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J Takala

Publications and source records attributed to J Takala.

At least 109 records · Page 6Linked to original sources
PubMed1997

Calculated versus measured oxygen consumption during and after cardiac surgery. Is it possible to estimate lung oxygen consumption?

BACKGROUND: Lung tissue is metabolically active and consumes oxygen. The oxygen content difference between arterial and mixed venous blood does not include the effect of pulmonary tissue oxygen uptake. Thus, oxygen consumption (VO2) of the lung should be reflected as a difference between VO2 measured by gas exchange and VO2 derived by the Fick principle. The purpose of this study was to measure in clinical conditions this difference (taken to represent the VO2 of the lung), and to evaluate the sources of error in lung VO2 estimation. METHODS: Nine patients undergoing coronary artery bypass grafting were studied. VO2 was measured by indirect calorimetry (VO2gasex) and compared to Fick-derived VO2 (VO2Fick) after induction of anaesthesia, after closure of the chest, at admission to intensive care, after stabilization of haemodynamics and during weaning from mechanical ventilation. The Fick-derived VO2 was calculated from blood samples taken at the beginning and at the end of each 20 min measurement period, and the mean of 12 consecutive thermodilution cardiac output measurements taken during each 20 min measurement period. RESULTS: VO2gasex was higher than VO2Fick (P < 0.01; in all except 4 of 45 measurements). The difference between the measured and the calculated VO2 was 33 +/- 25 ml/min (mean +/- SD, range -16-100 ml/min). This difference represented 14 +/- 3% (range 11-18%) of the whole body VO2. The VO2-difference was highest after the induction of anaesthesia (50 +/- 19 ml/min; range 20-41 ml/min, P < 0.03) and lowest on arrival at the intensive care unit (10 +/- 16 ml/min; range -16-39 ml/min). Core temperature did not correlate with the oxygen consumption difference. CONCLUSIONS: A constant difference between measured and calculated VO2 can be detected in carefully controlled clinical conditions. The difference between the two methods is due to both lung oxygen consumption and errors in the measurement of VO2 thermodilution cardiac output, haemoglobin and blood oxygen contents. We suggest that the perioperative changes of the VO2-difference are due not only to variation of the measurements but also to changes in lung metabolic activity.

Adult↗
PubMed1997

Relationship between intra- and postoperative oxygen transport and prolonged intensive care after cardiac surgery: a prospective study.

BACKGROUND: Prolonged intensive care is a rare but serious complication of cardiac surgery. It is required in less than 10% of operated patients but they use more than 30% of all the intensive care resources needed for cardiac surgery. The aim of our study was to describe the clinical course of the patients who need prolonged intensive care following cardiac surgery and to assess whether the intra- and postoperative oxygen transport variables are different in these patients as compared to patients with an uncomplicated course. METHODS: The study patients were divided into two groups according to the length of stay in the intensive care unit (ICU) after the operation: Group I, n = 241, ICU-stay < 5 days and Group II, n 20, ICU-stay > or = 5 days. Hemodynamic and oxygen transport data were prospectively obtained intra- and postoperatively and postoperative organ dysfunctions were recorded. RESULTS: The patients in the prolonged intensive care group tended to be older, have lower ejection fraction and longer cardiopulmonary bypass time. Postoperatively, this group had significantly increased oxygen extraction rate (P = 0.035, repeated measures for ANOVA). In the logistic regression analysis, increased oxygen extraction (31% in Group I vs. 36% in Group II, P < 0.005) at 6 hours after arrival at the intensive care unit had the strongest independent association with the need for prolonged intensive care. CONCLUSIONS: There was no significant relationship between the factors conventionally assumed to be risk factors for prolonged intensive care. Instead, an increase in whole body oxygen extraction, reflecting a mismatch between the whole body oxygen demand and supply, was associated with the need for prolonged intensive care. Oxygen extraction increased to compensate for the reduced oxygen delivery, which in turn was caused by a lower arterial oxygen content.

