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J Takala

Publications and source records attributed to J Takala.

At least 55 records · Page 3Linked to original sources
PubMed2000

Effect of positive end-expiratory pressure on splanchnic perfusion in acute lung injury.

OBJECTIVE: To evaluate the acute effects of an increased positive end-expiratory pressure (PEEP) on splanchnic tissue perfusion. DESIGN: Clinical prospective study. SETTING: Intensive care unit in a university clinic. PATIENTS: Six patients with severe acute lung injury (ALI) requiring mechanical ventilation. All patients had bilateral infiltrates in chest X-ray, PaO2/FiO2 < 200 mmHg and stable hemodynamics without vasoactive drugs. INTERVENTIONS: PEEP was increased by 5 cmH2O from a clinically selected PEEP level (8/6-11 cmH2O) up to (13/10-14 cmH2O) followed by a return to baseline. MEASUREMENTS AND MAIN RESULTS: Splanchnic blood flow was measured using primed continuous infusion of indocyanine green dye with hepatic venous sampling and systemic hemodynamics by routine monitoring. In addition, we estimated gastric mucosal-arterial PCO2 difference and splanchnic lactate/pyruvate exchange. After a baseline measurement, PEEP was increased. After 60 min all measurements were repeated. PEEP was returned to the baseline level and a third measurement followed. PEEP had no effect on cardiac index (baseline I: 3.2/6.1-2.5 l/min/m2; PEEP: 3.3/5.7-2.3 l/min/m2; baseline II: 3.4/6.0-2.5 l/min/m2); neither did PEEP have any effect on splanchnic blood flow (baseline I: 0.91/1.39-0.62 l/min/m2; PEEP: 1.04/1.75-0.54 l/min/m2; baseline II: 1.07/1.42-0.68 l/min/m2, respectively) or perfusion (gastric mucosal-arterial PCO2 difference baseline I: 2.1/12.8-0.6 kPa; PEEP: 1.7/14.5-0.7 kPa; baseline II: 1.7/8.8-0.1 kPa; lactate uptake baseline I: 0.5/1.1-0.3 mmol/min/m2; PEEP: 0.4/1.0-0.3 mmol/min/m2; baseline II: 0.5/0.9-0.3 mmol/min/m2; hepatic venous lactate/pyruvate baseline I: 9.7/10.6-5.7; PEEP: 9.7/14.2-6.4; baseline II: 8.4/12.4-7.3; respectively). CONCLUSION: PEEP by itself does not have a consistent effect on splanchnic blood flow and metabolism when cardiac index is stable and patients are ventilated within the linear part of the pv curve.

Acute Disease↗
PubMed2000

Evaluation of a new module in the continuous monitoring of respiratory mechanics.

OBJECTIVE: Bedside monitoring of respiratory mechanics facilitates the use of lung protective ventilation in acute lung injury (ALI). We evaluated a new clinical monitor of respiratory mechanics. DESIGN: Prospective, in vitro and in vivo study. SETTING: University hospital. PATIENTS: Measurements were done using a lung model and in patients after cardiac surgery (n = 10) and in patients with ALI (n = 10). INTERVENTIONS AND MEASUREMENTS: The monitor provides continuous monitoring of pressure, flow and volume waveform and loop data, and automatically collected variables of respiratory mechanics. Breath-by-breath respiratory mechanics data and the automated variables obtained with the new monitor were compared with flow and pressure reference data. RESULTS: Waveform data comparison showed errors of less than 5% for most variables. Automatically recorded respiratory pressures and volumes showed good agreement within clinical standards when compared to reference (errors from 2.5% to 6.2%). Automatically recorded derived variables present poor agreement (errors from 8.1% to 158.3%). CONCLUSIONS: The waveform data of the new monitor is accurate. The value of the automatically derived variables is limited by the fact that inspiratory plateau pressure and plateau compliance have no direct physiological meaning. Nevertheless, in clinical monitoring much information can be derived from the waveform signals alone and from pressure-volume and flow-volume loops. These facilitate monitoring changes in respiratory mechanics in the ALI patient.

Adult↗
PubMed2000

Acute renal failure in the ICU: risk factors and outcome evaluated by the SOFA score.

