Pressure-controlled inverse ratio ventilation improves gas exchange in obese children undergoing laparoscopic surgery: a randomized controlled study

Yanfeng Gong; Lin Liu; Wangping Zhang

Pressure-controlled inverse ratio ventilation improves gas exchange in obese children undergoing laparoscopic surgery: a randomized controlled study

Am J Transl Res. 2023 Nov 15;15(11):6551-6557. eCollection 2023.

Authors

Yanfeng Gong¹, Lin Liu², Wangping Zhang²

Affiliations

¹ Department of Anesthesiology, The People's Hospital of Chizhou Chizhou 247000, Aihui, China.
² Department of Anesthesiology, Women and Children's Hospital of Jiaxing Jiaxing 314000, Zhejiang, China.

PMID: 38074806
PMCID: PMC10703644

Abstract

Background: Obese children undergoing laparoscopic surgery frequently experience high end-tidal carbon dioxide partial pressure (P_ETCO₂) and respiratory acidosis. This study aimed to investigate the effects of pressure-controlled inverse ratio ventilation (IRV) with an inspiratory to expiratory ratio (I:E) of 1.5:1 on obese children undergoing laparoscopic surgery.

Methods: Eighty children undergoing laparoscopic surgery were randomly assigned to either the IRV group (I:E=1.5:1) or the control group (I:E=1:1.5). The lungs were mechanically ventilated following tracheal intubation. The children underwent pressure-controlled ventilation with an I:E ratio of 1.5:1 or 1:1.5. Respiratory mechanics, hemodynamic values, and ventilation-related side effects were recorded.

Results: Thirty minutes after establishing CO₂ pneumoperitoneum, the IRV group exhibited significantly higher tidal volume (Vt) and arterial partial pressure of oxygen (PaO₂) compared to the control group (97.6 ± 6.6 vs. 93.2 ± 8.0 ml, 283 ± 54 vs. 247 ± 40 mmHg, respectively) (P < 0.01). Furthermore, PaCO₂ was significantly lower in the IRV group than in the control group (41.4 ± 5.8 vs. 45.5 ± 5.7 mmHg, P=0.002). The incidence of intra-operative hypercapnia was significantly decreased in the IRV group (25% vs. 42.5%, P=0.03).

Conclusion: Pressure-controlled IRV can reduce the incidence of hypercapnia, increasing Vt, and thereby improving CO₂ elimination in obese children undergoing laparoscopy. This ventilation technique significantly improves gas exchange in this patient population. (Registration number: ChiCTR2000035589).

Keywords: Inverse ratio ventilation; gas exchange; hypercapnia; laparoscopy; obese children.