Adult↗
PubMed1997

The list system can reduce the waiting time and number of consultations in a centralized primary care centre that provides out of hours medical care.

OBJECTIVE: To study the waiting time and number of consultations of the patients who required out of hours medical care from a centralized primary care centre before and after the introduction of a list system. DESIGN: Non-controlled intervention study. A questionnaire, completed by receptionists, concerning all out of hours general practice consultations for one week each month during two separate years (in 1990 with no list system and in 1993 with list system in operation). SETTING: One health centre in central Finland in a region with 39495 inhabitants. SUBJECTS: All patients contacting the health centre to request medical help during out of hours work. OUTCOME MEASURES: Consultation rates by age and sex of the patients and their waiting time before seeing the GP. RESULTS: In 1990, the average out of hours consultation rate per 1000 inhabitants per year was 826 for women and 819 for men. These figures were reduced by 271 for women (95% CI 262-280) and 305 for men (95% CI 297-314) in 1993. The mean waiting time was 55 min in 1990 and 32 min in 1993 (p < 0.001). CONCLUSION: The introduction of a list system leads to more effective primary care services.

Adolescent↗
PubMed1997

Effects of lisinopril or lisinopril/hydrochlorothiazide compared with adjusting of previous medication and intensifying non-pharmacological treatment in patients with mild to moderate hypertension.

The objective of this study was to compare the effectiveness of three treatment methods available for treatment of previously medicated patients with mild to moderate hypertension. The comparison was made between adjusting or increasing previous medication and switching the previous drug treatment to lisinopril (CAS 76547-98-3) or lisinopril hydrochlorothiazide (CAS 58-93-5) therapy and in both of these treatment groups the effect of additional intensified health education was tested. An open, randomised, controlled multi-centre study lasting 36 weeks involving 189 doctors and 69 nurses was carried out in 155 centres of primary health care and occupational health care system in Finland. The study population consisted of 1156 patients, age 30-70 years, (mean DBP 95-115 mmHg in the last three to five measurements during follow-up). The number of patients achieving target pressure (DBP < 90 mmHg) at the end of the study, defined daily doses (DDD) of antihypertensive drugs and side-effects in different treatment groups were regarded as the main outcome measures of the study. After exclusions and drop-outs the final analysis was carried out with 900 patients, 419 women (46.6%) and 481 men (53.4%). Patients receiving lisinopril treatment achieved target pressure significantly more often (p < 0.001) than those continuing their previous or adjusted medication at 36 weeks (59.2 and 55.5% vs 40.3 and 42.7%). Only a small additional but statistically non-significant blood pressure lowering effect was achieved with intensified non-pharmacological treatment at weeks 12 and 24, but this difference had disappeared at week 36. The mean DDDs of different antihypertensive drugs did not differ between groups except for female patients on previous or adjusted medication not receiving health education, the mean DDD being significantly (p < 0.05) higher at weeks 24 and 36 in this group. The profile of adverse effects at the end of the study clearly favoured patients on lisinopril treatment except for cough which was reported in 18% of patients vs 10% in the control groups. 81 patients on lisinopril treatment were withdrawn from the study because of cough. The results showed that hypertensive patients with poor treatment control benefit from all three approaches. A greater proportion of patients on lisinopril treatment achieved target pressure and also experienced fewer side effects than those continuing on adjusted previous medication. Intensified personal health education given once a month during six months had only a small additional beneficial effect on reaching the target pressure and this effect was lost in three months after the health education period.

Adult↗
PubMed1997

Treatment situation of hypertensive patients in Finnish primary health care.

