Influence of implantation on the electrochemical properties of smooth and porous TiN coatings for stimulation electrodes

OBJECTIVE

To determine whether changes in electrochemical properties of porous titanium nitride (TiN) electrodes as a function of time after implantation are different from those of smooth TiN electrodes.

APPROACH

Eight smooth and 8 porous TiN coated electrodes were implanted in 8 rats. Before implantation, voltage transients, cyclic voltammograms and impedance spectra were recorded in phosphate buffered saline (PBS). After implantation, these measurements were done weekly to investigate how smooth and porous electrodes were affected by implantation.

MAIN RESULTS

The electrode capacitance of the porous TiN electrodes decreased more than the capacitance of the smooth electrodes due to acute implantation under fast measurement conditions (such as stimulation pulses). This indicates that protein adhesion presents a greater diffusion limitation for counter-ions for the porous than for the smooth electrodes. The changes in electrochemical properties during the implanted period were similar for smooth and porous TiN electrodes, indicating that cell adhesion poses a similar diffusion limitation for smooth and porous electrodes.

SIGNIFICANCE

This knowledge can be used to optimize the porous structure of the TiN film, so that the effect of protein adhesion on the electrochemical properties is diminished. Alternatively, an additional coating could be applied on the porous TiN that would prevent or minimize protein adhesion.

Melanin-based skin spots reflect stress responsiveness in salmonid fish

Within animal populations, genetic, epigenetic and environmental factors interact to shape individual neuroendocrine and behavioural profiles, conferring variable vulnerability to stress and disease. It remains debated how alternative behavioural syndromes and stress coping styles evolve and are maintained by natural selection. Here we show that individual variation in stress responsiveness is reflected in the visual appearance of two species of teleost fish; rainbow trout (Oncorhynchus mykiss) and Atlantic salmon (Salmo salar). Salmon and trout skin vary from nearly immaculate to densely spotted, with black spots formed by eumelanin-producing chromatophores. In rainbow trout, selection for divergent hypothalamus-pituitary-interrenal responsiveness has led to a change in dermal pigmentation patterns, with low cortisol-responsive fish being consistently more spotted. In an aquaculture population of Atlantic salmon individuals with more spots showed a reduced physiological and behavioural response to stress. Taken together, these data demonstrate a heritable behavioural-physiological and morphological trait correlation that may be specific to alternative coping styles. This observation may illuminate the evolution of contrasting coping styles and behavioural syndromes, as occurrence of phenotypes in different environments and their response to selective pressures can be precisely and easily recorded.

Depression assessed over 1-year survival in patients with myocardial infarction

OBJECTIVE

To estimate the prevalence of ICD-10 depression using a self-reported questionnaire and to examine if depression is associated with increased 1-year mortality in patients with myocardial infarction (MI).

METHOD

In total, 763 MI-patients completed the Major Depression Inventory at discharge. Information from hospital notes was collected and patients were followed 1 year for re-admission and mortality through national registries.

RESULTS

Seventy-three patients (9.6%) were depressed at discharge. Depression was not a significant independent predictor of mortality; however, there was a significant trend for increasing mortality with increasing severity of the depressive state (P = 0.028). All mortality among depressed patients was in patients with non-Q-wave infarction.

CONCLUSION

Ten per cent of MI-patients fulfilled diagnostic criteria for depression at discharge. There was a significant trend for increasing mortality with increasing severity of the depressive episode. All mortality among depressed patients was seen in patients with non-Q-wave infarction. These findings indicate future studies in selected subgroups of MI-patients.

Psychosocial predictors of depression in patients with acute coronary syndrome

OBJECTIVE

To describe the prevalence of depression according to ICD-10 criteria using a self-completed questionnaire and to identify psychosocial predictors of depression at discharge in patients with acute coronary syndrome.

METHOD

A total of 899 patients with acute coronary syndrome completed the Major Depression Inventory at discharge and a questionnaire regarding previous depression and family history of depression. Information concerning civil status was obtained from the Civil Person Registry.

