Tidal Volume Requirement in Mechanically Ventilated Infants with Meconium Aspiration Syndrome

Abstract

Objective The aim of the study is to test the hypothesis that increased physiologic dead space and functional residual capacity seen in meconium aspiration syndrome (MAS) results in higher tidal volume (V_T) requirement to achieve adequate ventilation.

Study Design Retrospective review of infants with MAS admitted to our hospital from 2000 to 2010 managed with conventional ventilation. Demographics, ventilator settings, V_T, respiratory rate (RR), and blood gas values were recorded. Minute ventilation (MV) was calculated as RR × V_T. Only V_T values with corresponding partial pressure of carbon dioxide (Paco ₂) between 35 and 60 mm Hg were included. Mean V_T/kg and MV/kg were calculated for each patient. Forty infants ventilated for lung disease other than MAS or pulmonary hypoplasia served as controls.

Results Birth weights of the 28 MAS patients and 40 control infants were similar (3,330 ± 500 g and 3,300 ± 640 g). Two patients in each group required extracorporeal membrane oxygenation. Infants with MAS required 26% higher V_T and 42% higher MV compared with controls to maintain equal Paco ₂.

Conclusion Infants with MAS require larger V_T and higher total MV to achieve similar alveolar ventilation, consistent with pathophysiology of MAS. Our findings provide the first reference data to guide selection of V_T in infants with MAS.

Keywords

meconium aspiration syndrome - tidal volume - minute ventilation - mechanical ventilation

• References

• 1 Gelfand SL, Fanaroff JM, Walsh MC. Controversies in the treatment of meconium aspiration syndrome. Clin Perinatol 2004; 31 (3) 445-452
• 2 Goldsmith JP. Continuous positive airway pressure and conventional mechanical ventilation in the treatment of meconium aspiration syndrome. J Perinatol 2008; 28 (Suppl. 03) S49-S55
• 3 Tyler DC, Murphy J, Cheney FW. Mechanical and chemical damage to lung tissue caused by meconium aspiration. Pediatrics 1978; 62 (4) 454-459
• 4 Tran N, Lowe C, Sivieri EM, Shaffer TH. Sequential effects of acute meconium obstruction on pulmonary function. Pediatr Res 1980; 14 (1) 34-38
• 5 Yeh TF, Lilien LD, Barathi A, Pildes RS. Lung volume, dynamic lung compliance, and blood gases during the first 3 days of postnatal life in infants with meconium aspiration syndrome. Crit Care Med 1982; 10 (9) 588-592
• 6 Davey AM, Becker JD, Davis JM. Meconium aspiration syndrome: physiological and inflammatory changes in a newborn piglet model. Pediatr Pulmonol 1993; 16 (2) 101-108
• 7 Dreyfuss D, Saumon G. Ventilator-induced lung injury: lessons from experimental studies. Am J Respir Crit Care Med 1998; 157 (1) 294-323
• 8 Keszler M. State of the art in conventional mechanical ventilation. J Perinatol 2009; 29 (4) 262-275
• 9 Keszler M, Abubakar K. Volume guarantee: stability of tidal volume and incidence of hypocarbia. Pediatr Pulmonol 2004; 38 (3) 240-245
• 10 Lista G, Castoldi F, Fontana P , et al. Lung inflammation in preterm infants with respiratory distress syndrome: effects of ventilation with different tidal volumes. Pediatr Pulmonol 2006; 41 (4) 357-363
• 11 Dawson C, Davies MW. Volume-targeted ventilation and arterial carbon dioxide in neonates. J Paediatr Child Health 2005; 41 (9-10) 518-521
• 12 Nassabeh-Montazami S, Abubakar KM, Keszler M. The impact of instrumental dead-space in volume-targeted ventilation of the extremely low birth weight (ELBW) infant. Pediatr Pulmonol 2009; 44 (2) 128-133
• 13 van Kaam AH, Haitsma JJ, De Jaegere A, van Aalderen WM, Kok JH, Lachmann B. Open lung ventilation improves gas exchange and attenuates secondary lung injury in a piglet model of meconium aspiration. Crit Care Med 2004; 32 (2) 443-449
• 14 Clark RH, Yoder BA, Sell MS. Prospective, randomized comparison of high-frequency oscillation and conventional ventilation in candidates for extracorporeal membrane oxygenation. J Pediatr 1994; 124 (3) 447-454