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Biomedical subjects

M Frass

Publications and source records attributed to M Frass.

At least 37 records · Page 2Linked to original sources
PubMed2000

Outcome and prognostic factors in critically ill cancer patients admitted to the intensive care unit.

OBJECTIVE: To assess survival in cancer patients admitted to an intensive care unit (ICU) with respect to the nature of malignancy, cause of ICU admittance, and course during ICU stay as well as to evaluate the prognostic value of the Acute Physiology and Chronic Health Evaluation (APACHE) III score. DESIGN: Retrospective cohort study. SETTING: ICU at a university cancer referral center. PATIENTS: A total of 414 cancer patients admitted to the ICU during a period of 66 months. INTERVENTIONS: None. MEASUREMENTS: Charts of the patients were analyzed with respect to underlying disease, cause of admission, APACHE III score, need and duration of mechanical ventilation, neutropenia and development of septic shock, as well as ICU survival and survival after discharge. Mortality data were compared with two control groups: 1362 patients admitted to our ICU suffering from diseases other than cancer and 2,776 cancer patients not admitted to the ICU. MAIN RESULTS: ICU survival was 53%, and 1-yr survival was 23%. The 1-yr mortality rate was significantly lower in both control groups. Patients admitted after bone marrow transplantation had the highest mortality. In a multivariate analysis, prognosis was negatively influenced by respiratory insufficiency, the need of mechanical ventilation, and development of septic shock during the ICU stay. Admission after cardiopulmonary resuscitation yielded high ICU mortality but a relatively good long-term prognosis. Admission after surgery and as a result of acute hemorrhage was associated with a good prognosis. Age, neutropenia, and underlying disease did not influence outcome significantly. Admission APACHE III scores were significantly higher in nonsurvivors but failed to predict individual outcome satisfactorily. All patients with APACHE III scores of >80 died at the ICU. CONCLUSION: A combination of factors must be taken into account to estimate a critically ill cancer patient's prognosis in the ICU. The APACHE III scoring system alone should not be used to make decisions about therapy prolongation. Admission to the ICU worsens the prognosis of a cancer patient substantially; however, as ICU mortality is 47%, comparable with severely ill noncancer patients, general reluctance to admit cancer patients to an ICU does not seem to be justified.

APACHE↗
PubMed2000

Epinephrine application via an endotracheal airway and via the Combitube in esophageal position.

OBJECTIVE: To compare plasma concentrations and cardiovascular effects of epinephrine after application via a conventional endotracheal airway and via the esophageal lumen of a new emergency airway, the esophageal tracheal Combitube. DESIGN: Prospective, randomized study. SETTING: Center for Biomedical Research, University of Vienna. SUBJECTS: Fourteen juvenile swine received either an endotracheal tube (Group A) or a Combitube in esophageal position (Group B). INTERVENTIONS: In Part I of the study, epinephrine was administered during spontaneous beating of the heart; in Part II, epinephrine was administered during cardiopulmonary resuscitation, using a ten-fold higher dosage in Group B, respectively. MEASUREMENTS: Plasma epinephrine levels were measured 1, 2, 3, 5, 7, 10, 15, and 30 mins after application. Systolic arterial blood pressure and cardiac output in Part I, and end-tidal CO2 and coronary perfusion pressure in Part II were recorded. MAIN RESULTS: In Part I, increased levels of plasma epinephrine and systolic arterial pressure were maintained significantly longer in Group B when compared with Group A. In Part II, no significant differences between the groups were found with regard to plasma epinephrine levels and hemodynamic variables. CONCLUSION: Epinephrine applied via the esophageal lumen of the Combitube in a ten-fold higher dosage has similar effects on plasma epinephrine levels and hemodynamic variables compared to endotracheal administration.

Animals↗
PubMed2000

Mild resuscitative hypothermia to improve neurological outcome after cardiac arrest. A clinical feasibility trial. Hypothermia After Cardiac Arrest (HACA) Study Group.

