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L S Rasmussen

Publications and source records attributed to L S Rasmussen.

At least 19 recordsLinked to original sources

Do blood concentrations of neurone specific enolase and S-100 beta protein reflect cognitive dysfunction after abdominal surgery?ISPOCD Group.

Neurone specific enolase (NSE) and S-100 beta protein have been used as markers of brain damage. We hypothesized that blood concentrations of NSE and S-100 beta protein reflect cognitive dysfunction after abdominal surgery. We studied 65 elderly patients in whom neuropsychological testing was performed before abdominal surgery, at discharge from hospital and after 3 months. Serum concentrations of NSE and S-100 beta protein were measured before surgery and after 24, 48 and 72 h. Serum concentrations of S-100 beta protein increased significantly while NSE concentrations decreased significantly. The increase in S-100 beta protein concentration after 48 h was significantly greater in patients with delirium. No correlation was found between cognitive dysfunction and S-100 beta protein or NSE concentration. We conclude that blood concentrations of S-100 beta protein increase after abdominal surgery and may be related to postoperative delirium.

Abdomen

Does preoperative night pulse oximetry provide a reliable baseline?

BACKGROUND: Postoperative hypoxaemia may be detected by pulse oximetry monitoring of the arterial haemoglobin saturation (SpO2). The SpO2-values obtained on the preoperative night are presumed to represent baseline values for the patients. The aim of this study was to evaluate the possible difference between nocturnal SpO2-values in the patient's home and in the hospital before operation. METHODS: We included 20 patients, 60 years or older, who underwent continuous monitoring of SpO2 on one night in the patient's home and on the night following hospitalisation before surgery. The alarms were turned off and the values were not accessible to the hospital staff. The SpO2 value was stored every 10 s. We described the general oxygen saturation level using the median of all valid values and we calculated the number of valid SpO2-values at 3 levels: above 90%, between 86 and 90%, and below 86%. RESULTS: The number of valid SpO2-values at home and in the hospital were 2186 and 2330, respectively; the median value was 96% on both occasions. Only 0.36% of the values were below 91% on the two occasions and there were no statistically significant differences between the number of SpO2-values at any of the considered levels. CONCLUSION: Arterial oxygen saturation values measured on the preoperative night in the hospital seem reliable as baseline values for elderly patients.

Aged

Do blood levels of neuron-specific enolase and S-100 protein reflect cognitive dysfunction after coronary artery bypass?

BACKGROUND: Neuron-specific enolase (NSE) and S-100 protein have been used as markers for major brain damage. Cognitive dysfunction after cardiac surgery represents subtle brain damage that is detected by neuropsychological testing. We hypothesised that blood levels of NSE and S-100 protein would increase after coronary artery bypass surgery and that the change in blood level would correlate with the change in cognitive function. METHODS: We included 35 elderly patients undergoing coronary artery bypass surgery. Neuropsychological testing was performed before surgery and postoperatively at discharge from hospital and after 3 months using a neuropsychological test battery. Serum levels of NSE and S-100 protein were measured before surgery and postoperatively after 24 h and 48 h. RESULTS: Serum level of both NSE and S-100 protein increased significantly 24 and 48 h after coronary artery bypass. Only the increase in NSE after 24 h was found to correlate with the degree of cognitive dysfunction at discharge from hospital. The increase in S-100 protein after 24 h correlated significantly with the duration of cardiopulmonary bypass. CONCLUSION: NSE seems to be a useful blood marker for early cognitive dysfunction after coronary artery bypass surgery.

Aged

Benzodiazepines and postoperative cognitive dysfunction in the elderly. ISPOCD Group. International Study of Postoperative Cognitive Dysfunction.

Postoperative cognitive dysfunction (POCD) has been attributed to long-acting sedatives. We hypothesized that diazepam and its active metabolites could be detected in blood after surgery and correlated with POCD, 1 week after surgery in elderly patients. We studied 35 patients, 60 yr or older, undergoing abdominal surgery with general anaesthesia, including diazepam. Neuropsychological tests were performed before surgery and at discharge, where blood concentrations (free fraction) of benzodiazepines were also measured. POCD was found in 17 patients (48.6%). Diazepam or desmethyldiazepam was detected in 34 patients; median postoperative blood concentrations were 0.06 and 0.10 mumol kg-1, respectively. In a multiple regression analysis considering age, duration of anaesthesia and blood concentrations of diazepam and desmethyldiazepam, only age was found to correlate with the composite z-score (F test, P < 0.01). The postoperative cognitive dysfunction we found in elderly patients after operation could not be explained by benzodiazepine concentrations detected in blood.

