Ballók Bence, Schranc Álmos, Tóth Ibolya, Somogyi Petra, Tolnai József, Peták Ferenc, Fodor Gergely H
Department of Medical Physics and Informatics, Albert Szent-Györgyi Medical School, University of Szeged, Szeged, Hungary.
Unit for Anaesthesiological Investigations, Department of Anaesthesiology, Pharmacology, Intensive Care, and Emergency Medicine, University of Geneva, Geneva, Switzerland.
Front Physiol. 2023 Sep 18;14:1249127. doi: 10.3389/fphys.2023.1249127. eCollection 2023.
Respiratory parameters in experimental animals are often characterised under general anaesthesia. However, anaesthesia regimes may alter the functional and mechanical properties of the respiratory system. While most anaesthesia regimes have been shown to affect the respiratory system, the effects of general anaesthesia protocols commonly used in animal models on lung function have not been systematically compared. The present study comprised 40 male Sprague-Dawley rats divided into five groups ( = 8 in each) according to anaesthesia regime applied: intravenous (iv) Na-pentobarbital, intraperitoneal (ip) ketamine-xylazine, iv propofol-fentanyl, inhaled sevoflurane, and ip urethane. All drugs were administered at commonly used doses. End-expiratory lung volume (EELV), airway resistance (Raw) and tissue mechanics were measured in addition to arterial blood gas parameters during mechanical ventilation while maintaining positive end-expiratory pressure (PEEP) values of 0, 3, and 6 cm HO. Respiratory mechanics were also measured during iv methacholine (MCh) challenges to assess bronchial responsiveness. While PEEP influenced baseline respiratory mechanics, EELV and blood gas parameters ( < 0.001), no between-group differences were observed ( > 0.10). Conversely, significantly lower doses of MCh were required to achieve the same elevation in Raw under ketamine-xylazine anaesthesia compared to the other groups. In the most frequent rodent model of respiratory disorders, no differences in baseline respiratory mechanics or function were observed between commonly used anaesthesia regimes. Bronchial hyperresponsiveness in response to ketamine-xylazine anaesthesia should be considered when designing experiments using this regime. The findings of the present study indicate commonly used anaesthetic regimes allow fair comparison of respiratory mechanics in experimental animals undergoing any of the examined anaesthesia protocols.
实验动物的呼吸参数通常是在全身麻醉状态下进行表征的。然而，麻醉方案可能会改变呼吸系统的功能和力学特性。虽然大多数麻醉方案已被证明会影响呼吸系统，但动物模型中常用的全身麻醉方案对肺功能的影响尚未得到系统比较。本研究包括40只雄性Sprague-Dawley大鼠，根据所应用的麻醉方案分为五组（每组 = 8只）：静脉注射（iv）戊巴比妥钠、腹腔注射（ip）氯胺酮-赛拉嗪、静脉注射丙泊酚-芬太尼、吸入七氟醚和腹腔注射乌拉坦。所有药物均以常用剂量给药。在机械通气期间，除了测量动脉血气参数外，还测量呼气末肺容积（EELV）、气道阻力（Raw）和组织力学，同时维持呼气末正压（PEEP）值为0、3和6 cmH₂O。在静脉注射乙酰甲胆碱（MCh）激发试验期间也测量呼吸力学，以评估支气管反应性。虽然PEEP影响基线呼吸力学、EELV和血气参数（P < 0.001），但未观察到组间差异（P > 0.10）。相反，与其他组相比，在氯胺酮-赛拉嗪麻醉下，达到相同Raw升高所需的MCh剂量显著更低。在最常见的啮齿动物呼吸系统疾病模型中，常用麻醉方案之间在基线呼吸力学或功能方面未观察到差异。在设计使用该方案的实验时，应考虑氯胺酮-赛拉嗪麻醉引起的支气管高反应性。本研究结果表明，常用麻醉方案能够对接受任何一种所检查麻醉方案的实验动物的呼吸力学进行合理比较。
