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Biomedical subjects

F Esen

Publications and source records attributed to F Esen.

At least 19 recordsLinked to original sources
PubMed2006

Detrended fluctuation analysis of laser Doppler flowmetry time series: the effect of extrinsic and intrinsic factors on the fractal scaling of microvascular blood flow.

The relative contribution of extrinsic (central) and intrinsic (local) oscillatory mechanisms to the fractal scaling of blood flow in forearm cutaneous microcirculation is unclear. The aim of this study was to investigate the contributions of these mechanisms to the fractal properties of the blood flow signal by using their frequency spectrum in the analyses. To evoke local oscillatory components, acetylcholine (ACh) was iontophoresed into the forearm and cutaneous perfusion was measured by a laser Doppler flowmeter (LDF) at rest. Depending on the involved factors in ACh-induced vasodilatation, central, cardiac and respiratory, signals have also increasingly appeared in LDF. The detrended fluctuation analysis (DFA) of filtered LDF time series demonstrated that the LDF was fractal with three distinct scaling regions. Furthermore, the findings of the present study indicated that these regions are related to the frequency bands of well-known control systems of blood flow and were called cardiac, cardio-respiratory and local regions. The mean scaling exponent increased with vasodilatation in the cardiac region but decreased and even changed its sign in the cardio-respiratory region. Inhibition of a local vasodilator mechanism not only decreased the scaling exponent of the local region but also eliminated the effect of respiratory coupling on fractal scaling. These findings suggest that the scaling exponents might have a diagnostic value for detecting pathological dynamics in vascular beds.

Adult↗
PubMed2006

Effect of electromagnetic fields emitted by cellular phones on the latency of evoked electrodermal activity.

The widespread use of cellular phones raises the question of their possible adverse biological effects, especially on the central nervous system (CNS). Therefore, the authors examined the effect of electromagnetic fields emitted by cellular phones (CPEMFs) on the evoked neuronal activity of CNS relating to generation and representation of electrodermal activity (EDA), an index of sympathetic nervous system activity. EDA (skin resistance response; SRR) latency was lengthened approximately 200 ms with CPEMFs exposure irrespective of the head site next to mobile phone used. Hemispheric asymmetry of EDA-2 pathway, which is represented by shorter SRR latency in the right hand of the right hand responders, was also distorted with CPEMFs. Because the CNS regions including EDA-2 are also involved in tasks of motor timing and time estimation, delayed response in this neuronal network due to CPEMFs exposure may increase the response time of mobile phone users. Therefore, the findings point to the potential risks of mobile phones on the function of CNS and consequently, possible increase in the risk of phone-related driving hazards.

Adult↗
PubMed2006

Exogenous zinc improves blood fluidity but has no effect on the mechanisms of vascular response to acetylcholine iontophoresis in humans.

Recent findings in cellular signaling function of zinc through the mobilization intracellular calcium or by inducing ATP release suggest that extracellular zinc plays an important role in many physiological functions. However, such an extracellular signaling action of zinc for most cells is not known. Therefore, we investigated whether zinc plays any role in endothelium- dependent acetylcholine (ACh)-induced vasodilatation in microvascular beds. Transdermal iontophoresis was used to transport ACh through the forearm skin and cutaneous perfusion was measured using a laser Doppler flowmeter (LDF). Experiments were repeated using (1) zinc instead of ACh to test the effect of zinc ions alone and (2) concomitant iontophoresis of ACh and zinc to explore the effect of zinc on ACh-induced vasodilatation. Although zinc augments blood flow, curve-fitting to LDF signals indicate that zinc has no effect on the neural and endothelial component of ACh-induced vasodilatation. Additionally, no effect of Zn2+ on blood flow was found during its iontophoresis alone. Therefore, it is suggested from the Fourier analysis of LDF signals that the Zn+ might influence blood fluidity by its action on red blood cells deformability/ aggregability during a high-blood-flow condition, which might, in turn, decrease blood viscosity and improve blood flow in vivo.

Acetylcholine↗
PubMed2002

Early first trimester ultrasound examination. Is it really efficient in the clinical management of the pregnancy?

