Quality of life and functional outcomes 10 years after laparoscopic radical prostatectomy

Background. Minimally invasive laparoscopic radical prostatectomy (LRP) has proven equally effective as open surgery in terms of cancer control and peroperative complication rate with less bleeding and postoperative pain. However, long-term follow-up data after LRP are scarce, especially as related to quality of life (QoL).

Aim. To compare QoL and functional outcomes at least 10 years after LRP with a population-based control group matched for age and region.

Methods. Follow-up data were obtained by mailed questionnaires from patients who responded anonymously to five international questionnaires (EQ-5D, QLQ-C30, QLQ-PR25, IPSS, and IIEF). We collected self-reported outcome data directly from 49 patients who underwent LRP more than 10 years ago in our centre. The results of the patients' overall QoL and urinary continence rates were compared with 918 controls matched for region and age.

Results. Forty-two patients (86%) and 808 (88%) controls reported having no urinary leakage. Only 11 patients (24%) still had sexual activities 10 years after LRP, and three were without erectile dysfunction. There was no difference in four of five statements of the self-assessed QoL questionnaires between the LRP and control group. Anxiety level was higher in the LRP group (44%) than in the control group (23%).

Conclusion. Patients reported high self-assessed QoL, although they also reported low sexual activity 10 years after LRP. Prevalence of urinary leakage was similar in both groups. However, anxiety was more common in LRP patients.     

Aspirin resistance in patients with type II diabetes mellitus

Background. Diabetic patients exhibit platelet hyperreactivity, which renders them resistant to antithrombotic treatments. We aimed to investigate the prevalence and predictors of aspirin resistance in diabetic patients.

Material and methods. A total of 93 diabetic and 37 non-diabetic participants were included into the study. Aspirin resistance was measured with a whole-blood desktop platelet function analyzer (PFA-100) with an epinephrine agonist.

Results. Altogether 41.9% patients with DM were aspirin non-responders. Aspirin resistance was observed in 43.2% of non-diabetic patients (p = 0.89). Presence of diabetes mellitus had no effect on aspirin response (RR 0.95 (95% CI 0.44–2.05), p = 0.89) in the whole study population. Hypercholesterolemia was the only predictor of aspirin resistance in multivariate analysis in diabetic patients (RR 3.09 (95% CI 1.17–8.16), p = 0.023).

Conclusion. The prevalence of aspirin resistance is comparable in diabetic and non-diabetic patients. Hypercholesterolemia is the only independent predictor of aspirin resistance in diabetic patients.     

Predicting return to work among sickness-certified patients in general practice: Properties of two assessment tools

Aim. The purpose was to analyse the properties of two models for the assessment of return to work after sickness certification, a manual one based on clinical judgement including non-measurable information (‘gut feeling’), and a computer-based one.

Study population. All subjects aged 18 to 63 years, sickness-certified at a primary health care centre in Sweden during 8 months (n = 943), and followed up for 3 years.

Methods. Baseline information included age, sex, occupational status, sickness certification diagnosis, full-time or part-time current sick-leave, and sick-leave days during the past year. Follow-up information included first and last day of each occurring sick spell. In the manual model all subjects were classified, based on baseline information and gut feeling, into a high-risk (n = 447) or a low-risk group (n = 496) regarding not returning to work when the present certificate expired. It was evaluated with a Cox’s analysis, including time and return to work as dependent variables and risk group assignment as the independent variable, while in the computer-based model the baseline variables were entered as independent variables.

Results. Concordance between actual return to work and return to work predicted by the analysis model was 73%–76% during the first 28–180 days in the manual model, and approximately 10% units higher in the computer-based model. Based on the latter, three nomograms were constructed providing detailed information on the probability of return to work.

Conclusion. The computer-based model had a higher precision and gave more detailed information than the manual model.     

Patients’ experience of outsourcing and care related to magnetic resonance examinations

Background. Outsourcing radiological examinations from public university hospitals affects the patient, who has to attend a different clinic or hospital for the radiological examination. We currently have a limited understanding of how patients view outsourcing and their care related to MR examinations.

