Biomedical subjects
L Lindgren
Publications and source records attributed to L Lindgren.
Extracorporeal immunoadsorption compared to avidin chase: enhancement of tumor-to-normal tissue ratio for biotinylated rhenium-188-chimeric BR96.
UNLABELLED: Based on the biodistribution and kinetics of biotinylated 188Re-chimeric BR96 (chiBR96), the enhancement of the tumor-to-normal tissue (T/N) radioactivity ratio using extracorporeal immunoadsorption (ECIA) was evaluated and compared with that of avidin "chase" in colon carcinoma-isografted Brown Norwegian rats. METHODS: Extracorporeal immunoadsorption (ECIA) was performed 6 or 12 hr after intravenous administration of biotinylated 188Re-chiBR96. Radioactivity redistribution was investigated just after ECIA [8 or 14 hr postinjection of the antibody] and 40 or 34 hr after ECIA performance (48 hr postinjection). Avidin was administered intraperitoneally at 6 hr postinjection. Tumor radioactivity uptake and T/N activity ratios of biotinylated 188Re-chiBR96 were compared using ECIA and avidin chase and were also compared with controls. RESULTS: Both ECIA and avidin chase can rapidly increase the radioactivity tumor-to-blood ratio without significantly interfering with the tumor uptake. ECIA at 8 hr postinjection increased the T/N ratios in blood-rich tissues, such as liver and bone marrow, from 6 and 8 to 10 and 18, respectively. Corresponding T/N ratios at 14 hr increased from 9 and 10 to 24 and 36. In contrast, when avidin chase was used, there were no T/N improvements, except in blood. Moreover, avidin chase caused a significant accumulation of radioactivity in the liver. CONCLUSION: The ECIA approach, with direct removal of unbound circulating biotinylated 188Re-chiBR96, thus can rapidly improve and maintain T/N ratios without overloading the liver with radioactivity, in contrast to avidin chase.
[A study of post-traumatic stress reactions among war refugees based on medical records. A standard model may support the treatment].
A special project designed to aid Bosnian refugees in Stockholm County was initiated and funded by the County Council in February 1994. The present study, a joint endeavour involving the Bosnian Project, the Centre for Trauma and Torture Diagnostics, and the Red Cross Centre for torture victims, was designed to fulfil the following aims: To characterise the patient population in terms of social situation, trauma history, symptoms and treatment; To review accumulated experience at the three centres; To outline and discuss the treatment; and To suggest new avenues for further research concerning refugees and trauma. To obtain comparable material for this retrospective review of case records at the three centres, a special case chart format was adopted, covering pre-war and pre-treatment information on general background, social situation, health status and medication, as well as trauma history, symptoms and treatment. Most patients reported good pre-war health, but at the time of the study exhibited manifest effects of trauma history; 95 per cent reported mental problems, and 39 per cent medical disease or physical disorders. These refugees were thus characterised by manifest post-traumatic stress symptoms and need of treatment. Despite their relatively short time in Sweden, almost all had permanent residence permits and fixed addresses. The absence of a comparable control group precluded comparison with other refugee or normal populations. The findings suggest the need of co-ordination and co-operation between the special facilities available to refugees, and of a standardised format for case records.
Randomized comparison of the neuroendocrine response to laparoscopic cholecystectomy using either conventional or abdominal wall lift techniques.
Increase in plasma renin activity and noradrenaline concentration occur in response to carbon dioxide insufflation during laparoscopic cholecystectomy. In a randomized study the conventional carbon dioxide pneumoperitoneum was compared with the abdominal wall lift method for laparoscopic cholecystectomy, with special reference to neuroendocrine changes and renal function. The total mean(s.d.) volume of carbon dioxide insufflated was 42(23) litres with the conventional method and 9(7) litres with abdominal wall lift (P < 0.001). Mean(s.d.) intra-abdominal pressure after 15 min of insufflation was 11(2) and 3(9) mmHg respectively (P < 0.01). In the conventional group mean(s.d.) plasma renin activity increased slightly from 5.5(2.1) to 6.1(2.0) ng ml-1 during the first 55 min of laparoscopic cholecystectomy. In the abdominal wall lift group plasma renin activity decreased from 5.3(2.7) to 3.8(0.9) ng ml (P < 0.01 between the groups). Plasma antidiuretic hormone concentration increased similarly in both groups. Diuresis was significantly less with conventional pneumoperitoneum during the first 35 min of the operation compared with the abdominal wall lift method (P < 0.001). There were significant increases in plasma noradrenaline concentration in both groups (P < 0.001), but the increase was slightly higher in the conventional group during the first 15 min of insufflation. The abdominal wall lift method with minimal carbon dioxide insufflation was associated with smaller neuroendocrine responses and better preservation of renal function compared with conventional carbon dioxide pneumoperitoneum.