BACKGROUND AND PURPOSE: Recent animal studies showed that mild resuscitative hypothermia improves neurological outcome when applied after cardiac arrest. In a 3-year randomized, prospective, multicenter clinical trial, we hypothesized that mild resuscitative cerebral hypothermia (32 degrees C to 34 degrees C core temperature) would improve neurological outcome after cardiac arrest. METHODS: We lowered patients' temperature after admission to the emergency department and continued cooling for at least 24 hours after arrest in conjunction with advanced cardiac life support. The cooling technique chosen was external head and total body cooling with a cooling device in conjunction with a blanket and a mattress. Infrared tympanic thermometry was monitored before a central pulmonary artery thermistor probe was inserted. RESULTS: In 27 patients (age 58 [interquartile range [IQR] 52 to 64] years; 7 women; estimated "no-flow" duration 6 [IQR 1 to 11] minutes and "low-flow" duration 15 [IQR 9 to 23] minutes; admitted to the emergency department 36 [IQR 24 to 43] minutes after return of spontaneous circulation), we could initiate cooling within 62 (IQR 41 to 75) minutes and achieve a pulmonary artery temperature of 33+/-1 degrees C 287 (IQR 42 to 401) minutes after cardiac arrest. During 24 hours of mild resuscitative hypothermia, no major complications occurred. Passive rewarming >35 degrees C was accomplished within 7 hours. CONCLUSIONS: Mild resuscitative hypothermia in patients is feasible and safe. A clinical multicenter trial might prove that mild hypothermia is a useful method of cerebral resuscitation after global ischemic states.

Brain↗
PubMed2000

Garlic extract (allium sativum) reduces migration of neutrophils through endothelial cell monolayers.

Leukocytes play an important role during inflammation. They migrate from intravascular spaces into tissues and attack micro-organisms. In a recent study, the inhibitory effects of the non-steroidal anti-inflammatory drug, ibuprofen, on leukocyte transmigration were demonstrated using an in vitro assay. Little is know about the cellular effects of garlic extracts (allium sativum). The aim of the current study was to investigate the influence of garlic extract on leukocyte migration through endothelial cell monolayers and thereby evaluate a possible role in inflammatory processes. Human umbilical endothelial cells were cultured on microporous membranes to make an endothelial cell monolayer (ECM). Freshly isolated neutrophils were used in a recently described migration assay. The amount of untreated neutrophils migrating through the untreated ECM was used as control and set at 100%. Neutrophils and/or ECM were pre-treated with garlic extract using moderate, as well as higher and lower concentrations. Moderate plasma concentrations garlic extract inhibited neutrophil migration through ECM significantly (64 +/- 5.8% SD; P < 0.05), when both cell types were treated, (a situation that may have clinical relevance). Treating either neutrophils or ECM alone showed significant reductions in migratory rate (neutrophils treated alone: 81 +/- 7.7% SD, p < 0.05; ECM alone: 70 +/- 6.7%, p < 0.05). Thus, garlic extract is identified as a potent inhibitor of leukocyte migration through endothelial cell monolayers. Treatment of both cell types has an additive effect. Endothelial cells seem to be more affected than neutrophils. Further investigations are necessary to understand the potential clinical consequences. During inflammation, neutrophils play an important role. They migrate rapidly from the vascular space into tissues to destroy invading micro-organisms. During migration through endothelial cell monolayers (ECM), neutrophils undergo morphologic changes from rounded, relatively smooth cells to elongated, ruffled cells with pseudopodia. Recently, the influence of the non-steroidal anti-inflammatory drug, ibuprofen, on leukocyte function was investigated using an in vitro double chamber migration assay that includes ECM. Garlic extract (allium sativum) is a widely used "over the counter" herbal preparation. The effect of garlic on lipid metabolism is well documented. Previous studies have examined the influence of the extract on leukocyte function, e.g. respiratory burst. The effect of garlic on thrombocyte aggregation has also been recently described as has an anti-fungal effect. To our knowledge, nothing is known about the effect of garlic leukocyte transmigration. Therefore, we aimed to examine the effects of garlic extract on leukocyte transmigration through ECM in an in-vitro cell co-culture system.

Allium↗
PubMed1999

Rapid, fluorescence-based assay for microtiter plates to test drug influences on neutrophil transmigration through endothelial cell monolayers.

Investigation of drug interactions between blood cells and endothelium is of high interest. The current study describes the development of a rapid fluorescence-based leukocyte transmigration system through endothelial cell monolayers for investigation of drug influences. To test the new assay, endothelial cells were cultured on microporous filters, pore size 3.0 microm, in 96-well-plates. Freshly isolated neutrophils were seeded on endothelial cell monolayers and transmigrated cells were measured after incubation for three hours. Migration of non-stimulated neutrophils through non-stimulated endothelial cell monolayer was used as control and set as 100%. The influence of the non-steroidal anti-inflammatory drug diclofenac was investigated. Assay precision tests were done using intraassay (within-day variability) and interassay (day-to-day variability) controls. Transmigration rate was decreased to 53 +/- 6.8% SD (diclofenac 0.7 microg/mL). Different concentrations showed a dose dependent effect (0.07 microg/mL: 97 +/- 9.5%, 7 microg/mL: 37 +/- 4.7%). Analysis of assay accuracy of the new 96-well-sized transmigration assay showed reliable results (coefficient of variation: intraassay 8.2 %; interassay 11.8%). In conclusion, this new, rapid, and sample saving 96-well-microtiter transmigration assay allows examination of drug influence on neutrophil migration through endothelial cell monolayers. Moreover, this assay can also be used for other cell-cell interactions.