OBJECTIVES: To describe risk factors for the development of acute renal failure (ARF) in a population of intensive care unit (ICU) patients, and the association of ARF with multiple organ failure (MOF) and outcome using the sequential organ failure assessment (SOFA) score. DESIGN: Prospective, multicenter, observational cohort analysis. SETTING: Forty ICUs in 16 countries. PATIENTS: All patients admitted to one of the participating ICUs in May 1995, except those who stayed in the ICU for less than 48 h after uncomplicated surgery, were included. After the exclusion of 38 patients with a history of chronic renal failure requiring renal replacement therapy, a total of 1411 patients were studied. MEASUREMENTS AND RESULTS: Of the patients, 348 (24.7%) developed ARF, as diagnosed by a serum creatinine of 300 micromol/l (3.5 mg/dl) or more and/or a urine output of less than 500 ml/day. The most important risk factors for the development of ARF present on admission were acute circulatory or respiratory failure; age more than 65 years, presence of infection, past history of chronic heart failure (CHF), lymphoma or leukemia, or cirrhosis. ARF patients developed MOF earlier than non-ARF patients (median 24 vs 48 h after ICU admission, p < 0.05). ARF patients older than 65 years with a past history of CHF or with any organ failure on admission were most likely to develop MOF. ICU mortality was 3 times higher in ARF than in other patients (42.8% vs 14.0%, p < 0.01). Oliguric ARF was an independent risk factor for overall mortality as determined by a multivariate regression analysis (OR = 1.59 [CI 95%: 1.23-2.06], p < 0.01). Infection increased the risk of death associated with all factors. Factors that increased the ICU mortality of ARF patients were a past history of hematologic malignancy, age more than 65 years, the number of failing organs on admission and the presence of acute cardiovascular failure. CONCLUSION: In ICU patients, the most important risk factors for ARF or mortality from ARF are often present on admission. During the ICU stay, other organ failures (especially cardiovascular) are important risk factors. Oliguric ARF was an independent risk factor for ICU mortality, and infection increased the contribution to mortality by other factors. The severity of circulatory shock was the most important factor influencing outcome in ARF patients.

Acute Kidney Injury↗
PubMed2000

IBIS data library: clinical description of the Finnish database. Improved Monitoring for Brain Dysfunction during Intensive Care and Surgery.

Improved monitoring of brain function in intensive care and surgery is a project aiming to develop methods of biosignal processing and interpretation, in order to characterise critical events during anaesthesia and cardiac surgery, effect of anaesthesia regimen, neurophysiological findings of different sedation levels, arousal from post-anaesthesia sedation, post-cardiopulmonary bypass brain dysfunction and early brain dysfunction in patients with multiple organ failure. A data library was collected in the three participating hospitals. This is a description of the data library from the University Hospital of Kuopio, Finland, which includes data from 40 patients after cardiac surgery and from seven patients with multiple organ dysfunction. This project demonstrates that active neuromonitoring can be performed in the intensive care unit without interference with the normal treatment and care. The presented database may serve other scientific workers as a reference for a typical spectrum of perioperative data with respect to severity of disease, length of cardiopulmonary bypass, postoperative levels of sedation and length of hospital stay in cardiac surgery patients, and for types of diseases and outcome in patients with multiple organ dysfunction.

Adult↗
PubMed2000

Detection of artifacts in monitored trends in intensive care.

