Effect of time of eCG administration on the fate of ovarian follicle in Holstein heifers.

The objective of this study was to investigate the effect of equine chorionic gonadotropin (eCG) on ovarian follicles at three stages of development (emergence, dominance and early static phases) during the first follicular wave (FFW) in Holstein heifers. Heifers (n=20) were randomly assigned into four experimental groups (n=5 in each group). Heifers received eCG (500 IU; Folligon®; Intervet, Holland; i.m) a) on the day of follicle emergence (day of ovulation; group 1), b) on the dominant phase (dominant follicle (DF): the first day in which follicle was observed at ≥10 mm; group 2, and c) on the early static phase (group 3) of the FFW. Control group heifers did not receive any treatment. Daily ultrasonography was conducted to monitor ovarian structure throughout estrous cycle. All treatment group heifers, regardless of the stage of follicle development, displayed follicle growth after eCG injection. Administration of eCG, in group 1, hastened DF detection and induced co-dominant follicles; whereas, in groups 2 and 3, it delayed DF regression, and increased cycle length compared to control. In all treatment group heifers, DF was present 84 h after eCG injection. Maximum diameter of corpus luteum was larger in eCG treated groups compared to control (P<0.05). In conclusion, depending on the time of eCG administration throughout the FFW (emergence, dominant and early static phases), co-dominancy, maintenance of DF, enhancement of follicle and corpus luteum growth and increase in estrous cycle length could be observed in Holstein heifers.

Ultrasonic characteristics of preovulatory follicle and ovulation in Caspian mares.

The Caspian breed of horses is believed to be the direct descendant of the earliest equine animals. Some special characteristics of Caspian horse differentiate this breed of horses from other breeds. In the current study the ultrasonically observed characteristics of a preovulatory dominant follicle and the lengths of estrus, diestrus as well as some related parameters were studied during 42 interovulatory intervals in 11 healthy Caspian mares. The preovulatory dominant follicle deviated from subordinate follicles and became the largest follicle in the ovaries at Day -8.7 +/- 0.53 (Day 0=ovulation). Every mare was a single ovulator with ovulations more frequent from the left ovary than from the right (65% versus 35%). Mean length of estrus, diestrus, and interovulatory interval were 8.3 +/- 0.86, 13.8 +/- 0.59, and 22.1 +/- 0.40 days, respectively. The time interval from ovulation until the time in which the mares were no longer in estrus was 1.9 +/- 0.42 days.

Right atrial thrombus in a patient with stage IV carcinoma of the lung: is the surgical treatment the correct choice?

Thrombus in the right atrium or ventricle is rare and carries a mortality rate of 40%. Death frequently occurs when the thrombus moves toward the pulmonary arteries. Emergent treatment is therefore required. However there is no clear consensus regarding therapeutic management. We present here a patient with right atrial thrombus who underwent surgical exploration of the right atrium and successful thrombectomy.

Pleural space irrigation and modified Clagett procedure for the treatment of early postpneumonectomy empyema.

OBJECTIVE: The incidence of postpneumonectomy empyema is 5% to 10%. Approximately half of postpneumonectomy empyemas occur within 4 weeks of pneumonectomy. A bronchopleural fistula is found in more than 80% of the patients. The classic treatment of postpneumonectomy empyema includes parenteral antibiotics, drainage of the pleural space, removal of necrotic tissue, and open pleural packing for many weeks followed by obliteration of the empyema space with antibiotic fluid or muscle. This approach results in prolonged hospitalization, repeated operations, and significant morbidity. As a possible means of decreasing morbidity with the classic treatment of postpneumonectomy empyema, we studied the use of pleural space irrigation in these patients. METHOD: In a 5-year period, we treated 22 patients with early postpneumonectomy empyema. All patients had a bronchopleural fistula. All patients underwent emergency drainage of the pleural space followed by thoracotomy, debridement of necrotic tissue, closure of the bronchial stump with absorbable monofilament suture, and pleural space irrigation. After a negative Gram stain from the pleural fluid, the pleural space was filled with 2 L of debridement antibiotic solution (DAB solution) (gentamicin 80 mg/L, neomycin 500 mg/L, and polymyxin B 100 mg/L), and the irrigation and drainage catheters were removed. RESULTS: Twenty patients had negative Gram stains on day 9, and 2 patients had a negative Gram stain on day 16. The mean duration of hospitalization was 12.9 +/- 3. 4 days. There was no recurrence of empyema or a bronchopleural fistula. CONCLUSIONS: Pleural space irrigation followed by obliteration of the pleural space with an antibiotic solution required one surgical procedure and resulted in significantly shorter hospitalization and decreased morbidity in patients with early postpneumonectomy empyema.

