Coenzyme Q10 in patients undergoing CABG: Effect of statins and nutritional supplementation.

BACKGROUND: The hydroxymethylglutaryl coenzyme A reductase inhibitors (statins) are effective cholesterol lowering medications, however, statins may interfere with CoQ(10) biosynthesis. We examined the effect of statin therapy as well as nutritional supplements on plasma, cardiac and skeletal muscle concentrations of CoQ(10). METHODS: Forty patients with left ventricular dysfunction had fasting blood samples collected at baseline and following four weeks of supplementation (150mg/day of CoQ(10)). Cardiac and skeletal muscle biopsies were collected at the time of surgery and frozen in liquid nitrogen until analyzed for CoQ(10) levels by high performance liquid chromatography. RESULTS: Nutrient supplementation significantly increased plasma [(1.8 (1.2, 2.7) vs 0.8 (0.6, 0.94) mug/ml plasma, median+IQR; p=0.001)] and cardiac tissue concentrations of CoQ(10) [(120.5 (76.5, 177.1) vs 87.3 (60.5, 110.8) nmol/g wet weight, p=0.04)]. No effect of supplementation was seen on samples of skeletal muscle from the chest wall. Statin therapy was not found to influence plasma, cardiac or chest wall levels of CoQ(10). CONCLUSION: Nutrient supplementation significantly increased plasma and cardiac tissue levels of CoQ(10) but did not influence chest wall muscle concentrations. Statin therapy did not significantly influence tissue concentrations of CoQ(10). Longer term studies are needed to confirm this observation.

Impact of treating Staphylococcus aureus nasal carriers on wound infections in cardiac surgery.

Staphylococcus aureus is a common cause of postoperative wound infections, and nasal colonization by this organism is an important factor in the development of infections. Treatment with mupirocin can eradicate the organism in the short term, and prophylactic treatment of colonized patients may prevent postoperative S. aureus infections. A double-blind, randomized, placebo-controlled trial was performed to determine whether nasal mupirocin administered pre-operatively to S. aureus carriers reduces the rates of sternal and leg wound infections after cardiac surgery. The study enrolled 263 patients with nasal S. aureus undergoing elective cardiac surgery at St. Michael's Hospital, Toronto, Canada. Patients were assessed for infections in the immediate postoperative period and two months later. Two hundred and fifty-seven patients were included in the intention-to-treat analysis and re-analysed according to the actual treatment applied. Wound infections occurred in 17 (13.5%) mupirocin recipients and 11 (9.1%) placebo recipients (P=0.319), with seven (5.4%) and six (4.7%) sternal infections, respectively. Two (1.6%) wound infections were acquired postoperatively in the mupirocin group, neither of which were caused by S. aureus. The placebo group had three (2.4%) nosocomial wound infections, with two (1.6%) S. aureus bacteraemias (P=0.243). Among patients receiving mupirocin, 106 (81.5%) cleared S. aureus compared with 59 (46.5%) patients receiving placebo (P<0.0001). There was no significant difference between intention-to-treat and actual treatment groups. Prophylactic intranasal mupirocin administered to S. aureus carriers did not reduce the rates of overall surgical site infections by S. aureus, and only showed a trend towards decreased incidence of nosocomial S. aureus infections.

A comparison of patient-controlled sedation using either remifentanil or remifentanil-propofol for shock wave lithotripsy.

UNLABELLED: Patient-controlled sedation (PCS) has been used for extracorporeal shock wave lithotripsy (SWL) because it allows for rapid individualized titration of anesthetics. Because of its sedating effects, the addition of propofol to remifentanil may improve patient tolerance of SWL with PCS. One hundred twenty patients were randomly assigned to receive remifentanil 10 microg or remifentanil 10 microg plus propofol 5 mg for PCS with zero-lockout interval. Nine patients in the Remifentanil group and three patients in the Remifentanil-Propofol group required additional sedatives to complete their SWL (P = 0.128). Compared with the Remifentanil group, the Remifentanil-Propofol group required less remifentanil, had a decreased incidence of postoperative nausea and vomiting, and had a better overall satisfaction level. However, they had an increased incidence of transient apnea and oxygen desaturation. The incidence of apnea was 15% in the Remifentanil group and 52% in the Remifentanil-Propofol group (P < 0.001). All patients were able to move themselves to the stretcher at the end of SWL, and median time to home discharge was <70 min in both groups. Both remifentanil and remifentanil-propofol were useful for PCS during SWL. IMPLICATIONS: The addition of propofol to remifentanil improves patient satisfaction and decreases postoperative nausea and vomiting. However, it causes more respiratory depression than remifentanil alone. When remifentanil-propofol is used with patient-controlled sedation, appropriate monitoring and a minimum 1-2 min lockout interval is required.

Hemodynamics and early performance of the St. Jude Medical Regent aortic valve prosthesis.

