Curative rectal cancer surgery in a low-volume hospital: a quality assessment.

AIMS: Hospital volume or caseload is often used as a surrogate measure for quality of care in rectal cancer treatment. The aim of this study was to assess outcome in a low-volume hospital and secondly to examine the impact of surgeon volume on the results. METHODS: A retrospective review of 131 patients' charts identified 102 patients receiving apparently curative resections for rectal cancer in the period 1993-2002. Our study population did not differ significantly from the national average except for shift towards more advanced Dukes stage (p=0.00) and a higher rate of node positive patients at time of diagnosis (p=0.00). RESULTS: There were no significant differences from the national outcome results, neither in perioperative mortality or complications, nor 5-year survival or local recurrences. Thirteen different on-staff surgeons performed rectal cancer surgery in our hospital in the decade, and median annual caseload was four. We detect a difference in 5-year survival when grouping the surgeons by annual caseload, but the significance is inconclusive. It is, however, interesting that in 85% of the resections, two or more certified gastrointestinal surgeons with specific training were involved. A relatively high number (9%) of discrepancies between the Norwegian Rectal Cancer Registry (NRCR) database and the local hospital database were identified. CONCLUSION: Adequate results for surgical outcome can be achieved in a low-volume hospital. Surgeon volume showed inconclusive impact for our results of outcome. A local quality initiative is justified in addition to national registries.

Gut perforation caused by biliary endoprosthesis.

Two cases are reported of perforation of the gut caused by biliary endoprosthesies in the three-year period 1993-1995. The first patient was an 81-year-old man who had perforation of the terminal ileum caused by a straight 10 French/7 cm stent which had been dislodged from the bile duct; he underwent laparotomy but did not recover. The second patient was an 86-year-old man who had perforation of the sigmoid colon caused by a straight 7 French/5 cm stent left in the duodenum during a stent exchange procedure; he was successfully treated laparoscopically. Two cases of gut perforation in a three-year period is a rather high rate of this rare complication of placement of biliary endoprostheses.

The medullary dorsal reticular nucleus facilitates pain behaviour induced by formalin in the rat.

The influence of the dorsal reticular nucleus (DRt) on pain behaviour during the formalin test was studied in the rat by lesioning the nucleus through local application of electrical current or quinolinic acid. Animals in which the DRt was lesioned ipsilaterally to the paw injected with formalin spent less time in focused (licking, biting or scratching the injected paw) and total (focused pain behaviour plus protection of the injected paw during movements) pain behaviour, and showed paw-jerks less frequently than non-lesioned animals in both phases 1 and 2 of the test. Animals in which the DRt was lesioned contralaterally to the injected paw presented a decrease in total pain behaviour and number of paw-jerks only during phase 2. The number of superficial (laminae I-II) and deep (laminae III-VI) spinal dorsal horn cells expressing the c-fos proto-oncogene 2 h after subcutaneous injection of formalin was reduced by 34% and 50%, respectively, in animals with an ipsilateral DRt lesion as compared to non-lesioned rats. No differences in c-fos expression were observed after lesioning the DRt contralateral to the formalin injection. The results indicate that the DRt is involved in the facilitation of nociception during the formalin test by enhancing the response capacity of dorsal horn neurons to noxious stimulation. It is suggested that the pronociceptive action of the DRt is mediated by the reciprocal connections it establishes with the spinal dorsal horn.

Differential effects of activation of lumbar and thoracic 5-HT2A/2C receptors on nociception in rats.

