Metabolic acidosis is often the major finding in patients with septic shock (SS), with pH as low as 6.90. There are few published data to date comparing patient outcomes among those intubated and non-intubated for metabolic acidosis secondary to SS. There are currently no generally accepted guidelines for initiating mechanical ventilation in such cases. This study examines patient profiles, including pH on admission, as well as mortality in non-intubated patients (NIP) with SS.
A cross-sectional survey of patients admitted with SS over the period of Jul. 2004 to Jun. 2007 to an MICU was conducted. NIP ≥ 18 years, lactate > 2 mmol/L, AG > 12, SBP < 90, WBC of < 4K or > 10K were included. Exclusion criteria were any other disorders that might interrupt adequate ventilation or acid-base status such as COPD, pulmonary edema, DKA, CRF, MI and stroke on admission. We examined the incidence of mortality during admission and course of hospital stay.
During the study period 149 subjects were found to be eligible for evaluation. The pH on admission ranged from 6.93 to 7.39 (median 7.28, IQR: 7.24 to 7.35). 49 subjects (33%) died. All deaths were related to cardiopulmonary arrest secondary to sepsis and metabolic acidosis.
Subjects admitted with SS, especially those who have a pH of < 7.20 or have respiratory acidosis along with metabolic acidosis, may require intubation electively, as they appear not to be able to mount adequate compensatory response through hyperventilation .
Low pH (< 7.20) is a good guide in determining the need for initiating mechanical ventilation in patients with severe metabolic acidosis secondary to SS.
Fawad Chaudry, No Financial Disclosure Information; No Product/Research Disclosure Information