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H Haljamäe

Publications and source records attributed to H Haljamäe.

At least 55 records · Page 3Linked to original sources
PubMed1990

Cardiac output determinations in the pig--thoracic electrical bioimpedance versus thermodilution.

The accuracy of transthoracic electrical bioimpedance (TEB) for continuous, noninvasive measurement of cardiac output (Qt) in pigs was assessed in comparison with the thermodilution (TD) technique. Using the TEB technique, the different thoracic habitus of the pig had to be corrected for A good correlation with the TD technique was obtained (r = .87; p less than .001; n = 86) using thoracic length value (the measured value plus 25%) in an NCCOM3-R6 cardiodynamic computer for Qt values ranging from 2.9 to 9.8 L/min in pigs weighing from 40 to 75 kg. However, the Qt values given by the NCCOM3 were systematically 11% to 15% higher over the full range of values than the average of NCCOM-3 and TD Qt values. On the basis of the good agreement in the present study between the TEB and TD techniques over a broad range of Qt values, we conclude that TEB offers a valuable continuous, noninvasive alternative to TD for Qt determinations in experimental porcine models.

Animals↗
PubMed1990

Disturbances of blood-flow velocity in the dorsal veins of the hand after vein cannulation and cannula fixation in the anaesthetised patient.

Modifications of the mean blood-flow velocity in the dorsal veins of the hand were assessed semi-quantitatively with continuous wave (CW) Doppler equipment in 32 anaesthetised patients (17 men and 15 women), 23-78 (median = 56) years of age, before and after venous catheterisation with cannula fixation to the skin. Cannulation of the vein caused a 48% reduction in the mean blood-flow velocity and made it impossible to detect any flow with the equipment used in 22% of the patients. A 10% further reduction in the mean blood-flow velocity and in the number of subjects with undetectable blood flow was observed after fixation of the cannulae. Age, small vein diameter, and hyperventilation (end-tidal carbon dioxide less than or equal to 3.5 volume % appeared to be significant factors reducing blood-flow velocities in the cannulated veins. It is concluded that venous catheterisation and fixation of the cannula induce a significant reduction in the blood-flow velocity.

Adult↗
PubMed1990

Patients' experiences of postoperative respirator treatment--influence of anaesthetic and pain treatment regimens.

The influences of premedication, anaesthetic agents, and postoperative sedation and pain treatment regimens on the experiences of postoperative respirator treatment of surgical patients (n = 107) have been assessed. Of the patients, 55% recalled the respirator treatment. Administration of anticholinergic drugs and halogenated anaesthetic agents was found to impair the memory process and reduce the number of recallers, and sedation in the ICU with benzodiazepines was found to decrease the number of discomforts experienced by the recalling patients. Most of the patients who received treatment postoperatively for pain, mainly by epidural administration of local anaesthetic agents and/or morphine, recalled the respirator treatment period (85%), as compared to only 50% of the patients receiving intravenous opioids. The number and type of complaints experienced by patients receiving epidural pain treatment did not, however, differ from those reported by intravenously treated patients, and no significant adverse psychological reactions seemed to occur. It is concluded that the use of mainly regional techniques, when appropriate, for pain treatment of surgical patients needing postoperative ventilatory support seems advantageous. The primary aim of relieving pain from the wound area is achieved, allowing such light intravenous sedation and pain treatment that the possibility of communication and giving comforting reassurance is maintained. Such nursing care may be more efficient in helping the patient to cope with the stressful respirator treatment situation then heavy intravenous sedation and pain treatment regimens.

Anesthetics↗
PubMed1990

A porcine model for acute distal aortic occlusion.

