin, morphine, nitroglycerin and glucagon were introduced. Because of oliguria and insufficient effect of high doses of furosemide four-hours hemodiafiltration was set in. The patient's condition slowly improve after third and forth day of hospitalization. The systolic blood pressure rose, heart work was really better and on sixth day--the stabilization of diastolic blood pressure was definitely achieved. The patient was discharge in good condition with heart ejection fraction of 65% measured echocardiographically.

Effect of the selective adenosine A1-receptor antagonist KW-3902 on lipopolysaccharide-induced reductions in urine volume and renal blood flow in anesthetized dogs

We investigated the effects of KW-3902 (8-noradamantan-3-yl-1,3-dipropylxanthine), a potent and selective adenosine A1-receptor antagonist, on lipopolysaccharide (LPS)-induced reduction of urine volume (UV) in anesthetized dogs, in comparison with those of furosemide. LPS was intravenously administered at a dose of 0.5 mg/kg; and the heart rate (HR), systemic blood pressure (BP), renal blood flow (RBF) and UV were measured every 15 min for 4 h. Administration of LPS continuously decreased HR, BP, RBF and UV. KW-3902, furosemide or their corresponding vehicle was given as a bolus injection 5 min after the LPS injection. Treatment with KW-3902 (1 mg/kg, i.v.) ameliorated the LPS-induced decline of UV and RBF. Furosemide (3.2 mg/kg, i.v.) tended to ameliorate the LPS-induced decline of UV but not RBF, the duration of the effect being shorter than that of KW-3902. These results suggest that KW-3902 can ameliorate the oliguria and the decrease in RBF during the early phase of LPS-induced shock. Endogenous adenosine may be involved in the endotoxin-induced oliguria via the adenosine A1-receptor.

Pharmacoeconomic comparison of an albumin-furosemide complex versus sequential therapy for renal insufficiency

The purpose of this economic analysis was to develop an economic model using intra-institutional cost data for acute, oliguric renal insufficiency treated with either an albumin-furosemide complex or albumin followed by furosemide (sequential therapy). The perspective of this study was from the standpoint of the institution (University Medical Center, a teaching hospital). The decision tree and sensitivity analyses demonstrated that the albumin-furosemide complex would be more effective and less costly than sequential therapy for a range of outcome probabilities. Using effectiveness assumptions from published literature, the complex could avoid dialysis in 27% of patients compared with 8% of patients receiving sequential therapy. The complex would also be less costly ($7778 vs $8748). In terms of cost-effectiveness, the complex is $28,807 per averted dialysis compared with $109,350 for sequential therapy.

Low-dose theophylline increases urine output in diuretic-dependent critically ill children

OBJECTIVE

Determine the effect of low-dose theophylline on urine output and the urinary adenosine: cAMP (cyclic adenosine monophosphate) excretion ratio (a measure of phosphodiesterase inhibition) in diuretic-dependent critically ill children.

DESIGN

Observational clinical case series and animal laboratory experiment.

SETTING

A university pediatric intensive care unit and a pharmacology research laboratory.

PATIENTS

10 consecutive oliguric patients treated with theophylline for diuresis.

INTERVENTIONS

Urine output, fluid intake, diuretic dosages, and number of pressors (including dopamine) were monitored over the 24-h period prior to and the 24-h period immediately after theophylline was started. Hourly collections of urine were obtained at baseline and 1 and 3 h after theophylline was started and urinary excretion rates of adenosine and cAMP were measured and calculated.

MEASUREMENTS AND RESULTS

Mean theophylline level in the children was 5.0 microg/ml. Urine output increased from 1.58 +/- 0.46 to 3.75 +/- 0.77 ml/kg per h (p = 0.008, paired t-test) after theophylline administration. There was no significant change in fluid intake, vasoactive agents, or dosages of other diuretics during the study periods. Intrarenal infusion of the IC50 concentration of isobutylmethylxanthine for phosphodiesterase activity resulted in a reduction of the adenosine: cAMP urinary excretion ratio in rats (p < 0.05). Low-dose theophylline had no effect on the adenosine: cAMP urinary excretion ratio in children. Concurrent therapy with dopamine was associated with an enhanced diuretic effect of theophylline (with dopamine, 1.30 +/- 0.30 to 5.07 +/- 0.77 ml/kg per h vs without dopamine, 1.77 +/- 0.76 to 2.86 +/- 1.08 ml/kg per h; p = 0.03, two-way ANOVA). There was no interaction between dopamine and low-dose theophylline on the urinary adenosine: cAMP excretion ratio (p = 0.56, two-way ANOVA).

