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Biomedical subjects

K H Olsen

Publications and source records attributed to K H Olsen.

16 recordsLinked to original sources
PubMed2001

Transoesophageal echocardiographic monitoring during paediatric cardiac surgery: obtainable information and feasibility in 532 children.

BACKGROUND: We hypothesized that transoesophageal echocardiography (TOE) performed by the anaesthesiologists would be beneficial for monitoring purposes during paediatric cardiac surgery. We present the results for the first 5 years in 532 consecutive children. METHODS: The probe was successfully inserted in 99% of cases and remained in the oesophagus for 211 min on average (range 10-555 min). RESULTS: Insignificant valve leak, single- or biventricular failure and volume depletion were the most common new findings due to TOE. Changes in inotropic strategy and volume replacement were the most frequent interventions. In 45% of the cases, new information was disclosed and, in a total of 8% of cases, decisive information was provided. Except for tracheal extubation in one child who was uneventfully reintubated, no severe complications were identified. CONCLUSIONS: These data stress the safety and ease of performing TOE in children undergoing cardiac surgery. There is evidence for benefit from TOE findings to potentially enhance the therapeutic basis.

Adolescent↗
PubMed2000

Neurohormonal activation late after cavopulmonary connection.

OBJECTIVE: To determine whether patients with cavopulmonary connection have higher levels of vasoactive/water-salt regulating hormones and if so, whether hormone levels are related to postoperative haemodynamics and postoperative follow up. DESIGN: Cross sectional study. SETTING: University hospital. PATIENTS: 20 patients (New York Heart Association functional class I-II), mean age 11 years (range 4 to 22), were studied at a mean of 2 years (0.5 to 6) after a total cavopulmonary connection (TCPC, n = 12) or a bidirectional Glenn anastomosis (BDG, n = 8). INTERVENTIONS: Cardiac catheterisation was performed and blood samples were drawn. Control blood samples were drawn from 33 healthy children, mean age 12 years (6 to 16). MAIN OUTCOME MEASURES: Plasma levels of angiotensin II, renin, aldosterone, arginine, vasopressin, atrial natriuretic factor (ANF), brain natriuretic peptide (BNP). RESULTS: All neurohormones were significantly increased in both TCPC and BDG patients (p < 0. 05), with a fourfold increase in angiotensin II, renin, and aldosterone, and a twofold increase in vasopressin, ANF, and BNP (compared with healthy controls). There was no correlation between haemodynamic variables and hormone levels. Angiotensin II and renin were inversely correlated with time to follow up. All subjects over 15 years (n = 5) had normal neurohormonal levels. CONCLUSIONS: Neurohormones were raised for years after successful cavopulmonary operations but lower levels were observed with time on follow up. This supports the hypothesis that neurohormonal activation is primarily related to altered postoperative physiology and that adaptation takes place over time.

Adolescent↗
PubMed1991

Comparison of intravenous and topical lidocaine as a suppressant of coughing after bronchoscopy during general anesthesia.

Twenty-four consecutive patients scheduled for fiberbronchoscopy were randomized to receive double-blind either intravenous (1.5 mg/kg) or laryngotracheal (3 mg/kg) lidocaine to evaluate the influence on post-bronchoscopic laryngospasm, pain in the throat and coughing. Plasma lidocaine concentrations were analyzed 5, 15, 30 and 60 min after administration. None of the patients demonstrated laryngospasm or pain in the throat during the first hour after bronchoscopy. Patients receiving topical lidocaine coughed significantly more than patients receiving intravenous lidocaine, with a median number of coughs of 20 compared to 4, during the first hour (P less than 0.01). The plasma lidocaine concentrations were significantly higher after intravenous than after topical administration (P less than 0.001). After intravenous administration the plasma lidocaine concentrations exceeded the accepted level for potential toxicity in five out of 11 patients, but none of the patients developed toxic symptoms and no side-effects were observed.