Periarterial and intramural nerves and lymphatics as well as the vascular endothelium may influence pathophysiologic responses to acute arterial occlusion. For study of such pathophysiologic patterns, experimental models resembling the clinical situation are therefore preferable. In this porcine study acute distal aortic occlusion was mimicked by use of a balloon catheter introduced via a vascular graft anastomosed to the lateral aortic wall. Peripheral circulatory disturbance was assessed by measurements of femoral vein blood flow, skin blood flow in the hind foot and oxygen tension in the calf muscle, which verified the degree of ischemia. During the 4-hour ischemic period, repeated arterial and venous blood gas analyses showed increasing acidosis in effluent venous blood from the hind limbs, which after reperfusion slowly normalized. As highly reproducible conditions are achievable with the present experimental model, it can be used for studies of pathophysiologic responses to acute distal aortic occlusion.

Animals↗
PubMed1989

[Risk of central pontine myelinolysis in the treatment of severe hyponatremia].

Central pontine myelinolysis is a life-threatening condition involving the demyelination of axons in certain areas of the brain. It has been shown almost invariably to occur in connection with hospital care. In recent years, a connection has been noted between the rapid restitution of low serum sodium and the development of the condition. In this review, the most recent scientific information is summarized. It is concluded that the risk should always be considered in treating a hyponatremic patient. The serum sodium level should be raised slowly and the acute treatment ended before normal serum sodium levels are reached, ie when the patient is still slightly hyponatremic.

Demyelinating Diseases↗
PubMed1989

Patient experiences during respirator treatment--reason for intermittent positive-pressure ventilation treatment and patient awareness in the intensive care unit.

Patient awareness of intermittent positive-pressure ventilation (IPPV) treatment in the ICU was studied in 304 patients. These ICU patients were divided into three groups: those treated for internal medical diseases (IMD; n = 129), patients admitted after major surgical procedures (MSP; n = 126), and patients treated for trauma (T; n = 49). All patients were interviewed 2 months to 4 yr after IPPV treatment. The IPPV period was recalled by 52% of all patients. The awareness of the treatment was similar in the IMD (51%) and MSP (59%) groups, but was significantly lower in the T group (37%; p less than .01). The ability to recall the IPPV treatment was reduced in patients with head injuries, those unconscious on admittance, and in elderly individuals. Treatment awareness was found to increase with the duration of the IPPV period in the IMD and T groups. Preoperative information of the treatment, given to elective surgical patients in the MSP group, did not increase treatment awareness.

Adult↗
PubMed1989

Assessment of patients' experience of discomforts during respirator therapy.

Patients (n = 158) who had been respirator-treated and who could remember the treatment were retrospectively (after greater than 2 months) interviewed about their experiences. Of all patients, 47% had felt anxiety and/or fear during the treatment. These feelings were intimately related to the experience of agony/panic (p less than .001) and insecurity (p less than .001). Inability to talk and communicate was found to be the dominating reason (p less than .001) for evoking such feelings and also made it difficult for the patients to sleep and rest (p less than .05); no correlation to pain was found. Difficulties to synchronize with the respirator in connection with suctioning also caused feelings of anxiety/fear (p less than .01), agony/panic (p less than .01), and insecurity (p less than .001). Even as long as 4 yr after respirator treatment, most patients (90%) who remember the treatment still recall the situation as unpleasant and stress-evoking. The isolation due to communication difficulties was a greater problem than direct airway-related nursing care activities. This relationship between communication difficulties and severe emotional reactions should be considered in the nursing care of respirator-treated patients.

Adult↗
PubMed1989

Continuous conjunctival oxygen tension (PcjO2) monitoring for assessment of cerebral oxygenation and metabolism during carotid artery surgery.