Abdomen

Long-term postoperative cognitive dysfunction in the elderly ISPOCD1 study. ISPOCD investigators. International Study of Post-Operative Cognitive Dysfunction.

BACKGROUND: Long-term postoperative cognitive dysfunction may occur in the elderly. Age may be a risk factor and hypoxaemia and arterial hypotension causative factors. We investigated these hypotheses in an international multicentre study. METHODS: 1218 patients aged at least 60 years completed neuropsychological tests before and 1 week and 3 months after major non-cardiac surgery. We measured oxygen saturation by continuous pulse oximetry before surgery and throughout the day of and the first 3 nights after surgery. We recorded blood pressure every 3 min by oscillometry during the operation and every 15-30 min for the rest of that day and night. We identified postoperative cognitive dysfunction with neuropsychological tests compared with controls recruited from the UK (n=176) and the same countries as study centres (n=145). FINDINGS: Postoperative cognitive dysfunction was present in 266 (25.8% [95% CI 23.1-28.5]) of patients 1 week after surgery and in 94 (9.9% [8.1-12.0]) 3 months after surgery, compared with 3.4% and 2.8%, respectively, of UK controls (p<0.0001 and p=0.0037, respectively). Increasing age and duration of anaesthesia, little education, a second operation, postoperative infections, and respiratory complications were risk factors for early postoperative cognitive dysfunction, but only age was a risk factor for late postoperative cognitive dysfunction. Hypoxaemia and hypotension were not significant risk factors at any time. INTERPRETATION: Our findings have implications for studies of the causes of cognitive decline and, in clinical practice, for the information given to patients before surgery.

Abdomen

Oxidative DNA damage after transplantation of the liver and small intestine in pigs.

Oxidative damage is thought to play an important role in ischemia/reperfusion injury, including the outcome of transplantation of the liver and intestine. We have investigated oxidative DNA damage after combined transplantation of the liver and small intestine in 5 pigs. DNA damage was estimated from the urinary excretion of the repair product 8-oxo-7,8-dihydro-2'-deoxyguanosine (8-oxodG). In the first 1-3 hr after reperfusion of the grafts, 8-oxodG excretion was increased 2.9-fold (1.7-4.1; 95% confidence intervals; P < 0.05). A control experiment included sham surgery with clamping of the suprarenal inferior caval vein in 2 pigs during steady state infusion of 8-oxodG. While the caval vein was clamped, the urinary excretion of 8-oxodG was almost blocked, whereas after removal of the clamp, the excretion returned to and did not exceed the preclamp levels. In a separate experiment with 2 pigs, the elimination of injected 8-oxodG was shown to adhere to first-order kinetics with a clearance and a terminal elimination half-life of approximately 4 ml min-1 kg-1 and 2 1/2 hr, respectively. The injected dose was completely excreted into the urine within 4 hr. It is concluded that substantial oxidative damage to DNA results from reperfusion of transplanted small intestine and liver in pigs, as estimated from the readily excreted repair product 8-oxodG.

8-Hydroxy-2'-Deoxyguanosine

Hepatitis C in dialysis patients: relationship to blood transfusions, dialysis and liver disease.

Antibodies to hepatitis C virus (anti-HCV) were determined in an unselected group of 340 patients with chronic renal failure treated with maintenance dialysis. A second generation hepatitis C virus (HCV) enzyme-linked immunosorbent assay (ELISA) was used and confirmation made by a second generation recombinant immunoblot assay (RIBA). Sixteen patients (4.7%) were anti-HCV positive and 8 (2.4%) were anti-HCV indeterminate. All anti-HCV positive and anti-HCV indeterminate patients had received blood transfusions. No statistically significant differences were found between anti-HCV positive and indeterminate patients considering blood transfusions, dialysis and liver disease. The combined group of anti-HCV positive and indeterminate patients had had more blood transfusions (P < 0.005) and had been on dialysis for a longer period (P < 0.01) compared with anti-HCV negative patients. Further, significant correlation with elevation of transaminases and anti-HCV was observed (P < 0.001). Thirty patients (8.8%) had elevated transaminase levels and 13 (43%) of these were anti-HCV positive or indeterminate. In conclusion, HCV infection accounts for a substantial proportion of liver disease in dialysis patients, probably most often transmitted by blood transfusions but other routes of transmission could not be excluded.