In intensive care, decision-making is often based on trend analysis of physiological parameters. Artifact detection is a pre-requisite for interpretation of trends both for clinical and research purposes. In this study, we developed and tested three methods of artifact detection in physiological data (systolic, mean and diastolic artery and pulmonary artery pressures, central venous pressure, and peripheral temperature) using pre-filtered physiological signals (2-min median filtering) from 41 patients after cardiac surgery. These methods were: (1) the Rosner statistic; (2) slope detection with rules; and (3) comparison with a running median (median detection). After tuning the methods using data from 20 randomly chosen patients, the methods were tested using the data from the remaining patients. The results were compared with those obtained by manual identification of artifacts by three senior intensive care unit physicians. Out of an average of 22,480 data points for each variable, the three observers labelled 0.98% (220 data points) as artifacts. The inter-observer agreement was good. The average (range) sensitivity for artifact detection in all variables in the test database was 66% (33-92%) for the Rosner statistic, 64% (24-98%) for slope detection and 72% (41-98%) for median detection. All methods had a high specificity (> or = 94%). Slope detection had the highest mean positive prediction rate (53%; 21-85%). When the performance was measured by the cost function, slope detection and running median performed equally well and were superior to Rosner statistics for systemic arterial and central venous pressure and peripheral temperature. None of the methods produced acceptable results for pulmonary artery pressures. We conclude that median filtering of physiological variables is effective in removing artifacts. In post-operative cardiac surgery patients, the remaining artifacts are difficult to detect among physiological and pathophysiological changes. This makes large databases for tuning artifact algorithms mandatory. Despite these limitations, the performance of running median and slope detection were good in selected physiological variables.

Algorithms↗
PubMed2000

Single sweep analysis of event related auditory potentials for the monitoring of sedation in cardiac surgery patients.

Event-related potentials (ERPs) from the auditory system were investigated in 28 post-operative cardiac patients in order to assess their relevance in the monitoring of patient sedation level. Midazolam (17 patients) and propofol (11 patients) were the sedative agents used. The auditory ERP components of N100 (HAB100) and mismatch negativity (MMN) were considered. A single sweep method based on the AutoRegressive with eXogenous input (ARX) model, which is able to enhance the evoked responses to each single stimulus, was used to process each sweep and to compute traditional parameters on a sweep-by-sweep basis. Differences in the measured parameters were related to variations in the patient sedation levels classified through Ramsay score. Significant differences (P<0.05) in both MMN and HAB100 parameters were found between light sedation (LS) and deep sedation (DS) levels.

Aged↗
PubMed2000

Prioritization attitudes among doctors and nurses examined by a scenario method.

OBJECTIVES: To investigate doctors' and nurses' attitudes toward 14 potential prioritization criteria. METHODS: This study was performed by using the random paired scenario method. The respondents received a questionnaire with 12 pairs of scenarios, imaginary patient cases, each of which contained two to three different prioritization criteria (e.g., child, old patient, poor patient). Respondents were asked which one of each scenario pair they would choose if only one patient could be treated. The scenarios were randomly put into 30 different questionnaire sets. There was a random selection of 241 doctors and 151 nurses in Finland, with response rates of 60.3% and 50.3%, respectively. RESULTS: Doctors prioritized young patients, severe disease, expensive treatments and posteriorized (negatively prioritized) demented or institutionalized patients, and patients having a self-caused disease. Children were strongly prioritized, even over serious diseases. Expensive treatments appeared to be favored by doctors, and this result cannot be explained by severity of disease. Nurses' attitudes were similar to those of doctors. CONCLUSIONS: Children were strongly prioritized. Elderly persons were posteriorized if they had dementia or were living in institutions. Patients having a self-caused disease are posteriorized, more often by nurses than by doctors.

Adult↗
PubMed2000

The effect of sedation on weaning following coronary artery bypass grafting: propofol versus oxycodone-thiopental.

BACKGROUND: Propofol has been advocated for sedation in intensive care because of superior recovery characteristics. We hypothesised that the use of two totally different sedation methods after coronary artery bypass grafting should result in differences not only in extubation time, but also in breathing pattern and gas exchange during weaning and after extubation. METHODS: Thirty patients participated in this randomised and controlled study. We used propofol infusion and oxycodone-thiopental bolus dosage, titrated to sedation level 4 or 5 according to Ramsey. Weaning was performed using protocol-based pressure support trials. RESULTS: Total (SD) fentanyl dose during operation was 33 (6) microg x kg(-1) for propofol and 34 (6) microg x kg(-1) for oxycodone-thiopental (ns). The target sedation was achieved equally with both methods. The time from admission to intensive care unit to extubation was 494 (100) min for propofol and 521 (98) min for oxycodone-thiopental (ns). Weaning times were 63 (24) min and 112 (63) min in the propofol and oxycodone-thiopental groups, respectively (P<0.05). Breathing frequency increased and tidal volume decreased from weaning to 2 h postextubation. CONCLUSION: Propofol infusion and oxycodone-thiopental bolus dosages, titrated to the same sedation end point, resulted in similar time from admission to extubation, although the weaning period was shorter in the propofol group. In terms of breathing pattern, gas exchange, blood gases and haemodynamics, the methods were similar. Propofol, despite its attractive pharmacological profile, may offer no clinical benefit in short-term sedation after a moderate dose fentanyl anaesthesia in cardiac surgery.

