Bruno Ferreira Viana

Reprodutibilidade do VO2Máx estimado na corrida pela frequência cardíaca e consumo de oxigênio de reserva

The objective was to determine the reliability of the VO2Max estimate on a treadmill using the measured (HRpeak) vs. the predicted (HRpredicted) maximum heart rate (HR). Eighteen men (27.5 ± 7.1 years, 73.7± 12.6 kg, 174.8 ± 10.2 cm) performed, in the first visit, a progressive test to determine the HRpeak. In the two following visits, submaximal aerobic tests were performed on a treadmill with a 6 min at 75% HR reserve. VO2Max was estimated by means of the equations of HR, VO2 reserve and the ACSM running equation. The intraclass correlation coefficient and the typical error of measurement using HRPredicted and HRpeak were 0.89, 2.43 ml.kg-1.min-1 (5%) and 0.83, 2.43 mL.kg-1.min-1 (4.9%), respectively. There was no significant difference (t test) between the estimates of VO2Max from the HRpeak and HRpredicted. The use of the HRpredicted was considered appropriate for VO2Max estimation, with a small typical error of measurement.

A one-step procedure by using linear echoendoscope to perform EUS-guided choledochoduodenostomy and duodenal stenting in patients with irresectable periampullary cancer

Objective: Endoscopic ultrasound-guided choledochoduodenostomy (EUS-CD) has become an alternative method after unsuccessful endoscopic retrograde cholangiopancreatography (ERCP) treatment. We present a case series study and its feasibility by using only a linear therapeutic channel echoendoscope to create both a biliary-enteral fistula and anatomic enteral recanalization. Methods: We presented seven cases of unresectable periampullary cancer with both biliary and duodenal obstruction. In these cases, the EUS-guided technique might be an alternative to double stenting (biliary and enteral) in the same procedure and equipment. Results: In all cases, the location of the biliary obstruction was in the distal common bile duct (CBD) and the grade of proximal dilation diameter varied from 15 mm to 20 mm. Two patients had type I (28.6%) and five had type II (71.4%) duodenal obstruction. Technical success of EUS-CD, by the stent placement, occurred in 100% of the cases. There were no early complications. Biliary drainage was effective clinically as well as in laboratory in 6 cases (6/7), by relieving obstructive jaundice and decreasing bilirubin levels. Conclusion: EUS equipment may offer an alternative to double stenting in the same procedure and with palliative propose.

TRADITIONAL MODELS OF FATIGUE AND PHYSICAL PERFORMANCE

The origin of fatigue has been the focus of studies involved in sports performance, due to the necessity to clarify the mechanistic bases for the reduced capacity to perform considerable effort intensities. According to the traditional conception of fatigue, mechanisms may encompass peripheral and central sites of fatigue. Peripheral fatigue is understood as events related to an inefficient tissue oxygen delivery, metabolic accumulation, muscular acidosis and muscle substrate depletion. In contrast, the central fatigue is mostly related to events in the central nervous system (CNS) that may involve neurotransmitters changes, altered metabolic profile and elevated temperature. Therefore, the current review aimed to discuss the peripheral and central mechanisms of fatigue, thus driving interpretations of the phenomenon. Palavras-chave: Oxygen. Muscle glycogen. Exercise limitation.