Cardiovascular effects of protamine sulfate are dependent on the presence and type of circulating heparin.

Man's response to clinical doses of protamine is highly variable. We investigated the influence of circulating heparin in nine swine (mean age 6 weeks, weight 10 kg). Through a sternotomy we implanted an electromagnetic flow probe around the pulmonary artery for cardiac output determination and catheters into the ascending aorta, pulmonary artery, right atrium, and left atrium for pressure monitoring. Each animal was allowed to recover and was studied awake on 3 consecutive days. Protamine, 3 mg/kg, beef lung heparin, 300 U/kg, and pork mucosal heparin, 300 U/kg, followed by protamine, were given in rotation by intravenous bolus. Protamine alone had no effect. Beef lung heparin followed by protamine induced a marked increase in pulmonary artery pressure (mean 38 +/- 3 to 51 +/- 5 mm Hg in 3 minutes). Pulmonary vascular resistance doubled (mean 0.12 +/- 0.01 to 0.23 +/- 0.04 R within 4 minutes), returning to normal within 15 minutes. Cardiac index and aortic pressure changed minimally. Pork mucosal heparin followed by protamine induced a similar but greater increase in mean pulmonary arterial pressure; however, cardiac index fell significantly (p less than 0.05, 207 +/- 16 to 117 +/- 16 ml/kg/min-1 at 1 minute) despite a regular rhythm and adequate left atrial filling pressure. Thus cardiac contractility was depressed. Systemic hypotension occurred in three of nine pigs. Both mean pulmonary vascular resistance and systemic vascular resistance increased (0.12 +/- 0.01 to 0.67 +/- 0.25 R and 0.40 +/- 0.04 to 1.09 +/- 0.25 R, respectively), significantly (p less than 0.05) more with pork than beef heparin. These data demonstrate that cardiovascular response to protamine neutralization varies significantly in regard to the type of heparin used. Furthermore, circulating heparin is required to produce those effects previously attributed to protamine alone.

Nuclear cardiac ejection fraction and cardiac index in abdominal aortic surgery.

Since atherosclerotic heart disease results in more than half of the perioperative deaths that follow abdominal aortic surgery, a prospective protocol was designed for preoperative evaluation and intraoperative hemodynamic monitoring. Twenty men who were prepared to undergo elective operation for aortoiliac occlusive disease (12 patients) and abdominal aortic aneurysm (eight patients) were evaluated with a cardiac scan and right heart catheterization. The night prior to operation, each patient received volume loading with crystalloid based upon ventricular performance curves. At the time of the operation, all patients were anesthetized with narcotics and nitrous oxide, and hemodynamic parameters were recorded throughout the operation. Aortic crossclamping resulted in a marked depression in CI in all patients. CI remained depressed P less than 0.05 after unclamping in the majority of patients. There were two perioperative deaths, both from myocardial infarction or failure. Both patients had ejection fractions less than 30% and initial CIs less than 2 L/M2, while the survivors' mean ejection fraction was 63% +/- 1 and their mean CI was 3.2 L/M2 +/- 0.6. We conclude that preoperative evaluation of ejection fraction can select those patients at a high risk of cardiac death from abdominal aortic operation. These patients should receive intensive preoperative monitoring with enhancement of ventricular performance.

A randomized study of beef lung and pork mucosal heparin in cardiac surgery.

Beef lung heparin had substantially greater anticoagulant activity than pork mucosal heparin during a preoperative heparin tolerance test and also during cardiopulmonary bypass (CPB) in 100 randomized patients. Supplemental heparin was needed during CPB in many more of the patients receiving pork mucosal heparin. Heparin rebound was detected in 16 patients; this low incidence may result from a relatively high protamine:heparin ratio. There was notably less postoperative bleeding in those who received beef lung heparin. Platelet counts were not altered by either type of heparin. It is surprising that the preoperative tolerance curve only predicted heparin sensitivity during CPB in one-half of the patients. Blood activated coagulation time levels were increased markedly by hemodilution and further raised by hypothermia. These data demonstrate that beef lung heparin is better than pork mucosal heparin for CPB.

Age and morbidity of vagotomy with antrectomy or pyloroplasty.

