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L B Hilbrands

Publications and source records attributed to L B Hilbrands.

47 records · Page 3Linked to original sources
PubMed1993

[Wishes of residents in internal medicine with relation to working week, part-time work, career length and practice pattern].

To investigate the wishes and ideas about length of working week, part-time work, length of career and future kind of establishment, a questionnaire was sent to all Dutch registrars of internal medicine. In the opinion of more than 70 percent of the registrars, the length of a full-time working week of an internist should be less than 50 hours. Of all registrars (62% men and 38% women), 68% would decide in favour of part-time work if the length of a full-time working week of an internist were to remain at about 68 hours (common length of a working week of Dutch internists nowadays). 33% would still like to work part-time when the length of a full-time working week became as they desired (about 47 hours). The preferred length of their career was for most registrars less than 30 years. The majority preferred a tenure to a position in a partnership. In conclusion, the wishes about the future of the registrars of internal medicine differ markedly from the current situation.

Female↗
PubMed1993

Computer simulations in comparison with in vivo measurements of nifedipine-induced changes in renal allograft hemodynamics.

Analysis of Doppler spectrum waveforms is increasingly used in the differential diagnosis of human renal allograft dysfunction. The physiologic interpretation of changes in Doppler spectra obtained from renal allografts, however, remains a major problem. Computer simulation models of the renal circulation may provide insight into the physiologic mechanisms responsible for changes in Doppler spectrum characteristics. The results of measurements of renal allograft hemodynamics with both determinations of PAH clearance and Doppler spectrum analysis in 11 kidney allograft recipients were explained physiologically using a computer simulation model of kidney allograft hemodynamics. Using PAH clearance and blood pressure measurements a significant decrease in RVR was found (from 0.32 +/- 0.17 to 0.20 +/- 0.07 mm Hg x min/ml, P < 0.05) after administration of the vasodilatory drug nifedipine. The Doppler spectrum waveform obtained from interlobar renal arteries showed a decrease in the RI (from 0.60 +/- 0.04 to 0.56 +/- 0.06; P < 0.05) and Tmax (from 133 +/- 32 to 98 +/- 32 ms; P < 0.05). The user-designed simulation model of renal hemodynamics showed comparable changes of the waveform when, in the model, the analogs of blood pressure, impedance of the artery, and the impedance of the peripheral vascular bed were altered proportionally.

Administration, Oral↗
PubMed1992

Post-transplant haemoglobin levels and host kidney status.

Erythrocytosis after renal transplantation has been ascribed to inappropriate production of erythropoietin by the recipient's native kidneys. In a retrospective analysis we examined the effect of pre-transplant bilateral nephrectomy on post-transplant haemoglobin level (Hb) and haematocrit (Ht) in 370 renal transplant patients. Hb and Ht were significantly higher in the 341 patients with host kidneys in situ compared with the 29 patients who had undergone bilateral nephrectomy (Hb, 8.5 +/- 1.2 mmol/l vs 7.8 +/- 1.3 mmol/l, P = 0.005; Ht, 41 +/- 6% vs 38 +/- 7%, P = 0.02). Moreover, a very high Hb and/or Ht (defined as a value above the 80th percentile of the whole group) occurred more frequently in patients with host kidneys in situ (20.5% vs 3.5%, P = 0.02). It thus appears that host kidneys significantly contribute to the unexpectedly high haemoglobin levels occurring after renal transplantation.

Adult↗
PubMed1992

Haemodynamic changes in human kidney allografts following administration of nifedipine: assessment with Doppler spectrum analysis.

Cyclosporin (CyA) has been demonstrated to increase the vascular resistance of renal allografts (RVR), whereas calcium channel blocking agents like nifedipine may counteract this effect. In this study RVR was calculated from renal blood flow (RBF), measured by the clearance of para-aminohippurate (PAH), and mean arterial pressure (MAP). Analysis of Doppler spectra obtained under ultrasonographic guidance was used as a non-invasive method of assessing renal haemodynamics. A comparison was made between these two methods to detect changes in renal haemodynamics which were caused by the administration of 10 mg nifedipine orally to 11 renal transplant recipients treated with CyA. RBF increased significantly (444 +/- 176 vs 559 +/- 192 ml/min per 1.73 m2; P < 0.05) despite a decrease in MAP (116 +/- 10 vs 101 +/- 11 mmHg; P < 0.05) after administration of nifedipine. Calculated RVR decreased from 0.31 +/- 0.17 to 0.20 +/- 0.07 mmHg x min/ml (P < 0.05). Results of Doppler spectrum analysis were in concordance with these observations. Resistance index (RI) in interlobar arteries decreased from 0.60 +/- 0.04 to 0.56 +/- 0.06 (P < 0.05) and acceleration time (Tmax) of the Doppler spectrum decreased from 133 +/- 32 to 98 +/- 32 ms (P < 0.05). Theoretically, a lower RI and decreased Tmax indicate a reduced vascular resistance and changes in vascular wall compliance, respectively. Analysis of Doppler spectra may thus become a useful device for non-invasive assessment of acute changes in RVR.

Adult↗
PubMed1991

Cyclosporin A blood levels during use of cyclosporin as oral solution or in capsules: comparison of pharmacokinetic parameters.

Recently cyclosporin A (CsA) capsules have been introduced to meet a number of disadvantages associated with the use of the oral solution. We compared the pharmacokinetics of the oral solution and the capsules in a group of nine renal transplant patients during the first 3 weeks after transplantation. After a morning dose of CsA, whole blood concentrations were measured at regular intervals for 12 h. Subsequently, a cross-over was made to the alternative form of administration, and 3 or 4 days later a second pharmacokinetic profile was obtained. Comparison of the trough level, the maximum concentration, the time to reach the maximal concentration and the area under the blood concentration curve, showed no significant differences. Our findings thus suggest a similar bioavailability of CsA administered as oral solution or in capsules in the early post-transplant period.

Administration, Oral↗
PubMed1991

Cimetidine improves the reliability of creatinine as a marker of glomerular filtration.

To investigate whether the administration of cimetidine can improve the reliability of creatinine as a marker of GFR, we compared the creatinine clearance (CCr) to the clearance of the true filtration markers 51Cr-EDTA (CEDTA) and inulin (CIn), after oral ingestion of cimetidine in 10 healthy men and 29 patients with varying degrees of renal dysfunction. After administration of cimetidine for three to six days, serum creatinine level rose in all participants, while CEDTA and CIn remained stable in a subgroup of 14 subjects in whom they were measured before as well as after the administration of cimetidine. The mean (+/- SD) ratios of CCr to CEDTA (N = 39) and of CCr to CIn (N = 19) after ingestion of cimetidine were 1.02 +/- 0.13 and 1.01 +/- 0.13, respectively, and did not differ significantly from unity. This high degree of accuracy of the cimetidine-aided CCr was present over the entire range of renal function in the study population. Our results also indicated an improved precision of the cimetidine-aided measurement of CCr, resulting in a variability that did not differ significantly from that of the measurement of CEDTA or CIn. We conclude that after oral administration of cimetidine, the creatinine clearance can be used as a reliable measure of GFR within a broad range of renal function.

Adult↗