Pericardial Suspension to Prevent Encroachment of Emphysematous by djd18436

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LETTER TO THE EDITOR



Pericardial Suspension to Prevent
Encroachment of Emphysematous
Lungs in Cardiac Surgery
Oon C. Ooi, A.F.R.C.S., Robert Grignani, I.B., and Eugene K.W. Sim, F.R.C.S.
Department of Cardiac, Thoracic and Vascular Surgery, The Heart Institute,
National Healthcare Group, Singapore

   Dear Editor,                                                         buttresses, the pericardial edge on the right side was
   Air trapping in emphysematous lungs may result in                    approximated to the posterior surface and lateral edge
the lungs compressing the heart as an unusual compli-                   to the lateral border of the right hemisternum to re-
cation following cardiac surgery. This may cause hemo-                  strain the emphysematous right lung from encroach-
dynamic compromise following approximation of the                       ing into the mediastinal space (Fig. 1B). Thereafter, the
two hemisternii and not allow the chest to be closed.                   sternum was closed uneventfully. This is our second
We describe a method of suspending the pericardial                      successful attempt at using pericardial suspension in a
edge to the posterior surface of the ipsilateral hemis-                 coronary artery bypass grafting case with emphysema-
ternum in preventing an emphysematous lung from                         tous lungs.
exerting a compression effect on the heart in cardiac
surgery.
   A 62-year-old gentleman was brought to the Acci-
dent and Emergency Department with a massive acute
myocardial infarction. Transthoracic echocardiography
showed a left ventricular ejection fraction of 25%.
Emergency coronary catheterization revealed triple-
vessel disease. An intraaortic balloon pump was in-
serted. Emergency on-pump beating-heart coronary
artery bypass grafting was performed using saphenous
vein grafts to the left anterior descending artery, ra-
mus intermedius, and right coronary artery. Intraoper-
ative findings are a dilated heart with poor contractility
and emphysematous lungs. Cardiopulmonary bypass
was terminated uneventfully. While approximating the
sternal edges with sternal wires for chest closure, the
ST-segment in leads II and aVF on the electrocardio-
graph rose significantly accompanied by hypotension
of 80 mmHg systolic pressure. The sternal wires were
divided and the chest reopened. All the saphenous vein
grafts were patent. The anterior borders of the em-
physematous lungs were noted to have crossed the
midline respectively (Fig. 1A) and suspected to be the
cause of the cardiac compromise. Similar electrocardio-
graphic and hemodynamic deterioration recurred when
closure of the sternum was reattempted. The chest
was reopened and the saphenous vein grafts checked
once more. Again, the mediastinal edges of the em-
physematous lungs were found to have crossed the
midline. Using interrupted 2-0 polypropylene sutures
in interrupted horizontal mattress fashion with pledget
                                                                        Figure 1. A. Anterior borders of right and left lung crossing the
Address for correspondence: Eugene KW Sim, Department of Cardiac,       midline. B. The edge of the incised pericardium on the right
Thoracic & Vascular Surgery, National University Hospital, The Heart    side is sutured to the posterior surface of the right hemister-
Institute, National Healthcare Group, 5 Lower Kent Ridge Road, Singa-   num, thus preventing the anterior edge of the right lung from
pore 119074. Fax: +65-6776 6475; e-mail: sursimkw@nus.edu.sg            encroaching into the mediastinum.
J CARD SURG                                                                                  OOI, ET AL.               185
2004;19:184-185                                        PERICARDIAL SUSPENSION FOR EMPHYSEMATOUS LUNGS


   Acute hypotension on sternal reapproximation fol-        ologists, appears to dramatically decrease air trapping
lowing cardiopulmonary bypass may be caused by              and allow closure of the sternotomy without cardiovas-
compromise in coronary perfusion from kinking of            cular instability.
coronary artery bypass grafts, valvular malfunction, or       In this patient with a dilated and poorly contract-
rarely high intrathoracic pressure transmitted by hy-       ing heart, the tamponading effect of air trapping did
perinflated lungs that compromise cardiac function.1-3       not allow closure of the chest. We describe a tech-
The latter, termed “air trapping,” is seen in patients      nique of suspension of the pericardial edge to the
with pulmonary diseases, e.g., chronic obstructive pul-     posterior surface of the ipsilateral hemisternum to
monary disease, with loss of elastic recoil or increased    prevent the lung from infringing on the pericardial
airway resistance and could be attributed to bron-          cavity.
chospasm, bronchiolar mucosal edema, thick inspis-
sated mucus plugging of small airways, and collapsed
                                                                                   REFERENCES
small airways caused by lack of elastic support in the
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   Once air trapping is recognized, therapeutic mea-           mise associated with air trapping following coronary artery
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lieve airway obstruction, reduction in minute venti-           chanical ventilation at rapid frequencies. Anesthesiology
                                                               1972;37:626-633.
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                                                            3. Wallis TW, Robotham JL, Compean R, et al: Mechani-
Minute ventilation should be reduced to the minimum            cal heart-lung interaction with positive end-expiratory pres-
that will maintain adequate pH. Weng and associates1,4         sure. J Appl Physiol 1983;54:1039-1047.
described a method of expiratory flow retard to pro-         4. Weng JT, Smith DE, Graybar GB, et al: Hypotension sec-
mote emptying of peripheral air space units during ex-         ondary to air trapping treated with expiratory flow retard.
halation. This technique, instituted by the anaesthesi-        Anesthesiology 1984;60:350-353.

								
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