CONCLUSIONS

Theophylline increased urine output in diuretic-dependent critically ill children and the diuretic effect may have been potentiated by concurrent use of dopamine. Adenosine receptor antagonism may be a more likely mechanism for the diuretic effect of theophylline than phosphodiesterase inhibition.

Effects of low-dose dopamine on urine output in oliguric, critically ill, renal transplant patients

Low-dose dopamine (LD-DA) has been used extensively to increase urine output (UO) in critically ill patients. These effects have recently been documented in patients with normal and mildly abnormal renal function. The purpose of this study was to quantitate the effects of LD-DA on UO and urineNa (UNa) excretion in renal transplant (RT) patients, and thereby evaluate the effects of LD-DA on the denervated kidney.

METHODS

Five RT patients and 7 non-transplant controls, hospitalized in the surgical intensive care unit (SICU), with serum creatinine (serum Cr) < 2 mg/dL who were oliguric (UO < 0.5 mL/kg/h), received LD-DA (2.5 micrograms/kg/min). None received other diuretics within 12 h, and all had pulmonary artery occlusion pressure (PAOP) > 10 mmHg and CI > 3.0 L/min/m2. UO was measured hourly and averaged for 2 h pre and 6 h during LD-DA. All data are mean +/- SD.

RESULTS

APACHE II (14 +/- 4), CI (4.1 +/- 1.2 L/min/m2), PAOP (15 +/- 4 mmHg), HR (98 +/- 16/min), and MAP (83 +/- 10 mmHg) were similar between groups and did not change during LD-DA therapy. Initial serum Cr in the RT group (1.6 +/- 0.4 mg/dL) was greater than that in controls (0.9 +/- 0.24 mg/dL), p < 0.05. Initial UO [0.26 +/- 0.10 mL/kg/h (RT) and 0.31 +/- 0.12 mL/kg/h (controls)] and initial UNa [8 +/- 62 meq/L (RT) and 54 +/- 28 meq/L (controls)] were not different. Urine output increased significantly compared with baseline in both groups [final UO 0.55 +/- 0.14 mL/kg/h (RT) and 0.96 +/- 0.41 mL/kg/h (controls)]. Final UNa [72 +/- 37 meq/L (RT) and 99 +/- 56 meq/L (controls)] were not different from each other or from baseline.

CONCLUSIONS

LD-DA increases UO, but not UNa excretion, in RT patients with oliguria, comparably to controls. These data suggest that this effect is predominantly mediated by dopaminergic receptors, since the transplanted kidney is denervated and there were no significant associated changes in hemodynamic parameters during the study.

Efficacy of urate oxidase (uricozyme) in tumour lysis induced urate nephropathy

Urate oxidase (uricozyme) is an enzyme of non-human origin capable of oxidizing human uric acid to allantoin, a highly soluble product at renal tubule pH. We report its efficacy in three patients with acute urate nephropathy due to tumour lysis in chronic lymphatic leukaemia and high grade lymphoma. Two patients had an additional obstructive nephropathy due to ureteric urate crystals. An intravenous infusion (100 units/kg in 50 ml saline over 30 min) was given for between two and five consecutive days. All patients showed a rapid fall in serum urate levels with associated diuresis, correction of metabolic disturbance and full resolution of uraemia within a week. The treatment was well tolerated and caused a rapid resolution of clinical symptoms in all cases. We review the literature relating to the use of this agent both in the treatment of hyperuricaemic acute renal failure and gouty arthritis.

