Preoperative prediction of postoperative edema and effusion in pediatric cardiac surgery by altered antigen expression patterns on granulocytes and monocytes

Postoperative edema and effusion (POEE) following cardiopulmonary bypass (CPB) surgery in children retards recovery and may aggravate postpericardiotomy (PPS), capillary leak syndrome (CLS), or multiorgan failure (MOF). Compared with complication-free children, POEE affected children have different preoperative serum levels of circulating cytokines and adhesion molecules. These levels may be used preoperatively to assess POEE, but their determination is time consuming, costly, and a substantial blood volume is required. Altered serum levels of cytokines and adhesion molecules also may be reflected in altered antigen expression on circulating blood leukocytes. The predictive potential of flow cytometric (FCM) leukocyte immunophenotyping was explored as a sensitive and fast method that required small blood samples. Blood samples taken 24 h preoperatively from 49 patients (3-18 years old) were stained with monoclonal antibodies for adhesion molecules (ICAM-1, LFA-1, Mac-1) or constitutive/activation markers (CD4, CD14, CD16, CD25, CD54, CD69, HLA-DR) and measured on a microbead calibrated FCM. Neutrophils, monocytes, and eosinophils from POEE patients express higher preoperative levels of LFA-1, monocytes, HLA-DR, and other activation markers (all P < 0.03). Over 89% of the patients were classified correctly by using two discriminant analysis methods (sensitivity, >76%; specificity, >86%; positive prediction, >80%; negative prediction, >83%). Granulocytes and monocytes of postoperative POEE patients exhibit significant preoperative immune activation, suggesting an increased risk for patients with atopic/allergic predisposition. Surgical trauma and CPB cause additional immune activation, leading to POEE by a summative response. Most patients at risk for POEE can be identified preoperatively by using data pattern analysis on FCM-derived parameters.

Low degree of activation of circulating neutrophils determined by flow cytometry during cardiac surgery with cardiopulmonary bypass

BACKGROUND

Enhanced expression of adhesion molecules LFA-1 (CD11a/CD18) and Mac-1 (CD11b/CD18) following cardiac surgery with cardiopulmonary bypass (CPB) is held responsible for postoperative complications. Surface expression of these molecules, intracellular pH (pH(i)), and oxidative burst capacity was analyzed to test for neutrophil activation during pediatric cardiac surgery.

METHODS

Blood samples were drawn from 36 patients (age: 3--16 years) 24 h preoperatively, after onset of anesthesia, after connection to CPB (CPB1, before and after passing CPB, n = 15), at reperfusion (CPB2), and up to 7 days postoperatively. Cells adhering to CPB filters were isolated (n = 11). Antigen expression, pH(i), and oxidative burst capacity on neutrophils was analyzed by flow cytometry.

RESULTS

During surgery, oxidative burst capacity was at low level with a mild increase only 1 day after surgery. pH(i) was decreased throughout the surgery. Surgery induced more than 36% decrease of LFA-1 and Mac-1 expression (P < 0.03). Up to postoperative day 7, no increase of antigen expression above baseline was found. Neutrophils isolated from filters of the CPB had increased LFA-1 and Mac-1 expression (all P < 0.05). Integrin expression on neutrophils passing the CPB at CPB1 was decreased (P < 0.05).

CONCLUSION

Reduced adhesion molecule expression on neutrophils may be due to selective filtration of highly adhesive cells. This, in combination with low-level oxidative burst capacity, induced by immunosuppressive cytokines (e.g., interleukin-10), reduced the neutrophil activity. Our data indicate that increased activity of circulating neutrophils cannot exclusively be held responsible for postoperative complications after surgery with CPB.

Anatomical reconstruction of aorta and pulmonary trunk in patients with an aortopulmonary window

We report a modified technique for repair of aortopulmonary window in which a native pulmonary artery flap is created and the aortopulmonary window is completely divided. The pulmonary artery flap is used to reconstruct the ascending aorta, and the defect in the pulmonary trunk is closed with an autologous pericardial patch. This repair avoids the use of a fabric patch with its inherent disadvantages and allows anatomical reconstruction of both the ascending aorta and the pulmonary trunk with low risk of early or late distortion of the aortic and pulmonary root structures.