OBJECTIVE: This is a retrospective study accomplished to determine the efficiency of the first trimester ultrasound examination especially when performed on elective conditions. MATERIALS AND METHOD: The records of patients who had undergone early first trimester transvaginal ultrasound in Obstetrics and Gynecology Department of Cerrahpasa School of Medicine, Istanbul University between from January 1999 to December 2000 were reviewed. The records of 426 patients were eligible for the analysis. The age, parity, gestational week that the ultrasound performed, the complaint on appliance, the features visible on the ultrasound were noted. The patients were divided into two groups: patients without any complaint (Group 1) and patients applied with any complaint (Group 2). The prognosis of the pregnancy was determined through the follow-up. On the statistical analysis, chi-square test, student-t test, Pearson correlation analysis and multiple linear regression analysis were utilized. RESULTS: In group 1, 79% of examinations were normal whereas the rate of normal ultrasound was 50% in group 2. The difference between the groups was statistically significant (p=0.000). On group 1, 7 subsequent abortions, 7 missed abortions and one case of mole hydatiform were identified (7.6%). When the patient applied with a complaint, ultrasound examination revealed abnormal findings that enabled to reach an accurate diagnosis in 29.9% of these patients. 50 abortions (inevitable or incomplete), 13 missed abortions, 3 ectopic pregnancies and 2 mole hydatiform were diagnosed. The difference between the two groups according to ability to reach a diagnosis on the initial ultrasound was statistically significant (p=0.000). CONCLUSION: The value of ultrasound examination before the 10th weeks of pregnancy is not validated when the patient has no complaint even if it appears as the most powerful mean to assess the accurate gestational age and observing fetal cardiac activity is the best prognostic variable for the outcome of the fetus.

Adult↗
PubMed2002

Prognosis of patients with positive screening but negative diagnostic test for gestational diabetes.

OBJECTIVE: This is a retrospective study that is designed to investigate the prognosis of the patients with abnormal diabetes screening test and a negative 100 g oral glucose tolerance test that is accepted as the diagnostic test for gestational diabetes mellitus (GDM). MATERIALS AND METHOD: The records of 281 pregnant patients were reviewed. The data of the patients divided into groups with normal diabetes screening (1 h/50 g oral glucose tolerance test) and abnormal diabetes screening. The patients with abnormal diabetes screening were further divided into all values normal in 100 g Oral glucose tolerance test (OGTT), one value abnormal in 100 g OGTT and GDM subgroups. The prognosis of these patients was reanalyzed concerning the complications that may be attributed to glucose intolerance. RESULTS: Abnormal diabetes screening test was detected in 89 patients (31.6%) and 14 cases were diagnosed as GDM (4.9%). The data of 9 patients were not suitable to analyze. In 31 cases out of 80 (38.75%), an obstetric complication was detected. The rate of similar complications was 27.0% (52/192) in the control group. The difference in the rate of complications was not statistically significant (p>0.05). When the patients with one value abnormal in 100 g OGTT, were further evaluated, the complication rates were 3/9 (33.3%) for the 1st hour abnormal patients, 1/1 for the 2nd hour abnormal patients and 1/1 for the 3rd hour abnormal patients. When the values of 100 g OGTT were compared in complicated and uncomplicated cases, the difference between the groups was not statistically significant (p>0.05). CONCLUSION: 100 g OGTT is the universal diagnostic test for GDM. There is a major subgroup of patients whose screening positive but diagnostic test (100 g OGTT) negative. These patients seem to be prone to develop obstetric complications related to glucose intolerance but there is not a proper means to detect these patients in clinical practice.

Adult↗
PubMed2002

Handwashing frequencies in an intensive care unit.

As most nosocomial infections are thought to be transmitted by the hands of healthcare workers, handwashing is considered the single most important intervention to prevent nosocomial infections. However, previous studies have shown that handwashing practices are poor, especially among medical personnel. The objective of this study was to assess the rate of handwashing among intensive care unit (ICU) healthcare personnel, and then to propose realistic suggestions so that hand hygiene' could be performed at an optimal level. To achieve this, each healthcare worker in the ICU of Istanbul Medical Faculty was observed directly, and, a comprehensive microbiological investigation was carried out among personnel and of the inanimate environment. The frequency of handwashing was low; 12.9% among medical personnel. Moreover, there was a widespread contamination in the ICU and 28.1% of the healthcare workers were carriers for methicillin-resistant Staphylococcus aureus (MRSA). The factors that contributed to low compliance of handwashing protocols were: a low staff to patient ratio, excessive use of gloves and deficiencies in the infra-structure of ICU. In heavy workload conditions, alcoholic handrub solutions for quick hand decontamination can be considered as an alternative to handwashing.

