What are the types of Lactic Acidosis?
Type A Lactic Acidosis occurs when oxygen delivery to the tissues is compromised.
Type B Lactic Acidosis occurs when either lactate production is increased or lactate removal is decreased without obvious oxygen delivery problems. It occurs due to increase in both endogenous and exogenous catecholamines. Enhanced β2 receptor activation leads to increased glycogenolysis, gluconeogenesis, lipolysis and ultimately to increased conversion of pyruvate to lactic acid. Concurrent corticosteroid use may enhance the beta receptor sensitivity further potentiating the lactic acidosis.
Conditions associated with type B lactic acidosis include inborn errors of metabolism (pyruvate dehydrogenase deficiency), systemic disorders (liver failure), and medications (ethanol, metformin, and corticoids). It has also been postulated that endogenous (distress) or exogenous (drugs) adrenergic stimulation may be associated with increased conversion of pyruvate to lactate.
What are the common blood gas findings in Acute Asthma?
The common metabolic disturbances seen during an acute attack are respiratory alkalosis, followed by respiratory acidosis as patients get tired of breathing.
What are the possible causes of lactic acidosis in Asthma?
1. Pulsus paradoxus and intrinsic PEEP decrease cardiac output and venous return
2. Production of lactate by overworked respiratory muscles
3. Hyperadrenergic State (Beta 2 agonist-induced)
Why is it important for us to know about this?
While treating asthmatic patients for severe bronchospasm, when lungs sound clear following treatment but tachypnea persists, suspect albuterol-induced hyperlactatemia.
- Dodda, Venkata R., and Peter Spiro. "Can albuterol be blamed for lactic acidosis?." Respiratory care 57.12 (2012): 2115-2118.
- Stratakos G, Kalomenidis J, Routsi C, Papiris S, Roussos C. Transient lactic acidosis as a side effect of inhaled salbutamol. Chest. 2002 Jul;122(1):385-6
- Stratakos G, Kalomenidis J, Routsi C, Papiris S, Roussos C: Transient lactic acidosis as a side effect of inhaled salbutamol. Chest 2002; 122: 385–6Stratakos, G Kalomenidis, J Routsi, C Papiris, S Roussos, C
- Prakash S, Mehta S: Lactic acidosis in asthma: Report of two cases and review of the literature. Can Respir J 2002; 9: 203–8Prakash, S Mehta, S