Experiences with an artificial sphincter to establish anal continence in dogs.

An implantable device for establishing urinary continence has been developed and has received FDA approval (AS 800, American Medical Systems, Inc.). The authors have applied this device to the control of anal continence in dogs. Fifteen mongrel dogs underwent either anal sphincter disruption (7) or abdominal-perineal resection (8). Such animals have bowel movements almost hourly. In each case, the device was implanted at the time of surgery. In dogs with working cuffs and disabled or absent sphincters, continence was maintained in seven out of 15 animals for periods of 4-8 hours. After cuff activation, intraluminal cuff pressures of 50-70 cm of water achieved continence for a period of 8 hours. In animals sacrificed from 1 to 12 months after implantation, the device was found to be well tolerated by the body with minimal fibrosis of the mucosa or muscularis of the bowel. Complications observed in the same four out of 15 animals during the study period were infection, device extrusion, and device malfunction. Infection resolved with local wound care and antibiotics (3/4) and the device was successfully replaced in two out of four instances of extrusion. With cuffs of proper size and pressure, this appliance may be effective in the control of human anal incontinence via the establishment of continent perineal colostomies following an abdominal-perineal resection.

Rapid control of hemorrhage of the scalp in the patient with trauma.

The use of Leroy-Rainey clips is rapid and effective in controlling extensively bleeding wounds of the scalp. They are a valuable aid in assessment and stabilization of patients with trauma.

Tube thoracostomy and trauma--antibiotics or not?

Controversy persists regarding the use of antibiotics in association with t tube thoracostomy for trauma patients. We conducted a prospective randomized study of patients requiring tube thoracostomy for pneumo- and/or hemothorax complicating blunt or penetrating thoracic trauma in an attempt to assess the efficacy of prophylactic antibiotic therapy. Fifty-eight patients were included in the study. The control group (Group I) included 28 patients who received no antibiotic therapy: the experimental group (Group II) included 30 patients who received cefoxitin (1.0 gm IV q 6 h) commencing before tube thoracostomy and terminating 12 hours after its removal. The incidence of infectious complications (pneumonia and/or empyema) was recorded. Among the patients not receiving antibiotics, eight of 28 (29%) developed infectious chest complications. Of the patients receiving antibiotics, there was one infectious complication (3%). This difference is statistically significant (p = 0.0227). Cultures demonstrated significant conversion from negative to positive both within each group and between groups. The organism most commonly recovered was S. aureus. Our findings strongly suggest that patients requiring tube thoracostomy for trauma, whether blunt or penetrating, should receive the benefit of systemic prophylactic antibiotic therapy.

A nonheparinized muscle model for studies of ischemia-reperfusion injury.

An understanding of the basic metabolic, functional, and histologic features of skeletal muscle injury secondary to ischemia and reperfusion has thus far been hampered by the lack of an adequate animal model. We have developed an in vivo isolated skeletal muscle preparation amenable to ischemia-reperfusion studies and the investigation of therapeutic modalities. The model is autoperfused and, most importantly, nonheparinized. The use of a nonheparinized model is essential following the work of Hardaway, recently confirmed by Fry, showing that alterations of flow in the shock state occur when heparin is used, invalidating other models as true replicas of clinical situations. The gracilis muscle in the canine hindlimb and its contralateral control are isolated on their neurovascular pedicles after detachment of fascial boundaries and meticulous ligation of all collateral vascular supply. Prolonged arterial occlusion can be accomplished by clamping proximal and distal to the point of origin of the gracilis artery from the superficial femoral artery. In a similar fashion, occlusion above and below the gracilis vein is effected intermittently to collect venous efluent during reperfusion. Preliminary studies of 100 muscle preparations subjected to 3 or 15 hr of ischemia, followed by 2 hr of reperfusion, demonstrate depression of oxygen utilization of 5% of control values during early reperfusion with improvement to 30% of control values over 2 hr. Contractility, abolished during ischemia, returns to 20% of control values after 2 hr of reperfusion.

Surgical management of bleeding esophageal varices. Results with 80 cases.

This report presents results of surgery for bleeding esophageal varices in 80 patients. A prospective randomized study addresses the efficacy of the distal splenorenal shunt (DS) versus the mesocaval shunt (MS) in 50 patients undergoing elective surgery. An additional 30 patients underwent emergency MS for uncontrollable hemorrhage. In the elective series, patients averaged "B" according to Child's Classification. Operative mortality rates were similar (5%). Incidences of encephalopathy were also similar (10%). Those patients undergoing MS experienced an overall operative mortality of 9 per cent, which included emergency shunts (operative mortality 13%). This latter figure is the lowest in the world's literature. Our technique of mesocaval shunting emphasizes short (mean, 3.8-cm) and wide (mean, 21.5-mm) cloth prostheses. Utilizing this approach, we have been able to reduce operative portal venous pressure from a mean (x +/- SE) of 40.1 +/- 1.9 to 13.1 +/- 0.6 cm H2O. The latter value correlated inferior vena caval pressure, 11.8 +/- 0.6 and central venous pressure (recorded by the anesthesiologist) 11.4 +/- 0.5 cm H2O. This is the highest reduction (67%) in portal pressure thus far recorded and reflects our emphasis upon meticulous and extensive dissection of the involved structures. The former minimizes blood loss, which in our hands has been minimal (0.45 +/- 0.18 units per case), reducing the threat of further liver damage; the latter facilitates the "optimal shunt," one which returns portal venous pressure to normal.

