Barry A. Levine

Chronic renal failure: Effect of hemodialysis on gastrointestinal hormones

Fifteen patients with chronic renal failure (serum creatinine level greater than 5 mg/dl) of long duration (more than 2 years) requiring hemodialysis were studied. Blood samples before and after 4 hours of hemodialysis were assayed for creatinine, blood urea nitrogen, potassium, calcium, glucose, insulin, gastrin, gastric inhibitory polypeptide, vasoactive intestinal polypeptide, pancreatic polypeptide, somatostatin, motilin, and neurotensin levels. Before dialysis, serum gastrin was minimally increased whereas gastric inhibitory polypeptide and pancreatic polypeptide were grossly increased compared with normal fasting values. Hemodialysis produced no changes in serum gastric inhibitory polypeptide, vasoactive intestinal polypeptide, pancreatic polypeptide, somatostatin, motilin, and neurotensin. Slight increases in serum insulin and gastrin levels may have occurred secondary to a dialysis-induced increase in the serum calcium level. The kidneys appear to be a major site of inactivation of insulin, gastrin, gastric inhibitory polypeptide, and pancreatic polypeptide. The gastrin level, although elevated in renal failure patients, may be suppressed by very high circulating levels of gastric inhibitory polypeptide.

Diagnosing appendicitis during pregnancy

Abstract In a 10 year period, 29 of 36 pregnant patients (81 percent) thought preoperatively to have appendicitis had the diagnosis confirmed at operation. Postoperative fetal complications included one intrauterine death and five premature births. There were no maternal deaths and morbidity was limited to atelectasis in five patients. Prompt surgical intervention in 90 percent of our patients did not prevent fetal complications.

The continuing challenge of popliteal vascular injuries

During a 6 year period, 35 patients with 56 popliteal vascular injuries were treated. Thirty-three arteries and 23 popliteal veins were affected. Fifty-four percent of the patients had both an arterial and a venous injury. Twenty injuries were due to penetrating trauma and 15 injuries to blunt force. An overall amputation rate of 16 percent followed attempts at vascular repair. Blunt injuries were associated with a 30 percent amputation rate, whereas penetrating injuries were associated with only a 5 percent amputation rate. When our results were reviewed and compared with those of others, several factors important for determining the rate of limb salvage in popliteal vascular injuries were noted: (1) early recognition and prompt treatment, (2) absence of blunt injury with attendant soft tissue damage; (3) resection of damaged arterial tissue with end-to-end anastomosis or saphenous vein grafting in conjunction with the liberal employment of local heparin and a Fogarty catheter thrombectomy, (4) repair of concomitant popliteal venous injuries; (5) use of completion arteriography to reveal technical errors amenable to correction at time of operation; and (6) fasciotomy, used liberally but selectively.

Site of splenic autotransplantation affects protection from sepsis

Using an animal model with bacteria delivered through the respiratory tract, the relative protective effects of subcutaneous and intraperitoneal splenic autotransplants were compared. Animals with intraperitoneal implants demonstrated a mortality not different from that in control animals and an early mortality significantly lower than found in splenectomized animals. Subcutaneous splenic autotransplantation provided no protective effect. The inability of extraperitoneal subcutaneous implants to protect against postsplenectomy pulmonary sepsis in our model suggests that subcutaneous splenic autotransplantation is an inappropriate alternative to intraperitoneal splenic autotransplantation in the clinical setting.

Glucagon enhances growth of cultured human colorectal cancer cells in vitro.

Early passage in vitro cultures of colorectal adenocarcinoma cells were used to determine if glucagon exerts a direct effect on growth of human colon cancer cells. Growth response assays indicated that glucagon generally stimulated growth between 2 and 10 micrograms/ml, with peak responses at 5 to 10 micrograms/ml. When glucagon-treated and control cultures were compared, 12 of the 14 cultures (86 percent) were stimulated by glucagon, with an increase in cells from 41 to 100 percent. The other two cultures did not respond to glucagon. These in vitro results suggest that glucagon may enhance growth of most colon cancer cells. Further studies on responsiveness to glucagon may help elucidate mechanisms of oncogenesis and suggest new therapeutic protocols for patients with colorectal cancer.