Low dose dopamine in postpartum pre-eclamptic women with oliguria: a double-blind, placebo controlled, randomised trial

OBJECTIVE

To assess the effect of low dose dopamine on the urine output in postpartum pre-eclamptic or eclamptic women with oliguria.

DESIGN

A double blind, randomised controlled study.

SETTING

The high care area of the labour ward in a teaching hospital.

SAMPLE

Forty postpartum pre-eclamptic women with oliguria, defined as < 30 mL/hour, who have not responded to a 300 mL crystalloid fluid challenge.

INTERVENTION

Dopamine was infused at a rate of 1 to 5 microg/kg per minute, or sterile water was given as placebo in the same dilution.

MAIN OUTCOME MEASURE

Urine output, blood pressure and pulse was measured for six hours before and for six hours after the intervention.

RESULTS

Women who received dopamine (344 mL over 6 hours) showed a clinically and statistically significant (P = 0.0014, Mann-Whitney U test) higher median urine output compared with those receiving placebo (135 mL over 6 hours) for the duration of therapy. The respective 95% confidence intervals were 212.3 to 712.7 mL compared with 73.8 to 244.7 mL. No differences in blood pressure or pulse were found between the two groups.

CONCLUSIONS

The use of low dose dopamine in a labour setting improved urine output in postpartum pre-eclamptic women with oliguria who had not responded to a single fluid challenge without a detrimental effect on the blood pressure or pulse.

Single needle venovenous extracorporeal membrane oxygenation using a nonocclusive roller pump for rescue in infants and children

In 1993, J.Y. Chevalier described a single needle venovenous extracorporeal membrane oxygenation (ECMO) system using a nonocclusive roller pump and alternating clamps for pulmonary support in neonates. We modified this system to use it in older children as well and for additional indications. Introducing a double raceway and 2 different sizes of tubing sets and performing percutaneous approach, we treated 21 children (age 1 day to 49 months) using this system. Indications for treatment were hypoxia and hypoxic induced myocardial dysfunction resulting from pulmonary failure, sepsis, and congenital defects. Of the children treated for neonatal indications, 7/9 survived. For 2 children ECMO was terminated because of intraventricular hemorrhage (IVH). In the pediatric group 5/7 of the children could be weaned from ECMO, and 2 children died after more than 30 days on ECMO. Two of the children who had been almost completely weaned died later because of therapy withdrawal following a brain death diagnosis. In the cardiac group, 3/5 of the children survived. We conclude that the described system is an effective venovenous ECMO system that reduces invasivity and expenditure.

Tumescent liposuction complicated by pulmonary edema

In tumescent liposuction, large volumes of dilute lidocaine and epinephrine are infused subcutaneously to prepare fat for extraction. Reported cardiopulmonary complications of tumescent liposuction have been few, and the anesthetic and hemodynamic advantages are several. We report an instance of pulmonary edema in a healthy 55-year-old male body-builder who received 7900 cc subcutaneous and 2200 cc intravenous fluid. With normal cardiopulmonary and renal function, the patient responded promptly to intravenous diuretics without sequelae. Out of over 900 patients who have had tumescent liposuction with up to 15 liters infused parenterally, this is the first case of pulmonary edema.

Circulatory and diuretic effects of dopexamine infusion in low-birth-weight infants with respiratory failure

OBJECTIVE

To investigate the effects of infusion of dopexamine hydrochloride, a new synthetic catecholamine, on cardiopulmonary status and urine output in neonates with respiratory and circulatory failure.

DESIGN

Prospective clinical study with each patient serving as his own control.

SETTING

Intensive care unit (14 beds) in a 300-bed paediatric teaching hospital.

PATIENTS

Seventeen neonates with low birth weight (LBW) requiring mechanical ventilation in the first 4 days of life, who initially had two of the following symptoms: hypotension, oliguria, metabolic acidosis with base deficit >10 and failure to respond to volume loading.

