Regional perfusion monitoring

Nordstrom CH, Reinstrup P, Xu W, Gardenfors A, Ungerstedt U. 2003. Assessment of the lower limit for cerebral perfusion pressure in severe head injuries by bedside monitoring of regional energy metabolism. Anesthesiology 98(4) 809-814. 

Commonly measured and calculated hemodynamic and oxygen-transport indices associated with invasive monitoring are primarily global indicators of tissue perfusion. There have been attempts to And regional and local indicators of hypoperfusion so that circulatory insufficiency could be treated before overt shock occurs. One focus of recent research has been monitoring modalities involving the gastrointestinal tract. 

Fig. 5.9 Prediction of infarct growth. A 65-year-old man, improving clinically at 5 h postictus, was monitored in the Neurology ICU based on his labile blood pressure, a fixed left M2 occlusion on CTA, and a significant core/penumbra mismatch on CTP/MRP. His 24-h follow-up DWI showed a small infarction. However, 24 h after cessation of hypertensive therapy there was infarct growth into the region of penumbra. Admission CTA (top) CTP (CBV/CBF/ MTT) at 4.5 h second row) MR-perfusion weighted imaging (MR-PWI) (CBV/CBF/MTT) at 5.25 h (third row) DWI at 24 h (fourth row) and follow-up DWI at 48 h (bottom). The CTP and MR-PWI demonstrate a mismatch between the CBV (no abnormality) and the CBF/MTT penumbra (arrows). After cessation of hypertensive therapy, the DWI abnormahty grows into the region predicted by the CBF/MTT maps...

Figure 14 HPLC separation of metabolites of 24,25-(OH)2D3 made in the perfused rat kidney. Extract of perfusate from kidneys perfused in the presence of 1250 nM 24,25-(0H)2-D3. (A) Absorbance at 265 vs. run time. (B) Absorbance vs. wavelength vs. run time. (A) and (B) represent the same chromatographic run. Note in (A) that the peak marked as an impurity appears minor because the wavelength used for monitoring is 265 nm. The impurity peak absorbs strongly at 225 run and in the 275- to 280-nm region. Note also that all metabohte peaks have the classical vitamin D absorption spectrum. Conditions Zorbax-SIL (6.2 mm X 25 cm) hexane-isopropanol-methanol (94/5/1) 1.5 mL/min. (From Ref. 121.)...

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