Simultaneous infusion of nitroglycerin and nitroprusside to offset adverse effects of vasopressin during portosystemic shunting.

In the present study, 52 patients with cirrhosis, portal hypertension, and variceal hemorrhage underwent either an elective or an emergency side-to-side portacaval shunt operation. Vasopressin was infused intravenously at 60 units/hour from just prior to abdominal incision until completion of the anastomosis. Eight of 35 patients who received vasopressin alone (23 percent) tolerated increased doses of 75 to 90 units/hour to obtain hemostasis. Four of 52 patients required simultaneous infusion of sodium nitroprusside to correct systemic hypertension. An additional 15 percent reduction in portal venous pressure occurred in these patients. Eleven of 13 patients with vasopressin-induced myocardial ischemia responded to simultaneous infusion of nitroglycerin. Further prospective studies are indicated to adequately delineate the dose and duration of therapy with either nitroprusside or nitroglycerin for simultaneous administration with intravenous vasopressin.

Direct portacaval anastomoses are safe and effective in patients with previous abdominal operations

Direct side-to-side portacaval anastomosis is employed exclusively in our institution to control variceal hemorrhage regardless of previous operative history. A consecutive, unselected group of 152 such patients was reviewed to ascertain the effect of previous major abdominal operation on operative difficulty and outcome. Fifty patients, with previous operations ranging from biliary and gastric procedures to thrombosed distal splenorenal shunts, were compared with 102 previously unoperated patients. This comparison led to the conclusions that side-to-side direct portacaval anastomosis may be carried out in patients with a previous major abdominal operation without an increased risk in mortality or morbidity, and that although intraoperative blood loss and transfusion requirements were increased in previously operated patients, these factors (along with operative time) could be minimized by use of intraoperative vasopressin and electrocautery. Thus, alternative shunting procedures, with their increased thrombosis and rebleeding rates, need not be considered in such patients.

The impact of emergency medicine on surgical care in the emergency ward.

Abstract The Committee on Issues of the Association for Academic Surgery surveyed the Associations membership, surgical department chairmen, and university hospital emergency department directors as to their attitudes about the role of surgeons and emergency medicine specialists in emergency care. Major differences in attitudes exist between surgeons and nonsurgeons regarding the surgeons role in the emergency department. Although surgeons want to preserve a dominant role in emergency care, they have little interest in being in charge of emergency wards on a day to day basis. Emergency medicine specialists have a tendency to function independently, even to the point of independently performing emergency surgical procedures. In emergency departments led by nonsurgeons there is decreased participation of surgical house staff in the resuscitation of the critically injured patients. This may result in inadequate training of surgical residents in acute trauma care and ultimately result in lowered overall standards of care in critically ill patients. An important question is whether surgeons can continue to abdicate their present reponsibilities in the emergency ward and yet maintain their essential role in the preoperative care of the emergency patient.

Responsibility of Clinical Surgeons Who Write-Reply

In Reply .—I would like to thank Dr Adar for his interest in our study. However, I would respectfully take issue with his contention that our conclusions are unsupported by our data. The quote used by Dr Adar from our abstract contains the word potential in relation to curability of lesions. This refers to a distinction between patients with stage III and IV disease, the latter of whom are not even potentially curable. However, even in the presence of positive regional nodes (stage III), a small but significant cure rate has been associated with resection. Certainly, no patient with stage III disease has been cured without resection. Thus, the misdiagnosis by CT scan as stage IV, when the correct stage is III, could potentially be to their disadvantage. While Dr Adar insists on lumping all patients with stage III and IV disease together, our only claim for overdiagnosis by CT