A comparison of the reliability of two techniques of left double-lumen tube bronchial cuff inflation in producing water-tight seal of the left mainstem bronchus.

UNLABELLED: A double-lumen endobronchial tube (DLT) bronchial cuff inflation technique that reliably ensures effective water-tight isolation of the two lungs has not been determined. In this study, 20 patients undergoing thoracic surgery requiring a left DLT had the bronchial cuff of the DLT inflated by one of two techniques. In Group 1, the cuff was inflated to produce an air-tight seal of the left bronchus using the underwater seal technique. In Group 2, the cuff was inflated to a pressure of 25 cm H2O. After bronchial cuff inflation in both groups, water-tight bronchial seal was tested by instilling 2 mL of 0.01% methylene blue (MB) above the bronchial cuff of the DLT. Fifteen minutes later, fiberoptic bronchoscopy was performed via the bronchial lumen of the DLT to determine whether MB had seeped past the bronchial cuff. Cuff volume was 0.75+/-0.64 and 0.76+/-0.46 mL, cuff pressure was 30.1+/-27.0 and 25.0+/-0.0 cm H2O (mean+/-SD), and MB was positively identified in two and five patients in Groups 1 and 2, respectively. The difference in cuff volume and pressure and the higher MB seepage in Group 2 compared with Group 1 was not statistically significant. In both groups, MB seepage occurred only when the bronchial cuff volume was <1 mL and when the patients were positioned in the left lateral decubitus position. These findings suggest that the risk of aspiration is greatest when the DLT is positioned in the dependent lung and when the bronchial cuff volume is <1 mL. IMPLICATIONS: Water-tight sealing of the left bronchus by DLT bronchial cuff was tested after cuff inflation using two different techniques. Neither air-tight bronchial seal nor cuff pressure of 25 cm H2O guaranteed protection against aspiration. The risk of aspiration was greatest when the DLT was positioned in the dependent lung and when the bronchial cuff volume was < 1 mL.

Spinal cord protection during surgical procedures on the descending thoracic and thoracoabdominal aorta: a critical overview.

During the past three decades, significant advances have been made in the surgical treatment of the diseases affecting the aorta. Despite these important advances, paraplegia remains a devastating complication of the surgical procedures on the thoracic and thoracoabdominal aorta. Paraparesis and paraplegia occur as a direct result of the interruption of blood flow to the spinal cord during the surgical procedures. A number of techniques have been advocated for the prevention of spinal cord ischemic injury. This article critically reviews our current understanding of the extent of this problem, the mechanism of injury, and the methods that have been devised to reduce the frequency of paraplegia following surgical procedures on the descending aorta.

Surgical management of endocarditis-induced aorto-atrial and aorto-ventricular fistula: a new technique.

Early onset aortic prosthetic valve endocarditis with annular extension of the infectious process remains a highly lethal disease. Destruction of the annular tissue requires complex techniques for repair. The most challenging situation is associated with destruction and fistula formation at the left fibrous trigone. We report a technique using the anterior mitral leaflet to repair an aorto-atrial and aorto-ventricular fistula. This technique places autologous tissue from the anterior leaflet of the mitral valve against the infected area, and may decrease the risk of reinfection.

