Damiani Elisa, Casarotta Erika, Carsetti Andrea, Mariotti Giulia, Vannicola Sara, Giorgetti Rachele, Domizi Roberta, Scorcella Claudia, Adrario Erica, Donati Abele
Department of Biomedical Sciences and Public Health, Università Politecnica delle Marche, Ancona, Italy.
Anesthesia and Intensive Care Unit, Azienda Ospedaliera Universitaria "Ospedali Riuniti Umberto I-Lancisi-Salesi", Ancona, Italy.
Front Med (Lausanne). 2022 Jul 28;9:957773. doi: 10.3389/fmed.2022.957773. eCollection 2022.
In COVID-19 patients requiring mechanical ventilation, the administration of high oxygen (O) doses for prolonged time periods may be necessary. Although life-saving in most cases, O may exert deleterious effects if administered in excessive concentrations. We aimed to describe the prevalence of hyperoxemia and excessive O administration in mechanically ventilated patients with SARS-CoV-2 pneumonia and determine whether hyperoxemia is associated with mortality in the Intensive Care Unit (ICU) or the onset of ventilator-associated pneumonia (VAP).
Retrospective single-center study on adult patients with SARS-CoV-2 pneumonia requiring invasive mechanical ventilation for ≥48 h. Patients undergoing extracorporeal respiratory support were excluded. We calculated the excess O administered based on the ideal arterial O tension (PaO) target of 55-80 mmHg. We defined hyperoxemia as PaO > 100 mmHg and hyperoxia + hyperoxemia as an inspired O fraction (FiO) > 60% + PaO > 100 mmHg. Risk factors for ICU-mortality and VAP were assessed through multivariate analyses.
One hundred thirty-four patients were included. For each day of mechanical ventilation, each patient received a median excess O of 1,121 [829-1,449] L. Hyperoxemia was found in 38 [27-55]% of arterial blood gases, hyperoxia + hyperoxemia in 11 [5-18]% of cases. The FiO was not reduced in 69 [62-76]% of cases of hyperoxemia. Adjustments were made more frequently with higher PaO or initial FiO levels. ICU-mortality was 32%. VAP was diagnosed in 48.5% of patients. Hyperoxemia (OR 1.300 95% CI [1.097-1.542]), time of exposure to hyperoxemia (OR 2.758 [1.406-5.411]), hyperoxia + hyperoxemia (OR 1.144 [1.008-1.298]), and daily excess O (OR 1.003 [1.001-1.005]) were associated with higher risk for ICU-mortality, independently of age, Sequential Organ failure Assessment score at ICU-admission and mean PaO/FiO. Hyperoxemia (OR 1.033 [1.006-1.061]), time of exposure to hyperoxemia (OR 1.108 [1.018-1.206]), hyperoxia + hyperoxemia (OR 1.038 [1.003-1.075]), and daily excess O (OR 1.001 [1.000-1.001]) were identified as risk factors for VAP, independently of body mass index, blood transfusions, days of neuromuscular blocking agents (before VAP), prolonged prone positioning and mean PaO/FiO before VAP.
Excess O administration and hyperoxemia were common in mechanically ventilated patients with SARS-CoV-2 pneumonia. The exposure to hyperoxemia may be associated with ICU-mortality and greater risk for VAP.
在需要机械通气的新冠肺炎患者中，可能需要长时间给予高剂量氧气（O）。尽管在大多数情况下可挽救生命，但如果给予过高浓度的氧气，可能会产生有害影响。我们旨在描述严重急性呼吸综合征冠状病毒2（SARS-CoV-2）肺炎机械通气患者中高氧血症和过量吸氧的发生率，并确定高氧血症是否与重症监护病房（ICU）死亡率或呼吸机相关性肺炎（VAP）的发生有关。
对需要有创机械通气≥48小时的成年SARS-CoV-2肺炎患者进行回顾性单中心研究。排除接受体外呼吸支持的患者。我们根据55-80mmHg的理想动脉血氧分压（PaO）目标计算过量吸氧情况。我们将高氧血症定义为PaO>100mmHg，将高氧+高氧血症定义为吸入氧分数（FiO）>60%+PaO>100mmHg。通过多变量分析评估ICU死亡率和VAP的危险因素。
共纳入134例患者。在机械通气的每一天，每位患者接受的过量氧气中位数为1121[829-1449]L。在38[27-55]%的动脉血气中发现高氧血症，在11[5-18]%的病例中发现高氧+高氧血症。在69[62-76]%的高氧血症病例中FiO未降低。随着PaO或初始FiO水平升高，调整频率更高。ICU死亡率为32%。48.5%的患者被诊断为VAP。高氧血症（比值比[OR]1.300，95%置信区间[CI][1.097-1.542]）、高氧血症暴露时间（OR 2.758[1.406-5.411]）、高氧+高氧血症（OR 1.144[1.008-1.298]）和每日过量吸氧（OR 1.003[第1.001-1.005]）与ICU死亡风险较高相关，独立于年龄、ICU入院时的序贯器官衰竭评估评分和平均PaO/FiO。高氧血症（OR 1.033[1.006-1.061]）、高氧血症暴露时间（OR 1.108[1.018-1.206]）高氧+高氧血症（OR 1.038[1.003-1.075]）和每日过量吸氧（OR 1.001[1.000-1.001]）被确定为VAP的危险因素，独立于体重指数、输血、VAP发生前神经肌肉阻滞剂使用天数、长时间俯卧位和VAP发生前的平均PaO/FiO。
在SARS-CoV-2肺炎机械通气患者中，过量吸氧和高氧血症很常见。高氧血症暴露可能与ICU死亡率和VAP风险增加有关。
