No effect of cardiopulmonary bypass on hypnosis in patients anaesthetized with propofol and alfentanil.

BACKGROUND: The effect of cardiopulmonary bypass (CPB) on the level of anaesthetic depth has not been studied previously in a randomized way. METHODS: We assessed the effect of CPB on the propofol needed to maintain a fixed bispectral index score, and on the recovery from anaesthesia in 22 patients undergoing coronary artery bypass graft surgery with CPB (on-pump) compared with 18 patients operated on without CPB (off-pump). Anaesthesia was induced and maintained with propofol and alfentanil. Throughout the procedure, the infusion rate of propofol was adjusted to keep the BIS value at 40 +/- 5. RESULTS: With the off-pump technique, the duration of surgery and anaesthetic administration were significantly greater. The need for propofol in proportion to time was exactly the same in both groups. During anaesthesia and the first 3 h thereafter, the BIS recordings were similar in both groups. No differences were detected in the time to awakening or tracheal extubation. CONCLUSIONS: CPB does not affect propofol requirements or immediate postoperative recovery compared with the off-pump technique.

Myocardial metabolism on off-pump surgery; a randomized study of 50 cases.

OBJECTIVE: To study the inflammatory reaction and myocardial metabolism in off-pump and on-pump coronary artery bypass patients. DESIGN: Fifty coronary artery bypass patients were randomized to off-pump or on-pump operations. Myocardial biopsies were taken to determine myocardial metabolism and inflammation (glutathione (GSH), superoxide dismutase (SOD) and myeloperoxidase (MP)) and plasma samples for indicators of oxidative stress (conjugated dienes (s-BDC), oxidative products of proteins (s-ox-Prot) and low-density lipoprotein (LDL)-total peroxyl radical trapping antioxidant potential (s-TRAP)). RESULTS: s-ox-Prot 10 min was 2.11 +/- 0.75 vs 2.69 +/- 0.60 (p = 0.014), s-TRAP 5 min was 861 +/- 180 vs 969 +/- 192 (p = 0.032) and s-TRAP 10 min 857 +/- 176 vs 985 +/- 166 (p = 0.011), GSH 10 min 0.55 +/- 0.19 vs 0.72 +/- 1.16 (p = 0.007) (off-pump vs on-pump). The monobasic (MB) fraction of the creatinine kinase 24 h after the operation was significantly lower in the off-pump group, 20.5 +/- 24.2 vs 61.8 +/- 84.6 (p = 0.023). CONCLUSION: GSH levels from the biopsies were increased in the perfusion group early in the reperfusion time showing that myocardial tissue was well protected and recovered more rapidly after cross-clamping than after the occlusion of the coronary arteries. However, release of creatinine kinase was lower in the off-pump group showing that cardiopulmonary bypass has more deleterious effects later after the operation.

No impact of a leucocyte depleting arterial line filter on patient recovery after cardiopulmonary bypass.

BACKGROUND: Contact of blood with foreign surfaces in the cardiopulmonary bypass (CPB) circuit induces an inflammatory response and immunosuppression which are associated with several organ dysfunctions following cardiac surgery. The aim of the present study was to evaluate clinical patient recovery after coronary artery bypass surgery (CABG) using CPB with leucocyte filtration or no arterial line filter. METHODS: Sixty patients scheduled for CABG were randomly assigned to undergo CPB with a leucocyte depleting arterial line filter (Pall LG6) or no filter. Total leucocyte count and platelet count were determined before and after CPB. Values for blood urea nitrogen, serum creatine, serum sodium and potassium, serum osmolality, urine creatine, urine sodium and potassium, and urine osmolality were recorded at baseline, at 6 h and 24 h after CPB, and on the 5th postoperative day. Complement status was evaluated by measuring the levels of C3 and C4 before surgery and 24 h after CPB. Need for postoperative inotropic support was recorded, as was oxygen index prior to and after tracheal extubation. Times to awakening and tracheal extubation were noted, as were length of stay at the intensive care unit (ICU) and the hospital. Amount of chest drainage until 24 h and need for red blood cell transfusions were recorded. RESULTS: The level of C3 at 24 h was significantly lower in LG6-patients, but no further differences were detected between the groups in any of the laboratory or clinical parameters except for greater chest drainage in LG6-patients. However, need for red blood cell transfusions was similar in both groups. CONCLUSION: Leucocyte filtration in our elective CABG patients did not have any impact on pulmonary gas exchange, need for postoperative inotropic support, length of postoperative mechanical ventilation, or length of ICU or hospital stay.

Ceftriaxone versus vancomycin prophylaxis in cardiovascular surgery.

