Effect of systemic pH, PCO2 and bicarbonate concentration on biliary bicarbonate secretion in the rat

The effect of acute metabolic or respiratory acid-base disturbances on biliary bicarbonate secretion was examined in bile fistula rats. Animals were infused with ursodeoxycholate at a rate that stimulates bicarbonate secretion (1 mumole . min-1 X 100 gm-1), in control conditions and during acute acid-base disturbances. Metabolic acidosis or alkalosis were induced by HCl or NaHCO3 infusions, and respiratory acidosis or alkalosis were created respectively by adding CO2 to the inspired gas or by hyperventilation in artificially ventilated animals. Biliary bicarbonate concentration was always higher than plasma bicarbonate concentration. During metabolic disturbances, changing the plasma bicarbonate concentration from 9.2 to 30.2 mM stimulated biliary bicarbonate secretion by 113%. During respiratory disturbances, changing the plasma PCO2 from 25.5 to 59.8 mm Hg also increased biliary bicarbonate secretion by 89%. Biliary bicarbonate output was thus independent of plasma pH. When all animals were considered, bile flow was positively correlated with biliary bicarbonate concentration (r = 0.71, p less than 0.001). Acetazolamide significantly decreased ursodeoxycholate-induced bile flow and bicarbonate secretion by 20 and 22%, respectively. These results support the hypothesis that there is a relationship between ursodeoxycholate-induced bicarbonate secretion and bile flow. They are also consistent with the view that ursodeoxycholate-stimulated biliary bicarbonate secretion in the rat is strongly affected by plasma bicarbonate and PCO2, but not by plasma pH, and involves carbonic anhydrase.     

Pain relief following Arthroscopy - a comparative study of Intra-articular Bupivacaine,Morphine and Neostigmine

Pain after arthroscopy is quite distressing. Intra-articular bupivacaine produces transient analgesia and reports of analgesia using intra-articular opioids have produced conflicting results. Recently, spinal administration of neostigmine was shown to produce dose-dependant analgesia. However, this was limited by adverse effects. The purpose of this study was to compare the effects on intra-articular neostigmine, bupivacaine and morphine. 75 patients were randomized to receive intra-articular saline, bupivacaine, morphine, neostigmine and bupivacaine-neostigmine after arthroscopic surgery under spinal anaesthesia. Visual analog pain scores (VAS), duration of analgesia as defined as time for first demand for parenteral opioids and the total subsequent consumption of morphine was evaluated. Intra-articular bupivacaine resulted in significant VAS reduction at one and four hours as compared to those receiving intra-articular saline and morphine. Analgesia lasted longer after 500ugm intra-articular neostigmine as compared with bupivacaine, morphine or saline. The need for supplementary analgesia was lowest in the neostigmine group as compared to the other groups. No significant difference was found if bupivacaine was added to neostigmine. Among all the groups, no significant side-effects were observed.Key Words: Arthroscopy, Bupivacaine, Morphine, Neostigmine     

The potential impact of nonpharmacologic population-wide blood pressure reduction on coronary heart disease events: pronounced benefits in African-Americans and hypertensives

