Blood ammonia and lactate levels on hospital arrival as a predictive biomarker in patients with out-of-hospital cardiac arrest



      No reliable predictor for the prognosis of out-of-hospital cardiac arrest (OHCA) on arrival at hospital has been identified so far. We speculate that ammonia and lactate may predict patient outcome.


      This is a prospective observational study. Non-traumatic OHCA patients who gained sustained return of spontaneous circulation and were admitted to acute care unit were included. Blood ammonia and lactate levels were measured on arrival at hospital. The patients were classified into two groups: ‘favourable outcome’ group (Cerebral Performance Category CPC1–2 at 6-months’ follow-up) and ‘poor outcome’ group (CPC3–5). Basal characteristics obtained from the Utstein template and biomarker levels were compared between these two outcome groups. Independent predictors were selected from all candidates using logistic regression analysis.


      A total of 98 patients were included. Ammonia and lactate levels in the favourable outcome group (n = 10) were significantly lower than those in poor outcome group (n = 88) (p < 0.05, respectively). On receiver operating characteristic analysis, the optimal cut-off value for predicting favourable outcome was determined as 170 μg dl−1 of ammonia and 12.0 mmol l−1 of lactate (area under the curve; 0.714 and 0.735, respectively). Logistic regression analysis identified ammonia (≤170 μg dl−1), therapeutic hypothermia and witnessed by emergency medical service personnel as independent predictors of favourable outcome. When both these biomarker levels were over threshold, positive predictive value (PPV) for poor outcome was calculated as 100%.


      Blood ammonia and lactate levels on arrival are independent prognostic factors for OHCA. PPV with the combination of these biomarkers predicting poor outcome is high enough to be useful in clinical settings.