Urgency of operation in infracardiac total anomalous pulmonary venous connection

BACKGROUND

Because the tendency for pulmonary venous obstruction in the infracardiac type of total anomalous pulmonary venous connection may be partially dependent on the connection of the descending vein to the portal vein, the inferior vena cava, or one of their tributary vessels, we reviewed our surgical experience with various subtypes of infracardiac total anomalous pulmonary venous connection.

METHODS

The urgency of operation in 4 neonates with infracardiac total anomalous pulmonary venous connection was reviewed.

RESULTS

Two patients with pulmonary venous obstruction in whom the descending vein connected to the portal vein were operated on immediately with successful outcome. One patient who had become critically ill after the ductus venosus had closed died before operation could be undertaken. One patient in whom the descending vein connected to the left hepatic vein was operated on electively with successful outcome.

CONCLUSIONS

In hemodynamically stable patients with no clinical or echocardiographic signs of pulmonary venous obstruction, some form of differentiation with regard to urgency of operation may be appropriate. When the descending vein connects to the inferior vena cava or a hepatic vein, the operation may be performed on a semi-elective basis. In contrast, when the descending vein connects to the portal vein or the ductus venosus, operation should generally not be delayed because of the high likelihood of obstruction.

Pulmonary artery sling: reimplantation versus antetracheal translocation

BACKGROUND

We compared two repair techniques for pulmonary artery sling. The first comprised detachment of the aberrant left pulmonary artery from the right pulmonary artery and its implantation into the main pulmonary artery, and the second, translocation of the left pulmonary artery anterior to the trachea (without implanting it into the main pulmonary artery), resection of tracheal stenosis, and end-to-end reconstruction of the trachea.

METHODS

Five symptomatic infants (3 boys and 2 girls; median age 5 months; range, 3 weeks to 11 months) with pulmonary artery sling were operated on through a median sternotomy with aid of cardiopulmonary bypass. In 3 patients, the left pulmonary artery was transected from the right pulmonary artery and implanted into the main pulmonary artery. In addition, the anterior trachea was augmented with a pericardial patch (n = 2). In the remaining 2 patients, associated tracheal stenosis was resected, the left pulmonary artery was translocated anterior to the trachea, and the trachea was reconstructed.

RESULTS

All 5 infants survived the operation. The 3 patients in whom the left pulmonary artery was implanted into the main pulmonary artery had an uncomplicated postoperative course. All 3 patients, at a follow-up of 10 months to 7.9 years, were free of symptoms; the left pulmonary artery was documented to be widely patent. The remaining 2 patients in whom the left pulmonary artery was translocated anterior to the trachea could not be extubated. In both patients the distal trachea was compressed anteriorly by the left pulmonary artery. One of these patients died at 1 week postoperatively secondary to tracheal dehiscence. In the other patient, the left pulmonary artery was implanted into the main pulmonary artery with good result; at a follow-up of 3.9 years, mild residual stridor has persisted.

CONCLUSIONS

In pulmonary artery sling, implantation of the aberrant left pulmonary artery into the main pulmonary artery, if necessary combined with anterior tracheoplasty, reliably eliminates tracheal and esophageal compression and maintains antegrade flow into the left pulmonary artery. Translocation of the left pulmonary artery anterior to the trachea without implanting it into the main pulmonary artery is not favored because that might result in anterior compression of the trachea. In addition, we are concerned about growth of the circumferential tracheal anastomosis in neonates and infants.

Early repair of coarctation of the aorta

BACKGROUND

Repair of coarctation of the aorta with hypoplasia and elongation of the proximal aortic arch is a technically demanding procedure with a substantial rate of recurrent stenosis at the coarctation repair site. In addition, a high incidence of hypertension has been reported in patients who underwent repair beyond infancy.

