Title: A Cross Sectonal Observational Study of Prognostic Value of Veno-Arterial Carbon Dioxide Difference in Septic Shock Patients in ICU
Authors: Dr Kambhampati S L N Sunanda Kameswari, Dr A.Satyanarayana, MD
DOI: https://dx.doi.org/10.18535/jmscr/v8i2.63
Abstract
Background and Aim: Early identification of tissue hypoperfusion helps in decreasing mortality due to septic shock. This tissue hypoperfusion not only occurs due to decreased perfusion pressures due to hypotension, caused by reduced cardiac output (CO), but also due to the abnormal regional distribution of blood flow.Metabolic variables like central venous oxygen saturation(scvo2), serum lactate are established markers of tissue hypoperfusion. Recently, the central venous-to-arterial carbon dioxide difference (v-a)CO2 has been proposed as an alternative marker of tissue hypoperfusion.So we deigned this study aiming to know the porognostic value of venous-to-arterial carbon dioxide difference in septic shock.
Materials and Methods: Patients ,admitted in ICU,satisfying the criteria of septic shock were studied. Arterial blood gas,central venous samples are obtained, on admission ,6h,12h,24h.sixty patients were studied.Patients were classified into survivors and nonsurvivors. venous-to-arterial carbon dioxide difference difference and serum were evaluated and correlated to outcome.
Results: The mean Veno-arterial carbon dioxide difference in Survivors at the time of admission (T0), 6 hours after admission (T6), 12 hours after admission (T12), 24 hours after admission (T24), was 7.23+1.41, 5.8+0.87, 5.71+0.80, 5.52+0.82 mmHg respectively and in Non-survivors was 8.51+1.31, 9.4+0.88, 9.84+1.01, 9.78+0.78 mmHg respectively with a statistically significant difference between survivors and Non-survivors(P<0.05). The mean serum lactate in Survivors at the T0, T6, T12, T24 was 7.74+1.54, 5.70+1.29, 3.9+1.18, 2.45+1.09 mmol/l respectively and in Non-survivors was 8.69+2.08, 9.09+1.58, 8.94+1.34, 8.79+1.33 mmol/l respectively. There was no significant statistical difference at the time of admission T0(p>0.05), and a statistically significant difference was observed at T6, T12, T24(p<0.05). The lactate clearance at the end of 6hours in survivors and non-survivors was 26% and 11%, and at the end of 24 hours was 68% and 16%, respectively. A positive correlation between veno-arterial carbon dioxide difference and serum lactate was also observed at T0,T6, T12, T24.
Conclusion: veno-arterial carbon dioxide difference can be used as markers of prognosis in septic shock and it has a positive correlation with serum lactate.
