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Biomedical subjects

A Kari

Publications and source records attributed to A Kari.

At least 37 records · Page 2Linked to original sources
PubMed1994

Information transfer in high dependency environments: an ergonomic analysis.

We have studied the information flow in HDE (with special focus on the information transfer process) using data provided by a group of experienced health care professionals. A model of the information flow in HDE was built up. It postulates the existence of quanta of information (due to the artificial fragmentation of the information flow produced by the clinical working processes: organization in shifts, demand of simultaneous activities from different staff members, etc.). This fragmentation is described by using the so-called Clinical Information Process Units (CIPUs), which correspond to patient care activities going on in parallely and serially linked blocks, performed by the staff in the specific environments. Due to a transfer in responsibility over the patient the CIPUs are linked by information transfer events which are described using transfer modules (TraMs). We exemplified 32 CIPUs related to the clinical environments (PreOp, Surgery, Recovery Intensive Care, Ward, Diagnostics, Outpatient) and the health care professional groups (Anesthesiologist/Intensivist, Surgeon, Nurse, Physician, Diagnostic Physician, Physical Therapist). A matrix was established providing the transfer situations among the CIPUs enabling a systematic classification of the TraMs. The contents of the TraMs are built up of information link elements, which are assembled according to the specific settings of the transfer situation given by the emitter, receiver and purpose. In summary we modelled the process of information transfer in HDE through CIPUs, TraMs and information links in a way, which may be useful to design information technology applications or to reorganize the information management in HDE.

Anesthesiology↗
PubMed1994

Contribution of non-neurologic disturbances in acute physiology to the prediction of intensive care outcome after head injury or non-traumatic intracranial haemorrhage.

OBJECTIVE: To study the additional contribution of non-neurologic disturbances in acute physiology and chronic health to the prediction of intensive care outcome in patients with head injury or non-traumatic intracranial haemorrhage. DESIGN: A nationwide study in Finland with prospectively collected data on all adult patients admitted to intensive care after head trauma or non-traumatic intracranial haemorrhage during a 14-month period. Two-thirds of the patients were randomly selected to derive predictive models, and the remaining one third constituted the validation sample. SETTING: A total of 25 medical and surgical ICUs in Finland (13 in tertiary referral centers). PATIENTS: 901 consecutive adult patients with head injury or non-traumatic intracranial haemorrhage. MEASUREMENTS AND RESULTS: Variables of the APACHE II including Glasgow Coma Score were collected at the time of ICU admission. Two predictive models were created to explain hospital mortality. The addition of variables describing acute physiology to a predictive model consisting of Glasgow Coma Score, age, diagnosis of head injury and the type of ICU admission did not increase its performance in discriminating between survivors and nonsurvivors, but the calibration accuracy of the predictive model especially at the high ranges of risk was improved. CONCLUSIONS: The non-neurologic disturbances in acute physiology have prognostic significance in the prediction of intensive care outcome in patients with head injury or non-traumatic intracerebral haemorrhage. The created predictive model may supplement clinical judgement of this patient group.

APACHE↗
PubMed1994

Prediction of outcome from intensive care after gastroenterologic emergency.

Prognostic factors determining the outcome from intensive care were studied in 952 patients admitted to 25 Finnish ICUs after gastroenterologic emergency. Logistic regression analysis was used to create predictive models based on the APACHE II-system. The models were constructed by using data from a random two-thirds of the study population and validated in the remaining independent one-third together with the original APACHE II-index. The Acute Physiology Score, age, and a pre-existing liver disease were the three most important determinants of outcome. The inclusion of the TISS score describing the intensity of treatment into a model did not enhance the accuracy of the prediction. Our models were better calibrated than the original APACHE II-equation when tested by the goodness-of-fit -statistics. These statistical models may help the clinicians to predict the outcome for an individual patient by providing them information about the relative impacts of predictive factors or about the probability of death. These probabilities should be interpreted cautiously, taking into account the limitations of statistical methods. This is especially important when assessing the highrisk patients. Their number in our study was too low for accurate outcome prediction.