Carbon Dioxide↗
PubMed2000

Assessment of the adequacy of systemic and regional perfusion after cardiac surgery.

Changes in systemic, hepatosplanchnic and femoral blood flow and liver function after cardiac surgery were studied in 17 patients from April to October 1995. Blood flows were measured every 3 h and gastric mucosal PCO2 (by tonometry) every hour from arrival in the intensive care unit until extubation. Cardiac output and systemic oxygen consumption increased from 2.83 (0.68) litres min-1 m-2 to 3.17 (0.57) litres min-1 m-2 and from 126 (18) ml min-1 m-2 to 135 (44) ml min-1 m-2, respectively (mean (SD), P = 0.028 and P = 0.019, respectively, baseline vs 6 h). The fraction of cardiac output distributed to the splanchnic region decreased from 0.25 (0.06) to 0.20 (0.04) (P = 0.004) while splanchnic oxygen extraction increased from 0.43 (0.15) to 0.50 (0.12) (P = 0.019). Femoral blood flow increased from 0.18 (0.07) litres min-1 m-2 to 0.23 (0.09) litres min-1 m-2, (P = 0.006, baseline vs 3 h) but femoral oxygen consumption did not change. Changes in blood flow were not reflected by venous-arterial PCO2 gradients. Initially high glutathione transferase alpha concentrations decreased and indocyanine green extraction was well preserved. We conclude that the predominant increase in peripheral blood flow and the increased oxygen uptake in certain regions of the body may increase the risk of a mismatch between splanchnic perfusion and metabolic demands. This mismatch was not associated with impaired liver function or cellular integrity.

Aged↗
PubMed2000

Repetitive synchronized cyclical oscillations of multisystem parameters subsequent to high-dose thiopental therapy for status epilepticus secondary to herpes encephalitis.

We report a case of status epilepticus secondary to herpes encephalitis, treated with thiopental infusion and mechanical ventilation. The computerized storage and analysis of physiological data led to the detection of repetitive synchronized cyclical oscillations of arterial pressure, heart rate, EEG parameters, peripheral temperature and core temperature. Arterial pressure oscillations have been described in patients who are severely systemically unwell; cardiovascular and brain electrical activity may also oscillate in the presence of raised intracranial pressure. In contrast, this patient had no features of severe systemic illness or of raised intracranial pressure. Our hypothesis is that high-dose thiopental may have been a cause of our findings by producing autonomic dysfunction.

Adolescent↗
PubMed2000

Gastric mucosal end-tidal PCO2 difference as a continuous indicator of splanchnic perfusion.

Gastric mucosal and arterial blood PCO2 must be known to assess mucosal perfusion by means of gastric tonometry. As end-tidal PCO2 (PE'CO2) is a function of arterial PCO2, the gradient between PE'CO2 and gastric mucosal PCO2 may reflect mucosal perfusion. We studied the agreement between two methods to monitor gut perfusion. We measured the difference between gastric mucosal PCO2 (air tonometry) and PE'CO2 (= DPCO2gas) and the difference between gastric mucosal PCO2 (saline tonometry) and arterial blood PCO2 (= DPCO2sal) in 20 patients with or without lung injury. DPCO2gas was greater than DPCO2sal but changes in DPCO2gas reflected changes in DPCO2sal. The bias between DPCO2gas and DPCO2sal was 0.85 kPa and precision 1.25 kPa. The disagreement between DPCO2gas and DPCO2sal increased with increasing dead space. We propose that the disagreement between the two methods studied may not be clinically important and that DPCO2gas may be a method for continuous estimation of splanchnic perfusion.

