Perfusion monitoring

Schnittger, C., Weissenborn, K., Boker, K., Kolbe, H., Dengler, R., Manns, M.R 1997. Continuous noninvasive cerebral perfusion monitoring in fulminant hepatic failure and brain oedema. In Advances in Hepatic Encephalopathy Metabolism in Liver Disease, eds C. Record and H. A1 Mardini (eds.)., pp. 515-519. New Castle upon Tyne Medical Faculty of the University of Newcastle upon Tyne... 

Fig 1. Monitoring set up (a) conqiuler, (b) box containing air pressure transducers, (c) interflice pressure monitor (d) perfusion monitor, (e) mouse, (f) keyboard, (g) printer, (h) computer screen and (i) IPC pump. 

Skin blood flow (SBF) was measured using a laser Doppler blood perfusion monitor (Vasamedics Laserflo Blood Perfusion Monitor BPM ). The monitor was cormected to the computer via the computer s USB port The sensor used to monitor the superficial skin blood flow fed data into the monitor, and this data was collated by a voltage data logger this was then offloaded to the computer s OTLM programme. OTLM recorded the electrical signal produced by the flow of blood in the superficial vessels in the skin, and thus, as for humidity, the units of the raw data were millivolts (mV). 

Additionally, it was found that in human forearm cutaneous vessels, menthol caused a profound dilatation in an assay where cutaneous red cell flux (RCF) was recorded from the ventral surface of the left forearm using a laser Doppler perfusion monitor. The delay in action (8-18 min) in relation to what was observed in other vessels may simply reflect the time taken for menthol to passively diffuse into blood vessels from which RCF measurements were taken, 1 mm below the skin surface [16]. This observation is of particular relevance to demonstrate that experiments conducted in humans seems to reflect similar vasorelaxation effects observed in rats. 

Hoff D.A, Gregersen H, and Hatlebakk J.G (2009) Mucosal blood flow measurements using laser Doppler perfusion monitoring. World... 

Laser Speckle Contrast Imaging for Perfusion Monitoring in Burn Tissue... 

INEFFECTIVE TISSUE PERFUSION RENAL The patient taking an aminoglycoside is at risk for nephrotoxicity. The nurse measures and records the intake and output and notifies the primary health care provider if the output is less than 750 ml/day. It is important to keep a record of the fluid intake and output as well as a daily weight to assess hydration and renal function. The nurse encourages fluid intake to 2000 ml/day (if the patient s condition permits). Any changes in the intake and output ratio or in the appearance of the urine may indicate nephrotoxicity. The nurse reports these types of changes to the primary health care provider promptly. The primary health care provider may order daily laboratory tests (ie, serum creatinine and blood urea nitrogen [BUN]) to monitor renal function. The nurse reports any elevation in the creatinine or BUN level to tiie primary health care provider because an elevation may indicate renal dysfunction. 

RISK FOR INEFFECTIVE TISSUE PERFUSION RENAL When the patient is taking a drag tiiat is potentially toxic to die kidneys, die nurse must carefully monitor fluid intake and output. In some instances, die nurse may need to perform hourly measurements of die urinary output. Periodic laboratory tests are usually ordered to monitor the patient s response to therapy and to detect toxic drag reactions. Seram creatinine levels and BUN levels are checked frequentiy during the course of therapy to monitor kidney function. If the BUN exceeds 40 mg dL or if the serum creatinine level exceeds 3 mg cIL, the primary health care provider may discontinue the drug therapy or reduce the dosage until renal function improves. 

It should be remembered that with the possible exception of voltammetry when the monitoring electrode is sufficiently small to reach synapses, it is not the actual release of the NT that is being measured in perfusion studies. It is overflow. As discussed previously, most of any released NT is either physically restricted to the synapse or destroyed before it can diffuse away. 

Monitor for adequate perfusion of vital organs through assessment of mental status, creatinine clearance, liver function tests, and a stable HR between 50 and 100 beats per minute. Additionally, adequate skin and muscle blood perfusion and normal pH is desirable. 

Normal saline or dopamine at renal perfusion dose of 2 mcg/kg per minute for oliguria monitor for electrolyte abnormalities and replace as indicated. 

Concentration and MWD of F-PHEA After Absorption. F-PHEA was determined in perfusate samples by quantitative GPC relative to a freshly prepared F-PHEA standard run on the same day. Either a mixed-bed column (12 x 300 mm Sephacryl S-200 Sephadex G-25 SF 3 1, Pharmacia LKB) or a Separon HEMA-Bio 40 column (8 x 250 mm 10 pm particle size, Tessek A/S, Aarhus, Denmark) was used with a 20 pL injection volume. A mobile phase of pH 7.4 phosphate buffered saline (0.05 M phosphate, 0.15 M NaCl) was supplied (Model LC-7A Bio Liquid Chromatograph, Shimadzu Corporation, Kyoto, Japan) at 0.5 or 1 mL/min. Fluorescent detection was employed (Model RF-535 Fluorescence HPLC Monitor,... 

Tang W., Weil M.H., Sun S., Noc M., Gazmuri R.J., Bisera J., Gastric intramural pC02 as monitor of perfusion failure and anaphylactic shock, J. Appl. Physiol. 1994 76 572-577. 

Coronary perfusion pressure should be assessed in patients for whom intraarterial monitoring is in place. 

Fluid status is assessed by monitoring urine output and specific gravity, serum electrolytes, and weight changes. An hourly urine output of at least 1 mL/kg for children and 50 mL for adults is needed to ensure tissue perfusion. 

Rat peritoneal mast-cell exocytosis (as monitored by membrane capacitance measurements) in response to either antigenic stimulation or to the intracellular perfusion with guanine nucleotides (for example, GTP[AS]), occurs after a measurable lag period which has been suggested to be due to the involvement of a GTP-binding regulatory protein [202]. In contrast, stimula-... 

---