Effectiveness of Human Atrial Natriuretic Peptide Supplementation in Pulmonary Edema Patients Using the Pulse Contour Cardiac Output System

PURPOSE: Atrial natriuretic peptide (ANP) has a variety of pharmacologic effects, including natriuresis, diuresis, vasodilatation, and suppression of the renin-angiotensin system. A recent study showed that ANP infusion improved hypoxemia and pulmonary hypertension in a lung injury model. On the other hand, the pulse contour cardiac output (PiCCO(TM)) system (Pulsion Medical Systems, Munich, Germany) allows monitoring of the intravascular volume status and may be used to guide volume therapy in severe sepsis and critically ill patients. MATERIALS AND METHODS: We treated 10 pulmonary edema patients without heart disease with human ANP (HANP). The patients were divided into two groups: a group with normal Intrathoracic Blood Volume (ITBV) (900-1100 mL/m2) (n = 6), and a group with abnormal ITBV (n = 4), as measured by the PiCCOtrade mark device; the extravascular lung water (EVLW) and pulmonary vascular permeability index (PVPI) in the two groups were compared. RESULTS: The average patient age was 63.9 +/- 14.4 years. The normal ITBV group showed significant improvement of the EVLW (before, 16.7 +/- 2.7 mL/kg; after, 10.5 +/- 3.6 mL/kg; p = 0.0020) and PVPI (before, 3.2 +/- 0.3; after, 2.1 +/- 0.7; p = 0.0214) after the treatment. The abnormal ITBV group showed no significant improvement of either the EVLW (before, 16.3 +/- 8.9 mL/kg; after, 18.8 +/- 9.6 mL/kg; p = 0.8387) or PVPI (before, 2.3 +/- 0.8; after, 2.7 +/- 1.3; p = 0.2782) after the treatment. In both groups, the EVLW and PVPI were strongly correlated with the chest X-ray findings. CONCLUSION: We conclude that HANP supplementation may improve the EVLW and PVPI in pulmonary edema patients without heart disease with a normal ITBV. The PiCCO(TM) system seems to be a useful device for the management of pulmonary edema.

Biocompatibility of polyvinylalcohol gel as a vitreous substitute.

Polyvinylalcohol (PVA) hydrogel cross-linked by gamma irradiation was assessed as a possible vitreous substitute. From a series of experiments, rise of intraocular pressure and inflammatory changes in the vitreous cavity after operation were observed in some cases. Crab-eating macaques were used for this experiment. PVA gels were injected into vitreous cavity after vitrectomy and followed clinically by opthalmoscopy, tonometry, fundus photography, electroretinogram (ERG), chemotaxis, and flare cell meter. Histopathologic examination by light and electron microscopy was performed after 3 months. As a result, there were no significant changes in ophthalmoscopic findings. No abnormal rising of intraocular pressure (IOP) was recognized. ERG did not show meaningful amplitude weakness. From the photon counting of flare cell meter, significant break of blood-aqueous barrier and blood-retinal barrier was not observed. Histopathologic examination revealed that all layers of the retina were intact and no loss of tissue was evident. However, in PVA gel-injected eyes, some vacuolations of the inner retina were found in some specimens. To conclude, PVA gel was well tolerated in these experiments. The gel with a network similar to the vitreous body showed the best biocompatibility, though it is necessary to investigate the biocompatibility for the long-term. PVA gel is a good candidate for a vitreous substitute.