K Luhmann | PubMed Health

PubMed1989

Duplex ultrasound evaluation of normal native kidneys and native kidneys with urinary tract obstruction.

The average resistive indices of 15 native kidneys from 8 patients with no known renal dysfunction were determined with the Doppler waveform obtained from the interlobar arteries. The average resistive index for this group was .58; the highest value was .66. The interlobar arteries of four native kidneys with urinary tract obstruction as well as those of the contralateral unobstructed kidneys were evaluated by Duplex ultrasound. Unilateral urinary tract obstruction was due to a congenital ureteropelvic junction obstruction in one patient or an acutely obstructing calculus at the ureterovesical junction in three patients. The average resistive index of the four obstructed kidneys was .75 and the lowest value was .71. The average resistive index of the four contralateral unobstructed kidneys in these patients and the 15 kidneys from patients with no known renal abnormalities was .58, which was significantly different from the value for the obstructed kidneys (p less than .005). The resistive index from the interlobar arteries of normal native kidneys is reproducible as previously reported in renal transplants. Pathologic renal processes, such as urinary tract obstruction, may be characterized by abnormally high resistive indices.

Adolescent↗

PubMed1988

Left ventricular function during chronic endotoxemia in swine.

Cardiac performance was studied in 15 chronically instrumented awake pigs during chronic endotoxemia (CET) induced by intravenous infusion of low doses of endotoxin. We sought to test the hypothesis that left ventricular inotropic state was depressed during the stage of chronic endotoxemia when cardiac output, heart rate, and left ventricular systolic pressures are elevated, termed "hyperdynamic sepsis". Left ventricular pressure, internal short axis diameter (SAX), pulmonary artery blood flow, and electrocardiogram were recorded. After initial surgical preparation, each pig was observed for 7-10 days to measure representative basal values. Each pig was then reoperated on day 10 to implant an endotoxin-loaded osmotic pump whose output, infused Salmonella enteritidis endotoxin at a rate calculated to be 10 micrograms.kg-1.h-1 for up to 7 days. Cardiac performance was monitored by measuring dP/dt, heart rate, stroke volume, end-diastolic diameter, percent change in diameter, and the slope of the end-systolic pressure diameter relationship (ESPDR). Data from the basal days were pooled and compared with the data obtained each day of CET by two-way analysis of variance. Ten of 15 pigs survived more than 2 days of CET; 5 died before the morning of the second CET day. The surviving pigs demonstrated elevated systolic pressures, left ventricular maximum rate of pressure development (+dP/dtmax and -dP/dtmax), heart rates, and cardiac output. However, both ESPDR and percent SAX shortening were significantly depressed during both CET days. We conclude that cardiac inotropic state is depressed during hyperdynamic sepsis as indicated by the load-independent parameter ESPDR and confirmed by depressed percent SAX shortening.

Analysis of Variance↗