LACTATE CLEARANCE AS AN PROGNOSTIC INDICATOR FOR SURVIVAL IN POLYTRAUMA PATIENTS

1. LACTATE CLEARANCE AS AN PROGNOSTIC INDICATOR FOR SURVIVAL IN POLYTRAUMA PATIENTS DR.ASHWINI M SHAH. Post Graduate-2nd yr DNB Dept of Anesthesiology GANGA HOSPITAL COIMBATORE

2. Special thanks to • Dr.Ravindra Bhat Prof & HOD • Dr.J.Balavenkat • Senior consultant • Dr.Sekar • Senior consultant • Dr.Balasubramani Senior consultant & Intensivist Dr.Karunanidhi PhD,for statistical analysis

3. TRAUMA - disease of bleeding • Hemorrhage - leading cause of death following trauma • Traumatic hemorrhagic shockkills quickly

4. In hemorrhagic shock resuscitationaims at control of bleeding and replacement of lost blood with fluids. • Outcome depends on depth and duration of shock. • SHOCK- defined simply as inadequate tissue perfusion. • Uncompensated / overt shock • Compensated / occult hypoperfusion

5. Resuscitation aimed at normalising vital parameters have been shown to be inadequate. • In large number of patients especially young adults presence of occult hypoperfusion syndrome needs to be kept in mind. • In the presence of normal vital parameters there is persistence of tissue hypoperfusion which leads to MODS or death.

6. Identification of these patients and carrying on the resuscitation measures till certain metabolic endpoints are met with has reduced the mortality. • These parameters include: -serum lactate -base deficit -tissue oxygen saturation -sublingual CO2 saturation. Out of this lactate is used extensively.

7. Lactate is an end point of anaerobic metabolism. • Inability to clear lactate in the face of normal vital signs indicates persistance of hypoperfusion. • Continuing resuscitation measures till lactate is cleared has improved outcome in trauma.

8. Serum Lactate Estimation Serum lacate: Enzymatic determination with colorimetric method RANDOX, GANGA HOSP. LAB Lactate is measured in whole blood within 2 minutes.

9. OBJECTIVE OF STUDY This study determines whether lactate clearancewithin 24 hrs of arrival of polytrauma patients presenting with hypovolemic shockand ISS > 16(Injury Severity Scoring) correlates with the outcome.

10. Review of literature 1)Abramson D, Scalea TM, Hitchcock R, et al. Lactate clearance and survival following injury. J Trauma.1993;35:584Y591. 2)ToffalettiJ.Elevations in blood lactate: overview of use in critical care.Scand J Clin Lab Invest. 1996;56 (suppl 224):107-110 3) Weil MH,Afifi AA. Experimental and clinical studies on lactate & pyruvate as indicators of the severity of acte circulatory failure(shock).circulation. 1970;41:989-1001 4) MizockBA,Falk JL. Lactic acidosis in critical illness. Crit care Med.1992;20:80-95 5) Bakker,GrisP,CoffernilsM,etal.Serial blood lactate levels can predict the development of multiple organ failure following septic shock.

11. Patients and Methods Type of study : Retrospective analysis of a prospective study Number of cases: 67 cases Place of study: Ganga hospital, Coimbatore Period of study : May 2009 – May 2010

12. INCLUSIONCRITERIA: 1)Age > 14 years 2)Polytrauma cases with ISS > 16 3)Hypovolemic shock with heart rate > 100/min, systolic < 90 mmHg 4)Lactate level on arrival > 2.2 mmol/L

13. Data recorded Name , age Vital parameters on arrival Injury severity score Lab profiling Lactate on arrival,every 4 hr lactate,end of 24 hr lactate,lactate levels till it normalised. Patient’s outcome

14. Patient groups PATIENT GROUP n=67 SURVIVORS n=63 Non-survivors n=4

15. ANALYSIS OF DATA • Fisher exact testwas used to find the difference of mortality rate between two groups. • Odds ratiowas used to assess the risk of death pertaining to the level of lactate. • Independent t-test was used to find the difference between the mean lactate levels among the two groups.

16. FISHER EXACT TEST *Fisher exact test, P<0.05 is considered significant. Therefore there is a significant difference in mortality rate among the 2 groups.

17. ODDS RATIO #There is 11.5 (95% CI is 1.1 – 120.2) times higher chances of death when lactate level remains more than 2.2 mmol/L after 24 hrs.

18. INDEPENDENT t-TEST * Independent –t test, P<0.001 is considered as significant

19. MEAN LACTATE LEVELS

20. Box plot

21. RESULTS 67 PATIENTS 16 patients did not clear lactate within 24 hrs 51 patients cleared lactate within 24 hrs 13 patients survived 3 patients died 50 patients survived 1 patient died

22. RESULTS • 3/16 (18.7%) patients who did not clear lactate within 24 hrs died compared to 1/51 (1.9%) death among who cleared lactate within 24 hrs (p=0.04) • There is 11.5 times higher chances of risk of death associated with those who have serum lactate clearance > 2.2 mmol/L after 24 hrs • The level of serum lactate is significantly lesser among the survivors compared to those died (p<0.001)

23. DISCUSSION • Lactate is a useful marker & early indicator of perfusion deficit. • One of the goals of resuscitation is to pay back the O2 debt that occurred during the period of shock. • Early clearance of this O2 debt improves survival in multiple injured patients.

24. When lactate has not cleared within 24 hrs: -on going hemorrhage -inadequate resuscitation -myocardial depression

25. Conclusion • Lactate clearance is be a good marker to evaluate the prognosis of the patient • Lactate clearance is statistically a better prognostic indicator than on arrival lactate level. • However, these findings needs further confirmation with more number of subjects

26. Thank you