APACHE↗
PubMed1993

The effect of antenatal dexamethasone administration on the fetal and neonatal ductus arteriosus. A randomized double-blind study.

OBJECTIVE: To determine whether antenatal dexamethasone sodium phosphate administration constricts the fetal ductus arteriosus or improves spontaneous closure of the ductus in premature infants. DESIGN: A randomized double-blind study. SETTING: University hospital of Helsinki, Finland. PARTICIPANTS: Sixty-one pregnant women with threatened preterm delivery between 24 and 31.9 weeks' gestation and 57 of their offspring (28 in the dexamethasone and 29 in the placebo group), born at 24 to 34.9 weeks' gestation, were studied using Doppler echocardiography. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Between the dexamethasone and placebo groups, there were no significant differences in systolic or diastolic flow velocity values in the fetal ductus arteriosus. Of the 29 infants with respiratory distress syndrome, 26 (90%) had hemodynamically significant patent ductus arteriosus and received indomethacin sodium: 12 (92%) of 13 dexamethasone-treated infants and 14 (88%) of 16 placebo-treated infants. One placebo-treated infant was ligated. Of the 28 infants without respiratory distress syndrome, only four (14%) had hemodynamically significant patent ductus arteriosus. In infants born at or before 30 weeks' gestation, spontaneous closure of the ductus occurred more frequently after administration of prenatal dexamethasone (in six of 17 infants; 35%) than placebo (in none of 10 infants; P < .05). CONCLUSIONS: Our data indicate that antenatal dexamethasone administration had no constrictive effect on the ductus arteriosus of the fetus between 24 and 31 weeks' gestation. However, antenatal dexamethasone had a beneficial effect on ductal closure in very premature infants.

Adult↗
PubMed1993

A knowledge-based alarm system for monitoring cardiac operated patients--technical construction and evaluation.

A knowledge-based alarm system for intensive care monitoring was designed, built, tested on-line, and evaluated. The system is a functional prototype of a highly specific patient monitor providing alarms on hypovolemia, hyperdynamic state, left ventricular failure and hypoventilation. These intelligent alarm functions aim to maintain the quality of patient monitoring even if nurses' attention is temporarily reduced or focused elsewhere. The alarm system has an electronic access to data available in a multichannel patient monitor and the patient data management system of the intensive care unit. Median filtering, trend estimation, and rule-based reasoning are applied when processing the measured variables and estimating the patient's state.

Artificial Intelligence↗
PubMed1993

Shunt-dependent hydrocephalus after subarachnoid haemorrhage and aneurysm surgery: timing of surgery is not a risk factor.

Early hydrocephalus is a risk factor of shunt-dependent late hydrocephalus (SDHC). In the CT era 1980-1990 we had 835 consecutive patients operated on because of aneurysm and subarachnoid haemorrhage (SAH); 294 had an early hydrocephalus and 67 finally required a shunt. There were 14 patients with normal early CT and SDHC, in all 81 patients needed a shunt (10%). Patients with shunt did worse, they were older (53 vs 49) than the non-shunted group and there was a female preponderance. Pre-operative Grade correlated significantly with the need for a shunt operation; no one in Grade I developed SDHC, incidence in Grades III and IV was high (18% and 10%, respectively). Location was important; in vertebrobasilar area 28% and in anterior communicating area 14% but in middle cerebral area only 4% of the patients had SDHC. The amount of cisternal bleeding correlated significantly with SDHC; in 155 patients with non detectable or minimal cisternal blood only one developed SDHC, with severe cisternal bleeding the incidence was 16%. Ventricular bleeding increased the risk of SDHC, but intracerebral haematoma did not. Timing of surgery had no correlation with the risk of SDHC. Postoperative complications, haematomas and infections increased the risk of late SDHC. Delayed ischaemia correlated with the risk, but so did the treatment with nimodipine. Severe bleeding was the common predictor for the risk of SDHC. Location of the bleeding and postoperative problems are the other major causes. Outcome is, however, not so gloomy; 54% of patients with SDHC are independent one year later.

