(Circulation. 1997;96:562-568.)
© 1997 American Heart Association, Inc.
Articles |
Monitoring Considerations for Port-Access Cardiac Surgery
From the Department of Anesthesia (L.C.S.), Division of Cardiology (F.G. St. G.), and Department of Cardiothoracic Surgery (J.H.S., M.F.P., T.A.B., B.A.R., W.S.P.), Stanford (Calif) University School of Medicine, and the Division of Cardiothoracic Surgery, Palo Alto (Calif) Veterans Affairs Health Care System (M.F.P., T.A.B.).
Correspondence to Lawrence C. Siegel, MD, PO Box 117098, Burlingame, CA 94011-7098. E-mail lsiegel{at}leland.stanford.edu
 |
Abstract |
|---|
 Top Abstract IntroductionMethodsResultsReferences |
|---|
Background A method for monitoring patients was evaluated in a clinical trial of minimally invasive port-access cardiac surgery with closed chest endovascular cardiopulmonary bypass.
Methods and Results Cardiopulmonary bypass was conducted in 25 patients through femoral cannulas. An endovascular pulmonary artery vent was placed in the main pulmonary artery through a jugular vein. For mitral valve surgery, a catheter was placed in the coronary sinus for delivery of cardioplegia. A balloon catheter ("endoaortic clamp," EAC) used for occlusion of the ascending aorta, delivery of cardioplegia, aortic root venting, and pressure measurement was inserted through a femoral artery and initially positioned by use of fluoroscopy and transesophageal echocardiography (TEE). Potential migration of the EAC was monitored by (1) TEE of the ascending aorta, (2) pulsed-wave Doppler of the right carotid artery, (3) balloon pressure, (4) comparison of aortic root pressure and right radial artery pressure, and (5) fluoroscopy. TEE, fluoroscopy, and pressure measurement were effective in monitoring catheter insertion and position. With inadequate balloon inflation, migration of the EAC toward the aortic valve could be detected with TEE. During administration of cardioplegia, TEE showed movement of the balloon away from the aortic valve, and migration into the aortic arch was detectable with loss of carotid Doppler flow. Stability of EAC position was demonstrated with appropriate balloon volume. Cardioplegic solution was visualized in the aortic root, and aortic root pressure changed appropriately during administration of cardioplegia. Venous cannula position was optimized with TEE and endopulmonary vent flow measurement.
Conclusions An effective method has been developed for monitoring patients and the catheter system during port-access cardiac surgery.
Key Words: surgery • cardiopulmonary bypass • echocardiography • imaging
|
Introduction |
|---|
|
TopAbstractIntroductionMethodsResultsReferences |
|---|
Less invasive laparoscopic and thoracoscopic surgical procedures have been developed to minimize patient discomfort, shorten hospital stays and rehabilitation periods, and reduce healthcare costs. Until recently, such techniques have had only limited application in cardiac surgery because of the inability to provide cardiopulmonary bypass (CPB) and myocardial protection without a median sternotomy or major thoracotomy. A catheter-based system has been developed that permits closed-chest CPB and enables the heart to be arrested and protected with cardioplegic solution in a manner equivalent to that used in conventional open surgery. With this system, cardiac surgical procedures can be conducted through small thoracic ports or limited incisions. Monitoring techniques have been considered to complement this approach.1 In the present study, methods for monitoring patients and the newly developed catheter system were evaluated in clinical trials of port-access coronary artery bypass grafting surgery and port-access mitral valve repair or replacement operations.