The pharmacokinetics of oxycodone in uremic patients undergoing renal transplantation.
STUDY OBJECTIVE: To determine the pharmacokinetics of oxycodone and the excretion of oxycodone and its metabolites noroxycodone and oxymorphone in uremic patients undergoing renal transplantation. DESIGN: Open study of the pharmacokinetics and excretion of oxycodone. SETTING: IV Department of Surgery, Helsinki University Central Hospital. PATIENTS: 10 uremic patients undergoing renal transplantation and 10 ASA status I patients undergoing general surgery. INTERVENTIONS: Intravenous (IV) oxycodone chloride 0.07 mg/kg was administered 30 minutes before induction of standardized anesthesia. Sampling of blood and urine was conducted for 24 hours. MEASUREMENTS AND MAIN RESULTS: The concentrations of oxycodone and noroxycodone in plasma and the 24 hour urine recoveries of the conjugated and unconjugated forms of oxycodone, noroxycodone, and oxymorphone were measured. Mean elimination half-life was prolonged in uremic patients due to increased volume of distribution and reduced clearance. Interindividual variation was very great. Plasma concentrations of noroxycodone were higher in uremic patients. Significantly smaller quantities of free oxycodone and noroxycodone and both free and conjugated oxymorphone were excreted in the urine in the uremic than in the control patients. CONCLUSIONS: Elimination of oxycodone is impaired in end-stage renal failure.
Gasless laparoscopic cholecystectomy: comparison of postoperative recovery with conventional technique.
We have compared, in a randomized study in 26 patients, immediate and late postoperative recovery after elective laparoscopic cholecystectomy using the gasless, mechanical abdominal wall lift method with conventional carbon dioxide pneumoperitoneum. After the gasless method, tracheal extubation was performed significantly earlier than after the conventional method (P < 0.01). End-tidal carbon dioxide concentrations were significantly higher after pneumoperitoneum for 30 min after operation (P < 0.01). In the conventional group, deviation in Maddox-Wing recordings from preoperative values remained at a significantly higher level during the 3-h recovery room period (P < 0.01). There was a positive correlation between the total amount of carbon dioxide used and duration of drowsiness (r = 0.61, P < 0.001) and the Maddox-Wing deviation (r = 0.62, P < 0.001). Postoperative nausea and vomiting, and right shoulder pain occurred less often after the gasless method (P < 0.05). Late recovery criteria (ability to drink, void and walk) in patients in the gasless group were fulfilled approximately 7 h earlier than in those in the pneumoperitoneum group (P < 0.01). Gasless laparoscopic cholecystectomy resulted in more uneventful and faster immediate and late postoperative recovery than conventional carbon dioxide pneumoperitoneum.
Cardiac failure aggravated by timolol eye drops: preoperative improvement by changing to pilocarpine.
A 73-year-old woman with cardiac dysfunction had several episodes of severe bradycardia and pulmonary oedema when waiting for peripheral vascular surgery. She used timolol eye drops for primary open-angle glaucoma. The first episode of pulmonary oedema occurred two weeks prior to and the second on the day before the planned surgery. There were another two episodes of pulmonary oedema before she was transferred to the Department of Internal Medicine where she had a further two episodes of cardiac failure. After changing timolol to pilocarpine eye drops, the patient's condition was stabilized, and two weeks later surgery and postoperative recovery were uneventful.
Transfusion-related acute lung injury (TRALI) after fresh frozen plasma in a patient with coagulopathy.