Tension pneumothorax precluding laparoscopic repair of diaphragmatic hernia.

Pneumothorax can result from laparoscopic procedures in the abdomen. Usually, pneumothoraxes are mild and asymptomatic and do not require conversion to an open procedure. We report a case of tension pneumothorax that developed during the course of a laparoscopic repair of a diaphragmatic hernia. In this patient, the tension pneumothorax did not respond to conventional means of therapy and required conversion to a laparotomy. A large diaphragmatic hernia with communication between the peritoneal and pleural cavities may be a contraindication to minimally invasive laparoscopic procedures.

Video-laparoscopic reduction of an intrathoracic stomach.

A paraesophageal hiatal hernia is caused by a defect in the anterolateral aspect of the diaphragmatic esophageal hiatus. Most commonly, the stomach migrates into the hernia sac. Although most patients are asymptomatic, repair is advised at the time of the diagnosis because of the high morbidity and mortality associated with surgery for the complications of paraesophageal hiatal hernias. However, because of the morbidity associated with conventional surgical techniques, there has been great reluctance to subject an asymptomatic patient to surgical repair. We report a minimally invasive technique for the reduction of a paraesophageal hiatal hernia and repair of the diaphragmatic hiatal defect. Video laparoscopy, with its attendant low morbidity, may be the ideal technique for the repair of paraesophageal hiatal hernias.

Thoracoscopic plication of the diaphragm.

Plication of the diaphragm in symptomatic patients with phrenic nerve paralysis provides excellent relief of excertional dyspnea and significantly increases arterial oxygen tension, and all lung volumes except residual volume. We report diaphragmatic plication using the minimally invasive technique of VATS. This procedure provides excellent relief of symptoms with minimal morbidity and short hospitalization.

Recurrent bronchogenic pseudocyst 24 years after incomplete excision. Report of a case.

Bronchogenic cysts (BCs) are uncommon congenital anomalies. Due to the inherent complications, the mere presence of a BC should warrant surgical therapy. Partial excision of these structures leads to recurrence. Complete surgical excision using a thoracotomy or video-assisted thoracic surgery is the goal. We report a case of recurrent bronchogenic pseudocyst 24 years after initial excision. This case supports the argument for complete surgical excision of BCs at the time of diagnosis.

Video-assisted thoracoscopic resection of intercostal neurofibroma.

BACKGROUND Video-assisted thoracoscopy (VAT) is being increasingly utilized by thoracic surgeons as an alternative to thoracotomy for several thoracic disorders. Neuroendoscopy is an exciting addition to the neurosurgical armamentarium. These procedures are attractive alternatives in the era of minimally invasive surgery and cost containment, while providing the highest quality medical care to patients. METHODS We report the application of this technology in a patient presenting with intractable thoracic radicular pain secondary to an intercostal neurofibroma. Complete excision of the intercostal neurofibroma was performed utilizing VAT. RESULTS The patient reported good relief of her preoperative thoracic radicular pain. She was ready for discharge from the hospital within 72 hours of surgery. CONCLUSIONS With the advent of improved instrumentation, video-assisted thoracoscopy offers a safe alternative to thoracotomy and the potential benefits of less postoperative discomfort and shorter hospital stays. The potential neurosurgical applications of VAT should not be overlooked.

Thoracoscopic excision of a peripheral corticotropin-secreting pulmonary carcinoid tumor.

Bronchial carcinoid tumors are rare neuroendocrine neoplasms that arise from the Kulchitsky cells of the bronchial epithelium. These tumors can manifest as central carcinoid tumors, pulmonary carcinoid tumorlets, or peripheral carcinoid tumors. Occasionally, the peripheral carcinoid tumors produce corticotropin and result in Cushing's syndrome. Herein we report the first case of Cushing's syndrome associated with a peripheral pulmonary carcinoid tumor that was excised by video-assisted thoracoscopy. After excision, the patient had complete remission. Video-assisted thoracoscopy may be ideal for resecting a peripheral pulmonary carcinoid, especially in patients with debilitation but no evidence of metastasis.

