已经提出了不同的技术来测量肺实质内的抗生素水平;然而,它们的使用是有限的,因为它们是侵入性的,并与不良反应有关。我们探讨是否可以在从热湿交换过滤器(HMEFs)收集的呼出气冷凝液中测量β-内酰胺抗生素,并与支气管肺泡灌洗(BAL)测得的抗生素浓度相关。我们在接受机械通气的患者中设计了一项观察性研究,这需要BAL来确认或放弃肺炎的诊断。我们测量并关联了血浆中β-内酰胺抗生素的浓度,上皮衬液(ELF),和从HMEFs收集的呼气冷凝液。我们研究了12个病人,我们检测到血浆中存在抗生素,ELF,和每个患者的HMEFs研究。在所研究的人群中,抗生素的浓度非常异质。血浆中平均抗生素浓度为293.5(715)ng/mL,在ELF中12.3(31)ng/mL,和0.5(0.9)ng/mL的HMEF溶液。我们发现血浆中抗生素浓度与ELF之间没有显着相关性(R2=0.02,p=0.64),在血浆和HMEF之间(R2=0.02,p=0.63),或介于ELF和HMEF之间(R2=0.02,p=0.66)。我们得出的结论是,可以从机械通气患者HMEF中积聚的呼出气冷凝液中检测和测量β-内酰胺抗生素。然而,HMEF中的抗生素浓度与血浆或ELF之间均未观察到相关性.
Different techniques have been proposed to measure antibiotic levels within the lung parenchyma; however, their use is limited because they are invasive and associated with adverse effects. We explore whether beta-lactam antibiotics could be measured in exhaled breath condensate collected from heat and moisture exchange filters (HMEFs) and correlated with the concentration of antibiotics measured from bronchoalveolar lavage (BAL). We designed an observational study in patients undergoing mechanical ventilation, which required a BAL to confirm or discard the diagnosis of pneumonia. We measured and correlated the concentration of beta-lactam antibiotics in plasma, epithelial lining fluid (ELF), and exhaled breath condensate collected from HMEFs. We studied 12 patients, and we detected the presence of antibiotics in plasma, ELF, and HMEFs from every patient studied. The concentrations of antibiotics were very heterogeneous over the population studied. The mean antibiotic concentration was 293.5 (715) ng/mL in plasma, 12.3 (31) ng/mL in ELF, and 0.5 (0.9) ng/mL in
HMEF. We found no significant correlation between the concentration of antibiotics in plasma and ELF (R2 = 0.02, p = 0.64), between plasma and
HMEF (R2 = 0.02, p = 0.63), or between ELF and
HMEF (R2 = 0.02, p = 0.66). We conclude that beta-lactam antibiotics can be detected and measured from the exhaled breath condensate accumulated in the
HMEF from mechanically ventilated patients. However, no correlations were observed between the antibiotic concentrations in
HMEF with either plasma or ELF.