Cerebral blood flow and the development of ammonia-induced brain edema in rats after portacaval anastomosis.

Two mechanisms may account for brain edema in fulminant hepatic failure: the osmotic effects of brain glutamine, a product of ammonia detoxification, and a change of cerebral blood flow (CBF). We have shown brain edema, a marked increase in brain glutamine, and a selective rise in CBF in rats after portacaval anastomosis receiving an ammonia infusion. In this study, we inhibited the activity of glutamine synthetase with methionine-sulfoximine (MSO) and examined ammonia levels, brain water and CBF. Four groups received either a continuous ammonium acetate or control infusion; half of the animals had been pretreated with MSO or vehicle. The ammonia group exhibited brain edema (79.97 +/- 0.04 vs. 81.11 +/- 0. 13% water), an increase in cerebrospinal fluid (CSF) glutamine (1.29 +/- 0.21 vs. 2.84 +/- 0.39 mmol/L) and CBF (63 +/- 11 vs. 266 +/- 45 mL/min/100 g brain). When MSO was added to the ammonia infusion, ammonia levels rose further (928 +/- 51 vs. 1,293 +/- 145 mmol/L, P <.05) but CSF glutamine decreased (2.84 +/- 0.39 vs. 1.61 +/- 0.2 mmol/L, P <.01). Brain edema (80.48 +/- 0.11%) and cerebral hyperemia (140 +/- 25 mL/min/100 g brain) were significantly ameliorated in the ammonia plus MSO group. Brain output of circulating nitric oxide (NO(x)) was increased in the ammonia-infused group but normalized in the ammonia plus MSO group. In this model, the rise of CBF reflects intracranial events that occur after glutamine synthesis. Activation of nitric oxide synthase in the brain could account for these findings.     

Leg Endoscopic Groin Lymphadenectomy (LEG Procedure): Step-by-Step Approach to a Straightforward Technique

Background

Inguinofemoral lymphadenectomy can serve as a diagnostic and potentially therapeutic procedure in a variety of malignancies, including those of the genitalia and the skin. Historically, this procedure was associated with significant morbidity.

Objective

We hypothesized that both superficial and deep groin dissection (complete inguinofemoral lymphadenectomy) could be performed endoscopically, in a step-by-step manner, with low morbidity, including those patients with obesity and previously treated groins.

Design, setting, and participants

Twenty-five groin dissections were undertaken in 16 patients, male and female, over a 12-mo time period.

Surgical procedure

The femoral triangle was marked. An initial fingers’ breadth–sized incision was made 3 cm below the apex of the femoral triangle. Finger dissection was used to develop the skin flaps at the apex of the triangle out to two additional 10-mm ports. The anterior space was dissected, and, following that, the saphenous vein was transected distally with an endoscopic stapler. The lateral planes on the adductor longus and sartorius muscles were developed, and, finally, the posterior plane was developed, lifting the packet off the fascia lata. Deep femoral nodes were removed as well. The saphenofemoral junction was transected and the packet was removed. A drain was placed.

Measurements

The number of lymph nodes harvested was recorded. The development of skin complications, leg edema, and deep venous thrombosis was recorded as well.

Results and limitations

The average length of procedure was 147 min. The mean number of lymph nodes harvested was nine. A groin seroma requiring further drainage was observed in one patient. Cellulitis was observed in two patients.

Conclusions

Leg endoscopic groin lymphadenectomy (LEG procedure) is straightforward to learn, with operative times that parallel the open procedure. Less morbidity has been observed in our first group of patients compared to contemporary open series.     

Grade migration in prostate cancer: an analysis using the Surveillance, Epidemiology, and End Results registry

To utilize the Surveillance, Epidemiology, and End Results (SEER) registry to examine trends in grade assignment. Data from 411 325 patients from 1984 to 2003 were analyzed for grade migration and for cause-specific survival (CSS) as a function of grade. There has been a significant grade migration during the study period (P<0.001), principally from well-differentiated (WD) to moderately differentiated (MD) disease. Five-year CSS of MD and WD patients have converged, suggesting a decreasing role of grade as a prognostic factor. A grade migration from WD to MD assignment has occurred, suggesting that prognostic categorizations based on grade across eras may be difficult to interpret.