Aim. To examine the experiences of patients who are sent to private radiology units when their referrals for MR examinations are outsourced from a university hospital, as well as to explore factors which influence patient satisfaction regarding the quality of care related to the MR examination.

Methods. A group of patients (n = 160) referred for MR examinations and either examined at a university hospital or at an external private unit were interviewed. The interview was designed as a verbal questionnaire. Data were analyzed using Student’s t test, analysis of variance (ANOVA), and Pearson’s correlation.

Results. Sixty-nine percent of the patients could neither choose nor influence the location at which they were examined. For those who could, aspects that influenced the patient’s choice of radiology department were: short waiting time 79% (127/160), ease of traveling to the radiology department 68% (110/160), and short distance to their home or work 58% (93/160). For 40% (60/160) of the patients, a short time in the waiting room was related to a positive experience of the MR examination.

Conclusion. If patients were informed about outsourcing and could also choose where to have their examination, key factors contributing to patient satisfaction could be met even when MR examinations are outsourced.     

Combination treatment with an erythropoiesis-stimulating agent and intravenous iron alleviates anaemia in patients with hereditary haemorrhagic telangiectasia

Background. Patients with hereditary haemorrhagic telangiectasia (HHT) suffer from recurrent epistaxis and bleeding from gastrointestinal telangiectasias that occur despite otherwise normal haemostasis and result in iron deficiency anaemia with increasing severity. In advanced disease, anaemia may be severe, be irresponsive to iron supplementation, and may lead to red blood cell transfusion dependency.

Methods. We conducted a retrospective study at our Centre for Osler’s Disease to evaluate the effectiveness of adding an erythropoiesis-stimulating agent (ESA) to intravenous iron supplementation in the management of anaemic HHT patients. Blood values and treatment parameters were collected for nine months before combination therapy (iron supplementation only) and 12 months during combination therapy (iron supplementation plus ESA).

Results. Four patients received intravenous iron and an ESA with mean weekly doses of 126 mg and 17,300 units (U), respectively. Mean haemoglobin improved significantly during combination therapy, from 106 g/L to 119 g/L (p < 0.001).

Conclusion. Anaemia can be alleviated in patients with HHT who are irresponsive to intravenous iron supplementation, by addition of an ESA. The proposed mechanism behind the iron irresponsiveness is that the anaemia is caused by a combination of recurrent haemorrhage and anaemia of chronic disease.     

Association between perioperative blood transfusion and early postoperative cognitive dysfunction in aged patients following total hip replacement surgery

Introduction. Accumulating evidence suggests that enhanced inflammatory responses contribute to the pathogenesis of postoperative cognitive dysfunction (POCD). Blood transfusion can trigger an enhancement of acute inflammatory responses. Therefore, we hypothesized that perioperative blood transfusion is associated with a higher risk of POCD in aged patients following total hip replacement surgery.

Material and methods. Patients older than 65 years undergoing elective total hip replacement surgery were enrolled from October 2011 to December 2012. Neurocognitive tests were evaluated at baseline and at 7 d after surgery by a Mini-Mental State Test. Multivariate logistic regression analysis was used to determine risk factors associated with POCD.

Results. Fifty-six patients (27.3%) developed POCD 7 d postoperatively. Patients who developed POCD were older, had a lower education level and preoperative hemoglobin concentration, had more blood loss, and had a lower body weight (p < 0.05). Patients with POCD were more likely to receive red blood cells (RBCs) transfusion (51.8% versus 31.5%; p < 0.05). A multivariable logistic regression model identified older age, lower education level, and perioperative blood transfusion of more than 3 units as independent risk factors for POCD 7 d postoperatively.

Conclusion. Our data suggested that perioperative blood transfusion of more than 3 units of RBCs is an independent risk factor for POCD in aged patients following total hip replacement surgery.     

Escalated handling of young C57BL/6 mice results in altered Morris water maze performance

Background. The handling of experimental animals prior to experimental interventions is often poorly described, even though it may affect the final functional outcome. This study explores how the use of repeated handling of C57BL/6 mice prior to Morris water maze (MWM) tests can affect the performance.

