Successful treatment of an aciclovir-resistant herpes simplex type 2 infection with cidofovir in an AIDS patient

Management of the increasing frequency of aciclovir-resistant herpes simplex virus (HSV) infections among immunocompromised human immunodeficiency virus-infected people demands additional treatment options. We report the case of a 38-year-old patient with acquired immune deficiency syndrome who suffered from a perianal butterfly ulcer, which was HSV-2 positive by polymerase chain reaction (PCR) analysis. The ulcer appeared during treatment of a cytomegalovirus (CMV) pneumonitis with ganciclovir. Despite additional valaciclovir therapy the lesion gradually progressed in size. Investigations including histology, PCR analysis and in situ hybridization of a biopsy from the growing ulcer margin confirmed the presence of HSV-2 infection. Importantly, HSV isolates from this specimen were resistant to aciclovir. Based on a report about the successful treatment of aciclovir-resistant HSV infection with cidofovir, our patient received this drug intravenously at a dose of 5 mg kg-1 body weight once weekly for a total of 3 weeks. Concomitant oral probenecid and prehydration were administered to minimize nephrotoxicity. Within 30 days of treatment the ulcer had almost (> 95%) completely healed. We conclude that cidofovir is a potent antiviral drug with a potential usefulness in the treatment of aciclovir-resistant HSV-2 infection. It deserves further investigation in clinical trials.

Malignant lymphoma of the cranial vault in an HIV-positive patient: imaging findings

We describe the CT and MR imaging findings in an HIV-positive patient with malignant non-Hodgkin's lymphoma of the cranial vault, a rare site for lymphoma involvement. Autopsy revealed lymphomatous bone lesions, lymphoma in the epidural space, and a large necrotic lymphoma in the soft tissue of the skull.

Olfactory function in HIV-positive subjects

The aim of this study was to reinvestigate previous reports of chemosensory dysfunction in HIV-positive subjects. Odor thresholds, odor discrimination and odor identification were assessed using the Sniffin' Sticks test battery. Seventy-four HIV-positive patients were tested. According to CDC criteria, 38 subjects were classified as stage A, 10 as stage B and 26 as stage C. None of the subjects exhibited severe cognitive impairment. Compared to normative data all subjects had normal odor identification and discrimination. However, odor thresholds were well below the median of a normal population. There were no significant differences between stage A, B or C subjects. This may be interpreted as indicating that olfactory dysfunction is among the primary deficits of HIV infection and occurs independently of disease stage. These results confirm previous work suggesting that odor thresholds are elevated early in HIV infection whereas a decline in identification and discrimination abilities is correlated with reduced cognitive abilities.

Highly active antiretroviral therapy responders exhibit a phenotypic lymphocyte pattern comparable to that of long-term nonprogressors

BACKGROUND

The implementation of highly active antiretroviral therapy (HAART) in patients with progressive HIV-1 disease has resulted in a marked reduction of HIV-1-associated morbidity and mortality. In fact, the risk of HAART responders to develop opportunistic infections becomes similar to that of long-term nonprogressors (LTNPs).

METHODS

Reasoning that HAART may ultimately have consequences on both the quantity and quality of immune responses of a HIV-1-infected person, we assessed CD4+ and CD8+ T cell subsets in HAART recipients over a time period of 15 months and compared them to the lymphocyte phenotype of LTNPs and healthy controls. Evaluations included quantitative determinations of memory (CD45RO+CD62L-), naive (CD45RO-CD62L+), effector (CD27-, CD28-) and activated (HLA-DR+, CD38+, CD95+) CD4+ and CD8+ lymphocytes. The T cell function was assayed by skin tests.

RESULTS

Compared to healthy persons, treatment-naive patients with progressive disease exhibited a considerable reduction of CD4+ T cells with many of the remaining T cells showing signs of activation at baseline. CD8+ T cells were greatly increased in number, mainly because of an expansion of CD28- effector and memory CD8+ T cells. LTNPs, in contrast, had stable CD4+ and elevated CD8+ T cell counts, the latter being mainly due to a marked increase in CD27- effector cells. Essentially, the same immunophenotype was seen in HAART responders after 15 months of treatment when compared to LTNPs.

CONCLUSIONS

It is tempting to speculate that a HAART-induced reduction in viral load may influence the immune system's capacity to mount protective responses to pathogenic microorganisms.