|
Methods |
|---|
|
TopAbstractIntroductionMethodsResultsReferences |
|---|
With institutional ethics committee approvals and written informed consent obtained, 25 patients underwent general anesthesia for port-access cardiac surgical procedures. Fifteen patients were treated for symptomatic coronary artery disease with anastomosis of the left internal mammary artery to the left anterior descending coronary artery. Ten patients had mitral valve disease; 7 had mitral valve replacement, and 3 had mitral valve repair. The patient selection criteria, surgical techniques, and surgical results are reported elsewhere.2 3 4
Endovascular CPB and Cardioplegia System
A set of four catheters were used to permit CPB and cardioplegic
cardiac arrest without cannulation of the heart through the chest (Fig 1
). A 28F venous cannula (DLP) introduced through a
femoral vein was used for venous drainage. A centrifugal pump was
placed between the venous cannula and the venous reservoir to augment
venous drainage.5 Arterial inflow from the CPB
pump passed through a 24F femoral arterial cannula
(Endoarterial Return Cannula, Heartport). A 10.5F
preshaped, triple-lumen, balloon-tipped catheter (Endoaortic Clamp,
Heartport) was used for endovascular occlusion of the ascending aorta,
delivery of cardioplegia into the aortic root, venting of the aortic
root, and aortic root pressure measurement. This catheter was
introduced through a side limb of the femoral arterial
cannula or through the contralateral femoral artery. An 8.3F preshaped,
single-lumen pulmonary artery vent catheter
(Endopulmonary Vent, Heartport) was introduced through a 9F
internal jugular vein introducer into the main pulmonary
artery. A 9F preshaped, triple-lumen catheter (Endosinus Catheter,
Heartport) was placed in the coronary sinus through an 11F
right internal jugular vein introducer to deliver cardioplegic solution
in a retrograde fashion. The three lumens permitted balloon inflation,
cardioplegia delivery, and coronary sinus pressure measurement.
Fig 2 shows the connection of these catheters to
complete the CPB circuit.
|
|
Insertion of Catheters for Endovascular CPB
Insertion techniques were developed for each catheter to
facilitate rapid and safe placement. A surgeon passed the venous
cannula through a femoral vein, and biplane or omniplane
transesophageal echocardiography
(TEE) or fluoroscopic guidance was used for positioning at the junction
of the superior vena cava and right atrium. After surgical exposure,
the arterial cannula was placed directly into the femoral
artery by a surgeon. Passage of this catheter could be facilitated by
first passing a guide wire through the femoral artery. Visualization of
the guide wire in the descending thoracic aorta provided confirmation
of the proper location of the wire before advancement of the cannula.
The pulmonary vent catheter was preloaded with a 110-cm 5F
double-lumen, balloon-tipped catheter (AI-07124, Arrow, or WMC904-5P,
World Medical) that served as a guide across the tricuspid and pulmonic
valves. Measurement of the distal catheter pressure aided catheter
manipulations. Fluoroscopy and TEE were also used to facilitate
catheter insertion. After proper insertion of the pulmonary
vent in the main pulmonary artery, the 5F introducing catheter
was removed to provide maximal vent catheter flow capacity. The
coronary sinus catheter was advanced into the right atrium and
positioned in the coronary sinus by visualization with TEE and
fluoroscopy (30° left anterior oblique when possible). Positioning
was also facilitated by observation of the distal catheter tip
pressure, which made undesired passage into the right ventricle
immediately apparent. If necessary, a guide wire was used to direct the
catheter.
Monitoring During Endovascular CPB
To ensure safe and adequate CPB, monitoring techniques were used
to evaluate venous drainage, arterial flow, venting,
cardioplegia delivery, aortic occlusion, regional perfusion, and
possible tissue trauma. Measurements included pressures and flows, and
imaging was done through fluoroscopy, TEE, direct inspection, and video
thoracoscopy. Venous drainage was evaluated with measurement of
centrifugal pump flow, inlet pressure of the centrifugal pump, right
atrial pressure, pulmonary vent flow, radial artery pressure,
TEE of the cardiac chamber size, and direct and video-assisted visual
inspection. The venous cannula position was monitored with TEE imaging,
and surgical palpation through the right thoracic incision was possible
in mitral valve operations. Arterial flow was evaluated
with measurement of CPB pump flow and pressure and radial artery
pressure. Pulmonary artery venting was evaluated with
measurement of flow by use of a transit time ultrasonic flowmeter
(Transonic Systems) and outlet pressure. Venting of the aortic root was
evaluated by consideration of flow and aortic root pressure. Venting
was also evaluated by direct inspection. Delivery of cardioplegia in
either an antegrade or retrograde fashion was evaluated by measurement
of cardioplegia pump flow and pressure and distal catheter pressures.
