The aim of this study was to assess the normal values of the Smith-Madigan inotropy index (SMII) and oxygen delivery index (DO2I) in low-birth-weight (LBW) and very-low-birth-weight (VLBW) newborns on the first 3 days of life, and to identify how different degrees of maturity influence cardiovascular alterations during the transitional period compared with term neonates.
Twenty-eight VLBW newborns, 46 LBW newborns and 50 normal full-term newborns admitted to our department were studied. Hemodynamics of the left heart were measured in all neonates over the first 3 days using the Ultrasonic Cardiac Output Monitor (USCOM). This was combined with hemoglobin concentration and pulse oximetry to calculate DO2I. Blood pressure was combined with the hemodynamic measures and hemoglobin concentration to calculate SMII.
SMII showed statistically significant differences among the three groups (VLBW 0.48 ± 0.11; LBW 0.54 ± 0.13; term 0.69 ± 0.17 W/m2 P < 0.001), which was in line with the following myocardial parameters: stroke volume index (SVI) and cardiac index (CI) (P < 0.001 and <0.001). For systemic oxygen delivery (DO2) parameters, significant differences were found for DO2I (P < 0.001) while hemoglobin concentration and pulse oximetry demonstrated no significant differences. In the VLBW group, SMII and DO2I showed no significant change over the 3 days.
Normal inotropy and systemic DO2I values in VLBW neonates over the first 3 days of life were assessed. SMII and DO2I were significantly lower in VLBW neonates during the first 72 h of life. With increasing birth weight, higher myocardial inotropy and DO2 were found. The addition of USCOM examination to standard neonatal echocardiography may provide further important information regarding cardiac function.
de Boode WP. Cardiac output monitoring in newborns. Early Hum Dev 2010;86:143–8.
Rivers E, Nguyen B, Havstad S, Ressler J, Muzzin A, Knoblich B, et al. Early goal-directed therapy in the treatment of severe sepsis and septic shock. N Engl J Med 2001;345:1368–77.
de Oliveira CF, de Oliveira DS, Gottschald AF, Moura JD, Costa GA, Ventura AC, et al. ACCM/PALS haemodynamic support guidelines for paediatric septic shock: an outcomes comparison with and without monitoring central venous oxygen saturation. Intensive Care Med 2008;34:1065–75.
Martin J, Shekerdemian LS. The monitoring of venous saturations of oxygen in children with congenitally malformed hearts. Cardiol Young 2009;19:34–9.
Shepherd SJ, Pearse RM. Role of central and mixed venous oxygen saturation measurement in perioperative care. Anesthesiology 2009;111:649–56.
Ranucci M, Isgrò G, De La Torre T, Romitti F, De Benedetti D, et al. Continuous monitoring of central venous oxygen saturation (Pediasat) in pediatric patients undergoing cardiac surgery: a validation study of a new technology. J Cardiothorac Vasc Anesth 2008;22:847–52.
Phillips RA, Paradisis M, Evans N, Southwell D, Burstow D, West M. Validation of 2D independent CW Doppler measurements in preterm neonates by comparison with echocardiography. Heart Lung Circ 2006;15S:S50.
Meyer S, Todd D, Shadboldt B. Assessment of portable continuous wave Doppler ultrasound (Ultrasonic Cardiac Output Monitor) for cardiac output measurements in neonates. J Paediatr Child Health 2009;45:464–8.
Patel N, Dodsworth M, Mills JF. Cardiac output measurement in newborn infants using the Ultrasonic Cardiac Output Monitor: an assessment of agreement with conventional echocardiography, repeatability and new user experience. Arch Dis Child Fetal Neonatal Ed 2011;96:F206–11.
He SR, Zhang C, Liu YM, Sun YX, Zhuang J, Chen JM, et al. Accuracy of the Ultrasonic Cardiac Output Monitor in healthy term neonates during postnatal circulatory adaptation. Chin Med J (Engl) 2011;124:2284–9.
Zheng ML, Sun X, Zhong J, He SR, Pan W, Pang CC, et al. Clinical study of neonatal cardiac output measurement methods. Zhonghua Er Ke Za Zhi 2013;51:58–63.