Methods and materials. The handled animals were subjected to the escalating handling protocol, with the investigator spending 5 min per day per cage for 8 days prior to the MWM test. On the last days of handling, the mice were introduced to water and the concept of a hidden platform. The MWM test consisted of four daily trials for 90 s per day for 4 days with a hidden platform. A probe test was performed 4 days after the last learning trial. Control animals were not handled prior to MWM.

Results. Handling reduced the latency to find the platform on the first 2 days of the MWM tests and reduced thigmotaxis. The mice increased their swim speed and elicited more explorative behavior in the learning trials and to some lesser extent in the probe trials.

Conclusions. The improvement in MWM navigation was most likely due to reduced stress and anxiety regarding the investigator and the test. Handled mice displayed less variability than non-handled mice, suggesting that by using a controlled handling protocol prior to the experiments fewer C57BL/6 mice would be needed to achieve statistically significant differences in studies of learning and spatial memory using MWM.     

Poly(ADP-ribose) polymerase inhibition improves endothelin-1-induced endothelial dysfunction in rat thoracic aorta

Aim. The aim of this study was to investigate whether poly(ADP-ribose) polymerase (PARP) inhibition improves endothelin-1 (ET-1)-induced endothelial dysfunction (ED).

Methods. Isolated rat thoracic aorta rings were incubated with ET-1 (10 nmol/L) in the presence or absence of either polyethylene glycol–superoxide dismutase (PEG-SOD; a cell-permeable superoxide radical scavenger, 41 U/mL) plus apocynin (a NADPH oxidase inhibitor, 300 µmol/L) or PJ34 (an inhibitor of polyADP-ribose polymerase, 3 µmol/L) for 18 h. Isometric tension studies were performed in response to acetylcholine (ACh; an endothelium-dependent vasodilator), sodium nitroprusside (SNP; an endothelium-independent vasodilator), and phenylephrine (Phe). PARP-1 and PAR (an end-product of PARP activity) expressions were evaluated by both Western blot and immunohistochemistry.

Results. Incubation of thoracic aorta rings with ET-1 resulted in a significant inhibition of the response to ACh, while SNP-induced relaxation was unaffected. The contractile response to Phe increased in arteries that were incubated with ET-1. PARP-1 and PAR expressions increased after ET-1 incubation. The diminished vasoreactivity as well as changes in expressions of PARP-1 and PAR in ET-1-incubated vessels were improved by both PEG-SOD plus apocynin and PJ34.

Conclusion. Our studies demonstrate that ED induced by ET-1 seems to be effected via oxidative stress in the thoracic aorta endothelium with subsequent activation of the PARP pathway.     

Bcl-2 maintains the mitochondrial membrane potential,but fails to affect production of reactive oxygen species and endoplasmic reticulum stress,in sodium palmitate-induced β-cell death

Background. Sodium palmitate causes apoptosis of β-cells, and the anti-apoptotic protein Bcl-2 has been shown to counteract this event. However, the exact mechanisms that underlie palmitate-induced pancreatic β-cell apoptosis and through which pathway Bcl-2 executes the protective effect are still unclear.

Methods. A stable Bcl-2-overexpressing RINm5F cell clone (BMG) and its negative control (B45) were exposed to palmitate for up to 8 h, and cell viability, mitochondrial membrane potential (Δψm), reactive oxygen species (ROS) generation, endoplasmic reticulum (ER) stress, and NF-κB activation were studied in time course experiments.

Results. Palmitate exposure for 8 h resulted in increased cell death rates, and this event was partially counteracted by Bcl-2. Bcl-2 overexpression promoted in parallel also a delayed induction of GADD153/CHOP and a weaker phosphorylation of BimEL in palmitate-exposed cells. At earlier time points (2–4 h) palmitate exposure resulted in increased generation of ROS, a decrease in mitochondrial membrane potential (Δψm), and a modest increase in the phosphorylation of eIF2α and IRE1α. BMG cells produced similar amounts of ROS and displayed the same eIF2α and IRE1α phosphorylation rates as B45 cells. However, the palmitate-induced dissipation of Δψm was partially counteracted by Bcl-2. In addition, basal NF-κB activity was increased in BMG cells.