Ocular blood flow in patients infected with human immunodeficiency virus

PURPOSE

Alterations of ocular blood flow may play a role in the pathophysiology of human immunodeficiency virus (HIV) related retinal microvasculopathy. In this study ocular blood flow was investigated in patients with HIV infection.

DESIGN

In a prospective, cross-sectional study ocular blood flow was measured in 37 eyes of consecutive HIV- infected persons and compared with the data of age-matched healthy controls. This sample size was calculated based on an alpha-error of 0.5 and a beta-error of 0.8.

METHODS

Macular white blood cell flow, fundus pulsation amplitude, and blood flow velocities in the retrobulbar vessels were measured with blue field entoptic technique, laser interferometry, and Doppler sonography, respectively. Immunologic and ophthalmologic status was evaluated from each patient.

RESULTS

Mean CD4+ cell count of the HIV-infected persons was 206.8 +/- 145.6 cells/mm(3). In five patients HIV-related retinopathy was observed. A significant reduction in leukocyte density was seen in HIV infected persons (82.2 +/- 23.4) as compared with the control group (102.0 +/- 28.4; P =.019). The resistive index in the central retinal artery was higher in HIV infected patients (0.77 +/- 0.05) as compared with the controls (0.74 +/- 0.04; P =.04). The other hemodynamic parameters were not different between groups. No correlation of flow parameters and CD4+ cell count or HIV-related retinopathy was observed.

CONCLUSIONS

Decreased macular leukocyte density was detected in HIV infected persons. Our study suggests that abnormal retinal hemodynamics in individuals infected with HIV may be involved in the pathogenesis of HIV-related microvasculopathy.

[Cerebral oxygen reactivity determination--a simple test with potential prognostic relevance]

Brain tissue oximetry (ptiO2) using flexible micro-polarographic electrodes is a loco-regional approach to monitor oxygen supply to the injured brain, after neuronal damage. In patients after severe head injury (SHI), disturbances of CBF and CO2 related vasoconstriction have been demonstrated. CO2 reactivity testing may assist to determine outcome in these patients. Not much information is available on the preservation of vasoreactivity to arterial hyperoxia after neuronal damage. Therefore, we studied the response of ptiO2 in 7 piglets and in 14 patients on day one after trauma to 100% FiO2 ventilation (O2rea) and analyzed the 3 month outcome using the Glasgow-Outcome-Score (GOS). In the animal study, we placed a Paratrend 7 (P7) sensor for ptiO2 measurements in the non injured frontal white matter. The animals were anesthetized and mechanically ventilated. FiO2 was increased from 30 (+/- 5)% to 100% over a period of 5 minutes. In patients, we placed the P7 probe in the frontal lobe. FiO2 was increased from 35 (+/- 5)% to 100% over a period of 6 hours. O2rea was tested by calculating the percentage change of ptiO2 during 100% FiO2 ventilation, compared to the baseline value of 35% FiO2. By analyzing the patient outcome, we were able to define two patient populations according to the GOS at three month (Group I: favorable outcome [GOS 0-2]; Group II: poor outcome [GOS 3-4]). For the non-injured brain tissue in animals were revealed an O2rea = 0.21 (+/- 0.12).

PATIENTS

Group I: O2rea = 0.4 (+/- 0.16); Group II: 0.9 (+/- 0.6). Group I and II were statistical significant different (p < 0.05; unpaired t-test). Oxygen reactivity in severely head patients is a simple test with prognostic value using ptiO2 measurement. These results may be explained by the close relationship of CBF disturbances to oxygen vasoreactivity after traumatic brain injury. The O2rea in animals without neuronal damage is smaller than in patients after SHI. We speculate, the animal data could be considered as normal value of O2rea in non injured brain tissue.

Initial and follow-up MR imaging findings in AIDS-related progressive multifocal leukoencephalopathy treated with highly active antiretroviral therapy

BACKGROUND AND PURPOSE

Recent studies have shown the beneficial effect of highly active antiretroviral therapy (HAART) in AIDS-related progressive multifocal leukoencephalopathy (PML). The purpose of our study was to evaluate the initial and follow-up imaging findings and survival in patients with PML who were treated with HAART.

METHODS

The clinical course and MR imaging findings on initial and follow-up MR studies in four consecutive AIDS patients with PML who were treated with HAART are described.

