[Provision of information to patients. Legal and humanitarian requirements]

Any treatment to which the patient has not expressly consented constitutes an assault according to our legal system. The patient's agreement is therefore necessary for every elective treatment. Patients cannot give meaningful consent until they have received detailed information on their illness, its presumed course, the treatment options and the risks they are exposed to both with and without treatment. This requires provision of information to allow self-determination. The requirement for the patient alone to make decisions arises from the personal rights in our [German] Constitution. If the information provided has been inadequate the doctor is liable for all negative--including life-changing-consequences, regardless of whether or not the risk that has been realised is one that is expressly required to be explained. The Federal Court of Justice requires the doctor to address each patient's personality and their fate when providing information (BGH, NHW 1983, 328, 329). It is not permissible for the duty to provide information to be delegated to a third party unless strict obligations are fulfilled (BGH 7.11.2006 VI ZR 206/05).

What is the significance in routine care of c-ANCA/PR3-ANCA in the absence of systemic vasculitis? A case series

OBJECTIVE

ANCA has come to play an important role in diagnosing vasculitis. In selected populations c-ANCA/PR3-ANCA has a high specificity and sensitivity for vasculitis. In clinical practice, how individuals with c-ANCA/PR3-ANCA but without sufficient evidence of systemic vasculitis should be managed is unclear. We therefore retrospectively assessed the disease panorama and outcome in a consecutive series of individuals with c-ANCA/PR3-ANCA, and studied in detail those individuals who turned out not to fulfil criteria for vasculitic disease.

METHODS

The study population consisted of 74 consecutive patients who all had a positive test for C-ANCA and PR3-ANCA between 1992 and 2002 at the Immunology laboratory at Uppsala University Hospital, Sweden. The patients' medical files were reviewed and their diagnosis re-evaluated through June 2006.

RESULTS

18 of the 74 ANCA-positive individuals did not present clinical evidence supportive of, or insufficient to support, a diagnosis of systemic vasculitis, but presented a range of other diseases. During a mean follow-up of 6.8 years, none of these 18 patients developed vasculitis.

CONCLUSIONS

Individuals with a positive c-ANCA and PR3-ANCA but no vasculitis at the time of testing run an unknown but likely small risk of later developing vasculitis. In this group, a positive ANCA may represent background noise (borderline titres) or be a marker of inflammatory activity rather than of vasculitic disease (high titres).

Parkinson's disease and other basal ganglia or movement disorders in a large nationwide cohort of Swedish welders

INTRODUCTION

Although it has been hypothesised that metal welding and flame cutting are associated with an increased risk for Parkinson's disease due to manganese released in the welding fume, few rigorous cohort studies have evaluated this risk.

METHODS

The authors examined the relation between employment as a welder and all basal ganglia and movement disorders (ICD-10, G20-26) in Sweden using nationwide and population based registers. All men recorded as welders or flame cutters (n = 49,488) in the 1960 or 1970 Swedish National Census were identified and their rates of specific basal ganglia and movement disorders between 1964 and 2003 were compared with those in an age and geographical area matched general population comparison cohort of gainfully employed men (n = 489,572).

RESULTS

The overall rate for basal ganglia and movement disorders combined was similar for the welders and flame cutters compared with the general population (adjusted rate ratio (aRR) = 0.91 (95% CI 0.81 to 1.01). Similarly, the rate ratio for PD was 0.89 (95% CI 0.79 to 0.99). Adjusted rate ratios for other individual basal ganglia and movement disorders were also not significantly increased or decreased. Further analyses of Parkinson's disease by attained age, time period of follow up, geographical area of residency, and educational level revealed no significant differences between the welders and the general population. Rates for Parkinson's disease among welders in shipyards, where exposures to welding fumes are higher, were also similar to the general population (aRR = 0.95; 95% CI 0.70 to 1.28).

CONCLUSION

This nationwide record linkage study offers no support for a relation between welding and Parkinson's disease or any other specific basal ganglia and movement disorders.