Conclusions. Our results indicate that Bcl-2 counteracts palmitate-induced β-cell death by maintaining mitochondrial membrane integrity and augmenting NF-κB activity, but not by affecting ROS production and ER stress.     

An uncommon cause of acutely altered mental status in a renal transplant recipient

Introduction. Neurological complications are quite frequent in patients after solid organ transplantation presenting with focal or generalized neurologic symptoms as well as altered mental status. Posterior reversible encephalopathy syndrome is a rare cliniconeuroradiological entity characterized by headache, altered mental status, cortical blindness, seizures, and other focal neurological signs and a diagnostic magnetic resonance imaging.

Case report. We present a case of a 57-year-old woman with one episode of seizures and sudden onset of altered mental status (time and person perception) accompanied with headache at the thirtieth postoperative day after renal transplantation.

Conclusion. Posterior reversible encephalopathy syndrome, although an uncommon post-renal transplantation complication, should be considered in these patients, as several factors surrounding the setting of transplantation have been implicated in its development. Thus, physicians should be aware of this condition in order to establish the diagnosis and offer appropriate treatment.     

Effects of cyclooxygenase inhibition on insulin release and pancreatic islet blood flow in rats

Objectives. To examine the effects of inhibition of cyclooxygenase (COX) on islet hormone secretion in vitro and on pancreatic islet blood flow in vivo.

Methods. Insulin release was measured in a static incubation system of islets isolated from Wistar-F rats after inhibition of COX-1 and COX-2 with SC 560 (COX-1), FR 122047 (COX-1), rofecoxib (COX-2), or indomethacin (both COX-1 and COX-2). In other rats organ blood flow values were measured with a microsphere technique during both normo- and hyperglycemia after administration of these enzyme inhibitors.

Results. Serum insulin values were lower after pretreatment with a COX-1 inhibitor or a non-selective COX inhibitor in both control and glucose-injected rats in vivo, whereas COX-2 inhibition had no such effects. However, inhibition of COX had only minor effects on insulin release in vitro. Inhibition of COX affected neither total pancreatic nor islet blood flow in normoglycemic rats. Hyperglycemia caused an increase in both these flow values and in the duodenum. The increase in total pancreatic and duodenal blood flow was prevented by inhibition of COX-2 or non-selective COX inhibition. However, no effects on islet blood flow were seen after COX inhibition.

Conclusion. Inhibition of COX affects insulin release and blood glucose concentrations in vivo. However, COX inhibition has only minor effects on pancreatic islet blood flow, but prevents the glucose-induced increase in total pancreatic blood flow.     

Dexmedetomidine pretreatment alleviates propofol injection pain

Objective. The incidence of propofol injection pain during induction of general anesthesia varies from 28% to 90%. This prospective, randomized, double-blind, placebo-controlled study evaluated the effect of dexmedetomidine (DEX) for reducing the incidence and severity of propofol injection pain.

Methods. Patients undergoing elective surgical procedures were randomly allocated into seven groups of 30 patients each. Experimental treatments were intravenously administered over 10 min (total volume 10 mL) prior to intravenous propofol injection, as follows: group I, the control group, was given isotonic saline. Patients in groups II, III, and IV received DEX 0.25 µg/kg, 0.5 µg/kg, or 1.0 µg/kg, respectively, mixed with isotonic saline immediately before propofol injection. Patients in groups V, VI, and VII received DEX as above, but 5 minutes before propofol injection. Propofol consisted of 1% long-chain triglyceride propofol (2.5 mg/kg) injected at 1 mL/s.

Results. Median propofol injection pain score was 0.00 (IQR 0.00–3.00) in patients who received 1.0 µg/kg DEX 5 min before the propofol injection (group VII), and only 1 patient (of 30) in this group received a pain score >2. The median pain score and number of patients with pain scores >2 in group VII were both significantly less than in the control (group I; p = 0.000, both). There were no differences in either mean arterial pressure or heart rate at any time point after DEX injection among the groups.

Conclusions. Pretreatment with intravenous DEX 1 µg/kg 5 min prior to injection of long-chain triglyceride propofol is effective and safe in reducing the incidence and severity of pain due to propofol injection.     

