Liu Q, Fehring C, Lowry TF, Wong-Riley MTT. Postnatal development of metabolic rate during normoxia and acute hypoxia in rats: implication for a sensitive period. J Appl Physiol 106: 1212-1222, 2009. First published December 31, 2008 doi:10.1152/japplphysiol.90949.2008.-Previously, we reported that the hypoxic ventilatory response (HVR) in rats was weakest at postnatal day (P) P13, concomitant with neurochemical changes in respiratory nuclei. A major determinant of minute ventilation (V E) is reportedly the metabolic rate [O2 consumption (V O2) and CO2 production (V CO2)]. The present study aimed at testing our hypothesis that daily metabolic rates changed in parallel with ventilation during development and that a weak HVR at P13 was attributable mainly to an inadequate metabolic rate in hypoxia. Ventilation and metabolic rates were monitored daily in P0 -P21 rats. We found that 1) ventilation and metabolic rates were not always correlated, and V E/V O2 and V E/V CO2 ratios were not constant during development; 2) metabolic rate and V E/V O2 and V E/V CO2 ratios at P0 -P1 were significantly different from the remaining first postnatal week in normoxia and hypoxia; 3) at P13, metabolic rates and V E/V O2 and V E/V CO2 ratios abruptly increased in normoxia and were compromised in acute hypoxia, unlike more stable trends during the remaining second and third postnatal weeks; and 4) the respiratory quotient (V CO2/V O2) was quite stable in normoxia and fluctuated slightly in hypoxia from P0 to P21. Thus our data revealed heretofore unsuspected metabolic adjustments at P0 -P1 and P13. At P0 -P1, ventilation and metabolic rates were uncorrelated, whereas at P13, they were closely correlated under normoxia and hypoxia. The findings further strengthened the existence of a critical period of respiratory development around P13, when multiple physiological and neurochemical adjustments occur simultaneously. carbon dioxide production; critical period; oxygen consumption; respiratory quotient; ventilation PREVIOUSLY, WE CONDUCTED DETAILED, day-to-day studies of various brain stem respiratory nuclei of the rat and found that neurotransmitters and receptors underwent distinct developmental changes. Significantly, at or around postnatal day (P) 12, the expression of excitatory neurotransmitter glutamate and its N-methyl-D-aspartate receptors dropped precipitously, whereas the expression of inhibitory neurotransmitter ␥-aminobutyric acid (GABA), GABA B receptors, and glycine receptors rose sharply (27,30, 61). Concomitantly, there was a sudden fall in cytochrome oxidase activity (27,28, 61), a sensitive indicator of metabolic capacity and neuronal activity (60). We hypothesized that at and around P12 is a sensitive period in the postnatal development of the rat's respiratory control network, when a transient dominance of inhibitory over excitatory neurotransmission renders the animals less capable of overcoming exogenous respiratory stressors. Our subsequent ventilatory studies revealed striking changes in normoxic ventilation ...

Cardiovascular reactivity to ergometric exercise was studied on work loads of 60, 80 and 100 W in 16 young and middle-aged males with mild hypertension and 17 normotensive subjects of the same age. The middle-aged hypertensive group showed a stronger rise in systolic blood pressure to a 100-watt work load than the matched normotensive group. Cardiovascular reactivity was not different with work loads of 60 and 80 W, and young hypertensives and normotensives had the same reactions. Thus cardiovascular reactivity to exercise is dependent on both blood pressure and age

Introduction:We looked at the reasons why fluorescent cholangiography (FC) should be used routinely in laparoscopic cholecystectomy (LC). Method: A single dose of 0.05 mg/kg of Indocyanin Green (ICG) was administered intravenously one hour prior to the surgery to perform fluorescent cholangiograhy. Results: FC could be performed in all 45 (100%) patients whereas intra-operative cholangiography (IOC) could be performed in 42 out of 45 (93%) patients (p < 0.078). Individual median cost of performing FC was cheaper than IOC (13.97 ± 4.3 vs 778.43 ± 0.4 US dollars per patient, p = 0.0001). The mean operative time was 64.95 ± 17.43 minutes. FC was faster than IOC (0.71 ± 0.26 vs 7.15 ± 3.76 minutes, p < 0.0001). The cystic duct was identified by FC in 44 out of 45 patients (97.77 %). The residents were able to identify the extrahepatic structures in all 45 cases (100%) with FC. No complications were detected related to surgery and the use of FC. Learning curve was not necessary to identify structures using FC. X-ray leads were only used for IOC. FC could be performed by all residents at different level of training in 100% of the cases. Smooth dissection, transection and resection could be safely performed in 45 cases (100%). Conclusion: Fluorescent cholangiography seems to be feasible, cheap, expeditious, useful, an effective teaching tool, safe, no learning curve is necessary, does not require x-ray and easy to perform. It can be used for real time surgery to delineate the extrahepatic biliary structures.Background: Objective of this study is to compare rates of pancreatic fistulas and complications following the Whipple operation between pancreaticojejunostomy (PJ) and pancreaticogastrostomy (PG).Methods: 98 patients undergoing Whipple resection were randomized to either PG (48) or PJ (50) reconstruction. T-test and Chi-square tests were used for intention to treat data analysis. Logistic regression was used to measure the influence of surgical technique, preoperative ASA score and soft pancreatic gland on overall complications, severe post operative complications and overall fistula rates. Results: The rate of pancreatic fistula formation was 18% (Grade A = 6%, B = 10%, C = 2%) in the PJ arm and 25% (Grade A = 8%, B = 13%, C = 4%) in the PG arm, p = 0.399. The rate of postoperative complications was 48% (Clavien 1 = 14%, 2 = 36%, 3 = 10%, 4 = 0%, 5 = 2%) in the PJ and 58% (Clavien 1 = 21%, 2 = 38%, 3 = 25%, 4 = 6%, 5 = 4%) in the PG arm, p = 0.306. There was a significant difference in severe complications (Clavien 3-5) with 12% in the PJ and 31% in the PG arm, p = 0.02. In the multivariate analysis randomization (together with ASA) was only predictive of severe complications (OR 0.10, p < 0.005 for randomization to PJ reconstruction; OR 11.58, p < 0.05 for ASA 2 and OR 30.89, p < 0.05 for ASA 3 compared to ASA 1). Conclusion: Results of the study suggest that while there are no overall differences in rates of pancreatic leak/fistula and overall complications between PG and PJ arms, pancreaticogastrostomy is associ...