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Biomedical subjects

J Takala

Publications and source records attributed to J Takala.

At least 145 records · Page 8Linked to original sources
PubMed1994

Moderate carnitine depletion and long-chain fatty acid oxidation, exercise capacity, and nitrogen balance in the rat.

Carnitine plays a central role in lipid metabolism by transporting long-chain fatty acids into the mitochondria for beta-oxidation. Reduction of carnitine concentration does not automatically imply that functional carnitine deficiency exists with direct consequences on energy metabolism. In our experimental model, we reduced tissue concentrations of carnitine to levels that are comparable to those in patients with various metabolic disorders with secondary carnitine deficiency and did a study on the in vivo effects of moderate carnitine depletion on palmitate oxidation, exercise capacity, and nitrogen balance. Thirty rats were divided into a carnitine-depleted group (group I) and pair-fed controls (group II). Carnitine depletion resulting in a 48% reduction of tissue carnitine concentrations was induced by feeding ad libitum a carnitine-free oral diet consisting of parenteral nutrition solutions. Palmitate oxidation was measured by collecting expired 14CO2 after an intraperitoneal injection of [1-14C]palmitate, and exercise capacity was determined by having the rats swim to exhaustion. Despite the 48% depletion of carnitine in serum, muscle, and liver, there were no differences in cumulative palmitate oxidation in 3 h (group I, 40 +/- 7%; group II, 37 +/- 9% of injected activity), swimming time to exhaustion (group I, 8.1 +/- 2.8 h; group II, 7.7 +/- 3.6 h), or nitrogen balance (group I, 1.1 +/- 0.5 g of nitrogen/kg/d; group II, 1.2 +/- 0.5 g of nitrogen/kg/d). We conclude that carnitine depletion of 48% has no effect on palmitate oxidation, exercise capacity, or nitrogen balance in the rats studied.

Animals↗
PubMed1994

Hypermetabolism and efficiency of CO2 removal in acute respiratory failure.

OBJECTIVE: To assess the effect of hypermetabolism, dead-space ventilation, and parenteral nutrition on the minute ventilation requirement in mechanically ventilated patients. DESIGN: A retrospective analysis of data collected in study protocols unrelated to the present study. SETTING: A medical-surgical intensive care unit in a tertiary care center. PATIENTS: One hundred eleven mechanically ventilated patients were studied during volume-controlled ventilation. MEASUREMENTS: Gas exchange measurement by indirect calorimetry and arterial blood gas analysis. METHODS: Minute ventilation (VE), carbon dioxide production (VCO2), and respiratory exchange ratio (RER) were measured with indirect calorimetry. Arterial CO2 tension was sampled at the end of the measurement, and alveolar ventilation (VA), deadspace to tidal volume ratio (VD/VT) and predicted resting VCO2 were calculated. The VE demand at a standard PaCO2 was calculated and the contribution of the observed hypermetabolism and increased VD/VT was identified. In a subgroup of patients, the effect of initiating parenteral nutrition on the VE demand was assessed. There were four study groups: multiple trauma, sepsis, ARDS, and postoperative open-heart surgery patients. MAIN RESULTS: A combination of hypermetabolism and increased dead-space was observed in 67 of the 111 patients. Increased VCO2 accounted for 69 percent of the excess VE demand in trauma, 67 percent in sepsis, 58 percent in postoperative patients, and 56 percent in ARDS. Parenteral nutrition with a caloric intake matching measured resting energy expenditure (REE) did not increase VCO2 or the demand for VE. CONCLUSIONS: Increased VCO2 is the main cause of increased VE demand in the majority of mechanically ventilated ICU patients. Parenteral nutrition at energy intakes close to actual REE does not increase the ventilatory demand.

Acute Disease↗
PubMed1994

Saline PCO2 is an important source of error in the assessment of gastric intramucosal pH.

