Advertisement

Anesthetic Management for Minimally Invasive Cardiac Surgery

  • Julius Hamilton
  • Mark Caridi-Scheible
Chapter

Abstract

The adoption of minimally invasive approaches to cardiac surgery allow for decreased perioperative morbidity without any change to the efficacy of therapy. A growing body of literature has demonstrated decreased ICU length of stay, decreased transfusion requirements and shortened hospitalizations without increases in short or long term mortality when compared to conventional approaches to cardiac surgery. Patient selection is of critical importance as these procedures are paired with increased procedural duration, longer aortic cross clamp times and increased technical difficulty. The use of a minimally invasive approach requires a careful analysis of risks and benefits and deciding factors should include the right procedure by the right surgeon for the right patient, not just a smaller incision.

Keywords

Minimally invasive cardiac surgery (MICS) Totally endoscopic coronary artery bypass (TECAB) Minimally invasive coronary artery bypass (MIDCAB) Mini-aortic valve replacement Minimally invasive mitral valve surgery (MIMVS) 

Introduction

According to the American Heart Association, minimally invasive cardiac surgery is defined as “a small chest wall incision that does not include a full sternotomy” [1]. This description is inclusive of intra-cardiac (i.e., valve replacement, septal defect repair) and extra-cardiac (i.e., coronary bypass) procedures with or without the implementation of cardiopulmonary bypass. The development of minimally invasive approaches has been cultivated by the desire to improve value in cardiac surgery. This value can be achieved by decreasing costs by reducing the time of postoperative recovery and by improving cosmesis while maintaining or improving quality of care. Use of a minimally invasive approach introduces an added level of complexity which requires a skilled perioperative team and appropriate patient selection. For example, studies of minimally invasive cardiac bypass procedures (MIDCAB) have demonstrated lower cost of total care, shorter ICU length of stay [2], and decreased surgical stress [3]; yet this is often paired with longer cross clamp times [4] and the introduction of a prolonged period of one lung ventilation [5] to achieve these endpoints. This interplay of risks and rewards demands that the decision to use a minimally invasive approach be determined by carefully considering the right procedure by the right surgeon for the right patient, rather than just by the length of the incision [6].

Minimally Invasive Coronary Bypass

Minimally invasive approaches to coronary bypass range from the use of a minithoracotomy (MIDCAB) to totally endoscopic coronary artery bypass (TECAB) (see Fig. 6.1). In comparison to intra-cardiac procedures, these extra-cardiac procedures provide an opportunity to avoid use of cardiopulmonary bypass. Studies have demonstrated many benefits of minimally invasive coronary bypass, including reduced ICU length of stay, shorter hospitalization, reduced transfusion requirements, reduced cost of total care [2], less surgical stress [3], less fluid shift, and fewer neuropsychiatric disturbances [7] when compared to CABG with a full sternotomy. The surgical approach often requires utilization of one lung ventilation to improve visualization and because of limited surgical exposure, minimally invasive bypass procedures are often limited to a single bypass. This makes minimally invasive coronary bypass less than ideal for the patient with significant pulmonary disease or multi-vessel coronary disease. When cardiopulmonary bypass is utilized there is typically a longer aortic cross clamp time [4] and longer procedure duration when compared to conventional bypass procedures. A subset of MIDCAB includes the use of robotic assistance (such as the da Vinci® system) to harvest the internal mammary artery from the chest wall.
Fig. 6.1

Various approaches for mini-thoracotomy

Totally endoscopic coronary artery bypass also employs the use of robotic technology and as the name suggests, the procedure is performed from start to finish via endoscopy. This approach requires peripheral cannulation for cardiopulmonary bypass, a pressurized capnothorax, and extensive use of transesophageal echocardiography [8]. Myocardial preservation can be achieved by performing the procedure on a beating heart or with the use of an endoaortic occlusion balloon catheter which functions as the aortic cross clamp as well as a conduit for the delivery of antegrade cardioplegia.

