Calcium dobesilate: pharmacological profile related to its use in diabetic retinopathy

Calcium dobesilate (Doxium) is used in the treatment of diabetic retinopathy. Clinical studies show a slowdown of the progression of the disease after long-term oral treatment. The main action of the drug is related to a reduction of microvascular permeability as measured by different parameters and methods (vitreous fluorophotometry, retinal haemorrhages, skin capillary resistance, blood albumin leakage, blood viscosity) leading to improved visual acuity. The pharmacological activity may be explained in part by the antioxidant properties of calcium dobesilate and its action on endothelium through the synthesis of nitric oxide, increasing the endothelium-dependent relaxation. The antioxidant effect was demonstrated in different in vitro and in vivo models by decreasing the peritoneal permeability in rats induced by pro-oxidant substances. Moreover, vascular leakage was also decreased by calcium dobesilate in a reperfusion model in streptozotocin induced diabetic rats after ischaemia of the central artery of the retina. Doxium may also preserve vascular endothelial function by acting directly as antioxidant to protect lipids from peroxidation.

[Surgical therapy of mesenteric infarct]

Acute mesenteric infarction represents less than 1-2% of all surgical emergencies but is responsible for many lethal events. A successful management requires very efficient diagnostic and therapeutic measures. Cases with established bowel infarction are associated with a mortality rate of 80-90% since years. In the last 10 years some hospitals offering an aggressive pre-, per- and postoperative multimodal therapy could reduce the mortality in selected series to 50-60%. One of the most important factors to reduce the mortality is beneath early diagnosis the emergency angiography and the angiography-associated treatment like intraarterial application of vasodilators, even in occlusive forms of mesenteric infarction. But this concept is seldom applicable to small hospitals because of the partially lacking availability of angiography. We present a concept of treatment taking into account this fact. Generous indication for emergency laparotomy in patients suspect of acute mesenteric ischemia is the central pillar of our concept. We also plea for a very restraint indication in biologically old multimorbid patients presenting a sum of negative prognostic factors and consider in these cases the reluctant attitude as an ethically and medically positive behaviour.

Hyperventilation enhances transcapillary diffusion of sodium fluorescein

Voluntary hyperventilation (HV) provokes hemoconcentration due to a loss of fluid from the intravascular space. In 10 healthy male volunteers the hypothesis was tested whether HV increases transcapillary fluid shift into the interstitial compartment. For this purpose, fluorescent light intensity (FLI) alterations after intravenous injection of sodium fluorescein (Na fluorescein) before and during 3 min of HV were determined. Concomitantly, temperature and microvascular skin flux (laser Doppler fluxmetry, LDF) were recorded continuously. Hematocrit and serum proteins, as markers of hemoconcentration, increased significantly from 41.2 +/- 2.3 to 42.7 +/- 2.0% (p = 0.0023) and from 69.5 +/- 3.4 to 72.9 +/- 3.0 g/l (p = 0.0005, respectively). Skin temperature and LDF showed no changes during HV compared to baseline levels. Interstitial FLI indicating transcapillary diffusion of Na fluorescein was significantly higher (p < 0.001) during HV compared to the values recorded during the baseline period. The exact mechanism of enhanced transcapillary diffusion of Na fluorescein is not known. The distinct increase in FLI without a significant change in microvascular skin flux suggests an HV-induced increase in capillary pressure or an enhancement in capillary permeability for water and small solutes.

Temporary exclusion of the perforated esophagus using a linear vascular stapler: a new surgical treatment

BACKGROUND/AIMS

A new technique using a linear staple suture for temporary exclusion of the perforated esophagus is presented.

MATERIALS AND METHODS

The procedure is combined with diversion of esophageal fluid by nasogastric tube and drainage of the periesophageal compartments by silicon drains. A gastrostomy is used to drain the stomach for 48 hours, and later for enteral nutrition. Since the suture line reopens spontaneously after approximately 10 days there is no need of reoperation.

RESULTS

This method allows diversion of esophageal fluids and therefore enhances effective healing of esophageal perforations after primary repair. Complete spontaneous recanalization of the esophagus occurs approximately two weeks after operation.

