[Clinical analysis of hepatic perivascular epithelioid cell neoplasm: a report of eleven cases]

Objective: To investigate the clinical features, diagnosis and therapy of hepatic perivascular epithelioid neoplasms (PEComa). Methods: The clinical data of eleven patients with hepatic PEComa who received surgical treatment at Shengjing Hospital Affiliated to China Medical University from April 2012 to October 2017 were collected. The clinical manifestations, imaging features, diagnostic and therapeutic strategies, pathologic features, prognosis were analyzed. Results: The patients aged from 35 to 55 years (mean: 47 years , 3 males and 8 females). Two patients had epigastric pain, the others rarely had any clinical symptom. Hepatitis C virus (HCV) infection was present in one patient 9.09%(1/11), the rate of correct diagnosis by imageological examination before operation was only 9.09%(1/11). All patients received a surgical resection, the final diagnosis of hepatic PEComa was made with pathology and immunohistochemistry. The antibodies used for immunohistochemistry varied from patient to patient. The positive rates of Melan A, HMB45, smooth muscle actin and S-100 were 100%(10/10), 90%(9/10), 77.8%(7/9)and 33.3%(3/9) respectively, the Ki-67 positive index was 1%-10%. One patient died after surgery because of hemorrhage, other ten patients received long-term follow-up(5-71 months), and no recurrence or metastasis was observed. Conclusion: Hepatic PEComa is a rare mesenchymal neoplasm which expresses both melanocytic and myogenic markers. Middle aged females are susceptive to hepatic PEComa, and patients rarely have any specific clinical presentation. It's difficult to make a correct diagnosis before operation. The diagnosis finally depends on the pathological examination. Surgical resection and close follow-up are the principal methods for the management of hepatic PEComa.

[Inflammatory myofibroblastic tumor of the hepatobiliary pancreatic system: report of three cases and literature review]

Objective: To improve the understanding, diagnosis and treatment of inflammatory myofibroblastic tumor (IMT) of the hepatobiliary pancreatic system through the cases review. Methods: The clinical data of three cases of pathologically-proved IMT of the hepatobiliary pancreatic system was reported and relevant literatures were reviewed. Results: Among three cases of IMT discussed, there consisted of a case of liver, a case of gallbladder and a case of pancreas. The clinical manifestations were nonspecific, and the preoperative diagnosis was difficult. All the patients with suspected malignant tumors underwent surgical treatment. The prognosis was good, with no recurrence. Conclusion: IMT is a benign tumor and is rare in hepatobiliary pancreatic system. The clinical manifestations are not typical and the imaging examinations are not specific. Its diagnosis depends on pathology. Surgery is an effective treatment. IMT has a tendency of recurrence, and its postoperative follow-up is of great significance.

[Clinical study on the relationship between pancreatic fistula and the degree of pancreatic fibrosis after pancreatic and duodenal resection]

Objective: To explore the risk factors of pancreatic fistula after pancreatoduodenectomy and its relationship with pancreatic fibrosis. Methods: Retrospective analysis was made including 408 patients who underwent pancreaticoduodenectomy from January 2013 to December 2015 in Department of Hepatobiliary Surgery of the First Affiliated Hospital of Third Military Medical University. There were 274 males and females, aging from 14 to 82 years with an average age of 54.6 years. Postoperative pathological diagnosis: 285 cases with pancreatic ductal adenocarcinoma, 81 cases with gastrointestinal tumors, 13 cases with neuroendocrine tumors, 16 cases with inflammatory changes, 8 cases with pancreatic papillary tumors, 4 cases with serous cystadenoma, 1 case with retroperitoneal liposarcoma.Univariate analysis using pearson's χ(2) test, multivariate analysis using binary Logistic regression analysis, correlation analysis using Spearman rank correlation analysis and the predictive value of pancreatic fibrosis in pancreatic fistula after pancreaticoduodenectomy was assessed using the area under the receiver operating characteristic(ROC) curve. Results: There were 123 cases (30.1%) with postoperative pancreatic fistula among 408 patients. Univariate analysis showed that body mass index(BMI)(P=0.005), preoperative gamma-glutamyltranspeptidase content(P=0.046), pancreatic duct diameter(P=0.001), CT value of pancreatic tissue(P=0.049), operation time(P=0.037), pancreatic stiffness (intraoperative judgment)(P=0.001) and percentage of pancreatic fibrosis(P=0.034) were the prognostic factors of pancreatic fistula. Multivariate analysis showed that BMI≥25 kg/m(2), pancreatic duct diameter ≤3 mm, pancreatic tissue CT value <40 Hu, pancreatic hardness (intraoperative judgments) for the soft and pancreatic lobular fibrosis percentage ≤25% of postoperative pancreatic fistula occurrence of high-risk factor(P<0.05). Pancreatic fistula's CT value and percentage of pancreatic fibrosis were significantly lower than non-pancreatic fistula group, the difference was statistically significant(P<0.05). There were significant differences in CT value and pancreatic lobular fibrosis among different grades of pancreatic fistulae(P<0.05). Pancreatic fistula severity was negatively correlated with the CT value of pancreatic body and the percentage of fibrosis of the pancreas(P=0.005, 0.019), and there was a significant correlation between CT value of pancreatic body and the percentage of fibrosis of the pancreas(r=0.699, P=0.028). The areas under the ROC curve of percentage of pancreatic fibrosis and CT value of the pancreatic body were 0.745 and 0.714, respectively. Both of them were moderate predictive value for pancreatic fistula after pancreaticoduodenectomy. Conclusions: The degree of pancreatic fibrosis is a prognostic factor for pancreatic texture and pancreatic fistula after pancreaticoduodenectomy. CT value of pancreatic body can be used as a quantitative index of pancreatic fibrosis, and predict the prognostic of pancreatic fistula after pancreaticoduodenectomy.