The clinical value of noninvasive continuous monitoring of conjunctival oxygen tension for assessment of cerebral perfusion during carotid endarterectomy performed under general anaesthesia has been evaluated. The patients (n = 17; mean age 62.5 +/- 1.7 years) were monitored as follows: conjunctival oxygen tension (PcjO2); internal jugular venous oxygen tension at the skull base level (PcijvO2); arterial blood pressure; arterial and internal jugular venous blood gases; acid-base data and lactate, pyruvate levels; end-tidal CO2 concentration. The mean preanaesthetic PcjO2 level of 4.86 +/- 0.40 kPa was significantly lower than PaO2(PcjO2)/PaO2 ratio of 0.48). Following anaesthesia, a larger PcjO2-PaO2 gradient (ratio 0.32) was seen in spite of the hyperoxic situation (FiO2 = 0.40) due to vasoconstriction induced by slight hypocapnia (reduction of PaCO2 from 5.13 +/- 0.08 to 4.64 +/- 0.10 kPa). The carotid artery crossclamping resulted in a rapid and pronounced decrease of PcjO2, while PcijvO2 remained unchanged. No relationship between PcjO2 and stump pressure was found, while a significant correlation (P less than 0.02) between PcjO2 and lactate in effluent venous blood from the brain was demonstrable. It is concluded that PcjO2 monitoring seems a clinically useful trend indicator of cerebral perfusion in the individual patient. Due to large interindividual variations in basal PcjO2 readings and in PcjO2 changes during carotid artery clamping, however, transconjunctival oxygen tension monitoring does not seem to allow early and accurate recognition of impending cerebral ischaemia during carotid endarterectomy, and its routine use therefore seems of limited value.

Adult↗
PubMed1989

Anesthetic risk factors.

Various patient-, surgery-, an anesthesia-related factors probably influence the outcome of surgical procedures. The American Society of Anesthesiologists (ASA) Physical Status Classification System, while a systematic approach to the assessment of anesthetic risk factors, considers only physical status factors and lacks predictive value for individual cases. Other risk-predictive factors such as age and sex of the patient and the type, site, and duration of surgery should also be included. Multifactorial approaches include both patient- and surgery-related variables, and therefore make an individualized risk prediction possible. Although the choice of anesthetic agent does not appear to influence the incidence of complications or operative outcome, anesthetic technique and anesthesiologist skill are factors of some importance.

Anesthesia↗
PubMed1988

Liver metabolic effects of intestinal shock and naloxone treatment in the rat.

The liver metabolic response of rats following a standardized intestinal shock, induced by applying a pressure of 120 cm water on the mesenteric vessels for 60 min, was studied. Immediately prior to the release of the pressure on the vessels saline or naloxone was given either as a single injection or as a continuous infusion. After the reperfusion of the intestine no early disturbances in liver metabolism were found as evidenced from the ATP, glucose and lactate levels in liver biopsies taken 15 min following reflow. Within 60 min of reflow reduction of ATP and increases of glucose and lactate levels occurred. There were no major hemodynamic or liver metabolic differences between saline- and naloxone-treated shocked rats. When saline or naloxone was given as a continuous infusion, the changes in liver metabolism were, however, less severe than those observed in the single injection situation pointing toward a non-specific effect of volume replacement rather than a blockade of opioid receptors. Hepatic hypoxia and/or cellular effects of "shock factors" could be mechanisms of pathophysiologic importance for the disturbed liver metabolism in this shock model.

Acid-Base Equilibrium↗
PubMed1988

Epidural vs general anaesthesia and leg blood flow in patients with occlusive atherosclerotic disease.

Total leg blood flow (plethysmography), skin blood flow (laser-Doppler flowmetry), and haemodynamic stability (MAP, HR, RPP) were studied in vascular (ABI less than 1.0; n = 31) and in non-vascular (ABI greater than 1.0; n = 24) surgical patients during epidural or fentanyl-supplemented general anaesthesia. During epidural anaesthesia significant increases in total leg blood flow were observed in vascular (from 1.9 +/- 0.2 to about 3 ml/100 ml tissue/min) as well as in non-vascular (from 2.5 +/- 0.6 to about 7 ml/100 ml tissue/min) patients and leg blood flow remained high in the postanaesthetic period. During general anaesthesia total leg blood did not increase, either in vascular or in non-vascular patients, and in the postanaesthetic period blood flow values even lower than the initial ones were observed. Skin blood flow increased about 4-fold in vascular as well as in non-vascular patients following both types of anaesthesia. In the immediate postanaesthetic period low flow values were again observed but only in the general anaesthesia groups. In vascular patients no critical redistribution of blood flow within the limb was observed irrespective of the type of anaesthesia. Good haemodynamic stability could only be maintained in the epidural group. It is concluded that epidural anaesthesia seems to offer considerable advantages over general anaesthesia for high-risk vascular patients during arterial reconstructions since better haemodynamic stability and higher leg blood flow can be achieved.