Cardioplegia flow was visualized by TEE, and myocardial temperature and
ECG were monitored for evidence of effective cardioplegia delivery. The
balloon on the coronary sinus catheter was deflated at the
conclusion of delivery of each dose of cardioplegia and was reinflated
for subsequent dosage.
Adequate balloon catheter occlusion of the ascending aorta was evaluated by comparison of simultaneous measurement of aortic root and radial artery pressures. Balloon pressure was observed to verify static inflation. TEE and color-flow Doppler were used to visualize the balloon in the ascending aorta and to detect leakage around the balloon. Multiple monitoring techniques were used to verify proper positioning of the balloon in the ascending aorta and to verify unimpeded blood flow to the aortic arch vessels. Right radial artery pressure was observed to detect migration of the balloon and obstruction of the brachiocephalic artery. Surface pulsed-wave Doppler of the right carotid artery was used to verify cerebral perfusion. TEE was used to visualize the ascending aorta and the location of the balloon within it. Possible trauma to the aortic valve or aorta by the balloon occlusion catheter was screened for with TEE.
Monitoring After CPB
Patients were weaned from CPB with the aid of TEE and
pulmonary artery pressure measurements. TEE was used to
evaluate ventricular and valvular function after
separation from CPB. After removal of the catheters, a thermodilution
pulmonary artery catheter was inserted when deemed necessary
for postoperative management.
|
Results |
|---|
|
TopAbstractIntroductionMethodsResultsReferences |
|---|
Monitoring Placement of Catheters for Endovascular CPB
The pulmonary vent catheter was successfully placed in 24 patients. Attempts at placement in 1 patient with a permanent pacemaker were abandoned because of concern about potential dislodgment of the pacemaker lead. Although placement of the pulmonary vent catheter was accomplished without fluoroscopy in 10 patients, radiographic visualization proved useful in orienting the preformed curvature of the vent catheter appropriately in the right ventricle (Fig 3
). The coronary sinus catheter
was placed successfully in all 10 patients undergoing mitral valve
surgery. Fluoroscopy, TEE, and distal catheter pressure measurement all
proved useful (Fig 4). During insertion, pressure
measurement revealed that the catheter tip passed to the right
ventricle at least once in all 10 patients. Fluoroscopy was used
primarily in 7 patients; TEE was used primarily in 3 patients. A guide
wire was used in only 1 patient to advance the coronary sinus
catheter, which initially engaged the ostium of the coronary
sinus but did not readily advance because of the presence of a
prominent thebesian valve. One patient was noted on TEE to have a large
(2.5-cm diameter) coronary sinus. Insertion of the
coronary sinus catheter and injection of x-ray contrast
revealed a left superior vena cava draining into the coronary
sinus, precluding infusion of cardioplegic solution.6 In
this patient, a pulmonary vent catheter was placed into the
pulmonary artery through the right internal jugular vein, and
another 8.3F vent catheter was placed at the junction of the left
superior vena cava and coronary sinus through the left internal
jugular vein to ensure adequate venous drainage. Early in the study, an
additional patient who was enrolled for port-access mitral valve repair
was withdrawn before the start of the operation because during
attempted placement of the coronary sinus catheter the
fluoroscopic image was suggestive of possible cardiac perforation. The
TEE images indicated that the catheter tip was located in the right
atrium, but for patient safety, a conventional approach to surgery was
taken. Direct surgical inspection revealed no cardiac perforation and
that the catheter tip was situated in the right atrium.
