2007, Number 1
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Med Crit 2007; 21 (1)
Impedance spectroscopy
Beltrán VN, Cerón DU, Sánchez MG, Remolina SM, Sacristán RE
Language: Spanish
References: 22
Page: 21-25
PDF size: 67.30 Kb.
ABSTRACT
Impedance spectroscopy has been proponed as a method of monitoring mucosal injury due to ischemia and hypoperfusion in critically ill patients. The present study evaluates the gastric impedance difference between survivors and non survivors from some Intensive Care Units in Mexico City.
Impedance spectrometry probe and nasogastric tubes (ISP/NGT) were placed in 100 patients from 7 Intensive Care Units, to record impedance measurements for a maximum of 3 days. The difference between the impedance measurements and the normal values (obtained previously) was calculated for each patient during the first 12h of monitoring.
Analysis of Variance was used to compare the behavior between survivors and non survivors. The average impedance difference for survivors was 935.18 ± 52.26 Ω/h whereas non survivors had an average of 1675.53 ± 142 Ω/h (p ‹ 0.001). The results suggest a major level of tissue damage in death patients.
REFERENCES
Miller P. Threshold values of intramucosal pH and mucosal arterial CO2 gap during shock resuscitation. J Trauma 1998;45(5):868-872.
Schiedler M, Cutler B, Fiddian-Green R. Sigmoid intramural pH for prediction of ischemic colitis during aortic surgery. Arch Surg 1986;122:881-886.
Fiddian-Green R. Splanchnic ischemia and multiple organ failure in the critically ill». Ann Coll Surg 1988;70:128-134.
Haglund U, Bulkley G, Granger D. On the pathophysiology of intestinal ischemic injury. Acta Chir Scand 1987;153:321-324.
Doglio G, Pusajo J, Egurrola et al. Gastric mucosal pH as a prognostic index of mortality in critically ill patients. Crit Care Med 1991;19(8):1037-1040.
Gutiérrez G et al. Gastric intramucosal pH as a therapeutic index of tissue oxygenation in critically ill patients. Lancet 1992;338 (8787):195-199.
Shoemaker W, Apple P, Kran H et al. Prospective trials of supranormal values of survivors as therapeutic goals in high risk surgical patient. Chest 1998;94:1176-1186.
Gomersall CD, Joynt GM, Freebairn RC et al. Resuscitation of critically ill patients based on the results of gastric tonometry: a prospective randomized controlled trial. Crit Care Med 2000;28(3):607-614.
Heard S, Helsmoortel C, Kent J et al. Gastric tonometry in healthy volunteers: Effect of raditidine on calculated intramural pH. Crit Care Med 1991;19(2):271-274.
Gys T, Hubens A, Neels H et al. Prognostic value of gastric intramural pH in surgical intensive care patients. Crit Care Med 1988;16(12):1222-1224.
Fiddian-Green R, Baker S. Predictive value of the stomach wall for complications after cardiac operations: Comparison with other monitoring. Crit Care Med 1987;15(2):153-156.
Kyle AH, Chan CT, Minchinton AI. Characterization of three-dimensional tissue cultures using electrical impedance spectroscopy. Biophys J 1999;76:2640-2648.
Kun S, Peura RA. Selection of measurement frequencies for optimum extraction of tissue impedance model parameters. Med Biol Eng Comput 1999;37:699-703.
Gersing E. Impedance spectroscopy on living tissue for determination of the state of organs. Biolectrochem Bioenerg 1998;45:145-149.
Othman S, Sacristan E, Gonzalez C et al. In situ impedance spectroscopy of the intestinal mucosa in an ischemia-reperfusion model. 25th Annual IEEE-EMBS Conference, Cancun, Mexico, 2003.
González CA, Villanueva C, Othman S et al. Impedance spectroscopy for monitoring ischemic injury in the intestinal mucosa. Physiol Meas 2003;24(2):277-289.
Sacristan E, Amador R, Rodríguez A et al. Dual frequency coil and MRIS method for the characterization of Ischemic injury in the intestinal wall. 25th Annual IEEE-EMBS Conference, Cancun, Mexico, 2003.
Beltrán N, Sánchez-Miranda G, Godínez M, Díaz U, Sacristán E. Gastric impedance spectroscopy in cardiovascular surgery patients vs healthy volunteers. Proceedings of the 2005 IEEE-EMBS 27th Conference, Shanghai, China. 2005:2516-2519.
Beltrán N, Sánchez-Miranda G, Godínez M, Díaz U, Sacristán E. Gastric impedance spectroscopy in elective cardiovascular surgery patients. Physiol Meas 2006;27(3):265-277.
Othman S, Sacristan RE. Complex impedance spectrometer using parallel demodulation and digital conversion. US patent No. 6,970,783, 2005.
Sacristan RE. Impedance spectroscopy method for monitoring ischemic mucosal damage in hollow viscous organs. US patent No. 6,965,795, 2005.
Sacristan RE. Impedance spectroscopy system and catheter for ischemic mucosal damage monitoring in hollow viscous organs. US patent No. 6,882,879, 2005.