Lactate Levels as Predictors of the Relationship between Oxygen Delivery and Consumption in ARDS: Results

In: ARDS

17 Jan 2013

Lactate Levels as Predictors of the Relationship between Oxygen Delivery and Consumption in ARDS: ResultsDescriptive features of patients with normal aqd with elevated lactate levels are shown in Table 1. The alveolar-arterial oxygen tension gradient and mortality were significantly higher in the elevated lactate group. A higher proportion of patients in the increased lactate group exhibited a change in Vo2 in the same direction as the change in Do2, consistent with a supply-dependent pattern of oxygen utilization (Table 1). Changes in Vo2 in response to a change in Do2 for all interventions (fluids, blood, and PEEP) are shown in Figure 1 and Table 2. The group with lactic acidosis exhibited a significant change in Vo2 corresponding to changes in Do2. In spite of a significant change in Do2 for patients without lactic acidosis, a significant corresponding change in Vo2 was not observed. The Vo2 response in this group can be considered insignificant, with a statistical power of 0.8. ventolin inhalers
Patients who received PEEP as an intervention were analyzed separately, and the results are shown in Table 3. All patients exhibited a decrease in Do2 associated with a reduction in cardiac output observed after the implementation of PEEP Patients with lactic acidosis exhibited significant decreases in Vo2 associated with the decrease in Do2. A significant decrease in Vo2 was not observed in patients without lactic acidosis, although this negative result could not be assured with a statistical power of more than 0.8.

Table 1—Descriptive Information

Lactate Level
Data Normal Increased
No. of patients 26 32
Lactate level, mmol/L 2.0 ±0. I 4.9±0.5
Cl, L/min/m2 3.7±0.4 3.8 ±0.2
Hb level, g/dl 10.9 ±0.5 9.8 ±0.4
Venous admixture, percent 31.4 ±2.8 36.5 ±2.1
Alveolar-arterial oxygen tension
difference, mm Hg 289 ± 29 377 ±22
Arterial/alveolar oxygen tension
ratio, percent 31±3 22±2
Mortality, percent 65 94
No. exhibiting direct
relationship between Vo8 and
Do2 (percent) 14 (54)|| 26 (81)||
Interval between initial and
final Do2 and Vo2
measurements, h 4.4±0.4 3.9±0.3

Table 2—Effects of All Interventions (Fluids, Blood, and Application of PEEP) on Dot and Vo

Normal Lactate (n = 26) Increased Lactate (n = 32)
Data Lowest Highest Lowest Highest
Do2) ml/min/m2 Vo2, ml/min/m2 488 ±41 142 ±11 601 ±51 151 ±11 454 ±27 118 ± 7 591 ±37 152±lit

Table 3—Effects of PEEP on Do% and Vo

Normal Lactate (n = 6) Increased Lactate (n = 10)
Data Before PEEP After PEEP Before PEEP After PEEP
Do2, ml/min/m2 Vo2, ml/min/m2 754 ±169 161 ±42 650 ±138 180 ±42 635 ±63 139 ±16 531± 52t 116 ±12

Figure-1

Figure 1. Change in Vo* in response to change in Do, for all patients, as outlined in Table 1. Squares represent patients with elevated blood lactate levels; circles denote patients with lactate concentrations of 2.4 mmol/L or less.


About this blog

Blog invites submissions of review articles, reports on clinical techniques, case reports, conference summaries, and articles of opinion pertinent to the control of pain and anxiety in dentistry.

Photostream

Future-Farmers-Of-America
Massive NIH Grant to Study Benefits of SMT for Back Pain https://t.co/aTw5IPC02k
Federal agencies partner for military and veteran pain management research https://t.co/3DnUOgQ1Lt https://t.co/zrodBLjyKd
Artemisia - mugwort, wormwood, and sagebrush belonging to the daisy family Asteraceae
Artemisia - mugwort, wormwood, and sagebrush belonging to the daisy family Asteraceae
Bunch of juniper berries on a green branch in autumn
Bunch of juniper berries on a green branch in autumn
Bunch of juniper berries on a green branch in autumn
Stethoscope and keyboard macro concept

Tags