Syndromes related to sodium and arginine vasopressin alterations in post-operative neurosurgery.

BACKGROUND: Cerebral salt wasting syndrome (CSWS), syndrome of inappropriate antidiuretic hormone secretion (SIADH) and diabetes insipidus (DI) are frequently found in postoperative neurosurgery. PURPOSE: To identify these syndromes following neurosurgery. METHOD: The study included 30 patients who had been submitted to tumor resection and cerebral aneurysm clipping. Sodium levels in serum and urine and urine volume were measured daily up to the 5th day following surgery. Plasma arginine vasopressin (AVP) was measured on the first, third and fifth days post-surgery. RESULTS: CSWS was found in 27/30 patients (90%), in 14 (46.7%) of whom it was associated with a reduction in the levels of plasma AVP (mix syndrome). SIADH was found in 3/30 patients (10%). There was no difference between the two groups of patients. CONCLUSION: CSWS was the most common syndrome found, and in half the cases it was associated with DI. SIADH was the least frequent syndrome found.

Syndromes related to sodium and arginine vasopressin alterations in post-operative neurosurgery

BACKGROUND: Cerebral salt wasting syndrome (CSWS), syndrome of inappropriate antidiuretic hormone secretion (SIADH) and diabetes insipidus (DI) are frequently found in postoperative neurosurgery. PURPOSE: To identify these syndromes following neurosurgery. METHOD: The study included 30 patients who had been submitted to tumor resection and cerebral aneurysm clipping. Sodium levels in serum and urine and urine volume were measured daily up to the 5th day following surgery. Plasma arginine vasopressin (AVP) was measured on the first, third and fifth days post-surgery. RESULTS: CSWS was found in 27/30 patients (90 percent), in 14 (46.7 percent) of whom it was associated with a reduction in the levels of plasma AVP (mix syndrome). SIADH was found in 3/30 patients (10 percent). There was no difference between the two groups of patients. CONCLUSION: CSWS was the most common syndrome found, and in half the cases it was associated with DI. SIADH was the least frequent syndrome found.

INTRODUÇÃO: A síndrome perdedora de sal (SPS), síndrome da secreção inapropriada do hormônio antidiurético (SIADH) e diabetes insipidus (DI) são freqüentemente encontradas no pós-operatório de neurocirurgia. OBJETIVO: Identificar essas síndromes relacionadas à neurocirurgia. MÉTODO: Foram estudados 30 pacientes submetidos à ressecção de tumor (n=19) e clipagem de aneurisma (n=11) cerebral durante os primeiros cinco dias do pós-operatório. Os pacientes foram submetidos a dosagens diárias de sódio sérico e urinário até o 5° dia pós-operatório, com controle de volume urinário neste período e dosagem de arginina-vasopressina (AVP) plasmática no 1°, 3° e 5° dias pós-operatórios. RESULTADOS: A SPS foi encontrada em 27/30 pacientes (90 por cento), em 14/27 (46,7 por cento) associada à diminuição dos níveis de AVP plasmática (síndrome mista). A SIADH foi encontrada em 3/30 pacientes (10 por cento). Não houve diferença entre os dois grupos de pacientes. CONCLUSÃO: A SPS foi a síndrome mais freqüente, em metade de casos associada ao DI. A SIADH foi a menos freqüente.

In vivo effects of the controlled NO donor/scavenger ruthenium cyclam complexes on blood pressure.

Ruthenium(II/III) complexes able to bind and release NO* were tested in vivo, in conscious Wistar rats instrumented for continuous blood pressure (BP) measurement and administration of in bolus injections (5 to 100 nmol/Kg i.v.) of trans-[Ru(II)Cl(NO+)(cyclam)](PF6)2 (cyclam-NO) or sodium nitroprusside (SNP). For normotensive rats, cyclam-NO produced a sustained 10% BP reduction of basal MAP during 7 +/- 0.4 to 11 +/- 0.3 min. In acute hypertensive rats, cyclam-NO produced BP reduction 3-fold larger than in normotensive rats and similar to that of SNP (maximal effect: 41 +/- 1.3 vs. 45 +/- 2.2 mmHg, respectively). However, the duration of the effect of cyclam-NO was 13 to 21-fold longer than that of SNP. The hypotensive effect of cyclam-NO was fully blocked in presence of continuous infusion of a NO* scavenger, carboxy-PTIO (6 mmol/Kg/min), or of the inhibitor of cGMP activation, methylene blue (83 nmol/Kg/min), or of the cyclam-NO precursor, trans-[RuCl(tfins)(cyclam)](tfms) (cyclam-tfms) (500 mmol/Kg/min). The long lasting BP reduction of cyclam-NO can be interpreted in terms of a slower rate of NO* release (k-NO = 2.2 x 10(-3) S(-1) at 35 degrees C) following chemical reduction (E(0') = 0.10 V vs NHE). In summary, cyclam-NO showed an hypotensive effect around 20 times longer than SNP in either normotensive or hypertensive rats, which was completely inhibited by methylene blue or carboxy-PTIO. Continuous infusion of cyclam-tfms completely blocked the hypotensive effect of cyclam-NO by scavenging the NO* released by the reduced cyclam-NO.