|
|
Initial surgical experience with direct insertion of the
arterial return cannula through a femoral arteriotomy
without the use of a guide wire demonstrated occasional difficulty in
advancing the narrow-tipped cannula obturator beyond the orifices of
arterial side branches, leading to potential
arterial avulsion or dissection. Insertion was facilitated
by passage of a guide wire and imaging of the guide wire in the
descending thoracic aorta with TEE or fluoroscopy to ensure optimal
tracking of the cannula. This method proved easy and effective, and
imaging of the wire with TEE was successful in all seven patients in
whom it was attempted. In all patients, the femoral venous cannula was
readily visualized in the heart and vena cava with fluoroscopy and TEE,
allowing safe positioning (Fig 5). TEE and fluoroscopy
permitted rapid initial positioning of the endoaortic clamp in the
ascending aorta (Fig 6).
|
|
Monitoring During Endovascular CPB
Inadequate venous drainage was most frequently detected (in four
patients) after initiating CPB and was typically corrected by
repositioning of the venous cannula. Inadequate venous drainage was
indicated by (1) venous pump flow remaining low despite adequate
negative inlet pressure on the centrifugal pump, (2) inadequate
decrease of central venous pressure, (3) pulmonary vent
catheter flow >270 mL/min and not decreasing, (4) radial artery
pressure remaining pulsatile, (5) TEE showing a nonempty right
ventricle, and (6) lack of right atrial and ventricular
decompression as demonstrated by video-assisted thoracoscopy. Optimal
repositioning of the venous cannula was guided by monitoring for
improvement in these observations, visualization of the cannula by TEE,
and, in the case of mitral surgery, by palpation of the cannula tip. On
two occasions, venous drainage was initially adequate but became
suboptimal later during CPB and was restored with movement of the
venous cannula by 1 to 2 cm. Monitoring of pulmonary vent flow
was particularly helpful in guiding such repositioning. Adequacy of
arterial flow was readily evaluated by
simultaneous observation of the CPB pump flow, CPB pump
outlet pressure, and radial artery pressure. Effectiveness of venting
was readily surmised by TEE examination of heart chamber size and
observation of the surgical field. Pulmonary vent flows
persistently >150 mL/min were investigated as possible venous drainage
problems. Pulmonary vent outlet pressure was negative during
proper vent function, and positive readings were used to detect
improper pulmonary vent pump action on two occasions during
which the pulmonary vent flowmeter recorded no flow. Aortic
root pressure measurement provided evidence of adequate aortic root
venting. The aortic root vent pump was adjusted to keep the aortic root
pressure from becoming negative to avoid drawing air into the aortic
root.
Cardioplegia could be visualized by TEE when delivered into the aortic root or into the coronary sinus owing to the presence of microbubbles in all cases. Coronary sinus pressure changed appropriately as cardioplegic flow was changed. Monitoring of coronary sinus pressure demonstrated proper occlusion of the coronary sinus on reinflation of the balloon. Myocardial temperature monitoring was used in 10 patients and indicated adequate myocardial cooling after delivery of cold cardioplegic solution confirmed by electrical standstill on the ECG.
Full inflation of the aortic occlusion balloon resulted in different pressures in the aortic root measured at the catheter tip and the right radial artery. Equalization of these pressures occurred when the balloon was deflated, and this phenomenon was used to detect inadequate balloon inflation. With proper occlusion, the radial artery pressure changed appropriately with variations in CPB pump flow, whereas the aortic root pressure changes coincided with antegrade cardioplegic flow and aortic root venting. Direct measurement of diminished balloon inflation pressure was indicative of loss of balloon volume in one patient, prompting immediate balloon catheter replacement. TEE imaging of the balloon in the ascending aorta confirmed proper occlusion with absence of Doppler color flow around the balloon.
