Models for investigating the aetiology of cerebral arterial spasm: comparative responses of the human basilar artery with rat colon, anococcygeus, stomach fundus, and aorta and guinea-pig ileum and colon.

1 The pharmacological similarity between human basilar artery and a number of isolated tissues (rat colon, anococcygeus, stomach fundus and aorta and guinea-pig ileum and colon) has been assessed during investigations of the aetiology of cerebral arterial spasm. 2 The responses of each of the six tissues to human normal and abnormal cerebrospinal fluid (CSF) and to human serum were compared with those of the human isolated basilar artery. 3 These studies revealed the presence of a vasodilator factor in CSF from subarachnoid haemorrhage patients and several tissues may be of use for further work in identifying the vasoactive substances in CSF. 4 No tissue displayed exactly the same spectrum of biological reactivity as the human basilar artery. The rat stomach fundus showed the closest similarity and was further studied for similarities in drug-induced responses. 5 The rat stomach fundus, like the human basilar artery, was contracted by 5-hydroxytryptamine, prostaglandin F2alpha and histamine and relaxed by dopamine. However, noradrenaline relaxed the fundus but contracted the basilar artery.

Automated measurement of tumour extent in patients with colorectal liver metastases from X-ray computed tomography.

Tumour burden is a significant prognostic factor in patients with colorectal liver metastases, and can be staged according to percentage hepatic replacement (PHR), but accurate measurements of PHR are difficult to obtain. We have used an automated computerized technique to isolate tumour and measure PHR from computed tomography images of 22 patients. Tumour identification was achieved by establishing local histogram-based thresholds at liver-tumour boundaries displaying clear bimodal histogram distributions. There was a significant association between measured PHR and independent visual estimates of PHR stage defined in quartiles (p less than 0.001). When the measured value of PHR differed from the PHR stage, the visual estimate was always higher. The accuracy of PHR measurement was assessed on stimulated liver computed tomography images. It seems likely that visual estimates of PHR from computed tomography images tend to overestimate tumour extent. The automated technique is probably more accurate and will be useful for assessing and monitoring patients.

Cannulation of the portal vein for cytotoxic liver perfusion in colorectal carcinomas: an alternative approach.

Cytotoxic liver perfusion via the portal vein has been used with some success as an adjuvant to surgery for colorectal carcinoma. We have used an alternative method of cannulating the portal vein at the time of operation and support the use of this method as well as the use of short-term 5FU infusion via the portal vein as being safe and of low systemic toxicity.

Endoscopic transanal resection (ETAR) of colorectal strictures in stapled anastomoses.

Anastomotic strictures complicating colorectal anastomoses can be difficult to treat. Endoscopic transanal resection (ETAR) using cutting electrocautery has been described for benign and malignant polypoid rectal lesions, but is not a well-recognised method of treating anastomotic strictures. There are possible theoretical risks to limit the effectiveness of this method in stapled anastomoses. We report five patients with stapled colorectal anastomotic strictures all treated successfully without complication by ETAR, and recommend this treatment option.

Resection of liver metastases from a colorectal carcinoma does not benefit the patient.

This paper presents arguments for and against the motion that 'Resection of liver metastases from colorectal carcinoma does not benefit the patient'. The case for this proposition is summarised as follows: survival after resection of small metastases is not markedly different from the natural history of similar tumours; patients with metastases apparently localised to one area of the liver are uncommon, and thorough investigation further reduces the proportion of such patients; the operative mortality of liver resection has a significant adverse effect on survival after resection, and may cancel out the benefits of surgery, and finally the alternative non-operative methods of treating these patients may offer similar benefits to resection. The counter argument is simple: for a patient with liver metastases the only hope of eradication of liver disease lies in surgical resection. If this can be achieved then the prognosis is as good as for a similar primary tumour without liver metastases.

Laparoscopic cholecystectomy in Leicester: an audit of 555 patients.

Laparoscopic techniques have revolutionised the surgical approach to cholecystectomy, even though there have been no published randomised controlled trials to demonstrate the safety of this approach. We present an audit of 555 patients offered laparoscopic cholecystectomy. In all, 54 patients (9.7%) were converted to an open procedure. Peroperative cholangiography (POC) was attempted in 190 cases (34.2%) and achieved in 141 (25.4%). Major complications occurred in 26 cases (4.7%) including 5 (0.9%) deaths, two of whom had major pre-existing morbidity. There was one common bile duct (CBD) injury (0.18%). There were 30 patients (5.4%) found to have CBD stones, 27 of which were cleared at ERCP, and three converted to open exploration. Cholecystectomy by any route is a major operation and we conclude that careful case selection remains imperative. However, morbidity is favourable compared with open cholecystectomy, and comparable with other reports using the laparoscopic technique. Our experience of CBD injury (0.18%) is also acceptable compared with the risk of injury during open cholecystectomy. There were 312 patients (56.2%) who did not undergo perioperative CBD imaging with ERCP or POC and three of these developed early symptomatic retained stones. This group requires further follow-up.