Table 6.1 summarizes important anesthetic considerations for minimally-invasive coronary bypass grafting surgery.
Table 6.1

Anesthetic considerations for minimally-invasive coronary bypass grafting

 

MIDCAB

TECAB

Airway management

One lung ventilation (OLV) utilized

Double lumen endotracheal tube (DLT) or single lumen endotracheal tube (SLT) with bronchial blocker (BB)

Same as MIDCAB

Cannulation strategy

Off pump

± CPB

Peripheral Cannulation (arterial and venous)

Endoaortic occlusion balloon (EAOB) for antegrade cardioplegia

Coronary sinus catheter for retrograde cardioplegia

Monitoring

Standard ASA

Arterial line

CVP

± TEE

± PA catheter

Standard ASA

Arterial line

CVP

TEE (used for correct placement of venous and arterial cannulae when CPB utilized)

Myocardial preservation

N/A

Beating heart

Cardioplegic arrest (antegrade and/or retrograde)

Pain management

Parenteral narcotics

Thoracic epidural

Regional techniques:

Paravertebral block/catheter

Intercostal block

Serratus anterior block/catheter

Same as MIDCAB

Special considerations

Proximal occlusion:

ST changes and new wall motion abnormalities should be expected with proximal occlusion of the left anterior descending coronary artery

Cardiac stabilizer:

Application of a cardiac stabilizer may cause cardiac dysrhythmias or the reduction of cardiac output. Mechanical (IABP), pacer, pressor or inotropic/chronotropic support may be necessary

Limited access:

Defibrillation may be difficult in situations of poor exposure for internal defibrillation. External defibrillator pads should be placed

Same as MIDCAB

Minimally Invasive Aortic Valve Surgery

First described in 1993, a minimally invasive approach to aortic valve replacement (“Mini”-AVR) has grown to a variety of approaches that avoid full sternotomy. These approaches have included port access, infra-axillary [9], parasternal [10], lower hemi-sternotomy [11], and transverse sternotomy [12]. Currently the most popular approaches are upper hemi-sternotomy and right anterior thoracotomy [13]. A meta-analysis performed by Brown et al., found that when compared to a conventional sternotomy, “Mini”-AVR was found to be equally efficacious without increased risk of death or other major complication, but found no other clinical benefits [14]. A subsequent meta-analysis comparing AVR to “Mini”-AVR demonstrated a significant reduction in ICU length of stay [15].

“Mini”-AVR, like other MICS techniques heavily depend on institutional practices and the experience of the perioperative team. Following the learning curve, improvement in outcomes is seen with growing expertise of the perioperative team. This is best displayed by Brigham and Women’s implementation of “Mini”-AVR as routine practice. Following a 5 year learning curve, an analysis of 10 years of surgical outcomes was performed with use of propensity-scored matching. When compared to full sternotomy, the upper hemi-sternotomy (see Fig. 6.2) showed clinical benefits of shorter duration of mechanical ventilation, reduced ICU length of stay, shorter hospitalization, decreased incidence of new onset atrial fibrillation, and decreased transfusion requirements without any difference in short or long-term mortality [16]. Such positive results increase the value in cardiac surgery and strengthen the argument for widespread adoption of “Mini”-AVR.
Fig. 6.2

“Mini”-AVR via upper hemi-sternotomy approach

Use of an upper hemi-sternotomy provides familiarity to the cardiac surgeon, as well as permits for fast conversion to a full sternotomy if necessary. The conversion of hemi-sternotomy to full sternotomy is infrequent and occurs at a rate of 3% [14] Bleeding, ventricular dysfunction, or poor exposure are common causes for conversion and although infrequent, conversion to a full sternotomy has been accompanied by a significant increase in morbidity and mortality [14] Central arterial and venous cannulation can be used with this approach, though some centers prefer peripheral venous cannulation for a more accessible surgical field. Antegrade cardioplegia is utilized for myocardial preservation and direct ostial delivery can be used in the presence of aortic regurgitation.