RESULTS

Two patients were short-term survivors and died after 3 months. Two patients are still alive, with a survival time of 22 and 43 months, respectively. On initial MR studies, more extensive white matter changes were seen in the short-term survivors. Development of a mass effect and temporary enhancement (in one patient) was observed in two HAART responders on follow-up MR studies. Increased hypointensity on T1-weighted images with concomitant low signal on fluid-attenuated inversion-recovery fast spin-echo (FLAIR-FSE) images was seen in two responders, representing leukomalacia. Atrophic changes of the involved areas of the brain, consistent with burnt out PML lesions, were seen in two long-term survivors. In the short-term survivors, increased hypointensity was present on T1-weighted images with increased high signal on FLAIR-FSE images, representing progressive destructive disease.

CONCLUSION

Our results suggest that a clinical and radiologic response can be seen in some patients with AIDS-associated PML on HAART while in others there may be no beneficial response. Development of a mass effect and temporary enhancement on MR images in the early phase of treatment might represent positive predictive factors for prolonged survival.

Sex differences in HAART-associated dyslipidaemia

OBJECTIVES

Because female sex protects against dyslipidaemia and atherosclerosis in normal subjects, we aimed to reveal potential sex differences in metabolic side-effects of a newly initiated highly active antiretroviral therapy (HAART) regimen, and to relate these changes to endothelial cell activation as measured by levels of circulating E-selectin (cE-selectin).

DESIGN

Prospective longitudinal cohort study.

SETTING

Tertiary care centre at a University Hospital.

METHODS

HIV-seropositive male (n = 27) and female patients (n = 13) with a plasma viral load of > or = 10 000 copies/ml and 35 healthy controls were enrolled in the study. All participants were weight stable, free of acute opportunistic infections, and had not taken any protease inhibitors before. Serum levels of lipids, insulin, leptin, and cE-selectin were measured before initiation of HAART, and at 3 and 6 months thereafter.

RESULTS

HAART increased serum levels of triglycerides, leptin, and low-density lipoprotein (LDL) cholesterol; these effects were more distinct in women. Fasting insulin levels and the LDL : high density lipoprotein (HDL) ratio increased only in female HIV-infected patients (P < 0.02 versus men). In contrast, endothelial activation, as measured by cE-selectin, decreased more in men (P < 0.02) than in women. As a consequence, women had higher triglycerides and leptin levels after therapy than did men, and the LDL : HDL ratio and cE-selectin levels, which were initially higher in men, were no longer different between the sexes.

CONCLUSIONS

Metabolic adverse effects during HAART are more pronounced in women than in men. Hence, female HIV-infected patients seem to loose part of their natural protection from atherosclerosis during antiretroviral therapy.

Primary central nervous system lymphoma in AIDS: a wider spectrum of CT and MRI findings

Diagnosis of primary central nervous system lymphoma (PCNSL) in patients with AIDS based on radiological findings is still a challenging problem. Our purpose was to review the CT and MRI findings in PCNSL in our patients with AIDS and compare them with those reported in the literature. CT and MRI of 28 patients with AIDS and pathologically confirmed PCNSL were analysed retrospectively for the number of lesions, their site, size, density, signal intensity, contrast enhancement, oedema and mass effect. We found 82 lesions. On CT 45 lesions were found in 22 patients, whereas MRI revealed 66 in 20 patients. The lymphoma was solitary in 20 patients (29 %) and multiple in 20 (71%). Spontaneous haemorrhage was seen in 7 patients. Contrast-enhanced MRI showed no enhancement in 27.3 % (18/66) of the lesions. In one patient diffuse signal abnormalities in the white matter were seen on T2-weighted images. Our findings suggest that the previously described spectrum imaging characteristics of PCNSL has widened. Neuroradiologists should be aware of the variable appearance in patients with AIDS. Spontaneous haemorrhage, a non-enhancing lesion, or diffuse white matter changes do not exclude lymphoma in an immunocompromised patient.