Aged↗
PubMed1987

Renal cell carcinoma with vena cava extension: diagnostic and surgical features of 41 cases.

Vena cava extension of renal cell carcinoma was diagnosed in 33 men and 8 women, 29 of whom had right-sided and 12 left-sided tumours. Angiography was performed in all and cavography in most patients. Computed tomography was available in 16 cases. The tumour thrombus did not reach the diaphragm in 32 patients, and extended above it in 9 cases. Macroscopically, complete cavathrombectomy was performed in 33 patients. All tumours except one were of high grade type (grades III and IV). Serum creatinine and liver enzymes were normal at the first postoperative check-up. The 5-year-survival rate in patients subjected to complete cavathrombectomy was 24%. The 5-year-survival was 33% in patients whose tumours extended to below the diaphragm, 0% in patients whose tumours extended above the diaphragm (NS), 33% in grade III tumours and 0% in grade IV tumours (NS), 33% in patients without evidence of metastases and 0% in patients with preoperative metastases (NS).

Adult↗
PubMed1986

Liver susceptibility to ischaemia in spontaneously hypertensive rats.

Blood loss has previously been shown to be more detrimental for spontaneously hypertensive (SHR) than for normotensive Wistar-Kyoto (WKY) rats. To evaluate whether this decreased tolerance to blood loss is due to disturbances in circulatory control or to alterations in cellular function caused by the hypertensive disease, SHR and WKY were subjected to complete liver ischaemia. During a 45-min period of ischaemia as well as after 4 h of reflow, the liver content of ATP, glycogen, glucose and lactate was determined. Liver ATP decreased to 15% and liver glycogen to 30% of initial levels, while liver glucose increased 6-fold and liver lactate 13-fold during the ischaemic period in both SHR and WKY. Following 4 h of reflow, ATP was restored to 11.5 +/- 1.7 mumol X g protein-1 (56% of initial level) in SHR and to 15.2 +/- 1.3 (76%) in WKY. The levels of lactate and glucose returned to control levels after the reflow period while the glycogen stores were further depleted in SHR as well as WKY. No difference between SHR and WKY in cellular metabolic function during the ischaemic period could thus be demonstrated, and the postischaemic recovery was not significantly different. It is concluded that hypertensive disease does not seem to change the ischaemic tolerance of liver cells to any considerable extent.

Animals↗
PubMed1985

Influence of pre-operative treatment with phenoxybenzamine on the incidence of adverse cardiovascular reactions during anaesthesia and surgery for phaeochromocytoma.

The influence of pre-operative treatment with the alpha-adrenoceptor blocking agent, phenoxybenzamine, on the incidence of adverse cardiovascular reactions during anaesthesia and surgery for phaeochromocytoma was evaluated in a series of 62 patients. Fifty-one of them received pre-operative treatment with phenoxybenzamine and eight of these were also treated with beta-adrenoceptor blocking agents. The median final daily dose of phenoxybenzamine was 160 mg and the median period of treatment 23 days. The evening before surgery and in the early morning on the day of surgery, intravenous infusion of phenoxybenzamine was given to 42 of the patients. Eleven patients operated on between 1956 and 1963 received no specific pre-operative treatment and served as a reference group. The alpha-adrenoceptor blocking treatment resulted in a considerably smoother peroperative course, as evidenced by a statistically significant reduction in the incidence of excessive blood-pressure variations. The blockade was not complete since 69% of the patients had systolic peaks greater than 175 mmHg during surgery. Pre-operative blood transfusions did not significantly affect the incidence of hypotensive episodes. Pre-operative beta-adrenoceptor blockade did not reduce the incidence of peroperative arrhythmia. On the basis of our experience, we recommend that all phaeochromocytoma patients be treated pre-operatively with alpha-adrenoceptor blocking agents.

Adolescent↗