Multiple myocardial hamartomas causing ventricular tachycardia in young children: combined surgical modification and medical treatment.

OBJECTIVE: To describe two cases of incessant ventricular tachycardia caused by multiple myocardial hamartomas. MATERIAL AND METHODS: Two infants, 13 and 14 months old, who had had multiple episodes of symptomatic tachycardia were referred to our institution. Incessant ventricular tachycardia was diagnosed. Initially, the patients received pharmacologic therapy. The recurrent tachycardia resulted in notable hemodynamic instability. No structural abnormalities were detected on the echocardiograms. In one patient, an electrophysiologic study revealed that the site of ventricular ectopic beats was in the anterolateral wall of the left ventricle, midway between the apex and the base. In the other patient, a preoperative electrophysiologic study was not undertaken because of the inability to obtain central venous access. RESULTS: Diffuse hamartomas were found throughout the ventricular myocardium in both patients. Surgical resection and cryoablation of the lesions in combination with medical therapy helped control the tachyarrhythmia. At 7 and 17 months postoperatively, the patients were in normal sinus rhythm and were receiving medication. CONCLUSION: In young children who have incessant ventricular tachycardia but no lesion evident on echocardiography, angiography, or other imaging modalities, a myocardial tumor should be suspected, and pharmacologic therapy should be instituted. If the medical regimen fails, surgical intervention should be undertaken, directed at areas localized by inspection and by preoperative and intraoperative electrophysiologic studies.

Modified Fontan operation in the presence of anomalies of systemic and pulmonary venous connection.

BACKGROUND: The purpose of this report is to outline technical maneuvers dictated by anomalies of systemic and/or pulmonary venous connection in the performance of the Fontan procedure. METHODS AND RESULTS: Between 1975 and 1990, 104 patients (60 male, 44 female) with anomalies of systemic and/or pulmonary venous connection underwent a modified Fontan procedure at the Mayo Clinic. Mean age was 9.7 +/- 5.7 years. Isolated anomalies of the systemic venous connection were identified in 46 patients, isolated anomalous pulmonary venous connections in 4, and a combination of the two in 54. Previous palliative operations had been performed in 93 patients. Surgical repair was accomplished by atrial septation or placement of an intra-atrial conduit combined with cavopulmonary anastomosis if required. Survival by Kaplan-Meier, including operative mortality, was 55.7% at 10.3 years, not significantly different from the overall survival of the Fontan population. By the proportional hazards general linear model procedure, insufficiency of the systemic atrioventricular valve, preoperative mean pulmonary pressure greater than 15 mm Hg, and pulmonary artery resistance index greater than 4 U.m2 were associated with higher mortality. Five patients required reoperation for pulmonary venous obstruction (1 patient), revision of the atrial baffle (1 patient), revision of the intra-atrial conduit (2 patients), and replacement of the systemic atrioventricular valve (1 patient). CONCLUSIONS: We conclude that the modified Fontan operation can be successfully performed in this subset of patients, with long-term results comparable to those obtained in patients with normal systemic and pulmonary venous connection.

Early thrombotic stenosis of aortic bioprosthetic valves: report of two cases.

Thrombotic stenosis of a Carpentier-Edwards porcine bioprosthesis occurred in two patients within 3 months after aortic valve replacement. Both patients underwent successful replacement of the aortic prosthesis. Although previously reported, this complication of aortic porcine bioprostheses is uncommon.

Use of the internal mammary artery for myocardial revascularization in a patient with radiation-induced coronary artery disease.