A comparison of methods to measure the percentage hepatic replacement with colorectal metastases.

The percentage hepatic replacement (PHR) with liver metastases has been recognised as an important factor for patient management, prognosis, and clinical trial evaluation. The PHR can be assessed by various methods including ultrasound, radioisotope, or computed tomography (CT) imaging, or by inspection and palpation at laparotomy. We report a prospective study comparing these methods of PHR assessment in 56 consecutive patients with colorectal liver metastases. When all four methods were used complete agreement was achieved in only 35% of cases (9/26). The three imaging techniques agreed in only 37% of cases (14/38). Overall, the correlation between different methods was poor with a tendency for surgery to underestimate the PHR. However, CT and surgery agreed in 81% of cases (21/26), and CT gave a higher estimate than surgery in each of the other five patients. With such variability in the estimates of PHR derived from these different techniques, consideration must be given to which technique is used. It is concluded that CT is probably the most accurate for PHR assessment at present.

Endometriosis--the problems of intestinal obstruction.

Endometriosis is a relatively common condition in women of child-bearing age, and coincidental intestinal serosal involvement is frequently recognised. However, intestinal obstruction, although reported, is rare. We report what we believe is the first case with synchronous ileo-caecal and rectosigmoid obstructing endometriomas. Endometriosis as a cause of bowel obstruction is discussed and in particular the differential diagnosis from Crohn's disease and malignancy.

The role of chemotherapy in the treatment and prophylaxis of colorectal liver metastases.

Although colorectal liver metastases are a common occurrence, the role of chemotherapy in the management of this condition remains controversial. This article reviews the value of chemotherapy in the treatment and prevention of colorectal liver metastases. Systemic chemotherapy is of no proven benefit in terms of patient survival. Regional approaches to therapy are only a little more encouraging, although an objective view is difficult due to the lack of suitable randomized controlled trials and the difficulty in comparing results of different studies. More recent attempts to enhance regional therapy with degradable starch microspheres have theoretical advantages but need further clinical evaluation. Ultimately, more effective means of controlling overt or occult extrahepatic disease are also required when treating established liver metastases. The use of adjuvant intraportal chemotherapy for the prevention of liver metastases is more encouraging, however, and appears likely to have an important role.

Management of a patient with Wilms's tumour extending into the right heart chambers: a case report and a review of other published reports.

Wilms's tumours that extend by direct intravascular spread into the right side of the heart are rare. A case of such a tumour was diagnosed by ultrasound. A one stage resection was performed on cardiopulmonary bypass and with profound hypothermic circulatory arrest. It was followed by adjunctive chemotherapy and radiotherapy. The child was alive and tumour free 18 months later. A review of 17 other similar cases indicated that multimodal treatment is justified in patients with extensive intravascular spread of Wilms's tumours.

Morbidity in gynaecological day-case surgery. A comparison of two anaesthetic techniques.

The effectiveness of fentanyl, given as part of the anaesthetic technique, in reducing abdominal pain following outpatient gynaecological surgery has been examined. It was found to reduce significantly the frequency of abdominal pain in the period extending from discharge from hospital to the first evening, while not compromising surgical conditions nor increasing the frequency of other post-operative sequelae such as nausea and vomiting.

Treatment of rectal prolapse by sphincteric support using silastic rods.

The use of silastic perianal rings to control rectal prolapse in the elderly has been reviewed. Forty-one patients were treated over a 6 year period by a total of 52 operations. Their mean age was 80 years and there was no operative mortality. Prolapse was adequately controlled in 71 per cent of patients, and a further three patients had no recurrence despite failure and removal of the ring. The results of this procedure are inferior to those obtained by abdominal operations for rectal prolapse, but deserve serious consideration in those elderly patients who may be unfit for laparotomy.

Responses of human and baboon arteries to prostaglandin endoperoxides and biologically generated and synthetic prostacyclin: their relevance to cerebral arterial spasm in man.

1 Isolated strips of human or baboon basilar, middle cerebral, vertebral or common carotid arteries were set up in an isolated organ bath or in a superfusion cascade system. 2 These arteries relaxed to prostacyclin but contracted to prostaglandin endoperoxide (PGH2). 3 Human and baboon isolated arteries also generated prostacyclin from exogenous endoperoxide (PGH2). 4 Human arteries generated prostacyclin 36 h post-mortem but not 40 h post-mortem. The biologically generated prostacyclin relaxed the basilar artery and overcame the contractile effects of PGH2. 5 Thromboxane A2-like activity generated during human platelet aggregation by arachidonic acid caused contractions of the human basilar artery. 6 Prostacyclin reversed contractions of human basilar arteries caused by an unidentified vasoconstrictor factor in cerebrospinal fluid obtained from patients with cerebral arterial vasospasm after subarachnoid haemorrhage following rupture of cerebral arterial aneurysms. 7. The above vasospasm may be due at least in part to disordered physiological control of the calibre of cerebral arteries caused by diminished synthesis of prostacyclin.