Endovascular treatment of intracerebral arteriovenous malformations: procedural safety, complications, and results evaluated by MR imaging, including diffusion and perfusion imaging

BACKGROUND AND PURPOSE

Endovascular embolization is an increasingly common method to treat intracerebral arteriovenous malformations (AVM). To date, however, published data are rather scarce, especially with regard to true procedure-related complications and their causes. The purpose of our study was to evaluate treatment safety and correlate anatomic results with clinical outcome by using MR imaging, including diffusion-weighted (DWI) and perfusion imaging (PI).

METHODS

We performed 50 endovascular procedures in 21 patients. Most AVMs were supratentorial, Spetzler-Martin grades II-IV. MR imaging was scheduled within 1 week before and 3 days after each treatment. MR imaging findings were correlated to digital subtraction angiography, procedure reports, and the clinical course. Outcome was graded according to the modified Rankin scale (mRS) 3-6 months after treatment.

RESULTS

In this study, 104 MR imaging examinations were performed; mean interval between the endovascular procedure and posttreatment MR imaging was 28 hours. Nine adverse events occurred in 7 patients during 8 procedures (16%), one causing a permanent deficit. New lesions were noted on MR imaging after 22/50 procedures. Ischemic lesions in 22% of the procedures, frequently located perinidally. Most lesions were small, frequently asymptomatic, and reversible (18/23). Four hematomas were found. Subacute hemorrhages developed from a vasogenic edema on 2 occasions. New lesions, including hematomas, developed between treatments in 4 patients, mainly because of progressive occlusion of the nidus or draining veins. PI overestimated the AVM nidus on most occasions, and transient worsening of the PI pattern was noted in 2 patients. Treatment-related mortality and morbidity were 0% and 14.2%, respectively (mRS 1-2).

CONCLUSIONS

Endovascular procedures are rather safe but are associated with more ischemic events and followed by less hemodynamic disturbances than previously understood. Adverse procedural events and new MR imaging lesions were generally asymptomatic and most often transient, if symptomatic. Most lesions would not have been verified without MR imaging. DWI and PI were most useful to detect and understand the cause of various complications. The most clinically important complications were caused by late venous occlusions.

Impact of parental history on patients' cardiovascular mortality in rheumatoid arthritis

BACKGROUND

Patients with rheumatoid arthritis are at increased risk of death from cardiovascular disease (CVD). This risk is influenced by the inflammatory activity of the rheumatoid arthritis as well as by traditional risk factors for CVD. However, little is known about whether or to what extent hereditary factors for CVD contribute additional risk in patients with rheumatoid arthritis.

OBJECTIVE

To assess the clinical impact of a parental history of CVD in patients with rheumatoid arthritis.

METHODS

Population based cohort study of 10,805 Swedish patients with rheumatoid arthritis aged 16-67 years during follow up (1990-2000). Parents, and cardiovascular deaths among patients and parents, were identified through register linkages. Relative risk of death v the general population was assessed using standardised mortality ratios (SMR), which were compared by Poisson regression.

RESULTS

Rheumatoid patients with a parental history of fatal CVD had an SMR of death from CVD of 2.9 (95% confidence interval, 2.5 to 3.4). By contrast, rheumatoid patients without a parental history of fatal CVD had an SMR of 1.7 (1.2 to 2.3). A parental death from CVD was associated with a 70% increase in the risk of fatal CVD in rheumatoid arthritis (SMR ratio = 1.7 (1.2 to 2.4), and an increase in the 10 year mortality from CVD from 5% to 10% in men and from 2% to 4% in women aged 50 to 67 years.

CONCLUSIONS

Parental history of death from CVD is an important (and easily assessable) risk factor for fatal CVD in rheumatoid arthritis.