After balloon inflation, CPB pump flow favored migration of the balloon
toward the aortic valve. During administration of antegrade
cardioplegia, pressurization of the aortic root tended to push the
balloon toward the aortic arch. In these circumstances, inadequate
balloon inflation was detected by movement of the balloon or catheter
tip. Migration toward the aortic valve was detected by TEE imaging of
the balloon in the ascending aorta (Fig 7). Movement of
the balloon away from the aortic valve during administration of
antegrade cardioplegia was detected on five occasions. This movement
was apparent on TEE, and in one patient, the Doppler signal in the
carotid artery showed absence of flow. By immediately stopping
cardioplegia delivery, the CPB pump flow pushed the balloon out of the
aortic arch toward the aortic valve, and flow through the carotid
artery was promptly reestablished. The balloon was then further
inflated, and subsequent cardioplegia delivery occurred without balloon
migration. In six patients, the balloon, once inflated, was not
visualized in the ascending aorta because of the limited length of
ascending aorta visualized with TEE. In these cases, the presence of
Doppler flow signal from the right carotid artery confirmed that
the balloon was properly positioned in the ascending aorta (Fig 8).
|
|
Weaning from CPB was easily accomplished in all patients with TEE-monitored intravascular volume repletion and pulmonary artery pressure measurement with the pulmonary vent catheter. After weaning from CPB, TEE examination of the ascending aorta showed no change in aortic caliber or apparent intimal damage. Color-flow Doppler examination of the aortic valve revealed no aortic valve injury or new incompetence.
Conclusions
Previous laboratory investigations have demonstrated the
feasibility of port-access cardiac surgery using the described
endovascular CPB system. Stevens et al7 demonstrated
port-access coronary artery surgery by using these methods to
anastomose the internal thoracic artery to the left anterior descending
coronary artery in 10 dogs. They also demonstrated feasibility
in seven human cadavers and proposed a surgical method applicable to
humans. This work was extended in a report of 23 dogs studied acutely
and 4 dogs recovered from surgery in which the internal mammary artery
was dissected using three 10-mm left lateral chest ports and a
thoracoscope.8 The anastomosis of this artery to the left
anterior descending coronary artery or first diagonal branch
was completed by use of two to four 5-mm ports for microvascular
instruments and a 10-mm port through which a modified microscope
provided stereo vision. Pathological examination showed no evidence of
aortic injury.8 Schwartz et al9 used
cardioplegic solution and compared 1 hour of external aortic clamping
with 1 hour of balloon aortic occlusion in dogs. No differences in left
ventricular function, myocardial temperatures, or
ultrastructural biopsy examinations were found when the two aortic
occlusion techniques were compared. The endovascular CPB system worked
well, as reported by Siegel et al10 in a summary of 54
dogs studied to complete several different port-access cardiac surgical
procedures. Pompili et al11 demonstrated the feasibility
of port-access mitral valve replacement in dogs using one 35x17-mm
oval port and two 10-mm lateral thoracic ports. Eleven dogs underwent
acute studies, and 4 dogs recovered for 1 month after surgery and had
transthoracic echocardiography that
demonstrated normal ventricular function and
prosthetic valve function.11
In contrast to using the endovascular CPB system described above for minimal access cardiac surgery, other surgical techniques have been pursued that include open-chest coronary artery bypass grafting on a beating heart without CPB,12 13 minimal-access coronary artery bypass grafting without CPB,14 15 and video-assisted mitral valve surgery with CPB and cardiac fibrillation.16 Open-chest coronary artery bypass grafting on a beating heart without CPB has been available for decades but has not achieved wide acceptance because of the technical demands of performing a precise arterial anastomosis and the potential for myocardial ischemia or infarction and hemodynamic decompensation intraoperatively. Minimal-access coronary artery bypass grafting without CPB eliminates the use of a median sternotomy but has potential problems similar to those of the open-chest procedure without CPB. Intraoperative considerations for these procedures include management of temporary coronary artery occlusion, significant hypotension, and bradycardia.17 18 19 20 21 Although morbidity is associated with the use of CPB, there is also the potential for immediate and long-term morbidity when cardiac surgery is performed without circulatory support. Arrest of the heart with cardioplegia is preferred to cardiac fibrillation during CPB to reduce myocardial oxygen consumption and to enhance myocardial protection. The techniques used in the present study provide all the features of CPB and myocardial protection used in open cardiac surgery and thus provide conditions most similar to those found in the current practice of cardiac surgery.
