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T Schuerholz

Publications and source records attributed to T Schuerholz.

8 recordsLinked to original sources
PubMed2006

Haemodynamic, acid-base and blood volume changes during prolonged low pressure pneumoperitoneum in rabbits.

BACKGROUND: The anaesthetic management of small infants during advanced laparoscopic surgery can be complicated by the major pathophysiological effects of increased intra-abdominal pressure. In this study haemodynamic, acid-base and blood volume changes were investigated during pneumoperitoneum in a small animal model. METHODS: Ten fasted, anaesthetized, mechanically ventilated and multi-catheterized New Zealand rabbits were randomized to carbon dioxide pneumoperitoneum (PP, duration 210 min, pressure 8 mm Hg) or control group. Cardiac index was determined using trans-cardiopulmonary thermodilution and total blood volume was measured by thermal-dye dilution with indocyanine green using a fibreoptic monitor system. RESULTS: In PP cardiac index (CI), central venous oxygen saturation (Scv(O(2))), total blood volume (TBV) and base excess (BE) decreased significantly during the study whereas all variables remained constant in the control group. After release of PP the measured variables did not return to baseline within 30 min [PP, baseline vs study end: CI 108 (22) vs 85 (14) ml kg(-1) min(-1), Scv(O(2)) 81.4 (8.9) vs 56.7 (9.8)%, TBV 318 (69) vs 181 (54) ml, BE -1.9 (2.7) vs -8.7 (1.8) mmol litre(-1); P<0.01]. CONCLUSION: Our animal model suggests that a decrease in CI, metabolic acidosis and hypovolaemia could occur after prolonged low pressure pneumoperitoneum in small infants, which is possibly not detectable by the standard monitor setting. Therefore, the routine use of an extended monitoring including measurement of central venous oxygen saturation and acid-base parameters should be considered during and soon after operation, when pneumoperitoneum will last longer than 2 h.

Acidosis↗
PubMed2006

Reliability of continuous cardiac output determination by pulse-contour analysis in porcine septic shock.

BACKGROUND: Pulse-contour analysis represents a technique for cardiac output (CO)-measurement and allows continuously monitoring trends in CO. We evaluated reliability of pulse-contour CO (COpc) in septic shock. METHODS: Seventeen anaesthetized and mechanically ventilated pigs were investigated. After baseline measurements, 14 animals received 0.75 g/kg body weight faeces into the abdominal cavity to induce sepsis and were observed over 9 h, three animals served as controls. A central venous catheter was inserted into the jugular vein and an arterial catheter for thermodilution was inserted into the femoral artery. Two bedside computers were used for COpc. After induction of sepsis, COpc-computer No. 1 (COpcCAL) was recalibrated hourly. No further calibrations were performed in computer No. 2 (COpcNoCAL). We directly compared COpcCAL hourly before recalibration with COpcNoCAL. One hundred and seventy parallel triplicate determinations of CO were analysed using the method of Bland-Altman. RESULTS: Three hours after sepsis induction, correlation between recalibrated and non-recalibrated CO was r = 0.74, P < 0.01, at 5 h r = 0.59, P < 0.05 and 9 h r = 0.02, NS. Three hours after sepsis induction, bias +/- SD (limits of agreement) between both groups was 1.6 +/- 15.5 (-29.4-32.6) ml/kg/min, at 5 h -15.0 +/- 24.3 (-63.6-33.7) ml/kg/min and at 9 h -87.0 +/- 90.8 (-268.5-94.6) ml/kg/min. CONCLUSION: Continuous CO determination using pulse-contour analysis is a reliable method of assessing CO up to 5 h without recalibration in porcine septic shock. Thus, COpc may be a useful tool for assessment of unpredictable haemodynamic changes in sepsis.

Animals↗
PubMed2005

[New approaches to intensive care for sepsis].