Stroke volume variation derived by arterial pulse contour analysis is a good indicator for preload estimation during liver transplantation

BACKGROUND

Accurate determination of preload during liver transplantation is essential. Continuous right ventricular end diastolic volume index (RVEDVI) has been shown to be a better preload indicator during liver transplantation than the filling pressures. However, recent evidence has shown that dynamic variables, in this case stroke volume variation (SVV), are also good indicators of preload responsiveness. In this study, we evaluated the correlation between SVV, which we derived from arterial pulse contour analysis and RVEDVI.

METHODS

In this study, we looked for possible relationships between SVV obtained through FloTrac/Vigileo monitor, central venous pressure (CVP), pulmonary arterial occlusion pressure (PAOP), and RVEDVI in 30 patients undergoing liver transplantation. Measurements were taken at 11 defined points during different phases across liver transplantation. Each set of measurement was taken during a steady state, which means at least 15 minutes elpased after any changes occured in either the infusion rate of catecholamines or ventilator settings. Pearson's test was used for correlation estimation.

RESULTS

There was a statistically significant (P<.01) relationship between SVV and RVEDVI with a correlation coefficient of -0.87. The correlations between CVP (r=0.42), PAOA (r=0.46), and RVEDVI were less strong.

CONCLUSION

We conclude that SVV is a good indicator for preload estimation during liver transplantation. A higher SVV value is associated with a more hypovolemic fluid status.

Anesthetic management of a patient with relapsing polychondritis--a case report

Relapsing polychondritis is a rare multisystem disorder of uncertain etiology. It is characterized by recurrent and progressive destruction of both elastic and hyaline cartilages as well as connective tissue. Respiratory tract involvement is associated with high mortality and morbidity. General anesthesia may be required in these patients for tracheostomy, bronchoscopy, nasal reconstruction, aortic valve replacement, and recent tracheobronchial stenting which they usually sustain. Tracheostomy was once the most likely surgical procedure in relapsing polychondritis. However, this procedure is only effective in patients with upper subglottic involvement. In cases of extensive tracheobronchial involvement, tracheostomy is ineffective because the distant tracheal collapse below the tracheostomy is still unresolved. We would like to report a case of relapsing polychondritis with tracheobronchial involvement, who underwent an emergent tracheostomy. Tracheostomy with continuous positive airway pressure (CPAP) effectively improved her airway collapse. Herein, we also discuss the anesthetic management after review of the current literature.

Diagnosis of progressive compression of the aortic true lumen with intraoperative transesophageal echocardiography during repair of dissection of thoracic aorta--a case report

We report an incident of progressive compression of the true lumen of aorta which happened immediately after cardiopulmonary bypass (CPB) and was diagnosed with intraoperative transesophageal echocardiography (TEE) in a patient undergoing an emergent repair of type A aortic dissection under femoral perfusion. During the CPB period, intraoperative TEE revealed gradual expansion of the false lumen which nearly obstructed the true lumen of the dissected aorta. The possible mechanism was related with distension of the false lumen by a dominant flow from retrograde femoral perfusion of CPB. With the application of intraoperative TEE, we could easily detect the hemodynamic changes of thoracic aorta and find the real causes so as to solve the perfusion abnormalities.

Evaluation of learning effectiveness in endotracheal intubation by the use of a laryngoscope in combination with a flexible fiberoptic bronchoscope

BACKGROUND

Accidental esophageal intubation may cause lethal complications when undetected. We developed a laryngoscope, which utilizes a laryngoscope blade incorporating with a flexible fiberoptic bronchoscope for teaching new learners. We compared two teaching methods, i.e. the traditional method and the new method we contemplated, for teaching new interns.

METHODS

We selected new interns as our study group. Everyone had six turns, four of which for the traditional method (T) and two of which for the new method (N), to perform the procedure under the guidance of a teaching supervisor. The interns were assigned randomly to one of three groups. Group 1 used the series of TTTTNN; group 2, TTNNTT; and group 3, NNTTTT. We used success or failure of intubation as the result of our evaluation. Statistical analyses were performed by chi-square test.

RESULTS

84 interns performed 504 endotracheal intubation trials during a period of 4 years. There was a 91.7% success rate with the new method and a 78.9% success rate with the traditional technique (P < 0.05). The group to which the new method was initially taught achieved the highest success rate of intubation and the greatest feeling of satisfaction according to a self-evaluation record. Of the failed intubations, 82.4% were due to performing the procedure in more than one minute, 15.3% due to esophageal intubation and the remaining 2.3% due to contact bleeding of teeth or oral trauma.

CONCLUSIONS

By using the new teaching method, the supervisor could easily teach and assess the success of the new learners. Besides, esophageal intubation could be reduced to a minimum with subsequent increase of success rate.

The use of multiplane transesophageal echocardiography to evaluate residual patent ductus arteriosus during video-assisted thoracoscopy in adults

BACKGROUND

Video-assisted thoracoscopic surgery (VATS) has emerged as an innovative and popular procedure for interruption of patent ductus arteriosus (PDA), while intraoperative transesophageal echocardiography (TEE) has proven to be an effective monitor in the evaluation of residual patency. Previous reports on the adequacy of surgical interruption of PDA under VATS and TEE are available for pediatric patients, but only limited information is available for adults with PDA. MATEIALS AND METHODS: Between August 1995 and October 1997, we monitored 35 adult patients undergoing PDA interruption via VATS with Hewlett-Packard color Doppler multiplane TEE throughout the procedure. The average PDA diameter was 10.2 +/- 1.8 mm. All the PDA were completely ligated.

RESULTS

Thirty-two patients showed no ductal flow after double ligation. In the other three patients, residual flow was detected intraoperatively after double ligation, but it was quickly abolished by the third ligation. One patient showed faint ductal flow by transthoracic echocardiography at postoperative follow-up, but no reintervention was needed.