Adult↗
PubMed1999

The green tea extract epigallocatechin gallate is able to reduce neutrophil transmigration through monolayers of endothelial cells.

Green tea is widely used in Asia and has also become popular in Western countries. The influence of green tea extracts on leukocytes is not well understood. Leukocytes play a crucial role in the process of inflammation. They migrate from the intravascular space into the tissue to attack micro-organisms. The aim of the current study was to investigate the influence of epigallocatechin gallate on leukocyte transmigration through endothelial cell monolayers and thereby evaluate its potential role in the inflammatory process. Human umbilical vein endothelial cells were cultured on microporous membranes to achieve a monolayer. Freshly isolated neutrophils from healthy subjects were measured with a migration assay. The amount of untreated neutrophils migrating through untreated endothelial cell monolayers was used as control and set as 100%. Neutrophils and/or endothelial cell monolayers were pre-treated with epigallocatechin gallate using relevant, as well as higher and lower concentrations. The relevant plasma concentration of epigallocatechin gallate was able to significantly inhibit neutrophil migration through endothelial cell monolayers (69 +/- 6.4% SD; p < 0.05 compared to control), when both cell types (leukocytes and endothelial cell monolayer) were treated. This is similar to the situation after resorption in-vivo. Treating either neutrophils or endothelial cell monolayers alone led to significant reductions in migratory response (only neutrophils treated: 86 +/- 8.1% SD, p < 0.05; only endothelial cell monolayers: 77 +/- 6.1%, p < 0.05). In conclusion, epigallocatechin gallate was identified as a potent inhibitor of leukocyte migration through endothelial cell monolayers. The treatment of both cell types showed an additive effect. Endothelial cells seem to be more affected than neutrophils. Further clinical investigations are necessary to understand the potential clinical consequences.

Catechin↗
PubMed1999

[Recollections of ventilated patients after a stay in the intensive care unit].

UNLABELLED: A review of the literature reveals only scarce data and observations concerning the recollections of patients treated in a intensive care unit, although intraoperative awareness under general anaesthesia has been extensively reported. In the present study we investigated the recollections of patients who had undergone artificial ventilation in intensive care units. METHODS: Fifty patients who had undergone mechanical ventilation in intensive care units at the University Hospital of Vienna were retrospectively interviewed in regard of their experience during the treatment. A score was used to quantify discomfort. RESULTS: All patients remembered having been treated at the intensive care unit. The most unpleasant experience was tracheal suctioning which was remembered by 60%. The next most unpleasant experience was extubation; 52% remembered this intervention. Eighty-four per cent of patients remembered the medical staff, 90% of them had confidence in them, 86% remembered the nursing staff and 91% had confidence in them. CONCLUSION: In spite of unpleasant memories of intensive care treatment, of which tracheal suctioning was perceived as most unpleasant, the majority of patients expressed a positive evaluation of their treatment at the intensive care unit.

Adult↗
PubMed1999

Influence of prothrombin complex concentrates on plasma coagulation in critically ill patients.

OBJECTIVE: To evaluate thrombogenicity of prothrombin complex concentrates (PCCs) in critically ill patients. DESIGN: Prospective clinical study. SETTING: Medical intensive care unit at a university hospital. PATIENTS: 16 consecutive patients suffering from acquired deficiencies of coagulation factors and with either overt bleeding from any site or a planned invasive procedure. INTERVENTIONS: 2000 factor IX units of PCCs intravenously. MEASUREMENTS AND RESULTS: Prothrombin time (PT), activated partial prothrombin time, fibrinogen, platelet count, plasma levels of coagulation factors II, V, VII, VIII, IX, X, antithrombin, protein C, thrombin-antithrombin complex (TAT), prothrombin fragment F(1+2), and the fibrin degradation product D-dimer were measured prior to and 1, 3, and 24 h after administration of PCCs. PT as well as coagulation factors II, VII, IX, and X, TAT, and F(1+2) showed a significant increase after administration of PCCs. All other parameters remained unchanged. CONCLUSIONS: Administration of PCCs induces thrombin generation. No evidence for induction of disseminated intravascular coagulation in biochemical terms could be found. When rapid correction of acquired coagulation factor disturbances is warranted, the use of PCCs seems reasonable, but the elevated risk of intravascular thrombus formation should be kept in mind.