In Germany, the mortality from sepsis remains high, and up to 60,000 patients die from it each year. Thus, sepsis is the third most common cause of death. More deaths occur only from coronary heart disease and acute myocardial infarction. In the last 3-4 years, substantial progress in sepsis therapy has been made. Based on these achievements, there is hope of reducing sepsis mortality by 25% in the next few years. Implementing new medical evidence in this context into daily clinical intensive care remains a major hurdle. The early diagnosis of sepsis prior to the onset of clinical deterioration is of particular interest, because this would increase the possibility of early and specified treatment, which is in turn the major determining factor of mortality in septic patients.

Cause of Death↗
PubMed2005

Comparison of cardiac output measurements by arterial trans-cardiopulmonary and pulmonary arterial thermodilution with direct Fick in septic shock.

BACKGROUND AND OBJECTIVE: The aim of this study was to compare cardiac output (CO) measurements by arterial trans-cardiopulmonary thermodilution (ATD) and pulmonary arterial thermodilution (PATD) with CO estimated on the basis of the Fick calculation via a metabolic monitor in septic shock. METHODS: In a prospective animal study 20 anaesthetized, ventilated pigs (20.9 +/- 1.9 kg) were investigated. Septic shock was induced with faecal peritonitis. A pulmonary artery catheter was used for conventional measurement of CO. Simultaneously ATD was measured with a thermistor tipped catheter inserted into right carotid artery. Whole body oxygen consumption was measured by indirect calorimetry. Eighty data pairs of simultaneous CO measurements were analysed. RESULTS: CO measured with Fick and that measured with PATD were significantly correlated (r = 0.94, r = 0.87, P < 0.001). Mean CO measured by PATD was 94.3 +/- 40.1 mL min(-1) kg(-1). Bias was 10.1 mL min(-1) kg(-1) (95% confidence interval (CI): 6.0-14.2 mL min(-1) kg(-1)) with limits of agreement of -26.8 to 47.0 mL min(-1) kg(-1). Correlation between Fick derived CO estimation and ATD CO was similar (r = 0.91, r2 = 0.83, P < 0.001). Mean CO measured by trans-cardiopulmonary thermodilution was 104.3 +/- 43.2 mL min(-1) kg(-1). Bias was 0.75 mL min(-1) kg(-1) (95% CI: -3.8 to 5.3 mL min(-1) kg(-1)) with limits of agreement of -39.7 to 41.2 mL min(-1) kg(-1). CONCLUSIONS: Even during haemodynamic instability in septic shock the correlation of arterial trans-cardiopulmonary thermodilution and PATD derived CO with direct Fick was good. As arterial trans-cardiopulmonary thermodilution is less invasive than PATD, the former may offer practical advantages.

Algorithms↗
PubMed2005

Terminal complement complex in septic shock with capillary leakage: marker of complement activation?

BACKGROUND AND OBJECTIVE: The aim of this study was to evaluate the value of terminal complement complex (C5b-9) plasma levels as a marker for complement activation in septic shock with concomitant capillary leak syndrome. METHODS: In a prospective animal study 10 fasted, anaesthetized, mechanically ventilated and multi-catheterized pigs (20.6 +/- 1.3 kg) were investigated over a period of 8 h. Sepsis was induced by faecal peritonitis (1 g kg(-1) body weight faeces, n = 5) and compared to controls (n = 5). The animals received 6% hydroxyethyl starch 200/0.5 to maintain a central venous pressure of 12 mmHg. To quantify capillary leak syndrome, albumin escape rate was measured using 99mTc-labelled human serum albumin. Plasma levels of terminal complement complex were measured in a double antibody immunoassay (neoepitope-specific MoAb aE 11 as catching antibody). Immunohistological studies of renal specimens were performed to detect terminal complement complex deposition. RESULTS: Albumen escape rate increased in septic animals (+ 52%) compared to controls (+ 3%, P < 0.05). Plasma levels of terminal complement complex decreased during the study period in both groups. In septic animals this finding was accompanied by a significant deposition of terminal complement complex in renal specimens (P < 0.05). CONCLUSION: We found an activation of the complement system proven by marked deposition of terminal complement complex in renal specimen, while its plasma levels decreased during the study period in septic and control animals. These results suggest that in septic shock with capillary leak syndrome plasma level of terminal complement complex may not be a reliable marker of complement activation.