A 9-year-old boy with clinical stage IIA Hodgkin's disease underwent radiotherapy to the neck and mediastinum. Twenty-two years later, he sought medical attention because of angina pectoris. Cardiac catheterization revealed proximally located high-grade stenoses of the left main, left anterior descending, circumflex, and right coronary arteries. He underwent coronary artery bypass grafting with use of the left internal mammary artery to the left anterior descending coronary artery and reversed saphenous vein grafts to the circumflex and right coronary arteries. The postoperative course was uncomplicated. Previous radiotherapy to the mediastinum should be considered a risk factor for the development of premature coronary artery disease. Surgical revascularization is the preferred method of management. A combination of an internal mammary artery graft and a saphenous vein graft should be used in young patients.

The effect of superoxide dismutase and catalase on the extended preservation of the ex vivo heart for transplantation.

The applicability of heart transplantation remains limited in part by the inability to preserve the excised heart for long periods of time. Free radical scavengers have been shown to protect the anoxic myocardium by preventing damage to the cell membrane and may, therefore, be effective in extending successful preservation of donor hearts. We perfused 10 sheep hearts for 8 hours in an ex vivo perfusion system. The effect of superoxide dismutase combined with catalase, 60,000 units/L, was studied in five sheep, and five received placebo. Control determinations and determinations after 8 hours of preservation were obtained with the heart perfused with autologous blood at 37 degrees C at an aortic perfusion pressure of 60 mm Hg and flow of 180 to 200 ml/min. After control readings, the hearts were arrested and perfused with a cold (6 degrees to 8 degrees C) oxygenated buffered crystalloid solution with or without superoxide dismutase and catalase at a perfusion pressure of 30 cm H2O for 8 hours. Left and right ventricular compliance was measured sequentially with separate intraventricular balloons. After 8 hours of ex vivo preservation, hearts receiving superoxide dismutase and catalase had significantly better left and right ventricular performance, higher myocardial oxygen consumption, and lower lactate production than the control group. The hearts preserved with superoxide dismutase and catalase showed significantly better left and right ventricular compliance, much less increase in heart weight, and no change in the diastolic pressures. The results suggest that superoxide dismutase combined with catalase may be effective in extending ex vivo preservation of hearts for cardiac transplantation.

Effects of diltiazem cardioplegia on global function, segmental contractility, and the area of necrosis after acute coronary artery occlusion and surgical reperfusion.

We investigated the effects of diltiazem cardioplegia on myocardial function and infarct size in the region of the left anterior descending artery after acute occlusion and reperfusion during cardiopulmonary bypass. Sheep (30 kg) were subjected to 1 hour of regional myocardial ischemia by occlusion of the left anterior descending artery and assigned to a control (n = 8) or experimental group (n = 5). Control animals were placed on cardiopulmonary bypass and the heart arrested with potassium cardioplegia. The left anterior descending artery was released and two additional doses of 100 ml of cardioplegic solution were infused during the total cross-clamp time of 30 minutes. The animals were then weaned from bypass after 1 hour and beating, working reperfusion maintained for an additional 4 hours. The experimental group followed the same protocol except that the cardioplegic solution contained diltiazem (1.4 mg/L). Segmental myocardial function was determined by pairs of ultrasonic crystals in the area at risk, control segment, and minor axis. Global contractility was determined from maximum derivative of left ventricular pressure and cardiac output. The area at risk was determined by injecting monastral blue dye into the left atrium with the left anterior descending artery briefly reoccluded, and the area of necrosis was determined by measuring with a planimeter non-triphenyltetrazolium chloride stained areas in the sectioned left ventricle. After 5 hours of reperfusion, not only did the diltiazem group demonstrate better global contractility as defined by the derivative of left ventricular pressure (1853 +/- 292 versus 979 +/- 191, p = 0.05) but, in addition, the systolic shortening in the ischemic area improved significantly when compared with the control group (9.4 +/- 4 versus 2.13 +/- 0.77, p = 0.05). The group receiving diltiazem cardioplegia had an area of necrosis to area at risk ratio of 31.4% +/- 3%, which was significantly better than this ratio in the control group of 60.75% +/- 7% (p = 0.01). Diltiazem cardioplegia results in improved global and segmental contractility and limits the infarct size after occlusion of the left anterior descending artery and surgical reperfusion.