The impact of the duration of mechanical ventilation on the respiratory outcome in smokers undergoing cardiac surgery.

STUDY OBJECTIVE: To determine the impact of the duration of mechanical ventilation on the rate of pulmonary complications in smokers undergoing cardiac surgery. METHODS: Retrospective analysis of 2163 patients who underwent elective cardiac surgery between September 1993 and August 1999. Based on a 3-month preoperative smoking cessation, patients were classified as smokers, ex-smokers and non-smokers. Their postoperative pulmonary complications were compared and related to the duration of mechanical ventilation. RESULTS: Postoperative pulmonary complications were twice as common in smokers (29.5%) as non-smokers (13.6%) and ex-smokers (14.7%). Although smokers required a longer duration of mechanical ventilation, this was not statistically significant. Smokers had a higher rate of increase in postoperative pulmonary complications beyond 6 h of mechanical ventilation (P<0.002). CONCLUSION: Prolonged mechanical ventilation in active smokers undergoing cardiac surgery is associated with a significant increase in the respiratory morbidity. Surgical strategies that allow early extubation may improve the respiratory outcome in smokers.

Aortic rupture and false aneurysm formation following balloon angioplasty of coarctation in an adult: successful treatment by urgent surgery.

A 25-year-old man developed a false aneurysm as a result of acute disruption of the aortic wall immediately after successful balloon dilatation of his coarctation. He underwent emergency resection of the false aneurysm and end-to-end anastomosis of the descending aorta with an excellent result. The diagnosis and management of this complication are discussed.

Management of a mediastinal cyst causing hyperparathyroidism and tracheal obstruction.

A 78-year-old man with a history of parathyroidectomy presented with hyperparathyroidism and tracheal obstruction. After excision of the mediastinal parathyroid cyst, his symptoms were completely relieved. The diagnosis, investigations, and management are discussed.

False aneurysm of the right internal mammary artery.

False aneurysm of the internal mammary artery is an uncommon complication of median sternotomy. Clinical and radiological findings of 2 such cases are presented. At operative exploration neither was directly related to the presence of a sternal wire.

Right ventricular dynamic cardiomyoplasty: an experimental model.

The effectiveness of dynamic cardiomyoplasty as a means of haemodynamic support in heart failure remains controversial. We have undertaken a study of right ventricular dynamic cardiomyoplasty in sheep using intravenous propranolol to provoke heart failure. Muscle conditioning was performed with cardiomyostimulators following a previously established protocol. We performed multiple invasive measurements of haemodynamic parameters including arterial blood pressure, cardiac output, pulmonary artery capillary wedge pressure, right ventricular dp/dt and end diastolic pressures. These were performed before induction of heart failure, after induction of heart failure, and with pacing of the cardiomyoplasty flap in established heart failure. Our results confirm that we were able to establish significant heart failure and that subsequent pacing of the conditioned muscle flap was able to return cardiac output and right ventricular function to their pre-failure control levels.

Myocardial protective effects of lidoflazine during ischemia and reperfusion.

The myocardial protective effect of intravenous (i.v.) lidoflazine with potassium cardioplegia and hypothermia (28 degrees C) was investigated in 21 greyhounds. Animals were injected a single dose of cardioplegia (30 ml/kg body weight) and subjected to 120 minutes of ischaemia and 60 minutes of reperfusion. Ten dogs served as controls (Group C) and 11 dogs received i.v. lidoflazine (1.25 mg/kg b.w.) (Group L). Myocardial drill biopsies for the adenosine triphosphate (ATP) and the creatine phosphate (CP) levels were obtained. Hemodynamic measurements were made at intervals. In Group C, no dog could be weaned from bypass, whereas all 11 dogs in Group L came off bypass and maintained their circulation for 15 minutes. After a 120 minute ischemic period, the ATP and CP contents diminished significantly in both groups. Following reperfusion, the ATP level was 28% of the control level in Group C (p less than 0.005) and 38% in Group L (p less than 0.01). The CP levels showed an overshoot in both groups. There was no significant difference between the groups. In Group L animals, cardiac output (CO) and mean aortic pressure (MAP) were significantly reduced after bypass; from 5 +/- 1/min to 3.2 +/- 1, from 156 +/- 26 mmHg to 82 +/- 11 mmHg respectively (p less than 0.005). Left ventricular minute work (LVMW) also deteriorated markedly from 9.7 +/- 2 kg-m to 3.2 +/- 1 (p less than 0.005). The use of lidoflazine achieved considerable protection in terms of survival, but did not prevent the severe loss of high-energy phosphates in this experimental model.