Environmental Microbiology↗
PubMed2002

Hemispheric modulatory influences on skin resistance response latency: unilateral stimulation, bilateral recording.

In order to evaluate the bilateral asymmetries in evoked electrodermal activity (EDA) and the use of EDA parameters as indices of relative hemispheric activation, skin resistance level (SRL), skin resistance response (SRR), and the SRR latency (L) were examined in 25 right-handed male subjects. We used bilateral recording with a unilateral stimulation (auditory click/patellar tendon tap) to assess the asymmetries of EDA variables related to the side of stimulation and to handedness. Although no significant asymmetry in C = SRRmax/SRL ratio was found, significant differences in latency were observed. Ipsilateral responses were 100 ms faster than contralateral responses for auditory stimulus, a result that can be explained in terms of contralateral delay of neuronal communication on EDA-l pathway. Response latency to reflex-motor activation was 60-100 ms shorter in the dominant hand, regardless of the stimulation site used. This result indicates that the reaction time of the EDA-2 pathway of the left hemisphere was shorter than the right for right-handed subjects. It is concluded that there is hemispheric asymmetry on EDA-2 pathway and that this asymmetry appears to be dependent on the preferred dexterity. These results have implications for the influence of both central and peripheral factors on EDA laterality and principally on laterality of response amplitude. Further, there is no single cortical mechanism modulating the asymmetries in the latency of this response.

Acoustic Stimulation↗
PubMed2002

Evaluation of effects of magnesium sulphate in reducing intraoperative anaesthetic requirements.

BACKGROUND: The present randomized, placebo-controlled, double-blind study was designed to assess the effect of peroperatively administered i.v. magnesium sulphate on anaesthetic and analgesic requirements during total i.v. anaesthesia. METHODS: Eighty-one patients (36 women, 45 men) undergoing elective spinal surgery were included in one of two parallel groups. The magnesium group received magnesium sulphate 30 mg kg(-1) as a bolus before induction of anaesthesia and 10 mg kg(-1) h(-1) by continuous i.v. infusion during the operation period. The same volume of isotonic solution was administered to the control group. Anaesthesia was maintained with propofol (administered according to the bispectral index) and remifentanil (adjusted according to heart rate and arterial blood pressure) infusions. RESULTS: A significant reduction in hourly propofol consumption was observed with magnesium administration. For example, the mean infusion rate of propofol in the second hour of the operation was 7.09 mg kg(-1) h(-1) in the control group vs 4.35 mg kg(-1) h(-1) in the magnesium group (P<0.001). The magnesium group required significantly less remifentanil (P<0.001) and vecuronium (P<0.001). No side-effects were observed with magnesium administration. CONCLUSION: The administration of magnesium led to a significant reduction in the requirements for anaesthetic drugs during total i.v. anaesthesia with propofol, remifentanil and vecuronium.

Anesthesia, Intravenous↗
PubMed2002

Reliability of procalcitonin as a severity marker in critically ill patients with inflammatory response.

Procalcitonin (PCT) is increasingly recognised as an important diagnostic parameter in clinical evaluation of the critically ill. This prospective study was designed to investigate PCT as a diagnostic marker of infection in critically ill patients with sepsis. Eighty-five adult ICU patients were studied. Four groups were defined on the basis of clinical, laboratory and bacteriologic findings as systemic inflammatory response syndrome (SIRS) (n = 10), sepsis (n = 16), severe sepsis (n = 18) and septic shock (n = 41). Data were collected including C-reactive protein (CRP), PCT levels and Sequential Organ Failure Assessment and Acute Physiology and Chronic Health Evaluation II scores on each ICU day. PCT levels were significantly higher in patients with severe sepsis and septic shock (19.25 +/- 43.08 and 37.15 +/- 61.39 ng/ml) than patients with SIRS (0.73 +/- 1.37 ng/ml) (P < 0.05 for each comparison). As compared with SIRS patients, plasma PCT levels were significantly higher in infected patients (21.9 +/- 47.8 ng/ml), regardless of the degree of sepsis (P < 0.001). PCT showed a higher sensitivity (73% versus 35%) and specificity (83% versus 42%) compared to CRP in identifying infection as a cause of the inflammatory response. Best cut-off levels were 1.31 ng/ml for PCT and 13.9 mg/dl for CRP. We suggest that PCT is a more reliable marker than CRP in defining infection as a cause of systemic inflammatory response.