Table 6.2 summarizes important anesthetic considerations for Mini-AVR.
Table 6.2

Anesthetic considerations for Mini-AVR

 

“Mini” AVR

Airway management

OLV utilized in mini-thoracotomy cases

DLT or SLT with bronchial blocker

SLT for hemi-sternotomy

Cannulation strategy

Typically central aortic and central or peripheral venous cannulation

Monitoring

Standard ASA

Arterial line

CVP

TEE

± PA catheter

Myocardial preservation

Cardioplegic arrest with direct aortic cross clamp

Antegrade cardioplegia

Direct ostial delivery can be utilized in presence of aortic insufficiency

Pain management

Parenteral narcotics

Regional techniques:

Hemisternotomy

Pecs blocks

Mini-thoracotomy

Paravertebral block/catheter

Intercostal block

Serratus anterior block/catheter

Special considerations

Limited access:

Defibrillation may be difficult in situations of poor exposure for internal defibrillation. External defibrillator pads should be placed

Poor exposure is the most common indication for conversion to full sternotomy

Minimally Invasive Mitral Valve Surgery

Popular approaches to minimally invasive mitral valve surgery (MIMVS) include approach via a right mini-thoracotomy (“Mini”-Mitral) and robotic mitral valve surgery. An analysis of the Society of Thoracic Surgeons National Database (STS database) from 2004 to 2008 found shorter hospitalization, fewer blood transfusions, and higher rates of repair rather than replacement when comparing minimally invasive mitral valve surgery to conventional full sternotomy. Unfortunately, these benefits were paired with increased duration of aortic cross clamp time, longer duration of cardiopulmonary bypass, and most prominently, an increased risk of permanent stroke [17]. Stroke and MIMVS has been a very controversial topic in the literature. Modi et al., found no increased risk of stroke in MIMVS versus a conventional approach in their 2008 meta-analysis [18]. The findings in the STS database are likely strongly influenced by their definition of MIMVS, “patients undergoing femoral arterial and femoral or jugular venous cannulation” [18]. Thus, these findings may be most contributed to cannulation strategy rather than surgical incision. In the subgroup analysis of the STS database, the risk of stroke was increased threefold in procedures without aortic cross clamp, such as beating heart or fibrillatory arrest. This data suggests incomplete de-airing as a likely contributor to perioperative stroke. Transesophageal echocardiography should be used to guide de-airing in these cases.

MIMVS via right mini-thoracotomy employs one lung ventilation to improve surgical exposure. Depending on surgeon preference, the mini-thoracotomy can be supplemented by endoscopic access ports with use of capnothorax. In cases employing cardioplegic arrest, use of a direct aortic cross clamp or an endoaortic occlusion balloon (EOAB) can be used to deliver antegrade cardioplegia. Percutaneous endocoronary sinus catheters may also be deployed under TEE guidance to provide retrograde cardioplegia. Additionally, a substitution for a left ventricular vent (traditionally placed in open procedures in a right pulmonary vein) is a pulmonary artery vent placed in a manner similar to a pulmonary artery (PA) catheter which functions to empty the pulmonary circulation (and therefore the left atrium) when on CPB. The pulmonary vent has the ability to measure pulmonary pressures when not being used as an active vent but should be removed from the central venous introducer prior to leaving the operating room. Venous cannulation is often accessed by a femoral venous cannula which requires TEE guidance for appropriate placement. In the 10-year experience of transitioning from conventional mitral valve surgery to routine MIMVS of Glauber et al., presence of severe left ventricular dysfunction, severe chronic obstructive pulmonary disease, pleural adhesions, and endocarditis with abscess involving the mitro-aortic continuity all led to utilization of a full sternotomy instead [19].

Robotic mitral surgery is limited to specialized centers with adequate surgical volume to develop and maintain expertise. Comparative outcome data of robotic mitral valve surgery versus conventional surgery is limited. In the meta-analysis by Cao et al., a mortality benefit was found in favor of robotic mitral surgery, but this analysis was confounded by heterogeneity of the cohorts of the largest study included [20] and its removal from the data analysis erased the mortality benefit [21]. However, individual institutional experiences have shown safe use of robotic mitral valve surgery in the hands of expert surgeons with specialized teams. Murphy et al., demonstrate the safety of their technique along with appropriate discrimination in patient selection. Patients excluded from undergoing robotic mitral valve surgery included those with severe aortoiliac atherosclerosis, right pleural scarring, or significant mitral annular calcification [22]. Conversely, patients presenting for redo operations or whom required tricuspid repair received a mini-thoracotomy approach instead.