The monitoring techniques used in this study proved effective for allowing proper positioning and use of the elements of the endovascular CPB system. Although highly effective, modification of these methods or use of alternative monitoring methods might be desirable. In this study, monitoring of the aortic occlusion balloon position was accomplished with TEE imaging of the ascending aorta, right radial artery pressure measurement, and pulsed-wave Doppler examination of the right carotid artery. Alternatively, simultaneous comparison of right and left radial artery pressure measurements would provide information about balloon migration into the aortic arch. Other flow measurements could include Doppler flow measurement of the right temporal artery or middle cerebral artery. Adequacy of cerebral perfusion could be assessed with electroencephalography. These techniques would require evaluation for ease of use and accuracy. Nuttall et al22 demonstrated poor correlation of middle cerebral artery mean velocity obtained by trained transcranial Doppler technicians and cerebral blood flow measured with the Kety-Schmidt nitrous oxide method during hypothermic nonpulsatile CPB.
Monitoring considerations should be addressed in further technical development of the endovascular CPB system. Selection of materials to facilitate catheter visualization by TEE and fluoroscopy would be desirable. Further optimization of imaging methods should be pursued. Increased clinical experience should create a better understanding of the effectiveness of monitoring methods and their appropriate role during port-access cardiac surgical procedures. Technical improvements to the endovascular CPB system that allow a greater range of system performance with high reliability should reduce the frequency with which troubleshooting must be undertaken. Clinical studies are in progress to evaluate the safety and effectiveness of port-access cardiac surgical procedures. Clinical investigation is necessary to optimize clinical care to reduce patient suffering, to facilitate rapid rehabilitation, and to define what benefits patients may derive from this approach. Continued development of monitoring methods to complement these procedures will play a vital role.
|
Acknowledgments |
|---|
This study was supported by a grant from Heartport, Inc.
Received November 12, 1996; revision received February 3, 1997; accepted February 7, 1997.
|
References |
|---|
|
TopAbstractIntroductionMethodsResultsReferences |
|---|
1. Siegel LC, Peters WS, St Goar FG, Stevens JH, Pompili MF, Howard SK, Burdon TA, Ribakove GH, Mitchell RS. Anesthetic considerations for port-access cardiac surgery. Anesth Analg. 1996;82:SCA79. Abstract.
2. St Goar FG, Stevens JH, Burdon TA, Siegel LC, Pompili MF, Peters W, Reitz BA. Closed-chest CABG clinical characteristics: potential for procedural synergy in managing CAD. J Am Coll Cardiol. 1996;27:392A. Abstract.
3. Reitz BA, Stevens JH, Burdon TA, St Goar FG, Siegel LC, Pompili MF. Port-access coronary artery bypass grafting: lessons learned in a phase I clinical trial. Circulation. 1996;94(suppl I):I-294. Abstract.
4. Pompili MF, Yakub A, Siegel LC, Stevens JH, Awang Y, Burdon TA. Port-access mitral valve replacement: initial clinical experience. Circulation. 1996;94(suppl I):I-3122. Abstract.
5. Toomasian JM, Conte JV, Reitz BA. Kinetic assisted venous drainage as an adjunct to multiple redo sternotomy. In: Toomasian JM, Stafford TB, Kurusz M, eds. Case Reports: Clinical Studies in Extracorporeal Circulation. Houston, Tex: PREF Press; 1996;2:1-10.
6. Hasel R, Barash PG. Dilated coronary sinus on prebypass transesophageal echocardiography. J Cardiothorac Vasc Anesth. 1996;10:432-435.[Medline] [Order article via Infotrieve]
7.
Stevens JH, Burdon TA, Peters WS, Siegel LC, Pompili
MF, Vierra MA, St Goar FG, Ribakove GH, Mitchell RS, Reitz BA.