Diffusion and perfusion MRI in patients with ruptured and unruptured intracranial aneurysms treated by endovascular coiling: complications, procedural results, MR findings and clinical outcome

Our purpose was to evaluate treatment safety as well as complications frequency and management in endovascular coiling of intracerebral aneurysms using MR diffusion and perfusion imaging. In this prospective study, 77 MR examinations were performed in conjunction with 43 procedures in 40 patients, 14 patients presented with ruptured and 26 with unruptured aneurysms. Mean time interval between treatment and post-procedure MRI was 29 and 25 h for the ruptured and unruptured aneurysm group, respectively. Peri-procedural complications, including five major events and five minor transient events, occurred in 10/43 procedures (23%), necessitating thrombolytic therapy in two patients and angioplasty in one, all three within the unruptured aneurysm group. Fifty-one new lesions were found on post-treatment DWI and 47 of them were regarded as of ischemic origin. Most lesions were small (<3 mm), ipsilateral to the treated aneurysm and asymptomatic (37/40 patients). Sixty-seven percent of the lesions were found in the ruptured and 33% in the unruptured aneurysm group. The ischemic lesions did occur more frequently in patients treated for aneurysm of large neck size and according to the remodelling technique. The overall morbidity and mortality rates were 14.6 and 7.3% whereas morbidity and mortality rates related to the technique were only 2.6 and 0%, respectively. Silent embolism seems to be more common than clinically evident and partially related to patient presentation, heparinazation and treatment strategy. The capability to depict early complications and analyse their potential causes by using MR with DWI has been of great importance in our modification and improvement of therapeutic protocols, evaluations and strategies.

Propofol-induced calcium signalling and actin reorganization within breast carcinoma cells

BACKGROUND AND OBJECTIVE

MDA-MB-468 breast carcinoma cells respond to non-volatile anaesthetics such as propofol with an increased migration. Here we investigated the relationship between GABA-A receptor modulators, the mode of calcium oscillation and actin reorganization with regard to breast carcinoma cell migration.

METHODS

Expression of the GABA-A receptor was determined by Western blot analysis. Calcium-imaging experiments of individual MDA-MB-468 cells as well as visualization of the F-actin distribution were performed by confocal laser scanning microscopy. Cell migration was investigated in a three-dimensional collagen matrix by time-lapse video microscopy. The GABA agonist propofol was used in a final concentration of 6 microg mL(-1). GABA-A receptor antagonist bicuculline (50 micromol) and selective L-type calcium channel blocker verapamil (5 micromol) were used to modulate the propofol effects.

RESULTS

A functional GABA-A receptor is expressed by MDA-MB-468 cells. Activation with propofol resulted in sustained increased intracellular calcium concentrations concomitant with actin reorganization and induction of migration in MDA-MB-468 cells. These propofol effects were completely blocked by verapamil. Spontaneous migration of MDA-MB-468 cells (64.4 +/- 7.0%) was significantly increased by propofol to 85.0 +/- 5.0%. MDA-MB-468 cells co-treated with propofol and verapamil showed a migratory activity of 63.0 +/- 2.0% indicating that verapamil blocked the propofol effect. Similar results were achieved with the GABA-A receptor inhibitor bicuculline (control: 56.3 +/- 8.5%; propofol: 80.5 +/- 7.1%; propofol + bicuculline: 52.5 +/- 8.6%).

CONCLUSION

Activation of GABA-A receptor by propofol correlated with an increased migration of MDA-MB-468 breast carcinoma cells, mediated by calcium influx via L-type calcium channels and reorganization of the actin cytoskeleton.

Risk of haematopoietic cancer in patients with inflammatory bowel disease

BACKGROUND AND AIMS

Several chronic inflammatory conditions are associated with an increased risk of lymphoma. Whether this applies to inflammatory bowel disease (IBD) is still unclear but of paramount interest, particularly in the safety evaluation of newer immunosuppressive drugs. Reports also indicate a possible increase in the risk of leukaemia in IBD. We therefore assessed the risk of haematopoietic cancers in a large cohort of patients with IBD.