Adult↗
PubMed1993

One-year outcome in early aneurysm surgery: a 14 years experience.

In a consecutive series of 1150 patients with cerebral aneurysms diagnosed in our department by angiography or autopsy between the years 1977-1990, 1007 patients underwent definitive operative treatment of their aneurysms mainly by early surgery. More than half (55%) were operated on during the first three days after subarachnoid haemorrhage (SAH), and more than three quarters (77%) during the first week. The surgical mortality at 30 days was 9%; at one-year follow-up 13% had died. The total management mortality was 22%. The 618 patients presenting in Hunt and Hess Grades I-II had a 4% mortality, and 90% had an independent life at follow-up; 270 Grade III patients had a 19% mortality and 68% were independent. There were 99 patients operated on in Grades IV-V with a 46% mortality and 30% were independent. Age of the patient and size of the aneurysm were strongly related to outcome; however, many of the giant aneurysms were operated on as an emergency because of large intracerebral haematomas. Best results were obtained in the anterior communicating artery (ACA) area; the lowest rate of useful recoveries was in the vertebro-basilar artery (VBA) area (71%). Early surgery did not prevent delayed ischaemic deficits. During the first 72 hours patients in Grades I-III can be operated on safely with good results. The results in Grades IV-V are poor, and we suggest that only cases with large haematomas or considerable hydrocephalus or those improving should be operated on in the first days after SAH, with limited hopes of functional recovery.

Adolescent↗
PubMed1993

One-year outcome in early aneurysm surgery: prediction of outcome.

Predictors of one-year outcome were studied in patients treated for ruptured intracranial aneurysm. A total of 929 patients, who were treated conservatively or surgically, and 839 patients as a part of this population who were surgically treated, were randomly divided into two groups in order to create predictive models by logistic regression and to validate them. The models were derived from two-thirds of these two patient groups and the remaining one-thirds were used for validation. The pre-operative variables of both conservatively and surgically treated patients were studied by Model A. The pre-operative Grade (Hunt and Hess), age, and the presence of vasospasm on angiography were the three most important predictors of the one-year outcome (Glasgow Outcome Scale 1-2/3-5). Model B consisted of pre- and per-operative, and Model C pre-, per-, and post-operative variables collected from the surgically treated group. The pre-operative Grade, ligation of a major vessel and age were the three most powerful determinants of outcome in Model B. In Model C high Grade, post-operative CT-hypodensities and ligation of a major vessel were most closely associated with poor outcome. Model A, based on pre-operative data, most accurately predicted good outcome. All the 59 patients in the validation sample (n = 310) who were predicted to have a less than 5% probability of poor outcome had a favourable outcome (positive and negative predictive value 100%). Model C determined that 22 of 280 patients would have a more than 80% probability of poor outcome.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1993

Urinary excretion of polyamines in patients with surgical and accidental trauma: effect of total parenteral nutrition.

Excretion of polyamines first increases and then decreases in patients with multiple trauma receiving total parenteral nutrition (TPN). To separate the effects of trauma and TPN on polyamine excretion, we studied 12 patients with multiple trauma and 14 patients after surgery for colorectal malignancy. Patients were randomized to receive either TPN or hypocaloric glucose infusion. Urinary excretion of total and free polyamines, putrescine (PU), spermidine (SPD), and spermine (SP), and their metabolites, N1-acetylspermidine (N1-AcSPD) and N8-acetylspermidine (N8-AcSPD), and energy and nitrogen balance were measured. Polyamine excretion, excluding SP, markedly increased after trauma and surgery, exceeding the normal values by twofold to 10-fold. In patients receiving TPN, the excretion of total polyamines was 48% higher (P < .01), PU was 34% higher (P < .05), SPD was 35% higher (P < .05), and SP was 350% higher (P < .05) than in patients receiving hypocaloric glucose. Urinary excretion of SP was only 17% of the reference value during hypocaloric glucose (P < .05), but was normal during TPN. The difference in polyamine excretion between nutrition groups was more pronounced when normalized for nitrogen or energy balance. Patients receiving TPN were more hypermetabolic than patients receiving hypocaloric glucose (resting energy expenditure, 1.36 +/- 0.06 [SE] and 1.16 +/- 0.04 times predicted values, respectively; P < .025). Statistically, energy expenditure could explain the difference in polyamine excretion between nutrition groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Regional blood flow and oxygen transport in septic shock.