OBJECTIVE: To highlight the present situation in hypertension control in Finnish primary healthcare. SUBJECTS AND METHODS: All health centre doctors from 30 primary health centres were asked to record every consulting patient, pick up hypertensives and evaluate their blood pressure (BP) level, drug treatment, side effects and symptoms related to drug treatment, and compliance during 2 weeks in May 1995. RESULTS: In all, 337 doctors from the 30 health centres participated in the study. They recorded altogether 4405 hypertensive patients, of which 1209 men (83%) and 2311 women (87%) had drug treatment for hypertension. Of all the drug-treated hypertensive men and women, 33% and 37%, respectively were obese (BMI > or = 30.0 kg/m2). Altogether, 13% of the drug-treated hypertensive men and 10% of women were in good control when BP < 140/90 mmHg was used as the criterion. These proportions doubled when BP < 160/90 mmHg and tripled when BP < 160/95 mmHg were applied as criteria. CONCLUSION: The proportion of drug-treated hypertensives under poor control is still high in Finland. Only a quarter of treated hypertensive patients are in good control when the criterion BP < 160/90 mmHg is applied.

Adult↗
PubMed1997

Venoarterial CO2 gradient after cardiac surgery: relation to systemic and regional perfusion and oxygen transport.

The difference in CO2 tension between venous and arterial blood (delta PCO2) increases in low-flow states. Therefore, delta PCO2 has been suggested as an additional variable in the monitoring of perfusion. We measured CO2 tensions in arterial, mixed venous, hepatic venous, and femoral venous blood in 42 postoperative cardiac surgery patients. Splanchnic and leg blood flow was measured with dye dilution. Forty-three preoperative abdominal surgery patients served as controls. Systemic and femoral delta PCO2 was increased in cardiac patients, whereas there was no difference in splanchnic delta PCO2 between the groups. In cardiac patients, systemic delta PCO2 correlated well with both splanchnic and femoral delta PCO2 (r2 = .74 and r2 = .56, respectively). Femoral delta PCO2 was higher than splanchnic delta PCO2 (1.27 +/- .44 kPa versus .66 +/- .41; p < .001) after cardiac surgery, but not in the control group. The correlation between delta PCO2 and respective blood flow was weak in the whole body, the splanchnic region, and the leg. When splanchnic blood flow was low, systemic and splanchnic delta PCO2 varied widely. In the cardiac patients with an increased systemic delta PCO2 (> .93 kPa), systemic and regional blood flow was low, but there were no differences in systemic or regional oxygen consumption or lactate levels. After cardiac surgery, high systemic delta PCO2 is associated with marginal systemic and regional perfusion. The adequacy of regional blood flow cannot be assessed on the basis of the systemic delta PCO2.

Arteries↗
PubMed1997

Patients with neck and shoulder complaints and multisite musculoskeletal symptoms--a prospective study.

OBJECTIVE: To examine reasons for and extent of health services utilization in patients seeking care for neck and shoulder pain in a population based primary care setting. METHODS: Patients seeking care for neck and shoulder pain were identified from medical records of 6526 patients visiting 6 primary care centers during a 2 week period. The extent of and reasons for health care utilization over the subsequent 12 month period were examined. RESULTS: Of 440 patients who consulted primary health care physicians for neck and shoulder pain, one-half had one or more additional episodes of care due to musculoskeletal (MSK) pain over the subsequent 12 months. One-quarter had additional episodes of care for pain in other sites than in the neck and shoulder. The total number of visits was twice the annual average for patients visiting the health centers, MSK symptoms accounting for half the visits. Twenty percent of the women and 7% of the men visited primary care physicians 10 times or more per year. CONCLUSION: The pattern of reasons for visits for MSK pain suggests that in about one-quarter of patients visiting primary care physicians for neck and shoulder pain, the local symptomatology is part of multisite MSK symptoms, resulting in frequent utilization of health services.

Adolescent↗
PubMed1996

Effect of nasogastric suction and ranitidine on the calculated gastric intramucosal pH.