CONCLUSIONS

Our study showed that, with the refinement of adult PDA interruption via VATS, intraoperative multiplane TEE provides higher resolution for direct evaluation of the entire course of PDA ligation without interrupting the surgical procedure and minimizes the incidence of complications.

Minimally invasive cardiac surgery for intracardiac congenital lesions

OBJECTIVE

Minimally invasive cardiac surgery has recently been applied to the correction of intracardiac lesions. This report reviews our experience of minimally invasive cardiac surgery in 119 patients with intracardiac congenital lesions.

METHODS

From October 1995 to April 1997, 119 patients (48 male and 71 female, aged 0.9-65 years old, 18.5+/-17.8) received elective minimally invasive cardiac surgery at Chang Gung Memorial Hospital, Taipei, Taiwan for repair of atrial septal defect (96 patients) or ventricular septal defect (23 patients). The operations were performed through right submammary incision (ASD) or left parasternal minithoracotomy (VSD), under femoro-femoral or femoro-atrial cardiopulmonary bypass with fibrillatory arrest.

RESULTS

All of the defects were repaired successfully. The bypass time was 25-125 min (46+/-18). The operation time was 1.5-5.2 h (2.8+/-0.8). The postoperative course was uneventful in all patients. Follow-up (1.0-18.2 months, mean 7.3) was complete, with no late deaths or residual shunt. All patients were found to be in NYHA functional class I or II.

CONCLUSION

Our experience demonstrate that minimally invasive cardiac surgery is a technically feasible, safe, and effective procedure in surgical correction of selective simple intracardiac congenital lesions, yielding good short-term results.

Video-assisted cardiac surgery for intracardiac tumors

OBJECTIVE

To present our experience in surgical excision of intracardiac tumors in three patients using video-assisted cardiac surgical techniques.

METHODS

Three patients received emergency video-assisted cardiac surgery for excision of right atrial or left atrial tumors. These surgeries were performed through right anterior submammary minithoracotomies and guided by video-assisted endoscopic techniques by projected images on a video monitor while under femoro-femoral cardiopulmonary bypass. The myocardium was protected by continuous coronary perfusion with fibrillatory arrest. Conventional instruments were used.

RESULTS

All but one of the tumors were excised completely. The bypass time was 88-148 min. The operation time was 3.5-4.4 h. There were no operative deaths. Pathological examination of the tumors showed left atrial myxoma, metastatic left atrial choriocarcinoma, and right atrial lymphoma. One patient died from non-cardiac origin 5 weeks after discharge. Follow-up was completed with the two survivors. Transthoracic echocardiographic examination showed good ventricular function without any residual tumors. They were both in New York Heart Association functional class I or II. They were satisfied with the cosmetic healing of their incisions.

CONCLUSION

Video-assisted cardiac surgery is technically feasible and can be performed in surgical excision of intracardiac tumors.

Totally minimally invasive cardiac surgery for coronary artery disease

OBJECTIVE

We report our experience using minimally invasive techniques both to perform coronary artery bypass and harvesting of saphenous vein grafts in 25 patients with left main or triple vessels disease.

METHODS

From March 1997 to June 1997, 25 patients received elective coronary artery bypass grafting using minimally invasive surgical techniques for left main or triple vessels disease. Saphenous vein grafts were harvested using minimally invasive techniques under direct vision. The coronary artery bypass grafting was performed through a limited left anterior parasternal minithoracotomy under femoro-femoral or aorto-atrial cardiopulmonary bypass. The myocardium was protected by antegrade infusion of cold blood cardioplegic solution while the aorta was cross-clamped.

RESULTS

Three to four distal anastomoses were performed with the saphenous vein graft and the left internal thoracic arterial graft. The aortic cross-clamp time was 60-135 min. The duration of cardiopulmonary bypass was 89-172 min. The postoperative course was uneventful for all patients. All patients were found to be in New York Heart Association functional class I or II on follow-up from 3-7 months after surgery.

CONCLUSIONS

Minimally invasive coronary artery surgery is technically feasible and can be performed in left main or triple vessel disease safely and effectively for complete revascularization.

Video-assisted minimal access in excision of left atrial myxoma

BACKGROUND

Minimal access surgery with video-assisted endoscopy has been applied to the correction of intracardiac lesions. We report our experience using this technique in surgical excision of left atrial myxoma in 3 patients.

METHODS

From November 1995 to March 1997, 3 female patients, ages 45 to 80 years (mean, 62.7 years), received emergency operations for excision of left atrial myxoma. These operations were performed through a right anterior submammary minithoracotomy or right parasternal incision with the assistance of endoscopy during femoro-femoral cardiopulmonary bypass. The myocardium was protected by continuous coronary perfusion with fibrillatory arrest or cardioplegic arrest with aortic cross-clamping.

RESULTS

All the tumors were excised completely through the right atrial approach. The bypass time was 92 to 148 minutes (mean, 111 minutes). The operation time was 3.2 to 4.4 hours (mean, 3.7 hours). There were no hospital deaths. Follow-up, which ranged from 6 to 19 months (mean, 10.5 months), was complete in all patients. Transthoracic echocardiographic examination showed good ventricular function without any residual tumors. Patients were found to be in New York Heart Association functional class I or II. They were satisfied with the good cosmetic healing of the incision.

CONCLUSIONS

Our experience demonstrates that minimal access surgery is a technically feasible, safe, and effective procedure in surgical excision of left atrial myxoma.

Airway compression by a biplane pediatric transesophageal echocardiography probe: case report

Transesophageal echocardiography (TEE) has been extensively used in cardiac surgery to assess cardiac function and anatomical relationships in both adults and children. Newer monitoring devices, despite being labeled "noninvasive", often present significant risks. Physicians should be cautious with the use of TEE in infants and small children, recognizing that oversized probes may inadvertently compress vital structures, resulting in airway or vascular compromise. If severe compression of the airway or vascular structures occurs, TEE monitoring may need to be discontinued. Although technological progress has yielded smaller ultrasonic probes, the TEE probe is significantly larger than most other devices placed in the esophagus. We present in this report a case of airway compression using a small-sized biplane pediatric TEE probe in a child undergoing Blalock-Taussig shunt surgery. Pediatric patients may be more at risk for airway obstruction because of the over-size of the probe-distended esophagus in relation to adjacent airway structures.