Adolescent

Randomized evaluation of pulse oximetry in 20,802 patients: I. Design, demography, pulse oximetry failure rate, and overall complication rate.

BACKGROUND: Although pulse oximetry is currently in widespread use, there are few data documenting improvement in patient outcome as a result of the use of oximetry. The authors describe the study design, patient demographic findings, data validation, pulse oximetry failure rate, and overall postoperative complication rates in the first large prospective randomized multicenter clinical trial on perioperative pulse oximetry monitoring. METHODS: In five Danish hospitals, by random assignment, monitoring did or did not include pulse oximetry for patients 18 yr of age and older, whether scheduled for elective or emergency operations, or for regional or general anesthesia, except during cardiac and neurosurgical procedures. Operational definitions were established for perioperative events and postoperative complications. The data were collected preoperatively, during anesthesia, in the postanesthesia care unit, and until the day of discharge from the hospital or the seventh postoperative day. RESULTS: Of 20,802 patients, 10,312 were assigned to the oximetry group and 10,490, to the control group. In general, the demographic data, patient factors, and anesthetic agents used were distributed evenly. A slight intergroup difference was found in the distribution of age, duration of surgery, some types of surgery, and some types of anesthesia. The total failure rate of the oximetry was 2.5%, but it increased to 7.2% in patients with American Society of Anesthesiologists physical status 4 (P < 0.00001). In 14.9% of the patients, one or more events occurred in the operating room and 13.5% in the postanesthesia care unit. The overall postoperative complication rate was 9.7%. The total rates of cardiovascular and respiratory complications were 2.78% and 3.50%, respectively. Within the first seven postoperative days, 0.47% of the patients died. Anesthesia was not thought to have been solely responsible for any death, but in 7 patients (1 per 3,365), it was a possible contributory factor. CONCLUSIONS: Despite the finding of a few significant inter-group differences, the randomization was well balanced with a high validity of data. The overall postoperative complication rate was similar to that in other recent morbidity and mortality studies.

Adult

Randomized evaluation of pulse oximetry in 20,802 patients: II. Perioperative events and postoperative complications.

BACKGROUND: The authors describe the effect of pulse oximetry monitoring on the frequency of unanticipated perioperative events, changes in patient care, and the rate of postoperative complications in a prospective randomized study. METHODS: The study included 20,802 surgical patients in Denmark randomly assigned to be monitored or not with pulse oximetry in the operating room (OR) and postanesthesia care unit (PACU). RESULTS: During anesthesia and in the PACU, significantly more patients in the oximetry group had at least one respiratory event than did the control patients. This was the result of a 19-fold increase in the incidence of diagnosed hypoxemia in the oximetry group than in the control group in both the OR and PACU (P < 0.00001). In the OR, cardiovascular events were observed in a similar number of patients in both groups, except myocardial ischemia (as defined by angina or ST-segment depression), which was detected in 12 patients in the oximetry group and in 26 patients in the control group (P < 0.03). Several changes in PACU care were observed in association with the use of pulse oximetry. These included higher flow rate of supplemental oxygen (P < 0.00001), increased use of supplemental oxygen at discharge (P < 0.00001), and increased use of naloxone (P < 0.02). The rate of changes in patient care as a consequence of the oximetry monitoring increased as the American Society of Anesthesiologists physical status worsened (P < 0.00001). One or more postoperative complications occurred in 10% of the patients in the oximetry group and in 9.4% in the control group (difference not significant). The two groups did not differ significantly in cardiovascular, respiratory, neurologic, or infectious complications. The duration of hospital stay was a median of 5 days in both groups (difference not significant). An equal number of inhospital deaths were registered in the two groups. Questionnaires, completed by the anesthesiologists at the five participating departments, revealed that 18% of the anesthesiologists had experienced a situation in which a pulse oximeter helped to avoid a serious event or complication and that 80% of the anesthesiologists felt more secure when they used a pulse oximeter. CONCLUSIONS: This study demonstrated that pulse oximetry can improve the anesthesiologist's ability to detect hypoxemia and related events in the OR and PACU and that the use of the oximeter was associated with a significant decrease in the rate of myocardial ischemia. Although monitoring with pulse oximetry prompted a number of changes in patient care, a reduction in the overall rate of postoperative complications was not observed.