OBJECTIVE: To study the effect of nasogastric suction and ranitidine on the determination of gastric intramucosal pH (pHi). DESIGN: Prospective study. SETTING: Clinical research unit at a university hospital intensive care department. SUBJECTS: 12 healthy volunteers. INTERVENTIONS: After a 2-h measurement control period a tonometer was connected to nasogastric suction for 2 h, and thereafter ranitidine was given intravenously and gastric pHi measured. MEASUREMENTS AND RESULTS: During each 2-h measurement period gastric PCO2, gastric pHi, and pH gap were determined every 30 min. Luminal pH was measured after insertion of tonometer and at the end of each study period. Neither nasogastric suction nor ranitidine had an effect on the coefficient of variation for either gastric PCO2 or pHi. Compared to control and nasogastric suction periods, after ranitidine mean gastric pHi was higher (control 7.22 +/- 0.08; nasogastric suction 7.23 +/- 0.07; after ranitidine 7.31 +/- 0.06, p < 0.001) mean gastric PCO2 lower (control 6.4 +/- 1.3; nasogastric suction 6.5 +/- 1.3; after ranitidine 5.3 +/- 0.9, p < 0.001) and pH gap lower (control 0.18 +/- 0.08; nasogastric suction 0.17 +/- 0.05; after ranitidine 0.09 +/- 0.06, p < 0.01). Luminal pH increased after ranitidine in each subject. CONCLUSIONS: H2 blockers have no effect on the reproducibility of gastric pHi measurements, but the use of H2 blockers modifies the normal values for gastric pHi in healthy subjects.

Adult↗
PubMed1996

Physiological effects of reduced tidal volume at constant minute ventilation and inspiratory flow rate in acute respiratory distress syndrome.

OBJECTIVE: To assess the effect of changes in tidal volume (VT) with a constant inspiratory flow and minute ventilation (VE) on gas exchange and oxygen transport in acute respiratory distress syndrome (ARDS). DESIGN: A crossover study of three VT in two study groups, using patients as their own controls. SETTING: A medical-surgical intensive care unit in a tertiary care center. PATIENTS: Eight patients with ARDS and seven postoperative cardiac surgery patients with uncomplicated recoveries were studied during volume-controlled mechanical ventilation. INTERVENTIONS: During controlled mechanical ventilation, patients were first ventilated with a VT of 9-11 ml/kg. VT was then increased to 12-14 ml/kg (+ 25%) for 30 min and subsequently decreased to 6-8 ml/kg (- 25%) for 30 min by adjusting the respiratory rate (RR) while the inspiratory flow rate, VE, and inspiratory duty cycle (TL/T(TOT)) were kept constant. At the end, patients were ventilated with the baseline settings for another 30 min. MEASUREMENTS AND RESULTS: VE, carbon dioxide production (VCO2) and oxygen consumption (VO2) were measured continuously with a gas exchange monitor, and cardiac output and arterial and mixed venous blood samples were taken at the end of each 30-min period to assess CO2 removal and oxygen transport. Alveolar minute ventilation (VA) and the deadspace to tidal volume ratio (VD/VT) were calculated from the Bohr equation. Despite large changes in VT, arterial oxygenation (PaO2) and oxygen transport (DO2) were unchanged throughout the study. When VT was increased, physiological VD increased from 448 +/- 34 ml to 559 +/- 46 ml (mean +/- SE) in ARDS (P < 0.001) and from 281 +/- 22 ml to 357 +/- 35 ml in CABG (P < 0.05). With the small VT, VD decreased to 357 +/- 22 ml in ARDS (P < 0.01), and to 234 +/- 24 ml in CABG (P < 0.05). In ARDS, VD/VT decreased from 0.57 +/- 0.03 to 0.55 +/- 0.03 (P < 0.05) with the large VT, and increased to 0.60 +/- 0.03 (P < 0.01), when VT was reduced. In CABG, VD/VT did not change significantly. ARDS patients had a higher PaCO2 than cardiac patients (P < 0.001), and only minor changes in PaCO2 were observed (for ARDS and CABG respectively, baseline 5.9 +/- 0.3 kPa and 4.1 +/- 0.1 kPa, large VT 5.7 +/- 0.3 kPa and 4.1 +/- 0.2 kPa, small VT 6.2 +/- 0.3 kPa and 4.2 +/- 0.2 kPa; P < 0.05). CONCLUSIONS: Tidal volumes can be reduced to 6-8 ml/kg in ARDS patients without compromising oxygen transport, while adequate CO2 elimination can be maintained.

