Perioperative Medicine and Intensive Care, Karolinska University Hospital, Stockholm, Sweden.
Section for Anesthesiology and Intensive Care Medicine, Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden.
Br J Anaesth. 2017 Apr 1;118(4):610-617. doi: 10.1093/bja/aex036.
BACKGROUND.: Apnoeic oxygenation during anaesthesia has traditionally been limited by the rapid increase in carbon dioxide and subsequent decrease in pH. Using a Transnasal Humidified Rapid-Insufflation Ventilatory Exchange (THRIVE) technique a slower increase in carbon dioxide than earlier studies was seen. Notably, apnoeic oxygenation using THRIVE has not been systematically evaluated with arterial blood gases or in patients undergoing laryngeal surgery. The primary aim of this study was to characterize changes in arterial P O 2 , P CO 2 and pH during apnoeic oxygenation using THRIVE under general anaesthesia.
METHODS.: Adult patients, (ASA I-II), undergoing shorter laryngeal surgery under general anaesthesia, were oxygenated during apnoea using THRIVE, 100% oxygen, 40-70 litres min - 1 . A cohort was randomized to hyperventilate during pre-oxygenation. Vital parameters and blood gases were monitored.
RESULTS.: Thirty-one patients, age 51 (34-76) yr, BMI 25 (4) were included. Mean apnoea time was 22.5 (4.5) min. Patients were well oxygenated, S pO 2 was never below 91%. The increase in P aCO 2 and end-tidal CO 2 during apnoea was 0.24 (0.05) and 0.12 (0.04) kPa min -1 , respectively. Hyperventilation during pre-oxygenation generated no difference in P aCO 2 at the end of apnoea compared with normoventilation.
CONCLUSIONS.: This physiological study of apnoeic oxygenation using THRIVE during laryngeal surgery shows that this technique is able to keep patients with mild systemic disease and a BMI <30 well oxygenated for a period of up to 30 min. The THRIVE concept makes it possible to extend the apnoeic window but monitoring of CO 2 and/or pH is recommended.
CLINICAL TRIAL REGISTRATION.: NCT02706431.
在麻醉期间，传统的无通气氧合会受到二氧化碳快速增加和随后 pH 值下降的限制。使用经鼻加湿快速充气通气交换（THRIVE）技术，二氧化碳的增加速度比早期研究要慢。值得注意的是，THRIVE 技术在无通气氧合中的应用尚未通过动脉血气或在接受喉科手术的患者中进行系统评估。本研究的主要目的是在全身麻醉下使用 THRIVE 技术评估无通气氧合时动脉 P O 2 、P CO 2 和 pH 值的变化。
接受全身麻醉下短时间喉科手术的成年患者（ASA I-II 级），在无通气期间使用 THRIVE 技术进行 100%氧气通气，流量为 40-70 升/分钟。一组患者在预充氧期间被过度通气。监测生命体征和血气。
共纳入 31 例患者，年龄 51（34-76）岁，BMI 25（4）。平均无通气时间为 22.5（4.5）分钟。患者氧合良好，S pO 2 从未低于 91%。无通气期间 P aCO 2 和呼气末 CO 2 的增加分别为 0.24（0.05）和 0.12（0.04）kPa/min。预充氧期间过度通气与正常通气相比，无通气结束时的 P aCO 2 没有差异。
本研究在喉科手术中使用 THRIVE 进行无通气氧合的生理研究表明，该技术能够使轻度系统性疾病和 BMI<30 的患者在长达 30 分钟的时间内保持良好的氧合。THRIVE 概念使得延长无通气窗口成为可能，但建议监测 CO 2 和/或 pH 值。
NCT02706431。