Carbon Dioxide↗
PubMed2000

A prospective, randomized study of goal-oriented hemodynamic therapy in cardiac surgical patients.

UNLABELLED: Organ dysfunction and multiple organ failure are the main causes of prolonged hospital stay after cardiac surgery, which increases resource use and health care costs. Increased levels of oxygen delivery and consumption are associated with improved outcome in different groups of postoperative patients. Cardiac surgical patients are at risk of inadequate perioperative oxygen delivery caused by extracorporeal circulation and limited cardiovascular reserves. The purpose of our study was to test whether increasing oxygen delivery immediately after cardiac surgery would shorten hospital and intensive care unit (ICU) stay. Four hundred three elective cardiac surgical patients were enrolled in the study and randomly assigned to either the control or the protocol group. Goals of the protocol group were to maintain SvO(2) >70% and lactate concentration < or =2.0 mmol/L from admission to the ICU and up to 8 h thereafter. Hemodynamics, oxygen transport data, and organ dysfunctions were recorded. The median hospital stay was shorter in the protocol group (6 vs 7 days, P < 0.05), and patients were discharged faster from the hospital than those in the control group (P < 0.05). Discharge from the ICU was similar between groups (P = 0. 8). Morbidity was less frequent at the time of hospital discharge in the protocol group (1.1% vs 6.1%, P < 0.01). Increasing oxygen delivery to achieve normal SvO(2) values and lactate concentration during the immediate postoperative period after cardiac surgery can shorten the length of hospital stay. IMPLICATIONS: Health care economics has challenged clinicians to reduce costs and improve resource use in cardiac surgery and anesthesia in a patient population increasing in age and in severity of disease. Optimizing cardiovascular function to maintain adequate oxygen delivery during the immediate postoperative period after cardiac surgery can decrease morbidity and reduce length of hospital stay.

Cardiac Surgical Procedures↗
PubMed2000

Effect of dopexamine on outcome after major abdominal surgery: a prospective, randomized, controlled multicenter study. European Multicenter Study Group on Dopexamine in Major Abdominal Surgery.

OBJECTIVE: To test the hypothesis that dopexamine reduces postoperative mortality and morbidity in high-risk, major abdominal surgery patients, when given to fluid-resuscitated patients starting before the operation and continued for 24 hrs after surgery. DESIGN: Prospective, randomized, controlled, double-blind multicenter trial. SETTING: Intensive care units in 13 hospitals from six European countries. PATIENTS: A total of 412 patients with predefined high-risk criteria, undergoing major abdominal surgery with an expected duration of at least 1.5 hrs. INTERVENTIONS: The patients received placebo (n = 140), dopexamine at 0.5 microg/kg/min (n = 135), or dopexamine at 2.0 microg/kg/ min (n = 137) starting after preoperative hemodynamic stabilization and continued for 24 hrs after surgery. MEASUREMENTS AND MAIN RESULTS: The primary outcome variable was mortality at 28 days. Analysis was by intention to treat. Dopexamine had no effect on mortality (at 28 days, 13%, 7%, and 15%, for the groups receiving placebo, dopexamine at 0.5 microg/kg/ min, and dopexamine at 2.0 microg/kg/min, respectively), despite the expected dose-dependent hemodynamic responses. No effect was observed on the occurrence of organ dysfunction, duration of intensive care unit stay, or length of hospital stay. CONCLUSION: We conclude that dopexamine in doses that result in increased cardiac output and oxygen delivery after preoperative stabilization with fluids does not improve outcome after major abdominal surgery compared with fluids alone. Based on post hoc subgroup analysis and stratification according to the number of risk factors, we suggest that the concept should be further tested in patients at higher risk of complications or undergoing emergency surgery.

Adrenergic beta-Agonists↗
PubMed2000

Effects of dobutamine on splanchnic tissue perfusion during partial superior mesenteric artery occlusion.