OBJECTIVE: To measure the blood flow distribution and regional oxygen transport in hyperdynamic septic shock during hypotension and after correction by vasopressor doses of dopamine or norepinephrine. DESIGN: Prospective, randomized, controlled trial. SETTING: Tertiary care center. PATIENTS: Ten patients with hyperdynamic septic shock (ages ranging from 45.1 +/- 16.6 yrs) and a control group of 11 postoperative cardiac surgery patients (ages ranging from 54.8 +/- 7.9 yrs). INTERVENTIONS: Systemic and regional hemodynamics and oxygen transport were measured in ten patients with hyperdynamic septic shock during hypotension and after vasopressor therapy (norepinephrine or dopamine). Oxygen consumption (VO2) was measured by indirect calorimetry and splanchnic and leg blood flow with indocyanine green infusion. MEASUREMENTS AND MAIN RESULTS: Splanchnic blood flow and VO2 (p < .05) were increased in septic shock during hypotension and during vasopressor therapy. Both dopamine and norepinephrine increased systemic blood flow and VO2 independently of the arterial lactate level. Despite the relatively small changes in systemic oxygen transport, major regional changes occurred in oxygen delivery and VO2, and these changes were unpredictable from systemic changes. CONCLUSIONS: Regional changes in oxygen transport in septic shock cannot be predicted from the changes in the whole body. The increased oxygen demand in the splanchnic region is the main risk factor for splanchnic tissue hypoxia in septic shock.

Adolescent↗
PubMed1993

Regional blood flow and oxygen transport in patients with the low cardiac output syndrome after cardiac surgery.

OBJECTIVE: To assess systemic and regional oxygen transport after open heart surgery in patients with the low cardiac output syndrome who are receiving vasoactive drugs and in patients with normal hemodynamics during spontaneous rewarming. DESIGN: Prospective, nonrandomized controlled trial. SETTING: Tertiary care center. PATIENTS: Sixteen patients aged 53.1 +/- 8.4 yrs were studied after coronary artery bypass operations: ten patients with a cardiac index of < 1.75 L/min/m2 and six control patients with a cardiac index of > 1.75 L/min/m2. INTERVENTIONS: The patients with a cardiac index of < 1.75 L/min/m2 received either dobutamine alone (n = 5) or in combination with nitroprusside (n = 5). The control patients with a cardiac index of > 1.75 L/min/m2 did not receive vasoactive treatment. The systemic oxygen consumption was measured by indirect calorimetry and the regional blood flow was measured by primed continuous infusion of indocyanine green. MEASUREMENTS AND MAIN RESULTS: Both splanchnic and femoral blood flows increased (p < .05) in parallel with cardiac output during vasoactive drug therapy. High splanchnic oxygen extraction in patients with low cardiac index and flow-dependent splanchnic oxygen consumption in some patients indicated marginal splanchnic oxygen delivery. In addition, femoral blood flow was low and oxygen consumption changed in parallel with oxygen delivery in patients with the low cardiac output syndrome. CONCLUSIONS: In low cardiac output syndrome after cardiac surgery, splanchnic oxygen delivery was marginal and was maintained at the expense of peripheral oxygen delivery. Dobutamine, both alone and in combination with sodium nitroprusside, improved splanchnic oxygen delivery.

Body Temperature↗
PubMed1993

Value of absent or retrograde end-diastolic flow in fetal aorta and umbilical artery as a predictor of perinatal outcome in pregnancy-induced hypertension.