CONCLUSIONS

The combination of primary repair of an esophageal perforation with esophageal exclusion by using a linear stapler and diversion of esophageal fluid contents by naso-esophageal tube and gastrostomy is a simple effective procedure. Further experience and studies may be needed to verify the usefulness and place of this technique in armamentarium of the visceral surgeon.

Isolated late metastasis of a renal cell cancer treated by radical distal pancreatectomy

A 53-year-old man underwent right nephrectomy for a locally renal cell carcinoma with concomitant resection of a solitary metastasis in the right lung. Ten years later, he presented with haematochezia caused by a tumour in the tail of pancreas, invading the transverse colon and the greater curvature of the stomach. The tumour was radically resected, and histological examination revealed a solitary metastasis of the previous renal cell carcinoma. This case illustrates a rare indication for pancreatic resection because of pancreatic metastasis.

Is there still a place for abdominoperineal resection of the rectum?

During the past two decades, low anterior resection (LAR) with colo-rectal or colo-anal anastomosis has replaced abdominoperineal resection (APR) as the primary surgical therapy for rectal cancer. Several studies, although not prospectively randomized, have shown that the outcome after LAR with deep anastomosis and APR is comparable concerning mortality, local recurrence rate and survival. Adequate clearance of the tumour, and not the surgical procedure performed, is the determinant factor influencing the outcome. Whereas most tumours in the upper third and mid-rectum are amenable to a sphincter-saving procedure (SSP), the lower third of the rectum is of debate in this respect. Small tumours (T1) in the lower third can be treated by peranal local excision. Low grade tumours with a T2 or T3 stage located above 3 cm from the dentate line are treated by SSP. There is still a place for for advanced tumours (T3 and T4) below 5 cm from the anal verge, in case of deficiency of the anal sphincter, and when the sphincter complex is infiltrated by the tumour. Preoperative staging measures are essential for patients selection in relation to height of the tumour above the anal canal, depth of tumour invasion into the rectal wall, and presence or absence of regional lymph node metastases. Biology of rectal cancer and its implication on surgery, preoperative staging of rectal cancer, technique and results of the main three surgical options, and the advent of laparoscopy are discussed in this article.

[Laparoscopic cholecystectomy in morbid obesity]

In the early days of laparoscopic cholecystectomy (LC) morbid obesity was considered a relative contraindication for this procedure. With increased experience the procedure has been used in obese patients too. To evaluate the influence of morbid obesity on feasibility and outcome of LC, we performed a prospective study in 136 patients in whom LC was attempted between January 1991 and January 1992. Conversion to open cholecystectomy was necessary in 26 cases (19%). The remaining patients were divided into two groups. Group 1 consisted of 92 normal or slightly obese individuals, whereas 18 morbidly obese patients were included in group 2. Intraoperative problems (42% vs 61%) and postoperative morbidity (2% vs 11%) were less frequent in group 1, although not statistically significant. There was no difference in operating time (median for both groups: 110 minutes) and length of hospital stay (4 days). The incidence of late complications (3% vs 6%) was similar. We conclude that LC in morbidly obese patients, as in open surgery, is technically more demanding than in normal individuals. The operative risk was elevated (p < 0.05) as evidenced by a tendency to higher intra- and postoperative complication rates. Cholecystolithiasis in morbidly obese patients is a good indication for LC in the hands of well trained laparoscopic surgeons who are ready to convert to open surgery if problems arise.

[Low anterior resection versus rectum amputation for treatment of rectal cancer]

In the controversy whether abdominoperineal resection of sphinctersaving resection is more radical for the treatment of lower rectal cancer, 77 consecutive patients with rectal cancer were retrospectively analysed. All resections were curative. 40 patients underwent a low resection and 37 patients an abdomino-perineal resection. Both groups were comparable with regard to age, sex and especially tumor-stage. The crude 5-year survival-rates were 52.5% in the resection group and 54.1% in the amputation group, respectively. The patients with a carcinoma located within 5-10 cm from the anal verge were of special interest. The crude 5-year survival-rates in these special subgroups were 61.9% for the sphinctersaving procedure and 61.5% for the amputation group, respectively. We conclude that the choice of surgical procedure does not influence the prognosis in rectal cancer, in particular, sphinctersaving resection does not worsen the prognosis. Therefore, whenever technically possible, the sphincter-saving resection should be chosen to cure rectal cancer.

