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K Linko

Publications and source records attributed to K Linko.

At least 37 records · Page 2Linked to original sources

Hemodynamics of the legs and clinical symptoms following regional blocks for transurethral surgery.

In a prospective clinical study we compared the hemodynamics and clinical symptoms following regional blocks and general anesthesia. 115 patients undergoing transurethral resection of the prostate were randomized to spinal (n = 62) and epidural (n = 53) blocks. An additional 10 patients received general anesthesia. Calf arterial flow, determined by strain gauge plethysmography (SGP), was similar pre- and postoperatively in the regional block groups but decreased in the general anesthesia group (p less than 0.05) on the 5th postoperative day compared to the preoperative day. On the 2nd and 5th postoperative days, venous capacity was lower (p less than 0.05) after general anesthesia compared to regional blocks. Antiembolism stockings offered no hemodynamic or clinical advantages. During the hospital stay (screening by Doppler and SGP) and 3 months of follow-up, no deep vein thrombosis or pulmonary embolism was diagnosed. 3 months after the operation, unspecific pain and/or weakness in the legs were reported by 12 patients in the spinal group, while the epidural group remained asymptomatic (p less than 0.01). We conclude that the predictive value of negative Doppler and SGP findings is good and that spinal and epidural blocks are hemodynamically advantageous as compared to general anesthesia.

Anesthesia, Epidural↗

The clinical efficiency of the Portex in-line blood warmer.

The Portex blood warming coil (200/700/000) and water bath (500/111/010) were tested by comparing the body temperatures of two groups of patients undergoing similar operations, but having transfusions of different rate and quantity. The skin and oesophageal temperatures in the massively transfused patients (5-31 units) did not differ significantly from those having minor transfusions (1-5 units). The temperatures were well maintained in both groups. The lowest mean oesophageal temperatures, during the transfusions, were 35.2 +/- 0.2 in the massively transfused patients and 35.4 +/- 0.1 (SEM) in the control group. The warming capacity of the Portex blood warmer was therefore sufficient for our patients. If, however, transfusion rates, higher than those in this study (maximum 96 ml min-1 during the rapid transfusion phase) are needed, a more effective blood warmer may be beneficial.

Anesthesia, General↗

Comparison of epidural and spinal blockade with 0.5% bupivacaine for transurethral surgery.

The suitability of spinal versus epidural blockade for transurethral resection of the prostate was studied in 60 patients randomly allocated to spinal and epidural anaesthesia groups. 0.5% bupivacaine (Marcain, Astra, Sweden) was injected at the L3-L4 interspace, the dose being 3 ml in the spinal group and 19 (16-25) ml in the epidural group. The blood pressure decreased similarly after both epidural and spinal injections, but the heart rate was not significantly altered. No statistically significant differences were found between the groups in any of the variables measured, including blood pressure, heart rate, intraoperative blood loss and per- and post-operative complications. However, altogether eight patients in the epidural group, but none in the spinal group, had to be treated because of hypotension (P less than 0.001). The main advantage of the spinal blockade was a faster and more reliable blockade of the lowest sacral segments, and the main advantage of the epidural blockade was a less pronounced and shorter duration of motor blockade.

Aged↗

Hyperpotassemia during massive blood transfusions.

Eleven of 21 patients having received more than 10 units of whole blood developed hyperpotassemia during the rapid phase of transfusion. The increase in serum potassium from initial values correlated well (r = 0.74) with the rate of the transfusion. Three of the hyperpotassemic patients developed cardiac arrest but no life-threatening arrhythmias were registered in the normokalemic patients. In contrast to most previous studies, transient hyperpotassemia often necessitating aggressive therapy was quite common in our massively transfused patients.

Heart Arrest↗

Ventilatory response to progressive curarization in patients during light halothane, N2O in O2 anaesthesia.

The effects of progressive curarization on spontaneous ventilation were studied in 23 patients during light halothane-nitrous oxide-oxygen anaesthesia. In 11 patients, in whom the end-expiratory CO2 concentration and evoked mechanical response were recorded, increasing curarization caused first a slow CO2 accumulation and later an abrupt ventilatory impairment at a twitch tension of between 5 and 50% of original muscle strength. In 12 patients, in whom the evoked integrated hypothenar EMG, spontaneous frontal EMG and mean frequency and amplitude of the EEG were recorded, the spontaneous frontal EMG and ventilation diminished within 3 min, following the first 5 mg dose of tubocurarine. At this stage muscle strength, indicated by the amplitude of the evoked EMG and the train-of-four ratio, was unchanged. Repeated 5 mg doses of tubocurarine caused an almost linear decrease in ventilation and an increase in end-tidal CO2 concentration without affecting the rate of breathing until the sudden impairment of ventilation that occurred usually after the fourth dose of tubocurarine. The EEG changes during curarization were minimal and no common trend was seen. The results suggest that tubocurarine may be given to anaesthetized patients in a dose which is too small to produce, using the evoked EMG, a detectable neuromuscular block, but is sufficient to cause ventilatory depression without a compensatory increase in the rate of breathing.

Adult↗

Heated humidification in major abdominal surgery.