The addition of robotic telemanipulation systems provide improved visualization with a three-dimensional console for the operating surgeon as well as increased degrees of movement. The right lung is deflated and one lung ventilation is maintained by capnothorax to provide adequate visualization. Arterial and venous cannulation are accessed peripherally via femoral vessels and often requires the use of vacuum assisted venous drainage. Myocardial preservation is achieved by antegrade cardioplegia delivered by endoaortic occlusion balloon. With TEE guidance, the anesthesiologist places a retrograde coronary sinus catheter to further aid myocardial protection. TEE-guided coronary sinus catheter placement is facilitated by the acquisition of a “deep” 4 chamber view or a modified bicaval view. Appropriate placement of the coronary sinus catheter can be confirmed by injection of dye under fluoroscopy or with inflation of the occlusion balloon with subsequent display of a ventricularized waveform [23] (Fig. 6.3).
Fig. 6.3

Coronary sinus catheter and minimally invasive cardioplegia catheter placement

Table 6.3 summarizes important anesthetic considerations for minimally invasive mitral valve surgery.
Table 6.3

Anesthetic considerations for minimally invasive mitral valve surgery

 

“Mini” MVR

Robotic MVR

Airway management

OLV

DLT or SLT with bronchial blocker

Same as mini MVR

Cannulation strategy

Central or peripheral cannulation

Peripheral cannulation

Monitoring

Standard ASA

Arterial line

CVP

TEE

PA catheter or PA vent

Standard ASA

Bilateral radial arterial lines

CVP

TEE

PA catheter or PA vent

Myocardial preservation

Cardioplegic arrest with direct aortic cross clamp or EAOB

Possible use of retrograde cardioplegia by coronary sinus catheter

Cardioplegic arrest with antegrade cardioplegia, retrograde cardioplegia

Antegrade cardioplegia by EAOB

Retrograde cardioplegia by coronary sinus catheter

Pain management

Parenteral narcotics

Regional techniques:

Paravertebral block/catheter

Intercostal block

Serratus anterior block/catheter

Parenteral narcotics

Regional techniques as indicated

Special considerations

Limited access:

Defibrillation may be difficult in situations of poor exposure for internal defibrillation so external defibrillator pads should be placed

Poor exposure is the most common indication for conversion to full sternotomy

Limited access:

Total endoscopic access necessitates placement of external defibrillation pads

TEE guidance:

TEE-guided placement of EAOB and coronary sinus catheter

Patient Selection and Optimization

Appropriate patient selection and optimization of comorbidities is essential to operative success. Many MICS procedures require prolonged one-lung-ventilation with or without capnothorax to increase surgical exposure, thus patients with significant pulmonary disease are poor candidates for this type of approach. One-lung-ventilation can lead to hypercarbia and hypoxemia with resultant increases in right ventricular afterload secondary to an increase in pulmonary vascular resistance [24]. This increase in pulmonary arterial pressure and decrease in cardiac output should be expected.

For the patient with pre-existing pulmonary disease, pulmonary function tests and an arterial blood gas on room air may provide additional information for risk stratification, as patients with resting hypercarbia (PaCO2 > 50 mmHg) or hypoxemia (PaO2 < 60 mmHg) are poor candidates for prolonged one-lung ventilation [24]. Smoking cessation should be strongly encouraged for at least 2 weeks prior to surgery. Preoperative bronchodilators should be considered in the patient with known reactive airway disease or a significant smoking history.

Presence of other cardiac lesions can lead to a significant change in the surgical plan and approach, thus perioperative transesophageal echocardiography is essential to appropriate management. For instance, presence of tricuspid regurgitation with tricuspid annular dilation in the patient scheduled for a robotic mitral valve repair will significantly modify the surgical plan with robotic surgery no longer being the ideal approach [21].