BACKGROUND: Transfusion-related acute long injury (TRALI) is due to specific antigen-antibody reaction involving the donor's leucocyte or granulocyte antibodies towards the recipient's antigens. Aggregation in small pulmonary vessels occurs, leading to derangement of permeability. CASE HISTORY: TRALI after transfusion of four units of fresh frozen plasma (FFP) for factor V deficiency prior to elective cholecystectomy is presented. Within a few minutes after the third unit of FFP a florid pulmonary oedema developed. Hypotension and hypoxia with SpO2 83-87% at FiO2 1.0 followed. Prompt monitoring of central haemodynamics revealed a normal cardiac index without pulmonary hypertension. The operation was then conducted as planned. The bilateral pulmonary oedema resolved after 72 hours with ventilatory support. The patient recovered without complications. When tested postoperatively, the second unit of FFP contained granulocyte antibodies and the third unit contained HLA antibodies. The crossmatch of the patient's granulocytes and lymphocytes towards the two donors of the two units of FFP was positive. CONCLUSION: When TRALI is suspected the donor blood has to be tested against the recipient. Ventilatory support of the patient is continued until adequate oxygenation is reached.
Respiratory compliance during orthotopic liver transplantation.
After liver transplantation, respiratory complications are frequent. The purpose of this study was to assess if intraoperative monitoring of respiratory compliance is of clinical value in predicting such complications. Respiratory compliance was continuously monitored with a side-stream respiratory gas flow and pressure sensor (Datex, Helsinki, Finland) at the endotracheal tube in 18 adult patients undergoing orthotopic liver transplantation without veno-venous bypass. Respiratory compliance decreased along with blood volume expansion under anaesthesia before the start of surgery (P < 0.05). Compliance improved as ascites was removed at the beginning of laparotomy (P < 0.001). The highest compliance values were seen during liver surgery. In the patients without ascites preoperatively, compliance was lower at the end of surgery than at anaesthesia induction (P < 0.001). In the patients with ascites, compliance at the end of surgery was equally low as at anaesthesia induction. Compliance at the end of surgery was lower in the patients with bilateral than in those with right-sided or no pleural effusions in the postoperative chest X-rays (P < 0.001). In conclusion, intraoperative monitoring of respiratory compliance is one useful method for clinical use in predicting postoperative bilateral pleural effusions.
Heart rate variability in diabetic and non-diabetic renal transplant patients.
BACKGROUND: Heart rate variability (HRV) has been used to investigate the autonomic modulation of heart rate. Diminished HRV has been observed in diabetic autonomic neuropathy, a condition associated with increased mortality. Uraemia is associated with impaired autonomic function, but reports on the effects of uraemia on HRV are scarce. METHODS: HRV and its circadian variation were studied in 12 diabetic and 11 non-diabetic renal transplantation and in 12 control patients. HRV in time and frequency domains was determined from 24-hour ECG recordings. RESULTS: In the diabetic group, all time domain and frequency domain measures of HRV were markedly reduced (P < 0.05), when compared with the control group, and the circadian variation of HRV was absent. The mean (SD) amplitudes (ms) in the frequency bands were: high frequency: 3 (1), 6 (3) and 15 (3); low frequency: 9 (7), 16 (10) and 25 (8); very low frequency: 14 (8), 23 (12) and 30 (11) in the diabetic and non-diabetic uraemic and in the control patients, respectively. In non-diabetic uraemic patients, a tendency to reduced HRV was observed, but no statistical differences in HRV measures were found when compared with the control group. CONCLUSION: The severe impairment of HRV in patients with end-stage diabetic nephropathy is probably due to autonomic neuropathy and partly also to the co-existing heart diseases. It may be a contributing risk factor for ventricular arrhythmias and sudden death in these patients. Uraemia alone causes similar but less severe changes in HRV.
Dietary salt aggravates cyclosporin A-induced hypertension and nephrotoxicity in spontaneously hypertensive rats: protection by oral magnesium supplementation.
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Postoperative lumbar MR imaging with contrast enhancement. Comparison between symptomatic and asymptomatic patients.