RESULTS

Ninety patients (10%) were depressed according to ICD-10 criteria at discharge with 7.2% having a moderate to severe depression at discharge. Women were significantly more frequently and severely depressed than men. Patients with and without depression reported primarily somatic symptoms of depression. Cardiovascular risk factors or treatment did not differ between patients with and without depression. Previous depression (OR 2.9, 95% CI 1.4-6.0 adjusted) and female gender (OR 2.5, 95% CI 1.5-4.3 adjusted) predicted depression at discharge in a logistic regression model.

CONCLUSION

Somatic symptoms of depression are prevalent in patients with acute coronary syndrome. The use of self-completed non-diagnostic questionnaires assessing symptoms of depression therefore is cautioned as patients may wrongly be identified as depressed. In patients with acute coronary syndrome depression is predicted by well-known psychosocial risk factors.

EEG-Monitored ECT: A Comparison of Seizure Duration under Anesthesia with Etomidate and Thiopentone

Electroencephalogram-monitored electroconvulsive therapy (ECT) was carried out in 20 depressed inpatients. Before treatment, patients were randomly allocated to treatment using etomidate (Hypnomidat) (n = 10) or thiopentone (n = 10) for anesthesia. The groups were matched for sex, age, weight, and type and severity of depression. The seizure duration (seconds) was measured by electroencephalography (EEG), and the electrical energy (Joules, J) was determined for each treatment. A ratio of seizure duration:electrical energy (s/J) was computed. Both seizure duration and seizure duration:electrical energy were greater in the etomidate group than in the thiopentone group, whereas electrical energy did not differ significantly. The number of treatments in the etomidate group did not differ from that in the thiopentone group, as may be expected, perhaps because of the small size.

Ranitidine reduces postoperative interleukin-6 induced C-reactive protein synthesis

BACKGROUND

The mechanism of post-traumatic immunosuppression is still not known in detail. However, histamine released during trauma and major surgery may play a significant role in the process. Previously, we showed that the histamine-2 receptor antagonist (H2RA), ranitidine, reduced trauma-induced suppression of certain immunological parameters.

STUDY DESIGN

The effect of perioperative ranitidine on postoperative change in plasma interleukin-6 (IL-6) and serum C-reactive protein (CRP) levels was assessed in 23 women undergoing elective abdominal hysterectomy. The patients were randomized to receive intravenous ranitidine, 100 mg twice a day from skin incision, for two days, followed by oral ranitidine, 150 mg twice a day, for a further three days, or no ranitidine. Interleukin-6 and CRP were analyzed in plasma and serum, respectively, drawn preoperatively and six, 24, 48, and 120 hours after skin incision.

RESULTS

Routine blood analyses, clinical data (except age), duration of surgery, anesthesia, antibiotic prophylaxis, blood loss, and perioperative blood transfusion were similar in the two groups. Interleukin-6 levels were significantly increased in all patients and without difference between the ranitidine-treated and non-ranitidine-treated patients after six, 24, and 48 hours compared to preoperative levels, respectively. C-reactive protein levels were also significantly increased in all patients after 24, 48, and 120 hours, respectively; however, at 48 hours, CRP was significantly reduced in ranitidine-treated patients compared with non-ranitidine-treated patients (p = 0.02).

CONCLUSIONS

These results suggest that histamine-2 receptor activation mechanisms may not be involved in postoperative IL-6 synthesis. However, the reduced CRP level in ranitidine-treated patients suggests that H2RAs modulate IL-6 signal transduction in hepatic cells.

[Inguinal funicular block in vasectomy]

The analgesic efficacy of inguinal funicular block with 10 ml carbocaine 1% as a supplement to local infiltration analgesia of the vas deferens was investigated in patients undergoing vasectomy. Pain/discomfort during vasectomy and on the first and third day postoperatively were investigated using a questionnaire. Fifty-seven male patients scheduled for legal sterilization were randomized and allocated in a double-blinded manner to receive the 10 ml carbocaine 1% in the right or left side and 10 ml isotonic NaCl in the contralateral side, the patient then being his own control. There was significantly less intraoperative pain on the side of the active inguinal funicular block (p < 0.0001), but no significant differences were found at the first and third postoperative day (p = 1.16-1.19). Inguinal funicular block can be recommended as a supplement to the usual use of local infiltration analgesia of the vas deferens.