There is insufficient data on the value of absent or retrograde end-diastolic flow (AREDF) in the fetal umbilical artery, descending aorta and aortic arch to predict perinatal outcome. In this prospective investigation, 65 pregnant women between 24 and 34 weeks' gestation with pregnancy-induced hypertension were studied by color Doppler echocardiography. Pregnancies leading to birth at or before 34.0 gestational weeks (23 with and 19 without AREDF) were included in the outcome analysis. Fetuses with AREDF were delivered at earlier gestational ages (p = 0.006). They had a higher incidence of gastrointestinal complications (p = 0.01), bronchopulmonary dysplasia (p = 0.03), intraventricular hemorrhage (p = 0.03) and vascular hypotension (p = 0.03) than those without AREDF. The presence of AREDF was associated with a mortality rate of 30%, whereas in fetuses without AREDF there was no mortality (p = 0.01). Using logistic regression and taking into consideration various perinatal factors, the presence of AREDF (p = 0.03) and early gestational age (p = 0.0001) were associated with serious neonatal diseases or death. A reverse diastolic flow in the aortic isthmus was registered in five fetuses; three died during the perinatal period and one was severely damaged. According to our results, AREDF, particularly with the appearance of reverse diastolic flow in the isthmus of the aortic arch, is a predictor of poor neonatal outcome.

Adult↗
PubMed1993

Increased urinary polyamine excretion after starting a very low calorie diet.

Urinary polyamine excretion has been suggested to reflect hypermetabolism or catabolism in different illnesses. In the present study, the excretion of urinary polyamines was examined in 12 obese subjects (3 men, 9 women aged 32-55 y, body mass index 33.3-64.7 kg m-2) before and during a very low calorie diet (the total calorie intake 2100-3350 kJ). In addition, nitrogen balance, basal energy expenditure (BEE) and serum thyroid hormone levels were examined. During the first week on a very low calorie diet (VLCD) the mean body weight declined from 121.8 +/- 27.3 to 117.4 +/- 26.2 kg (mean +/- SD, p < 0.001), and after 12 weeks of treatment body weight was 106.6 +/- 24.6 kg. Immediate reduction of BEE from 1.44 +/- 0.24 to 1.34 +/- 0.24 kcal min-1 (p < 0.001) was found within the first week of therapy and BEE measured on weight-maintaining diet remained lower at 12 weeks (1.25 +/- 0.27 kcal min-1, p < 0.01). Serum free T3 decreased and reverse T3 increased significantly after starting VLCD. Nitrogen balance remained negative during the first 2 weeks on VLCD. A significant increase in total (38%), and in N1-acetyl- and N8-acetylspermidine excretions in the urine (40% and 27%, respectively, p < 0.05) was found during the first week, but later on the levels were not significantly different from the baseline levels.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1992

INFORM: European survey of computers in intensive care units.

The aims of this study were (a) to survey and evaluate the impact of information technology applications in High Dependency Environments (HDEs) on organizational, psychological and cost-effectiveness factors, (b) to contribute information and design requirements to the other workpackages in the INFORM Project, and (c) to develop useful evaluation methodologies. The evaluation methodologies used were: questionnaires, case studies, objective findings (keystroke) and literature search and review. Six questionnaires were devised covering organizational impact, cost-benefit impact and perceived advantages and disadvantages of computerized systems in HDE (psychological impact). The general conclusion was that while existing systems have been generally well received, they are not yet designed in such a developed and integrated way as to yield their full potential. Greater user involvement in design and implementation and more emphasis on training emerged as strong requirements. Lack of reliability leading to parallel charting was a major problem with the existing systems. It proved difficult to assess cost effectiveness due to a lack of detailed accounting costs; however, it appeared that in the short term, computerisation in HDEs tended to increase costs. It is felt that through a better stock control and better decision making, costs may be reduced in the longer run and effectiveness increased; more detailed longitudinal studies appear to be needed on this subject.