APACHE↗
PubMed2001

Time required for partial pressure of arterial oxygen equilibration during mechanical ventilation after a step change in fractional inspired oxygen concentration.

OBJECTIVE: To determine the time required for the partial pressure of arterial oxygen (PaO2) to reach equilibrium after a 0.20 increment or decrement in fractional inspired oxygen concentration (FIO2) during mechanical ventilation. SETTING: A multi-disciplinary ICU in a university hospital. PATIENTS AND METHODS: Twenty-five adult, non-COPD patients with stable blood gas values (PaO2/FIO2 > or = 180 on the day of the study) on pressure-controlled ventilation (PCV). Following a baseline PaO2 (PaO2b) measurement at FIO2 = 0.35, the FIO2 was increased to 0.55 for 30 min and then decreased to 0.35 without any other change in ventilatory parameters. Sequential blood gas measurements were performed at 3, 5, 7, 9, 11, 15, 20, 25 and 30 min in both periods. The PaO2 values measured at the 30th min after a step change in FIO2 (FIO2 = 0.55, PaO2[55] and FIO2 = 0.35, PaO2[35]) were accepted as representative of the equilibrium values for PaO2. Each patient's rise and fall in PaO2 over time, PaO2(t), were fitted to the following respective exponential equations: PaO2b + (PaO2[55]-PaO2b)(1-e-kt) and PaO2[55] + (PaO2[35]-PaO2[55])(e-kt) where "t" refers to time, PaO2[55] and PaO2[35] are the final PaO2 values obtained at a new FIO2 of 0.55 and 0.35, after a 0.20 increment and decrement in FIO2, respectively. Time constant "k" was determined by a non-linear fitting curve and 90% oxygenation times were defined as the time required to reach 90% of the final equilibrated PaO2 calculated by using the non-linear fitting curves. RESULTS: Time constant values for the rise and fall periods were 1.01 +/- 0.71 min-1, 0.69 +/- 0.42 min-1, respectively, and 90% oxygenation times for rises and falls in PaO2 periods were 4.2 +/- 4.1 min-1 and 5.5 +/- 4.8 min-1, respectively. There was no significant difference between the rise and fall periods for the two parameters (p > 0.05). CONCLUSION: We conclude that in stable patients ventilated with PCV, after a step change in FIO2 of 0.20, 5-10 min will be adequate for obtaining a blood gas sample to measure a PaO2 that will be representative of the equilibrium PaO2 value.

Adult↗
PubMed2001

[The effect of pentaglobin therapy on prognosis in patients with severe sepsis].

This study was designed to assess the effects of polyclonal immunoglobulin administration on septic shock incidence and prognosis in patients with severe sepsis. Patients with severe sepsis were randomly allocated into two groups. One group (n = 21) received 5 ml/kg/day IgM enriched immunoglobulin preparation (Pentaglobin) for 3 days. Other group did not receive immunoglobulins (n = 18). Simplified Organ Failure Assessment (SOFA) scores, leucocyte count, duration of mechanical ventilation, ICU stay, duration of severe sepsis did not show significant differences between the groups, as regards to septic shock incidence and mortality. However, a significant decrease in procalcitonin levels were detected only in patients who received pentaglobin (p = 0.001). Mortality rate was 5/21 (23.8%) in pentaglobin group and 5/18 (27.7%) in the control group. Although pentaglobin therapy could not achieve a statistically significant improvement in septic shock occurrence and mortality, the constant reduction in procalcitonin levels indicated the beneficial effects of immunotherapy on the severity of inflammatory response to infection in severe sepsis.

APACHE↗
PubMed2000

Risk factors for early-onset, ventilator-associated pneumonia in critical care patients: selected multiresistant versus nonresistant bacteria.