Surgical closure of atrial septal defect. Minimally invasive cardiac surgery or median sternotomy?

BACKGROUND

Closure of ostium secundum atrial septal defect (ASD) vis median sternotomy (MS) is a simple procedure for most cardiac surgeons. Minimally invasive cardiac surgery (MICS) has recently been applied in the management of intracardiac lesions.

METHODS

We report our experience in surgical closure of isolated ASD via MICS in 60 patients and via MS in 58 patients. There was no difference between these two groups in gender, age, body weight, ratio of systemic to pulmonary blood flow, and pulmonary arterial pressure.

RESULTS

The duration of cardiopulmonary bypass was significantly longer in the MICS group than in the MS group [27 to 126 min (42 +/- 12) and 14 to 158 min (27 +/- 11), respectively; (p < 0.001]. However, the length of incision, incidence of temporary pacemaker wire insertion rate, duration of endotracheal intubation, timing of oral intake, postoperative day drainage amount, incidence of parenteral analgesic injection, postoperative length of stay, and return to normal activity interval were significant shorter and lower in patients of the MICS group than in those of the MS group. All the patients recovered rapidly from the surgery. Follow-up was complete in all patients, with no late complications and no residual shunt.

CONCLUSION

Our results suggest that MICS is a good option for surgical closure of ASD.

Power spectral analysis of arterial blood pressure after spinal anesthesia

BACKGROUND

The continuous, on-line and real-time analysis of the power spectrum (CORAPS) of systemic arterial pressure (SAP) and heart rate (HR) signals is one of the current progresses in the development of non-invasive indexes for autonomic nervous system. It might be a useful clinical tool to monitor the progress of preganglionic block of sympathetic nervous system and the homeostatsis of cardiac neuroregulation after spinal anesthesia. The purpose of this study is to examine the relationship between the hypotensive response and the changes of components in CORAPS throughout the course of spinal anesthesia.

METHODS

In 10 ASA class I-II patients (aged from 17 to 75 years) scheduled for elective surgery, we analyzed the changes of spectrum of systemic arterial blood pressure signals during spinal anesthesia. Spinal anesthesia was performed with 0.5% bupivacaine (dosage at 13-15 mg). For CORAPS, SAP signals were simultaneously relayed to an analog-digital converter connected to a computer. Power spectral density of the data was computed using a fast Fourier transform. The areas of the spectral peaks within each measurement were calculated as the follows: very low (BVLF, 0.01-0.08 Hz), low (BLF, 0.09-0.15 Hz), and high (BHF, 0.16-0.25 Hz).

RESULTS

During the time interval (S2 period) when spinal anesthesia was initiated and 15 min thereafter the power density of low frequency (BLF), (1.2 vs. 2.3), and very low frequency (BVLF) components decreased, (3.4 vs. 7.8), in comparison with that at the baseline level (S1 period). We also found the shift of dominance between low frequency (BLF) and high frequency (BHF) in S2 period. The effects of intrathoracic pressure on the venous return may contribute to the increase of power density of BHF components (1.7 vs. 1.1). We also found that even in patients with stable hemodynamic variability, the decrease of BLF and BVLF components, and the shift of dominance were the same as in patients with unstable hemodynamic variability.

CONCLUSIONS

It might prove that the cephalic spread of spinal block abolished the sympathetic tone of the autonomic nervous system. These results validated previous speculations of a sympathetic block during spinal anesthesia. More importantly, patients with stable hemodynamic variability still have profoundly sympathetic block with decreased power density of BLF and BVLF. The CORAPS is a good clinical monitoring tool to evaluate the homeostatsis of cardiac neuroregulation after spinal anesthesia.

Minimally invasive cardiac surgical techniques in the closure of ventricular septal defect: an alternative approach

BACKGROUND

Minimally invasive cardiac surgical techniques recently have been applied in the management of a variety of intracardiac lesions.

METHODS

Fourteen patients (6 boys and 8 girls; age, 8.9 +/- 5.5 years; body weight, 29.0 +/- 13.5 kg) were operated on using minimally invasive cardiac surgical techniques for the closure of a ventricular septal defect (subarterial in 11 patients and perimembranous in 3 patients). The operations were performed through a left anterior minithoracotomy and were guided by video-assisted endoscopic techniques under femorofemoral cardiopulmonary bypass. The myocardium was protected by continuous coronary perfusion with hypothermic fibrillatory arrest. The right ventricular outflow tract was entered after pericardiotomy was performed.

RESULTS

Closure of the defect (directly in 4 patients and by patch in 10 patients) was performed successfully in all patients. A right ventricular outflow tract obstruction and ruptured sinus of Valsalva aneurysm also were repaired in 1 patient each. The duration of cardiopulmonary bypass was 41 +/- 10 minutes (range, 28 to 100 minutes) and the total operative time was 2.2 +/- 0.8 hours (range, 1.3 to 3.5 hours). All the patients recovered rapidly from their operation and had an uneventful postoperative course. Follow-up (mean, 6.2 months; range, 6 to 9 months) was complete in all patients. There were no late deaths. Transthoracic echocardiographic examination showed no residual shunt and no aortic regurgitation in all patients.

CONCLUSIONS

Our experience demonstrates that minimally invasive cardiac surgical techniques are technically feasible and an alternative option for the repair of a ventricular septal defect.

