Abstract
Objective
To quantify the hemodynamic effects of turning critically ill, mechanically ventilated patients to the extreme left and right lateral postures.
Design
Prospective investigation.
Setting
Eight-bed intensive care unit in a university hospital.
Patients
Twelve consecutive patients presenting with severe respiratory failure and requiring continuous positive inotropic support.
Interventions
All patients were mechanically ventilated and placed in a kinetic treatment system. They were positioned in the supine, left dependent, and right dependent postures, resting for 15 min in each position.
Measurements and results
Hemodynamic measurements, assessments of right ventricular function, and determinations of intrathoracic blood volume were performed in three different positions. Concentrations of atrial natriuretic peptide in plasma were quantified. In three patients, the findings were controlled by transesophageal echocardiography.
Cardiac index [median (range) 5.5 (3.2–8.1) vs 4.3 (3.2–7.5) l/min per m2,p<0.01], intrathoracic blood volume [1125 (820–1394) vs 1037 (821–1267) ml/m2,p<0.01], and right ventricular end-diastolic volume [130 (83–159) vs 114 (79–155) ml/m2,p<0.05] increased significantly in the left dependent position compared to supine. Mean arterial pressure did not change. Atrial natriuretic peptide levels rose from 140 to 203 pg/ml. In the right dependent position, we found a marked decrease in the mean arterial pressure [85 mmHg (supine) to 72 mmHg (right dependent),p<0.01]. Cardiac index and intrathoracic blood volume were unchanged, but right ventricular enddiastolic volume decreased from 114 to 102 ml/m2 (p<0.05) Additionally, atrial natriuretic peptide levels decreased significantly (median Δ value: 37 pg/ml). In echocardiographic controls we found an increase in right ventricular end-diastolic diameters in the left dependent position and shortened diameters in the right dependent position.
Conclusions
Extreme lateral posture affects the cardiovascular system in critically ill, mechanically ventilated patients: in the left dependent position a “hyperdynamic state” is reinforced, while the right decubitus position impairs right ventricular preload and predisposes to hypotension. Echocardiography and changes in plasma atrial natriuretic peptide values indicate that these findings are due to altered distensibility of the right ventricle caused by regional intrathoracic gravitational changes. We conclude that the duration and the angle of lateral posture should be restricted in hemodynamically unstable patients.
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References
Pappert D, Rossaint R, Slama K, Grüning T, Falke KJ (1994) Influence of positioning on ventilation—perfusion relationships in severe adult respiratory distress syndrome. Chest 106:1511–1516
Lamm WE, Graham MM, Albert RK (1994) Mechanism by which the prone position improves oxygenation in acute lung injury. Am J Respir Crit Care Med 150:184–193
deBoisblanc BP, Castro M, Everret B, Grender J, Walker CD, Summer W (1993) Effect of air-supported, continuous, postural oscillation on the risk of early ICU pneumonia in nontraumatic critical illness. Chest 103:1543–1547
Sahn SA (1991) Continuous lateral rotational therapy and nosocomial pneumonia. Chest 99:1263–1267
Fink MP, Helsmoortel CM, Stein KL, Lee PC, Cohn SM (1990) The efficacy of an oscillating bed in the prevention of lower respiratory tract infection in critically ill victims of blunt trauma. Chest 97:132–137
Summer WR, Curry P, Haponik EF, Nelson S, Elston R (1989) Continuous mechanical turning of intensive care unit patients shortens length of stay in some diagnostic-releated groups. J Crit Care 4:45–53
Nelson LD, Anderson H (1989) Physiologic effects of steep positioning in the surgical intensive care unit. Arch Surg 124:352–355
Bein Th, Metz Ch, Fröhlich D, Vescia F, Taeger K (1994) Changes in intrathoracic blood volume and right ventricular function during continuous axial rotation (kinetic therapy) (abstract). Clin Intensive Care 5[Suppl 4]:M 48.1
Murray JF, Matthay MA, Luce JM, Flick FR (1988) An expanded definition of the adult respiratory distress syndrome. Am J Resp Crit Care Med 138:720–723
Knaus WA, Draper EA, Wagner DP, Zimmerman JE (1985) APACHE-II: a severity of disease classification system. Crit Care Med 13:818–829
Lemeshow S, Teres D, Pastides H (1985) A method for predicting survival and mortality of ICU patients using objectively derived weights. Crit Care Med 13:519–525
Garner JS, Jarvis WR, Emori TG (1988) CDC definitions for nosocomial infections. Am J Infect Control 16:128–140
Vincent JL, Bihari D (1992) Sepsis, severe sepsis or sepsis syndrome: need for clarification. Intensive Care Med 18:255–257
Lichtwark-Aschoff M, Zeravik J, Pfeiffer UJ (1992) Intrathoracic blood volume accuraterly reflects circulatory volume status in critically ill patients with mechanical ventilation. Intensive Care Med 18:142–147
Needleman P, Greenwald JE (1986) Atriopeptin: a cardiac hormone intimately involved in fluid, electrolyte, and blood pressure homeostasis. N Engl J Med 314:828–834
Hartter E, Woluszuk W, Stummvoll HK (1986) Radioimmunoassay of atrial natriuretic peptides in human plasma. Clin Chem 32:441–445
Safcsak K, Nelson LD (1994) Thermodilution right ventricular ejection fraction measurements: room temperature versus cold temperature injectate. Crit Care Med 22:1136–1141
Hedenstierna G (1992) What value does the recording of intrathoracic blood volume have in clinical practice? Intensive Care Med 18:137–138
Redl G, Germann P, Plattner H, Hammerle A (1993) Right ventricular function in early septic shock states. Intensive Care Med 19:3–7
Abel FL (1989) Myocardial function in sepsis and endotoxin shock. Am J Physiol 257:R 1265-R 1281
Maruyama Y, Nunokawa T, Koiwa T (1983) Mechanical interdependence between the ventricles. Basis Res Cardiol 78:544–547
Kennedy GT, Bryant A, Crawford MH (1984) The effects of lateral body positioning on measurements of pulmonary artery and pulmonary artery wedge pressures. Heart Lung 13:155–158
Santamare WP, Shaffer T, Hughes D (1986) A theoretical and experimental model of ventricular interdependence. Basic Res Cardiol 81:529–535
Santamare WP, Hickman JL, Bove AA (1984) Right an left ventricular pressure-volume response to respiratory maneuvers. J Appl Physiol 57:1520–1528
Whitman GR, Howaniak DL, Verga TS (1982) Comparison of cardiac output measurements in 20-degree right and left lateral recumbent positions. Heart Lung 11:256–257
Nakao S, Come PC, Miller MJ, Momomura S, Sahagian P, Ransil P, Grossman W (1986) Effects of supine and lateral positions on cardiac output and intracardiac pressures: an experimental study. Circulation 73:579–585
Shippy CR, Appel RL, Shoemaker WC (1984) Reliability of clinical monitoring to assess blood volume in critically ill patients. Crit Care Med 12:107–112
Bar-Yishay E, Hyatt RE, Rodarte JR (1986) Effects of heart weight on distribution of lung surface pressures in vertical dogs. J Appl Physiol 61:712–718
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Bein, T., Metz, C., Keyl, C. et al. Effects of extreme lateral posture on hemodynamics and plasma atrial natriuretic peptide levels in critically ill patients. Intensive Care Med 22, 651–655 (1996). https://doi.org/10.1007/BF01709741
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DOI: https://doi.org/10.1007/BF01709741