Adult↗
PubMed1999

Oral contraceptives that contain ethinyl estradiol (0.035 mg) and cyproterone acetate (2 mg) inhibit leukocyte transmigration through endothelial cell monolayers.

OBJECTIVE: To investigate the influence of ethinyl estradiol and cyproterone acetate in oral contraceptives on leukocyte migration through endothelial cell monolayers. DESIGN: Experimental in vitro prospective study. SETTING: An academic research laboratory. INTERVENTION(S): Endothelial cells were cultured on microporous membranes to produce monolayers. Polymorphonuclear leukocytes were used in a previously described migration assay (n = 7). The amount of untreated polymorphonuclear leukocytes that migrated through untreated endothelial cell monolayers was used as a control and set at 100%. In addition, a leukocyte adhesion assay was used. MAIN OUTCOME MEASURE(S): Leukocyte adhesion to and transmigration through endothelial cell monolayers. RESULT(S): Ethinyl estradiol and cyproterone acetate inhibited the migration of polymorphonuclear leukocytes through endothelial cell monolayers significantly (67% +/- 6.4%) when both cell types were treated to simulate in vivo conditions. The adhesion assay produced similar results. CONCLUSION(S): Ethinyl estradiol and cyproterone acetate were identified as potent inhibitors of leukocyte migration through endothelial cell monolayers.

Cell Adhesion↗
PubMed1999

Dexamethasone inhibits leukocyte migration through endothelial cells towards smooth muscle cells.

Leukocyte interactions with endothelial cell monolayers (ECM) and smooth muscle cells (SMC) play an important role during inflammatory processes. Several studies describe an inhibitory effect of dexamethasone on polymorphonuclear leukocytes (PMNL), endothelial cell function, and interleukin-1 (IL-1) release. Aim of the current study was to investigate the influence of dexamethasone on leukocyte migration through an endothelial cell monolayer towards SMC-layers stimulated by tumor necrosis factor-alpha (TNF-alpha). Using a recently developed triple chamber migration system, SMC-layers were cultured on the bottom of a 24-well plate. On the upper surface of the first filter, ECM were cultured, the second filter was a collecting filter. The amount of leukocyte migration through ECM towards TNF-alpha-stimulated smooth muscle cell layers with and without dexamethasone-pretreatment was measured using a fluorescence technique. The pretreatment of SMC-layers with dexamethasone reduced the amount of leukocyte migration down to 92 +/- 8.8% (0.001 mM, p=n.s.), to 67 +/- 5.7% (0.01 mM, p<0.05), to 53 +/- 4.6% (0.1 mM, p<0.05), and to 41 +/- 5.0% (1 mM, p<0.05). In conclusion, dexamethasone treatment of smooth muscle cell layers inhibits leukocyte migration through ECM towards smooth muscle cell layers. The inhibition seems to be due to a decrease in IL-1 release. Treatment of all cell types, PMNL, endothelial cells, as well as smooth muscle cell layers, simulating an in-vivo situation, seems to have an additive effect.

Cell Culture Techniques↗
PubMed1999

No reduction in the sufentanil requirement of elderly patients undergoing ventilatory support in the medical intensive care unit.

The aim of the study was to test the hypothesis that the requirement of sufentanil is reduced in elderly patients when the opiate is primarily used to facilitate mechanical ventilation in a medical intensive care unit. A further aim was to study whether elderly patients developed withdrawal symptoms after discontinuing prolonged sufentanil administration. We have studied prospectively two groups of patients requiring mechanical ventilation for more than 96 h; group 1 age < 60 years (n = 316 or 68%) and group 2 age > 70 years (n = 150 or 32%). In all patients sufentanil and midazolam were administered continuously in order to facilitate ventilatory support. After an initial intravenous bolus injection of sufentanil 3.0-8.0 micrograms kg-1, the dosage was adjusted to the patients needs (0.75-1.0 microgram-1 kg-1 h) using a modified Ramsey score by accepting between 3b and 4a as the end point. The amount of sufentanil administered and side effects were recorded at 24-h intervals. Seventy-two hours following the start of sedation with sufentanil/midazolam the dose of sufentanil required for sedation increased significantly (P < 0.05) in both groups when compared with the first 24 h. There was no statistical difference between the two groups in sufentanil requirement at any time during the study. This suggests that tachyphylaxis develops to a similar degree in patients in both age groups. In addition, weaning in the elderly was characterized by a similar degree of withdrawal-like symptoms suggesting that independent of age, there are similar receptor related reactions once the opiate is withdrawn.