Minimally invasive approach for coronary artery bypass surgery

Forty-two patients, 33 male and 9 female, aged 35.7 to 81.6 years old (mean 62.7), were operated on for left main and/or triple vessel coronary artery disease by using minimally invasive cardiac surgical techniques. A myocardial infarction had occurred in 26 patients (61.9%). The left ventricular ejection fraction ranged from 17 to 83% (52+/-22). The surgeries were performed through left parasternal minithoracotomy (8 to 12 cm in length) under femoro-femoral or aorto-atrial cardiopulmonary bypass. The myocardium was protected by blood cardioplegic solution with the aorta crossclamped. Under direct vision, average 3.8 distal anastomoses were performed in each patient, with the saphenous vein grafts and the left internal thoracic arterial graft. The aortic crossclamp time was 62 to 137 min (80+/-15). The duration of cardiopulmonary bypass was 88 to 168 min (115+/-24). The postoperative course was uneventful in all patients. Follow-up (1.0 to 5.6 months, mean 2.9) was complete in all patients and there were no late deaths or angina. Coronary angiography of ten patients showed patent grafts. Our experience demonstrates that minimally invasive cardiac surgery during cardioplegic arrest is technically feasible and can be performed in coronary artery disease safely and effectively for complete revascularization.

Video-assisted coronary artery bypass grafting during hypothermic fibrillatory arrest

BACKGROUND

Hypothermic fibrillatory arrest without aortic cross-clamping is a technique for quieting the heart during coronary artery bypass grafting. This report reviews the preliminary results with this technique in 4 patients having video-assisted coronary artery bypass grafting.

METHODS

Four male patients 28.5 to 64.5 years old (mean age, 45.4 years) underwent operation for unstable angina. With video-assisted techniques, coronary artery bypass grafting was performed through a left anterior minithoracotomy with femoral-femoral cardiopulmonary bypass without cross-clamping the aorta. The myocardium was protected by continuous coronary perfusion during hypothermic fibrillatory arrest.

RESULTS

A left internal thoracic artery graft was anastomosed to the left anterior descending coronary artery in each patient. The posterior descending branch of the right coronary artery was grafted with a pedicled right gastroepiploic artery in 1 patient. The duration of cardiopulmonary bypass was 72 to 127 minutes (mean duration, 92 +/- 21 minutes). The postoperative course of each patient was uneventful. Follow-up (range, 3.9 to 5.8 months; mean follow-up, 4.9 months) was complete for all patients. There were no late deaths. Coronary angiography showed patent grafts. All patients were in New York Heart Association functional class I or II (mean class, 1.25).

CONCLUSIONS

Hypothermic fibrillatory arrest is a simple and effective method of quieting the heart, thereby providing a motionless operative field for video-assisted coronary artery bypass grafting.

High frequency jet ventilation for severe pulmonary hemorrhage during aortic dissection operation--a case report

Massive endobronchial bleeding during extracorporeal circulation was encountered in a patient during aortic dissection operation. The use of high frequency jet ventilation resulted in successful staunching of the bleeding, thus avoiding the need of pneumonectomy or lobectomy.

Video-assisted cardiac surgery in closure of atrial septal defect

BACKGROUND

Video-assisted endoscopy has been applied in the management of a variety of intrathoracic vascular lesions. Here we report its use in the correction of intracardiac congenital defects.

METHODS

Eight patients (3 male and 5 female) underwent operation for closure of an atrial septal defect. The patients ranged in age from 2.0 to 60.9 years (mean, 19.2 +/- 19.0 years). The patients weighed 11 to 66 kg (mean, 41.3 +/- 23.5 kg). The ratio of pulmonary blood flow to systemic blood flow ranged from 2.0 to 6.0 (mean, 3.4 +/- 1.3). The mean pulmonary artery pressure was 19.7 +/- 4.0 mm Hg (range, 13 to 24 mm Hg). The operations were performed through a right anterior minithoracotomy and guided by video-assisted endoscopic techniques under femorofemoral or femoral-right atrial extracorporeal circulation. The aorta was not cross-clamped, and the myocardium was protected by continuous coronary perfusion with hypothermic fibrillatory arrest (rectal temperature, 22.0 degrees +/- 2.0 degrees C). Transesophageal echocardiographic monitoring was maintained during the operations. The right atrium was entered after pericardiotomy. Primary closure of the defect was performed successfully in all patients. Conventional nondisposable instruments were used for dissection, grasping, suturing, and hemostasis.

RESULTS

The durations of extracorporeal circulation and operation ranged from 47 to 126 minutes (mean, 80 +/- 31 minutes) and from 2.2 to 4.5 hours (mean, 3.1 +/- 0.8), respectively. All patients recovered from the operation rapidly with an uneventful postoperative course.

CONCLUSIONS

Our experience demonstrates that video-assisted cardiac surgery is technically feasible and can be used with excellent results for the repair of congenital heart defects in general.

Video-assisted mitral valve operations

BACKGROUND

Video-assisted endoscopy has been applied frequently in the management of a variety of surgical diseases. However, it has rarely been applied in mitral valve surgery.

METHODS

We report 2 patients who received emergency operations for thrombosis of a mitral prosthesis (patient 1, a 68-year-old man) and acute mitral regurgitation due to rupture of anterior chordae (patient 2, a 75-year-old woman). They both had severe congestive heart failure. Cardiogenic shock was noted in patient 2. The mitral valve was approached through a right anterior minithoracotomy with the aid of an endoscope by means of projected images on the video monitor under femorofemoral cardiopulmonary bypass. The aorta was not cross-clamped, and the myocardium was protected by continuous coronary perfusion with hypothermic fibrillatory arrest. The left atrium was entered posterior to the interatrial groove. Thrombectomy and mitral valve repair were performed successfully.

RESULTS

The duration of extracorporeal circulation was 204 and 147 minutes, respectively. Both patients recovered from the operation rapidly with uneventful postoperative courses.

CONCLUSIONS

Our preliminary results suggest that video-assisted endoscopic cardiac surgery is technically feasible and could be performed in the milieu of open heart surgery.