INTERVENTIONS

Cardiopulmonary variables, diuresis and acid-base status were measured before and after volume loading, in patients who did not improve infusion of dopexamine was started at a dose of 2 microg kg-1 min-1 which was titrated to achieve blood pressure, urine output, and base deficit in normal range. Observations were continued for a period of 5 h.

MEASUREMENTS AND RESULTS

Systolic blood pressure increased significantly after 3 h. of dopexamine infusion and remained elevated up to the end of the study period. Diastolic and mean blood pressure increased slightly (NS). Diuresis increased significantly from the 4th h of dopexamine infusion. Arterial blood pH increased significantly from baseline at 5 h after the start of dopexamine administration. There was also a significant improvement in the PtcO2/PaO2 index.

CONCLUSION

In neonates with respiratory and circulatory failure, dopexamine increases blood pressure and improves arterial pH and urine output.

High-dose intravenous melphalan in a patient with multiple myeloma and oliguric renal failure

A kappa light-chain myeloma was diagnosed as the underlying disease in a 52-year-old woman with acute oliguric renal failure. The patient was erroneously treated with high-dose intravenous melphalan (60 mg/m2). Because of this overdose treatment with granulocyte colony-stimulating factor was initiated, but pronounced absolute leukopenia (white blood cell count < 0.5 x 10(9)/l) developed and lasted for 13 days. Following melphalan treatment a continuous increase in urine volume was accompanied by a decrease of serum creatinine and blood urea nitrogen. Within 10 days after the administration of melphalan the patient no longer required hemodialysis. We conclude that high-dose chemotherapy in combination with hematopoietic growth factors should be considered in individual cases with newly diagnosed light-chain nephropathy.

Haemodynamic, renal and hormonal responses to enalkiren in four patients with post-surgical oliguria

1. The haemodynamic and hormonal responses of four patients with acute post-surgical oliguria (urine output < 0.5 mL/kg per h) were measured in response to the renin inhibitor enalkiren. Enalkiren was infused at 0.01 up to 0.1 mg/kg per h for up to 4 h. 2. Enalkiren infusion was associated with a progressive fall in blood pressure, clinically significant in three of the four patients. Systemic vascular resistance fell in proportion to blood pressure fall. Cardiac output and pulse rate remained unchanged. Effective renal plasma flow rose in all four cases (236 +/- 19 to 327 +/- 38). There was no change in urine flow rate, or urinary sodium excretion. 3. Plasma renin activity (ng angiotensin I/mL per h) fell from 1.9 +/- 0.5 to 0.02 +/- 0.01 (P < 0.04), plasma angiotensin II (pg/mL) fell from 104 +/- 93 to 7.7 +/- 1.5, and plasma aldosterone (ng/dL) fell from 32 +/- 8 to 21 +/- 9 (P = 0.03) at the highest infusion dose. 4. Enalkiren inhibited plasma renin activity with reduced plasma angiotensin II and aldosterone concentrations. This was associated with vasodilation, reduced blood pressure and maintained cardiac output. There was no beneficial effect on renal function in these patients with post-surgical oliguria.

Quantitative effects of low-dose dopamine on urine output in oliguric surgical intensive care unit patients

OBJECTIVE

To quantify the magnitude and time course of the effect of low-dose dopamine (2.5 micrograms/kg/min) infusions on urine output in oliguric patients.

DESIGN

A prospective, clinical study.

SETTING

A surgical intensive care unit (ICU) at a university hospital.

PATIENTS

A total of 19 surgical ICU patients with oliguria (< 0.5 mL/kg/hr) after resuscitation to pulmonary artery occlusion pressures > 10 mm Hg, mean arterial pressures > 65 mm Hg, and cardiac index > 2 L/min/m2. Patients with acute renal failure and those patients receiving diuretics were excluded.

