Duncan R. Walker

Noncardiogenic pulmonary edema complicating lung resection

Postresectional pulmonary edema is a rare but potentially fatal complication of thoracic operations. In a retrospective study of 402 lung resections we have identified 11 cases of postresectional, noncardiogenic pulmonary edema. We have analyzed the individual data to test recognized hypotheses regarding this condition. Pulmonary edema occurred in 5.1% of right pneumonectomies, 4.0% of left pneumonectomies, and 1% of all lobectomies. In 2 patients the symptoms occurred immediately after operation; in the other 9 the mean interval to diagnosis was 43.4 hours. All 11 patients were in a positive fluid balance in the first 24 hours after operation (mean, 20.8 +/- 9.1 mL/kg). However, there was no significant difference between this value and the respective values for control groups of 20 patients having pneumonectomies and 20 patients having lobectomies in whom pulmonary edema did not develop. Our findings differ from other reported series in that perioperative fluid overload was not found to be a significant contributory factor in the development of postresectional pulmonary edema. We discuss other possible mechanisms for this phenomenon.

Calcification of Glutaraldehyde-Preserved Porcine and Bovine Xenograft Valves in Young Children

Eight children (mean age, 7.6 years) had xenograft prosthetic valves inserted. All developed evidence of prosthetic valve obstruction requiring reoperation 18 to 55 months after insertion (mean, 32 months). At operation, all the valves were found to be heavily calcified. There were two perioperative deaths. Of two patients who had a second xenograft valve inserted, one died suddenly 12 months later. Gross calcification of the xenograft was found at postmortem examination. The other patient had evidence of mild xenograft calcification at follow-up 19 months postoperatively. Four of the ten calcified xenograft valves were of bovine origin (Ionescu-Shiley type); in these the calcific obstruction occurred significantly earlier than in the six porcine (Hancock) valves.

Magnesium flux caused by coronary artery bypass operation: Three patterns of deficiency

We undertook a study to evaluate the patterns of magnesium deficiency that may develop during and following coronary artery bypass operation without cardioplegia. In 18 patients intraoperative measurements of plasma magnesium and potassium concentrations and measurements of cardiac and skeletal muscle content of these ions were taken. The changes in plasma concentrations and excretion were evaluated postoperatively. Hemodilution at initiation of cardiopulmonary bypass caused a 17.3% decrease in plasma magnesium concentration (p < 0.01), which persisted until the first postoperative day. By the fifth postoperative day the level was 19.5% greater than the preoperative value. Urinary excretion of magnesium reflected changes in plasma magnesium concentration. Cardiac muscle content of magnesium decreased by 13.3%. Plasma potassium concentration was elevated by hemodilution (p < 0.01), and muscle potassium was not depleted. We conclude that three patterns of magnesium depletion occur: hemodilution, intraoperative cellular depletion, and postoperative cellular depletion. The findings support the need for magnesium supplementation during and after cardiac operation.

Lipoma of the mitral valve and papillary muscle

An asymptomatic girl presented at age 2 years, with signs of MR. The electrocardiogram showed left ventricular (LV) hypertrophy, and a chest radiogram showed an enlarged left atrium but was otherwise normal. At 4 years, cardiac catheterization showed a mean pulmonary capillary wedge pressure of 14 mm Hg with a V wave of 27 mm Hg. The LV cineangiocardiogram showed free MR . No filling defect was seen in the left ventricle, left atrium, or region of the mitral valve. The patient remained asymptomatic; hemoglobin, white blood cell count, and erythrocyte sedimentation rate were normal . Echocardiography, performed when the patient was 14 years of age with a mechanical sector scanner (Advanced Technical Laboratories, Seattle, Washington, 5 MHz probe), showed a dense mass of echoes arising from the posterior mitral leaflet ; it extended anteriorly toward the free edge of the anterior leaflet, from which it was separated by an echo-free space (Fig . 1). The 2-dimensional echocardiogram revealed the presence of 2 tumors, I in the posterior mitral leaflet and I in the posterior papillary muscle (Fig . 2) . The mitral valve was explored when the patient was 16 years old. The posterior cusp was replaced by a hemispherMay 1, 1983 THE AMERICAN JOURNAL OF CARDIOLOGY Volume 51 1459

Magnesium flux during and after open heart operations in children

Hypomagnesemia and depletion of the bodys magnesium stores is known to be associated with an increased incidence of both cardiac arrhythmias and neurological irritability. In a two-part prospective study we have evaluated whether magnesium deficiency is a significant occurrence in children treated in the intensive care unit after open heart operations, and subsequently have sought to identify how intraoperative metabolic changes were related to the resultant findings. In 41 children studied after operation the plasma magnesium concentration showed a significant decrease from 0.92 mmol/L (10th to 90th centile, 0.71 to 1.15 mmol/L) immediately after operation to 0.77 mmol/L (0.65 to 0.91 mmol/L) on the following morning. The subsequent change in grouped values was not significant but 14 (34.2%) and 7 (17.1%) possessed values of less than 0.7 mmol/L and 0.6 mmol/L, respectively. The occurrence of cardiac arrhythmias was not statistically related to the occurrence of hypomagnesemia. In 21 children perioperative changes in extracellular and tissue magnesium, potassium, and calcium content were measured. It was found that hemodilution with a prime low in magnesium caused a reduction from a median of 0.81 mmol/L to 0.61 mmol/L (p < 0.01). Plasma potassium level, however, was elevated from 3.7 mmol/L to 4.15 mmol/L (p < 0.05) and the ionized calcium content from 1.17 mmol/L (1.07 to 1.25 mmol/L) to 1.49 mmol/L (1.25 to 2.56 mmol/L) (p = 0.0009). The myocardial content of magnesium did not change significantly but skeletal muscle content was depleted from 6.75 mumol/g (2.85 to 8.35 mumol/g) to 5.65 mumol/g (2.45 to 7.2 mumol/g) (p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Multiple pulmonary microemboli complicating pneumonectomy.

Pulmonary embolism is widely recognized to complicate abdominal and lower limb orthopedic surgical procedures, but in comparison, it is seldom recognized to hamper the postoperative progress of patients after thoracic operations. We present 4 patients in whom multiple pulmonary emboli developed after pneumonectomy, 2 of whom were treated successfully. We discuss the mostly atypical presentation and the physiological and clinical consequences, and also suggest a mode of management.

Operative insertion of a transvenous left atrial pressure monitoring line

We describe a technique for the insertion of a left atrial pressure monitoring line during open heart operations in infants. The procedure requires central venous cannulation with a long catheter, followed by intraoperative placement of the catheter tip through the interatrial septum into the left atrium. The technique has been used successfully in 35 infants.

The Killingbeck pediatric lung retractor

A new series of lung retractors has been designed for use in patients ranging from premature infants to large children. Their unique shape, low profile, and light weight affords excellent exposure with a minimum of trauma to tissues.