Double-lumen endotracheal tube intubation in difficult intubation-use the WuScope System: a case report

Although not an absolute requirement in most cases, there are many anesthetic and surgical advantages for using a double-lumen tube during intrathoracic operations. It is almost impossible that double-lumen tube intubation by conventional methods in patients whose glottis can not be visualized by direct laryngoscopy. We describe the previously unreported method by using The WuScope System for double-lumen endotracheal tube intubation in a patient with acromegaly and difficult airway.

Power spectral analysis of systemic arterial pressure signals during open heart surgery

BACKGROUND

The close relationship between the balance of sympathetic and parasympathetic tones and the results of power spectral analysis (PSA) of systemic arterial pressure (SAP) has been suggested recently. The purpose of this study was to further describe the changes of balance between the two autonomic nervous components during open heart surgery for coronary arterial disease (CAD) or valvular heart disease (VHD) with the PSA technique of SAP.

METHODS

By relaying the SAP signals to a personal computer utilizing a power spectral analysis algorithm, radial arterial pressure signals of 27 patients (11 with CAD for coronary artrial bypass graft, as CAD groups; 16 with VHD, as VHD group, including 8 for aortic valve replacement and 8 for mitral valve replacement) during open heart surgery were monitored in a continuous, on-line and real-time manner. On-line power spectral analysis was performed according to the five different stages of the operation.

RESULTS

Power density tended to increase in the high frequency (HF) band during the ventilator-supported stages of the open heart procedures, i.e., the pre-cardiopulmonary bypass (CPB) and the off-CPB periods. The power density in other frequency bands during the whole course of general anesthesia otherwise decreased significantly, with the lowest values occurring during CPB. The power density in very low frequency (VLF) band was much higher than in other bands during CPB, and became the major component of total power density in this period.

CONCLUSIONS

The balance between sympathetic and parasympathetic components of autonomic nervous system changes rapidly during open heart surgery and needs careful monitoring. By utilizing PSA of SAP, mathematical error might be an obstacle of using LF:HF ratio as an index of autonomic balance during the CPB period when the HF density approaches zero.

Continuous, on-line, real-time spectral analysis of SAP signals during cardiopulmonary bypass

We communicated the application of continuous, on-line, real-time power spectral analysis of systemic arterial pressure (SAP) signals during cardiopulmonary bypass when the heart was functionally but reversibly disconnected from the blood vessels. Based on observations from 15 cases of successfully completed coronary artery bypass grafting procedures, we found that the very low (0.00-0.08 Hz), low (0.08-0.15 Hz)-, high (0.15-0.25 Hz)-, and very high (0.80-1.60 Hz) frequency components of SAP signals exhibited differential changes before, during, and after cardiopulmonary bypass. In particular, the very low-frequency component, which purportedly represents the contribution of vasomotor activity to SAP, presented only a mild decrease in power during hypothermic cardioplegia. Interestingly, the total peripheral resistance also manifested only a slight reduction during the same period. On the other hand, the low-, high-, and very high frequency components were essentially eliminated. These results unveiled an active role for the blood vessels in the maintenance of SAP during cardiopulmonary bypass, possibly as a result of a maintained vasomotor tone as reflected by the sustained very low frequency component of the SAP signals.

Effects of zaizhang-I, a traditional Chinese herbal medicine, on hematopoietic recovery from radiation injury in mice

Effects of Zaizhang-I (ZZ-I) on the recovery of hemopoietic systems from radiation injury were investigated. Mice, irradiated with 6.0 Gy-rays, were injected i.p. once daily for 7 consecutive days with either ZZ-I or saline (0.01 ml/g body wt.). The experiments showed that ZZ-I significantly promoted the recovery of not only peripheral WBC, BMC, CFU-S and CFU-GM but also the abnormal femur micro-vessel system such as blood vessels and sinus ectasia, hyperemia and hemorrhage etc. These results suggest that ZZ-I could accelerate hemopoietic recovery from radiation injury in mice by stimulating hemopoietic stem cells and improving hemopoietic inductive microenvironment (HIM).

The interaction of diazepam with vecuronium: a clinical study

BACKGROUND

Diazepam, known to possess myorelaxation property, has been widely used clinically to control muscular rigidity and spasticity. The interactions of diazepam with neuromuscular blocking agents have been extensively studied, yet the results reported are somewhat controversial and inconclusive.

METHODS

The interaction of diazepam with one of the neuromuscular blocking agents, vecuronium, was studied in 20 ASA I-II patients undergoing elective surgery. They were randomly assigned to two groups with ten in each group. Anesthesia was induced with fentanyl, thiopental and vecuronium and maintained with 1% halothane and 70% N2O in O2. The experimental group received diazepam (0.2 mg/kg) 3 minutes prior to vecuronium (0.1 mg/kg) during induction while the control group received vecuronium (0.1 mg/kg) straight without diazepam. Control records of the integrated electromyography showed the response to train-of-four supramaximal stimulation by a Datex Relaxograph during induction. In no time when the first twitch (T1) recovered to 25% of the control, it was topped up again with another intraoperative dose of vecuronium (0.025 mg/kg). From the derived data, the following parameters were calculated and analysed: (1) onset time T10 (the time from the end of injection of vecuronium during induction to depression of T1 to 10% of control twitch height); (2) duration time T25 (the time from administering vecuronium during induction to the time when T1 recovered to 25% of the original twitch height); (3) topup time T25-25 (the time from administering the top dose of vecuronium to the time when T1 returned to 25% of control twitch height again) and (4) recovery time T25-50 (the time of recovery of T1 from 25% to 50% of the control twitch height at the end of the operation).

RESULTS

Significant differences between both groups were found in T10 (221.8 +/- 62.2 vs 135.4 +/- 23.3 sec, p < 0.01) and T25 (41.9 +/- 10.2 vs 50.6 +/- 9.4 min, p < 0.05). The results of T25-25 and T25-50 did not differ much (26.6 +/- 6.9 vs 29.3 +/- 4.4 min, p > 0.05 and 15.0 +/- 8.9 vs 16.9 +/- 8.7 min, p > 0.05 respectively).

