Atrial and brain natriuretic peptide changes in an experimental model of intra-abdominal hypertension.

BACKGROUND: Intra-abdominal hypertension (IAH) can have a profound impact on the cardiovascular system. We hypothesized that natriuretic peptides (Nt-pro-ANP and Nt-pro-BNP) are produced in response to the cardiovascular changes observed in an experimental model of IAH. MATERIALS AND METHODS: Eleven female pigs were enrolled in this study. Four experimental phases were created: a baseline phase for instrumentation (T1); two subsequent phases (T2 and T3), in which helium pneumoperitoneum was established at 20 and 35 mm Hg, respectively; and the final phase (T4), in which abdominal desufflation took place. Hemodynamic parameters and concentrations of Nt-pro-ANP and Nt-pro-BNP were measured. RESULTS: Central venous pressure and pulmonary capillary wedge pressure increased significantly during the elevation of intra-abdominal pressure (IAP) and returned to baseline after abdominal desufflation. Right and left transmural pressures remained unaffected by the elevation of IAP. Cardiac output decreased in phases T2 and T3 and was restored to baseline levels after abdominal desufflation. Systemic and pulmonary vascular resistances increased significantly with IAH and decreased after abdominal desufflation. Nt-pro-ANP did not change significantly in comparison to baseline. Nt-pro-BNP increased significantly in comparison to baseline at T3 and T4. Peak Nt-pro-BNP levels at T3 (peak IAP) correlated positively with indices of afterload at this time point, that is, systemic vascular resistance and pulmonary vascular resistance (r(2) = 0.38, P = 0.042 and r(2) = 0.55, P = 0.009, respectively). A strong negative correlation between Nt-pro-BNP and cardiac output at T3 was also demonstrated (r(2) = 0.58, P = 0.006). CONCLUSIONS: IAH resulted in cardiovascular compromise. The unchanged Nt-pro-ANP concentrations might reflect unaltered atrial stretch with IAH, despite the elevation of right atrial filling pressure. The significant increase of Nt-pro-BNP in response to high levels of IAP may reflect left ventricular strain and dysfunction due to the severe IAH and provide an alternative marker in the monitoring of IAH.

Ischemic preconditioning confers antiapoptotic protection during major hepatectomies performed under combined inflow and outflow exclusion of the liver. A randomized clinical trial.

BACKGROUND: Extensive experimental studies and a few clinical series have shown that ischemic preconditioning (IPC) attenuates oxidative ischemia/reperfusion (I/R) injuries in liver resections performed under inflow vascular control. Selective hepatic vascular exclusion (SHVE) employed during hepatectomies completely deprives the liver of blood flow, as it entails simultaneous clamping of the portal triad and the main hepatic veins. The aim of the present study was to identify whether IPC can also protect hepatocytes during liver resections performed under SHVE. METHODS: Patients undergoing major liver resection were randomly assigned to have either only SHVE (control group, n = 43) or SHVE combined with IPC--10 min of ischemia followed by 15 min of reperfusion before SHVE was applied (IPC group, n = 41). RESULTS: The two groups were comparable with regard to age, liver resection volume, blood loss and transfusions, warm ischemic time, and total operative time. In liver remnant biopsies obtained 60 min post-reperfusion, IPC patients had significantly fewer cells stained positive by TUNEL compared to controls (19% +/- 8% versus 45% +/- 12%; p < 0.05). Also IPC patients had attenuated hepatocyte necrosis, systemic inflammatory response, and oxidative stress as manifested by lower postoperative peak values of aspartate transaminase, interleukin-6, interleukin-8, and malondialdehyde compared to controls. Morbidity was similar for the two groups, as were duration of intensive care unit stay and extent of total hospital stay. CONCLUSIONS: In major hepatectomies performed under SHVE, ischemic preconditioning appears to attenuate apoptotic response of the liver remnant, possibly through alteration of inflammatory and oxidative pathways.

Malignant insulinoma in childhood.

Pancreatic tumors constitute a rare surgical problem in infancy and childhood. Insulinomas are rare in all age groups with an estimated incidence of one per 250,000 person-years and even rarer in childhood. We report a 10 year-old girl with malignant insulinoma. The presenting symptom was hypoglycemic attacks. Laboratory investigation demonstrated that the hypoglycemia was due to hyperinsulinism. MRI of the abdomen revealed a mass at the tail of the pancreas. Distal pancreatectomy with splenectomy was performed. Histological examination showed malignant insulinoma with peripancreatic lymph node metastases. One month later abdominal MRI revealed the existence of multiple small metastatic foci in the liver, which were confirmed by In111 octreoscan. Treatment with octreotide was started and the disease is stable after 12 months of therapy.

Should procalcitonin be introduced in the diagnostic criteria for the systemic inflammatory response syndrome and sepsis?

PURPOSE: To define whether procalcitonin should be introduced in the diagnostic criteria of sepsis. METHODS: Procalcitonin was estimated in sera of 105 critically ill patients by an immunochemiluminometric assay. Diagnosis was settled by 3 types of criteria: A, the American College of Chest Physicians/Society of Critical Care Medicine (ACCP/SCCM) 1992 criteria; B, the ACCP/SCCM criteria and concentrations of procalcitonin above 1.0 ng/mL as indicative of SIRS/sepsis; and C, the ACCP/SCCM criteria and concentrations of procalcitonin 0.5 to 1.1 ng/mL for SIRS and above 1.1 ng/mL for sepsis. RESULTS: Criteria A identified 50.5% of patients with SIRS, 18.1% with sepsis, 0.9% with severe sepsis and 22.9% with septic shock; respective diagnosis by criteria B were 26.7%, 9.5%, 10.5% and 25.7%; and respective diagnosis by criteria C were 19.0%, 25.7%, 9.5%, and 25.7%. Sensitivity of concentrations between 0.5 ng/mL and 1.1 ng/mL was 25.6% for Systemic Inflammatory Response Syndrome (SIRS); and above 1.1 ng/mL 92.8% for sepsis. Sepsis-related death was associated with elevated procalcitonin upon presentation of a clinical syndrome. CONCLUSIONS: Despite the limited diagnostic value of procalcitonin for SIRS, concentrations of procalcitonin above 1.1 ng/mL are highly indicative for sepsis without, however, excluding the presence of SIRS.