PATIENTS AND METHODS

Between January 1991 and June 1997, 52 patients (34 neonates and 18 infants with a median age of 37 days; range 2 days to 8 months) with a mean peak systolic upper to lower extremity resting gradient of 33.5 +/- 18.9 mmHg underwent repair of aortic coarctation. The echocardiographically measured median diameter of the aortic arch immediately distal to the innominate artery was 5.4 mm (range 4.0 to 8.1 mm). Eight patients (15%) were considered hypertensive. In 41 patients, through a left thoracotomy, an end-to-side anastomosis was constructed between the descending aorta and the undersurface of the proximal aortic arch. In 12 of these patients (who all had a hypoplastic and elongated aortic arch) this procedure was preceded by the construction of an extended side-to-side left carotid-subclavian arterioplasty. The remaining 11 patients, all with hypoplasia of the aortic arch, had concomitant complete repair of intracardiac anomalies through a median sternotomy. In 8 of these patients, in addition to anastomosis of the descending aorta to the undersurface of the proximal aortic arch, the ascending aorta and aortic arch were augmented with a pulmonary homograft patch.

RESULTS

One neonate with associated Shone's syndrome died (2%) on the first postoperative day. There was no late mortality. Early postoperative complications included recurrent laryngeal nerve injury in 1 patient and prolonged chest tube drainage in 4 patients. At a median follow-up of 55 months (range 15 to 92 months), only 3 patients (5. 7%) developed a recurrent stenosis at the coarctation repair site. The remaining 48 patients are free of recurrent stenosis by echocardiography and clinical examination. None of the patients had systemic hypertension.

CONCLUSIONS

1. Coarctation repair consisting of resection of all ductal tissue with end-to-side anastomosis of the descending aorta to the undersurface of the (proximal) aortic arch, if necessary combined with a side-to side left carotid-subclavian arterioplasty, may lead to excellent results. 2. This technique can be applied with low mortality and morbidity via a left thoracotomy if the proximal aortic arch is at least 5 mm in diameter. 3. In view of the low mortality, the low incidence of restenosis at the coarctation repair site, and the absence of substantial morbidity including the development of hypertension, we advocate repair of aortic coarctation at neonatal age or in early infancy to avoid the detrimental sequelae of delayed repair of coarctation, in particular hypertension.

Operative treatment of hypertrophic obstructive cardiomyopathy and aortic valve disease in infants

BACKGROUND

The indications for operative intervention for symptomatic hypertrophic obstructive cardiomyopathy (HOCM) in infancy and childhood are not well defined because of the rarity of the lesion. The traditional surgical procedure consists of septal myectomy. In an attempt to further improve the outcome of HOCM associated with concentric left ventricular hypertrophy and aortic valve disease in infancy, we have combined resection of the left ventricular septum and free wall with a Ross-Konno procedure.

METHODS

Three infants (aged 3, 4, and 10 months) with HOCM (left ventricular aortic gradients of 75, 95, and 110 mmHg), associated concentric left ventricular hypertrophy, and valvar aortic stenosis (n = 1) or combined valvar aortic stenosis and regurgitation (n = 2) underwent extensive resection of fibroelastosis and subendocardial myocardium of the left ventricular septum and free wall in combination with a Ross-Konno operation. All three patients had marked systolic anterior motion of the mitral valve. The length of the incision into the ventricular septum was 1.8, 2.0, and 2.3 cm.

RESULTS

In all three patients this procedure resulted in a marked reduction of width of the left ventricular septum (median 9 mm vs 14 mm preoperatively) and the left ventricular posterior free wall (median 8 mm vs 12 mm preoperatively) and an almost twofold increase of the left ventricular end-diastolic volume (median 13.5 cm3 vs 7.0 cm3 preoperatively). The neo-aortic valve functioned normally. Systolic anterior motion of the anterior leaflet of the mitral valve had completely resolved in two patients and had markedly regressed in the remaining patient. At follow-up of 15, 17, and 26 months, two patients had absence of a left ventricular outflow tract gradient and the third patient had a residual sub-valvar gradient of 15 mmHg.