SUBJECTS AND METHODS

We performed a population based cohort study using prospectively recorded data, including 47 679 Swedish patients with Crohn's disease (CD) or ulcerative colitis (UC) assembled from regional cohorts of IBD from 1955 to 1990 (n = 8028) and from the Inpatient Register of 1964-2000 (n = 45 060), with follow up until 2001. Relative risks were expressed as standardised incidence ratios (SIR).

RESULTS

Overall, we observed 264 haematopoietic cancers during follow up, which corresponded to a borderline significant 20% increased risk in both UC and CD. In UC, lymphomas occurred as expected (SIR 1.0, n = 87) but myeloid leukaemia occurred significantly more often than expected (SIR 1.8, n = 32). In CD, there was a borderline significant increased lymphoma risk (SIR 1.3, n = 65), essentially confined to the first years of follow up. Proxy markers of disease activity had little impact on lymphoma risk.

CONCLUSION

On average, patients with IBD have a marginally increased risk of haematopoietic cancer. In UC, this is accounted for by an excess of myeloid leukaemia. In CD, a modest short term increase in the risk of lymphoma of unknown significance cannot be excluded but any long term risk increase seems unlikely.

Haematopoietic malignancies in rheumatoid arthritis: lymphoma risk and characteristics after exposure to tumour necrosis factor antagonists

BACKGROUND

Patients with rheumatoid arthritis (RA) are at increased risk of malignant lymphomas, and maybe also of leukaemia and multiple myeloma. The effect of tumour necrosis factor (TNF) antagonists on lymphoma risk and characteristics is unclear.

OBJECTIVE

To assess expected rates and relative risks of haematopoietic malignancies, especially those associated with TNF antagonists, in large population based cohorts of patients with RA.

METHODS

A population based cohort study was performed of patients with RA (one prevalent cohort (n = 53,067), one incident cohort (n = 3703), and one TNF antagonist treated cohort 1999 through 2003 (n = 4160)), who were linked with the Swedish Cancer Register. Additionally, the lymphoma specimens for the 12 lymphomas occurring in patients with RA exposed to TNF antagonists in Sweden 1999 through 2004 were reviewed.

RESULTS

Study of almost 500 observed haematopoietic malignancies showed that prevalent and incident patients with RA were at increased risk of lymphoma (SIR = 1.9 and 2.0, respectively) and leukaemia (SIR = 2.1 and 2.2, respectively) but not of myeloma. Patients with RA treated with TNF antagonists had a tripled lymphoma risk (SIR = 2.9) compared with the general population. After adjustment for sex, age, and disease duration, the lymphoma risk after exposure to TNF antagonists was no higher than in the other RA cohorts. Lymphomas associated with TNF antagonists had characteristics similar to those of other RA lymphomas.

CONCLUSION

Overall, patients with RA are at equally increased risks for lymphomas and leukaemias. Patients with RA treated with TNF antagonists did not have higher lymphoma risks than other patients with RA. Prolonged observation is needed to determine the long term effects of TNF antagonists on lymphoma risk.

Risks of solid cancers in patients with rheumatoid arthritis and after treatment with tumour necrosis factor antagonists

BACKGROUND

Existing studies of solid cancers in rheumatoid arthritis (RA) reflect cancer morbidity up until the early 1990s in prevalent cohorts admitted to hospital during the 1980s.

OBJECTIVE

To depict the cancer pattern of contemporary patients with RA, from updated risk data from prevalent and incident RA populations. To understand the risk of solid cancer after tumour necrosis factor (TNF) treatment by obtaining cancer data from cohorts treated in routine care rather than trials.

METHODS

A population based study of three RA cohorts (one prevalent, admitted to hospital 1990-2003 (n = 53,067), one incident, diagnosed 1995-2003 (n = 3703), and one treated with TNF antagonists 1999-2003 (n = 4160)), which were linked with Swedish nationwide cancer and census registers and followed up for cancer occurrence through 2003.

