No abstract

We conducted a prospective study to determine the relationship between central (CVP) and peripheral (PVP) venous pressures in critically ill patients. CVP and PVP were measured on five different occasions in 20 critically ill patients in the intensive care unit. Results showed that the mean difference between PVP and CVP was 4.4 mmHg (95% CI= 3.7 to 5.0). However, PVP might be 1.9 mmHg below (95% CI=0.7 to 3.1) or 10.6 mmHg above (95% CI=9.4 to 11.8) the CVP. The mean difference between changes in PVP and corresponding changes in CVP was 0.3 mmHg (95%CI=-0.1 to 0.7). The actual change in PVP could be 3.0 mmHg below (95% CI=2.3 to 3.7) or 3.6 mmHg above (95% CI=2.9 to 4.3) the change in CVP. Overall, the direction of change in PVP (rise or drop) predicted a same direction of change in CVP with an accuracy of 78%. Changes in PVP ≥2 mmHg predicted a change in same direction of CVP with an accuracy of 90%. The direction of changes in CVP ≥2 mmHg were predicted by the direction of change in PVP with an accuracy of 91%. We conclude that PVP measurement does not give an accurate estimate of the absolute value of CVP in individual patients. However, as changes in PVP parallel, in direction, changes in CVP, serial measurements of PVP may have a value in determining volume status and guiding fluid therapy in critically ill patients.

No abstract

Primitive hematopoietic cells released into the peripheral blood (PB) were studied in 50 patients with high-grade non-Hodgkin's lymphoma enrolled in a phase III trial of intensive weekly chemotherapy (VAPEC- B) alone or with granulocyte colony-stimulating factor (G-CSF). Mononuclear cells numbers were monitored and their in vitro growth potential assessed in clonogenic progenitor cell assays and in long- term culture. Total colony-forming cells (granulocyte-macrophage [GM], burst-forming unit, erythroid [BFU-E], Mix-CFC) were increased 40-fold (median) over baseline with chemotherapy alone and 106-fold with chemotherapy and G-CSF after the final dose. CD34+ cells were increased to a median of 4%, equivalent to that in normal bone marrow (BM) controls. Circulating colony-forming cell levels were maximal when the recovering total white blood cell (WBC) count reached 5 to 10 x 10(9)/L. The timing of the maximum was reproducible in individual patients. Therefore the WBC count can be used as a guide to the timing of leukapheresis. PB cells from normal controls' and patients' prechemotherapy were unable to sustain hemopoiesis in two-stage long- term cultures. In contrast, PB cells collected from patients primed with chemotherapy alone or chemotherapy with G-CSF at the time of predicted maximal colony-forming cell release were able to generate and sustain hematopoiesis in long-term cultures at a level comparable or superior to normal BM. These findings indicate that the use of G-CSF after routine outpatient chemotherapy stimulates maximal release of primitive hemopoietic cells into the circulation, including colony- forming cells and long-term culture-initiating cells. Their numbers are comparable with those in normal BM and are such that a single leukapheresis will usually yield enough cells for hemopoietic reconstitution after myeloablative chemotherapy.