Improved life satisfaction and pain reduction: Follow-up of a 5-week multidisciplinary long-term pain rehabilitation programme

Background.Multidisciplinary rehabilitation programmes can improve physical functioning and help patients with long-term pain back to work. Little is known, however, of the extent to which such rehabilitation also affects life satisfaction, pain severity, and disability. We wanted to evaluate if a 5-week rehabilitation programme for patients with long-term pain improves life satisfaction and decreases pain severity and disability.

Methods. The subjects were 164 patients aged 18–65 years from a pain rehabilitation clinic. Most of them were referred from primary care units. One group of repeated tests was used. Participants were asked to fill out the LiSat-11 checklist and parts of the Multidimensional Pain Inventory (MPI), including pain severity, at admission, at discharge, and 1 year after the rehabilitation programme.

Results. Satisfaction with life as a whole, and six of ten LiSat-11 domains improved during the follow-up, though none reached the levels for the general population. MPI subscales pain severity, pain interference, life control, and affective distress improved, whereas no change was observed for general activity. Patients older than 38 years decreased more in MPI affective distress than younger patients. Gender, pain severity, and work status before the programme did not significantly influence the outcome.

Conclusions. The results indicate that multidisciplinary rehabilitation improves life satisfaction, reduces pain severity, and reduces negative psychological, social, and behavioural effects of pain. These outcome variables relate to domains known to be of interest for patients and should therefore be considered for evaluation of rehabilitation programmes for long-term pain.     

The choice of anaesthetic—sevoflurane or propofol—and outcome from cancer surgery: A retrospective analysis

Background. Commonly used inhalational hypnotics, such as sevoflurane, are pro-inflammatory, whereas the intravenously administered hypnotic agent propofol is anti-inflammatory and anti-oxidative. A few clinical studies have indicated similar effects in patients. We examined the possible association between patient survival after radical cancer surgery and the use of sevoflurane or propofol anaesthesia.

Patients and methods. Demographic, anaesthetic, and surgical data from 2,838 patients registered for surgery for breast, colon, or rectal cancers were included in a database. This was record-linked to regional clinical quality registers. Cumulative 1- and 5-year overall survival rates were assessed using the Kaplan–Meier method, and estimates were compared between patients given propofol (n = 903) or sevoflurane (n = 1,935). In a second step, Cox proportional hazard models were calculated to assess the risk of death adjusted for potential effect modifiers and confounders.

Results. Differences in overall 1- and 5-year survival rates for all three sites combined were 4.7% (p = 0.004) and 5.6% (p < 0.001), respectively, in favour of propofol. The 1-year survival for patients operated for colon cancer was almost 10% higher after propofol anaesthesia. However, after adjustment for several confounders, the observed differences were not statistically significant.

Conclusion. Propofol anaesthesia might be better in surgery for some cancer types, but the retrospective design of this study, with uneven distributions of several confounders, distorted the picture. These uncertainties emphasize the need for a randomized controlled trial.     

Single-centre long-term follow-up of live kidney donors demonstrates preserved kidney function but the necessity of a structured lifelong follow-up

Background. The increase of live kidney donation (LKD) demands that we scrutinize its long-term consequences. Socialized medicine in Sweden has allowed us to survey long-term consequences of LKD with a high response rate.

Methods. Between 1974 and 2008, 455 LKDs were performed; 28 donors were deceased and 14 had moved abroad at the time of the survey. Of the remaining 413, 96% agreed to participate in a retrospective study with laboratory testing and answering a questionnaire.

Results. Mean age at donation was 49 ± 10 years, and the mean time since nephrectomy was 11 ± 7 years (range 1–33). No death was of renal cause. S-creatinine at follow-up was 93 ± 18 μmol/L, 28% had treated hypertension, of whom only 52% had BP <140/90. Eleven per cent had spot microalbuminuria, and 1% were diagnosed with diabetes mellitus. Seventy-one per cent had check-ups at least every second year, but 14% had no check-ups. Eighty per cent would be willing to donate again if it were possible, and only 3% regretted the donation.