CONCLUSIONS

The reported procedure may be a valuable technique in severe forms of hypertrophic cardiomyopathy associated with aortic valve disease. The operation results in enlargement of the left ventricular stroke volume and improvement of the left ventricular diastolic function, restores aortic valve anatomy and function, and abolishes or decreases systolic anterior motion of the mitral valve.

Complement activation, cytokines, and adhesion molecules in children undergoing cardiac surgery with or without cardiopulmonary bypass

The effect of cardiopulmonary bypass (CPB) on various blood parameters in children undergoing major cardiovascular surgery was investigated in a prospective clinical study. Blood samples of children with CPB (CPB group, n = 18) or without CPB (control, n = 12) were collected before, during, and after surgery. The concentration of routine laboratory parameters, components of the complement system (C3, C4, C5, C1 inhibitor, total hemolytic complement, C3d, and C5a), circulating interleukins (IL-6 and IL-8) and soluble adhesion molecules (sICAM-1 and sE-selectin) were determined. In both groups of patients the serum concentrations of C3, C4, C5, and C1 inhibitor were significantly affected by the treatments (p < 0.001), decreased immediately after onset of anesthesia, were minimal during surgery, and increased thereafter. No significant differences in the kinetics of these parameters were detectable between CPB and control group. In the CPB group the activation of the alternative pathway (increased C3d) was found to be a specific response (p = 0.005), but also in the control group C3d and C5a concentration increased significantly (p < 0.022), indicating complement activation. None of the effects that would be expected after activation of the complement system were specific for the CPB group. In both groups the serum levels of IL-6 increased dramatically during and/or after surgery (p = 0.001), and IL-8 was detectable after surgery in 10/12 control patients. The concentration of sICAM-1 and sE-selectin decreased during surgery (p < 0.04) and later did not increase above baseline. Our data suggest that increased serum levels of inflammation mediators and increased consumption of complement and adhesion molecules occur during cardiovascular surgery. Although complement activation and ICAM-1 consumption are more pronounced in the CPB patients, none of these changes occurs exclusively in the CPB group. We conclude, therefore, that these changes are the combined effect of anesthesia, surgical trauma, and endothelial lesions. Additional, undefined CPB-induced reactions may also contribute the postoperative morbidity.

Conversion of atriopulmonary or lateral atrial tunnel cavopulmonary anastomosis to extracardiac conduit Fontan modification

OBJECTIVE

Obstruction of the atriopulmonary anastomosis or the lateral atrial tunnel cavopulmonary anastomosis in the Fontan circulation for univentricular physiology may result in dilation of the right atrium or the right atrial free wall that is incorporated in the lateral atrial tunnel, respectively. Secondary detrimental sequelae may consist of supraventricular dysrhythmias, thromboembolism, right pulmonary vein compression, pleural effusions, and protein-losing enteropathy. Conversion of these Fontan connections to an extracardiac conduit cavopulmonary anastomosis may improve central systemic venous flow patterns and provide clinical improvement in these patients.

METHODS

Eighteen patients (7-40 years old) with atriopulmonary anastomosis (n = 15) or obstructed lateral atrial tunnel cavopulmonary anastomosis (n = 3) presented at 5.7 +/- 3.9 years with moderate to severe right atrial dilation (n = 15), Fontan pathway obstruction (n = 12), atrial dysrhythmia (n = 13), pleural effusion (n = 8), right atrial thrombus (n = 3), right pulmonary vein compression (n = 3), and protein-losing enteropathy (n = 3). All patients underwent conversion to an extracardiac conduit cavopulmonary anastomosis.

RESULTS

Two of the three patients with protein-losing enteropathy died (2/18; 11%) on the 30th and 52nd postoperative days. At a mean follow-up of 19 months, the remaining 16 patients had marked (n = 11) or moderate (n = 5) clinical improvement. The SaO2 improved from 90.7 +/- 5.3% to 96.0 +/- 4.1%. None of the patients had obstruction in the systemic venous pathway. In the 13 surviving patients with previous atriopulmonary anastomosis there was a drastic reduction in right atrial size. Four of 13 patients with atrial dysrhythmias converted to sinus rhythm. The right pulmonary vein compression as present in three patients resolved after conversion. Pleural effusions disappeared in four patients.