[Buprenorphine for postoperative analgesia after total hip alloplasty]

Three different post-operative pain relief schedules were investigated in a double blind study after total hip replacement. Group BS received a priming dose of buprenorphine i.m. at the time of wound closure and continued with sublingual buprenorphine every eight hours. Supplementary doses of buprenorphine i.m. could be demanded. Group B and M received a priming dose of buprenorphine and morphine respectively, and continued with sublingual placebo eight hourly. Supplementary doses of buprenorphine could be demanded by patients in Group B and supplementary doses of morphine by patients in Group M. On one occasion VAS scorings of groups BS and B were statistically significantly lower than group M, and on another occasion VAS scorings of group BS were statistically significantly lower than the other two groups. Furthermore, the number of on demand supplementary doses was statistically significantly higher in group M. It is concluded that buprenorphine administered at regular intervals as well as on demand provided better postoperative analgesia than morphine at present dose levels. In this context, only moderate advantages were obtained by administering buprenorphine at regular intervals.

Surgical treatment of large pericardial effusions. Etiology and long-term survival

From 1977 to 1988 60 patients were treated for large pericardial effusion. The operation consisted of a small left anterior thoracotomy with formation of a pericardial window. In 28 patients (47%) the etiology was a malignant disease. Eight patients (29%) had malignant cells in the pericardial fluid and 23 patients (82%) had metastases to the pericardium. Seven patients (12%) had purulent pericarditis; in 4 cases Staphylococcus was found. Of the remaining 25 patients, the etiology remained unknown in 13. The 5-year survival rate was 60% among patients with nonmalignant effusions. In patients with malignant effusions only 20% were alive after 2 years. There were no deaths related to the operation. We conclude that large pericardial effusions of unknown etiology can be safely treated with a small left anterior thoracotomy. This access gives optimal possibilities for rapid diagnosis and treatment.

Psychotropic medication in the elderly. A survey of prescribing and clinical outcome

Due to the increasing elderly population, an increased number of elderly patients requires treatment for mental and behavioural disorders. There are relatively few clinical studies of the prescribing of psychotropic drugs in patients over 65 years of age. A prospective study was undertaken at three centres caring for the elderly, encompassing patients from general nursing homes and a psychiatric department. Entry of patients into the survey was determined by the clinical decision to prescribe psychotropic medication and an age of 65 years or older. Included in the study were 160 patients. The main reasons for initiating psychotropic medication were indicated, and anamnestic data were collected. Initial and continuing dosages of psychotropic medication were recorded. The clinical condition was assessed at the start of treatment and after four and eight weeks, utilising the Clinical Global Impressions (CGI) scale. The patient's daily activity using an abbreviated Stockton Geriatric Rating Scale (SGRS) was assessed. Side effects were recorded using the UKU Scale. Clinical improvement was seen in about half of the patients with the best effect in patients with mainly psychotic symptoms. Patients with chronic dementia-related problems responded less well. Side effects were few and generally mild. This situation may relate to cautious introduction of the medication and adoption of low-dose regimens. All centres avoided, if possible, psychotropic polypharmacy.

Effect of major surgery on absorption rate of NPH insulin injected s.c

The absorption rate of NPH insulin injected s.c. was evaluated before operation and on the day of surgery by continuous measurements of residual radioactivity of 125I-labelled insulin in 10 patients undergoing major abdominal surgery. The results show that major surgery has no effect on rate of absorption of intermediate acting insulin.