RESULTS

With 3379 observed cancers, the prevalent RA cohort was at marginally increased overall risk of solid cancer, with 20-50% increased risks for smoke related cancers and +70% increased risk for non-melanoma skin cancer, but decreased risk for breast (-20%) and colorectal cancer (-25%). With 138 cancers, the incident RA cohort displayed a similar cancer pattern apart from non-decreased risks for colorectal cancer. TNF antagonist treated patients displayed solid cancer (n = 67) risks largely similar to those of other patients with RA.

CONCLUSION

The cancer pattern in patients treated with TNF antagonists mirrors those of other contemporary as well as historic RA cohorts. The consistent increase in smoking associated cancers in patients with RA emphasises the potential for smoking cessation as a cancer preventive measure in RA.

Vertebrobasilar dissection with subarachnoid hemorrhage: a retrospective study of 29 patients

We have reviewed initial diagnostic features, treatment, and outcome in 29 patients with acute subarachnoid hemorrhage due to non-traumatic vertebrobasilar artery dissection diagnosed in our hospital between 1993 and 2003. The dissections occurred in the vertebral artery in 19 patients, the posterior inferior cerebellar artery (PICA) in two patients, the basilar artery in four patients, and in the vertebral artery extending into the PICA in four patients. A pseudoaneurysm was found in 20 patients. Clinical manifestations typically included sudden onset of moderate to severe headache, nuchal rigidity, and drowsiness. Fourteen patients were treated conservatively. Fifteen patients underwent endovascular treatment with either parent artery occlusion (13 patients) or aneurysmal coil occlusion with preservation of the parent artery (2 patients). Re-bleeding occurred within 12 days and before treatment in nine patients. Eight of these had a pseudoaneurysm. No patient bled after endovascular treatment. Poor grade and early re-bleeding were associated with less favorable outcome. Outcome at 6 months did not differ significantly between endovascular and conservative treatment. Altogether, good recovery was achieved for 16 patients, moderate disability was seen in one, severe disability in four, and eight patients (27%) died. The absence of bleeding subsequent to endovascular treatment in this study suggests that endovascular treatment may be a rational approach in these patients at high risk of re-bleeding, especially those with a pseudoaneurysm.

The influence of remaining live BCG organisms in vaccinated mice on the maintenance of immunity to tuberculosis

The only available vaccine against Mycobacterium tuberculosis, the bacille Calmette-Guérin (BCG) vaccine, is at present being used as a reference for the efficacy of novel vaccines. Herein, we demonstrate that viable BCG can be detected at late time points after vaccination in C57BL/6J mice. If BCG is cleared by antibiotic treatment, the number of mycobacteria-reactive effector cells in the spleen gradually reverts to low levels and consequently immunity in this organ wanes, while resistance in the lung remains stable. The implications for comparing BCG vaccination with experimental vaccines including non-replicating vaccines are discussed.

Risk of non-Hodgkin's lymphoma and skin malignancies in patients diagnosed with cataract

The rapid increase of non-Hodgkin's lymphoma (NHL) in industrialized countries is yet unexplained. Ultraviolet radiation (UVR) has been suggested as an aetiologic factor due to observed elevated risks of cutaneous malignancies after NHL and vice versa. Cataract, as related to UVR, was tested as a proxy variable to further elucidate this observation. Cataract in-patients (n = 49914) reported to the Swedish Patient Register and later developing NHL and cutaneous malignancies were identified by record linkage to the Swedish Cancer Registry. The observed number of malignancies among cataract patients did not differ significantly from that expected in the general population. In contrast, the risk of cutaneous malignant melanoma was lower than anticipated, based on Swedish background incidence figures. The results did not give support for a causal relationship between NHL and UVR.

Selective diagnostic cervical nerve root block--correlation with clinical symptoms and MRI-pathology

BACKGROUND

The aim of this study is to describe the method of a cervical selective diagnostic nerve root block (SNRB) technique and assess its ability to correlate clinical symptoms with MRI findings in patients with cervical radicular pain and a single level degenerative disease.