Adult

[Lumbar regional analgesia in patients during antithrombotic treatment. Procedures used at the Danish anesthesiologic departments illustrated by a questionnaire study].

The attitudes of Danish anaesthetists to employment of lumbar epidural analgesia (EA) or spinal analgesia (SA) in patients receiving perioperative antithrombotic therapy was assessed by a questionnaire investigation. EA and SA were absolute or relative contraindications in patients receiving low-dose heparin therapy in 38% and 24% of the departments. The same figures for patients receiving dextran or acetylsalicylic acid therapy were 3-8%. The limiting value for the P-coagulation factors II, VII and X for employing EA and SA varied considerably in the departments questioned. EA and SA were, however, contraindicated in patients receiving regular anticoagulation in the majority of departments. On a national basis, only two confirmed cases of symptom-producing haemorrhage in the spinal canal which could be attributed to thrombosis prophylaxis after SA/EA have been recognized. Both of these developed after regular anticoagulation therapy. The authors do not find any basis for warning against use of EA/SA in patients receiving subcutaneous heparin therapy, dextran or acetyl salicylic acid, unless another predisposition to haemorrhage is present.

Aged

Antithrombotic efficacy of continuous extradural analgesia after knee replacement.

We have studied the effect of extradural analgesia on postoperative venous thrombosis in patients undergoing knee arthroplasty. Forty-eight patients were allocated randomly to receive either general anaesthesia or extradural analgesia with local anaesthetics for 3 days. All patients wore compressive elastic stockings and no anticoagulant drugs were administered. Bilateral venography was performed 10 days after surgery. Continuous extradural analgesia did not impede mobilization of the patients. One case of nonfatal pulmonary embolism occurred in a patient who received general anaesthesia. The use of continuous extradural analgesia resulted in a significant difference in the total incidence of deep vein thrombosis (18% compared with 59% after general anaesthesia (P = 0.02]. The incidence of calf vein thrombosis was 12% compared with 45% after general anaesthesia (P = 0.05).

Adult

Lumbar regional anaesthesia and prophylactic anticoagulant therapy. Is the combination safe?

A survey has been carried out in all Danish anaesthetic departments (n = 80) regarding the attitude towards the use of epidural/spinal lumbar analgesia in patients who were receiving prophylactic anticoagulant therapy for the prevention of thromboembolism. About 60% of the departments used the techniques in patients receiving low-dose heparin and no side effects had been experienced. Spinal and epidural anaesthesia were in general regarded as being contraindicated in patients fully anticoagulated with vitamin K antagonists. In the world literature, the attitude towards the combination is conflicting. No randomised trial has been performed and complications are almost entirely confined to patients fully anticoagulated with vitamin K antagonists. Only one case of an epidural haematoma has been recorded when subcutaneous low-dose heparin was used as thromboprophylaxis.

Aged

Awakening and recovery of simple cognitive and psychomotor functions 2 h after anaesthesia for day-case surgery--total intravenous anaesthesia with propofol-alfentanil versus thiopentone-alfentanil.

Fifty-seven patients undergoing minor out-patient gynaecological procedures were allocated to one of two total intravenous anaesthesia regimes: propofol and alfentanil or thiopentone and alfentanil. Diazepam was given orally as premedication. To assess objectively the quality of recovery, the patients underwent a number of tests pre-operatively and two hours post-operatively. The time to opening of eyes and orientation was equal in both groups, as was the recovery of the tested cognitive and psychomotor functions after 2 h, when the score in both groups had returned to baseline. We conclude that the use of propofol instead of thiopentone for shorter surgical procedures gives no advantage as regards length of stay in hospital.

Adolescent