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D Bruegger

Publications and source records attributed to D Bruegger.

5 recordsLinked to original sources
PubMed2005

[Microcirculatory monitoring of sepsis].

Microcirculatory dysfunctions play a central role in the pathophysiology of sepsis and shock. Modern methods enable microvascular monitoring in man and offer the possibility to test the effect of novel therapeutical strategies for sepsis. Furthermore, these techniques may be future tools for the monitoring of critically ill patients. In this review, we will describe four microvascular monitoring devices and give an overview of the microcirculatory changes observed during the course of sepsis. Laser Doppler fluxmetry is an easy to use noninvasive technique to measure tissue perfusion enabling monitoring of the effect of different catecholamines on the gastric perfusion during sepsis. Increased microvascular permeability and altered blood flow in septic patients can be quantified by venous congestion plethysmography. Alterations in sublingual microvascular blood flow are detected by intravital microscopy in septic patients and were identified as an outcome predictor. Furthermore, the role of gastrointestinal pCO2-tonometry for microcirculatory monitoring of the perfusion of splanchnic organs during sepsis is discussed. The true clinical value of these techniques has yet to be established and will depend on larger clinical trials showing an impact on diagnostics and patient management.

Humans↗
PubMed2002

Influence of different cuff inflation protocols on capillary filtration capacity in human calves -- a congestion plethysmography study.

It has been suggested that venous congestion plethysmography (VCP) substantially underestimates microvascular permeability by activation of a veni-arteriolar constrictor mechanism, even when using small (< 25 mmHg) congestion pressure steps. We studied human lower limbs of 18 young healthy volunteers to test whether the congestion pressure step size of the VCP protocol has an influence on the values of the capillary filtration capacity (CFC) and isovolumetric venous pressure (P(vi)). Two different dual stage VCP pressure step protocols, with 3 and 10 mmHg steps, were used in randomised order and separated by a transient reduction in congestion pressure. Since lymph flow is known to increase after venous congestion, we also looked to see if changes in the estimated lymph flow (J(v)L) occur as a result of these VCP protocols. The measured CFC (median [25th; 75th percentile]) was 2.6 [2.5; 3.2] x 10(-3) ml (100 ml)(-1) min(-1) mmHg(-1) with the 3 mmHg pressure step protocol, which was not different from the value of 2.9 [2.7; 3.4] x 10(-3) ml (100 ml)(-1) min(-1) mmHg(-1) obtained with 10 mmHg pressure steps. However, when either of these step sizes was applied after a transient venous decongestion, significantly higher values of CFC, 4.0 [3.4; 4.1] x 10(-3) and 3.5 [3.1; 4.5] x 10(-3) ml (100 ml)(-1) min(-1) mmHg(-1), respectively, were obtained (P < 0.05). The assessment of P(vi) was also independent of the pressure protocol (10 mmHg: 8.0 [5.7; 13.2] mmHg and 3 mmHg: 15.7 [12.5; 18.5] mmHg), but when P(vi) was measured after the transient deflation, significantly higher values were found with both 10 and 3 mmHg steps (24.1 [20.9; 27.3] and 30.4 [28.9; 30.9] mmHg, respectively; P < 0.01). The transient pressure reduction was associated with a rise in estimated J(v)L from 0.04 [0.03; 0.05] to 0.12 [0.08; 0.18] and 0.04 [0.04; 0.05] to 0.09 [0.07; 0.10] ml (100 ml)(-1) min(-1), respectively (P < 0.01). The first stage data from these protocols shows that the value of CFC is not influenced by the size of the cumulative venous pressure steps, providing they are of 10 mmHg or less. The data also show that J(v)L can be estimated with small step VCP protocols. We hypothesise that the sudden reduction in cuff pressure after venous congestion is associated with a temporary upregulation of lymph flow. As the congestion pressure is raised again, there is a modulation of the enhanced lymph flow, such that the resulting CFC slope appears greater than that obtained in the first stage of the protocol.

Adult↗
PubMed2002

Microvascular changes during anesthesia: sevoflurane compared with propofol.

BACKGROUND: We have developed a non-invasive computer-assisted venous congestion plethysmograph to measure the microvascular parameters in the lower limbs. This enables the assessment of microvascular changes following the induction of standardized anesthesia with either sevoflurane or propofol. METHODS: In a prospective randomized trial we measured the capillary filtration coefficient (CFC), isovolumetric venous pressure (Pvi), an index of the balance of Starling forces, and limb blood flow 24 h preoperatively, immediately after induction of anesthesia and on the 1st and 2nd postoperative day. Anesthesia was maintained with either 1.0% sevoflurane and 5 microg/kg/h remifentanil or propofol (3 mg/kg/h), and 5 microg/kg/h remifentanil in 20 female patients undergoing breast surgery. RESULTS: Preoperatively we found no significant differences between the mean CFC values of the sevoflurane group (3.7+/-0.3 ml/min 100 ml tissue/mmHg x 10-3=CFCU) and the propofol group (3.5+/-0.3 CFCU). In the sevoflurane group CFC decreased significantly to 2.9+/-0.2 CFCU, whereas it was unchanged in the propofol group. Both groups revealed a significant reduction in Pvi during steady-state anesthesia. Limb blood flow remained unchanged. There was an overall significant positive correlation between the perioperative fluid substitution and the difference between the preoperative and intraoperative CFC values (r = 0.64, P<0.01). CONCLUSION: The decreased CFC in response to sevoflurane may result in less extravasation of fluids into the interstitial space, thereby reducing intraoperative fluid requirements. These data suggest that sevoflurane may be the preferred anesthetic agent in subjects susceptible to large intraoperative fluid shifts.

Adult↗
PubMed1999

Characterization of human papillomavirus in airway papillomas by histologic and biochemical analysis.

The role of human papillomavirus (HPV) in airway papillomas has been well defined in recent literature. The chronicity and recurrence of papillomas has been postulated to be a result of residual viral genome in tissue treated with standard laser techniques. Thirteen patients with airway papillomas were selected for study with polymerase chain reaction (PCR) methods to detect viral DNA. Specimens taken prior to laser therapy and specimens taken at laser margins were consistently positive for HPV DNA by PCR. The HPV DNA is apparently present in tissues after macroscopic disease has been ablated by laser techniques. Histologic analysis of laser biopsies demonstrated fragments of squamous epithelium with cytologic features of HPV infection. Laser treatment is ineffective in eradicating HPV-infected tissues from airway papillomas, and this finding supports the notion that recurrence is a product of HPV incorporated into tissue not ablated by laser irradiation. Specific methods, results, and clinical correlation will be discussed.

Adult↗