MEASUREMENTS AND MAIN RESULTS

Urine output was monitored hourly before and after dopamine was instituted for the treatment of oliguria. Spot urine electrolyte determinations and urine specific gravity measurements were obtained. Patients with urine output improvement (> 50% increase) had dopamine stopped after 4 hrs. If urine output decreased to < 0.5 mL/kg/hr, dopamine was resumed. There were no dopamine-induced changes in heart rate, pulmonary artery occlusion pressure, mean arterial pressure, or cardiac index. Mean urine output increased from 0.29 to 1.04 mL/kg/hr (p < .001) while patients were receiving dopamine. Time-to-peak response to dopamine was 7 hrs. Urine output increased to > 0.5 mL/kg/hr in 95% of patients, doubled in 89% of patients, and exceeded 1.0 mL/kg/hr in 84% of patients. After dopamine was stopped, urine output decreased to < 0.5 mL/kg/hr in 79% of patients and responded to resumption of dopamine in 100% of patients. There were no significant changes in urine sodium concentration or specific gravity.

CONCLUSIONS

Low-dose dopamine infusion alone produces a drug-dependent increase in urine output in oliguric, euvolemic ICU patients. Maximal effect is temporally variable.

Effects of low-dose dopamine infusion on cardiovascular and renal functions, cerebral blood flow, and plasma catecholamine levels in sick preterm neonates

Effects of 2 and 4 micrograms/kg/min dopamine infusion on cardiovascular and renal functions, cerebral blood flow (CBF) and plasma catecholamine levels were studied in sick preterm neonates during the first four days of life. Preterm infants were found to have an enhanced responsiveness to the pressor effects of dopamine during this period. Comparison of the renal effects of 2 and 4 micrograms/kg/min dopamine in 61 preterm infants indicate that 2 micrograms/kg/min dopamine induces maximum diuresis and natriuresis during the first day of life provided that systemic blood pressure is within the predicted normal range. Although administration of 4 micrograms/kg/min dopamine induces further increases in blood pressure and glomerular filtration rate, urine output and sodium excretion remain similar to that on 2 micrograms/kg/min of the drug. These findings demonstrate that the direct tubular effects of dopamine play an important role in the diuretic and natriuretic action of the drug in the one-day old preterm infant. In five preterm neonates, changes in CBF transiently paralleled the dopamine-induced alterations in systemic blood pressure indicating that autoregulation of CBF is impaired but not completely ineffective in the one-day old preterm infant. In eight term neonates, increases in blood pressure had no effect on CBF. Measurements of plasma dopamine and norepinephrine levels in 14 preterm neonates and five children suggest that decreased metabolism of dopamine may contribute to the enhanced pressor responsiveness to dopamine in sick preterm infants.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of thromboxane A2 receptor blockade on oliguric ischemic acute renal failure in conscious rats

To investigate the potential pathogenetic and therapeutic roles of thromboxane A2 (TXA2) and its receptor blockade, respectively, in the early phase of ischemic acute renal failure (ARF), renal function, TXB2 excretion, and the effects of the specific TXA2 receptor antagonist sulotroban (SU) in a model of unilateral renal artery occlusion in conscious female Sprague-Dawley rats were studied. Occlusion of the left renal artery for 1 h in untreated (i.e., vehicle-treated) rats (N = 8) resulted in oliguric ARF. In SU-treated rats (N = 8), the drug was given as an i.v. bolus of 5 mg/kg body wt, followed by a continuous infusion of 0.5 mg/min.kg body wt from 1 h before and during ischemia and for 6 h after reflow. After 1 h of ischemia, urine volume of left ischemic kidneys from untreated rats had decreased from 13.2 +/- 2.8 to 1.0 +/- 0.3 and 0.5 +/- 0.2 microL/min.100 g at 2 and 6 h of reflow, respectively, and GFR had decreased from 0.32 +/- 0.04 mL/min.100 g body wt to undetectable values. At 6 h of reflow, medullary Na-K-ATPase was slightly (P < 0.05) reduced in left ischemic kidneys, whereas medullary and papillary enzyme activities were compensatorily increased (P < 0.01) in right intact kidneys. The ADP/O ratio of cortical mitochondria was 41% (P < 0.05) and ATP synthesis was 77% (P < 0.01) lower than in right intact kidneys.(ABSTRACT TRUNCATED AT 250 WORDS)

Low-dose dopamine in critically ill oliguric patients: the influence of the renin-angiotensin system

OBJECTIVE

To assess the effect of low-dose dopamine on urine output and natriuresis in critically ill oliguric patients and the relationship of this response to the renin-angiotensin aldosterone system.

