Metabolic Parameters Affecting Incidence Of Acquired Pneumonia And Length Of Hospital Stay In Intensive Care Unit Patients

Abstract

Background: Hospital-acquired pneumonia (HAP) is a major cause of morbidity and mortality in intensive care unit (ICU) patients. This study investigated the correlation between HAP incidence and metabolic parameters, including C-reactive protein (CRP), procalcitonin (PCT), blood glucose, lactate, and electrolyte levels.Methods: Data were collected from 100 ICU patients, including demographic information and clinical metrics such as ICU length of stay, duration of mechanical ventilation, and Oxygenation Index. Biochemical parameters, including CRP, PCT, blood glucose, lactate, and electrolytes, were measured using standard clinical protocols.Results: Among the participants, 45% developed HAP, while 55% did not. HAP incidence was positively correlated with ICU length of stay (r = 0.512, p < 0.001), duration of mechanical ventilation (r = 0.507, p < 0.001), and Oxygenation Index (r = 0.522, p < 0.001). Significant associations were also observed with CRP (r = 0.505, p < 0.001), PCT (r = 0.506, p < 0.001), blood glucose (r = 0.509, p < 0.001), lactate (r = 0.519, p < 0.001), and electrolyte levels (sodium: r = 0.518; potassium: r = 0.512; both p < 0.001).Discussion: The study findings indicate that 45% of participants developed acquired pneumonia during their ICU stay, while the remaining 55% did not. A moderate to strong positive correlation was observed between the length of ICU stay and the incidence of pneumonia (r = 0.512) and between the duration of mechanical ventilation and the onset of pneumonia (r = 0.507). These findings suggest that patients with longer ICU stays and extended mechanical ventilation are at an increased risk of developing pneumonia. Additionally, the Oxygenation Index was significantly correlated with pneumonia, though further details on this relationship were truncated in the document.

The mean age of the study cohort was 50.43 years, reflecting a population typically requiring ICU care due to chronic illnesses or acute medical events, such as infections or myocardial infarctions, as supported by Angus and Der Poll (2013) [12]. The balanced gender distribution minimizes bias and facilitates a more generalized understanding of ICU outcomes. Previous research by Wiencek and Winkelman (2010) suggests that gender differences can influence recovery trajectories, with females sometimes experiencing distinct complications due to hormonal factors [13]. The mean BMI of 24.36 kg/m² indicates that most participants were of normal weight, though the cohort likely included individuals who were either underweight or obese. According to Akinnusi et al. (2008) [14], both obesity and underweight status have been associated with poorer ICU outcomes, with obesity linked to longer ventilation periods and higher infection rates due to impaired immune function. Consequently, BMI remains essential in predicting ICU outcomes and guiding patient management.

Smoking status and educational background varied among participants, ensuring broad representation in the study. Smoking is a well-established risk factor for respiratory complications, making it particularly relevant for critically ill ICU patients. Smokers, as noted by Vincent et al. (2014) [15], are more susceptible to respiratory infections, such as chronic obstructive pulmonary disease (COPD), which can complicate ICU care and increase the risk of pneumonia. The variability in the length of ICU stays (mean = 5.98 days) reflects the severity of illness and recovery trajectories among participants. Kollef (1993) demonstrated that longer ICU stays are often associated with increased complications, such as infections and muscle wasting [16], and higher healthcare costs. Therefore, effectively managing ICU stay durations is crucial for improving patient outcomes and reducing resource utilization.

The mean duration of mechanical ventilation was 4.81 days, underscoring the need for individualized ventilatory strategies and timely weaning protocols to minimize complications like VAP, as highlighted by Vincent and Moreno (2010) [17]. Ranieri et al. (2018) further explained that prolonged mechanical ventilation increases the risk of lung injury, and difficulties in weaning can further complicate patient recovery [18]. Implementing structured weaning protocols reduces ventilation duration and improves patient outcomes.

The study's focus on clinical biomarkers such as CRP, PCT, and the Oxygenation Index provides valuable insights into ICU patients' inflammatory and infection status. A Bakker et al. (2013) study demonstrated that elevated CRP and PCT levels indicate significant inflammatory responses and potential bacterial infections commonly observed in critically ill patients [19]. These biomarkers are crucial for guiding treatment decisions, such as antibiotic therapy, and monitoring the disorder's progression [20].Implication: Several limitations should be noted in this study. First, a clear causative relationship could not be established, as the reported effect size between variables was measured using the correlation coefficient. Second, the study was conducted at a single setting, El-Kasr El-Einy Teaching Hospital, which may limit the generalizability of the findings, as different hospitals with more advanced ICU equipment may report varying parameters. The study included only 100 participants, which may restrict the ability to draw strong conclusions and generalize the results.