Israel Medical Association Journal

Reversible cerebral vasoconstriction syndrome (RCVS) comprises a group of conditions characterized by reversible vasoconstrictions of cerebral arteries. Clinical manifestations include sudden-onset severe headaches with or without additional neurologic signs and symptoms [1].

The incidence of RCVS is 2.7 cases per million adults. It predominantly affects women, and about 9% of all RCVS cases occur during the postpartum period [2,3]. Other possible precipitating factors, such as subarachnoid hemorrhage, ischemic stroke, intracranial hemorrhage, and exposure to vasoactive drugs, have also been reported in association with RCVS [2]. The exact pathophysiology of RCVS is not well understood, although hormonal influences have been suggested as possible contributing factors.

Alkalosis-induced cerebral vasoconstriction is described but not well understood. Hyperventilation is commonly used in neurologic patients to decrease intracranial pressure and cerebral blood flow. Hyperventilation causes cerebral vasoconstriction directly by hypocapnia and may indirectly affect through alkalosis.

We present a case of RCVS in a postpartum patient admitted to the intensive care unit (ICU) with severe metabolic alkalosis necessitating hemodialysis.

Among patients admitted with acute decompensated heart failure (ADHF), deterioration of renal function with resulting acute kidney injury (AKI) is reported in up to 70% of patients with cardiogenic shock. Twenty percent of heart failure patients with AKI progress to dialysis (AKI-D). Optimal timing for initiation of renal replacement therapies (RRT) has been researched; however, minimal studies discuss guidelines for weaning from RRT [1]. Electronic monitoring of urine output (UO) may serve as a tool to aid in withdrawal from RRT. We present a case of ADHF with severe AKI requiring continuous renal replacement therapy (CRRT) where real-time electronic monitoring of UO was implemented for the first time to guide de-escalation therapy from CRRT until successful withdrawal.

Carbamoyl phosphate synthetase 1 (CPS1; MIM *608307; E.C. 6.3.4.16) is the first rate-limiting enzyme of the urea cycle, an essential metabolic pathway for ammonia detoxification. CPS1 deficiency (CPS1-D) is characterized by severe hyperammonemia during disease exacerbations. During a metabolic crisis, children with CPS1-D are admitted with vomiting, altered mental status, and high serum levels of ammonia. Rapid normalization of ammonia level ameliorates neurological outcome [1,2]. The first-line treatment for hyperammonemia in these patients is ammonia scavengers in combination with citrulline or arginine and high-calorie supplementation while controlling protein intake [1].

Background: The role of continuous renal replacement therapy in patients with acute renal failure is well recognized. CRRT[1] has also become an important modality of treatment in various acute situations without renal failure.

Objectives: To describe our experience with CRRT in acutely ill infants and children without renal failure.

Methods: We analyzed all infants and children who underwent CRRT during the years 1998-2000 in the pediatric intensive care unit and we focus our report on those who were treated for non-renal indications.

Results: Fourteen children underwent 16 sessions of CRRT. The indications for CRRT were non-renal in 7 patients (age range 8 days to 16 years, median = 6.5). Three children were comatose from maple syrup urine disease, three were in intractable circulatory failure secondary to septic shock or systemic inflammatory response, and one had sepsis with persistent lactic acidosis and hypernatremia. Three children underwent continuous hemodiafiltration and four had continuous hemofiltration. The mean length of the procedure was 35 ± 24 hours. All patients responded to treatment within a short period (2–4 hours). No significant complications were observed. Two patients experienced mild hypothermia (34°C), one had transient hypotension and one had an occlusion of the cannula requiring replacement.

Conclusion: Our findings suggest that CRRT is a safe and simple procedure with a potential major therapeutic value for treating acute non-renal diseases in the intensive care setting.