Effect of residual leaning force on intrathoracic pressure during mechanical ventilation in children

Abstract

Aim Determine the effect of residual leaning force on intrathoracic pressure (ITP) in healthy children receiving mechanical ventilation. We hypothesized that application of significant residual leaning force (2.5 kg or 20% of subject body weight) would be associated with a clinically important change in ITP. Methods IRB-approved pilot study of healthy, anesthetized, paralyzed mechanically ventilated children (6 months to 7 years). Peak endotracheal pressure (ETP), a surrogate of ITP, was continuously measured before and during serial incremental increases in sternal force from 10% to 25% of the subject’s body weight. A delta ETP of ≥2.0 cmH2O was considered clinically significant. Results 13 healthy, anesthetized, paralyzed mechanically ventilated children (age: 26 ± 24 m, range: 6.5–87 m; weight: 13 ± 5 kg, range: 7.4–24.8 kg) were enrolled. Peak ETP increased from baseline for all force applications (10% body weight: mean difference of 0.8 cmH2O, p < 0.01; 15% body weight: mean difference of 1.1 cmH2O, p < 0.01; 20% body weight: mean difference of 1.5 cmH2O, p < 0.01; 25% body weight: mean difference of 1.89 cmH2O, p < 0.01). Residual leaning force of ≥2.5 kg was associated with a 2.0 cmH2O change in peak ETP (odds ratio 7.5; CI95 1.5–37.7; p = 0.014) while sternal force ≥20% body weight was not (odds ratio 2.4; CI95 0.6–9.2; p = 0.2). Conclusion In healthy anesthetized children, changes in ETP were detectable at residual leaning forces as low as 10% of subject body weight. Residual leaning force of 2.5 kg was associated with increases in ETP ≥2.0 cmH2O.

Cardiopulmonary Resuscitation Quality: Improving Cardiac Resuscitation Outcomes Both Inside and Outside the Hospital

“…46 Although data are sparse regarding outcomes related to leaning, animal studies have shown that leaning increases right atrial pressure and decreases cerebral and coronary perfusion pressure, cardiac index, and left ventricular myocardial flow. [46][47][48] Human studies show that a majority of rescuers often lean during CPR and do not allow the chest to recoil fully. 49,50 Therefore, the expert panel agrees that leaning should be minimized.…”

Chest compression release velocity: Association with survival and favorable neurologic outcome after out-of-hospital cardiac arrest

“…Two human studies have implicated incomplete chest wall recoil as negatively impacting hemodynamics, but were not performed on cardiac arrest patients. 37,38 Observational studies describe a lack of complete chest wall recoil, also referred to as leaning, during resuscitation from both OHCA and in-hospital cardiac arrest. 6,17,29,30 To our knowledge, there are no clinical data demonstrating an association between complete chest recoil and outcomes.…”

Do chest compressions during simulated infant CPR comply with international recommendations?

“…Incomplete chest release during CPR has been observed to generate increased intrathoracic pressures during the chest release phase, consequently limiting the return of venous blood to the heart and reducing coronary and cerebral perfusion pressures 15 27–29. While incomplete release during CPR in older paediatric subjects has been observed in 25–50% of chest compressions,22 30 >97% of chest compressions achieved target release forces during CPR in adults 19.…”

“…Chest compression depth and compression rate targets were based on ERC and UKRC guideline recommendations: targeting depths of ‘at least one-third’ the external anterior–posterior (AP) chest diameter (≥36.7 mm for this manikin model) and a rate between 100 and 120 compressions/min 6 7. A chest release force target of <2.5 kg was defined to represent the residual chest compression force associated with a clinically significant increase in intrathoracic pressure in infants 15. Finally, a duty cycle target of 30–50% was defined to represent the most effective duty cycle range observed in infant animal surrogates 16–18.…”