Los Angeles Ballroom

7. Psychomotoric and Intellectual Development after Deep Hypothermia and Cardiac Arrest in Early Infancy

B. J. MESSMER*, U. SCHALLBERGER* and S. SENNING,

Zurich, Switzerland

The uncertainty about the late effects of deep hypothermia and cardiac arrest remains a persistent threat when the method is used for total correction of congenital heart disease in early infancy.

Total correction of VSD, TGA, TAPVR and AS has been achieved in selected cases mainly during the years 1968 and 1969 with surface induced hypothermia. Cardiac arrest varied from a minimum of eight to a maximum of 61 minutes at temperatures between 20°C and 25°C in eleven nonselected patients who could be studied three to ten years after surgery. Their medium age at operation was 3 months (1 week to 23 months). Late evaluation consisted of the actual cardiac and physical status. Special psychologic test series were employed to define the psychomotoric and intellectual status of these children.

The operative result was good in all children. The verbal and the nonverbal intelligence expressed by the corresponding I.Q. showed that eight children are within the normal range or even above while three children are below. A simultaneous comparison to a matched group of children who had cardiovascular surgery during early infancy under normo- or slight hypothermia has not shown any significant difference in intellectual behavior.

Deep hypothermia and cardiac arrest thus does not seem to have negative influence to the late psychomotoric and intellectual development. A correlation, however, seems to exist between age and body weight at the time of operation and intellectual development. The older the infant is at the time of surgery the smaller will be the chances of normal intellectual development.

*By invitation

8. Acute Clinical Hypocalcemic Myocardial Depression During Rapid Blood Transfusion and Postoperative Hemodialysis: A Preventable Complication

GORDON N. OLINGER*, CHRISTOF HOTTENROTT*,

DONALD G. MULDER, JAMES V. MALONEY, JR. and

GERALD D. BUCKBERG, Los Angeles, California and Heidelberg, Germany

Despite experimental evidence that acute myocardial depression resulting from rapid transfusion of ACD blood (citrate binds ionic calcium) is avoidable by simultaneous calcium administration, most hypovolemic patients receive calcium either after transfusion or not at all. Similar iatrogenic hypocalcemic myocardial depression occurs in normovolemic patients dialyzed for acute uremia secondary to low postoperative cardiac output when ACD blood prime is used at high initial flow rates (350 cc/min) and when dialysis is performed against low calcium dialysate (2.5mEq/l).

This study tests the hypotheses that 1) rapid blood transfusion (ACD or CPD) is safe if calcium is given simultaneously, 2) addition of calcium to dialysis heparinized blood prime prevents initial depression, 3) hemodynamic instability during dialysis is prevented when the dialysate is normocalcemic, and 4) depressive effects of ACD and CPD blood are similar.

In 9 hypovolemic but stable patients (pre-cardiopulmonary bypass for coronary revascularization - blood shed during sternotomy but not replaced) equal vol-(500cc) of CPD + heparin blood and of CPD + heparin + calcium blood were transfused at 2cc/kg/min in random order and cardiac output (electromagnetic flow probe), arterial pressure, and left atrial pressure were monitored continuously. Recalcified blood transfusion augmented cardiac work 76%. This normal function curve was depressed markedly by transfusion of non-recalcified blood; there was 42% less cardiac work (P < 0.0005) at a 30% greater left atrial pressure (P < 0.005). In 10 post-cardiac surgery dialysis patients conversion to normocalcemic dialysate (4.0mEq/l) and addition of calcium to blood primes prevented cardiac depression and hemodynamic instability.

We conclude 1) acute myocardial depression with CPD blood is similar to ACD blood and is prevented during transfusion of both by simultaneous calcium administration, and 2) hemodialysis in post-cardiac surgery patients is safe if calcium is added to blood prime and dialysis is made normocalcemic.

*By invitation

9. Preoperative Assessment of Esophageal Pathology

ROBERT D. HENDERSON* and F. GRIFFITH PEARSON, Toronto, Canada

Panmural esophagitis results in esophageal thickening and shortening and prevents adequate reduction of a hernia. Twenty patients with panmural esophagitis, treated by Belsey repair, have been followed more than 5 years, 9 remain asymptomatic, 11 have symptomatic reflux and 7 have required further surgery. Belsey also has reported a 45% recurrence rate in this type of patient.

Preoperative recognition of panmural esophagitis allows a planned surgical approach, and the use of a surgical technique designed for the management of an ir-reducable hernia. The ability to predict these changes were studied in 124 patients, who were evaluated by history, radiology, endoscopy and manometry prior to transthoracic hernia repair. The esophagus was inspected at operation to determine the presence of panmural changes. History was of no value in assessment. Radiologically a large and irreducable hernia was associated with panmural changes, but these changes also occurred in the absence of ulceration. Manometric studies allowed accurate prediction of mural changes. Over 90% of patients with pan-mural esophagitis have more than 40% distal disordered motor activity (D.M.A.) and 75% more than 60% D.M.A. Combining these investigative data, an accurate prediction of panmural changes was possible in 90% of the 124 patients.

