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Background In severe falciparum malaria, unlike sepsis, hypotension on admission is uncommon. We hypothesized that low nitric oxide bioavailability due to the presence of cell-free hemoglobin (CFH) increases vascular tone in severe malaria. Methods Patients with severe malaria (n = 119), uncomplicated malaria (n = 91), or suspected bacterial sepsis (n = 56), as well as healthy participants (n = 50), were recruited. The systemic vascular resistance index (SVRI) was estimated from the echocardiographic cardiac index and the mean arterial pressure. Results SVRI and hematocrit levels were lower and plasma CFH and asymmetric dimethylarginine levels were higher in patients with malaria, compared with healthy participants. In multivariate linear regression models for mean arterial pressure or SVRI in patients with severe malaria, hematocrit and CFH but not asymmetric dimethylarginine were significant predictors. The SVRI was lower in patients with suspected bacterial sepsis than in those with severe malaria, after adjustment for hematocrit and age. Plasma CFH levels correlated positively with the core-peripheral temperature gradient and plasma lactate levels and inversely with the perfusion index. Impaired peripheral perfusion, as reflected by a low perfusion index or a high core-peripheral temperature gradient, predicted mortality in patients with severe malaria. Conclusions CFH is associated with mean arterial pressure, SVRI, and peripheral perfusion in patients with severe malaria. This may be mediated through the nitric oxide scavenging potency of CFH, increasing basal vascular tone and impairing tissue perfusion.

BACKGROUND: Lactic acidosis with an elevated lactate-pyruvate ratio suggesting anoxia is a common feature of severe falciparum malaria. High lactate levels are associated with parasitized erythrocyte sequestration in the microcirculation. To assess if there is an additional contribution to hyperlactataemia from relatively inadequate total oxygen delivery, oxygen consumption and delivery were investigated in patients with malaria. METHODS: Adult Bangladeshi and Indian patients with uncomplicated (N = 50) or severe (N = 46) falciparum malaria or suspected bacterial sepsis (N = 27) and healthy participants as controls (N = 26) were recruited at Chittagong Medical College Hospital, Chittagong, Bangladesh and Ispat General Hospital, Rourkela, India. Oxygen delivery (DO2I) was estimated from pulse oximetry, echocardiographic estimates of cardiac index and haematocrit. Oxygen consumption (VO2I) was estimated by expired gas collection. RESULTS: VO2I was elevated in uncomplicated median (IQR) 185.1 ml/min/m2 (135-215.9) and severe malaria 192 ml/min/m2 (140.7-227.9) relative to healthy persons 107.9 ml/min/m2 (69.9-138.1) (both p CONCLUSIONS: Reduced total oxygen delivery is not a major contributor to lactic acidosis in severe falciparum malaria.

Context Insulinomas, which are generally smaller than 2 cm, may be difficult to detect by routine imaging modalities including abdominal ultrasonography, computed tomography, and magnetic resonance imaging. Although preoperative detection of insulinomas is essential for operative planning, it is often challenging due to their small size. While arterial stimulation and venous sampling has been used in patients with insulinomas it has been largely supplanted by early-phase thin-slice computed tomography. Case report We report three patients with insulinomas, which were not detected by routine computed tomography scan, but were successfully imaged using early-phase thin-slice computed tomography. Enucleation was performed in all patients based on preoperative imaging. All three patients had an unremarkable postoperative course. Conclusion Early-phase thin-slice computed tomography is recommended for the preoperative identification of insulinomas. This non-invasive imaging technique should be considered before performing arterial stimulation and venous sampling. Image. CT scan before and 35, 55, and 80 seconds after the administration of contrast agent., JOP. Journal of the Pancreas, Vol 16, No 1 (2015): January - p. 1-98