Seven hundred ninety-three vagotomies with either pyloroplasty (645 patients) or antrectomy (148 patients) were reviewed between 1970 and 1981. Mortality was lowest with elective pyloroplasty (0.4 percent) followed by elective antrectomy (0.7 percent), and emergency pyloroplasty (5.1 percent). The risk of death was significantly higher (p less than 0.05) for the older half of the population (older than 55 years of age). Major morbidity was lowest after elective pyloroplasty (6.3 percent) when compared with elective antrectomy (10.6 percent), and greatest after emergency pyloroplasty (18.1 percent). Proved ulcer recurrence was most frequently seen after pyloroplasty (4.5 percent) and least frequently seen after antrectomy of age) had a significantly decreased risk of ulcer recurrence (p less than 0.001). Disabling sequelae occurred in 3.6 percent of those who underwent pyloroplasty, in 5.6 percent of those who underwent antrectomy with Billroth I reconstruction, and in 8.5 percent of those who underwent antrectomy with Billroth II reconstruction. Significantly more patients who underwent antrectomy with Billroth II reconstruction required reoperation (p less than 0.01) than did those who underwent either pyloroplasty or antrectomy with Billroth I reconstruction. Although antrectomy has become a popular operation, vagotomy combined with pyloroplasty is still the procedure of choice in patients over the age of 55 years. In those requiring emergency operations for duodenal ulcer, and in those in whom antrectomy is technically difficult because of a badly scarred duodenum. Billroth II reconstruction should be avoided after vagotomy and antrectomy.

Changes in arterial oxygenation and pulmonary shunt during thoracotomy with endobronchial anesthesia.

Eight-five veterans underwent thoracic operations, mainly for carcinoma of the lung, with the aid of endobronchial anesthesia. Changes in arterial oxygenation (PaO2) and pulmonary shunt (Qs/Qt) were determined sequentially. Mean PaO2 after both lungs were ventilated for 20 minutes, supine, with 100% oxygen was 433 +/- 8 mm Hg. Selective ventilation of one bronchus dropped this value significantly (p less than 0.01) to 247 +/- 13 mm Hg. PaO2 did not change appreciably when the patient was turned to the lateral position; however, following pleurotomy there was a significant (p less than 0.01) decline in mean PaO2 to a nadir of 178 +/- 17 mm Hg at 90 minutes. Transient hypoxemia (PaO2 less than 60 mm Hg) occurred in 11 of 85 patients, most frequently (7/11) during positioning. Preoperative PaO2 PaCO2, forced expiratory volume in 1 second, forced vital capacity, or medical status did not predict hypoxemia. Qs/Qt increased significantly (p less than 0.01) at the onset of atelectasis from 18% +/- 0.9% to 25.4% +/- 0.9% but did not change with turning. The maximal mean Qs/Qt (30.3% +/- 1.1%) occurred immediately after opening the pleura and then decreased significantly (p less than 0.05), despite the fall in PaO2. Blood loss greater than 1,000 cc (n = 10), especially with hypotension, resulted in a significant increase (p less than 0.05) in Qs/Qt and a fall in PaO2. Thus pulmonary vascular adaptation to acute atelectasis has been demonstrated in man, and this, as in animal models, fails with hemorrhage.

Pharyngoesophageal pulsion diverticulum (Zenker) in a ten-year-old boy.

Posterior pharyngoesophageal pulsion diverticula are rare during the pediatric years. We present the third case (a 10-yr-old). Proper diagnosis was made during fiberoptic esophagoscopy.

Pulmonary circulatory adaptation to acute atelectasis in man.

Pulmonary functional veno-arterial shunt determinations were made breathing 100% oxygen in thirty consecutive patients during thoracotomy with one-lung anesthesia. Initially, with both lungs ventilated (FiO2 100%), the mean shunt value was 18.1 +/- 1.2% (S.D.). With the collapse of one lung by deflation and surgical pneumothorax, the shunt rose to 36.0 +/- 1.5%. With time the value fell: 36.0 +/- 1.5% at five minutes, 30.3 +/- 1.4% at fifteen minutes, 30.3 +/- 1.4% at thirty minutes, 28.1 +/- 1.4% at sixty minutes, and 24.6 +/- 2.8% after two hours. This trend was significant at a p value of less than 0.001. This study for the first time documents in man the phenomenon of pulmonary circulatory adaptation to acute atelectasis.

Parathormone and perinatal calcium homeostasis.

Plasma parathormone (PTH) and calcium concentrations were measured in 309 specimens collected from 190 newborns during the first 7 days of life. The patient material consisted of 51 preterm, 130 term, and 9 postterm infants, including 22 infants of diabetic mothers (IDM), 38 infants with hypocalcemia, and 25 asphyxiated infants. PTH was detectable, although in low concentrations, in cord blood samples despite the presence of elevated calcium concentrations. Postpartum, PTH concentrations in term, appropriate for gestational age (AGA) infants remained low during the first 2 days of life; a significant (P less than 0.05) and sustained increase in plasma hormone levels was noted starting on day 3. PTH concentrations in IDM and preterm infants remained low for 3 days and a significant hormone increase did not occur until day 4. Hypocalcemia was common in IDM and asphyxiated infants; these infants accounted for two-thirds of all hypocalcemic infants. The profile of plasma calcium in IDM during the first week of life was different than that of any other group of infants. Plasma calcium concentrations remained depressed over this period of time and exhibited a temporary drop on day 4 accompanied by an increase in plasma PTH levels. Asphyxiated infants exhibited low plasma calcium concentrations, despite PTH levels that were significantly (P less than 0.007) higher than those of age-matched term AGA newborns.