BACKGROUND: Previous estimates of the population-wide impact of nonpharmacologic interventions that lower blood pressure (BP) have typically assumed a uniform response to the intervention. However, several nonpharmacologic interventions reduce BP to a greater degree in hypertensives and African-Americans. METHODS: We used the Framingham risk equation and data from the Third National Health and Nutrition Examination Survey (NHANES III) to estimate the number of coronary heart disease (CHD) events that would be prevented in the United States assuming a population-wide adoption of the DASH (Dietary Approaches to Stop Hypertension) diet under three scenarios: (1) an overall uniform systolic blood pressure (SBP) shift, (2) race-specific uniform SBP shifts, and (3) race-specific progressive SBP shifts. The uniform shifts were the mean SBP reductions from the DASH trial. The progressive shifts were derived by modeling the change in SBP as a function of baseline SBP in DASH. RESULTS: Applying an overall uniform SBP reduction of 5.5 mm Hg (the mean reduction in DASH), we predicted a reduction of 668,426 CHD events over 10 years (60,230 in African-Americans and 608,196 in whites). Applying race-specific uniform SBP reductions (6.8 mm Hg for African-Americans and 3.0 mm Hg for whites), we predicted a reduction of 406,432 CHD events (74,401 in African-Americans and 332,031 in whites). After accounting for race and baseline SBP, we predicted a reduction of 416,514 CHD events (94,828 in African-Americans and 321,080 in whites). While whites would be expected to have a greater absolute reduction in CHD events, African-Americans would be expected to experience a greater relative reduction in CHD events. CONCLUSION: Models that estimate the population-wide impact of BP reduction strategies should take into account the baseline distribution of BP and differential effects in subgroups. Population-wide adoption of a healthy dietary pattern should have a substantial impact on the incidence of CHD in the United States, especially among African-Americans. Additional studies are needed to assess the impact of the DASH diet on CHD risk in free-living subjects.     

Natural history of focal nodular hyperplasia. A retrospective study of 44 cases

AIM: To evaluate the natural course of focal nodular hyperplasia according to hormonal status. METHODS: Forty-four patients were included in this retrospective study. Tumor size was assessed with ultrasound examination. We studied the influence of hormone status on the course of the disease. RESULTS: All patients were women, the median age at diagnosis was 35 years and the median follow-up was 45 months. Ten patients were symptomatic at diagnosis, while none were symptomatic at the end of follow-up. The median size of the lesions was 56 mm. No complications occurred. The size of the tumor remained stable in 19 patients, increased in 12 and decreased in 13. Twenty-one of 37 patients stopped taking oral contraceptives at diagnosis: the lesion remained stable in 11 patients, increased in 3 and decreased in 7. Two patients didn't stop taking oral contraceptives: the lesion increased in one, decreased in the other. Six patients became pregnant and 6 patients went into menopause during follow-up: the lesion remained stable in 3 and 4 patients respectively. CONCLUSION: Focal nodular hyperplasia is a benign lesion. Tumor size remained stable in most cases. It seems that the hormonal status has little or no influence on the course of the disease.     

Pancreaticoduodenectomy with vascular reconstruction for adenocarcinoma of the pancreas with borderline resectability

AIM: To analyze whether pancreaticoduodenectomy with simultaneous resection of tumor-involved vessels is a safe approach with acceptable patient survival.METHODS: Between January 2001 and March 2012, 136 patients received pancreaticoduodenectomy for adenocarcinoma at our hospital. Seventy-eight patients diagnosed with pancreatic head carcinoma were included in this study. Among them, 46 patients received standard pancreaticoduodenectomy (group 1) and 32 patients received pancreaticoduodenectomy with simultaneous resection of the portal vein or the superior mesenteric vein or artery (group 2) followed by reconstruction. The immediate surgical outcomes and survivals were compared between the groups. Fifty-five patients with unresectable adenocarcinoma of the pancreas without liver metastasis who received only bypass operations (group 3) were selected for additional survival comparison.RESULTS: The median ages of patients were 67 years (range: 37-82 years) in group 1, and 63 years (range: 35-86 years) in group 2. All group 2 patients had resection of the portal vein or the superior mesenteric vein and three patients had resection of the superior mesenteric artery. The pancreatic fistula formation rate was 21.7% (10/46) in group 1 and 15.6% (5/32) in group 2 (P = 0.662). Two hospital deaths (4.3%) occurred in group 1 and one hospital death (3.1%) occurred in group 2 (P = 0.641). The one-year, three-year and five-year overall survival rates in group 1 were 71.1%, 23.6% and 13.5%, respectively. The corresponding rates in group 2 were 70.6%, 33.3% and 22.2% (P = 0.815). The one-year survival rate in group 3 was 13.8%. Pancreaticoduodenectomy with simultaneous vascular resection was safe for pancreatic head adenocarcinoma.CONCLUSION: The short-term and survival outcomes with simultaneous resection were not compromised when compared with that of standard pancreaticoduodenectomy.