Aged↗
PubMed1999

Effect of anticoagulation on blood membrane interactions during hemodialysis.

BACKGROUND: Adequate anticoagulation is a precondition to prevent extracorporeal blood clotting and to improve biocompatibility during hemodialysis. In this study, we performed a morphologic analysis by using scanning electron microscopy to compare three modes of anticoagulation-conventional unfractionated heparin (UFH), low molecular weight heparin (LMWH; dalteparin sodium), or sodium citrate during hemodialysis-on membrane-associated coagulation activation. METHODS: Fifteen patients on regular hemodialysis therapy were investigated. Five patients received UFH, five patients LMWH, and five patients sodium citrate as an anticoagulant during a standardized hemodialysis protocol using a single-use polysulfone capillary dialyzer. Membrane-associated clotting was evaluated using a scanning electron microscope. A dialyzer clotting score was used for quantitative description of coagulation activation on membrane segments. RESULTS: Using UFH as an anticoagulant revealed the most pronounced cell adhesion and thrombus formation and the highest dialyzer clotting score (11.5 +/- 1.3 of a maximal 20 points). LMWH had a lower dialyzer clotting score than UFH (10.4 +/- 1.2 of 20 points). During the use of sodium citrate, a negligible thrombus formation and the lowest dialyzer clotting score (1.6 +/- 0.6 of 20 points, P < 0.05) were observed. CONCLUSION: The results of this investigation indicate that using sodium citrate as an anticoagulant during hemodialysis induces a lower activation of coagulation than both conventional and fractionated heparin, which might contribute to an improvement of biocompatibility of hemodialysis extracorporeal circulation.

Adult↗
PubMed1999

Hydroxyethyl starch reduces the chemotaxis of white cells through endothelial cell monolayers.

BACKGROUND: Polymorphonuclear leukocytes (PMNs) play a tremendous role during inflammatory processes. PMNs have to pass a monolayer of endothelial cells to migrate into the extravascular space. Hydroxyethyl starch (HES) is frequently used as a volume expander in critically ill patients. STUDY DESIGN AND METHODS: The aim of this study was to investigate whether HES influences the chemotaxis of PMNs through endothelial cell monolayers by using a test system that allows the simultaneous treatment of both cell types. Human umbilical endothelial cells were cultured on microporous membrane filters. PMNs were isolated and PMN chemotaxis was studied. RESULTS: The number of untreated PMNs that migrated through untreated endothelial cell monolayers in response to a chemoattractant was used as a control and set as 100 percent. In clinically relevant concentrations, HES was able to significantly decrease PMN chemotaxis through endothelial cell monolayers, showing a dose-dependent effect (0.1 mg/mL: 99.6 +/- 10.9%, p = NS compared to control; 1 mg/mL: 82.4 +/- 8.3%, p<0.05 compared to control; 10 mg/mL: 62.9 +/- 11.7%, p<0.05). In this assay, both cell types (PMNs and endothelial cells in the monolayer) were treated simultaneously, which simulated the clinical situation after an intravenous injection of HES. The treatment of one cell type, PMNs (89.6 +/- 8.8%, p<0.05) or endothelial cells in the monolayer (76.2 +/- 9.4%, p<0.05), suggests that the influence on endothelial cells is greater. CONCLUSION: HES is able to significantly reduce the chemotaxis of PMNs through endothelial cell monolayers. The possible clinical consequence of a moderate reduction in endothelium-mediated PMN chemotaxis in critically ill patients remains to be evaluated.

Adult↗
PubMed1999

Continuous infusion versus intermittent administration of meropenem in critically ill patients.