OBJECTIVE: To determine whether the measurement error of saline PCO2, using blood gas analyzers, is relevant for the interpretation and clinical use of the gastric intramucosal pH measurement. DESIGN: A comparison of four different blood gas analyzers (ABL-520, Ciba Corning, IL-1302, and Nova), using tonometered saline as the reference. SETTING: Clinical laboratory of a university hospital intensive care unit. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The bias and the precision of each blood gas analyzer was determined for measurements of PCO2 in saline samples. These samples had been balanced to PCO2 levels of 30, 45, and 68 torr (4, 6, and 9 kPa, respectively). In addition, the effect of buffering the saline was evaluated. The bias of the PCO2 measurement increased (p < .001) at the higher PCO2 levels. The bias ranged from -5.2 to -25.9 torr (-0.69 to -3.45 kPa) at a PCO2 of 45 torr (6 kPa) and from -5.2 to -33.1 torr (-0.69 to -4.41 kPa) at a PCO2 of 68 torr (9 kPa), and there was a significant (p < .001) analyzer-PCO2 level interaction. The type of the analyzer also influenced the bias (p < .001). The Nova analyzer underestimated the PCO2 by 50% to 60%. The other analyzers underestimated the PCO2 by 5% to 19%. The use of the buffer reduced the bias of all analyzers (p < .001). Based on the precision of the saline PCO2 measurement, a difference in gastric intramucosal pH of 0.06 pH units can be reliably detected at a PCO2 of 45 torr (6 kPa) by all analyzers, with the exception of the Nova analyzer. CONCLUSIONS: Measurement of saline PCO2 is an important source of error in the assessment of gastric intramucosal pH, and the error depends on both the analyzer used and the actual PCO2 level. Direct comparison of pH values obtained by different analyzers is not valid. Changes in gastric intramucosal pH of 0.06 pH units can be detected by most analyzers in the clinically relevant PCO2 level.

Analysis of Variance↗
PubMed1993

Does alveolar recruitment occur with positive end-expiratory pressure in adult respiratory distress syndrome patients?

We studied the effects of positive end-expiratory pressure (PEEP) (2 to 14 cm H2O) on alveolar recruitment (Vrec), static respiratory compliance, and end-expiratory lung volume (EELV) in nine sedated, paralyzed, mechanically ventilated adult respiratory distress syndrome patients. Positive end-expiratory pressure was applied in increasing and decreasing steps of 2 cm H2O. Flow, tidal volume, and airway pressure were measured. We used the rapid airway occlusion technique to determine static end-inspiratory elastic recoil pressure of the respiratory system (Pst, rs) and intrinsic PEEP (PEEPi). The changes in EELV were measured with respiratory inductive plethysmography. Alveolar recruitment was estimated as the difference in lung volume between PEEP and zero end-expiratory pressure (ZEEP) for the same end-inspiratory Pst, rs (20 cm H2O). We found that (1) Vrec with PEEP up to 14 cm H2O was in general rather small and was absent in two patients; (2) all patients exhibited PEEPi at ZEEP (5.6 +/- 1.0 cm H2O) and little change in EELV and Vrec was achieved until the external PEEP exceeded PEEPi; (3) if end-inspiratory Pst, rs is high at ZEEP, there is little or no alveolar recruitment with PEEP; and (4) Vrec and EELV were slightly higher during stepwise deflation than stepwise inflation with PEEP, except at ZEEP where EELV did not change after inflation-deflation runs with PEEP.

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

Volume-controlled inverse ratio ventilation: effect on dynamic hyperinflation and auto-PEEP.

The effects of inverse ratio ventilation (IRV) and PEEP on dynamic hyperinflation and auto-PEEP were studied in sedated, paralysed patients with adult respiratory distress syndrome (ARDS) (n = 9) and in 10 postoperative patients after coronary artery by-pass (CABG). During volume-controlled mechanical ventilation with constant tidal volume (V(T) 12 ml.kg-1) and respiratory rate (12.min-1), two consecutive experiments were carried out: (1) with constant I:E ratio PEEP was increased in steps of 2 cmH2O (0.2 kPa) from 0 to 12 cmH2O (0 to 1.2 kPa) and (2) with no PEEP I:E ratio was changed stepwise from 1:4 to 4:1. Flow, V(T), peak airway pressure (Pmax) and static end-expiratory pressure (PEEPtot) were registered. PEEPtot was measured while occluding the airway in the end-expiration. The changes in the end-expiratory lung volume (EELV) were measured with respiratory inductive plethysmograph. We found that: (1) increasing PEEP and IRV caused a similar increase in EELV and PEEPtot in ARDS, but in CABG the increase in EELV was greater with PEEP; (2) at the same PEEPtot the increase in EELV was similar with PEEP and IRV in both groups; and (3) the reduction in Pmax was marginal during IRV. We conclude that the effect of reduced expiratory time on end-expiratory lung volume and pressure during volume controlled IRV is similar to the use of PEEP.

Airway Resistance↗
PubMed1993

The relationship between mental health and drug use.

The aim was to examine the relationship between mental health and use of different kinds of drugs. The study was a cross-sectional survey of a total population aged 45-69 years, conducted in 2 municipalities in southwestern Finland. Altogether 1821 people (80% of those invited), 815 men and 1006 women, took part in the screening. The subjects were examined by a questionnaire mailed beforehand and checked in a personal interview. The questionnaire contained questions about the currently used drugs and Goldberg's questionnaire on mental health. Half of the people examined used prescribed drugs currently, more women used drugs than men, and the use of drugs increased with age. Mental symptoms measured with the Goldberg Index appeared in one fifth of the subjects, showing a slight increase with age. Men with mental symptoms showed a fourfold psychotropic drug use compared with the men without mental symptoms. The women with mental symptoms showed a threefold use of psychotropic drugs compared with the women without mental symptoms. Similar differences were found also in other drug groups, for example cardiac glycosides, other cardiovascular drugs, analgesics and drugs for respiratory and digestive organs. Persons with mental disorders showed a high tendency to drug use, also when those drugs had no direct attachment to the mental problem. Men seemed more liable to somatization of mental problems than women.

