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M Heesen

Publications and source records attributed to M Heesen.

43 records · Page 3Linked to original sources
PubMed1995

Does the type of volume therapy influence endothelial-related coagulation in the critically ill?

The endothelium plays an important role in the regulation of haemostasis by producing substances such as thrombomodulin (TM). The influence of long-term volume replacement with different types of fluid on the TM-protein C-protein S system was investigated in a prospective, randomized study. Thirty trauma patients and 30 patients suffering from sepsis after major surgery received either 10% low-molecular weight (LMW) hydroxyethylstarch solution (HES-trauma, n = 15; HES-sepsis, n = 15) or 20% human albumin (HA-trauma, n = 15; HA-sepsis, n = 15) for 5 days to maintain central venous pressure (CVP) between 12 and 16 mm Hg. Plasma concentrations of TM, protein C, (free) protein S and thrombin-antithrombin (TAT) were measured in arterial blood samples obtained on the day of admission to the intensive care unit or on the day of diagnosis of sepsis and over the next 5 days. There were no differences between HA- and HES-treated trauma patients. Protein C and protein S also did not differ between HA- and HES-treatments. At baseline, TM plasma concentrations were increased to > 40 micrograms litre-1 in both sepsis groups only. In the HA-sepsis group, TM increased significantly (from 48.1 (SD 13.9) to 68.4 (13.0) micrograms litre-1), whereas it remained almost unchanged in the HES-sepsis group. In HES-sepsis patients, protein C (from 51.0 (10.1) to 71.9 (8.9)%) and protein S (from 19.0 (6.0) to 40.8 (11.4)%) increased significantly during the study, whereas both remained reduced in HA-patients. TAT (indicating intravascular coagulation) did not differ between the two fluid groups. We conclude that in trauma patients, the type of volume therapy had no influence on the TM-protein C-protein S system. In sepsis patients, volume therapy with HES was beneficial, whereas infusion of HA had no substantial positive effect on endothelial-associated coagulation.

Adult↗
PubMed1995

Beta 2-adrenoceptor density of human lymphocytes after nitroprusside-induced hypotension.

The present study was undertaken to assess the influence of nitroprusside-induced hypotension on beta 2-adrenoceptor density. Twenty-four patients undergoing nose-septum corrections under general anesthesia were allocated randomly to a nitroprusside or control group. beta 2-Receptor density on lymphocytes was measured by binding studies using (-)125-iodocyanopindolol. Lymphocyte subpopulations B, T, Thelper, Tsuppressor, and natural killer cells were determined simultaneously by flow cytometry. Five of 12 nitroprusside-treated patients developed significant intraoperative increases of epinephrine levels (+69% versus preoperatively) which were not seen in the remaining seven patients. In these five patients, beta 2-receptor density of unfractionated lymphocytes was 26% lower (P < 0.05) on the first day after surgery compared with preoperative values. Since no changes in proportions of lymphocyte subpopulations were observed, these results are not caused by redistribution phenomena inducing a decrease of subsets with a high number of beta receptors. These findings suggest that beta 2-adrenergic responsiveness might be diminished after nitroprusside treatment in some patients.

Adrenergic beta-Antagonists↗
PubMed1995

Cardiorespiratory effects of continuous i.v. administration of the ACE inhibitor enalaprilat in the critically ill.

1. Cardiorespiratory effects of long-term, continuous i.v. administration of the ACE inhibitor enalaprilat were studied. 2. Forty-five consecutive critically patients suffering from trauma or postoperative complications were randomly separated into three groups (15 patients in each group) receiving either 0.25 mg h-1 or 0.50 mg h-1 enalaprilat, respectively, or saline solution as placebo (= control group). The infusion was continued for 5 days. 3. Haemodynamic and respiratory parameters were intensively monitored on admission to the intensive care unit (= 'baseline' values) and daily during the next 5 days. 4. Mean arterial blood pressure (MAP) decreased significantly only in the enalaprilat-treated patients, whereas heart rate (HR) remained unchanged in these patients. 5. Pulmonary capillary wedge pressure (PCWP) and pulmonary artery pressure (PAP) were decreased by enalaprilat (0.50 mg h-1: PAP (mean +/- s.d.) decreased from 28.0 +/- 4.1 to 24.0 +/- 3.0 mm Hg) and remained significantly lower than in the control group. In the untreated control group, cardiac index (CI), oxygen consumption (VO2I) and oxygen delivery (DO2I) significantly decreased, which was blunted by enalaprilat infusion. Oxygen extraction (O2-extr) increased in both enalaprilat groups (0.25 mg h-1: from 26.1 +/- 5.5 to 30.4 +/- 4.0%; 0.50 mg h-1: 25.2 +/- 5.6 to 30.9 +/- 4.4%) and decreased in the control patients. 6. Right ventricular haemodynamics improved by enalaprilat infusion (0.50 mg h-1: RVEF increased from 40.0 +/- 3.5 to 45.5 +/- 4.0%). Lactate plasma concentrations decreased in the group with 0.50 mg h-1 enalaprilat (from 1.9 +/- 1.0 to 1.3 +/- 0.3 mg dl-1) and increased in the control patients. 7. Continuous infusion of the ACE inhibitor enalaprilat exerted beneficial cardiorespiratory effects in the critically ill. The widespread common risk of altered perfusion with decreased CI, DO2, VO2, O2-extr and increased lactate concentration was blunted by enalaprilat infusion. 8. Although 0.5 mg h-1 enalaprilat was most effective, a dose of 0.25 mg h-1 also showed beneficial haemodynamic effects in the critically ill.