*By invitation

10. Operative Management of Acid Peptic Esophageal Strictures

LUIS H. TOLEDO-PEREYRA*, GUILLERMO MANIFACIO*,

LYLE D. JOYCE* and EDWARD W. HUMPHREY,

Minneapolis, Minnesota

From 1960 to 1973, 88 patients with an acid-peptic stricture of the esophagus were seen. Of these, 56 patients were treated by dilatation and medical therapy only, while 32, all medical failures, underwent operative therapy followed by esophageal dilatation. In 26 of the 32 patients, esophagitis was described on the endoscopic examination. Sixteen patients had a high gastric acid secretory rate^ and 12 patients also had a history of a duodenal ulcer. Thirteen patients had only a hiatus hernia repair, 10 had a hiatus hernia repair plus a vagotomy and pyloroplasty or a gastric resection without hiatus hernia repair, and 2 had a colon interposition. The most common hernia repair was a Nissen or Belsey type. An average of 4 postoperative dilatations to size 45 French over a period of 2Vi months was required to obtain satisfactory swallowing. Patients that underwent a hiatus hernia repair plus a vagotomy and pyloroplasty had a greater duration of symptoms prior to surgery than did those patients having only a hiatus hernia repair. In addition, 5 patients in the hiatus hernia repair plus vagotomy group had had significant pre-operative bleeding whereas none of the group having only a hiatus hernia repair had bled, yet no postoperative differences were observed between these 2 groups. The initial results (6 months) of all patients undergoing operative therapy were: poor, 6; good to excellent, 26. Of the 26 having an initial satisfactory result, only 2 have had a subsequent recurrence of symptoms and required further dilatation. Most patients with acid-peptic esophageal strictures respond adequately to a hiatus hernia repair plus an acid reducing operation. The necessity for replacing the esophagus in this condition is rare.

INTERMISSION - VISIT EXHIBITS

*By invitation

11. The Effect of Positive End-Expiratory Pressure on Regional Ventilation and Perfusion in the Normal and Injured Primate Lung

JOHN W. HAMMON, JR.*, WALTER G. WOLFE*, JON F. MORAN*,

ROBERT H. JONES* and DAVID C. SABISTON, JR., Durham, North Carolina

Although positive end-expiratory pressure (PEEP) is being employed in the management of respiratory insufficiency, many of its physiologic effects remain undetermined. The cardiopulmonary effects of 0, 5, 10, and 15 cm PEEP were studied in 10 tranquilized baboons ventilated at 15 ml/kg with room air. Hemodynamic measurements, analysis of arterial and expired gases were done, and pulmonary ventilation and blood flow ratios (V/Q) determined using 133Xe and a Baird-Atomic 70 Scanning Gamma Camera. V/Q ratios were computed in three lung zones: upper zone (Z I), middle (Z II), and lower (Z III). These measurements were repeated after injection of .06 - .08 mg/kg oleic acid into the right atrium.

In the normal lung, there was significant improvement in oxygenation at 5 cm PEEP (pO₂ 83.3 ±3.1 → 92.3 ±2.4)* secondary to improved ventilation of Z III (V/Q .81 → 1.00)*, but PEEP greater than 5 cm produced increasing mismatch of ventilation and perfusion. The V/Q data were: Z 1 5 PEEP - 1.42 → 15 PEEP -1.95*; Z II 5 PEEP 1.12 ->15 PEEP 1.22: Z III 5 PEEP 1.00 → 15 PEEP 1.24*.

After injection of oleic acid, shunting was evident at low levels of PEEP due to a shift of perfusion to Z I (V/Q .85)*. This mismatch of ventilation and perfusion was corrected in all three zones at 15 cm PEEP. V/Q data were: Z I 0 PEEP -.85 → 15 PEEP - 1.1*; Z II 0 PEEP - 1.22 → 15 PEEP 1.21; Z III 0 PEEP - 1.23 → 15 PEEP- 1.01.*

From these data, it is concluded that the use of PEEP in the injured lung has a beneficial effect by balancing regional ventilation and perfusion in addition to increasing functional residual capacity. Mechanisms of lung injury and pre-injury status of cardiopulmonary function remain critical in determining the effect of PEEP on hemodynamics as well as the pattern of regional ventilation and perfusion.

*(P<.05)

*By invitation

12. Prosthetic Reconstruction of the Trachea and Carina

WILLIAM E. NEVILLE and PAUL J. P. BOLANOWSKI*, Newark, New Jersey

While it is generally agreed that a primary anastomosis of the tracheobronchial tree is preferrable following resection, there are occasions when this is impossible because of the extent of the disease. Thus if airway continuity is to be restored, one is obligated to use an alternative method. Following extensive laboratory investigations, during the past 4½ years, twenty-six patients with trachea! stenosis due to benign stricture and malignancy have had airway reconstruction using a molded silicone rubber prosthesis. In 8 patients the distal trachea and carina were replaced with a bifurcated graft. One individual with multiple preoperative lung abscesses could never be weaned from the respirator and died in three weeks. Two other patients with malignancy who were completely relieved of their respiratory obstruction died 15 and 18 months following operation from disseminated cancer. The remainder are living from 1 to 4½ years.

Eighteen individuals have had the trachea reconstructed with a straight graft of silicone rubber. In 5 patients with long strictures the prosthesis was inyaginated into the upper and lower ends of the trachea and fixed into position with a few sutures. In 13 individuals a primary anastomosis of the cut ends of the trachea was performed. In this group there was one early death from erosion of the innominate artery and 5 late deaths from a variety of conditions, but unrelated to the prosthesis.

Although all the individuals have been able to effectively remove their secretions, in some of the patients there has been a propensity for granulomas to form at the distal suture line. This has been managed with intermittent bronchoscopy and fulguration. Despite the placement of a foreign body in an infected area, there have been no prosthetic disruption. From our observation this would seem to be a reasonable approach to the problem of extensive airway reconstruction.

*By invitation