Valve replacement in children under 14 years of age: a review of 22 years of experience.

From 1964 to 1986, a total of 18 valve replacement operations were performed in 15 children under 14 years of age, with 13% operative mortality. Eleven children had a mitral valve replacement, with 3 subsequently requiring reoperation. Twelve Starr-Edwards caged ball prostheses, 1 Björk-Shiley and 1 Carpentier-Edwards prosthesis were implanted in the mitral position, with 18% operative mortality. Three children underwent aortic valve replacement, 1 with a Björk-Shiley prosthesis and 2 with a Starr-Edwards. One patient had tricuspid valve replacement utilizing a Starr-Edwards valve. Thirteen patients had one or more cardiac operations prior to valve replacement. Two late deaths occurred 8 and 18 months, respectively, group, 1 from a cardiac arrhythmia and 1 from fulminating prosthetic valve endocarditis. There were no late deaths in other patients. There was one thromboembolic episode in the entire group. At follow-up, 10 patients were classified as New York Heart Association Functional Class I and 1 patient was Class III. Valve replacement in children can be carried out with low mortality and good long-term results using the Starr-Edwards caged ball prosthesis.

Repair of traumatic aortic transection: a management protocol and review of twenty-one patients.

Between 1970 and 1987, 21 patients at St. Vincent Hospital and Medical Center underwent surgery for repair of a transected descending aorta. Nineteen of the transections were a result of trauma secondary to motor vehicle accidents, 1 was secondary to compression injury of the chest, and 1 was the result of a fall. All of the patients had diagnostic chest X-rays and all but one X-ray showed a widened mediastinum. Aortography was carried out in 20 cases. Atrio-femoral bypass was used for all but 2 patients, who had femoro-femoral bypass. The mean cross-clamp time was 53 minutes. Interposition graft was used in 16 patients, an intraluminal graft in 1 patient, and primary repair was performed in 2 patients. Survival was 71%, with 4 of the 21 patients expiring in the operating room (2 before the repair could be undertaken), one patient expiring during a laparotomy 2 days after the aortic repair, and one patient expiring 4 days after the repair. Fifteen patients were discharged alive. Survival and patient care could be improved by careful diagnostic assessment and by following a protocol agreed upon by a team of surgeons.

Aortic valve replacement with the Starr-Edwards prosthesis: a comparison of the first and second decades of follow-up.

There are few prostheses in current use that allow 20-year follow-up. This report compares the rates of valve-related complications during the first and second decades following aortic valve replacement with the Silastic ball prosthesis. (table; see text) Valve-related complication rates with this prosthesis have been low overall. Performance characteristics of this valve have remained stable through the second decade of follow-up. These results should be used as the standard in the evaluation of long-term results with other more recently introduced mechanical and tissue valves.

Coronary artery compression caused by abscess formation in infective endocarditis.

Two cases are reported in which abscess formation during the course of infective endocarditis resulted in critical compression of the left coronary artery. In one case this resulted in unstable angina. Chest pain during infective endocarditis may be due to coronary artery compression by an abscess; successful treatment may require surgery, including a coronary artery bypass procedure.

Primary aortic malignant fibrous histiocytoma: a successfully treated case by surgical excision.