[Status of portal perfusion in colorectal cancer. Swiss Study Group for Clinical Cancer Research]

533 patients with diagnosis of operable colorectal carcinoma were randomized to receive either a single course of portal infusion with Mitomycin-C (MMC) and 5-Fluorouracil (5-FU) starting immediately after operation, or no adjuvant treatment. Of these, 505 (94%) were evaluable. Over the median follow-up of 8 years, the adjuvant therapy reduced the risk of recurrence by 22% (Hazard ratio = 0.78%, 95% CI 0.61-0.99; P = 0.045). The relative reduction of relapse on death was similar in all subgroups (i.e. nodal status, localization). However, adjuvant portal chemotherapy proved to be most efficient in the subgroups of patients with tumor involvement of the regional lymph nodes (Dukes C) and of patients with colon cancer. Analysis of the pattern of relapse showed that most of the difference in overall and disease-free survival is to be attributed to a consistent reduction of all kinds of tumor recurrences (i.e. local relapses, liver metastases and/or other distant metastases) in the treated group, rather than to liver relapses alone. We conclude therefore, that part of significant benefit obtained for patients with operable colorectal carcinoma treated with a single course of adjuvant chemotherapy via the portal vein might be due to the additional systemic effects of the portal chemotherapy and further study of perioperative treatment with and without prolonged chemotherapy appears worthwhile.

Laparoscopic liver resection in the Large White pig--a comparison between waterjet dissector and ultrasound dissector

Resection of 16 liver lobes was successfully undertaken laparoscopically in anaesthetised Large White pigs. These animals proved to be suitable for the instruments used in human laparoscopic procedures. It was planned to undertake a comparison between the waterjet and ultrasound dissectors, but this proved impossible because of the development of a thick intraabdominal mist during dissection with the waterjet dissector. The ultrasound dissector was effective in dissecting the intraparenchymal hepatic structures, especially the portal vein and the hepatic vein. These blood vessels were safely secured with endoclips, while bleeding points on the resection surface were coagulated with an argon beam coagulator. The liver specimens removed were approximately 75 g in weight. All ultrasound-dissected animals survived for 10 days. Post-mortem evaluation showed two cases of wound infection, one case of subphrenic abscess and two cases of biloma. Our results emphasise the potential of laparoscopic resection techniques for formal or at least peripheral liver resections in humans.

[Secondary peritonitis after negative computerized tomography in blunt abdominal trauma]

Diagnostic peritoneal lavage has widely been replaced by emergency sonography in the evaluation of blunt abdominal trauma. CT is generally performed in cases without major hemodynamic instability in order to define non-operative treatment of injuries of the parenchymatous organs or to precise the extension of retroperitoneal, spinal and pelvic lesions. Despite the good results of this method for the mentioned indications, the low sensitivity of CT for lesions of hollow viscus should not be forgotten. We report 3 cases of lesions of the small bowel (2 perforations and 1 mesenteric lesion with ischemic bowel wall) which were not visible, even retrospectively, at the CT. Despite discrete clinical signs, these lesions were only diagnosed at the stage of obvious secondary peritonitis. These cases should remind us the limits of CT in the evaluation of abdominal visceral lesions in blunt trauma.

[Diagnostic surprises in apparently inflammatory masses of the right iliac fossa]

Most patients presenting an inflammatory mass of the right iliac fossa have a medical history suggestive of an acute appendicitis the weeks before and further investigations will confirm the diagnosis of an appendicular abscess. During the last 2 years, we have investigated and treated seven adults presenting such a mass. In a diagnostic purpose, but in way to treat the suspected abscess in the acute phase with a percutaneous drainage too, we have performed a CT of the abdomen and of the pelvis in every case. Only 3 of 7 patients had in fact a true appendicular pathology. One patient had a cecal diverticulitis with severe peri-diverticulitis, 3 other patients had a malignant lesion developed from a small intraluminal tumor but with a wide extension outside the limit of the cecum. These examples show that careful investigations are mandatory in all cases of apparent inflammatory mass of the right iliac fossa.