[The occurrence of late thromboembolic complications after elective abdominal surgery]

Forty-five consecutive patients who were submitted to elective major abdominal surgical interventions under optimal thromboembolic prophylaxis participated in an investigation as regards the occurrence of late thromboembolic complications. The patients were followed postoperatively with 125I-fibrinogen scanning every second day for a week or until discharge from hospital. If deep venous thrombosis was suspected, intravenous phlebography was carried out. Thirty-five patients completed the investigation. None of the patients developed deep venous thrombosis during thromboembolic prophylactic treatment. In two patients (6%) (95% confidence limits 1-19%), deep venous thrombosis was demonstrated after conclusion of prophylaxis, 13 and 28 days postoperatively, respectively. It is concluded that despite optimal thrombosis prophylaxis, late thromboembolic complications may occur. Prospective investigations are required to elucidate the clinical significance of late thromboembolic complications and to illustrate the value of prolonged thrombosis prophylaxis.

Antibiotic prophylaxis in surgery for hip fractures

Totally, 185 patients, operated on for a fresh hip fracture, were randomly allocated to either methicillin antibiotic prophylaxis or no prophylaxis and followed for 1 month. Two superficial wound infections were recorded in the prophylaxis group and one in the control group. Prophylactic use of antibiotics in surgery for hip fractures seems unnecessary provided strict aseptic routines in the operating room are followed.

[Cecostomy can not be recommended as a routine method in the treatment of acute left-sided obstructive colon cancer]

During a period of 17 years, 135 patients with acute left-sided obstructive cancer of the colon were admitted to two hospitals in the County of Copenhagen. Primary decompression by means of coecostomy was performed. The plan was to perform resection of the tumour after some weeks and colocolic anastomosis and closure of the coecostomy either spontaneously or operatively after some months. The total mortality was 24%. A total of 84 patients (62%) completed the planned therapeutic course, 21 without complications. Eighteen patients survived with permanent coecostomies. The mortality in this material was similar to those in materials where other therapeutic regimes were employed. The prolonged therapeutic programme and considerable morbidity thus do not result in reduction in the mortality. The authors cannot therefore recommend primary decompressive coecostomy. This method can only be recommended as an emergency measure under local anaesthesia for patients in such poor general condition that other forms of treatment are not possible.

Hydrocele in children: indication for operation and surgical technique

Hydroceles in children less than one year old should only be treated surgically when discomfort occur, as spontaneous remission is to be expected in this age group. Surgery is nearly always indicated in older children. In a consecutive series of 83 children operated for hydrocele, a follow-up study found a 2% recurrence rate, after an average of 5 years observation, despite the ligation of the processus vaginalis at the anulus inguinalis profundus. In that only 7% of the children developed a contralateral hydrocele, routine exploration on this side is deemed unnecessary.

[Sclerotic and atrophic lichen of the genitals in boys]

Sclerotic and atrophic lichen (LSA) is a rare condition in boys. A retrospective analysis of boys who underwent circumcision for medical reasons, revealed that nine out of 59 boys had histologically verified LSA. The condition thus appears to be a relatively frequent cause of phimosis in children.

The influence of age upon the survival after curative operation for colorectal cancer

From 1962 to 1982 1,623 consecutive patients were curatively operated for colorectal adenocarcinoma. For all patients cancer specific mortality rates were registered and the influence of the following prognostic factors was evaluated: tumour stage and grade, adenomas, age, sex and tumour site. In a multivariate Cox analysis, with backward elimination of non-significant factors at a 10% level, Dukes' C stage, poor differentiation, and age between 40 and 60 years at onset of carcinoma reached independent prognostic significance.

Intraincisional antibiotic in addition to systemic antibiotic treatment fails to reduce wound infection rates in contaminated abdominal surgery. A controlled clinical trial

One hundred ninety patients with peritonitis at the time of abdominal surgery were allocated at random to systemic antibiotic treatment alone or systemic antibiotic treatment combined with topical application of antibiotics in the wound at the time of wound closure. The overall wound infection rate was 17 percent without significant difference between the two treatment groups (P greater than 0.80).

Appendicitis and enterobiasis in children

The importance of Enterobius vermicularis in the pathogenesis of appendicitis is not known. The authors found Enterobius in 38 (12.5%) of 303 appendices removed from children. No evidence was obtained for a pathogenic effect of the parasite in appendicitis: Negative laparotomy was significantly more common in the infested group than in the other children. The findings support the theory that E. vermicularis can cause symptoms resembling true appendicitis viz. appendicopathia oxyurica.