OBJECTIVE: To evaluate the effects of dobutamine and fluid treatment on splanchnic hemodynamics and tissue oxygenation during partial superior mesenteric artery occlusion. DESIGN: Prospective, open randomized, full-factorial design. SETTING: University research laboratory. SUBJECTS: Forty-eight female pigs. INTERVENTIONS: In 24 anesthetized pigs (ischemic group), superior mesenteric artery (SMA) blood flow was reduced to 30% from the baseline for 120 mins; 24 pigs (sham group) served as nonischemic controls. The animals were further assigned into four treatment arms. In the control arm, the animals were administered only basic fluid therapy. In the fluid therapy arm, pulmonary artery occlusion pressure was maintained at 10 mm Hg with fluids. In the dobutamine treatment arm, dobutamine hydrochloride was infused at a dose of 10 microg/min/kg. In the combined dobutamine-fluid therapy arm, dobutamine at 10 microg/min/kg was administered and pulmonary artery occlusion pressure was maintained at 10 mm Hg with fluids. MEASUREMENTS AND MAIN RESULTS: Systemic and regional hemodynamics and oxygen transport, as well as jejunal intramucosal pH, intramucosal-arterial PCO2 gradient, and portal venous-arterial lactate gradient were measured. Ischemia did not modify the effects of fluids or dobutamine on systemic hemodynamics and oxygen transport. Dobutamine-treated animals had a higher cardiac index compared with control animals (218 +/- 22 vs. 135 +/- 13 mL/min/kg; p = .012), and the effect was enhanced when dobutamine was combined with fluid treatment (365 +/- 23 mL/ min/kg; p = .019). Fluid treatment alone did not influence cardiac index, whereas it increased SMA blood flow compared with control groups (15 +/- 2 vs. 12 +/- 2 mL/min/kg; p = .023). Dobutamine also decreased the proportion of SMA blood flow of cardiac output compared with control groups (6 +/- 1 vs. 9% +/- 1%; p = .024). Other treatments had no effect on SMA blood flow. Ischemia increased intramucosal-arterial Pco2 gradient to 54.8 +/- 10.7 torr (7.31 +/- 1.43 kPa) (p = .002 vs. sham control) and decreased intramucosal pH to 7.13 +/- 0.06 (p = .028 vs. sham control). In the ischemic animals, dobutamine without fluid therapy reduced intramucosal pH further to 7.00 +/- 0.09 (p = .023 vs. ischemic control) and increased portal venous-arterial lactate gradient (p = .033). CONCLUSIONS: Dobutamine alone worsened splanchnic tissue perfusion during partial superior mesenteric artery occlusion. As compared with fluid treatment alone, the combination of fluid and dobutamine therapy did not improve tissue perfusion.

Animals↗
PubMed2000

Jejunal and gastric mucosal perfusion versus splanchnic blood flow and metabolism: an observational study on postcardiac surgical patients.

OBJECTIVES: To evaluate the association between changes in total splanchnic and mucosal perfusion, assessed either by gastric tonometry or jejunal laser Doppler flowmetry in postcardiac surgical patients. DESIGN: A prospective, observational study. SETTINGS: A general intensive care unit in a tertiary care center. PATIENTS: Twelve, postoperative cardiac surgery patients were studied. INTERVENTIONS: Patients were treated according to clinical routine. Total splanchnic blood flow (indocyanine green extraction), jejunal mucosal perfusion (laser Doppler flowmetry), gastric mucosal-arterial PCO2 gradients, and splanchnic lactate uptake were studied during four 30-min measurements periods, each separated by a period of 1 hr. MEASUREMENTS AND MAIN RESULTS: There was no consistent association between either total splanchnic and local mucosal perfusion or between gastric and jejunal perfusion as assessed by two different techniques. The PCO2 gradient increased from 0.73+/-0.21 kPa to 1.15+/-0.30 kPa (p < .05), and splanchnic oxygen extraction increased from 40%+/-9% to 49%+/-14% (p < .01). CONCLUSIONS: In this observational study on postcardiac surgical patients, local mucosal perfusion did not reflect total splanchnic blood flow and vice versa. Either changes in gastric and jejunal mucosal perfusion were different or increasing tissue metabolism was responsible for the observed lack of association between tonometry, laser Doppler flowmetry, and total splanchnic blood flow. Increasing mucosal arterial PCO2 gradient and splanchnic oxygen extraction may reflect a mismatch between splanchnic perfusion and metabolic demands.

Adult↗