Administration, Topical↗
PubMed1990

Spinal analgesia with plain 0.5% bupivacaine administered at spinal interspace L2-3 or L4-5.

Forty patients (age range 60-79 yr) undergoing transurethral surgery were allocated randomly to receive 0.5% plain bupivacaine 4 ml at the L2-3 (n = 20) or L4-5 (n = 20) space. The solution was injected over 30 s with the patient in the sitting position. The patient was kept sitting for 2 min, then placed supine and, 5 min later, placed in the lithotomy position. No significant differences were found in onset time, extent and duration of analgesia or duration of motor block.

Aged↗
PubMed1989

[Clinical aspects of spinal anesthesia administered using 0.5% isobar bupivacaine (Maracine) at the L2/L3 or L4/L5 level].

The effect of employing different interspaces for lumbar puncture during spinal anaesthesia was evaluated in 40 patients receiving 4 ml of 0.5% plain bupivacaine at level L2/L3 or L4/L5. No differences were observed in onset, spread or duration of analgesia. Furthermore, we found that only 80% of the patients, independently of the interspace used, had a cephalad spread to T8 and conclude that spinal anaesthesia using plain bupivacaine is not ideal for supraumbilical surgery.

Aged↗
PubMed1989

Plain bupivacaine: 0.5% or 0.25% for spinal analgesia?

Plain 0.5% bupivacaine 3 ml was compared with plain 0.25% bupivacaine 6 ml for spinal anaesthesia during transurethral surgery in 40 patients. The solutions were injected over 30 s at the L3/4 space with the patient in the sitting position. The patient was kept sitting for 2 min, supine for 5 min and then placed in the lithotomy position. No significant differences were found in onset time, extent of cephalad spread, duration of sensory or motor blockade, or side effects. The use of a 0.5% plain solution of bupivacaine did not appear to confer any advantage over the 0.25% solution.

Aged↗
PubMed1989

Stress response and platelet function in minor surgery during epidural bupivacaine and general anaesthesia: effect of epidural morphine addition.

In a randomized study, thirty patients submitted to transarthroscopic meniscectomy were allocated to general or epidural anaesthesia with or without epidural morphine. Threshold concentration of collagen for platelet aggregation did not differ between the groups, but showed a similar pattern of increase, which was significant in the general anaesthesia group. Collagen-induced thromboxane-B2 synthesis was significantly lower in the epidural anaesthesia groups compared with the general anaesthesia group, and the addition of morphine caused a significant fall in thromboxane-B2 synthesis. The mean serum cortisol concentration increased in the general anaesthesia group, and decreased in the epidural groups. The difference between the groups was significant. Epidural morphine administration significantly decreased serum cortisol. During operation a thigh tourniquet was used. The removal of the tourniquet did not influence any of the measured variables. It can be concluded that the adrenocortical system is activated during general and inhibited during epidural anaesthesia. The addition of morphine during epidural anaesthesia further decreases the activity of the adrenocortical system, and the combined regime has an inhibiting effect on platelet function.

Adult↗
PubMed1988

Combination high dose amrinone and dopamine in the management of moribund cardiogenic shock after open heart surgery.

Two patients who suffered severe cardiogenic shock after open-heart surgery were successfully resuscitated with high doses of amrinone and dopamine. Both patients had required cardiopulmonary resuscitation and neither was responsive to more conventional mechanical and pharmacologic intervention. Neither patient suffered any serious side effects and both were eventually discharged from the hospital in good condition. These two case reports suggest the potential for using higher than previously reported doses of amrinone in combination with dopamine for the successful treatment of moribund cardiogenic shock in the post open-heart surgical patient. Further studies are needed to assess whether this high-dose drug combination will be successful in patients who present with severe cardiogenic shock unrelated to the post open-heart surgical setting.

Aged↗
PubMed1985

Verapamil induced increment of oxygen extraction in the arteriosclerotic limb.

