Effects of Parenteral Protein Concentrations in Critically Ill Patients in ICU: A Comparative Study

Background: Parenteral protein supplements can prevent deterioration of acute critical illness during admission at intensive care unit (ICU). This study aimed to evaluate the effect of parenteral proteins on ICU outcome and to compare the effect of two different protein concentrations on handgrip strength in critically ill patients. Materials and Methods: This prospective comparative study included 60 acute critically ill patients who had parenteral nutrition during their ICU stay. The patients were divided into two groups: a standard protein group who received protein concentration of 1 g/kg/day (group A) and a high-protein group who received protein concentration of 2 g/kg/day (group B). The nutrition was delivered through a central line and the separate bottles technique. Results: Nitrogen balance was more negative in group B compared to group A within the first 3 days. The handgrip strength on day 7 was significantly higher in group B than group A. The forearm thickness, quadriceps muscle thickness, and overall muscle thickness were significantly higher in group B on day 7. The durations of mechanical ventilation, ICU stay, and total hospital stay were not significantly different between both groups. The protein dose was not significantly associated with the overall 2-month mortality. Conclusion: High parenteral protein intake (2 g/kg/day) associated with better handgrip strength and significant improvement of muscle thickness at the end of the 1st week of follow-up. Studies with larger sample size and longer durations of follow-up are recommended.