Adult↗
PubMed1996

Splanchnic oxygen transport after cardiac surgery: evidence for inadequate tissue perfusion after stabilization of hemodynamics.

OBJECTIVE: To evaluate the adequacy of visceral oxygen transport and gastric pHi after open heart surgery in patients with stable hemodynamics. DESIGN: Nonrandomized control trial. SETTING: A general intensive care unit in a tertiary care center. PATIENTS: Sixteen postoperative cardiac surgery patients were studied after stabilization of systemic hemodynamics. INTERVENTIONS: The effect of dobutamine infusion (6 mu g kg-1 min-1) on systemic and regional oxygen transport was studied in ten patients, with six patients serving as controls. Systemic oxygen consumption was measured by indirect calorimetry and splanchnic and femoral blood flow, by continuous infusion of indocyanine green using regional catheters and gastric mucosal pHi by gastric tonometer. MEASUREMENTS AND RESULTS: Gastric mucosal acidosis was observed in half of the patients. Dobutamine increased cardiac output (3.2 +/- 0.6 vs 4.4 +/- 0.7 l x min-1 x min-2; P <0.05), splanchnic blood flow (0.68 +/- 0.28 vs 0.91 +/- 0.28 l x min-1 x m-2; p <0.05) and femoral blood flow (0.25 +/- 0.08 vs 0.32 +/- 0.11 l x min-1 x m-2; p <0.05). Changes in splanchnic oxygen delivery and consumption were parallel in the two study groups. In response to dobutamine, gastric pHi did not change (7.30 +/- 0.08 vs 7.31 +/- 0.06; NS), while in the control group, gastric pHi tended to decrease (7.32 +/- 0.04 vs 7.28 +/- 0.06; NS). Systemic oxygen consumption increased in response to dobutamine (141 +/- 11 vs 149 +/- 11 ml x min-1 x m-2; P <0.05) but did not change in the control group. CONCLUSIONS: We conclude that a mismatch between splanchnic oxygen delivery and demand may be present despite stabilization of systemic hemodynamics after cardiac surgery. This is suggested by the parallel changes in splanchnic oxygen delivery and consumption. Dobutamine is likely to improve splanchnic tissue perfusion at this phase.

Acidosis↗
PubMed1996

Definition and detection of alarms in critical care.

Critical care medicine has developed enormously in complexity and even more so in cost over the past twenty years. There has been evidence of remarkable progress in improved outcomes from some conditions, particularly when severely ill patients are treated in well equipped and well managed intensive care units (ICU) which have clear directorship and comprehensive management guidelines and protocols (Zimmermann et al., Crit Care Med 1993; 21:1443-1451). Nevertheless, for some conditions such as severe acute respiratory failure and multiple organ failure, there is considerable debate as to whether there has been any improvement at all (Lee et al., Thorax 1994; 49:596-597. Artigas et al., Adult respiratory distress syndrome, Churchill Livingstone, Edinbugh, London, Madrid, Melbourne, New York, Tokyo, pp. 509-525). Developments in signal processing and monitoring and recording technology have resulted in a vast increase in the quantity of data that is available to clinicians trying to manage critically ill patients (Price, Bailliere's Clin Anaesthesiol 1987; 1:533-556) but there is little evidence that this apparent gain has lead to better clinical decisions or earlier warning of significant instability. One of the tasks of the European Union sponsored IMPROVE group was to attempt to identify significant downward trends in vital parameters sufficiently early to allow clinical intervention to be potent and effective and ultimately improve patient outcome from a wide range of life threatening conditions. The first stage of this task was to define examples of such life threatening deterioration and conduct a survey in representative intensive care units of the incidence of these conditions and the subsequent patient outcomes. This is a preliminary task, the next stage being the gathering of "real time' data from critically ill patients for 24-h sample periods to probe for deteriorating trends and to compile a comprehensive annotated data library of physiological data as a rich resource for future adaptations in signal processing technology and clinical decision support.

Bacterial Infections↗