CONCLUSIONS

Conversion to an extracardiac cavopulmonary connection may lead to clinical improvement in patients with atriopulmonary or lateral atrial tunnel Fontan connection associated with specific target conditions such as obstruction, pulmonary vein compression, right atrial enlargement, atrial dysrhythmia, or atrial thrombus. The conversion operation should not be unduly delayed to prevent irreversible deterioration of clinical status with chronic rhythm disturbances or protein-losing enteropathy. The benefit of the conversion operation is questionable in patients with poor clinical condition and protein-losing enteropathy.

Changes of leukocyte subsets in coronary artery bypass surgery: cardiopulmonary bypass versus 'off-pump' techniques

BACKGROUND

The use of cardiopulmonary bypass (CPB) in coronary bypass grafting is associated with a generalized inflammatory response. This negative impact of CPB may be avoided by using new surgical techniques recently introduced to perform coronary bypass grafting 'off-pump', i.e. without CPB.

METHODS

Since the specific effects of CPB on the immunorelevant cells have still not been fully investigated, we measured the changes in leukocyte subsets of the circulating blood in patients who underwent coronary bypass surgery with a conventional sternotomy approach and CPB (group A, n = 10), in patients who underwent the same surgical procedure but without CPB (group B, n = 10), and in patients who underwent a minimally invasively performed single bypass to the left anterior descending artery (LAD) (group C, n = 10).

RESULTS

Leukocyte subsets showed a similar change during and after coronary bypass grafting in all three groups. The total number of leukocytes was increased soon after reperfusion in the CPB group. A similar but delayed increase was observed in both off-pump groups. Changes in lymphocyte subsets and T-lymphocyte subsets were similar in all three groups, with a drop of lymphocytes during the first 24 postoperative hours mainly caused by a drop of T4-helper cells.

CONCLUSION

The results indicate a reaction of the leukocyte subsets to coronary bypass surgery which is more related to the surgical trauma in general than to CPB in particular.

Extracardiac repair versus intracardiac baffle repair of complex unroofed coronary sinus

Complex unroofed coronary sinus with a persistent left superior vena cava has as its commonest major associated intracardiac anomaly a partial or complete atrioventricular canal defect. In this clinical setting, biventricular repair with construction of a complex intra-atrial baffle from the pulmonary veins to the mitral valve has a reported mortality rate of as high as 50%. Looking for an improvement, we have carried out an extracardiac repair of the anomalous systemic venous component with atrial septation. In 2 infants (aged 7 and 12 weeks) with unroofed coronary sinus, bilateral superior venae cavae, right isomerism, and complete atrioventricular canal, in addition to patch closure of the ventricular component of the atrioventricular septal defect, a baffle was constructed between the pulmonary veins and the mitral valve. In four subsequent infants (aged 7,10,16, and 20 weeks) with unroofed coronary sinus, bilateral superior venae cavae, complete atrioventricular canal, right isomerism (n = 2), and mild infundibular stenosis (n = 1), repair consisted of end-to-side anastomosis of the left superior vena cava to the right superior vena cava and complete repair of the atrioventricular canal and associated conditions. There was no mortality. The early postoperative course in the two patients with intra-atrial baffle was characterized by increased left-atrial pressure (18 and 20 mm Hg), with varying degrees of pulmonary venous congestion, supraventricular tachycardias, and systemic hypotension. The pulmonary venous congestion increased, so that one patient was successfully converted 10 weeks postoperatively to an extracardiac repair with septation of the atria and the other will probably follow. In the 4 patients with a primary extracardiac repair, the hemodynamic result was excellent, with a median left-atrial pressure of 11 mm Hg on the first postoperative day. At a median follow-up of 12 months, all 5 patients with an extracardiac repair are clinically well with widely patent anastomoses between the left and right superior venae cavae. The extracardiac repair technique for complex unroofed coronary sinus, as opposed to the intra-atrial baffle repair, avoids creation of a small and low-compliance left-atrial compartment with the potential for development of pulmonary venous congestion.