Conclusion. Renal function is well preserved in the long term after donation, no case of end-stage renal disease was identified, and a large majority of our donors would donate again if it were possible. Although rates of microalbuminuria and hypertension were at expected levels, a significant number of donors demonstrated elevated blood pressure levels and inadequate antihypertensive treatment. A relatively large number of donors did not receive regular check-ups. Both of these issues demonstrate the need for a better-structured lifelong follow-up.     

Activation of adenosine receptors improves renal antioxidant status in diabetic Wistar but not SHR rats

Background. Diabetes and hypertension independently contribute to renal injury, and the major mechanisms involved are increased reactive oxygen species (ROS) bioavailability and renin-angiotensin system (RAS) activation. We investigated the role of adenosine in controlling ROS production and RAS activation associated with renal dysfunction in hypertension and diabetes.

Methods. Fourteen days after induction of diabetes with streptozotocin in 12-week-old male Wistar and spontaneously hypertensive (SHR) rats, animals were treated during 7 days with 2-chloroadenosine (CADO group, 5 mg/kg/d), a stable analogue of adenosine, or underwent a sham operation procedure. At the end of the study (day 21), intra-arterial systolic blood pressure (SBP) was measured, and 24-h urine and plasma samples and renal tissue were collected.

Results. CADO treatment decreased the plasma glucose concentration and glucose and protein excretion by more than 30% in both strains. CADO treatment decreased SBP in diabetic SHR rats (143 ± 8 versus 114 ± 4 mmHg, p < 0.05), but not in diabetic Wistar rats. The hypotensive effect of CADO was associated to a ～70% increase in plasma angiotensinogen (AGT) concentration and a ～50% decrease in urinary AGT excretion. CADO also caused a decrease in medullary and cortical hydrogen peroxide production of about 40%, which was associated with a proportional increase in glutathione peroxidase (GPx) activity in diabetic Wistar but not in diabetic SHR animals.

Conclusions. These results suggest that activation of adenosine receptors improves renal antioxidant capacity in diabetic Wistar but not SHR rats, although it improves glucose metabolism in both strains. Furthermore, activation of adenosine receptors does not seem to be directly influencing AGT production.     

A priming dose of intravenous ketamine-dexmedetomidine suppresses fentanyl-induced coughing: A double-blind,randomized, controlled study

Objective. This study was designed to investigate whether a priming dose of ketamine-dexmedetomidine can effectively suppress fentanyl-induced coughing (FIC).

Methods. Altogether 400 patients of ASA I and II, aged 18–70 years, undergoing various elective surgical procedures, were randomly allocated into four groups of 100 patients each. Patients in the placebo group received volume-matched normal saline 0.15 mL/kg + normal saline 0.05 mL/kg. One group of patients was given ketamine 0.15 mg/kg + normal saline 0.05 ml/kg (KET), and another group dexmedetomidine 0.5 μg/kg + normal saline 0.05 ml/kg (DEX). Finally, one group of patients received ketamine 0.15 mg/kg + dexmedetomidine 0.5 μg/kg (KETODEX). After fentanyl administration, the onset time and severity of cough for 1 min were recorded. Cough severity was graded as mild (grade 1–2), moderate (grade 3–5), or severe (grade >5).

Result. The incidence of FIC was 53%, 34%, 20%, and 9% in the placebo, DEX, KET, and KETODEX groups, respectively. The incidence of cough was significantly lower in the KETODEX group. Likewise, the onset time of cough was significantly delayed in the KETODEX group. Only nine patients in the KETODEX group had either mild (6%) or moderate (3%) cough, with none suffering from severe cough.

Conclusion. A priming dose of KETODEX effectively suppressed the cough reflex induced by fentanyl and delayed the onset time of cough. Therefore, treatment with KETODEX may be a clinically useful method for preventing FIC.     

Outcome from spontaneous subarachnoid haemorrhage—results from 2007–2011 and comparison with our previous series

Objectives. The management of patients with spontaneous subarachnoid haemorrhage (SAH) has changed, in part due to interventions now being extended to patients who are older and in a worse clinical condition. This study evaluates the effects of these changes on a complete 5-year patient material.

