Comparison of mechanical power between PCV vs VCV in children undergoing laparoscopic surgery under general anesthesia.

Pressure-limited mode’s adaptability to compliance changes: PCV delivers breaths at a set pressure, adjusting the tidal volume based on the lung’s compliance. In laparoscopic surgeries where pneumoperitoneum affects compliance due to increased intra-abdominal pressure, PCV might result in lower mechanical power as it adapts to these compliance changes more dynamically than VCV.

Tidal volume variability: VCV delivers a set tidal volume regardless of changes in lung compliance, potentially leading to higher delivered tidal volumes in situations with decreased lung compliance (as in laparoscopic surgeries with pneumoperitoneum). This could result in increased mechanical power in VCV due to higher tidal volumes against less compliant lungs.

Peak airway pressures: In laparoscopic surgeries, increased intra-abdominal pressure from insufflation of carbon dioxide can increase peak airway pressures. PCV, by limiting pressure, might lead to lower peak airway pressures compared to VCV. Lower peak pressures might contribute to reduced lung injury risk and subsequently lower mechanical power in PCV.

Intrinsic PEEP: VCV might generate higher intrinsic Positive End-Expiratory Pressure (PEEP) due to its fixed tidal volume delivery, especially in conditions like laparoscopic surgeries where dynamic changes in compliance occur. This increased PEEP can contribute to higher mechanical power compared to PCV, which may have lower or more adjustable PEEP levels.

Optimal distribution of ventilation: PCV may facilitate better distribution of ventilation in conditions like laparoscopic surgeries where there might be compromised lung compliance due to altered positioning, such as Trendelenburg or reverse Trendelenburg positions. Improved ventilation distribution might reduce the need for higher pressures, thus lowering mechanical power.

Respiratory system mechanics and energy expenditure: By adapting to changes in lung compliance, PCV might be more efficient in reducing energy expenditure and mechanical work on the respiratory system compared to VCV, particularly in conditions of altered lung mechanics during laparoscopic surgery.

These rationales suggest that PCV might offer advantages in adapting to changing compliance, providing more stable pressures, and potentially reducing mechanical power compared to VCV in the context of laparoscopic surgeries in pediatric patients. However, empirical research through controlled trials or retrospective studies comparing these ventilation modes in this specific surgical setting is necessary to validate these hypotheses.