Evaluation of cytomegalovirus retinitis management. Outcome of four years of cytomegalovirus therapy

Cytomegalovirus (CMV) is the most common pathogen of opportunistic viral infections in patients with the acquired immunodeficiency syndrome. In this study, we assessed the therapeutic outcome of our treatment regimen of CMV retinitis by analysing retrospectively 33 consecutive patients. The clinical utility of CMV cultures from blood, urine and throat specimens obtained at the time of diagnosis was additionally evaluated. Treatment started with ganciclovir (GCV) therapy. In case of relapsing retinitis, re-induction therapy was initiated, and if unsuccessful, the patient was switched to foscarnet. Patients developing resistant retinitis despite foscarnet therapy were offered a GCV-foscarnet combination therapy. Under primary GCV therapy, the median first stable interval of the whole group was 202 days (mean 238 days). Twenty-five out of 33 CMV retinitis patients (76%) responded to initial GCV therapy. Eleven of these patients showed relapsing retinitis that could be stabilised in 3 patients solely with combination therapy. Eight patients did not respond to primary GCV therapy. Three of them improved with foscarnet, but 3 patients did not respond to either treatment. In 18 (56%) out of 32 patients, CMV cultures yielded positive results. Considering our series, we may conclude that in the majority of patients primary or secondary viral resistance can be overcome by dose increase, switching to the alternative drug or a combination therapy.

Endoscopic third ventriculostomy is the treatment of choice for obstructive hydrocephalus due to pediatric pineal tumors

Pineal lesions in the pediatric patient are often complicated by the development of hydrocephalus due to obstruction of the aqueduct or the third ventricle by tumor masses. In such cases, hydrocephalus treatment has the highest priority and should be performed prior to any surgical treatment of the pineal tumor itself. The golden standard in obstructive hydrocephalus treatment remains placement of a temporary or permanent cerebrospinal fluid shunt, although there are many long-term complications associated with a shunt system. To avoid these and to render the patients independent from a failure-prone shunt system, we employed endoscopic third ventriculostomy for permanent relief of elevated intracranial pressure prior to surgical removal of the pineal lesions. The present study summarizes the results of this approach in 7 pediatric patients with obstructive hydrocephalus. No complications of the endoscopic procedure were encountered, and the ventriculostomy remained patent in all cases, as confirmed by motion sensitive MRI. The advantages of endoscopic third ventriculostomy as compared with other techniques are discussed, and its increasing role in the management of children with space occupying lesions of the pineal region is defined.

Highly active antiretroviral therapy for patients with AIDS dementia complex: effect on MR imaging findings and clinical course

BACKGROUND AND PURPOSE

Recent studies have reported the clinical improvement in patients with AIDS treated with a combination of antiretroviral regimens. The purpose of our study was to describe the effects of highly active antiretroviral therapy on MR images in patients with HIV encephalopathy and to compare the clinical course with follow-up neuroimaging studies.

METHODS

Initial and follow-up MR imaging findings are described in four patients with AIDS dementia complex at baseline and after antiretroviral therapy, and correlated with clinical and immunologic findings.

RESULTS

Initial MR imaging revealed white matter signal abnormalities on long-TR images without mass effect and without enhancement on postcontrast images, consistent with HIV encephalopathy. Lesions were located in the basal ganglia and posterior fossa in two patients. All four patients showed progression of white matter disease on the first follow-up MR scan (mean, 6 months). On subsequent scans, regression was seen in three patients and stabilization of white matter disease was observed in one patient. Increases in CD4+ count and decreases in viral load below the limit of quantification were present in all patients.

CONCLUSION

Although our patient population was small, the results suggest that disease regression in patients with AIDS dementia complex after treatment with highly active antiretroviral therapy can be characterized and monitored by MR imaging.

Cerebrovenous blood temperature-influence of cerebral perfusion pressure changes and hyperventilation: evaluation in a porcine study and in man