Animals↗
PubMed2004

Ringer's solution but not hydroxyethyl starch or modified fluid gelatin enhances platelet microvesicle formation in a porcine model of septic shock.

BACKGROUND: Sepsis is associated with volume deficit and clotting system activation. Platelet activation in sepsis results in an increased formation of microvesicles, which in turn, have been associated with increased mortality. We hypothesized an effect of different volume replacement solutions on platelet-derived microvesicle formation in septic shock. METHODS: Anaesthetized, mechanically ventilated and multi-catheterized pigs received 1 g kg(-1) body weight faeces into the abdominal cavity to induce sepsis and were observed over 8 h. Five animals in each group received volume replacement therapy with modified fluid gelatin 4% or 8% (MFG4%, MFG8%), 6% hydroxyethylstarch (HES) 200/0.5 or Ringer's solution (RS) to maintain a central venous pressure of 12 mm Hg. Flow cytometry was used for determination of microvesicles before induction of sepsis (baseline) and after 8 h. Platelets and microvesicles were identified with an anti-platelet monoclonal Ab and a secondary antibody. Microvesicles were determined as the smallest 1-3% positive cells in forward scatter. Intergroup comparisons were performed using Wilks-Lambda and Ryan-Einot-Gabriel-Welsh F-test. Differences within groups were compared using a two-tailed Student's t-test. RESULTS: Baseline values were considered as 100%. While microvesicle formation was reduced in HES (73 (sd 19)%), MFG4% (63 (41)%) and MFG8% groups (53 (17)%), an increase in the RS-group (210 (121)%) was observed. Eight hours after induction of sepsis, formation of microvesicles was significantly higher in the RS group compared to all colloid-treated groups. CONCLUSION: In this porcine septic shock model the formation of platelet-derived microvesicles was significantly increased by volume replacement with Ringer's solution in comparison to colloid solutions.

Animals↗
PubMed2002

Hydroxyethyl starch and modified fluid gelatin maintain plasma volume in a porcine model of septic shock with capillary leakage.

OBJECTIVE: To compare the effects of different volume replacement therapies on maintenance of plasma volume in septic shock and capillary leakage syndrome. DESIGN AND SETTING: Prospective randomized, controlled animal laboratory study in a university animal laboratory. MEASUREMENTS AND RESULTS: Twenty-five fasted, anaesthetized, mechanically ventilated and multi-catheterized pigs (20.8+/-1.8 kg) received 1 g/kg body weight faeces into abdominal cavity to induce sepsis and were observed over 8 h. Five animals each received volume replacement therapy with modified fluid gelatin 4% or 8% (MFG4%, MFG8%), 6% HES 200/0.5, or Ringer's solution and were compared to controls receiving 6% HES 200/0.5. Infusion rate was titrated to maintain a central venous pressure of 12 mmHg. Plasma volume was determined using (51)Cr-labelled erythrocytes and standard formulae. Albumin escape rate was calculated using technetium (99m)Tc-labelled albumin. Colloid osmotic pressure, systemic haemodynamics and oxygenation were obtained before and 4 and 8 h after induction of sepsis. Plasma volume was reduced in the Ringer's solution group (-46%) but was maintained in HES (+/-0%), MFG4% (+4%), MFG8% (+23%) groups. Albumin escape rate increased in HES (+52%), MFG4% (+47%), MFG8% (+54%) and the Ringer's solution group (+41%) compared to controls. CONCLUSION: In this porcine septic shock model with concomitant capillary leakage syndrome, confirmed by an increased albumin escape rate, the artificial colloids HES, MFG4%, and MFG8% maintained plasma volume and colloid osmotic pressure. These results suggest the intravascular persistency of artificial colloids in the presence of albumin leakage. An editorial regarding this article can be found in the same issue (http://dx.doi.org/10.1007/s00134-002-1283-9)

Albumins↗