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Clinical and hemodynamic effects of stepwise lowering of hemoglobin concentration in patients with intermittent
F Celsing1, M Eriksson, U Markström
1Department of Medicine, Karolinska Institute, Danderyd Hospital, Stockholm.
Insights
Lowering hemoglobin (Hb) levels through venesection did not improve walking distance or hemodynamics in patients with intermittent claudication. This study found no clinical benefit from reducing Hb concentration in this patient group.
Area of Science:
- Vascular Medicine
- Hematology
Background:
- Intermittent claudication (IC) significantly impacts quality of life.
- Hemoglobin (Hb) concentration is a key factor in oxygen transport.
Purpose of the Study:
- To evaluate the effect of stepwise hemoglobin reduction on maximal walking distance (MWD) and hemodynamics in patients with severe intermittent claudication.
- To determine if hemodilution via venesection offers clinical benefits for IC patients.
Main Methods:
- A study group (n=6) underwent repeated venesections to lower Hb levels.
- A control group (n=6) did not undergo venesections.
- Measurements included MWD, transcutaneous oxygen pressure, heart rate, pain-free walking distance, ankle pressure, and blood lactate.
Main Results:
- Reducing Hb concentration from 151 +/- 4 to 121 +/- 3 g/L did not significantly alter MWD (282 +/- 62m vs. 255 +/- 54m).
- Transcutaneous oxygen pressure, maximal heart rate, pain-free walking distance, ankle pressure, and blood lactate remained unchanged.
- Venesection of ~1.4L whole blood over 14 days did not alter blood volume.
Conclusions:
- Hemodilution achieved through venesection does not provide clinically or physiologically beneficial effects for patients with severe intermittent claudication.
- Significant reductions in arterial oxygen content within the normal Hb range did not impact hemodynamics or clinical symptoms in IC patients.
Abstract:
This study evaluates the effect of stepwise lowering of the hemoglobin (Hb) concentration on maximal walking distance (MWD) and hemodynamics in patients with intermittent claudication. The results in a study group (n = 6) were compared with those of a control group (n = 6) whose members were not subjected to venesections. An average decrease of Hb concentration from 151 +/- 4 to 121 +/- 3 g/L did not significantly influence MWD, the result being 282 +/- 62 meters before venesections and 255 +/- 54 meters after three to five (mean four) repeated venesections. Transcutaneous oxygen pressure was measured at the dorsum of the foot before and after exercise and did not change with a gradual decrease of the Hb concentration. Maximal heart rate, painfree walking distance, ankle pressure, and blood lactate concentration were also unchanged. An average venesection volume of about 1.4 liters whole blood within fourteen days, without isovolemic replacement, did not change the blood volume, which was 5.1 +/- 0.4 liters before and 5.0 +/- 0.5 liters after venesections. In conclusion, hemodilution accomplished by venesections did not have a clinically or physiologically beneficial effect in patients with severe intermittent claudication. However, hemodynamics and clinical symptoms were not affected by a considerable decrease in the arterial oxygen content within the normal Hb concentration range.