DESIGN

A prospective, controlled study.

SETTING

A multidisciplinary intensive care unit of a teaching hospital.

SUBJECTS

Critically ill, volume-resuscitated, oliguric patients.

INTERVENTION

Dopamine was infused at a rate of 2 micrograms/kg/min. The change in urine output and sodium excretion was measured over a 6-hour period. Plasma Renin Activity (PRA) and serum aldosterone were measured before commencing low-dose dopamine.

OUTCOME MEASURE

Patients whose mean urine output increased by greater than 20 ml/hour were considered to have responded to low-dose dopamine.

RESULTS

Nine patients were studied. Five of the nine patients responded to low-dose dopamine. The mean increase in urine volume was 58.4 ml/hr in the responders compared with 5.0 ml/hr in the nonresponders. The mean PRA (normal, 0.8 to 2.5 ng/ml/hr) was 5.7 ng/ml/hr in the responders compared with 26.8 ng/ml/hr in the nonresponders (p = 0.042). A significant inverse correlation existed between the PRA and the increase in urinary output (r = -0.75; p = 0.019).

CONCLUSION

The response to renal dopamine in critically ill patients appears to be dependent on the interaction between the vasodilating-natriuretic effect of dopamine and the vasoconstricting antinatriuretic effect of the renin-angiotensin aldosterone system.

Enhancement of urine output and glomerular filtration in acutely oliguric patients using low-dose norepinephrine

A prospective clinical trial was initiated to test the hypothesis that low-dose norepinephrine enhances urine output and renal function in oliguric surgical patients. Norepinephrine (0.05 or 0.1 micrograms/kg/min) was infused into nine oliguric (< or = 0.5 ml/kg/hr), volume-replete, hemodynamically stable patients. There was an average increase of urine output of 13 ml/hr (48% over baseline) and an increase of 31.7 ml/min (47% over baseline) in creatinine clearance. Both these results were statistically significant. Mean arterial pressure was the only hemodynamic parameter that changed significantly, rising an average of 12 mm Hg. We conclude that low-dose norepinephrine infusion may enhance renal function and urine output in acutely oliguric surgical patients who have been appropriately fluid resuscitated.

Low-dose dopamine induces early recovery of recombinant interleukin-2--impaired renal function

Recombinant interleukin-2 (rIL-2) can produce impairment of renal function with hypotension, fluid retention, elevated blood urea nitrogen, oliguria and low fractional sodium excretion; these side-effects are a common cause of reduction or interruption of rIL-2 infusion. The aim of this study was to investigate the control and treatment of renal toxicity induced by rIL-2 therapy. Here we show that dopamine, at a low dose of 2 micrograms/kg/min, completely prevented renal toxicity induced by rIL-2. While continuing rIL-2 therapy, 24-h continuous infusion of low-dose dopamine produced a rapid normalisation of urine output and a significant decrease in serum creatinine levels and body weight (P < 0.01), with an early and complete recovery of the rIL-2--impaired renal function: mean recovery time of renal function in patients treated with dopamine was significantly lower (P < 0.05) than in nontreated patients (4.8 days vs. 10 days, respectively).

Dopamine treatment for severe ovarian hyperstimulation syndrome

Seven oliguric patients with severe ovarian hyperstimulation syndrome following gonadotrophin treatment for in-vitro fertilization or gamete intra-Fallopian transfer, were treated with low doses of dopamine by peripheral infusion. Five patients were pregnant. The rationale for this therapeutic approach was to increase renal blood flow and glomerular filtration. In addition to dopamine, fluid intake was restricted to 500 ml/day and a protein and salt-rich diet was provided in order to increase serum osmolarity. Within 24-48 h from the beginning of the dopamine treatment, the syndrome started to regress in all cases. No adverse maternal or fetal effects occurred. We conclude that dopamine therapy may constitute a major advance towards the management of severe ovarian hyperstimulation syndrome.