BACKGROUND AND AIM OF THE STUDY: The St. Jude Medical (SJM) Regent heart valve is a new bileaflet prosthetic valve modified from the currently marketed SJM mechanical valve, with a modified external profile that results in a larger geometric orifice area without changing the existing design of the pivot mechanism or blood contact surface areas. The aim of the present study was to report the early hemodynamic and clinical results of an on-going multicenter trial investigating the clinical performance of the Regent mechanical aortic valve prosthesis. METHODS: The early results from 204 patients at 11 centers in North America and Europe who underwent implantation of a Regent mechanical aortic valve prosthesis are described. Clinical status was prospectively recorded, and echocardiography with Doppler performed at hospital discharge, and at two and six months and one year postoperatively. RESULTS: Follow up to date is 109.3 patient-years (average follow up 0.5+/-0.4 years per patient; range: 0 to 1.7 years). NYHA class improved for the group, and there were low rates of clinical adverse effects. Echocardiographic mean pressure gradient at six months was 13.8+/-10.3, 7.4+/-4.1, 5.4+/-3.2, 5.2+/-2.8, 3.4+/-2.3 and 3.6 mmHg, respectively, for 19, 21, 23, 25, 27 and 29 mm valves; effective orifice area was 1.5+/-0.6, 2.0+/-0.7, 2.4+/-1.0, 2.5+/-0.7, 3.6+/-1.4 and 4.8 cm2, respectively. There was a statistically significant decrease in left ventricular mass index between early postoperative (169.1+/-57.7 g/m2) and six months follow up (137.2+/-42.7 g/m2, delta = -30.1+/-42.5 g/m2, p <0.0001). CONCLUSION: The SJM Regent aortic valve has excellent associated hemodynamics with rapid and significant left ventricular mass regression. In all cases of adverse events, rates fell within Objective Performance Criteria guidelines. Long-term clinical assessment is on-going.

Use of "BioGlue" in aortic surgical repair.

A new bioadhesive (BioGlue, Cryolife Inc, Kennesaw, GA) was recently introduced for surgical use in thoracic aortic surgical repair. We describe our early experience and our suggested method of repair.

Effect of aortic cannula characteristics and blood velocity on transcranial doppler-detected microemboli during cardiopulmonary bypass.

OBJECTIVES: Cerebral microemboli are responsible to a large extent for the neuropsychiatric deficits after cardiac surgery. Differences in cannula size during cardiopulmonary bypass (CPB) will result in different velocities of blood exiting the aortic cannula. This study determined whether the number of transcranial Doppler (TCD)-detected emboli in the middle cerebral artery (MCA) during CPB correlated with blood speed or the direction of flow as determined by the shape of the aortic cannula. DESIGN: Patients were studied prospectively for evidence of TCD-detected emboli. If patients met the inclusion criteria, the choice of cannula was determined by surgical preference. SETTING: All studies were conducted at a single tertiary care academic cardiac surgery hospital by a single observer. PARTICIPANTS: Thirty-two patients undergoing first-time elective aortocoronary bypass surgery who were free of neurologic dysfunction or peripheral vascular disease and weighed 60 to 85 kg were studied. Patients who had other concurrent cardiac operations or who were in cardiogenic shock were excluded. INTERVENTIONS: Three aortic cannula types for elective aortocoronary bypass surgery were used: 24F curved (n = 19), 24F straight (n = 6), and 22F straight (n = 7), with internal diameters (IDs) of 7.2, 6.6, and 5.9 mm, respectively. TCD-detected emboli were identified in the MCA. MEASUREMENTS AND MAIN RESULTS: The rate of TCD-detected emboli (0.02 to 11.4 emboli per minute) was not related to the velocity of blood (46 to 77 cm/s) and was not affected by the choice of either a straight or curved aortic cannula. CONCLUSIONS: The choice of a straight or curved aortic cannula or of a 24F versus 22F cannula may not be important with respect to the number of cerebral microemboli.

Distal sciatic nerve compression by a popliteal artery aneurysm.

A 77-year-old man developed progressive sensory and motor symptoms in the right lower leg. Examination showed neurological deficits in the distribution of the right tibial and common peroneal nerves. Swellings in both popliteal fossae were palpated. Investigation showed these to be large thrombosed aneurysms. On surgical examination on the right, the aneurysm was found to be compressing the distal sciatic nerve.

Clagett open-window thoracostomy in patients with empyema who had and had not undergone pneumonectomy.