Linear incision and curettage vs. deroofing and drainage in subcutaneous abscess. A randomized clinical trial

Linear incision plus curettage under antibiotic cover was compared with conventional deroofing and drainage of subcutaneous abscess in a randomized study of 50 patients. The median healing time was 9 days following linear incision and curettage and 15 days after deroofing and drainage (p less than 0.05). There was no recurrence of abscess during follow-up for 6 months. Linear incision plus curettage under single-dose antibiotic cover thus proved to be a safe method with significantly shorter healing time than after conventional deroofing an drainage.

Infravesical obstruction caused by a retrovesical malignant schwannoma

A 77-year-old male presented himself with acute urinary retention, and a history of infravesical obstruction. Cystourethroscopy failed to show the obstruction. A malignant schwannoma (MS) causing impression in the bladder was removed through a laparotomy. Postoperatively there were no urologic symptoms, and the urodynamic investigations had changed to normal.

A long-term gastrointestinal follow-up in patients operated on for congenital hypertrophic pyloric stenosis

A gastrointestinal follow-up of 91 patients operated on for congenital hypertrophic pyloric stenosis (CHPS) between 1942 and 1964, using the Fredet-Ramstedt method, is presented. Among 85 patients available for follow-up, 72 responded to a request for reexamination. These patients were interviewed personally by one of the authors. Thirty-four patients (47%) consented to have a Roentgen examination done, performed as a double contrast study, investigating the structure and function of the stomach and duodenum. Forty-two patients (58%) had varying minor gastrointestinal complaints. Only two patients had severe symptoms. X-ray examination in 34 patients (47%) showed only three with pathological changes, i.e. one with mild deformation of the duodenal bulb, another with slight duodenal reflux. The third X-ray showed massive gastric retention with duodenal bulb deformation. The patient suffered from severe dyspepsia and vomitus. No correlation was found between the severity of the CHPS and the presence of later gastrointestinal symptoms. It is concluded that the Fredet-Ramstedt's operation for CHPS is an efficious operation with few perioperative complications and good long-term results.

Influence of diabetes mellitus on operative risk

In a retrospective study postoperative morbidity was compared between 224 patients with diabetes mellitus and 224 non-diabetic control patients matched with regard to operative procedure (major vascular, abdominal and acute surgery for hip fracture), sex, age, complicating cardiovascular disease and weight. Forty-six patients in each group had complications, without any trend towards specific morbidity in the diabetic group. Incidence of morbidity was similar in diabetic patients treated with insulin, oral antidiabetic agents or diet. Diabetic patients with complications had significantly (P less than 0.01) lower blood glucose pre- and postoperatively than those without complications. The risk of overlooking (type II error) a 25 per cent increase in complication rate in the diabetic patients was less than 10 per cent and the risk of overlooking a 50 per cent increase in morbidity less than 0.5 per cent. These results do not support the common belief that diabetes per se may increase surgical risk.

Morbidity after femoral neck fracture not increased in diabetics

In a retrospective study the morbidity following surgery for femoral neck fracture was investigated in 81 patients with diabetes mellitus and in 81 non-diabetic matched control patients. Sixteen patients in each group had postoperative complications with no tendency to specific complications in the diabetic patients. Morbidity was equally distributed between patients treated with insulin, antidiabetic agents, and diet. Our results do not support the common belief that there is an increased postoperative risk in diabetic patients.

Strictures of the male urethra treated by the Otis method

During a 5-year interval 72 consecutive patients with urethral strictures were treated by internal urethrotomy according to the method of Otis. The etiology, surgical technique, complications and postoperative management are discussed. The results after a mean followup of 29 months showed an over-all success rate of 82 per cent (95 per cent confidence limits 71 to 90 per cent). It is concluded that internal urethrotomy should be considered for primary treatment of urethral strictures, since the procedure is easy and complications are few.