Mukhopadhyay Chiranjoy, Bhargava Anudita, Ayyagari Archana
Department of Microbiology, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow, India.
Indian J Med Res. 2003 Dec;118:229-35.
BACKGROUND & OBJECTIVES: Among hospital-acquired infections, pneumonia is considered to be the leading cause of death mainly in patients with mechanical ventilation in intensive care units (ICUs). The present study was undertaken to estimate the occurrence of hospital-acquired pneumonia (HAP) as well as ventilator-associated pneumonia (VAP) along with the effect of different variables and to detect the presence of multi drug resistant (MDR) organisms in the intensive care unit (ICU).
Of the 328 patients admitted in the ICU during 2001, 241 stayed for > 72 h and 148 were ventilated. The respiratory specimens collected from the cases and controls were sent for cytology, bacterial culture and antimicrobial sensitivity.
The overall rate of HAP was 53.9 per cent, mortality rate was 47.3 per cent and attributable risk of mortality with ventilator was 72.3 per cent. Occurrence of VAP was 81.7 per cent. The rate of acquisition of HAP increased along with the duration of stay in the ICU. Of the total bacterial isolates, 96.2 per cent were obtained from patients on ventilator, an overall preponderance of Gram-negative bacteria, commonest being Pseudomonas spp along with 16.3 per cent polymicrobial infection was found in ICU. A significant number of ICU isolates were MDR in comparison to those from the non-ICU settings.
INTERPRETATION & CONCLUSION: Mechanical ventilation and duration of ICU stay emerged as important risk factors for the development of HAP and VAP. MDR Gram-negative bacilli were the commonest respiratory pathogens responsible for increased mortality in patients with VAP.
在医院获得性感染中，肺炎被认为是主要导致重症监护病房（ICU）中机械通气患者死亡的首要原因。本研究旨在评估医院获得性肺炎（HAP）以及呼吸机相关性肺炎（VAP）的发生率，同时评估不同变量的影响，并检测重症监护病房（ICU）中多重耐药（MDR）微生物的存在情况。
2001年入住ICU的328例患者中，241例住院时间超过72小时，148例接受了机械通气。收集病例组和对照组的呼吸道标本，进行细胞学、细菌培养及药敏试验。
HAP的总体发生率为53.9%，死亡率为47.3%，呼吸机导致的可归因死亡风险为72.3%。VAP的发生率为81.7%。HAP的发生率随着在ICU住院时间的延长而增加。在所有分离出的细菌中，96.2%来自接受机械通气的患者，革兰氏阴性菌总体占优势，最常见的是假单胞菌属，同时在ICU中发现16.3%的患者存在混合感染。与非ICU环境中的分离株相比，ICU中有相当数量的分离株为多重耐药。
机械通气和在ICU的住院时间是发生HAP和VAP的重要危险因素。多重耐药革兰氏阴性杆菌是导致VAP患者死亡率增加的最常见呼吸道病原体。