A man with a short history of retrosternal discomfort and weight loss was found to have a large malignant fibrous histiocytoma of the ascending aorta. The tumor was resected on partial cardiopulmonary bypass. We believe this is the only malignant fibrous histiocytoma of the ascending aorta reported and successfully treated in the literature.

Oral beta-blockade with hypothermic potassium cardioplegia in cardiac surgery: is there an additive protective effect?

The possible myocardial protective effect of oral propranolol in combination with potassium cardioplegia and hypothermia was investigated in 30 greyhounds, divided into 2 sub-groups, by determining the changes in myocardial ATP and CP levels, ultrastructural changes and the changes in hemodynamics after a 2-hour period of myocardial ischemia. In group 1, in animals with multiple doses of cardioplegia during the 2-hour ischemic period, preoperative treatment with propranolol did not have a significant myocardial protective effect. In group 2, in animals with a single dose of cardioplegia, during the 2-hour ischemic period, propranolol resulted in a trend of improved survival, although the myocardial ATP and CP levels were the same in both sub-groups. In addition, the multiple doses of cardioplegia in group 1 caused increased subcellular edema in the myocardium. This study suggests that oral propranolol treatment may provide additional myocardial protection during ischemic periods when used with potassium cardioplegia and hypothermia. The mechanism of this effect is not established, but could relate to reduced transmembrane calcium influx.

Symptomatic status and pattern of employment during a five-year period following myocardial revascularization for angina.

The employment status of 100 consecutive male patients between the ages of 30 and 60 years (mean, 49.5 years) operated on for angina and followed for a minimum of 5 years was analysed. There were no early and 4 late deaths. The probability of employment at 1 year was 90%, which was similar to that of a sample from the general population matched for age. This rate, however, showed steady, slow deterioration to 87.6% at 2 years, 82.1% at 3 years, 75.7% at 4 years, and 73.4+ at 5 years. Seventeen patients retired over the 5-year period. There was no correlation between the rate of employment and age (under or over 50) at operation, previous myocardial infarction, or number of grafts inserted.

Popliteal aneurysm: sinister harbinger of sudden catastrophe.

A series of twenty-eight aneurysms of the popliteal artery is reviewed. The cases were collected from the records of two large hospitals each with a unit with a special interest in vascular surgery. They are uncommon--only 1 popliteal aneurysm to every 17 aneurysms of the abdominal aorta--but one-third of our patients had both types of aneurysm present. The majority of patients had symptoms and 7 lost a leg as a direct result of thrombosis or rupture. The results of treatment were best when saphenous vein was used to replace an uncomplicated aneurysm and, since the behaviour of aneurysms is unpredictable, we conclude that this is the treatment of choice.

The surgical management of malignant tumours of the oesophagus and cardia: a review of the results in 292 patients treated over a 15-year period (1961--75).

Of 292 patients, excision of the tumour with replacement by stomach or jejunum was carried out in 216 in whom the lesion was considered operable on both technical and general grounds, intubation was performed in 45 and the remaining 31 were managed without operation. Of the 216 in whom resection was performed, only 20 per cent were free from local spread, lymph node involvement or secondary deposits at the time of operation. Hospital mortality was 18 per cent and did not significantly differ between one 5-year period and another. Survival at 1 year was 54 per cent, at 2 years 25 per cent and at 5 years 14 per cent. The average length of survival following intubation was 2.6 months and following non-operative management 2.8 months. The poor average survival of between 3.5 and 5 months obtained in those patients with secondary deposits at the time of resection suggests that resection is of questionable value in this group. There was a marked difference in survival following Roux loop procedures compared with upper partial gastrectomy for tumours of the lower third and cardia in patients without lymph node involvement or secondary deposits, strongly suggesting that upper partial gastrectomy, although a rather simpler and quicker operation, is not the operation of choice in these patients. On 31 December 1976, after a minimum follow-up of 1 year, there were only 22 patients still alive of the original 292 (7.5 per cent).