The objective of the first part of this study was to use an animal model to investigate the relationship between temperature in the cerebrovenous compartment and cerebral perfusion pressure. In the second part of the study, the objective was to examine the influence of hyperventilation and hypothermia on jugular bulb temperature and body temperature in patients undergoing elective neurosurgery. Intracranial pressure was increased artificially by inflating an infratentorial supracerebellar placed balloon catheter in nine pigs under general anesthesia. Temperature was monitored by thermocouples inserted in the sagittal sinus, white matter of the left lobe and abdominal aorta during the ensuing decrease in cerebral profusion pressure (CPP). Cerebrovenous blood temperature (jugular bulb) and body temperature (urinary bladder) were simultaneously monitored in 24 patients undergoing craniotomy. Moderate hyperventilation was performed in all patients. Cerebrovenous blood and core body temperature were recorded and differences between these two temperatures calculated at the beginning and the end of hyperventilation. At the beginning of the intracranial pressure (ICP), increase mean temperatures of cerebrovenous blood and cerebral tissue (left lobe) were lower than core body temperature. During CPP reduction the difference between core body temperature and cerebrovenous blood temperature increased significantly from 0.86+/-0.44 degrees C prior to ICP rise to 1.19+/-0.58 degrees C at maximum ICP. Before hyperventilation, cerebrovenous blood temperature was higher in 19 patients (+/- difference: 0.34 degrees C +/- 0.27) and equal or lower in five patients (difference: -0.08 degrees C +/- 0.11), than core body temperature. At the end of hyperventilation, the difference between cerebrovenous blood temperature and core body temperature increased (+0.42 degrees C +/- 0.24) in those 19 patients who had started with a higher cerebrovenous blood temperature and decreased (-0.10 degrees C +/- 0. 18) in the other five patients. Both studies demonstrated that the temperature of cerebrovenous blood is influenced by maneuvers which are supposed to decrease cerebral blood flow.

High dose intravenous immunoglobulin (IVIG) in dermatomyositis: clinical responses and effect on sIL-2R levels

An open study was conducted to identify and investigate dermatomyositis patients who benefit from IVIG treatment, based on dermatological criteria, myositis-related symptoms and immune/inflammatory parameters. 19 patients (16 females and three males, ages 31-84) suffered from dermatomyositis, and 4/19 patients had paraneoplastic dermatomyositis. We monitored the disease activity by documenting the clinical symptoms, recording muscle-related parameters (electromyography, serum creatine kinase, histopathology), and by determining circulating autoantibodies and serum levels of IL-6, sIL-2R, sTNF-a-R, sICAM-1, and sCD8. 7/19 patients responded to IVIG. They had severe skin but only moderate muscle involvement, no autoantibodies, and no malignancy. IVIG-nonresponders had severe skin and muscle disease, concomitant with autoantibodies and/or malignancy. sIL-2R levels were initially elevated in all patients but reverted to normal in IVIG-responders only. Creatine kinase-levels and other parameters did not correlate with disease activity and/or treatment response. IVIG is effective in selected dermatomyositis patients. sIL-2R serum levels appear to be useful predictors of IVIG-induced treatment response and disease activity.

[Is the laryngeal mask a minimally invasive instrument for securing the airway? Supplementary remarks on the paper "Injures and dangers in the use of the laryngeal mask" by V. Hempel, Anaesthesist (1999)48:399-402]

Minor laryngopharyngeal complaints following anaesthesia considerably determine postoperative patient comfort. They cannot be eliminated but reduced by experience and careful preparation and insertion technique. The incidence of minor laryngopharyngeal symptoms following the use of the laryngeal mask airway is similar to that following endotracheal intubation. However, there seems to be a distinct pattern of complaints: discomfort with swallowing is more frequent after LMA, whereas dysphonia is more often observed following endotracheal intubation. The significance of LMA cuff pressures in the pathogenesis of postoperative throat complaints remains unclear. There is sound evidence that cuff pressure is not a representative measure for the effective pressure load upon the pharyngeal mucosa. Measurement of cuff pressure is not obligatory, instead reduction of cuff volume to a "just seal" situation seems to be a reasonable approach. The laryngeal mask airway has definitely changed anaesthesiology airway management. Whether this is due to its supposedly less invasiveness compared to endotracheal intubation has not been proven by scientific investigations.

Is it useful to measure supratentorial ICP in the presence of a posterior fossa lesion? Absence of transtentorial pressure gradients in an animal model

