Pain management in ambulatory surgery.

Successful ambulatory surgery is dependent on analgesia that is effective, has minimal adverse effects, and can be safely managed by the patient at home after discharge. A number of studies have identified that the provision of effective postoperative analgesia is inadequate for a significant proportion of patients. The following discussion details the current available analgesic options for ambulatory surgery patients and the rationale for their use. Preemptive analgesia should be given to all patients unless there are specific contraindications. Consideration should be given to the use of long-acting oral COX-2 selective nonsteroidal anti-inflammatory drugs (NSAIDs) and long-acting oral opioids to treat postoperative pain. A standardized multimodal postdischarge analgesic regimen tailored to the patient's expected postoperative pain levels should be prescribed. Patient follow-up by telephone questionnaire will confirm those surgical procedures that result in mild or moderate-to-severe postoperative pain and the effectiveness of treatment plans.     

Bicarbon valve - European multicenter clinical evaluation

Objective: Fifteen collaborating centers in eight countries present their pooled experience with the new Bicarbon™ bileaflet valve. Methods: Between 4/90 and 4/96, 1351 patients, 806 males and 545 females, aged 10 to 83, mean 58.4±12.4, underwent valve implantation. Operations: AVR, 726; MVR, 475; DVR, 150. Additional procedures: CABG, 211; TV repair, 64; other, 152. Results: Mortality: 67 early (seven valve related) and 56 late (40 valve related). Valve thrombosis: six obstructive, three non-obstructive; embolism: nine major cerebral, 37 other. Major bleeding: 29. Hemolysis: two clinically significant. Non-structural dysfunction: 24 paravalvular leaks, one leaflet interference. No structural failure! Endocarditis: 24. Reoperation 48: 22 non-structural dysfunctions, 14 endocarditis, seven thrombosis and embolism, five other. Estimated 5-year freedom from valve-related deaths is 97.2% for AVR and 92.4% for MVR; 4-year freedom from valve related deaths for DVR is 90.5%. Mean calculated NYHA improvement is 1.24. Conclusions: The Bicarbon mechanical prosthesis is well designed, durable, has good hemodynamic features and an acceptably low incidence of complications.     

The effects of paracetamol (acetaminophen) on hepatic tests in patients who chronically abuse alcohol – a randomized study

Aliment Pharmacol Ther 2010; 32: 478–486

Summary

Background Retrospective accounts suggest that therapeutic doses of paracetamol can produce severe hepatic injury in patients with putative high‐risk conditions, including alcoholism and infectious hepatitis. Metabolism of paracetamol to its hepatotoxic metabolite is enhanced in patients who abuse alcohol, who also have compromised liver defences from depressed hepatic glutathione. Aim To determine the effect of paracetamol on serum liver tests of newly abstinent subjects who abuse alcohol, including subjects with hepatitis C infection. Methods A randomized, double‐blind, placebo‐controlled study. Adult alcohol abusers with a current drinking episode longer than 7 days received either placebo or paracetamol 4 g/day for 5 days. Results Of 142 subjects enrolled, 74 received paracetamol and 68 received placebo. Mean ALT activity during treatment increased from 48 to 62 IU/L in the paracetamol group and from 47 to 49 IU/L in the placebo group. Maximum ALT was 238 and 249 IU/L in the paracetamol and control groups respectively. The INR remained unchanged and serum bilirubin decreased in both groups. Subgroup analyses for subjects with alcoholic hepatitis, hepatitis C virus antibody and other subgroups showed no statistical difference between groups. Conclusion Administration of paracetamol 4 g/day appears safe in newly abstinent patients who abuse alcohol.     