Pattern of recurrence in rectal carcinoma: implications for the design of (future) studies on adjuvant therapy

255 patients who underwent potentially curative surgical treatment for rectal carcinoma at the Cantonal Hospital Aarau from 1981 to 1989 have been followed up and the results analysed for overall survival and the timing and occurrence of local and distant recurrence in relation to the initial tumor stage. The patients had received standard surgical treatment for rectal carcinoma with the exception of 28 patients who had been randomized to the treatment arm of SAKK protocol 40/81 and were given perioperative adjuvant portal chemotherapy. 10 patients with large fixed tumors had preoperative radiation therapy. In UICC stage I most patients were cured by surgery alone, local recurrence as rare, and distant metastases appear in about 10% of pT2. cases. In stage II about one fifth of the patients developed a recurrence with one third of them having only local recurrence, and two thirds having either combined local and distant recurrence or distant recurrence alone. The small subgroup of pT4 pN0 had a very poor prognosis with early occurrence of distant metastases. In stage III the actuarial five-year survival was 25%, 60% of stage III cases had pN1 nodal disease. No patient with pN2-3 disease was alive after five years follow-up. The overall risk of distant metastases in stage III was 64%. Local recurrence rate was highly dependent on the pT-stage.(ABSTRACT TRUNCATED AT 250 WORDS)

[Whipple's operation for tumors of the pancreatic head and periampullar area]

Between 1986 and 1991 35 partial duodenopancreatectomies have been performed in the Clinic for visceral surgery of the University of Berne. 17 for adenocarcinoma of the pancreas and 18 for miscellaneous malignant or semimalignant pathologies such as ampullary or duodenal carcinomas, cystadenomas and distal bile duct carcinomas. The mortality was 5%. Postoperative complication was observed in 50% of cases. Leak at the pancreaticojejunal anastomosis was the most common surgical complication but healed under conservative treatment with somatostatin within few days in 5 of 6 cases. The median survival for patients with adenocarcinoma of the pancreas is 550 days, for patients with other pathologies 1200 days with some long-term survival in ampullary carcinomas. These results show on one hand that this kind of surgery can be realized with acceptable morbidity and mortality rate, on the other hand that further clinical trials in systemic adjuvant treatment are indicated especially in pancreatic cancer to improve the disappointing long-term results.

A rare complication of the use of a finger cot to protect the cuff of a tracheal tube during nasotracheal intubation

Some anesthetists in Switzerland and elsewhere use a finger cot to protect the cuff of the endotracheal tube during nasotracheal intubation. In the presented report the finger cut was lost during the procedure and the patient presented 3 months later with a lateral neck mass. The finger cot was found within that mass at exploration. Apart from the other potential risks of this manoeuvre, this severe complication should incite caution against the practice described above.

[Massive hemorrhage from presacral veins during resection of the rectum]

During the last 53 abdominoperineal amputations of the rectum for carcinoma, we had to control 5 massive hemorrhages. 4 of which were due to a lesion of the presacral venous plexus and caused a mean blood-loss of 4750 ml. During a "normal" Mile's operation our 49 other patients lost an average of 1750 ml (median 1200 ml) of blood. The negative effects of this type of complication and the following need for massive transfusion is not only local, circulatory and pulmonary, but also due to the immunodepressive effects of massive transfusion. We describe the different methods of control of these hemorrhages and insist on the advantage of using sterilised metallic thumbtacks, a method which was described 1984 by doctor Wang Qinyao of Shanghai.

[The pattern of recurrence of T3 rectum cancer]

Rectal carcinoma is one of the most common tumors of the GI-tract. At the time of initial treatment the majority of our patients had a stage T3 tumor. In order to contribute to the development of new guidelines for adjuvant therapies we analysed the patterns of recurrence in the patients operated with curative intention in our institution between 1981 and 1989. The pattern of recurrence shows that every fifth patient could benefit of a local measure to reduce local recurrence and that every second patient with positive nodal histopathology could benefit of a systemic adjuvant chemotherapy.