The efficacy of antibiotic prophylaxis in cardiac surgery was compared between 97 patients receiving a single 2 g dosage of ceftriaxone and 103 receiving 500 mg of vancomycin i.v. every 6 h for 48 h. The overall infection rate was 13.4% in the ceftriaxone and 10.7% in the vancomycin group. Four (4%) wound infections, including one mediastinitis, occurred in the ceftriaxone group and five (5%) in the vancomycin group, with no statistically significant difference. The findings of this study support the adequacy of a simple single dose of ceftriaxone prophylaxis in cardiac surgery, at least in hospitals with low incidence of vancomycin-resistant staphylococcal infections.

Continuous infusion of nimodipine during coronary artery surgery: haemodynamic and pharmacokinetic study.

A continuous infusion of nimodipine 15 or 30 micrograms kg-1 h-1 was administered from the evening before operation to the second morning after operation to 14 patients undergoing elective coronary artery bypass grafting (CABG) surgery. Nimodipine was tolerated well by all seven patients who received the lower dose. However, of the seven patients who received the higher dose, in two patients the infusion had to be discontinued after induction of anaesthesia and immediately after surgery, respectively, because of excessive vasodilatation and hypotension. At steady state before cardiopulmonary bypass (CPB), total plasma nimodipine concentration was higher than expected on the basis of previous reports in non-surgical subjects. Similarly, mean clearance of nimodipine was lower than predicted, that is 0.53 (range 0.40-0.72) litre kg-1 h-1. Initiation of CPB decreased total plasma nimodipine concentration, but the unbound plasma concentration did not decrease because of the increase observed in the free fraction of nimodipine in plasma. As evaluated in a separate closed extracorporeal circuit, nimodipine was sequestered into the circuit. Addition of stored whole blood to the priming solution attenuated this sequestration. It is concluded that clearance of nimodipine, as assessed before CPB at steady state, was reduced in patients undergoing CABG and receiving a continuous infusion of nimodipine. Using this finding of decreased clearance in designing infusion schemes of nimodipine for cardiac-surgical patients, it should be possible to predict more accurately the desired plasma nimodipine concentration and therefore reduce the possibility of unexpected haemodynamic responses.

Progressive unilateral hypertrophic myopathy: a case study.

A 12-year-old girl had progressive unilateral muscle hypertrophy limited to the sole, tibialis anterior, and biceps femoris muscles. The affected muscles showed complex repetitive discharges by electromyography, necrosis and variation of fiber size upon histopathological examination, and increased metabolic activity in biochemical studies. The findings suggest a myopathic origin, but the actual cause remains unknown.

Extracranial carotid artery aneurysms.

A material of eighteen patients with carotid artery aneurysms is presented. Mean age of the patients was 57.9 +/- 15.1 years. Most of the patients were asymptomatic or had only a pulsating mass on the neck. One patient had stroke and five TIA. Most common etiology was arteriosclerosis. Two patients got contralateral and two ipsilateral hemiparesis, one patient was unconscious immediately after the operation. Shunt was used on four of these patients. Three patients died, two for neurological reasons and one myocardial death. During the follow up time there were no carotid related diseases. Two patients died of cancer and two of heart attacks. Mean follow up time was 78.6 months. Eight patients attended the follow up studies which were performed by duplex scanning or angiography. They were free of neurological symptoms and their carotid arteries were patent.

Bronchial carcinoid: a clinical follow-up study of 33 cases.

Thirty-three bronchial carcinoid tumours operated on in a 22-year period are reviewed. They were histologically verified as typical carcinoids with Grimelius' argryophilic staining (25 cases), electron microscopy (6) and immunostaining for synaptophysin (4). Nineteen were endobronchial and 14 peripheral, intraparenchymal tumours. Lymph-node metastases were present at operation in two patients. Two tumours, in patients with Cushing's syndrome, were hormonally active (one secreting ACTH and the other ACTH and calcitonin). There was one case of multiple endocrine neoplasia syndrome, but none of carcinoid syndrome. During follow-up for 5-18 (mean 8.2) years five patients died of unrelated causes. Only one patient showed distant metastasis (after 15 years in salivary gland and a year later in mediastinal fat). Extensive clinical re-examination was performed on 20 patients, and six others were interviewed. All were well but one, who died of uterine cancer 8 weeks later. Typical bronchial carcinoid is concluded to be of low-grade malignancy and suitable for limited pulmonary resection.

The effect of contact Nd:YAG laser on arterial wall and atherosclerotic plaques. Considerations for angioplasty. An experimental study.

The predictability and reproducibility of the laser effect in regard to depth of penetration and atheroablation are important considerations for clinical laser angioplasty. This study was designed to investigate those effects experimentally. A continuous wave contact laser system (SLT CL60R with an SLT MTR 1.5 sapphire tip) was used to produce a total of 592 lesions on 14 portions of atherosclerotic human aorta and 46 portions of intact pig aorta. Different power (1 to 40W) and time (0.1 to 10 sec.) were used. These tissue specimens were analyzed by an independent pathologist. Penetration and extent of thermal damage were recorded. The measurements were analyzed statistically. Analysis shows that the effect of the laser is reasonably well predictable horizontally (correlations .755 and .699) but not at all in depth (correlation .006).