Adult↗
PubMed1995

Increase of interleukin-6 plasma concentrations and HLA-DR positive T-lymphocytes after hypotensive anaesthesia with sodium nitroprusside.

Interleukin-6 (IL-6), a cytokine involved in the pathogenesis of sepsis and septic shock, and lymphocyte subpopulations were measured in blood circulation of patients receiving sodium nitroprusside (SNP) for induction of hypotension. The aim of this study was to evaluate whether this procedure influences distribution of lymphocyte subsets and IL-6 response. 30 patients of ASA physical status I and II scheduled for nose-septum correction were randomly assigned to the SNP- or control group (without SNP). Patients were anaesthetized with fentanyl, etomidate and isoflurane in 66% nitrous oxide. SNP was administered continuously during 60 min and mean arterial blood pressure was reduced to 50 mmHg. Before and after induction of anaesthesia, 60 min after the beginning of the operation (end of SNP-infusion) and on the first postoperative day, IL-6 plasma concentrations were determined by ELISA. The percentages of B-, T-lymphocytes, T-helper, T-suppressor cells and HLA-DR positive (activated) T-lymphocytes were examined by direct immunofluorescence using monoclonal antibodies. On the first day after surgery IL-6 plasma concentrations were significantly elevated in the SNP-group compared to preoperative values. In this group the values were higher than in control patients [30.5 (10.9-47.5) pg/ml vs. 17.4 (8.5-21.5) pg/ml]. The percentage of HLA-DR positive T-cells was 25.8 +/- 4.9% in the patients with SNP on the first postoperative day; it was significantly higher than in control patients [16.5 +/- 3.7%]. We conclude that SNP-administration increases percentage of activated T-cells and IL-6 secretion.

Adolescent↗
PubMed1995

[Effect of controlled hypotension using sodium nitroprusside on platelet aggregation].

OBJECTIVE: To determine the influence of sodium nitroprusside (SNP) on platelet aggregation when this agent is used to induce hypotension during surgery. PATIENTS AND METHODS: Spontaneous platelet aggregation (SPA) determined by impedance measurement and induced platelet aggregation (IPA) determined by turbidimetry were studied in 30 subjects scheduled for elective ear, nose or throat surgery. Fifteen patients in the SNP group (SNPG) received SNP in doses adjusted to maintain a mean arterial pressure of 50 mmHg. Another 15 patients who did not receive SNP served as controls. RESULTS: SPA increased progressively in both groups. The greatest increase occurred after anesthetic induction (control group +172%, SNPG +48%); the highest level recorded was reached on the morning of the first day after surgery (control group +215%, SNPG +46%). IPA decreased after anesthetic induction (control group -21%, SNPG -40%) and stayed down throughout surgery. IPA was higher on the first morning after surgery than before the operation (control group +35%, SNPG +2%). SPA was significantly higher 60 minutes after start of surgery than before surgery in the control group; IPA and SPA were likewise higher in these patients the morning after surgery. CONCLUSIONS: Platelet aggregation increases during surgery and in the immediate postoperative period. This increase is attenuated when SPA is given to induce hypotension. SPA should be determined by measurement of impedance in whole blood when the nature of platelet aggregation during surgery is being studied, given that early increases in IPA can be masked as a result of the low sensitivity of turbidimetry.

Blood Coagulation Disorders↗
PubMed1994

[Lymphocyte subpopulations in controlled hypotension with sodium nitroprusside].

AIM: Induced hypotension is an anaesthesiological method to reduce blood loss in surgical patients. The aim of this study was to investigate whether induced hypotension with sodium nitroprusside (SNP) causes changes in lymphocyte subpopulations. METHODS: In a prospective randomised evaluation 30 patients undergoing elective oto-rhino-laryngological interventions were studied. In 15 patients SNP was administered to reduce the mean arterial pressure to 50 mmHg. There was a control group of another 15 patients. Anaesthesia was induced with etomidate and maintained with isoflurane. At 7 a.m. on the day of operation (T1), 10 minutes after induction of anaesthesia (T2), 60 minutes after T2 (T3, end of SNP-infusion), 120 minutes (T4) after T2; 180 minutes (T5) after T2, and at 7 a.m. on the following morning (T6) blood samples were taken. A new method (whole blood) was used to mark 6 different lymphocyte subpopulations with monoclonal antibodies which were measured by flow cytometry. RESULTS: In both groups a significant decrease in total lymphocyte count (from 32.7 x 10(9) cells/l preoperatively to 13 x 10(9) cells/l the following morning in the SNP-group and from 31 x 10(9) cells/l to 14.2 x 10(9) cells/l the following morning in the control group) was observed. In the SNP-group the HLA-DR positive T-lymphocytes increased from 11.8% at T1 to 19.2% at T5 and 22.3% at T6. No statistically significant changes were found in percentage of T-, T4-, T8-, B-lymphocytes and natural killer cells. CONCLUSION: The increase in the percentage of activated T-lymphocytes is possibly due to an activation of the sympatho-adrenergic system after sodium nitroprusside-infusion and a subsequent redistribution of these cells from other organs (bone marrow, spleen, lymph nodes). The cell-mediated and the humoral immunity are not altered by induced hypotension. In discussing this result, the age of the patients, the extent of the surgical trauma, the anaesthesiological procedure and the methodological aspects in the lymphocyte assay should be taken into consideration.

Adolescent↗