Relationship between presence of vasoconstrictor activity in cerebrospinal fluid and time after subarachnoid haemorrhage from rupture of cerebral arterial aneurysms.

The relationship between clinical condition and vasoconstrictor factors in cerebrospinal fluid was studied in 19 patients for up to six weeks after subarachnoid haemorrhage. Vasoconstrictor activity was assayed biologically. Sixteen of 19 patients improved as vasoconstrictor activity declined; this pattern was not significantly influenced by surgery. Serial angiography was performed on three patients and a qualitative relationship was shown between arterial dilatation, clinical improvement, and reduced pharmacological activity.

Prospective randomized controlled trial of hepatic arterial embolization or infusion chemotherapy with 5-fluorouracil and degradable starch microspheres for colorectal liver metastases.

Survival benefit from hepatic artery embolization (HAE) or hepatic arterial infusion chemotherapy (HAI) in patients with unresectable colorectal liver metastases has not previously been assessed in a randomized controlled trial. Sixty-one patients were randomized, 20 to receive no treatment, 22 to receive HAE, and 19 to receive HAI with 5-fluorouracil and degradable starch microspheres. Both treatments were acceptable to the patients in terms of low treatment morbidity rate. Median survival from diagnosis of metastases was 9.6 months for controls, 8.7 months for the HAE group and 13.0 months in the HAI group. There was no apparent survival benefit for the HAE group. The increased survival in the HAI group was observed in all the subgroups analysed but failed to reach statistical significance. The greatest observed benefit was achieved in the subgroup with less than 50 per cent hepatic replacement with tumour at presentation (median survival from diagnosis 10.0 months for controls, 10.2 months for HAE and 23.6 months for HAI); 36 per cent of patients developed extrahepatic disease recurrence. No significant benefit has been shown from either HAE or HAI, but a more carefully selected group of patients with only low volume hepatic disease may benefit from HAI therapy.

An association between parameters of liver blood flow and percentage hepatic replacement with tumour.

The extent of hepatic replacement with tumour is a significant prognostic factor in patients with liver metastases. Measuring the percentage hepatic replacement (PHR) accurately is difficult, but is important for both patient management and clinical trial evaluation. This study correlates haemodynamic indices obtained by dynamic liver scintigraphy (DLS) with estimates of PHR made from isotope scan, ultrasound, CT scan and laparotomy in 45 patients with established colorectal liver metastases and 21 controls who also underwent DLS. There was a significant reduction in the mesenteric fraction (MF) in the group of patients with metastases compared to the controls (P less than 0.001), and also a significant trend for progressive reduction in the MF with increasing PHR. A significant rise in an index of total hepatic arterial blood flow was also demonstrated with increasing PHR. These results are important with current interest in regional hepatic arterial therapy, and may prove of clinical value for prediction or monitoring of response to therapy.

A preliminary assessment of atracurium, a new competitive neuromuscular blocking agent.

Atracurium besylate, 2,2'-(3,11-dioxo-4,10-dioxatridecylene)-bis-[6,7-dimethoxy-1-(3,4-dimethoxybenzyl)-2-methyl 1,2,3,4-tetrahydroisoquinolinium] dibenzenesulphonate is a potent non-depolarising (competitive) neuromuscular blocking agent in the cat, monkey, dog and anaesthetized man. In man, it caused complete paralysis of the tetanic response of the adductor pollicis muscles at doses of 0.2 mg/kg. Blockade was of medium duration with rapid spontaneous recovery, and was readily reversed by neostigmine. The electrocardiogram, heart rate, arterial blood pressure and central venous pressure were virtually unchanged following doses of 0.2-0.4 mg/kg. Intubation was readily accomplished in 1.5-2 min after administration of 0.25-0.3 mg/kg.

A comparison of three indices of relative hepatic perfusion derived from dynamic liver scintigraphy.

Data from dynamic radiocolloid liver scintigraphy (DLS) have been analysed to calculate three indices of relative arterial to total hepatic perfusion. Ninety subjects have been studied, comprising 21 normals, 62 patients with metastatic liver disease and 7 patients with cirrhosis. Correlation coefficients above 0.81 were found in all patient groups between an index based on rates of liver uptake (the hepatic perfusion index, HPI) and a method based on quantitative liver uptake (the mesenteric fraction, MF). A further method employing the spleen to model arterial inflow (hepatic arterial ratio, HAR) had less agreement with both HPI and MF, with correlation coefficients below 0.76. Posterior images have previously been used to calculate HAR, and greater errors are expected in HAR from the anterior images acquired in this study. Receiver operating characteristic analysis showed that the diagnostic performance of HPI and MF indices in metastatic disease were not significantly different. For anterior image data analysis both HPI and MF were superior to HAR.