UNLABELLED: PURPOSE AND MATERIAL: Contrast-enhanced MR imaging of the spine after surgery for lumbar disk herniation almost always shows pathologic changes. To investigate to what extent these changes are correlated to patients' actual clinical symptoms, we compared the postoperative MR findings in 19 asymptomatic patients with 42 symptomatic patients (43 levels). METHODS: The asymptomatic patients underwent MR examination one year after surgery. Twenty-six of the symptomatic patients underwent MR one year or less after surgery, and in 16 patients (17 levels) MR was performed more than one year after surgery. RESULTS: Sixteen percent of the asymptomatic and 42% of the symptomatic patients had disk herniation at the level of previous surgery. Most of the herniated disks were found in the symptomatic patients less than one year after surgery. The amount of epidural scar tissue, displacement and thickening of nerve roots, and compression of the dural sac were also studied. Disk herniation as a probable cause of recurrent sciatica was a common finding among symptomatic patients examined one year or less after surgery. In comparing asymptomatic patients and symptomatic patients with more than one year between surgery and MR examination, no significant radiologic differences, including disk herniation, were found.
Extracorporeal immunoadsorption from whole blood based on the avidin-biotin concept. Evaluation of a new method.
This study of 36 rats with rat colon adenocarcinoma transplants was carried out to investigate the efficacy of a new method of whole blood immunoadsorption (WBIA) in removing biotinylated monoclonal antibodies (MAbs) directly from unseparated blood, in order to increase 'the tumor/normal-tissue uptake ratio', as compared with extracorporeal immunoadsorption (ECIA) of antibodies from plasma. Compared with the ECIA system, the overall volume of the WBIA system (comprising only a pump, an adsorption column, a drop-chamber and tubings) was less (3.6 vs. 6.2 ml), and procedure duration 2 h less. The 17 rats undergoing the WBIA procedure, started 12 h after i.v. injection of 4.0-4.5 MBq 125I-BR96-biotin, manifested neither hemolysis nor any other complication; no signs of organ edema were found at dissection; whole body and blood radioactivity values were reduced by 51% and 89.5%, respectively. The WBIA method was as effective as ECIA, but technically simpler, safer and more reliable.
The effect of dextran infusion on antithrombin III concentrations and on platelet function during minor surgery.
The effects of dextran on the antithrombin (AT) III activity and blood coagulation, evaluated with thromboelastography, were investigated in 26 patients (anaesthesia risk class I or II) scheduled for minor surgery under general anaesthesia. In the Dextran group the patients were infused first with dextran 7 ml/kg, then with Ringer's acetate. In the Ringer group, the patients received only Ringer's acetate. In the recovery room fluid therapy was continued with 5% dextrose in water until the first postoperative day. Blood loss and fluid replacement were comparable in the groups. Haematocrit (Hcr) decreased significantly in the Dextran group, and the platelet count decreased in both groups during surgery. The median baseline AT III values were similar in the study groups. In the recovery room, the median AT III value was lower in the Dextran than in the Ringer group, 78% and 92%, respectively (P < 0.05). By the following day, the AT III values had returned near the initial level. After surgery, the maximal amplitude of thromboelastogram was 48 mm in the Dextran group, and 58 mm in the Ringer group (P < 0.05). In conclusion, fluid replacement with dextran resulted in modest and short-lived alterations in blood coagulation.
Cardiac evaluation of liver transplant recipients: QT dispersion in electrocardiogram.
Increased QT dispersion, the interlead variability of the QT interval length in the 12-lead electrocardiogram, reflects uneven ventricular repolarization as a sign of cardiomyopathy. We analyzed QT dispersion in the preoperative electrocardiogram of 100 adult liver transplant recipients and 20 healthy control subjects. In 12% of the liver recipients, QT dispersion was increased above 65 ms (mean + 3SD). Six of these patients had a liver storage disease (haemochromatosis, Wilson's disease or amyloidosis). Five had a history of cardiac disease. Severe intraoperative cardiac complications occurred in three patients with markedly increased QT dispersion (> or = 99 ms). In conclusion, in liver storage diseases the heart may be affected, leading to increased risk of cardiac complications, which might be predicted from increased QT dispersion. Analysis of QT dispersion, a noninvasive inexpensive technique, can be recommended to be included in the cardiac screening of liver transplant candidates.