Methods. Demographic data and results from 615 patients with SAH admitted from 2007 to 2011 were put together. Aneurysms were found in 448 patients (72.8%). They were compared with the aneurysm group (n = 676) from a previously published series from our centre (2001–2006). Linear regression was used to determine variables predicting functional outcome in the whole aneurysm group (2001–2011).

Results. Patients in the more recent aneurysm group were older, and they were in a worse clinical condition on admission. Regarding younger patients admitted in World Federation of Neurosurgical Societies SAH grading (WFNS) 3, there were fewer with a good outcome. In the whole aneurysm group 2001–2011, outcome was best predicted by age, clinical condition at admission, and the size of the bleeding, and not by treatment mode or localization of aneurysm.

Conclusion. It seems important for the outcome that aneurysms are treated early. The clinical course after that depends largely on the condition of the patient on admission rather than on aneurysm treatment method. This, together with the fact that older patients and those in worse condition are now being admitted, increases demands on neurointensive care. Further improvement in patient outcome depends on better understanding of acute brain injury mechanisms and improved neurointensive care as well as rehabilitation measures.     

Transthyretin-derived amyloidosis: Probably a common cause of lumbar spinal stenosis

Background. Senile systemic amyloidosis (SSA) derived from wild-type transthyretin is a fairly common condition of old individuals, particularly men. The main presentation is by cardiac involvement, which can lead to severe restrictive cardiomyopathy. SSA is, however, a systemic disease, and amyloid deposits may appear in many other tissues but are thought to be without clinical symptoms outside the heart. Amyloid is a very common finding in cartilage and ligaments of elderly subjects, and transthyretin has been demonstrated in some deposits. Lumbar spinal stenosis is also a condition of usually elderly individuals in whom narrowing of the lumbar spinal canal leads to compression of nerves to the lower limbs.

Results. We questioned whether lumbar spinal stenosis sometimes could be a manifestation of undiagnosed SSA. In this first report we have studied the presence of amyloid in material obtained at surgery for spinal stenosis in 26 patients. Amyloid was found in 25 subjects. Transthyretin was demonstrated immunohistochemically in 5 out of 15 studied resected tissues. Four of the positive materials were analyzed with Western blot revealing both full-length transthyretin (TTR) and C-terminal TTR fragments, typically seen in SSA.

Conclusion. We conclude that lumbar spinal stenosis quite frequently may be a consequence of SSA and that further studies are warranted.     

A ventilation strategy during general anaesthesia to reduce postoperative atelectasis

Background. Atelectasis is common during and after general anaesthesia. We hypothesized that a ventilation strategy, without recruitment manoeuvres, using a combination of continuous positive airway pressure (CPAP) or positive end-expiratory pressure (PEEP) and a reduced end-expiratory oxygen fraction (F_ETO₂) before ending mask ventilation with CPAP after extubation would reduce the area of postoperative atelectasis.

Methods. Thirty patients were randomized into three groups. During induction and emergence, inspiratory oxygen fractions (F_IO₂) were 1.0 in the control group and 1.0 or 0.8 in the intervention groups. No CPAP/PEEP was used in the control group, whereas CPAP/PEEP of 6 cmH₂O was used in the intervention groups. After extubation, F_IO₂ was set to 0.30 in the intervention groups and CPAP was applied, aiming at F_ETO₂ < 0.30. Atelectasis was studied by computed tomography 25 min postoperatively.

Results. The median area of atelectasis was 5.2 cm² (range 1.6–12.2 cm²) and 8.5 cm² (3–23.1 cm²) in the groups given F_IO₂ 1.0 with or without CPAP/PEEP, respectively. After correction for body mass index the difference between medians (2.9 cm²) was statistically significant (confidence interval 0.2–7.6 cm², p = 0.04). In the group given F_IO₂ 0.8, in which seven patients were ex- or current smokers, the median area of atelectasis was 8.2 cm² (1.8–14.7 cm²).

Conclusion. Compared with conventional ventilation, after correction for obesity, this ventilation strategy reduced the area of postoperative atelectasis in one of the intervention groups but not in the other group, which included a higher proportion of smokers.