BACKGROUND: Ventilator-associated pneumonia is the leading nosocomial infection in critically ill patients. The frequency of ventilator-associated pneumonia caused by multidrug-resistant bacteria has increased in recent years, and these pathogens cause most of the deaths attributable to pneumonia. The authors, therefore, evaluated factors associated with selected multidrug-resistant ventilator-associated pneumonia in critical care patients. METHODS: The authors prospectively recorded potential risk factors at the time of intensive care unit admission. An endotracheal aspirate was obtained in all patients who met clinical criteria for pneumonia. Patients were considered to have ventilator-associated pneumonia only when they met the clinical criteria and aspirate culture was positive for bacteria 48 h or more after initiation of mechanical ventilation. Pediatric patients were excluded. Adult patients with ventilator-associated pneumonia were first grouped as "early-onset" (< 5 days) and "late-onset," determined by episodes of ventilator-associated pneumonia, and then, assigned to four groups based on the bacteria cultured from their tracheal aspirates: Pseudomonas aeruginosa, Acinetobacter baumanii, methicillin-resistant staphylococci, and all others. The first three bacteria were considered to be multidrug resistant, whereas the others were considered to be antibiotic susceptible. Potential risk factors were evaluated with use of univariate statistics and multivariate regression. RESULTS: Among 486 consecutive patients admitted during the study, 260 adults underwent mechanical ventilation for more than 48 h. Eighty-one patients (31%) experienced 99 episodes of ventilator-associated pneumonia, including Pseudomonas(33 episodes), methicillin-resistant staphylococci (17 episodes), Acinetobacter(9 episodes), and nonresistant bacteria (40 episodes). Sixty-six of these episodes were early onset and 33 episodes were late onset. Logistic regression analysis identified three factors significantly associated with early-onset ventilator-associated pneumonia caused by any one of the multidrug-resistant bacterial strains: emergency intubation (odds ratio, 6.4; 95% confidence interval, 2.0-20.2), aspiration (odds ratio, 12.7; 95% confidence interval, 2.4-64.6), and Glasgow coma score of 9 or less (odds ratio, 3.9; 95% confidence interval, 1.3-11.3). A. baumanii-related pneumonia cases were found to be significantly associated with two of these factors: aspiration (odds ratio, 14.2; 95% confidence interval, 1.5-133.8) and Glasgow coma score (odds ratio, 6.0; 95% confidence interval, 1.1-32.6). CONCLUSIONS: The authors recommend that patients undergoing emergency intubation or aspiration or who have a Glasgow coma score of 9 or less be monitored especially closely for early-onset multidrug-resistant pneumonia. The occurrence of aspiration and a Glasgow coma score of 9 or less are especially associated with pneumonia caused by A. baumanii.

Adult↗
PubMed2000

[Percutaneous endoscopic gastrostomy in the ICU].

Aspiration pneumonia due to gastroesophageal reflux is a frequent complication in ICU. The most commonly chosen method for long-term enteral access is gastrostomy and this method also reduces the risk of aspiration and shortens the hospital stay. We evaluated 31 patients in whom PEG was performed between 1997-98 in our unit. Indication of PEG was long-term ICU stay and coma which necessitate long term enteral nutrition. Mean age of our patients were 60.5((19.4). We evaluated the aspiration by clinical inspection. Aspiration and interruption of feeding was observed 1.57 ((1.43) times before PEG and 0.67 ((0.73) times after PEG. Further more positive tracheal aspirate culture were seen 3.14 ((1.95) times before PEG and 1.52 ((1.47) times after PEG.

Critical Care↗
PubMed1998

Pituitary dimensions and volume measurements in pregnancy and post partum. MR assessment.

PURPOSE: Our purpose was to clarify and further characterize the changes in height, length, width, volume, and shape in the normal pituitary gland and in width in the infundibulum during pregnancy and the first 6 months post partum. MATERIAL AND METHODS: Cranial MR imaging was performed in 78 women who were pregnant in the second or third trimester or who were post partum, and in 18 age-matched control subjects who were not pregnant. Volume measurements were performed in 2 ways; volume 1=1/2 x height x length x width; and volume 2=area (measured by trackball) x slice thickness. RESULTS: Gland volume, height, width, length, and convexity, and infundibular width increased during pregnancy. The highest values were seen during the 3 days immediately post partum. When compared with volunteers, volumes 1 and 2 showed the largest increase (120%) among the parameters. Gland height showed the best correlation (r=0.94, p<0.00001) with gestational age. The mean height of the gland was 8.76 mm in the third trimester. None of the pregnant women had a gland height of above 10 mm during pregnancy. Only 2 subjects had gland heights of 10.04 and 10.2 mm during the 0-3 days post partum. After this first post-partum period of 3 days, the gland size, shape, and volume and the infundibular width returned to normal within 6 months. CONCLUSION: The pituitary gland enlarges in three dimensions throughout pregnancy. During pregnancy, the volume of the gland shows the highest percentage of increase compared to its length, height, and width. The maximum height of the gland does not exceed 10 mm during pregnancy but it may exceed 10 mm during the 3 days immediately post partum.