Enhanced radioimmunotargeting of 125I-labeled L6-biotin monoclonal antibody (MAb) by combining preload of cold L6 MAb and subsequent immunoadsorption in rats.
The present study investigates whether tumor:normal tissue uptake ratios of radiolabeled monoclonal antibodies can be further improved by a combination of extracorporeal immunoadsorption (ECIA) and preload with unlabeled idiotypic monoclonal antibody. Athymic rats, heterotransplanted with human lung carcinoma under the kidney capsule (SR tumor) and i.m. (IM tumor), were divided into four study groups: controls, ECIA, preload, and combined preload+ECIA. The preload+ECIA procedure reduced the whole-body and plasma activity by 48 and 89%, respectively. After such combined procedure, the uptake of 125I-labeled L6-biotin in SR tumors was unchanged, while the uptake in normal tissues was considerably reduced. Tumor (T):bone marrow ratio was then increased by 17.5 times (after ECIA) and by 4.5 times (24 h after ECIA). Similar enhancements were achieved for T:liver and T:kidney ratios. For the IM tumors, the ratios were not as high as for SR tumors. The effects on T:normal ratios of preload+ECIA in combination were synergistic. The combined procedure resulted both in an increased uptake and prolonged persistence of 125I-labeled L6-biotin in the SR tumors and also in a reduction of corresponding uptake values in organs critical for radiation.
The effect of skin incision followed by alfentanil on catecholamine levels and on the T-wave amplitude of ECG during isoflurane anaesthesia.
Haemodynamic, ECG T-wave amplitude and plasma potassium changes and plasma catecholamine responses to skin incision followed by alfentanil were studied in 24 ASA I patients. Propofol and vecuronium were used without anticholinergics for induction of anaesthesia followed by isoflurane in 02/air. End-tidal isoflurane concentration was kept constant (0.7%) for 30 min before the skin incision. Five min after the skin incision alfentanil 30 mu g kg-1 was given. Blood samples for catecholamines and plasma potassium concentrations were drawn from right ventricle of the heart one minute before and after the skin incision and two minutes after alfentanil. Heart rate, systolic and diastolic arterial pressures increased after the skin incision (P < 0.001), and decreased after alfentanil (P < 0.001). Plasma adrenaline and noradrenaline concentrations increased slightly after the skin incision (P < 0.05 and P < 0.01, respectively). Noradrenaline levels continued to increase after alfentanil (P < 0.001) despite totally abolished haemodynamic responses to the skin incision. ECG T-wave amplitude changes, measured as R/T ratio, did not correlate to the changes in plasma catecholamine levels: both rapid increases and decreases in R/T ratio were seen. No plasma potassium changes were seen during the trial. T-wave changes, occurring in seconds after the skin incision, are probably produced by a direct catecholamine release from cardiac sympathetic nerve endings.
Haemodynamic and catecholamine responses to induction of anaesthesia and tracheal intubation in diabetic and non-diabetic uraemic patients.
We have studied cardiovascular and catecholamine responses to induction of anaesthesia and tracheal intubation in 13 patients with diabetic nephropathy, in 12 patients with uraemia of other origin and in 12 ASA I control patients. All uraemic patients were undergoing renal transplantation. Cardiovascular autonomic function tests indicated that severe autonomic neuropathy was common in the diabetic patients; less severe impairment of autonomic function was found in the non-diabetic uraemic patients. The systolic pressor response to intubation was greater in diabetic uraemic patients than in the other groups (P < 0.05). Both uraemic groups had higher plasma catecholamine concentrations than the ASA I patients both before and after induction of anaesthesia. The increased plasma concentrations of catecholamines in the uraemic patients may be a result of impaired clearance of catecholamines and higher sympathoadrenal activity needed to maintain cardiac function. The normal systolic pressor response to tracheal intubation in the uraemic patients indicates that the capacity of the cardiovascular system to respond to a stressful stimulus was preserved in these patients also, in spite of autonomic neuropathy. The greater response in the diabetic group may be caused by increased sensitivity to catecholamines and loss of autonomic control.