The acute effect of intravenously administered verapamil (0.08 mg X kg-1 body weight, mean dose 5.1 +/- 0.7 mg) on oxygen exchange and arterial blood flow (measured electromagnetically) of the lower limb was studied during reconstructive arterial surgery in 17 patients with obliterative arterial disease of the lower limbs. Verapamil increased oxygen extraction in the diseased leg by 12% (from a median value of 28.3 to 31.6 ml X litre-1, p less than 0.01) whereas it had no effect on arterial blood flow. The increment of oxygen extraction after drug administration correlated negatively with the walking distance of the patients (r = 0.69, p less than 0.01). Systolic and diastolic blood pressure decreased significantly by 10% and 6%, respectively, whereas heart rate remained unchanged after the administration of verapamil. The results suggest that verapamil might be beneficial in the treatment of patients with intermittent claudication, despite the fact that no vasodilatation was seen after the drug.

Aged↗
PubMedDate not supplied

Pediatric multiplane transesophageal echocardiography in congenital heart disease: new possibilities with a miniaturized probe.

In recent years, transducers for multiplane Doppler echocardiography have demonstrated their superior imaging performance in adult patients. To date, the size of these probes has limited their use in pediatric patients. In this article, we report our initial experience with a recently developed miniaturized transducer with all conventional imaging and Doppler modalities. The study focused primarily on imaging performance by comparing standard biplane images with those obtained in oblique planes. The investigations were carried out intraoperatively or during interventional catheterization in patients with congenital heart disease. We observed no complications in a study population of 15 children (weight range of 5 to 63 kg and an age range of 96 days to 11 years). The probe was easy to handle and provided excellent images. Additional information was obtained in several cases and documentation of clinical findings was easier because an optimal image plane almost always could be displayed. We concluded that pediatric multiplane Doppler echocardiography has considerably improved investigative performance compared with the conventional monoplane or biplane studies normally available for this age group. In neonates, however, investigation with the multiplane technique is limited by the size of the patient.

Child↗
PubMedDate not supplied

Epitopes on CA 125 from cervical mucus and ascites fluid and characterization of six new antibodies. Third report from the ISOBM TD-1 workshop.

CA 125 is found in body fluids in a variety of molecular weight forms. The largest species are found in normal abdominal fluid and cervical mucus. The present study therefore incorporated CA 125 derived from these sources as well as ascites fluid to investigate if the source of CA 125 influenced epitope characterization. Ascites-derived CA 125 varied in size from about 190 to about 2,700 kD. Cervical mucus-derived CA 125 treated with ultrasound changed its apparent size from more than 20,000 to 700 kD. Epitope mapping of antibodies was not grossly influenced by the size or source of CA 125 used as target. However, low-molecular-weight CA 125, i.e. ascites fractions CA 17/E, CA 17/F and CA 10/7, did show differences in certain assay combinations and cross-inhibition patterns which probably can be explained by steric effects due to the smaller size compared with the most abundant forms of CA 125 present in serum and other body fluids. The specificity of six new monoclonal antibodies to CA 125 was tested by cross-inhibition and immunometric assay combinations and compared to reference antibodies. One antibody, X306, belonged to the OC125-like antibodies. Four antibodies, X52, X75, X325 and VK8, were M11-like. The sixth antibody, 7C12, reacted with an epitope which was difficult to define. This antibody was inhibited by M11-like antibodies and OV197. However, used as an inhibitor, 7C12 inhibited only itself. We grouped it as an OV197-like antibody, but clearly different from OV197. The topography of epitopes was studied by analyzing all antibody pairs in immunoradiometric assays. These results confirmed the grouping of antibodies described above and are in accordance with previous findings that the highest signal is obtained using an OC125-like antibody or OV197 on the solid phase and an M11-like antibody as tracer. The composition of the sample in terms of high- and low-molecular-weight species of CA 125 was measured, with different responses depending on the antibody pair used. This might be one reason for discrepancies between assay results for CA 125 using different assays.

Antibodies, Monoclonal↗