To evaluate the effect of ulinastatin on pulmonary function during laparoscopic cholecystectomy (LC) for elderly patients with mild pulmonary dysfunction.

A total of 65 to 75 years old 100 patients with mild obstructive ventilation dysfunction undergoing elective LC were randomly divided into a control group (group C) and an ulinastatin group (group UTI), with 50 cases in each group. Group UTI were intravenously infused with ulinastatin 0.5×10⁴ U/kg 30 min before incision, and group C with the equal volume of normal saline. The airway peak pressure (Ppeak), mean airway pressure (Pmean), airway plateau pressure (Pplat), and positive end-expiratory pressure (PEEP) were measured 5 min after intubation (before pneumoperitoneum) (T₁), at the end of pneumoperjtoneum (T₂), and 10 min after the end of pneumoperitoneum (T₃). The driving pressure was calculated. Arterial blood samples were obtained at T_l, T₂, and T3 for blood gas analysis, and the PaO₂ and PaCO₂ were recorded. The alveolar-arterial oxygen partial pressure difference (A-aDO₂), oxygenation index (PaO₂/FiO₂), respiratory index (RI), and physiologic dead space fraction (VD/VT) were calculated. The time to remove tracheal tube and the occurrence of complications such as hypercapnia, hypoxemia, and new lung vocalization within 48 hours after extubation were recorded.

The Ppeak, Pmean, DP, RI, VD/VT, and A-aDO₂, as well as the incidences of hypoxemia and new lung snoring within 48 h, were lower, the PaO₂/FiO₂ was higher, and the postoperative extubation time was shorter in group UTI than in group C (all P<0.05). Compared with those at T₁ and T₃, the Ppeak, Pmean, DP, RI, VD/VT, and A-aDO₂ at T₁ were higher and the PaO₂/FiO₂ was lower in both groups (all P<0.05).

Ulinastatin can improve pulmonary function during laparoscopic surgery in elderly patients with mild obstructive ventilation dysfunction.

Ulinastatin; Protective lung ventilation strategy; Laparoscopic surgery; Respiratory