Previous studies with animal models of supratentorial ICP elevation have demonstrated a pressure gradient between the supratentorial and the infratentorial compartments. The present study was designed to investigate the possible presence of such a gradient in the case of infratentorial ICP elevation. An inflatable infratentorial balloon catheter was implanted in seven domestic pigs. The infratentorial ICP (ICPi) was measured in the left cerebellar hemisphere, and the supratentorial ICP (ICPs) was measured in the left cerebral hemisphere. The corresponding pulse amplitudes (ICPi-PA, ICPs-PA) were recorded in both compartments, and the cerebral perfusion pressure (CPP) was calculated. ICPi and ICPs values prior to balloon inflation were 4.4 (SD 2.2) and 4.1 (SD 2.3) mm Hg, respectively, and increased to 63.1 (SD 32.6) and 62.3 (SD 28.1) mmHg after balloon inflation. ICPi-PA rose from 3.1 (SD 0.43) to 12.8 (SD 8.0) mmHg, and ICPs-PA rose from 3.2 (SD 0.63) to 13.0 (SD 7.1) mmHg. CPP decreased from 86.1 (SD 12.0) to 55.4 (SD 14.6) mm Hg. The paired difference between ICPi and ICPs values was 0.44 (SD 1.96) mmHg, and the paired difference of ICP amplitudes was 0.03 (SD 1.19) mmHg. All these differences in infratentorial and supratentorial values were statistically not significant. In conclusion, infratentorial ICP elevation in the presented pig model leads to a uniform ICP elevation in the intracranial space without development of a considerable pressure gradient below and above the tentorium. In the low pressure part of the ICP curve, cerebrospinal fluid connects the compartments and contributes to the pressure equilibrium. The early obstruction of the foramen magnum by intruding cerebellar tissue seems to isolate the infratentorial from the spinal compartment. In the high-pressure part of the curve, the upwards cerebellar transtentorial herniation takes over the pressure transfer, and the whole intracranial space can be considered as a single compartment in the pig.

Infection of circulating CD34+ cells by HHV-8 in patients with Kaposi's sarcoma

Human herpesvirus type 8 (HHV-8) has been identified as the most likely candidate to be involved in the development of Kaposi's Sarcoma (KS). HHV-8 has been associated with all forms of KS, primary effusion lymphoma, and multicentric Castleman's disease and detected in various non-neoplastic cells. Its presence in cells of the different hemopoietic lineages has not yet been investigated in a comprehensive and systematic manner. In this study we searched for the presence of HHV-8 in different subpopulations of peripheral blood mononuclear cells (PBMC) from patients with classic and AIDS-associated KS, as well as from HIV-1 sero-positive and sero-negative persons without KS. Thirty-four samples of PBMC were isolated from 30 patients. Subpopulations were isolated with immunomagnetic beads. Polymerase chain reaction for HHV-8 DNA was performed on PBMC and subpopulations with a primer pair selected from ORF26 of the viral genome. Polymerase chain reaction products were subsequently Southern blotted and hybridized. In patients with KS, HHV-8 DNA was detected in nine of 11 (81%) CD19+ cells, four of 11 (36%) CD2+ cells, three of 11 (27%) CD14+ cells, and nine of 11 (81%) of the remaining depleted cell populations (DP) that contain CD34 positive cells. In a subsequent set of experiments HHV-8 DNA was detected in 10 of 12 (83%) CD34 positive cell fractions. All cell subpopulations from the non-KS group were HHV-8 negative, with the exception of one positive B cell sample obtained from an HIV-infected patient. Our data demonstrate that in peripheral blood HHV-8 is detectable not only in CD19+ cells, as previously reported, but also in other cells, including T cells, monocytes, and cells devoid of specific lineage markers. We also show for the first time that CD34+ cells in peripheral blood of KS patients are a predominant HHV-8-harboring population, suggesting that they represent an additional important reservoir for this virus in vivo.

A case of HIV-associated cerebral histoplasmosis successfully treated with fluconazole

Clinically apparent involvement of the central nervous system is a rare event in cases of disseminated histoplasmosis, even in HIV-infected persons. Despite therapy with amphotericin B, mortality remains very high. Reported here is the case of an HIV-infected patient with a 3-month history of fever, cough, weight loss and miliary lung infiltrates. Four weeks after initiation of tuberculostatic therapy, high-grade fever, neurological symptoms, personality changes and respiratory deterioration occurred. Magnetic resonance imaging of the brain showed multiple mass lesions, and a chest radiograph revealed worsening of pulmonary infiltrates. Methenamine silver staining of a lung biopsy specimen demonstrated Histoplasma capsulatum. Subsequently, this pathogen was cultured from lavage fluid. Following high-dose intravenous fluconazole therapy (800 mg once daily), the patient's condition improved markedly within 10 days, followed by an almost complete resolution of pulmonary and cerebral mass lesions. This is believed to be the first documented case of rapid improvement of disseminated histoplasmosis with central nervous system involvement in an HIV-infected patient upon induction of therapy with fluconazole.

Control of cytomegalovirus retinitis after combination antiretroviral therapy

PURPOSE

To report on AIDS patients having combination antiretroviral therapy whose cytomegalovirus (CMV) retinitis remained inactive after discontinuation of anti-CMV maintenance therapy.