The influence of heated humidification on body temperature and postoperative shivering was studied in 30 patients undergoing major intra-abdominal surgery. In the control group (I) the anaesthetic gases, administered in a non-rebreathing system, were humidified by a sponge heat and moisture exchanger. In group II the gases were humidified and heated to 37 degrees C and in group III up to 40 degrees C. Anaesthesia, surface insulation and warming of the infusions were standardized. The temperature was registered at the lower oesophagus and the big toe. Shivering and the feeling of cold were estimated at 15 min intervals postoperatively. A good correlation was found between heat gain during the first hour of recovery, the feeling of cold and intensity of shivering. Intraoperative heat loss was minimal in all groups. Heated humidification had no statistically significant effect on the body temperatures or postoperative shivering and thus provided no additional advantage compared to the control group.

Adult↗

Capnography for detection of accidental oesophageal intubation.

The clinical diagnostic signs for detecting inadvertent oesophageal intubation may all be misleading. We therefore tested the practice of recording exhaled carbon dioxide during the intubation procedure as an additional measure for detection of accidental oesophageal intubation. Twenty patients were intubated simultaneously into the trachea and oesophagus and the carbon dioxide concentration was continuously recorded from both sources. Manual ventilation of the lungs always resulted in a typical CO2 curve pattern. Ventilation by mask prior to the intubation obviously resulted in some filling the stomach by exhaled gas in 9 of the 20 patients. In these cases some CO2 could be detected during oesophageal ventilation. As the oesophageal CO2 concentrations were very low initially, compared to the tracheal recordings, and carbon dioxide completely disappeared after a few ventilations into the oesophagus, distinguishing between the tracheal and oesophageal capnography tracings was easy.

Carbon Dioxide↗

Capnography facilitates blind nasotracheal intubation.

Continuous capnography recordings were made during blind nasotracheal intubation of 17 patients breathing spontaneously. The carbon dioxide analyzer (CD 300, Datex Helsinki) was connected to the open proximal end of the endotracheal tube. In addition to the auscultatory findings, capnography gave valuable information about the position of the endotracheal tube during the entire intubation procedure. The low and peaked CO2 waves recorded from the nasopharynx tended to become higher and more flat-topped as the larynx was approached. When the tip of the endotracheal tube erroneously glided behind the larynx (12 of the 17 cases) this was promptly revealed by absence of CO2 in the recording. On the other hand, entrance of the tube into the trachea could always be rapidly detected as typical flat-topped CO2 waves were seen in the capnogram. Thus capnography facilitates orientation during blind nasotracheal intubation and rapidly detects accidental oesophageal intubation. The capnographic recording also is a valuable and reliable additional sign and document of correct endotracheal intubation.

Auscultation↗

Influence of the Taurus radiowave blood warmer on human red cells. Hemolysis and erythrocyte ATP and 2,3 DPG concentrations following warming by radiowaves, microwaves and water bath.

The warming properties of the Taurus radiowave blood warmer were studied. The safety limits were the same as for microwave warming (Haemotherm). Hemolysis was noted in units with a hematocrit over 0.75 or containing less than 300 g of blood. The effects of radiowave, microwave and water bath warming on the erythrocyte ATP and 2,3 DPG concentrations were compared. Statistically highly significant differences were found between all these methods. Warming of blood in a +35 degrees C water bath for 3 min had no effect on these parameters. There was, however, a tendency for ATP and 2,3 DPG levels to decrease after 60 min water bath incubation (+37 and +45 degrees C), but to increase levels following electromagnetic warming depending on the age of the warmed erythrocytes. Thus, electromagnetic radiation appeared to influence the red cell metabolism, which cannot be explained by the effect of temperature alone.

Adenosine Triphosphate↗

In-line blood warming and microfiltration devices. I. Testing of flow and warming properties by pressure transfusion of aggregate-free blood.

Homogeneous microaggregate-free whole blood at +5 degrees C was transfused at constant pressures of 20 and 40 kPa through two micro-filtration and blood warming devices, and the temperature of the blood was recorded before it reached the venous cannula. The flow rates with the Fenwal system were 58 and 139 g/min, whereas the micro-filter MF10B combined with the Portex Coil allowed flow rates of 143 and 224 g/min. The warming capacities of the two warmers were almost equal and this did not prove to be their weak point. The infusion temperature varied considerably during the transfusion. Increasing the priming volume of the coil would raise the mean infusion temperature. A pressure infusor (Fenwal) was tested, and the internal pressures of the blood bag and the infusor were determined separately. The bag pressure differed significantly from the infusor pressure as the blood bag emptied, making the usefulness of the infusor manometer questionable.

Blood Transfusion↗

In-line blood warming and microfiltration devices. II. Influence of blood temperature on flow rate and hemolysis during pressure transfusion through microfilters and transfusion sets.

The influence of blood temperature on flow rate and hemolysis was studied. Homogeneous aggregate-free blood was transfused through six different microfilters and transfusion sets, combined with a large-bore venous cannula (Venflon No. 2) at a constant pressure of 20 kPa. Flow rates and plasma hemoglobin for cold (+5 degrees C) and prewarmed (+37 degrees C) blood were determined separately. Warming the blood from +5 degrees C to +37 degrees C improved the flow from 49 to 86%. The best flow rates with +37 degrees C blood were obtained with surface filters (MF10B, 275 g/l), and the poorest with depth filters (Swank, 179 g/l). However, the transfusion set and venous cannula seemed to have more influence on the total flow resistance. The Fenwal "dry-heat" warmer was found to have a great flow resistance. The pressure transfusion caused only a slight increase in free plasma hemoglobin of cold blood and no increase in prewarmed blood. It seems more practical to warm the entire blood unit before transfusion than to use so-called in-line blood warmers, because prewarming results in a flow rate approximately twice as high as that obtained with coils.

Blood Transfusion↗