When considering approaches requiring peripheral arterial cannulation for cardiopulmonary bypass, the patient with a history of peripheral vascular disease may be at increased risk for distal ischemia. Data suggests use of peripheral arterial cannulation to lead to an increased risk of perioperative stroke [17], giving pause to use of peripheral cannulation in the patient with severe atherosclerotic disease.

Bibliography

  1. 1.
    Rosengart TK, Feldman T, Borger MA, Vassiliades TA, Gillinov AM, Hoercher KJ, et al. Percutaneous and minimally invasive valve procedures: a scientific statement from the American Heart Association Council on Cardiovascular Surgery and Anesthesia, Council on Clinical Cardiology, Functional Genomics and Translational Biology Interdisciplinary Working Group, and Quality of Care and Outcomes Research Interdisciplinary Working Group. Circulation. 2008;117(13):1750–67.CrossRefPubMedPubMedCentralGoogle Scholar
  2. 2.
    Zenati M, Domit TM, Saul M, Gorcsan J, Katz WE, Hudson M, et al. Resource utilization for minimally invasive direct and standard coronary artery bypass grafting. Ann Thorac Surg. 1997;63(6 Suppl):S84–7.CrossRefPubMedPubMedCentralGoogle Scholar
  3. 3.
    Ganapathy S. Anaesthesia for minimally invasive cardiac surgery. Best Pract Res Clin Anaesthesiol. 2002;16(1):63–80.CrossRefPubMedPubMedCentralGoogle Scholar
  4. 4.
    Chaney MA, Durazo-Arvizu RA, Fluder EM, Sawicki KJ, Nikolov MP, Blakeman BP, et al. Port-access minimally invasive cardiac surgery increases surgical complexity, increases operating room time, and facilitates early postoperative hospital discharge. Anesthesiology. 2000;92(6):1637–45.CrossRefPubMedPubMedCentralGoogle Scholar
  5. 5.
    Ganapathy S. Thoracic epidural analgesia offers improved postoperative analgesa following midcab. Second meeting of ISMICS 1999.Google Scholar
  6. 6.
    Mihaljevic T, Gillinov M. Invited commentary. Ann Thorac Surg. 2012;93(5):1468.CrossRefPubMedPubMedCentralGoogle Scholar
  7. 7.
    Murkin JM, Boyd WD, Ganapathy S, Adams SJ, Peterson RC. Beating heart surgery: why expect less central nervous system morbidity? Ann Thorac Surg. 1999;68(4):1498–501.CrossRefPubMedPubMedCentralGoogle Scholar
  8. 8.
    Deshpande SP, Lehr E, Odonkor P, Bonatti JO, Kalangie M, Zimrin DA, et al. Anesthetic management of robotically assisted totally endoscopic coronary artery bypass surgery (TECAB). J Cardiothorac Vasc Anesth. 2013;27(3):586–99.CrossRefPubMedPubMedCentralGoogle Scholar
  9. 9.
    Ito T, Maekawa A, Hoshino S, Hayashi Y. Right infraaxillary thoracotomy for minimally invasive aortic valve replacement. Ann Thorac Surg. 2013;96(2):715–7.CrossRefPubMedGoogle Scholar
  10. 10.
    Cohn LH, Adams DH, Couper GS, Bichell DP, Rosborough DM, Sears SP, et al. Minimally invasive cardiac valve surgery improves patient satisfaction while reducing costs of cardiac valve replacement and repair. Ann Surg. 1997;226(4):421–6; discussion 427–8CrossRefPubMedPubMedCentralGoogle Scholar
  11. 11.
    von Segesser LK, Westaby S, Pomar J, Loisance D, Groscurth P, Turina M. Less invasive aortic valve surgery: rationale and technique. Eur J Cardiothorac Surg. 1999;15(6):781–5.CrossRefGoogle Scholar
  12. 12.
    Moreno-Cabral RJ. Mini-T sternotomy for cardiac operations. J Thorac Cardiovasc Surg. 1997;113(4):810–1.CrossRefPubMedGoogle Scholar