Port-access coronary artery bypass grafting: a proposed
surgical method. J Thorac Cardiovasc Surg. 1996;111:567-573.
8.
Stevens JH, Burdon TA, Siegel LC, Peters WS, Pompili
MF, St Goar FG, Berry GJ, Ribakove GH, Vierra MA, Mitchell RS,
Toomasian JM, Sterman WD, Reitz BA. Port-access coronary
artery bypass with cardioplegic arrest: acute and chronic canine
studies. Ann Thorac Surg. 1996;62:435-441.
9.
Schwartz DS, Ribakove GH, Grossi EA, Stevens JH,
Siegel LC, St Goar FG, Peters WS, McLaughlin P, Baumann FG, Colvin SB,
Galloway AC. Minimally invasive cardiopulmonary bypass
with cardioplegic arrest: a closed chest technique with equivalent
myocardial protection. J Thorac Cardiovasc
Surg. 1996;111:556-566.
10. Siegel LC, Peters WS, Stevens JH, St Goar FG, Burdon TA, Pompili MF, Reitz BA. Endovascular cardiopulmonary bypass with cardioplegia and cardiac venting: experience in canine and bovine port-access cardiac surgical procedures. Anesthesiology. 1996;35:A593. Abstract.
11.
Pompili MF, Stevens JS, Burdon TA, Siegel LC, Peters
WS, Ribakove GH, Reitz BA. Port-access mitral valve replacement
in dogs. J Thorac Cardiovasc Surg. 1996;112:1268-1274.
12.
Benetti FJ, Naseli G, Wood M, Geffner L. Direct
myocardial revascularization without extracorporeal
circulation: experience in 700 patients. Chest. 1991;100:312-316.
13. Moshovitz Y, Lusky A, Mohr R. Coronary artery bypass without cardiopulmonary bypass: analysis of short-term and mid-term outcome in 220 patients. J Thorac Cardiovasc Surg. 1995;10:979-987.
14.
Acuff TE, Landreneau RJ, Griffith BP, Mack MJ.
Minimally invasive coronary artery bypass grafting.
Ann Thorac Surg. 1996;61:135-137.
15. Robinson MC, Gross DR, Zemen W, Stedje-Larsen E. Minimally invasive coronary artery bypass grafting: a new method using an anterior mediastinotomy. J Card Surg. 1995;10:529-536.[Medline] [Order article via Infotrieve]
16.
Lin PJ, Chang CH, Chu JJ, Liu HP, Tsai FC, Chu PH,
Chiang CW, Yang MW, Shyr MH, Tan PPC. Video-assisted mitral
valve operations. Ann Thorac Surg. 1996;61:1781-1787.
17. Gayes JM, Emery RW, Nissen MD. Anesthetic considerations for patients undergoing minimally invasive coronary artery bypass surgery: mini-sternotomy and mini-thoracotomy approaches. J Cardiothorac Vasc Anesth. 1996;10:531-535.[Medline] [Order article via Infotrieve]
18. Wasnick JD, Hoffman WJ, Acuff T, Mack M. Anesthetic management of coronary artery bypass via minithoracotomy with video assistance. J Cardiothorac Vasc Anesth. 1995;9:731-733.[Medline] [Order article via Infotrieve]
19. Hensley FA. Minimally invasive myocardial revascularization surgery: here to stay? J Cardiothorac Vasc Anesth. 1996;10:445-446.[Medline] [Order article via Infotrieve]
20. Greenspun HG, Adourian AUA, Fonger JD, Fan JS. Minimally invasive direct coronary artery bypass (MIDCAB): surgical techniques and anesthetic considerations. J Cardiothorac Vasc Anesth. 1996;10:507-509.[Medline] [Order article via Infotrieve]
21. Martin HB, Walter CL. Preconditioning: an endogenous defense against the insult of myocardial ischemia. Anesth Analg. 1996;83:639-645.[Medline] [Order article via Infotrieve]
