Authors: Vladimír Sobota, Martin Müller, Karel Roubík

Citation

Sobota V, Müller M, Roubík K. Intravenous administration of normal saline may be misinterpreted as a change of end-expiratory lung volume when using electrical impedance tomography. Scientific Reports. 2019 Apr 8;9(1):5775.

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Published in Scientific Reports (Nature).

Abstract

Electrical impedance tomography (EIT) is a noninvasive imaging modality that allows real-time monitoring of regional lung ventilation. The aim of the study is to investigate whether fast saline infusion causes changes in lung impedance that could affect the interpretation of EIT data. Eleven pigs were anaesthetized and mechanically ventilated. A bolus of 500 mL of normal saline was administered rapidly. Two PEEP steps were performed to allow quantification of the effect of normal saline on lung impedance. The mean change of end-expiratory lung impedance (EELI) caused by the saline bolus was equivalent to a virtual decrease of end-expiratory lung volume (EELV) by 227 (188–250) mL and decremental PEEP step of 4.40 (3.95–4.59) cmH2O (median and interquartile range). In contrast to the changes of PEEP, the administration of normal saline did not cause any significant differences in measured EELV, regional distribution of lung ventilation determined by EIT or in extravascular lung water and intrathoracic blood volume. In conclusion, EELI can be affected by the changes of EELV as well as by the administration of normal saline. These two phenomena can be distinguished by analysis of regional distribution of lung ventilation.

References

1.          Frerichs, I. et al. Chest electrical impedance tomography examination, data analysis, terminology, clinical use and recommendations: consensus statement of the Translational EIT development study group. Thorax. 72, 83-93 (2017).

2.          Wrigge, H. et al. Electrical impedance tomography compared with thoracic computed tomography during a slow inflation maneuver in experimental models of lung injury. Crit. Care Med. 36, 903–909 (2008).

3.          Wolf, G.K. et al. Reversal of dependent lung collapse predicts response to lung recruitment in children with early acute lung injury. Pediatr. Crit. Care Med. 13, 509–515 (2012).

4.          Muders, T. et al. Tidal recruitment assessed by electrical impedance tomography and computed tomography in a porcine model of lung injury. Crit. Care Med. 40, 903–911 (2012).

5.          Odenstedt, H. et al. Slow moderate pressure recruitment maneuver minimizes negative circulatory and lung mechanic side effects: evaluation of recruitment maneuvers using electric impedance tomography. Intensive Care Med. 31, 1706–1714 (2005).

6.          Lowhagen, K., Lindgren, S., Odenstedt, H., Stenqvist, O. & Lundin, S. Prolonged moderate pressure recruitment manoeuvre results in lower optimal positive end-expiratory pressure and plateau pressure. Acta Anaesthesiol. Scand. 55, 175–184 (2011).

7.          Erlandsson, K., Odenstedt, H., Lundin, S. & Stenqvist O. Positive end-expiratory pressure optimization using electric impedance tomography in morbidly obese patients during laparoscopic gastric bypass surgery. Acta Anaesthesiol. Scand. 50, 833–9 (2006).

8.          Becher, T.H. et al. Assessment of respiratory system compliance with electrical impedance tomography using a positive end-expiratory pressure wave maneuver during pressure support ventilation: a pilot clinical study. Crit. Care. 18, 679 (2014).

9.          Blankman, P., Hasan, D., Erik, G.J. & Gommers, D. Detection of the ‘best’ positive end-expiratory pressure derived from electrical impedance tomography parameters during a decremental positive end-expiratory pressure trial. Crit. Care. 18, R95 (2014).

10.       Kushner, R.F. & Schoeller, D.A. Estimation of total body water by bioelectrical impedance analysis. Am. Journal Clin. Nutr. 44, 417–424 (1986).

11.       Tang, W., Ridout, D. & Modi, N. Assessment of total body water using bioelectrical impedance analysis in neonates receiving intensive care. Arch. Dis. Child Fetal Neonatal. Ed. 77, F123–F126 (1997).

12.       Sadleir, R.J. & Fox, R.A. Detection and quantification of intraperitoneal fluid using electrical impedance tomography. IEEE Trans. Biomed. Eng. 48, 484–491 (2001).

13.       Tucker, A.S., Ross, E.A., Paugh-Miller, J. & Sadleir, R.J. In vivo quantification of accumulating abdominal fluid using an electrical impedance tomography hemiarray. Physiol. Meas. 32, 151–165 (2011).

14.       Noble, T.J., Harris, N.D., Morice, A.H., Milnes, P. & Brown, B.H. Diuretic induced change in lung water assessed by electrical impedance tomography. Physiol. Meas. 21, 155–163 (2000).

15.       Bodenstein, M. et al. Influence of crystalloid and colloid fluid infusion and blood withdrawal on pulmonary bioimpedance in an animal model of mechanical ventilation. Physiol Meas. 33, 1225–1236 (2012).

16.       Laghi, F. & Tobin, M. J. Indications for mechanical ventilation in Principles and practice of mechanical ventilation (ed. Tobin M. J.) 115 (The McGraw-Hill Companies, Inc., 2013).

17.       Frerichs, I. et al. Regional lung perfusion as determined by electrical impedance tomography in comparison with electron beam CT Imaging. IEEE Trans. Med. Imaging. 18, 6 (2002).

18.       Rhodes, A. et al. Surviving sepsis campaign: international guidelines for management of severe sepsis and septic shock: 2016. Intensive Care Med. 43, 304–377 (2017).

19.       Frerichs, I. et al. Patient examinations using electrical impedance tomography – sources of interference in the intensive care unit. Physiol. Meas. 32, L1-10 (2011).

20.       Costa, E.L.V. et al. Bedside estimation of recruitable alveolar collapse and hyperdistension by electrical impedance tomography. Intensive Care Med. 35, 1132-1137 (2009).

21.       Karsten, J., Grusnick, C., Paarmann, H., Heringlake, M. & Heinze, H. Positive end-expiratory pressure titration at bedside using electrical impedance tomography in post-operative cardiac surgery patients. Acta Anaesthesiol. Scand. 59, 723-732 (2015).

22.       Bikker, I.G., Leonhardt, S., Bakker, J. & Gommers, D. Lung volume calculated from electrical impedance tomography in ICU patients at different PEEP levels. Intensive Care Med. 35, 1362-7 (2009).

23.       Grivans, C., Lundin, S., Stenquist, O. & Lindgren, S. Positive end-expiratory pressure-induced changes in end-expiratory lung volume measured by spirometry and electric impedance tomography. Acta Anaesthesiol. Scand. 55, 1068–1077 (2011).

24.       Markhorst, D.G., Groeneveld, A.B., Heethaar R. M., Zonneveld, E. & van Genderingen, H.R. Assessing effects of PEEP and global expiratory lung volume on regional electrical impedance tomography. J. Med. Eng. Technol. 33, 281-287 (2009).

25.       Trepte, C.J.C. et al. Electrical impedance tomography (EIT) for quantification of pulmonary edema in acute lung injury. Crit. Care. 20:18, (2016).

26.       Otáhal, M., Mlček, M., Vítková, I. & Kittnar, O. A novel experimental model of acute respiratory distress syndrome in pig. Physiol. Res. 65, S643-S651 (2016).

27.       Pomprapa, A. et al. Automatic protective ventilation using the ARDSNet protocol with the additional monitoring of electrical impedance tomography. Crit. Care. 18, R128 (2014).

28.       Suchomel, J. & Sobota, V. A model of end-expiratory lung impedance dependency on total extracellular body water. J. Phys.: Conf. Ser. 434, 012011 (2013).