  13. 13.
    Malaisrie SC, Barnhart GR, Farivar RS, Mehall J, Hummel B, Rodriguez E, et al. Current era minimally invasive aortic valve replacement: techniques and practice. J Thorac Cardiovasc Surg. 2014;147(1):6–14.CrossRefPubMedGoogle Scholar
  14. 14.
    Brown ML, McKellar SH, Sundt TM, Schaff HV. Ministernotomy versus conventional sternotomy for aortic valve replacement: a systematic review and meta-analysis. J Thorac Cardiovasc Surg. 2009;137(3):670–679.e5.CrossRefPubMedGoogle Scholar
  15. 15.
    Khoshbin E, Prayaga S, Kinsella J, Sutherland FWH. Mini-sternotomy for aortic valve replacement reduces the length of stay in the cardiac intensive care unit: meta-analysis of randomised controlled trials. BMJ Open. 2011;1(2):e000266.CrossRefPubMedPubMedCentralGoogle Scholar
  16. 16.
    Neely R, et al. Minimally invasive aortic valve replacement versus aortic valve replacement through full sternotomy: the Brigham and Women’s Hospital experience. Ann Cardiothorac Surg. 2015;4(1):38–48. [cited 2017 Feb 13]. http://www.annalscts.com/article/view/5084/6300.PubMedPubMedCentralGoogle Scholar
  17. 17.
    Gammie JS, Zhao Y, Peterson ED, O’Brien SM, Rankin JS, Griffith BP. Less-invasive mitral valve operations: trends and outcomes from the society of thoracic surgeons adult cardiac surgery database. Ann Thorac Surg. 2010;90(5):1401–10.CrossRefPubMedGoogle Scholar
  18. 18.
    Modi P, Hassan A, Chitwood WR. Minimally invasive mitral valve surgery: a systematic review and meta-analysis. Eur J Cardiothorac Surg. 2008;34(5):943–52.CrossRefPubMedGoogle Scholar
  19. 19.
    Glauber M, Miceli A, Canarutto D, Lio A, Murzi M, Gilmanov D, et al. Early and long-term outcomes of minimally invasive mitral valve surgery through right minithoracotomy: a 10-year experience in 1604 patients. J Cardiothorac Surg. 2015;10:181. [cited 2017 Feb 13]. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4672482/.CrossRefPubMedPubMedCentralGoogle Scholar
  20. 20.
    Stevens L-M, Rodriguez E, Lehr EJ, Kindell LC, Nifong LW, Ferguson TB, et al. Impact of timing and surgical approach on outcomes after mitral valve regurgitation operations. Ann Thorac Surg. 2012;93(5):1462–8.CrossRefPubMedGoogle Scholar
  21. 21.
    Cao C, Wolfenden H, Liou K, Pathan F, Gupta S, Nienaber TA, et al. A meta-analysis of robotic vs. conventional mitral valve surgery. Ann Cardiothorac Surg. 2015;4(4):305–14.PubMedPubMedCentralGoogle Scholar
  22. 22.
    Murphy DA, Miller JS, Langford DA, Snyder AB. Endoscopic robotic mitral valve surgery. J Thorac Cardiovasc Surg. 2006;132(4):776–81.CrossRefPubMedGoogle Scholar
  23. 23.
    Miller GS. Coronary sinus catheter placement in minimally invasive cardiac surgery: tricks, tactics, and tribulations. Lecture presented at Texas; 2017.Google Scholar
  24. 24.
    Cryer HG, Mavroudis C, Yu J, Roberts AM, Cué JI, Richardson JD, et al. Shock, transfusion, and pneumonectomy. Death is due to right heart failure and increased pulmonary vascular resistance. Ann Surg. 1990;212(2):197–201.CrossRefPubMedPubMedCentralGoogle Scholar

Copyright information

© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.Emory University School of Medicine, Emory University HospitalAtlantaUSA
  2. 2.Department of AnesthesiologyEmory University School of MedicineAtlantaUSA

Personalised recommendations