Potential serious bias in National Clinical Databases with low degree of reported follow-up.

We identified reasons for the low follow-up rate in the Danish Knee ligament Reconstruction Register (DKRR) and evaluated its influence on the data quality. All 946 primary ACL-reconstructed patients in the Capital Region of Denmark during 2012 were identified in the databases of 8 participating hospitals. We studied the patient files and compared them to figures reported to the DKRR. 92.5% of the operated patients was registered in DKRR. The 1-year follow-up rate reported to DKRR was 33.4%, and 14.5% filled in patient reported outcomes (KOOS and Tegner) at 1 year. Only 65% had actually been invited for follow-up, but among the patients who had been invited 91% were seen. 41% of existing follow-up data was not reported. Contemporary technology and structured motivation should be introduced to increase validity of data in national clinical databases. Follow-up >90% in the DKRR is realistic if patents are invited and reported. The unreported data is potentially a serious bias. It is suggested that data from clinics with low follow-up should not be used in studies involving outcomes based on national databases because of risk of bias.

[Diagnosis and treatment of vesico-intestinal fistula]. / Diagnosticering og behandling af vesikointestinal fistel.

In a retrospective study of 28 patients with vesico-intestinal fistula, the maximal diagnostic latency was eight years. The most common causes were diverticulitis (16 patients) and carcinoma of the colon (4 patients). Recurrent urinary tract infections with pneumaturia and/or faecaluria were found in 23 patients. The diagnosis was most accurately confirmed by cystoscopy and barium enema which showed evidence of a fistula in 20 patients. Patients suffering from diverticulitis were managed with excellent results while surgical intervention in malignancy was associated with brief survival. Diverting colostomy as a sole procedure in patients with infravesical obstruction involves the risk of rectal miction.

The potential difference response of the human gastric mucosa to cimetidine.

The effect of cimetidine on the dynamic transmucosal potential difference (PD) of the normal human gastric fundus was studied, to quantitate the influence of the hydrogen ion on measurements. PD was measured between an intravenous flowing bridge of isotonic NaCl and a perfused intragastric probe by means of two calomel half-cells. The probe was used for luminal infusion of different electrolyte solutions, which at the same time functioned as the mucosal measuring electrode. Cimetidine increased PD -12 mV during NaCl infusion. When gastric acidity was neutralized with isotonic NaHCO3, this change of PD decreased to -5 mV. We conclude that 60% of the PD increase seen after H2 blockade may be explained by the mere disappearance of H+ from the gastric juice, and the other 40% by changes in the gastric mucous membrane. PD decreased progressively as luminal NaCl content was lowered, but this reaction was reversed after cimetidine. These findings may be explained by a twofold decrease of transmucosal permeability to Na+ during H2 blockade.

Direct inguinal herniorrhaphy. A long-term follow-up study.

The cumulated recurrence rates following repair of 365 primary medial inguinal hernias in 297 patients were 13% after 5 years of observation, 19% after 10 years and 23% after 15 years (median observation times). Re-recurrence after repeat herniorrhaphy occurred in 45% of patients over a 10-year period. A more restrictive approach to surgery of direct inguinal hernia is advocated, especially to repair of recurrent hernia.

Electrogenic transport of glucose in the normal upper duodenum. I. Technique and apparent transport constants.

We investigated the electrogenic transport of glucose in the upper part of the duodenum in 11 healthy subjects by means of simultaneous intestinal perfusion of test solutions and measurement of the corresponding potential differences between blood and the duodenal lumen. The technique entailed continuous perfusion and registration of potentials through one single lumen of the probe. The basal potential difference during infusion of 154 mM NaCl was -4.9 +/- 0.5 mV (mean +/- 1 SEM). This was not significantly different from the level obtained during infusion of a standard perfusate composed like plasma: -4.3 +/- 0.5 mV. Perfusion of iso-osmolar solutions containing increasing concentrations of glucose raised the transmucosal potential difference progressively. The relation followed Michaelis-Menten kinetics, from which the apparent transport constants were calculated: Kappm = 53 mM and Vappmax = 9.9 mV. By means of repeated experiments, we examined day-to-day changes of basal potentials and electrogenic glucose transport. No significant differences or systematic variations were found.

Electrogenic transport of glucose in the normal upper duodenum. II. Unstirred water layer and estimation of real transport constants.

The thickness of the unstirred water layer in the normal upper duodenum was measured in 11 healthy volunteers. We used the technique of simultaneous intestinal perfusion and measurement of the corresponding transmucosal potential differences (pd). The unstirred layer was calculated from the half time required to establish an Na+ diffusion potential across this layer. At a flow rate of 17 ml/min the thickness was 351 +/- 13 microns (mean +/- 1 SEM). The level increased significantly as the flow rate was reduced. The results were used to calculate estimates of the real transport constants, which describe the carrier-mediated electrogenic transport of glucose in the normal upper duodenum. Pdrealmax was calculated to be 1.1 +/- 0.15 mV, Jrealmax 6.6 nmol/cm2 X sec, and Krealm 25.8 mM. The origin of the transport-related potential change during glucose absorption was examined. It is suggested that about 60% of the total measured potential response may be attributed to a Na+ diffusion potential across the intestinal unstirred water layer.