METHODS

Twenty consecutive patients with cervical radiculopathy and correlating single level MRI pathology were studied. All patients underwent clinical investigation and neck and arm pain measurement with visual analog scales (VAS). The last 10 consecutive patients also underwent provocation with active neck motion when arm and neck pain were measured. They all underwent SNRB and 1 ml local-anesthesia (Mepivacaine 10 mg/ml) was injected, with the aid of fluoroscopy, close to the nerve-root. The VAS estimation and clinical investigation including provocation were repeated 30 minutes after the block. Criteria for a positive block response are a significant subjective pain reduction and at least 50% VAS pain reduction in the arm.

FINDINGS

For the whole group mean VAS arm pain reductions were 86% and mean VAS neck pain reductions were 65%. When the results from the provocation were added all patients had a positive block. Eighteen were operated on by an anterior procedure and all 18 were free from radicular pain at follow up.

INTERPRETATION

The block procedure seems relevant for revealing a relationship between radiological pathology and clinical symptoms and signs.

Fatigue after aneurysmal subarachnoid hemorrhage evaluated by pituitary function and 3D-CBF

OBJECTIVE

The reason for longstanding fatigue following aneurysmal subarachnoidal hemorrhage (SAH) is still not clarified. The bleed from supratentorial aneurysms is often in the vicinity of the hypothalamus and pituitary gland making an endocrine dysfunction plausible.

METHODS

Ten patients with post-SAH fatigue were investigated with 3D-CBF (SPECT) and underwent an evaluation of the pituitary function.

RESULTS

Five had normal pituitary function. Disturbances in the gonadotropin function was detected in three patients and suspected in two. The mean insulin-like growth factor I (IGF-I) value of the patients was in the lower part of the reference range. In the patients with endocrine dysfunction, the 3D-CBF was pathologic in the central structures of the basal region.

CONCLUSIONS

The present results indicate that an aneurysmal SAH may result in partially impaired pituitary capacity. This deficit may contribute to fatigue after aneurysmal SAH, but cannot solely explain this disorder. SPECT identified regional tissue damage in the patients with pituitary dysfunction after SAH.

C-reactive protein levels following standard neurosurgical procedures

BACKGROUND

The aim of the present study was to establish the magnitude and time-course of C-reactive protein increases following routine neurosurgical procedures in the absence of clinical and laboratory signs of infection.

METHOD

C-reactive protein levels were studied daily following ventriculo-peritoneal shunt implantation, anterior cervical fusion, vestibular schwannoma operation, supratentorial glioma surgery, endovascular intracranial aneurysm treatment and open cerebral aneurysm surgery.

FINDINGS

The magnitude of the C-reactive protein increase depended on the extent of surgical trauma and peak-levels were recorded between postoperative day one and four after which the levels tapered off.

INTERPRETATION

Increases occurring after the fourth postoperative day are likely to be caused by complications of surgery, e.g. infection.

Influence of non-volatile anesthetics on the migration behavior of the human breast cancer cell line MDA-MB-468

BACKGROUND

Anesthetic agents are known to influence functions of the immune system. Anesthetic drugs also support cancer progression by suppressing the activity of immune cells. In breast carcinoma an increase in expression of peripheral-type benzodiazepine receptors (PBR) and the gamma aminobutyl acid (GABA) level has been discovered. Therefore, an investigation of a direct influence of GABA-A agonist propofol, GABA-A and PBR-agonist etomidate, and the local anesthetic drug lidocaine, which can also bind to the GABA-A receptor and PBR, on migration of breast carcinoma cells was performed.

METHODS

MDA-MB-468 cells were incubated with anesthetic agents using clinically relevant concentrations (propofol 3, 6, 9 mg/l, etomidate 2, 3, 4 mg/l, and lidocaine 1.25, 2.5, 5 mg/l). Locomotion was investigated in a three-dimensional collagen matrix using time-lapse video microscopy and computer-assisted cell-tracking.