The Eck-Pavlov connection.

In 1877, N. V. Eck described the surgical creation of a fistula between the inferior vena cava and the portal vein in a dog. At the same time he suggested that this operation might be of use in humans for the treatment of ascites. But it was not until more than 50 years later that A. O. Whipple's report of his experience with Eck's operation ushered in the so-called modern era of the portacaval shunt. While there has been sporadic reports about various phases of Eck's life, most reference books do not even give the date of his death, and some references disagree as to the date of his birth. He has been mistakenly placed among the physiologists rather than the surgeons of Russia, and while quoted as a "brilliant student," he has been accused of being "ill-suited" to his profession by the same source. For his intense interest in other areas such as mining and geology, he is depicted as an erratic man who sought something he probably never found. It is said that for 13 years he was divorced from medicine and surgery, when in fact it was during this period that he performed the only clinical portocaval shunt of his career (and it was successful). Unable to find answers to many questions concerning the 59 years of this man's life in the Western world, a recent trip to Leningrad by the author was informative, interesting, and even surprising. Eck's rarely quoted connection with I. P. Pavlov was more than just an acquaintance, and the famed "Eck-fistula" of the Western world is known as the "Eck-Pavlov shunt" in Leningrad.

Effects of vasopressin on cardiac output and its distribution in the subhuman primate.

The effects of vasopressin, when administered as intravenous bolus injections and infusions, on cardiac output and the distribution of blood flow to the splanchnic vascular beds were studied in six anesthetized rhesus monkeys. Vasopressin as bolus injections caused dose-dependent decreases in superior mesenteric arterial blood flow. However, small reductions in cardiac output were observed only at the highest doses concomitant with increases in systemic arterial pressure. When vasopressin was infused at the highest dose (5 X 10(-2) units kg-1 min-1) for 10 minutes, cardiac output was unaffected; but sustained reductions in superior mesenteric arterial blood flow and increases in arterial pressure and total peripheral resistance were observed. Infusions of vasopressin (5 X 10(-3) units kg-1 min-1) caused significant and sustained reductions in superior mesenteric arterial blood flow and increases in arterial pressure but no measurable effects on cardiac output or total peripheral resistance. However, there was a significant redistribution of blood flow away from the stomach, small and large intestines, spleen, and pancreas toward the liver (hepatic artery), with no statistically significant change in renal blood flow. On the assumption that comparable responses exist among primates, these data support the clinical use of vasopressin to control gastrointestinal hemorrhage and to offer a probably ideal dose and route of administration.

Hemodynamics of an anastomotic arteriovenous fistula.

Various vascular surgical techniques have been employed to increase both graft patency and limb survival when the prognosis for limb salvage in arteriosclerotic patients is especially poor due to a diseased outflow tract. Ibrahim et al described the creation of an anastomotic arteriovenous fistula in distal tibial bypasses as the reconstructive procedure of choice in severely ischemic extremities unsalvageable by more conventional methods. This study presents the hemodynamics of an anastomotic arteriovenous fistula under such circumstances. Four adult mongrel dogs were anesthesized, and a femoral artery and vein were exposed from the groin to the knee. The femoral artery was ligated in midthigh, and the ligated segment was than bypassed using an umbilical vein graft. The distal anastomosis included an arteriovenous fistula. Flow was measured electromagnetically, and pressure was measured with intravascular catheters attached to strain gauges. The creation of an anastomotic arteriovenous fistula rapidly leads to a reversal of flow in the distal artery, distal arterial hypotension, and distal venous hypertension. Its clinical use in contraindicated as a result of our experimental observations.

Changing attitudes toward management of cancer of the colon and rectum.