This prospective crossover study compared the pharmacokinetics of meropenem by continuous infusion and by intermittent administration in critically ill patients. Fifteen patients were randomized to receive meropenem either as a 2 g iv loading dose, followed by a 3 g continuous infusion (CI) over 24 h, or by intermittent administration (IA) of 2 g iv every 8 h (q8h). Each regimen was followed for a period of 2 days, succeeded by crossover to the alternative regimen for the same period. Pharmacokinetic parameters (mean +/- SD) of CI included the following: concentration at steady state (Css) was 11.9+/-5.0 mg/L; area under the curve (AUC) was 117.5+/-12.9 mg/L x h. The maximum and minimum serum concentrations of meropenem (Cmax, Cmin) and total meropenem clearance (CItot) for IA were 110.1+/-6.9 mg/L, 8.5+/-1.0 mg/L and 9.4+/-1.2 L/h, respectively. The AUC during the IA regimen was larger than the AUC during CI (P < 0.001). In both treatment groups, meropenem serum concentrations remained above the MICs for the most common bacterial pathogens. We conclude that CI of meropenem is equivalent to the IA regimen and is therefore suitable for treating critically ill patients. Further studies are necessary to compare the clinical effects of CI and IA in this patient group.

Adolescent↗
PubMed1999

Amoxycillin/clavulanic acid combinations increase transmigration of leucocytes through endothelial cell monolayers: endothelial cells play a key role.

Postoperative inflammation is still viewed as an unresolved problem. During inflammation, leucocytes play a tremendous role and migrate from intravascular spaces into the tissue to attack microorganisms. Different agents, e.g. anaesthetic drugs, are able to influence leucocyte recruitment. Previous studies have investigated the influence of amoxycillin on chemotaxis of leucocytes alone. The aim of our study was to examine the effect of amoxycillin/clavulanic acid (co-amoxiclav) on leucocyte migration through endothelial cell monolayers (ECMs). Human umbilical endothelial cells were cultured on microporous membranes, achieving a monolayer. Polymorphonuclear neutrophil leucocytes (PMNLs) were used in a migration assay. The numbers of untreated PMNLs migrating through untreated ECMs were used as control and set as 100%. PMNLs and/or ECMs were pretreated with co-amoxiclav using clinically relevant as well as higher and lower concentrations. Co-amoxiclav was able to increase PMNL migration through ECMs significantly (P<0.05) when both cell types were treated (291+/-18.7%). When PMNLs or ECMs were treated alone, it could be shown that ECMs were more affected than PMNLs. The greatest effect was shown when both cell types, PMNLs and ECMs, were treated. In conclusion, co-amoxiclav was identified as a potent drug to increase leucocyte transmigration through ECMs. ECMs were also critically involved. Co-amoxiclav also affects endothelial cells.

Amoxicillin-Potassium Clavulanate Combination↗
PubMed1999

The assessment of four different methods to verify tracheal tube placement in the critical care setting.

UNLABELLED: One of the most serious complications of conventional endotracheal intubation is unidentified placement of the tube in the esophagus. The aim of our study was to evaluate four different methods for immediate detection of the tube position: auscultation, capnographic determination of ETCO2, esophageal detection method (EDM) using a self-inflating bulb, and the transillumination method using a lighted stylet (Trachlight; Laerdal, Armonk, NY). Thirty-eight endotracheally intubated patients admitted to our medical intensive care unit were enrolled in the study. A second identical tube was inserted into the esophagus under laryngoscopic control. The endotracheal tube was then disconnected from the ventilator. Two blinded examiners, one experienced, the other inexperienced, determined the tube position within 30 s using one of the four methods. The order of the tubes tested and the methods used were randomized. In 130 of 152 examinations, both examiners correctly diagnosed the position of the tube. The wrong result was obtained by both examiners 4 times; only the experienced examiner was wrong 4 times, and only the inexperienced examiner was wrong 14 times. Using ETCO2, both examiners were correct in all cases. Auscultation showed an obvious relation to the examiner's experience: the experienced examiner was correct in all cases, the inexperienced examiner was correct in only 68% of cases. Using the self-inflating bulb, there were two wrong results of the experienced examiner and one wrong result of the inexperienced examiner. The transillumination technique was associated with a high error rate by both examiners (16% and 13%, respectively). Comparing all four methods showed that capnography is superior to auscultation (P = 0.0005) and to the Trachlight detection method (P = 0.0078). EDM was not statistically superior to auscultation and transillumination. Capnography was the most reliable method for rapid evaluation of tube position, followed by EDM, whereas auscultation and Trachlight did not seem to be of comparable value. Experience was a determining factor for auscultation. IMPLICATIONS: To prevent unidentified esophageal intubation, a serious complication in the critical care setting, four methods for detecting tube position were tested by two examiners (one experienced, the other inexperienced) in endotracheally intubated patients after insertion of a second tube into the esophagus.

Adult↗