Markers of Oxidative Stress and Clinical Outcome in Critically ill Septic Patients: A Preliminary Study from North India

Abstract

Introduction: Sepsis is the leading cause of mortality in non-coronary Intensive Care Units (ICUs). Oxidative stress is one of the important features in pathogenesis of sepsis.

Aim: This study was undertaken to evaluate levels of oxidants and antioxidants in patients with sepsis admitted to ICU.

Study design: This was a non-interventional clinical case-control study undertaken at a tertiary level teaching hospital in New Delhi, India.

Materials and methods: Forty-six consecutive non-pediatric patients admitted to ICU with sepsis were included and subjected to detailed history, physical examination and investigations. Blood samples were drawn to evaluate oxidant Malondialdehyde (MDA) and antioxidant (alpha-tocopherol) levels. Acute Physiology and Chronic Health Evaluation II (APACHE II) and Organ Dysfunction and/or Infection (ODIN) scores were calculated and patients followed up for outcomes. Twenty age and sex matched healthy subjects served as controls.

Results: Mean levels of malondialdehyde were higher in patients than controls (17.2±3.8nm/ml versus 4.6±1.6nm/ml, p<0.001) while levels of alpha-tocopherol were lower (3.2±1.3μg/ml versus 9.9±2.0μg/ml, p<0.001). The mean APACHE II and ODIN scores were 18.1±9.3 and 1.7±1.3 respectively in patients. These scores were two to three fold higher in non survivor patients (n=22) in comparison with survivors (n=18) (p<0.001). There was no significant difference between the two groups in oxidants and antioxidants levels (p>0.05). However, a significant and positive correlation was observed between oxidant -antioxidant levels and APACHE II, ODIN and International Normalized Ratio (INR) scores in septic patients overall.

Conclusion: The oxidants in septic patients were significantly higher while antioxidants were significantly lower than healthy controls. There was also a significant correlation with APACHE II and ODIN scores. A large patient population based study may draw more specific conclusions.

Keywords: APACHE II; Antioxidants; ICU; Oxidants; Sepsis.