[Transarticular amputation at the knee in peripheral arterial occlusive disease. Very positive experiences after routine use of the Klaes and Eigler technique]

In a retrospective study we compare our experience with the through-knee amputation in peripheral vascular disease. In the first 15 patients we used an amputation technique with circular incision. In about 50% of these patients we observed a delayed wound healing or they needed a reamputation to a higher bony level. In the 17 following patients we used the amputation technique described by Klaes and Eigler, using a posterior myocutaneous flap to cover the condyles. Only one of these patients needed a reamputation and another had a secondary wound healing. We conclude that the technique of through-knee amputation described by Klaes and Eigler is better adapted for patients with peripheral vascular disease.

[Intra-abdominal infections]

50% of the patients admitted for acute abdominal pain have an infectious intra-abdominal disease, most of them an appendicitis, a cholecystitis or a diverticulitis. These infectious diseases are due to a noninfectious lesion of the wall of an intestinal organ. The defense mechanism and the bacterial synergism limit the number, nature and local extension of the multiple micro-organism, producing a strong selection. For the treatment, antibiotics play an important adjuvant role. The main question in all cases is to determine if the cure of the wall lesion is necessary. Furthermore, it is important to choose the ideal time to do it, according to the extension of the lesion, the immunocompetence and the physiological state of the patient. The advantages and inconveniences of an early or late operation have to be weighted. Some special aspects of appendicitis, cholecystitis and diverticulitis are discussed.

[Sonographic criteria of acute acalculous cholecystitis.Critical observation of the clinical records of sedated, ventilated and parenterally nourished patients]

After comparing the classical ultrasonographic findings of acute acalculous cholecystitis with our findings on 24 clinical and sonographic followed acute care unit patients, we have to pay attention to the possible reversibility of such phenomena as increased gallbladder wall thickness, low-level echo surrounding the gallbladder and sludge. In our experience, there is no correlation between a negative cholecystokinin stimulation test and an acute acalculous cholecystitis.

Doxium 500 in chronic venous insufficiency: a double-blind placebo controlled multicentre study

The aim of this double-blind placebo-controlled study was to evaluate the therapeutic efficacy of Doxium in chronic venous insufficiency (CVI). 225 patients were treated randomly for 4 weeks with 1.5 g (3 capsules/day) of Doxium or placebo. The evolution of the leg oedema was determined by measuring calf and ankle circumferences. Pain and discomfort were assessed by visual analogue scale. The results show that at the end of the trial, all the examined parameters (leg oedema, pain, day and night cramps, discomfort, heavy legs, paresthesia and restless legs) were significantly more improved in the Doxium group than in the placebo group: the leg volume was diminished by 3.8% in the Doxium group compared to 1.2% in the placebo (p less than 0.005). The overall assessment by the physicians showed an improvement in 82% of the Doxium-treated patients compared to 42% of the placebo group (p less than 0.0001). The tolerance of the treatment was comparable in both groups.

[Blood transfusions and prognosis following curative resection of colorectal cancer: is there an association?]

More recently a number of retrospective analyses in rather ill defined patient populations demonstrated an association between perioperative blood transfusion and recurrence after curative resection of colorectal cancer. In the randomized trial (SAKK 40/81) (adjuvant cytotoxic intraportal infusion versus no further treatment) we evaluated the transfusion status in a well defined, prospectively documented and controlled patient population. Of 457 patients, 353 (77.2%) received either pre-, intra- or postoperatively blood transfusions. After a median follow-up of 4 years, the transfused patients developed significantly more recurrences (38.2%) than patients without blood transfusions (23.1%), the death-rate being 33.7% versus 23.0%, respectively. Patients without transfusion but treated with adjuvant intraportal chemotherapy are strikingly doing better (10.5% recurrences) than patients with perioperative blood transfusion not having an adjuvant treatment (44.5% recurrences).

[The significance of omentum-plasty for early detection of local recurrence following abdomino-perineal rectum amputation in cancer]

In a prospective study activated in October 1986 feasibility of omentoplasty after abdomino-perineal resection for cancer and implications of this procedure on early diagnosis of local recurrence were assessed. In 22 of 32 patients abdomino-perineal resection was completed by obliteration of the pelvi-perineal deadspace with pedicled omentum. CT-scans 6 months and 1 year postoperatively were analyzed in relation to diagnosis or exclusion of local recurrence. In 6 patients (27%) local recurrence was diagnosed in CT-scan and confirmed clinically (no false positive result). In 11 patients (50%) local recurrence could be excluded with high probability. In 5 patients (23%) uncertainty remained about exclusion of local recurrence.