RESULTS

The percentage of migrating cells (57.4+/-1.9) as well as the velocity (0.22+/-0.09 microm/min) and distance migrated (89.4+/-66.8 microm/10 h) increased in the presence of propofol in a dose-dependent manner (up to 74.4+/-7.5, 0.30+/-0.09, 143.8+/-89.1, respectively) compared with the long chain triglyceride (LCT) control. In contrast, no influence of etomidate on the number of migrating cells could be observed. The velocity and distance migrated at 3 and 4 mg/l were found to be statistically significantly enhanced. Treatment with lidocaine caused an increase in the percentage of migrating cells (up to 75.0+/-5.6) in velocity dose dependently (up to 0.33+/-0.06) and in distance migrated (up to 151.5+/-92.9).

CONCLUSION

These results show that different anesthetic drugs are able to modulate the migratory machinery of human breast carcinoma cells in vitro.

Effects of iso- and hypervolemic hemodilution on regional cerebral blood flow and oxygen delivery for patients with vasospasm after aneurysmal subarachnoid hemorrhage

BACKGROUND

Arterial vasospasm after subarachnoid hemorrhage may cause cerebral ischemia. Treatment with hemodilution, reducing blood viscosity, and hypervolemia, increasing cardiac performance and distending the vasospastic artery, are clinically established methods to improve blood flow through the vasospastic arterial bed.

METHOD

Eight patients with transcranial Doppler verified vasospasm after subarachnoid hemorrhage were investigated with global (two-dimensional (133)Xenon) and regional (three-dimensional (99 m)Tc-HMPAO) cerebral blood flow (CBF) measurements, before and after 1/iso- and 2/hypervolemic hemodilution. Hematocrit was reduced to 0.28 from 0.36. Hypervolemia was achieved by increasing blood volume by 1100 ml.

FINDINGS

Isovolemic hemodilution increased global cerebral blood flow from 52.25+/-10.12 to 58.56+/-11.73 ml * 100 g(-1) * min(-1) (p<0.05), but after hypervolemic hemodilution CBF returned to 51.38+/-11.34 ml * 100 g(-1) * min(-1). Global cerebral delivery rate of oxygen (CDRO(2)) decreased from 7.94+/-1.92 to 6.98+/-1.66 ml * 100 g(-1) * min(-1) (p<0.001) during isovolemic hemodilution and remained reduced, 6.77+/-1.60 ml * 100 g(-1) * min(-1) (p<0.001), after the hypervolemic hemodilution. As a test of the hemodilution effect on regional CDRO(2) an ischemic threshold was defined as the maximal amount of oxygen transported by a CBF of 10 ml * 100 g(-1) * min(-1) at a Hb 140 g/l which corresponds to a CDRO(2) of 1.83 ml * 100 g(-1) * min(-1). The brain volume with a CDRO(2) exceeding the ichemic threshold was 1300+/-236 ml before intervention. After isovolemic hemodilution the non-ischemic brain volume was reduced to 1206+/-341 (p<0,003). After hypervolemic hemodilution the non-ischemic brain volume remained reduced at 1228+/-347 ml (p<0.05).

INTERPRETATION

The present study of controlled isovolemic hemodilution demonstrated increased global CBF, but there was a pronounced reduction in oxygen delivery capacity. Both CBF and CDRO(2) remained decreased during further hypervolemic hemodilution. We conclude that hemodilution to hematocrit 0.28 is not beneficial for patients with cerebral vasospasm after SAH.

[Systemic infections of dental origin]

Microorganisms harbored in the oral cavity have long been recognized to cause systemic disease with a well known mechanism of spread via the blood stream. Different factors, including the presence of periodontal disease, the number of dental extractions or the duration of dental surgery have an influence on the risk of bacteremia. Infectious endocarditis is classically cited, but there are other potential problems including brain abscess, meningitis, lung or lie abscess, and even for some authors, a risk of thrombotic heart disease. It is important to keep in mind that some of these focal infections may be possible complications of dental (or buccal) infection. Prevention is crucial.