A 36-year-old male with a history of chronic asthma presented to an emergency department with shortness of breath consistent with an asthma exacerbation. He had persistent tachypnea following inhaled bronchodilator treatment; thus, the workup and differential diagnosis were expanded. He was found to have a mixed respiratory alkalosis and metabolic acidosis with elevated serum lactate without an obvious cause and was admitted to hospital. His case was reviewed, and the lactic acidosis was thought to be caused by inhaled β2-agonist use. Emergency physicians should be aware of the potential side effects of inhaled β2-agonists as lactic acidosis may complicate clinical assessment and management of asthma exacerbations and lead to unnecessary and potentially dangerous escalations in therapy.

Summary

Background and objective: To investigate the effects of intra-aortic balloon pump therapy on parameters of global and regional oxygenation in patients undergoing cardiac surgery. Methods: As part of a large surveillance study in cardiac surgery patients (n = 266) we retrospectively analyzed the course of 28 patients requiring intra-aortic balloon pump therapy. Patients were grouped according to the time point of pump insertion (during weaning from cardiopulmonary bypass: group early intra-aortic balloon pumping (n = 17); after admission to the intensive care unit: group late intra-aortic balloon pumping (n = 9). Haemodynamic and tonometric variables, arterial lactate, and use of catecholamines were measured hourly. Measurements and results: Cardiac index increased in both groups after intra-aortic balloon pump insertion (2.2 ± 0.5 baseline; 3.4 ± 0.8 L min−1 m−2 4 h later (group early intra-aortic balloon pumping); 2.8 ± 0.5 baseline, 3.6 ± L min−1 m−2 4 h later (group later intra-aortic balloon pumping), each P < 0.05), there were no differences between groups. Arterial lactate values increased in group later intra-aortic balloon pumping after pump insertion to a maximum 2 h later (8.4 ± 6.1 mmol L−1 baseline; 12.7 ± 7.4 mmol L−1, P < 0.05), and decreased continuously afterwards. The difference of arterial and gastric CO2 showed a sharp decrease after pump insertion in group later intra-aortic balloon pumping (26.4 ± 9.8 baseline; 7.0 ± 11.1 mmHg, P < 0.05). There were no differences between groups. Epinephrine doses were higher in group later intra-aortic balloon pumping (P < 0.05). Conclusions: Intra-aortic balloon pump therapy improved global and regional splanchnic oxygenation in cardiac surgery patients with low-cardiac-output syndrome. Gastro-intestinal tonometry could provide additional information concerning tissue oxygenation. Patients with later intra-aortic balloon pump insertion needed more catecholamine therapy to achieve similar haemodynamic values.

Nucleoside analogue-induced lactic acidosis is an often fatal condition in patients with HIV. There is only one report of successful treatment with riboflavin. We describe a 30-year-old female with AIDS and nucleoside analogue-induced lactic acidosis that exacerbated shortly after introducing total parenteral nutrition and reversed within hours after the addition of thiamine. Successful treatment of nucleoside analogue-induced lactic acidosis with a high dose of thiamine supports the hypothesis that vitamin deficiency is an important cofactor in the development of this rare and unpredictable condition in patients with HIV. We suggest that high dose B-vitamins should be given to any patient presenting with lactic acidosis under nucleoside analogue treatment.