PT  - JOURNAL ARTICLE
AU  - Ambika Talwar
AU  - Vikas Punamiya
AU  - Shiva Bikmalla
AU  - Sushil Agarwal
AU  - Ben Beauchamp
AU  - Rahul Mukherjee
TI  - Acidotic hypercapnia: Beyond type 1 and type 2 respiratory failure
DP  - 2012 Sep 01
TA  - European Respiratory Journal
PG  - P2036
VI  - 40
IP  - Suppl 56
4099  - http://erj.ersjournals.com/content/40/Suppl_56/P2036.short
4100  - http://erj.ersjournals.com/content/40/Suppl_56/P2036.full
SO  - Eur Respir J2012 Sep 01; 40
AB  - Introduction: The indications of non-invasive ventilation (NIV) have widened in the recent years, which is now used in treating hypercapnia with acidosis in a variety of patients. However, in many of the patients treated with NIV, the acidosis may have preceded the hypercapnia. The current case series from our 11-bedded ward based NIV unit describes such acidotic hypercapnia: hypercapnic respiratory failure following metabolic acidosis.Methods: Time series of Arterial Blood Gas (ABG) findings in 4 patients with acidotic hypercapnia with a background of COPD confirmed with spirometry.Results:The ABGs for cases 1 and 2 showed a rising CO2 following the onset of a metabolic acidosis; a mixed metabolic and respiratory acidosis in patients 3 & 4 - with the acidosis preceding hypercapnia (Case 3) or being out of proportion to CO2 rise (Case 4). All four patients improved with initiation of NIV combined with active fluid/electrolyte management. A sample ABG time series (Case 3) showing initial eucapnia with acidosis leading to hypercapnia is shown:View this table:Acidosis preceding hypercapnia on ABG Time seriesDiscussion: Acidotic hypercapnia could be a further subtype of respiratory failure (akin to previously described Type 4 or shock-muscle hypoperfusion related respiratory failure) for which larger confirmatory studies and prospective trials to establish the efficacy and timing of NIV are required.