Age Factors↗
PubMed1993

Use of primary health services in sparsely populated country districts by patients with musculoskeletal symptoms: consultations with a physician.

STUDY OBJECTIVE: To examine the extent to which people consult health centre doctors about various musculoskeletal symptoms and to identify those groups of patients who are responsible for the main workload in primary health care caused by musculoskeletal complaints. DESIGN: A cross sectional investigation based on case records of people who visited health centre physicians. SETTING: The population of six Finnish health centre districts (93,000 inhabitants, 64 physicians' posts in primary care centres). SUBJECTS: 6526 patients (7634 visits) who consulted a physician at any of six health centres during a two week period, of which 1380 consulted for musculoskeletal symptoms. MEASUREMENTS AND MAIN RESULTS: The reasons for the visits were abstracted from the case records and were analysed by cross tabulation. The rate of people visiting for musculoskeletal symptoms during a two week period was on average 15 per 1000 inhabitants. It was highest in men aged 45-54 years (25/1000) and in women aged 55-64 years (26/1000); the rate fell to the average in men over 54 and women over 64 years. Patients with musculoskeletal symptoms accounted for 21% of all patients and 27% of those over 15 years of age. Low back pain was the most common reason for consultation in men aged 25-54 years, while for women aged 35-74 years, the most common reason was neck and shoulder pain. CONCLUSIONS: Over one quarter of adults visiting a health centre doctor do so because of musculoskeletal disorders. This fact must be considered when developing health care services and organising basic education and further in-service training for doctors.

Adolescent↗
PubMed1992

Oxygen transport in septic shock.

Septic shock is an acute impairment of tissue perfusion, characterized by hypotension, low systemic vascular resistance and increased blood levels of lactate. Myocardial dysfunction is common despite hyperdynamic circulation, and may limit the patient's ability to respond to increased tissue oxygen demand. The treatment of hypotension necessitates the use of sympathomimetic drugs, which may compromise regional tissue perfusion despite overall stabilization of hemodynamics. The disproportionately high splanchnic oxygen demand in sepsis makes the splanchnic region susceptible to tissue hypoxia, which may contribute to the development of multiple organ failure in septic shock. Since the changes in regional oxygen transport do not necessarily parallel changes in systemic oxygen transport, the effects of vasoactive drugs on regional blood flow in sepsis should be studied in more detail.

Hemodynamics↗
PubMed1992

Effect of carnitine loading on long-chain fatty acid oxidation, maximal exercise capacity, and nitrogen balance.

Carnitine has a potential effect on exercise capacity due to its role in the transport of long-chain fatty acids into the mitochondria for beta-oxidation, the export of acyl-coenzyme A compounds from mitochondria and the activation of branched-chain amino acid oxidation in the muscle. We studied the effect of carnitine supplementation on palmitate oxidation, maximal exercise capacity and nitrogen balance in rats. Daily carnitine supplementation (500 mg.kg-1 body mass for 6 weeks) was given to 30 rats, 15 of which were on an otherwise carnitine-free diet (group I) and 15 pair-fed with a conventional pellet diet (group II). A control group (group III, n = 6) was fed ad libitum the pellet diet. Palmitate oxidation was measured by collecting 14CO2 after an intraperitoneal injection of [1-14C]palmitate and exercise capacity by swimming to exhaustion. After carnitine supplementation carnitine concentrations in serum were supranormal [group I, total 150.8 (SD 48.5), free 78.9 (SD 18.4); group II, total 170.9 (SD 27.9), free 115.8 (SD 24.6) mumol.l-1] and liver carnitine concentrations were normal in both groups [group I, total 1.6 (SD 0.3), free 1.2 (SD 0.2); group II, total 1.3 (SD 0.3), free 0.9 (SD 0.2) mumol.g-1 dry mass]. In muscle carnitine concentrations were normal in group I [total 3.8 (SD 1.2), free 3.2 (SD 1.0) mumol.g-1 dry mass] and increased in group II [total 6.6 (SD 0.5), free 4.9 (SD 0.9) mumol.g-1 dry mass].(ABSTRACT TRUNCATED AT 250 WORDS)

Analysis of Variance↗
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↗