Patients with empyema not responding to simple chest-tube drainage and antibiotic therapy have been managed by a "Clagett"-type procedure that consists of open-window thoracostomy, antibiotic irrigation and closure of the window. The results of such treatment were reviewed. Of the 103 patients with empyema treated between 1967 and 1983, 41 underwent open-window thoracostomy. Twenty-eight (group 1) had empyema after pneumonectomy, 13 (group 2) did not; however, 9 of the 13 in group 2 had undergone lobectomy. The mean follow-up was 46 months for group 1 and 42 months for group 2. When surgical closure of the open-window thoracostomy was attempted, the success rate in group 1 was 85% for those without concomitant bronchopleural fistula, but only 36% in patients with a fistula. In group 2 the respective success rates were 50% and 57%. Unsuccessful closure resulted in chronic fistulas in four patients in each of the two groups. Six deaths in group 1 and two in group 2 were related to the original disease, but one was an operative death. These results demonstrate both the effectiveness and limitations of open-window thoracostomy in the management of these difficult cases.

Life salvage with fibrin glue in three cases of exsanguinating hemorrhage.

Fibrin glue, although widely used in Europe for a decade, has not been commercially available in North America because its fibrinogen component is obtained from multiple, pooled, human blood donors with the subsequent increased risk of blood transmissible diseases. Techniques developed recently to isolate fibrinogen from single-donor plasma will circumvent these potential hazards. In Canada the use of fibrin glue has not been widespread even though biologic fibrin glue can be made from components readily available within most hospitals. Equal amounts of cryoprecipitate from fresh frozen plasma and bovine thrombin will combine within 2 minutes to form the fibrin glue. Simultaneous injections of each component at bleeding sites form a film of the glue that will effectively control even small arterial bleeding. The authors present three case reports to illustrate how use of the glue can save lives in cases of exsanguinating hemorrhage. They discuss the multiple applications of the fibrin glue which they believe will soon be part of the armamentarium of all Canadian surgeons.

Wedge resection as an alternative procedure for peripheral bronchogenic carcinoma in poor-risk patients.

Although lobectomy is the procedure of preference for patients with peripheral, clinical Stage I bronchogenic carcinomas, wedge resection of the tumor may be a satisfactory alternative in poor-risk patients. Between 1965 and 1982, 197 patients with peripheral bronchogenic carcinomas were operated upon. Clinical staging was established by radiography, bronchoscopy, and mediastinoscopy. Ninety-seven patients underwent lobectomies and 100 had wedge resections. The decision to perform the wedge resection was made preoperatively in the majority of cases based on the assessment of operative risks. Compared to lobectomy patients, those who had wedge resections were older (70.3 +/- 0.5 versus 64.9 +/- 0.5 years, p less than 0.001) and had a lower 1 second forced expiratory volume (1.56 +/- 0.03 versus 1.94 +/- 0.03 ml, p less than 0.001), a lower arterial oxygen tension (70.5 +/- 1.1 versus 75.6 +/- 1.2 mm Hg, p less than 0.01), and a higher arterial carbon dioxide tension (41.7 +/- 0.6 versus 38.7 +/- 0.3 mm Hg, p less than 0.001). Despite their compromised preoperative respiratory functional status, the wedge resection group had a 30 day operative mortality (3% versus 2.1%) and morbidity comparable to those of the lobectomy group. Actuarial life-table analysis indicates the cumulative survival rate at 2 years after operation to be virtually identical between wedge and lobectomy groups (72% versus 74%), and even at 6 years the differences in survival rates (69% versus 75%) were not statistically significant. We conclude, therefore, that by performing wedge resections in selected poor-risk patients, one may reduce the operative mortality and morbidity to an acceptable range without seriously compromising their long-term survival.

Single-layer large-bowel anastomosis: a report of 250 cases.

Single-layer mucosa-excluding intestinal anastomoses involving the large bowel were evaluated in 249 patients (250 procedures). All patients operated on electively had mechanical bowel preparation but not all received antibiotics. Forty-nine anastomoses were performed as part of emergency procedures in which antibiotics were given intravenously. Three leaks were noted in two patients, a rate of 1.2%. There were no deaths attributable to anastomotic dehiscence. These results compare favourably with both hand-sewn and stapled anastomoses described in the literature.

The effect of pretransplant platelet transfusions on renal allograft survival and sensitization in dogs.

Mongrel dogs were given either whole blood (50 ml) or platelets prepared from 50 ml blood intravenously on three occasions before transplantation of a kidney from a different donor to that of the blood or platelets. All dogs were given azathioprine and prednisolone after transplantation. 60 X 10(8) platelets were obtained from 50 ml blood and the leucocyte contamination was less than one leucocyte per 10(5) platelets. The mean survival of kidney allografts in non-transfused dogs was 11.6 days (10 dogs), in dogs pretreated with whole blood 26.6 days (5 dogs), and in dogs pretreated with platelets 29.2 days (5 dogs). Sensitisation occurred in 3 of 5 dogs given whole blood and in 2 of 5 dogs given platelets. Thus pretreatment with a relatively pure preparation of platelets will produce prolongation of survival of third party renal allografts in mongrel dogs given azathioprine and prednisolone, comparable to that produced by whole blood. However, sensitisation was produced by the platelet preparation, presumably due to the minimal leucocyte contamination, which might also be responsible for the suppressive effect of this platelet pretreatment protocol.