Prospective, double-blind, concurrent, placebo-controlled clinical trial of intravenous ribavirin therapy of hemorrhagic fever with renal syndrome

A prospective, randomized, double-blind, concurrent, placebo-controlled clinical trial of intravenous ribavirin (loading dose of 33 mg/kg, 16 mg/kg every 6 h for 4 days, and 8 mg/kg every 8 h for 3 days) was conducted in 242 patients with serologically confirmed hemorrhagic fever with renal syndrome (HFRS) in the People's Republic of China. Mortality was significantly reduced (sevenfold decrease in risk) among ribavirin-treated patients, when comparisons were adjusted for baseline risk estimators of mortality (P = .01; two-tailed). HFRS typically consists of five consecutive but frequently overlapping clinical phases. Only occurrence of oliguric phase and hemorrhage was associated with severity of clinical disease in the placebo group. Ribavirin therapy also resulted in a significant reduction in the risk of entering the oliguric phase and experiencing hemorrhage. The only ribavirin-related side effect was a well-recognized, fully reversible anemia after completion of therapy.

Combined ascitic--fluid and furosemide infusion: a therapeutic option for massive diuretic-resistant ascites and severe oliguria of hepatic cirrhosis

We describe the successful use of combined ascitic-fluid and furosemide infusion as a therapeutic option in the management of massive diuretic-resistant ascites and severe oliguria of hepatic cirrhosis in a 30-year-old Nigerian male farmer. It is simple, safe, convenient and effective treatment modality. The mechanics of this procedure seen against the backgroup of the pathogenesis of sodium retention and renal dysfunction in hepatic cirrhosis is discussed.

Intrathecal morphine analgesia and low-dose dopamine for oliguria in severe maternal pulmonary hypertension. A case report

Maternal pulmonary hypertension can be life threatening, and many problems and complications can occur during labor and delivery as well as postpartum. A case of severe maternal pulmonary hypertension was monitored with a pulmonary artery catheter. Intrathecal morphine was administered for labor analgesia, and low-dose dopamine was utilized for maternal oliguria. Neither the morphine nor the dopamine resulted in adverse maternal hemodynamic effects. Both analgesia and resolution of the oliguria were accomplished.

Low dose dopamine in the treatment of persistent oliguria in pre-eclampsia

Oliguria in pre-eclamptic women is most often a result of decreased intravascular volume. In a small number of patients, renal vascular spasm may be the cause of decreased urine output. Prolonged oliguria/anuria secondary to vasospasm may lead to permanent renal damage. When volume repletion is unsuccessful in restoring urine output, some authors have suggested the use of peripheral vasodilators such as hydralazine. Dopamine in low doses 2 micrograms/kg per min was used successfully to restore urine output within an hour in a pre-eclamptic patient who had been essentially anuric for 8 h. Volume administration and hydralazine were unsuccessful. In the rare instance of a patient who is unresponsive to conventional methods, low dose dopamine may provide an adjunctive therapy to restore urine output after delivery. Central monitoring is essential in following such patients.

Acute renal failure of leptospirosis: nonoliguric and hypokalemic forms

Acute renal failure induced by leptospirosis was studied in 56 patients. A higher frequency of nonoliguric renal failure was observed with lower morbidity and mortality rates than in oliguric forms. In addition, 45% of the patients in this series were hypokalemic, and no hyperkalemic patients were seen. A prospective study in 11 patients showed an initially elevated urinary fractional potassium excretion that fell simultaneously with the high urinary fractional sodium excretion and the urinary K/Na ratio, suggesting an increased distal potassium secretion due to an increased distal sodium delivery consequent to functional impairment of the proximal reabsorption of sodium.

Dopexamine hydrochloride, a novel drug with renal vasodilator properties: two case studies

Two patients who received an infusion of dopexamine hydrochloride are presented. The dopexamine infusion was associated with a useful increase in urine output. The mechanisms for these effects are discussed and the renovascular dilatation associated with dopexamine highlighted.