Changes in the attitudes of surgeons toward the management of cancer of the colon and rectum over a 5-year period were assessed by analysis of responses of general surgeons to a 21-item questionnaire on colon cancer from 1978 and 1983. Comparisons of the responses revealed that the use of routine preoperative liver scans has decreased from 57 to 45 per cent. Transanal resection of villous adenoma of the rectum is used more often (44% in 1983 versus 34% in 1978). For obstructing carcinoma of the colon, a two-stage procedure is used more often, with 46 per cent of the respondents in favor of this approach in 1983 compared with 29 per cent in 1978. The use of staplers for colon anastomoses following resection has also increased with 44 per cent surgeons in 1983 using this technique always or frequently compared with 21 per cent in 1978. Following anterior resection, 66 per cent of respondents in 1983 seldom or never use a transverse colostomy (54% in 1978). The number of surgeons closing the perineal wound over suction drains following an abdominoperineal resection has increased from 46 per cent (1978) to 63 per cent in 1983. Sphincter-saving procedures for carcinoma of the rectum are used by a large number of surgeons in 1983 (29% versus 9% in 1978). An increase is noted in the use of preoperative radiation therapy for selected cases of rectal cancer (53% in 1978 to 68% in 1983).(ABSTRACT TRUNCATED AT 250 WORDS)

Interval breast cancer: a more aggressive subset of breast neoplasias.

It has been suggested that interval breast cancer (breast cancer found within 12 months of a negative screening examination) exhibits a more virulent behavior than those found by the screening clinic. To test this hypothesis, 120 new cases of breast cancer were retrospectively reviewed from our Breast Screening Center. These patients were divided into three groups--interval cancer cases, lesions found at initial screening, and lesions found at subsequent screening. Statistically significant differences seen in our interval cancer cases included a higher percentage of positive axillary nodes, higher overall mortality rate, and lower 6-year survival rate as calculated by left table analysis. The remaining data, although not statistically significant, demonstrate a parallel trend toward a more malignant behavior. It is concluded that interval breast cancers are more aggressive forms of breast neoplasias.

The U.S. M-16 rifle versus the Russian AK-47 rifle. A comparison of terminal ballistics.

The standard U.S. military rifle (M-16) is substantially more destructive than its Russian counterpart (AK-47) when fired at short range into clay blocks, despite the fact that the AK-47 is of larger caliber and fires a much heavier bullet with a kinetic energy (muzzle) 25% greater when compared to the M-16. The decisive factor is the 40% greater muzzle velocity of the M-16.

Current attitudes in the management of thyroid cancer.

The opportunity to assess the current attitudes of surgeons in the management of thyroid cancer was afforded by the responses to a questionnaire that was part of a "Questionnaire Course." The majority of the 72 respondents have a conservative surgical approach to thyroid cancer, find frozen section useful, recommend total thyroidectomy for medullary cancer, seldom or never split the sternum in performing thyroidectomy, and recommend visualization of the recurrent laryngeal nerves and the parathyroids. Opinions however, are divided on several other issues. Forty-two per cent (versus 34%) request ultrasound before removal of a "cold nodule." For follicular carcinoma, 44 per cent perform lobectomy with isthmustectomy, 29 per cent perform total ipsilateral lobectomy and subtotal contralateral lobectomy, and 23 per cent perform total thyroidectomy. Following lobectomy for follicular carcinoma, recommended treatments are radioactive iodine (25%), thyroid suppression (21%), and total thyroidectomy (48%). For anaplastic cancer, 44 per cent perform total thyroidectomy and 40 per cent perform radiation therapy. Histologically positive nodes are managed by modified radical neck dissection (61%) or by "berry picking" (23%). It is concluded that despite agreement on several therapeutic approaches for thyroid cancer, certain controversial issues remain unresolved.

The postal tubal ligation syndrome.

PIP: The frequency of symptoms following tubal ligation calls for an examination of the basic problem with the methods now used. This discussion recommends a modification of tubal ligation which as performed during the past 2-1/2 years has been symptom free, post operatively. What is meant by symptom free is those symptoms which can be directly related to tubal ligation. Symptomatology is complex and insidious. Characteristically, there is a latent period of no symptoms. This asymptomatic period may be totally subjective and may last several years during which time the correlation between surgery and symptoms is obscured. This is particularly the case if purely symptomatic therapeusis has had some degree of success. The latest period is followed by the gradual development of the following: menstrual disorders; abdominal pain which is usually located in the lower abdomen and is of 2 varieties, i.e., dysmenorrhea and nonmenstrual pain; and infection. Physical examination demonstrates little. This set of symptoms, which has been documented also by Poma et al., and when taken as a whole, constitutes a syndrome which should be termed the posttubal ligation syndrome. These patients give a history of repeat X-rays, biopsies, endoscopies, and surgical exploration. Some of these patients have had 4 or 5 celiotomies. A modification of the traditional method of tubal ligation definitely requires consideration. The characteristics of the oviducts which need mention and emphasis are reviewed. On the basis of the reviewed considerations, it becomes obvious that smooth transport of the ovum is a necessity and that obstruction in the tubes will cause a reaction similar to obstruction anywhere in the body. Tubal ligation should be performed in such a manner so as not to obstruct the ova from passing down the tube. The tubes should be cut fairly close to the uterus and be tied. The rest of the tube from fimbria to the isthmus should be left open. In this manner, the ovum passes into the fimbriated end of the tube and is gently passed out back into the peritoneal cavity. A sort of blind loop is created. Although this technique has been performed in only 6 cases, results have been good.^ieng