Rheological properties of human blood plasma--a comparison of measurements with three different viscometers

Human plasma viscosity was measured in capillary tube, cone-plate and Couette viscometers. The measurement of the viscosity at very low shear rates showed that plasma is a non-Newtonian fluid with a pseudoplastic rheological behaviour. The importance of this phenomenon for the microcirculation is discussed.

[Transmission of the anterior chamber pressure to the center of the vitreous body and to the posterior pole of the eye of the miniature swine. Measurement of isovolumetric and direct pressure]

Experimental variations of the anterior chamber pressure (P.I.C.) are transmitted at about 300 ms to the middle of the vitreous. The response time to a sudden experimental increase in P.I.C. to the centre of the vitreous is variable and depends essentially on the control intra-ocular pressure: the more it is raised the shorter the response time. The pressure in the centre of the vitreous (P.I.V.) has a pulsatile character probably due to transmission of arterial pulsation. The higher the intra-ocular pressure the greater the amplitude of these pulsations. Recording of P.I.V. close to the surface of the retina show abrupt falls despite the fact that the P.I.C. and systemic arterial pressure remain stable. These results are discussed in relationship to autoregulation of the retinal circulation and the physiopathology of glaucoma.

Editorial: Red cell ageing and death

To obtain red cell populations of increasing mean age erythropoiesis was arrested through continuous actinomycin treatment or maintained transfusion polycythemia in mice and rats respectively. The parameters studied included cell indices, enzyme activities and rheological characteristics. Further, the life-span of aged cells was compared to normal, and the sequestration site was determined. Mice erythrocytes, like those of rats, exerienced a continuous decrease in MCV1, an early rise in MCHC, and late MCH reduction. In ageing rat erythrocytes the activities of HK, GR and 6-PGD did not fall below the normal range during the first 9 tenths of the potential life-span. On the other hand, a borderline reduction of PK activity was found, and the activity of G-6PD underwent a steady though unimpressive decrease to 70% of the physiological average. Aged erythrocytes, forced through 15-mum capillaries differed in apparent viscosity from reticulocytes and normal cells by a factor of 1.31 and 1.16, respectively. Destruction of senescent cells was predominantly confined to the spleen, and prolonged erythrocyte survival followed splenectomy.

Measurement of foot artery blood pressure by micromanometry in normal subjects and in patients with arterial occlusive disease

Blood pressure was measured continuously in the posterior tibial or dorsalis pedis arteries using an isovolumetric system (steel cannulas of 0.18 mm, external diameter). The systolic values in the ankle arteries of 13 normal subjects at rest (154.3 +/- 22.3 mm Hg) exceeded the systolic arm pressure (128.9 +/- 20.1 mm Hg, P less than 0.001), while diastolic values (69.9 +/- 8.7 mm Hg) were not significantly different from the arm pressure. In 13 patients with arterial occlusive disease (AOD) the dicrotic notch, normally situated close to the footpoint of the downslope, was either displaced upward or abolished. Both mean systolic and diastolic values (94.9 +/- 35.9 mm Hg and 62.5 +/- 18.5 mm Hg, respectively) and also mean pressure amplitude were reduced compared to the corresponding arm values (158.5 +/- 28.2 mm Hg and 87.7 +/- 6.0 mm Hg, respectively, all P less than 0.001). Comparison between the systolic pressure values measured by micromanometry and by an indirect technique using Doppler ultrasound showed a good correlation (r = 0.87). During postocclusive reactive hyperemia, the initial pressure values were markedly diminished in normal subjects and reached control values within 40 sec. In patients with AOD, however, this reduction in pressure was more pronounced and prolonged. Flow measurements using plethysmography showed flow diversion from the foot to the calf as long as pressure values ranged below 40 mm Hg. This almost painless method appears useful for experimental and diagnostic studies in low pressure areas of the peripheral circulation.