CONCLUSIONS

The administration of diazepam (0.2 mg/kg) three minutes prior to vecuronium (0.1 mg/kg) during induction may hasten the onset of vecuronium and prolong its duration of action.

Early detection of the tip position and complication of the intra-aortic balloon pump catheter by perioperative transesophageal echocardiography

BACKGROUND

Intraoperative verification of the precise balloon position of intra-aortic balloon pump(IABP) is necessary and important. We introduced transesophageal echocardiogram (TEE) as one of our routine intraoperative image monitor to accomplish this identification fluently, conveniently and also precisely.

METHODS

56 patients who needed the hemodynamic support when weaning the cardiopulmonary bypass were introduced to receive IABP and the balloon position was verified by TEE. To confirm the accurate location, the position of balloon tip was rechecked with postoperative portable chest x-ray.

RESULTS

The balloon tip was attempted to locate in the proximal descending aorta, which was verified via TEE to be successful in 98.1% of patients by postoperative chest x-ray. Five (8.9%) patients failed to pass the balloon catheter at the first time due to high arterial resistance. One iatrogenic aortic dissection (1.8%) and one case in the wrong lumen (1.8%) were detected by TEE. No early death was contributed to IABP insertion.

CONCLUSIONS

The application of TEE in the perioperative period helps not only detect IABP complication early but also verify of balloon catheter position quickly. It can replace the conventional role of fluorography.

A comparison between vecuronium and atracurium in myasthenia gravis

We evaluated the effect of vecuronium bromide and atracurium besylate on the train-of-four response in the management of muscle relaxation in 20 patients with myasthenia gravis (MG) who were undergoing thymectomy. We confirmed the safe use of these two non-depolarizing muscle relaxants in MG patients. Vecuronium (0.04 mg.kg-1) demonstrated a lesser clinical duration than did atracurium (0.2 mg.kg-1) (38 +/- 19 vs 50 +/- 21 min, mean +/- s.e.mean). The recovery time for vecuronium patients was shorter than that for atracurium patients (22 +/- 18 vs 38 +/- 18 min), but the time until onset of neuromuscular blockade was longer with vecuronium (246 +/- 105 vs 107 +/- 103 s). During spontaneous recovery from neuromuscular relaxation, at T1/C of 25% and 100%, the train-of-four fade with vecuronium was significantly greater than that with atracurium (0.04 +/- 0.02, 0.16 +/- 0.03 vs 0.17 +/- 0.01, 0.83 +/- 0.03), suggesting that vecuronium had a greater prejunctional effect than did atracurium.

The use of transesophageal echocardiography to evaluate the effectiveness of patent ductus arteriosus ligation

The ligation of patent ductus arteriosus (PDA) is a comparatively easy operation, but some complications are possible. The most common complication is incomplete ligation of the PDA; others include inadvertent ligation of the descending aorta or left pulmonary artery, transient rise in systemic blood pressure and increased left ventricular afterload, and acute right heart failure due to pulmonary hypertension. The completeness of the PDA ligation is usually determined only by the operating physician's experience, including the use of an esophageal stethoscope or a finger on the lesion to feel for vibration. These methods sometimes fail to detect an incomplete ligation. With transesophageal echocardiography (TEE), we have monitored the entire course of the PDA ligation directly without interrupting the surgical procedure, and precisely determined the completeness of the ligation. We also expect that TEE will enable us to avoid other complications as well.

[Mannitol reduces plasma hydrogen peroxide free radical in patients undergoing coronary artery bypass graft surgery]

During the procedure of coronary artery bypass graft surgery (CABG), the release of free oxygen radicals as a result of ischemia and reperfusion which plants the seeds of post-operative low cardiac output and arrhythmias has grave consequence on the reestablishment of cardiac function. A variety of chemical agents such as mannitol, allopurinol, catalase (Q-10) and superoxide dismutase (SOD) has proved to be considerably effective to improve the myocardial necrosis following ischemia and reperfusion. In this study we chose mannitol (0.2 gm/kg) as the free oxygen radicals scavenger and utilized mass spectrophotometric method to detect the variation of concentration of [H2O2], a by-product of free oxygen radical, in an attempt to evaluate the efficacy of mannitol in this regard in patients undergoing CABG. Patients were divided into experimental group (n = 19) and control group (n = 20). In the experimental group the concentration of [H2O2] changed from 61 +/- 24 microM/L pre-operatively to 77 +/- 18 microM/L post-operatively as against 75 +/- 31 microM/L and 99 +/- 31 microM/L respectively in the control group. In comparison, only the change in experimental group was statistically significant (p less than 0.05). We confirmed that mannitol functions considerably as a free oxygen radical scavenger since it reduces the production of [H2O2] in patients undergoing CABG.

Interpleural administration of bupivacaine for postoperative analgesia after thoracotomy in patients with patent ductus arteriosus

Interpleural analgesia for postoperative pain with bupivacaine 0.25%, 0.375% and 0.5% at dosage of 1.5 mg/kg was evaluated in three randomized groups (A, B and C) of 22 children having triple ligation for patent ductus arteriosus (PDA). Complete pain relief was obtained within 30 min irrespective of the concentration of bupivacaine. The duration of pain relief significantly varied with the concentrations of the drug used, respectively 5.02 +/- 0.4 h, 6.88 +/- 0.7 h and 8.24 +/- 1.08 h (mean +/- SD) for 0.25%, 0.375% and 0.5% bupivacaine (p less than 0.05). No side effects were observed and no other supplemented narcotics were given. We concluded that 0.5% bupivacaine at the dose of 1.5 mg/kg was effective in postoperative pain relief after thoracotomy in patients undergoing PDA ligation surgery.