Importance of plasmapheresis in the treatment of paraneoplastic cerebellar degeneration

Paraneoplastic neurologic syndromes are disorders of the nervous system function caused by cancer but not due to metastatic disease, vascular or metabolic deficits, infections, nutritive deficiency, nor side effects of antineoplastic drugs or irradiation. Immunologic factors probably play the crucial role in the pathogenesis of paraneoplastic neurologic syndromes, but nonimmunologic mechanisms that include metabolic abnormalities and competition for substrate are also involved. Paraneoplastic cerebellar degeneration most commonly occurs in the setting of gynecologic cancers, but it accompanies the small-cell lung cancer too. Other tumors are infrequently associated with cerebellar degeneration. Several paraneoplastic antibodies have been identified in patients with paraneoplastic cerebellar degeneration. Their association with particular cancers may help identify an occult lesion. Anti-Yo antibodies are directed against Purkinje cell antigens and occur in patients with cerebellar degeneration who have breast cancer or gynecologic tumors. A target antigen of anti-Yo antibody is CDR2 protein that is normally expressed only in the brain and testis. Patients with paraneoplastic cerebellar degeneration present with dizziness, nausea and vomiting followed by gait instability, diplopia, gait and appendicular ataxia, dysarthria and dysphagia. Therapeutic options include tumor excision, chemotherapy and/or irradiation, and adjuvant therapy with glucocorticoids, immunoglobulins and plasmapheresis. The role of plasmapheresis in the treatment of paraneoplastic cerebellar degeneration is still uncertain. Reports of its efficacy are anecdotal. We present patient with paraneoplastic cerebellar degeneration with positive anti-Yo antibodies and tumor of the ovaries whose neurologic status significantly improved after four daily plasmaphereses, which was accompanied by a fourfold decrease in the anti-Yo antibodies titer. Further investigations are needed to define a protocol for plasmapheresis in the treatment of patients with paraneoplastic syndromes.     

Expression of retinoblastoma protein in human growth hormone-secreting pituitary adenomas

The retinoblastoma gene (RB1) is a tumor-suppressor gene in chromosomal region 13q14.2. Its role in the pathogenesis of pituitary tumors has not been fully clarified. Some studies have shown that losses in this chromosomal region are related to aggressive tumor behavior, although the retinoblastoma protein (pRB) is still expressed. Conversely, lack of expression of pRB was observed in one fourth of GH-secreting pituitary adenomas (GH-tumors). In order to further study the expression of pRB in GH-tumors, we evaluated this protein in 49 tumors from patients with acromegaly (20 noninvasive, 25 invasive, and 4 with no information) and 8 normal pituitaries using immunohistochemistry (IHC). Nuclear staining for pRB ranged from 0 to 90% (median 40%) in the tumors and from 40 to 80% (median 58%) in normal pituitaries. In 10 tumors (20% of total) the adenomatous cells were negative (5 cases) or had very low labeling (5 cases) for pRB. Sixty three percent (31/49) of the tumors showed staining in 10–80% of the cells and in 16% (8/49) of the cases >80% of the adenomatous cells were positive for pRB. The expression of pRB was not different in invasive and noninvasive tumors. In conclusion, pRB is underexpressed in a subgroup of GH-tumors, and this may represent an early event in the pathogenesis of this tumor subtype.     

Amiloride enhances the secretion but not the synthesis of renin in renal juxtaglomerular cells

In this study we have examined a potential role of the sodium/proton exchange system in the regulation of renin secretion. We found that the inhibitors of the Na⁺/H⁺ antiport, amiloride (1 mM) and ethylisopro-pylamiloride (EIPA, 50 M), led to a 125% increase of renin secretion from cultured mouse juxtaglomerular cells. The stimulatory effect of EIPA on renin secretion was dependent on the extracellular concentrations of sodium and hydrogen ions. While lowering the extracellular pH from 7.3 to 7.0, and lowering [Na⁺]_e from 130 mM to 5 mM had no effect on basal renin release, it markedly attenuated or even blunted the effect of EIPA on renin secretion. The stimulatory effect of forskolin on renin secretion, however, was not altered by decreases of extracellular pH and of sodium. Inhibition of basal renin release was achieved with angiotensin II (1 M). In the presence of EIPA the inhibitory effect angiotensin II was markedly attenuated. Although effective on renin secretion, neither amiloride nor EIPA exerted a significant effect on the de novo synthesis of renin in cultured mouse JG cells. These findings are compatible with the idea that an amiloride-sensitive transport process, presumably the Na⁺/H⁺ exchanger, acts indirectly as an inhibitory signal transduction system for renin secretion from renal juxtaglomerular cells.