Treatment of primary peritoneal mesothelioma by hyperthemic intraperitoneal chemotherapy.

Perfusion of the peritoneal cavity with chemotherapy agents under hyperthermic conditions has been utilized by several investigators in the treatment of intra-abdominal malignancies. Based on the concept that hyperthermia may potentiate the cytotoxic effects of chemotherapeutic agents, we embarked on a clinical trial of two-stage peritoneal chemotherapy for patients with primary peritoneal mesothelioma, a neoplasm unresponsive to traditional systemic chemotherapeutic regimens. In stage I, patients underwent surgical debulking of gross disease and placement of an intraperitoneal infusion catheter, through which intraperitoneal chemotherapy was administered for four months. Stage II consisted of debulking of residual tumor, placement of two transabdominal perfusion cannulae and administration of high-dose intraperitoneal chemotherapy at 40 degrees C using a simple, disposable perfusion circuit. Flow rates were maintained at 1 l/min, and inflow and outflow temperatures maintained at 42 and 40 degrees C, respectively. To date, three patients have undergone both phases of the protocol, with no perioperative complications related to either hyperthermia or end-organ toxicity. One patient died of progressive disease after three months, and two patients are alive and well. One patient developed a small bowel anastomotic leak three weeks after operation. In summary, intraoperative hyperthermic peritoneal chemotherapy may play a role in novel approaches to the treatment of peritoneal malignancies previously unresponsive to traditional chemotherapeutic regimens.

Inhaled nitric oxide improves hemodynamics in patients with acute pulmonary hypertension after high-risk cardiac surgery.

Severe pulmonary hypertension and right-sided circulatory failure (RSCF) represent an increasing cause of morbidity and mortality in patients undergoing high-risk cardiac surgery. Increased pulmonary vascular resistance in the setting of cardiopulmonary bypass (CPB) may further lead to decrease blood flow across the pulmonary vascular bed; thereby decreasing left ventricular filling and cardiac output. Current management techniques for RSCF include both nonspecific vasodilator and inotropic agents (often limited by systemic hypotension) and the placement of right ventricular assist devices (associated with increased perioperative morbidity). Inhaled nitric oxide (NOi) represents a novel, specific pulmonary vasodilator that has been proven efficacious in these clinical settings. We evaluated 34 patients in 38 operations who underwent cardiac surgery at Columbia Presbyterian Medical Center, and who received NOi (20 ppm) through a modified ventilatory circuit for hemodynamically significant elevations in pulmonary vascular resistance. Nine patients underwent cardiac transplantation, three patients bilateral lung transplantation, 16 patients left ventricular assist device placement and 10 patients routine cardiac surgery. Patients receiving NOi exhibited substantial reductions in mean pulmonary artery pressure (mPAP) (34.6 +/- 2.0 to 26.0 +/- 1.7 mmHg, p < 0.0001), with improvements in systemic hemodynamics, mean arterial pressure (68 +/- 3.1 to 75.9 +/- 2.0 mmHg, p = 0.006). In five cases, patients could not be weaned from CPB until NOi was administered. Patients were maintained on NOi from 6 to 240 h postoperatively (median duration 36 h). Inhaled NO induces substantial reductions in mPAP and increases in both cardiac index and systemic blood pressure in patients displaying elevated pulmonary hemodynamics after high-risk cardiac surgery. NO is, therefore, a useful adjunct in these patients in whom acute pulmonary hypertension threatens right ventricular function and hemodynamic stability.

Clinical evaluation of setting pump occlusion by the dynamic method: effect on flow.

Pump manufacturers recommend setting roller pump occlusion such that the level of a 100 cm column of crystalloid drops 2.5 cm/min (Sarns, 8000 Modular Perfusion System, operator's manual, roller pump software version 2.3L. May 1993; 2.1-2.14). Though this almost occlusive setting ensures accurate pump flow, it has been shown to cause more hemolysis than nonocclusive pumps (Noon GP, Kane LE, Feldman L et al. Reduction of blood trauma in roller pumps for long-term perfusion. World J Surg 1985; 9: 65-71). We conducted a clinical study (n = 19) to compare the standard occlusion method with the dynamic method and to determine the accuracy of flow for the nonocclusive pump. Standard occlusion was set by clamping the pump tubing distal to the arterial line filter and timing the drop in pump outlet pressure as indicated by a pressure transducer connected to the filter. The occlusion setting, expressed in mmHg/s, was recorded for each roller at two specific points along the raceway. The pump was then set nonocclusively with the dynamic method using the Better Header (BH) (Circulatory Technology, Oyster Bay, NY, USA). Readings of the change in pressure in the same two selected points on the raceway were taken. The latter was repeated after discontinuation of bypass. Flow was recorded throughout the procedure from both roller pump output display and a flow meter (Model #109 Transonic, Ithaca, NY, USA). The average drop in pump outlet pressure for the standard method was 1.3 +/- 4.0 (range 0-18 mmHg/s), and for the dynamic method was 38 +/- 28 (range 1.2-89 mmHg/s). Off bypass, the average reading was 44 +/- 38 (range 2.0-103 mmHg/s). Regression analysis indicates that patient flow, when corrected for retrograde flow by the dynamic method, equals 1.003 x revolutions per minute + 40 ml/min (r2 = 0.964). The average error between indicated pump flow, corrected for retrograde flow, was -1% (range from -6.7 to 6.6%). We conclude that the BH allows nonocclusive setting (30 times less than our standard method) without sacrificing pump flow accuracy.