Influence of neural blockade and indomethacin on leucocyte, temperature, and acute-phase protein response to surgery.

Body temperature, P-cortisol, P-glucose, P-transferrin, haematocrit and total and differential leucocyte counts were investigated in 24 men undergoing inguinal herniotomy, but otherwise healthy. The patients were randomized to general anaesthesia (GA, n = 8), epidural analgesia (E, n = 8) or epidural analgesia + indomethacin (E + I, n = 8). The rectal temperature rose significantly after surgery, except in the E + I group, and increase in blood granulocytes was significantly less in these patients than in the GA group. Group E showed intermediate changes. P-transferrin changes were similar in all three groups. Glucose and cortisol showed only slight increase in the GA group and constant values in groups E and E + I. It is concluded that prostaglandins may play a role in mediating the surgical stress response, but that factors other than neural stimuli and prostaglandins are important in releasing postoperative granulocytosis.

Long-term results of bladder neck incision in men.

A retrospective cohort of 163 male patients having either uni- (UI) or bilateral incision (BI) of the bladder neck to relieve infravesical obstruction was reviewed. Short-term results were excellent with significant improvement of flow rates. 82% (UI) and 87% (BI) of the incised patients were satisfied. Long-term results were assessed by a life-table analysis. 17% (UI) and 12% (BI) of the patients needed a reoperation during the observation period of 6 years. It is concluded that bladder neck incision is a method with few complications and favourable long-term results.

Mucosal function of the perfused ileum in patients with and without diarrhoea and dumping after vagotomy and pyloroplasty.

Perfusion studies of the terminal ileum were performed in patients who had previously had vagotomy and pyloroplasty performed for peptic ulcer disease and who at follow-up study had either diarrhoea or dumping, or no symptoms (the control group). The aim was to elucidate possible pathophysiological factors contributing to the sequelae. Net movements of water, electrolytes, and sugars, unidirectional fluxes of sodium and chloride, and the transmural electrical potential difference (PD) were measured simultaneously with and without the influence of chenodeoxycholic acid (CDC), 1.0 mmol/l, in the intestinal lumen. In patients without symptoms or with dumping, water and sodium chloride were absorbed during the control perfusion. Addition of CDC reduced the absorption or evoked secretion. In patients with diarrhoea the control perfusion disclosed a large spontaneous ileal secretion that was not influenced by CDC. The secretion was mainly due to a reduced mucosa-to-serosa flux of sodium and chloride and, to a lesser extent, to an increased serosa-to-mucosa flux. The diarrhoea patients showed an increased xylose absorption rate, suggesting an increased interepithelial leakiness. No change in PD was demonstrated. The effect of CDC on the unidirectional fluxes was identical in all three groups of patients. In conclusion, our findings suggest that the basic biological mechanisms are identical (and normal) in all patients, but the ileal epithelium of patients with diarrhoea secretes spontaneously and seems to be prestimulated by some at present unidentified agent.

Cimetidine as an adjuvant treatment in colorectal cancer. A double-blind, randomized pilot study.

PURPOSE: To evaluate the influence of a H2 receptor antagonist (cimetidine) on survival in patients with colorectal carcinoma, a randomized, controlled pilot study was performed in three university hospitals in Copenhagen, Denmark. METHODS: A total of 192 patients, who had undergone a resection or an exploratory operation for adenocarcinoma of the colon or rectum between May 1988 and May 1991, were enrolled in the study. After a median observation time of 40 months, outcome was noted for each patient concerning cancer-specific mortality rate. RESULTS: In patients operated with curative intent (n = 148), no difference was found in cancer-specific mortality between the two treatments. However, a tendency toward reduction in mortality rate was found in patients with curatively operated Dukes Stage C carcinoma (P = 0.11, log-rank test; difference, 29 percent; 90 percent confidence interval, 2 to 57 percent) in the cimetidine-treated group. In patients with disseminated disease no total difference was found between the two treatment groups. CONCLUSIONS: Cimetidine does not seem to reduce mortality in patients with colorectal cancer, but there seems to be a tendency toward a survival benefit in patients undergoing surgery for Dukes Stage C carcinoma. Results seem to justify trials in this patient category to reveal a benefit of H2 receptor antagonists in adjuvant therapy of colorectal carcinoma.

Complications following postoperative combined radiation and chemotherapy in adenocarcinoma of the rectum and rectosigmoid. A randomized trial that failed.

A randomized multicenter trial was started to evaluate the effect of irradiation combined with 5-fluorouracil and methotrexate on survival after surgery for rectal and rectosigmoidal carcinoma, Dukes' stages B and C. The trial was terminated prematurely after entrance of 34 patients due to frequent and serious complications. Three patients died as a direct consequence of the adjuvant treatment.