Kollef M H, Ward S
Department of Internal Medicine, Pulmonary and Critical Care Medicine, Washington University School of Medicine, St. Louis, Mo 63110, USA.
Chest. 1998 Feb;113(2):412-20. doi: 10.1378/chest.113.2.412.
To determine the influence of mini-BAL culture results on subsequent changes in antibiotic therapy and patient outcomes.
Prospective, single-center, cohort study.
Medical ICU of Barnes-Jewish Hospital, St. Louis, a university-affiliated teaching hospital.
One hundred thirty mechanically ventilated patients undergoing mini-BAL for suspected ventilator-associated pneumonia (VAP).
Mini-BAL, prospective patient surveillance, and data collection.
Sixty (46.2%) patients had mini-BAL cultures that yielded at least one pathogen potentially accounting for the clinically suspected episode of VAP (64 bacterial, 3 viral, 2 fungal). Among the 60 patients with microbiologically positive mini-BAL cultures, 44 (73.3%) were classified as receiving inadequate antibiotic therapy (ie, identification of a microorganism resistant to the prescribed antibiotic regimen). Prior antibiotic administration or its absence remained unchanged in 51 (39.2%) patients based on the mini-BAL culture results, while in another 51 (39.2%) patients, antibiotic therapy was either begun (n=7) or the existing antibiotic regimen was changed (n=44), and in the remaining 28 (21.6%) patients, antibiotic therapy was discontinued altogether. The hospital mortality rates of these three groups were statistically different: 33.3%, 60.8%, and 14.3%, respectively (p<0.001). The most common pattern of antibiotic resistance resulting in an antibiotic change following mini-BAL was the identification of a Gram-negative bacteria resistant to a prescribed third-generation cephalosporin in 23 of 44 (52.3%) patients. Twenty-one of these 23 patients (91.3%) received prior therapy with a cephalosporin class antibiotic during the same hospitalization. Having an immunocompromised state (adjusted odds ratio [OR]=2.45; 95% confidence interval, 1.56 to 3.85; p=0.047) and the presence of a pathogen in the mini-BAL culture resistant to the empirically prescribed antibiotic regimen (adjusted OR=3.28; 95% confidence interval, 2.12 to 5.06; p=0.006) were identified as risk factors independently associated with hospital mortality by logistic regression analysis.
These data suggest that antibiotic selection prior to obtaining the results of lower airway cultures is an important determinant of outcome for patients with suspected VAP. A delay in initiating adequate antibiotic therapy was associated with a greater mortality. Therefore, the initial selection of antibiotics for the empiric treatment of VAP should be broad enough to cover all likely pathogens, including antibiotic-resistant bacteria. This appears to be especially important in patients having received prior antibiotics.
确定小型支气管肺泡灌洗（mini - BAL）培养结果对后续抗生素治疗变化及患者预后的影响。
前瞻性、单中心队列研究。
圣路易斯巴恩斯 - 犹太医院的医学重症监护病房，一所大学附属医院。
130例因疑似呼吸机相关性肺炎（VAP）接受小型支气管肺泡灌洗的机械通气患者。
小型支气管肺泡灌洗、前瞻性患者监测和数据收集。
60例（46.2%）患者的小型支气管肺泡灌洗培养至少检出一种可能导致临床疑似VAP发作的病原体（64例细菌、3例病毒、2例真菌）。在60例小型支气管肺泡灌洗培养微生物学阳性的患者中，44例（73.3%）被归类为接受了不充分的抗生素治疗（即鉴定出对规定抗生素方案耐药的微生物）。基于小型支气管肺泡灌洗培养结果，51例（39.2%）患者先前的抗生素使用情况保持不变，而在另外51例（39.2%）患者中，开始使用抗生素（n = 7）或改变现有抗生素方案（n = 44），其余28例（21.6%）患者则完全停止使用抗生素。这三组患者的医院死亡率在统计学上存在差异：分别为33.3%、60.8%和14.3%（p < 0.001）。小型支气管肺泡灌洗后导致抗生素改变的最常见耐药模式是在44例患者中的23例（52.3%）鉴定出对规定的第三代头孢菌素耐药的革兰氏阴性菌。这23例患者中有21例（91.3%）在同一住院期间接受过头孢菌素类抗生素的先前治疗。经逻辑回归分析，免疫功能低下状态（调整比值比[OR]=2.45；95%置信区间，1.56至3.85；p = 0.047）以及小型支气管肺泡灌洗培养中存在对经验性规定抗生素方案耐药的病原体（调整OR = 3.28；95%置信区间，2.12至5.06；p = 0.006）被确定为与医院死亡率独立相关的危险因素。
这些数据表明，在获得下呼吸道培养结果之前选择抗生素是疑似VAP患者预后的重要决定因素。开始充分抗生素治疗的延迟与更高的死亡率相关。因此，用于VAP经验性治疗的初始抗生素选择应足够广泛，以覆盖所有可能的病原体，包括耐药菌。这在接受过先前抗生素治疗的患者中似乎尤为重要。
