Search PubMed⌕ Search

Biomedical subjects

H Forst

Publications and source records attributed to H Forst.

At least 55 records · Page 3Linked to original sources
PubMed1993

[Dependence of O2 uptake on O2 transport--a myth or reality?].

According to the concept of supply dependence of oxygen uptake, an improvement of tissue oxygenation in critically ill patients may be obtained by an increase in systemic oxygen transport. A critical review of available clinical data suggests that a positive correlation between calculated oxygen uptake and oxygen delivery does not necessarily imply a 'pathological' dependence of both parameters. Possible pitfalls in the interpretation of results, like mathematical coupling of data, alterations in oxygen demand due to variations in sedation and the calorigenic effect of catecholamines, are discussed.

Catecholamines↗
PubMed1992

[Subcapsular hematoma of the liver in HELLP syndrome. An interdisciplinary emergency].

The HELLP-syndrome (Hemolysis, Elevated Liver enzymes, Low Platelets), known as a complication during pregnancy, is associated with preeclampsia and may cause subcapsular liver hematomas. In case of hepatic rupture the lives of mother and unborn are threatened. Therefore, an interdisciplinary diagnostic and therapeutic approach is discussed and compared to two examples. The diagnosis of subcapsular liver hematoma must lead to urgent delivery through Cesarean section. Thereafter, the surgeon may decide between observation on an intensive care unit and urgent operation in case of hepatic rupture, without endangering the unborn.

Adult↗
PubMed1992

Systemic antibiotic treatment of nosocomial pneumonia.

Nosocomial pneumonia continues to represent a significant cause of morbidity and mortality in hospitalized patients. Bacteria are responsible for greater than 90% of the pneumonias, the most common isolates being aerobic Gram-negative bacilli and S. aureus. Cornerstones of treatment are intravenous antibiotics and supportive care. In the individual case the true etiology is usually unknown; therefore empiric broad spectrum treatment is commonly used based on the prevalence of local pathogens, their antibiotic sensitivity pattern and on host factors. Combination antibiotic regimens, including beta-lactams and aminoglycosides, are considered as standard therapy and are associated with clinical success rates of greater than 80%. Monotherapy with broad spectrum antibiotics, such as third generation cephalosporins, imipenem and fluoroquinolones, can be considered as equally effective in non-neutropenic patients and in the absence of P. aeruginosa infection. More active and less toxic antibiotics are still needed for problematic pathogens such as methicillin-resistant S. aureus strains, multiresistant Enterobacteriaceae and Pseudomonas species. Because further improvement in morbidity and mortality may be limited with antibiotics alone, new emphasis should be placed on prevention of infection and the use of immunotherapy.

Anti-Bacterial Agents↗
PubMed1992

[Acute cholecystitis: percutaneous transhepatic drainage].

Despite emerging endoscopic techniques for treatment of gallbladder diseases the operative cholecystectomy is the treatment of choice in acute cholecystitis. Percutaneous cholecystostomy is an alternative treatment modality in poor surgical risk patients. In 19 out of 36 patients with percutaneous cholecystostomy no subsequent cholecystectomy was performed. A long-term observation of these 19 patients showed normal function of the gallbladder in ultrasound studies, thus percutaneous drainage can be a definitive treatment for acute cholecystitis in selected cases.

Aged↗
PubMed1992

[The determination of plasma volume using indocyanine green in man].

The importance of circulating blood (BV) and plasma volume (PV) in critically ill patients and physiological research is unchallenged. Recently, Evans blue (EB) [8, 25] and radioactively labelled serum albumin (RIHSA) [20] have mostly been used as tracers for PV determination. However, the disadvantages of radioactive contamination (RIHSA) and dye accumulation (EB), especially in repeated measurements, are obvious. In addition, recent reports show a possible carcinogenic potential for EB [15, 21]. This has prompted us to examine the feasibility of indocyanine green (ICG), a tricarbocyanine dye currently used for cardiac output and liver blood flow measurements, for the determination of PV. The volume of distribution of ICG has been reported to represent PV [5, 26]. METHODS. In 23 healthy volunteers (19 men and 4 women), PV was determined in duplicate (PV1, PV2) with an interval of 30 min. Before injection a tourniquet was put around the arm and a pressure above the systolic arterial pressure was applied for 2 min. During recirculation, ICG (2.5 mg/ml) was administered in a dose of 0.25 mg/kg as a bolus injection over 5 s via an antecubital vein. Blood was drawn from an antecubital vein of the contralateral arm at 1 min intervals. After centrifugation, the optical density (corrected for blank) was read in a densitometer. Third- to ninth-minute plasma samples were used to calculate monoexponential plasma decay curves. The ICG concentration at injection time was achieved by extrapolation. A calibration curve was generated using 5 different known ICG concentrations. PV was calculated from injected ICG dose divided by ICG concentration at injection time. BV and red cell volumes (EV) were derived from measured PV and hematocrit (hct). RESULTS. Between minutes 3 and 9, tracer decay was monoexponential in all but 1 subject. From minute 10 on the plasma decay of ICG represented another, slower compartment (Fig. 1). The plasma half-life of ICG was 3.2 +/- 0.6 min (mean +/- SD). Mean PVs per body weight and body surface area (BSA) were 44 +/- 5 ml/kg and 1662 +/- 176 ml/m2, respectively. Linear regression revealed PV2 = 0.92.PV1 + 226 (r = 0.92) (Fig. 2). The mean percentage of difference (D) was -0.6%, the methodologic error (SD) +/- 5.7% [27]. Linear regression of PV and BSA revealed PV = 1885.BSA -416 (r = 0.71, P less than 0.0001) (Fig. 3). BV and EV estimates (Table 2) obtained from PV and hct showed reproducibility in the range of the PV determination because of excellent reproducibility of hct measurements. DISCUSSION. ICG plasma half-life times in our experiments were comparable to those reported by other authors [18, 19, 24]. Reproducibility of PV determination was good and was well within the limits of other tracer methods (EB, RIHSA) [17, 27]. Using exclusively peripheral veins for ICG injection and blood withdrawal did not seem to affect the accuracy of PV determination. PV estimates obtained by the ICG method showed good agreement with those known from the literature [7, 10, 25]. Our results correspond especially well with the data reported by Hurley [14] obtained from 481 healthy men using different methods (Evans blue, RIHSA, or labelled red cells).

Adult↗