Thromboelastogram fails to predict postoperative hemorrhage in cardiac patients

To determine the clinical usefulness of the thromboelastogram in the prediction of postoperative hemorrhage in cardiac patients, we related the results of routine coagulation tests (RCTs) and thromboelastography with the amount of chest tube drainage postoperatively in 101 patients requiring cardiopulmonary bypass. Our data indicated that there was no correlation between RCT results and thromboelastographic variables. No single variable of RCTs and thromboelastography correlated well with the amount of chest tube drainage postoperatively. Before the onset of cardiopulmonary bypass, the most frequent abnormalities detected by thromboelastograms were fibrinolysis and hypocoagulability resulting from factor deficiency. Hypercoagulability detected by thromboelastograms occurred in 13% of patients after cardiopulmonary bypass and usually was not detected by RCTs. The incidence of false-negative thromboelastograms and RCT results in patients who had excessive hemorrhage of unknown cause was 46% and 52%, respectively. The incidence of fibrinolysis as detected by thromboelastograms was similar before and after bypass, but only 2 of the 18 patients with fibrinolysis had excessive hemorrhage postoperatively. Our results indicate that neither RCTs nor thromboelastography predicts the likelihood of excessive hemorrhage in patients after cardiopulmonary bypass. The thromboelastographic results should be interpreted cautiously because of the high rate of unreliable results.

Acute normovolemic hemodilution in coronary artery bypass graft surgery

Twenty patients undergoing coronary artery bypass graft (CABG) surgery in April through May, 1990 in our hospital were included in this study to evaluate the merits and practicability of autologous blood transfusion. About 1,000 ml of arterial blood were collected via a radial arterial line and stored in a plastic bag containing CPD solution immediately after induction of anesthesia. Colloid or crystalloid solution was used to replace the volume deficit after the blood sampling. At the end of cardiopulmonary bypass and after adequate reversal of heparinization by protamine, the blood previously sampled was re-transfused to the patient via a peripheral venous line. Thirty patients undergoing CABG surgery, who did not receive autologous blood transfusion from February to June, 1990 save April and May were assigned as control. Comparison of the data between the two groups was made using the Student's t-test. It was found that the intraoperative acute normovolemic hemodilution could lower the hematocrit by approximately 12%. Packed red blood cells (PRBC) given intraoperatively in the autologous group was only 2.0 +/- 0.4 units whereas it was 5.3 +/- 0.7 units in the control group (p less than 0.001). Fresh frozen plasma (FFP) given intraoperatively in the autologous group was only 1.8 +/- 0.5 units whereas it was 6.6 +/- 0.7 units in the control group (p less than 0.001). The amount of platelets given intraoperatively in the autologous group was 1.9 +/- 1.0 units against 9.3 +/- 1.4 units in the control group (p less than 0.001). Thus, acute normovolemic hemodilution in CABG surgery decreased intraoperative requirement of bank blood components including PRBC, FFP and platelets.(ABSTRACT TRUNCATED AT 250 WORDS)

Influence of controlled hypotension by adenosine triphosphate or nitroglycerin on the neuromuscular blocking effect of atracurium in dogs

The neuromuscular blocking effect of atracurium under the influence of controlled hypotension by adenosine triphosphate (ATP) or nitroglycerin (NTG) was studied in mongrel dogs under halothane anesthesia. Under hypotensive state (60 +/- 5 mmHg) elicited by ATP (0.5 mg/kg/min) or NTG (1 microgram/kg/min), the neuromuscular blockade produced by atracurium (30 micrograms/kg, i.v.) was significantly potentiated and prolonged. The maximal depression of twitch contraction of the gastrocnemius-soleus muscle increased from 10 +/- 3% to 36 +/- 10% (ATP group) and 56.0 +/- 2.4% (NTG group), while the duration of neuromuscular blockade was prolonged from 663 +/- 96 s to 1060 +/- 277 s (ATP group), and 1375 +/- 441 s (NTG group). The potentiation and prolongation of neuromuscular blockade by atracurium was still apparent upon reversal of the hypotensive effect of ATP, but not of NTG, by dopamine infusion. We suggest that ATP may prolong and augment the effect of atracurium by reducing the presynaptic release of acetylcholine at the neuromuscular junction.

Effect of an anti-lipoprotein lipase serum on plasma triglyceride removal

Anti-lipoprotein lipase sera injected intravenously in roosters blocked quantitatively the catabolism of very low density lipoprotein (VLDL) triglyceride. Antibodies were produced in rabbits immunized with highly purified lipoprotein lipase (LPL, glycerol ester hydrolase, E C 3.1.1.3) prepared from chicken adipose tissue. Following anti-LPL serum injection there was a linear increase in plasma triglyceride concentration. The rate of entry of triglyceride in plasma was estimated from the rate of triglyceride accumulation in the plasma of animals injected with anti-LPL serum, or from the disappearance curve of biologically labelled VLDL. In instances where both measurements were conducted in the same animals there was very close agreement between the two procedures. Inhibition of VLDL triglyceride catabolism of anti-LPL serum provided a way to characterize newly secreted VLDL that exhibited a broad spectrum of particle sizes with a median of 625 A degrees. They contained 76.2 +/- 1.2% triglyceride and had a high ratio of free to ester cholesterol (2.46 +/- 0.45). In control VLDL samples there was 46.1% triglyceride, and the ratio of free to ester cholesterol was 1.19. The complete inhibition of triglyceride removal by an antiserum prepared against adipose tissue LPL demonstrates that the NaCl-inhibited, serum-activated lipase prepared by affinity chromatography on heparin-Sepharose and concanavalin A-Sepharose columns is the enzyme responsible in vivo for the catabolism of VLDL triglyceride. Further, the kinetics of triglyceride accumulation in the plasma provide evidence that the site of degradation of VLDL triglyceride is within the plasma compartment.