Repair of aortico-right ventricular tunnel

Aortico-right ventricular tunnel was successfully corrected in a 15-month-old child. Both the aortic and right ventricular openings were closed with pledgeted sutures. The coronary artery anatomy was normal. At 12-month follow-up the patient is in excellent clinical condition. Before surgical intervention for aortico-right ventricular tunnel is undertaken, every effort should be made to diagnose the coronary artery anatomy, because failure to do so in the case of aberrant origin of a coronary artery may prevent successful surgical correction.

Modified repair of mixed anomalous pulmonary venous connection

A modified repair technique is reported for mixed total or partial anomalous pulmonary venous connection with the right superior pulmonary vein connecting to the superior vena cava, the right inferior pulmonary vein to the right atrium or left atrium, and the left pulmonary veins to the coronary sinus. The superior vena cava is transected above the highest right superior pulmonary vein, its cephalad end is anastomosed to the right atrial appendage, and a pericardial baffle is constructed between the cardiac ostium of the superior vena cava, the ostium of the right inferior pulmonary vein, and the left atrium, including the coronary sinus, which is unroofed. The reported technique may be valuable to avoid pulmonary venous obstruction in complex mixed forms of total or partial anomalous pulmonary venous connection.

Suspension of straddling tricuspid valve chordae into the appropriate ventricle

In 2 children with an inlet ventricular septal defect and straddling chordae tendineae of the septal leaflet of the tricuspid valve to the posteromedial papillary muscle of the mitral valve and to an accessory papillary muscle in the left ventricle, the straddling chordae were excised with a wedge of posteromedial papillary muscle and with the top segment of the accessory papillary muscle, respectively. After patch closure of the ventricular septal defect, the papillary muscle segment with its group of chordae was anchored to the right ventricular septum with resulting competence of the tricuspid valve. In contrast to the traditional repair technique, the reported modification is applicable when the straddling chordae insert into a papillary muscle of the mitral valve. In addition, various disadvantages related to the construction of a complex baffle in the inappropriate ventricle are avoided.

Repair of complex unroofed coronary sinus by anastomosis of left to right superior vena cava

An extracardiac repair technique is described for the anomalously connecting left superior vena cava in complex unroofed coronary sinus syndrome. In this technique, the left superior vena cava is divided distally and is anastomosed to the right superior vena cava in an end-to-side fashion; in addition, the intracardiac anomalies are corrected. The main advantage of this technique consists of avoidance of the various disadvantages of construction of a complex intraatrial baffle.

[Initial experience with monoclonal antibodies in therapy of life threatening nosocomial infections in the neonatal period]

Despite the use of modern broad spectrum antibiotics nosocomial infections are an unsolved problem, especially in the field of neonatal intensive care (preterm babies and newborns). In patients with septic shock human monoclonal antibodies in combination with appropriate antibiotics have proven effective and compatible for children older than one year. So far, there have been no reports in the literature on the application of such kind of antiendotoxin immunotherapy for pre-term babies and newborns. We describe the effectiveness of monoclonal antibodies in two newborns. Already 12 respectively 16 hours after application of the human monoclonal IgM antibodies (Centoxin) and appropriate antibiotics, the clinical condition of our patients stabilized. Consecutively further clinical symptoms improved rapidly.

[Leukocyte function in patients with hyperthyroidism]

In 20 patients with hyperthyroidism the behaviour of the agglomeration of leucocytes as well as of the adhesivity before and after the methimazol therapy was investigated. The agglomeration of leucocytes was directly inhibited neither by the overfunction of the thyroid gland nor by methimazol. By means of a stimulation test an undisturbed ability of leucocytic activation in hyperthyroidism could be proved. The adhesivity at the glass slide, however, was slightly restricted in untreated hyperthyroidism. It normalized under thyrostatic therapy.