Case-Control Studies↗
PubMed1992

Continuous measurement of cardiac output by the Fick principle: clinical validation in intensive care.

OBJECTIVE: To compare continuous measurement of cardiac output by the Fick principle with the thermodilution cardiac output technique in hemodynamically unstable patients. DESIGN: An open comparison of two methods. SETTING: Multidisciplinary ICU in a university hospital. PATIENTS: Eight patients after coronary bypass surgery and 13 patients with hyperdynamic septic shock. All patients were mechanically ventilated. MEASUREMENTS AND MAIN RESULTS: The continuous Fick cardiac output technique was compared with the thermodilution cardiac output using both warm and cold injection in the coronary artery bypass surgery patients and using warm injection only in the patients with hyperdynamic septic shock. The mean difference between the continuous cardiac output technique and all thermodilution measurements (n = 201) was 0.6 +/- 19%. There was a good correlation between the continuous cardiac output and the warm thermodilution technique (n = 125, r2 = .79; p less than .001). When consecutive measurements with warm and cold thermodilution were compared with the respective Fick-derived values (n = 76), the mean differences between the Fick-derived and the warm and cold thermodilution cardiac output values were 0.2 +/- 1.0 L/min and 0.3 +/- 1.0 L/min, respectively. The relationship between Fick-derived and both methods of thermodilution-derived cardiac output was relatively constant during different modes of ventilatory support. The correlation between the thermodilution measurements with cold and room temperature injectate was weak (r2 = .36; p less than .001), whereas a good correlation was observed between the respective Fick-derived values (r2 = .73; p less than .001). The mean difference between the warm and cold thermodilution cardiac output measurements was 0.1 +/- 1.1 L/min and between the corresponding Fick-derived measurements was 0.01 +/- 0.7 L/min. CONCLUSIONS: Continuous measurement of cardiac output by the Fick principle offers a convenient, reproducible method for hemodynamic monitoring of unstable patients. The variation between the two tested thermodilution techniques is likely to reflect relatively rapid dynamic variation of cardiac output, which is filtered in the 1-min average of cardiac output obtained by the continuous Fick technique.

Adult↗
PubMed1992

Does the anesthetic method influence the postoperative breathing pattern and gas exchange in hip surgery? A comparison between general and spinal anesthesia.

We studied the effects of elective hip surgery, performed under either spinal (SA, n = 10) or general anesthesia (GA, n = 10), on breathing pattern and gas exchange. Measurements were made with respiratory inductive plethysmograph and indirect calorimetry in two positions before and after surgery. The method of anesthesia had no effect on the severity of postoperative hypoxemia. Reduced arterial oxygenation (PaO2; P less than 0.001, SA from 12.5 +/- 2.37 kPa to 10.5 +/- 1.38 kPa, GA from 12.5 +/- 2.95 kPa to 10.5 +/- 1.75 kPa) despite increased alveolar ventilation (P less than 0.01; from 2.30 +/- 0.37 l/min to 2.39 +/- 0.43 l/min in SA, 2.27 +/- 0.56 l/min to 2.57 +/- 0.35 l/min in GA) and reduced arterial carbon dioxide partial pressure (PaCO2; SA from 5.20 +/- 0.22 kPa to 4.95 +/- 0.33 kPa, P less than 0.01, GA from 5.07 +/- 0.36 kPa to 4.72 +/- 0.41 kPa, P less than 0.05) indicated maldistribution of ventilation and perfusion. Changes in breathing pattern and gas exchange and differences between the groups were minimal. Minute ventilation, tidal volume and mean inspiratory flow remained unchanged in both groups. The contribution of rib cage to tidal volume increased postoperatively in the supine position (P less than 0.001; SA from 32.6% +/- 10.3 to 46.3% +/- 7.5, GA from 36.5 +/- 16.4 to 48.5% +/- 15.4). CO2 production, oxygen consumption and energy expenditure remained unchanged. The postoperative changes in breathing pattern are related to the operation, not to the type of anesthesia and do not explain the alterations in gas exchange.

Adult↗