Effects of Iloprost on Oxygenation during One-Lung Ventilation in Patients with Low Diffusing Capacity for Carbon Monoxide: A Randomized Controlled Study

Abstract

The protective mechanism of hypoxic pulmonary vasoconstriction during one-lung ventilation (OLV) is impaired in patients with a low diffusing capacity for carbon monoxide (DLCO). We hypothesized that iloprost inhalation would improve oxygenation and lung mechanics in patients with low DLCO who underwent pulmonary resection. Forty patients with a DLCO < 75% were enrolled. Patients were allocated into either an iloprost group (ILO group) or a control group (n = 20 each), in which iloprost and saline were inhaled, respectively. The partial pressure of arterial oxygen/fraction of inspired oxygen (PaO2/FiO2) ratio, pulmonary shunt fraction, alveolar dead space, dynamic compliance, and hemodynamic parameters were assessed 20 min after the initiation of OLV and 20 min after drug administration. Repeated variables were analyzed using a linear mixed model between the groups. Data from 39 patients were analyzed. After iloprost inhalation, the ILO group exhibited a significant increase in the PaO2/FiO2 ratio and a decrease in alveolar dead space compared with the control group (p = 0.025 and p = 0.042, respectively). Pulmonary shunt, dynamic compliance, hemodynamic parameters, and short-term prognosis were comparable between the two groups. Selective iloprost administration during OLV reduced alveolar dead space and improved oxygenation while minimally affecting hemodynamics and short-term prognosis.

Effects of Iloprost on Arterial Oxygenation and Lung Mechanics during One-Lung Ventilation in Supine-Positioned Patients: A Randomized Controlled Study

“…Our results indicate that ILO positively affected alveolar ventilation in the supine position, which is consistent with the results of previous studies [ 9 , 10 ]. While the etCO 2 of the two groups remained unchanged since we adjusted the respiratory rate to maintain the parameter at its target range throughout the measurement periods, significant increases were observed in PaCO 2 of the control group, leading to an increase in the alveolar dead space.…”

“…Inhaled ILO selectively dilates pulmonary terminal capillaries surrounded by alveoli, resulting in increased pulmonary blood flow in the well-ventilated areas of the lung [ 12 ]. Hence, the effects of ILO were recently investigated by anesthesiologists as a potential rescue drug for hypoxia during OLV in thoracic surgery [ 8 , 9 , 10 ]. Indeed, previous studies indicated that the selective ILO administration to the ventilated lung during OLV induced a decrease in ventilation/perfusion (V/Q) mismatch and improved oxygenation [ 8 , 9 , 10 ].…”

“…Hence, the effects of ILO were recently investigated by anesthesiologists as a potential rescue drug for hypoxia during OLV in thoracic surgery [ 8 , 9 , 10 ]. Indeed, previous studies indicated that the selective ILO administration to the ventilated lung during OLV induced a decrease in ventilation/perfusion (V/Q) mismatch and improved oxygenation [ 8 , 9 , 10 ]. Yet these results were confined to patients who underwent pulmonary resection, which is performed in the lateral decubitus position.…”

“…Iloprost (ILO) is a prostacyclin analogue, and inhalation of the drug induces vasodilation in the well-ventilated areas of the lung with little effect on systemic circulation [ 7 ]. Hence, recent studies have investigated the capability of ILO as a potential rescue drug for hypoxia during OLV, and demonstrated that selective ILO nebulization to the ventilated lung improved arterial oxygenation and lung mechanics in pulmonary resections [ 8 , 9 , 10 ]. However, whether ILO would provide similar effects during OLV in the supine position is not known.…”

Comparison between Sugammadex and Neostigmine after Video-Assisted Thoracoscopic Surgery–Thymectomy in Patients with Myasthenia Gravis: A Single-Center Retrospective Exploratory Analysis

“…Radial artery catheterization was performed for continuous pressure monitoring, and 7 Fr central venous catheterization was applied. Anesthesia was maintained with an inhalation anesthetic agent (sevoflurane or desflurane) at a 0.9–1.2 age-adjusted minimal alveolar concentration, combined with a continuous intravenous infusion of remifentanil to target a bispectral index of 40–60 [ 21 , 22 ].…”