Adolescent↗
PubMed1997

Electrodermal activity in patients with Parkinson's disease.

Peripheral sympathetic activity was investigated in 25 Parkinson's disease (PD) patients and 27 healthy subjects by measuring the skin resistance level (SRL) and skin resistance response (SRR) at the palm of the hand during rest, auditory stimulation and patellar tendon tapping. Blood flow to the hand was also monitored. Normal responses were obtained from all the 27 healthy subjects with both stimuli. All but one of the 25 PD patients responded to sound, six patients failed to respond to patellar tendon tapping and one patient failed to respond to both stimuli. The SRRs (when detectable) of PD patients were always smaller in amplitude than those of normal subjects. It was also observed that while an electrodermal response was present, no vasomotor response could be elicited by either stimulus in some patients. The opposite was true in some other patients. When response latencies were evaluated, it was found that although the mean latency of SRRs evoked by tendon taping was shorter than the mean latency of responses to auditory stimuli in normal subjects, this was not the case in PD patients. SRR mean latency to patellar tendon tapping was significantly longer in PD patients compared with that in normal subjects. Mean latencies of responses to auditory stimuli were the same for both normal subjects and patients. The ratio of the SRR amplitude to SRL (i.e. relative change in SRL) during both types of stimulation was significantly smaller in PD patients than in normal subjects. All the above findings were also true when blood flow to the tissue was interrupted briefly. These findings support the conjecture that the abnormal peripheral sympathetic neural responses associated with PD may arise from a functional disorder in the basal ganglia that influence the efferent autonomic pathway, from impairment of the intermediolateral column of the spinal cord, and possibly from cognitive deficits.

Acoustic Stimulation↗
PubMed1997

Comparison of pressure- and flow-triggered pressure-support ventilation on weaning parameters in patients recovering from acute respiratory failure.

OBJECTIVE: To compare the effects of pressure- and flow-triggered pressure-support ventilation on weaning parameters during recovery from acute respiratory failure. DESIGN: Prospective, randomized, clinical trial. SETTING: Intensive care unit in a university hospital. PATIENTS: Sixteen orotracheally intubated adult patients recovering from acute respiratory failure of various etiologies, without chronic obstructive pulmonary disease. INTERVENTIONS: Randomized application of pressure- and flow-triggered pressure-support ventilation at 100% and 75% ventilatory support levels in each triggering system. A total of four conditions were applied for 30 mins each in all patients. MEASUREMENTS AND MAIN RESULTS: Ventilatory, respiratory, and hemodynamic data were measured. For the measurement of weaning parameters, pressure and volume signals were directed to a computerized respiratory monitor by means of an esophageal probe and a flow sensor between the "Y" piece of the ventilatory circuit and the endotracheal tube. During both pressure-triggered (trigger sensitivity of -1 cm H2O) and flow-triggered (trigger sensitivity of 0.7 to 2.0 L/min) pressure-support ventilation with a ventilator, peak airway pressures were applied so as to decrease the work of breathing performed by the patient to zero (full ventilatory support). Partial ventilatory support was applied at 75% of the peak airway pressures achieved during full ventilatory support with each triggering system. A total of four experimental conditions were evaluated at identical FiO2 and positive and-expiratory pressure levels during pressure-support ventilation in each patient. Total ventilation volumes, arterial blood gas data, and hemodynamics did not differ among the four experimental conditions. During partial ventilatory support, the work of breathing, rapid shallow breathing index, and esophageal pressure increased significantly with both triggering systems when compared with data obtained at full ventilatory support. The mean data for the weaning parameters during the condition of partial ventilatory support were comparable between pressure- and flow-triggered pressure-support ventilation (i.e., 0.38 +/- 0.24 vs. 0.42 +/- 0.26 joule/L for work of breathing, 2.6 +/- 1.6 vs. 3.3 +/- 1.7 cm H2O for tracheal occlusion pressure, and 40.2 +/- 12.9 vs. 50.4 +/- 18.3 breaths/min/L for rapid shallow breathing index, respectively). CONCLUSIONS: The application of either a pressure- or flow-triggered system during pressure-support ventilation with the ventilator did not significantly affect short-term changes in gas exchange, respiratory mechanics, and inspiratory workload in patients recovering from acute respiratory failure of various etiologies without chronic obstructive pulmonary disease.

APACHE↗