He SR, Sun X, Zhang C, Jian Z, Sun YX, Zheng ML, et al. Measurement of systemic oxygen delivery and inotropy in healthy term neonates with the Ultrasonic Cardiac Output Monitor (USCOM). Early Hum Dev 2013;89:289–94.
Nidorf SM, Picard MH, Triulzi MO, Thomas JD, Newell J, King ME, et al. New perspectives in the assessment of cardiac chamber dimensions during development and adulthood. J Am Coll Cardiol 1992;19:983–8.
Guyton AC, Lindsey AW, Kaufmann BN. Effect of mean circulatory filling pressure and other peripheral circulatory factors on cardiac output. Am J Phys 1955;180:463–8.
Dannevig I, Dale HC, Liestol K, Lindemann R. Blood pressure in the neonate: three non-invasive oscillometric pressure monitors compared with invasively measured blood pressure. Acta Paediatr 2005;94:191–6.
Nuntnarumit P, Yang W, Bada-Ellzey HS. Blood pressure measurements in the newborn. Clin Perinatol 1999;26:981–96.
Smith BE, Madigan VM. Non-invasive method for rapid bedside estimation of inotropy: theory and preliminary clinical validation. Br J Anaesth 2013;111:580–8.
Phillips RA, Smith BE, Madigan VM. Stroke volume monitoring: novel continuous wave Doppler parameters, algorithms and advanced noninvasive haemodynamic concepts. Curr Anesthesiol Rep 2017;7:387–98.
Zanotti-Cavazzoni SL, Hollenberg SM. Cardiac dysfunction in severe sepsis and septic shock. Curr Opin Crit Care 2009;15:392–7.
Rowland DG, Gutgesell HP. Noninvasive assessment of myocardial contractility, preload, and afterload in healthy newborn infants. Am J Cardiol 1995;75:818–21.
Bryant RM, Shirley RL, Ott DA, Feltes TF. Left ventricular performance following the arterial switch operation: use of noninvasive wall stress analysis in the postoperative period. Crit Care Med 1998;26:926–32.
Kishkurno S, Takahashi Y, Harada K, Ishida A, Tamura M, Takada G. Postnatal changes in left ventricular volume and contractility in healthy term infants. Pediatr Cardiol 1997;18:91–5.
Porter TR, Shillcutt SK, Adams MS, Desjardins G, Glas KE, Olson JJ, et al. Guidelines for the use of echocardiography as a monitor for therapeutic intervention in adults: a report from the American Society of Echocardiography. J Am Soc Echocardiogr 2015;28:40–56.
Negrine RJ, Chikermane A, Wright JG, Ewer AK. Assessment of myocardial function in neonates using tissue Doppler imaging. Arch Dis Child Fetal Neonatal Ed 2012;97:F304–6.
Ciccone MM, Scicchitano P, Zito A, Gesualdo M, Sassara M, Calderoni G, et al. Different functional cardiac characteristics observed in term/preterm neonates by echocardiography and tissue Doppler imaging. Early Hum Dev 2011;87:555–8.
Gardiner HM, Pasquini L, Wolfenden J, Barlow A, Li W, Kulinskaya E, et al. Myocardial tissue Doppler and long axis function in the fetal heart. Int J Cardiol 2006;113:39–47.
Anderson PA. The heart and development. Semin Perinatol 1996;20:482–509.
Corresponding author: Prof. Shao-Ru He, PhD, The Second School of Clinical Medicine, Southern Medical University, Guangzhou, P.R. China; and Department of Pediatrics, Guangdong Academy of Medical Sciences, Guangdong Provincial People’s Hospital, Guangzhou, P.R. China
The Journal of Perinatal Medicine is a truly international forum covering the entire field of perinatal medicine. It is an essential news source for all those obstetricians, neonatologists, perinatologists and allied health professionals who wish to keep abreast of progress in perinatal and related research.
01 Jan 1973
Eduardo Bancalari, Joseph Chappelle, Frank A. Chervenak, Vincenzo D'Addario, Mehmet R. Genc, Anne Greenough, Amos Grunebaum, Justin C. Konje, Asim Kurjak M.D., Roberto Romero and Ivica Zalud, MD PhD