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        • Rea T.D.
        • Eisenberg M.S.
        • Sinibaldi G.
        • White R.D.
        Incidence of EMS-treated out-of-hospital cardiac arrest in the United States.
        Resuscitation. 2004; 63: 17-24
        • Cummins R.O.
        • Chamberlain D.A.
        • Abramson N.S.
        • et al.
        Recommended guidelines for uniform reporting of data from out-of-hospital cardiac arrest: the Utstein Style. A statement for health professionals from a task force of the American Heart Association, the European Resuscitation Council, the Heart and Stroke Foundation of Canada, and the Australian Resuscitation Council.
        Circulation. 1991; 84: 960-975
        • Jacobs I.
        • Nadkarni V.
        • Bahr J.
        • et al.
        Cardiac arrest and cardiopulmonary resuscitation outcome reports: update and simplification of the Utstein templates for resuscitation registries: a statement for healthcare professionals from a task force of the International Liaison Committee on Resuscitation (American Heart Association, European Resuscitation Council, Australian Resuscitation Council, New Zealand Resuscitation Council, Heart and Stroke Foundation of Canada, InterAmerican Heart Foundation, Resuscitation Councils of Southern Africa).
        Circulation. 2004; 110: 3385-3397
        • Eisenberg M.
        • Hallstrom A.
        • Bergner L.
        The ACLS score. Predicting survival from out-of-hospital cardiac arrest.
        JAMA. 1981; 246: 50-52
        • Kellermann A.L.
        • Hackman B.B.
        • Somes G.
        Predicting the outcome of unsuccessful prehospital advanced cardiac life support.
        JAMA. 1993; 270: 1433-1436
        • Becker L.B.
        • Han B.H.
        • Meyer P.M.
        • et al.
        Racial differences in the incidence of cardiac arrest and subsequent survival. The CPR Chicago Project.
        N Engl J Med. 1993; 329: 600-606
        • Ralston S.H.
        • Voorhees W.D.
        • Showen L.
        • Schmitz P.
        • Kougias C.
        • Tacker W.A.
        Venous and arterial blood gases during and after cardiopulmonary resuscitation in dogs.
        Am J Emerg Med. 1985; 3: 132-136
        • Carden D.L.
        • Martin G.B.
        • Nowak R.M.
        • Foreback C.C.
        • Tomlanovich M.C.
        Lactic acidosis during closed-chest CPR in dogs.
        Ann Emerg Med. 1987; 16: 1317-1320
        • Mullner M.
        • Sterz F.
        • Domanovits H.
        • Behringer W.
        • Binder M.
        • Laggner A.N.
        The association between blood lactate concentration on admission, duration of cardiac arrest, and functional neurological recovery in patients resuscitated from ventricular fibrillation.
        Intensive Care Med. 1997; 23: 1138-1143
        • Prause G.
        • Ratzenhofer-Comenda B.
        • Smolle-Juttner F.
        • et al.
        Comparison of lactate or BE during out-of-hospital cardiac arrest to determine metabolic acidosis.
        Resuscitation. 2001; 51: 297-300
        • Adrie C.
        • Cariou A.
        • Mourvillier B.
        • et al.
        Predicting survival with good neurological recovery at hospital admission after successful resuscitation of out-of-hospital cardiac arrest: the OHCA score.
        Eur Heart J. 2006; 27: 2840-2845
        • Donnino M.W.
        • Miller J.
        • Goyal N.
        • et al.
        Effective lactate clearance is associated with improved outcome in post-cardiac arrest patients.
        Resuscitation. 2007; 75: 229-234
        • Yanagawa Y.
        • Sakamoto T.
        • Sato H.
        Relationship between laboratory findings and the outcome of cardiopulmonary arrest.
        Am J Emerg Med. 2009; 27: 308-312
      1. 2005 American Heart Association Guidelines for Cardiopulmonary Resuscitation and Emergency Cardiovascular Care.
        Circulation. 2005; 112: IV1-211
        • Akaike H.
        A new look at the statistical model identification.
        IEEE Trans Autom Control. 1974; 19: 716-723
        • Schwarz G.
        Estimating the dimension of a model.
        Ann Stat. 1978; 6: 461-464
        • Hosmer D.W.
        • Hosmer T.
        • Le Cessie S.
        • Lemeshow S.
        A comparison of goodness-of-fit tests for the logistic regression model.
        Stat Med. 1997; 16: 965-980
        • Kasai A.
        • Nagao K.
        • Kikushima K.
        • et al.
        Ammonia as a marker of neurological outcomes in patients with out-of hospital cardiac arrest [abstract].
        Circ J. 2008; 72: 685
        • Bakker J.
        • Jansen T.C.
        Don’t take vitals, take a lactate.
        Intensive Care Med. 2007; 33: 1863-1865
        • Sheps D.S.
        • Conde C.
        • Cameron B.
        • et al.
        Resting peripheral blood lactate elevation in survivors of prehospital cardiac arrest: correlation with hemodynamic, electrophysiologic and oxyhemoglobin dissociation indexes.
        Am J Cardiol. 1979; 44: 1276-1282
        • Atkinson D.E.
        • Bourke E.
        Metabolic aspects of the regulation of systemic pH.
        Am J Physiol. 1987; 252: F947-F956
        • Kekomaki M.
        • Louhimo I.
        Blood ammonium concentration during hemorrhagic shock in the rabbit.
        Acta Chir Scand. 1971; 137: 745-748
        • Sakaguchi Y.
        • Yuge K.
        • Yoshino M.
        • Yamashita F.
        • Hashimoto T.
        Hyperammonemia in the neonate with hypoxia.
        Adv Exp Med Biol. 1982; 153: 147-152
        • Lowenstein J.M.
        Ammonia production in muscle and other tissues: the purine nucleotide cycle.
        Physiol Rev. 1972; 52: 382-414
        • Friedmann B.
        • Frese F.
        • Menold E.
        • Bartsch P.
        Effects of acute moderate hypoxia on anaerobic capacity in endurance-trained runners.
        Eur J Appl Physiol. 2007; 101: 67-73
        • Kato T.
        • Matsumura Y.
        • Tsukanaka A.
        • Harada T.
        • Kosaka M.
        • Matsui N.
        Effect of low oxygen inhalation on changes in blood pH, lactate, and ammonia due to exercise.
        Eur J Appl Physiol. 2004; 91: 296-302