The role of 5-HT2 receptors in nociceptive behaviour of rats was investigated using spinal administration of the 5-HT2A/2C receptor agonist (+/-)-2,5-dimethoxy-4-iodoamphetamine (DOI), the 5-HT2A/2C antagonist ketanserin and the glutamate receptor agonist NMDA. Nociceptive behaviour was scored after injections at upper thoracic or lumbosacral levels. DOI (0.1-10 mM, 15 microl) administered at the upper thoracic level induced pain-like behaviour in a dose-dependent manner and a long-lasting motor depression at the greatest dose. At the lumbosacral level a similar dose-dependent pain-like behaviour was observed, but it was less pronounced. Motor depression was not observed at any dose. Ketanserin injected before DOI blocked both nociceptive and motor effects. Stimulation of both NMDA and 5-HT2A/2C receptors had a mutually potentiating effect. The present results show that the effects of DOI were more pronounced at the upper thoracic than at the lumbosacral level. This is possibly caused by the difference in 5-HT2A/2C receptor density at the two levels. The motor depression induced by the greatest dose of DOI given at the upper thoracic level appears to mask the pain-like behaviour. The nociceptive behaviour seen after DOI injection is further increased following co-injection of NMDA.

Lumbar catheterization of the spinal subarachnoid space in the rat.

The method commonly used for catheterization of the lumbar subarachnoid space in the rat implies inserting the catheter through the atlanto-occipital (A-O) membrane and moving the catheter caudally along the spinal cord. The method is associated with a considerable morbidity. A method for direct catheterization of the lumbar subarachnoid space was therefore developed. Major surgery was avoided by using a catheter-through-needle technique. Of 32 rats, none died. There were no signs of neurological disturbances, and all animals gained weight as normal the first week after implantation. Data from rats catheterized by the A-O method were used for comparison. Of 40 animals, 2 died, 11 showed signs of neurological disturbances, and the mean weight was reduced during the first week after catheterization. The two groups of animals showed different behavioural responses to intrathecal injection of N-methyl-D-aspartate (NMDA, 0.1-1.6 mM, 15 microliters) which is thought to stimulate afferent pathways mediating nociception. Animals with a lumbar catheter showed licking, biting and scratching behaviour in a dose-related manner for concentrations up to 1.6 mM. The animals with A-O catheters showed a maximum level of this behaviour already at 0.4 mM, while 0.5 mM induced convulsions. A possible explanation of this difference in response to NMDA could be a long-lasting pain state in the A-O group, caused by catheter-induced changes in the spinal cord and by the extensive surgery. It is concluded that the direct lumbar catheterization has several advantages compared to the A-O method, decreasing the suffering of the animals, the neurological disturbances and the interference with nociceptive functions of the spinal cord.

Safety of enoxaparin and dextran-70 in the prevention of venous thromboembolism in digestive surgery. A play-the-winner-designed study.

A total of 327 patients were included in a play-the-winner (PTW)-designed study comparing the safety of prophylaxis with enoxaparin and dextran-70 in patients undergoing digestive surgery. In a PTW-designed study the treatment of any next patient will depend on the outcome of the previous one. If successful, the next patient will receive the same treatment. Excessive bleeding, on the basis of specified criteria, severe adverse effects, or occurrence of clinically detected venous thromboembolism was classified as failure. The PTW design allocates most patients to the superior treatment. In this study 200 patients were given enoxaparin and 127 dextran-70. The success rate was 83% in the enoxaparin group and 74.8% in the dextran-70 group (p = 0.05). The survival analysis of 'Number of patients before change in treatment' shows a significant difference in favour of enoxaparin (p = 0.05). Enoxaparin seems to be superior to dextran-70 as a prophylaxis in digestive surgery. The PTW model is a suitable design in such studies.

The role of 5-HT1A and 5-HT1B receptors in spinal nociceptive transmission and in the modulation of NMDA induced behaviour.

The effects on nociception of intrathecal (i.th.) administration of selective 5-HT1A and 5-HT1B agonists were studied in rats. Nociception was evaluated using the tail-flick test with adjustments for tail-skin temperature, the increasing temperature hot-plate test and the scoring of biting and scratching behaviour after i.th. N-methyl-D-aspartate (NMDA). Activation of the spinal 5-HT1A receptor induced an antinociceptive effect in the increasing temperature hot-plate test and produced a dose dependent decrease in NMDA-receptor mediated behaviour. No significant change in nociception measured by either of the nociceptive tests was found after administration of the 5-HT1B agonist. These results support the hypothesis that spinal 5-HT1A receptor activation has an antinociceptive effect, and indicate a possible interaction between the serotonergic and glutaminergic transmitter systems.