22. Nuttall GA, Cook DJ, Fulgham JR, Oliver WC, Proper JA. The relationship between cerebral blood flow and transcranial Doppler blood flow velocity during hypothermic cardiopulmonary bypass in adults. Anesth Analg. 1996;82:1146-1151.[Abstract]
This article has been cited by other articles:
 |
|
 |
|
  J. W. Hammon Extracorporeal Circulation: Perfusion System Card. Surg. Adult, January 1, 2008; 3(2008): 350 - 370. [Full Text]
|
|
|
|
 |
|
 D. D. Doblar Intraoperative Transcranial Ultrasonic Monitoring for Cardiac and Vascular Surgery Seminars in Cardiothoracic and Vascular Anesthesia, June 1, 2004; 8(2): 127 - 145. [Abstract] [PDF]
|
|
|
|
 |
|
 F. P. Casselman, S. V. Slycke, H. Dom, D. L. Lambrechts, Y. Vermeulen, and H. Vanermen Endoscopic mitral valve repair: Feasible, reproducible, and durable J. Thorac. Cardiovasc. Surg., February 1, 2003; 125(2): 273 - 282. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
E. A. Hessel II and L. H. Edmunds Jr. Extracorporeal Circulation: Perfusion Systems Card. Surg. Adult, January 1, 2003; 2(2003): 317 - 338. [Full Text]
|
|
|
|
 |
|
 S. C Stoica, S. R Craig, C. J Sinclair, and C. Campanella Heartport Endoclamp for Complex Cardiac Repairs With Total Circulatory Arrest Asian Cardiovasc Thorac Ann, December 1, 2002; 10(4): 376 - 377. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. T. Cheung and C. W. Hogue Jr Ann. Thorac. Surg., February 1, 2000; 69(2): 489 - 490. [Full Text] [PDF]
|
|
|
|
|
|
L. C. Siegel Port-Access Cardiac Surgery: Anesthetic Techniques, Equipment, Applications, Experience, and Outcomes Seminars in Cardiothoracic and Vascular Anesthesia, July 1, 1999; 3(2): 74 - 84. [Abstract] [PDF]
|
|
|
|
|
|
L. K. Han, E. Jacobsohn, and S. Aronson Intraoperative Echocardiography for the Patient Undergoing Minimally Invasive Heart Surgery Seminars in Cardiothoracic and Vascular Anesthesia, July 1, 1999; 3(2): 98 - 108. [Abstract] [PDF]
|
|
|
|
|
|
C. W. Hogue JR, B. Barzilai, and V. G. Davila-Roman Stroke Reduction: Diagnosis and Management of the Atherosclerotic Ascending Aorta During Cardiac Surgery Seminars in Cardiothoracic and Vascular Anesthesia, March 1, 1999; 3(1): 17 - 24. [Abstract] [PDF]
|
|
|
|
|
|
I. M. Plotkin, C. D. Collard, S. F. Aranki, R. J. Rizzo, and S. K. Shernan Percutaneous coronary sinus cannulation guided by transesophageal echocardiography Ann. Thorac. Surg., December 1, 1998; 66(6): 2085 - 2087. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. C. Siegel Endovascular Cardiopulmonary Bypass for Port-Access Minimally Invasive Cardiac Surgery Seminars in Cardiothoracic and Vascular Anesthesia, November 1, 1998; 2(4): 294 - 301. [Abstract] [PDF]
|
|
|
|
 |
|
 W. S Peters, J. I Fann, T. A Burdon, and M. F Pompili Port-access cardiac surgery: a system analysis Perfusion, July 1, 1998; 13(4): 253 - 258. [PDF]
|
|
|
|
|
|
J. Hultman Anaesthesia and monitoring for minimally invasive cardiac surgery with special reference to minimally invasive direct coronary artery bypass surgery Perfusion, July 1, 1998; 13(4): 259 - 264. [PDF]
|
|
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||