METHODS

We describe the course of CMV-retinitis in 3 patients with AIDS after initiation of combination antiretroviral therapy.

RESULTS

After cessation of anti-CMV therapy no relapse of CMV-retinitis has been observed for up to 18 months. Two of the patients developed new CMV-retinitis in the first months after initiation of combination therapy, nevertheless after further improvement of immunological parameters retinitis remained stable without anti-CMV therapy.

CONCLUSION

The sustained immunological effects of combination therapy are possibly sufficient enough to provide protection against CMV-retinitis.

[Antiretroviral drugs 1998/1999]

Combination antiretroviral therapy has proven to be the most effective approach to treat HIV disease. The primary goal of treatment for HIV infection is to achieve maximal and durable suppression of viral replication. After decrease of viral load numerical and functional recovery of the immune system is observed and has been associated with better clinical performance of patients. The number of antiretroviral drugs has increased over the last years and currently 12 compounds are available. Wise combinatorial use of these drugs, extensive information and long-term motivation of patients, regular and correct intake are a prerequisition rather than a guarantee of therapy success. These drugs exhibit several class- and substance-specific short-/long-term toxicities, complex pattern of cross-resistance and drug-drug interactions and therefore in depth knowledge of the pharmacology of antiretroviral drugs is mandatory for primary care providers.

Mycobacteria other than tuberculosis with an emphasis on Mycobacterium xenopi in clinical specimens from AIDS patients at the University Hospital of Vienna from 1989 to 1996

This study was carried out to provide an overview of the frequency of various mycobacterial species isolated from AIDS patients at the University Hospital of Vienna from 1989 to 1996. Mycobacterium xenopi was found to be the second most common nontuberculous mycobacterial species (92 specimens from 30 patients) and was cultured predominantly from respiratory tract specimens. In 55% of patients, chest X-rays taken at the time of isolation demonstrated pathologic changes which could not be attributed to another cause. Therefore, according to our results, Mycobacterium xenopi should be viewed as an infectious agent rather than a contaminant in AIDS patients.

[Radiologic aspects of infarction of the appendix epiploica]

Clinical, US, CT and MR findings were reviewed in 5 patients with primary epiploic appendagitis (3 men, 2 women, mean age 38 years, age range 29-62 years) seen between December 1994 and December 1997. Diagnosis was reached in all cases with CT, with US in 3 and with MR in 1. Follow-up CT was performed in 2 cases and clinical follow-up in 4. One patient underwent surgery. Initial US, CT or MR examinations revealed a fatty oval-shaped nodule located anteriorly or anterolaterally to the left colon. The greater diameter ranged from 20 to 30 mm. Perinodular lesions with strands of periappendicular fat and thickened parietal peritoneum were visualized in all cases without any other inflammatory process in the abdomen. Symptoms resolved within 4 days in all patients. Signs of fatty inflammatory processes resolved in the 2 patients who had follow-up CTs. Primary epiploic appendagitis has characteristic US, CT and MR features which help guide medical treatment.

Simultaneous continuous measurement of pO2, pCO2, pH and temperature in brain tissue and sagittal sinus in a porcine model

INTRODUCTION

The clinical use of brain tissue oxygen measurement in patients with severe head injury is increasing. It is important to compare the findings in brain tissue with cerebrovenous blood oximetry, to obtain normal values and to find out limitations of the method. We evaluated a newly available multisensor probe simultaneously in the brain tissue and in the sagittal sinus in a porcine animal model.

METHODS

We placed the Paratrend 7-probe (BSL, High Wycombe, UK) in the left frontoparietal white matter and measured pO2 (PtiO2), pCO2 (ptiCO2), pH and temperature while simultaneously measuring these parameters (pcvO2, pcvCO2) in the sagittal sinus in 7 pigs under general anaesthesia during oxygen enhancement.

RESULTS

The relation between oxygen increase in brain tissue and in the sagittal sinus showed a coefficient of correlation (CCmean) rmean = 0.96. The quantitative response in brain tissue was much more sensitive than in the sinus. A close correlation between pCO2 in brain tissue and sagittal sinus and the increase of the inspired oxygen was seen: CC ptiCO2 to arterial oxygen pressure (paO2) - rmean = 0.67, CC pcvCO2 to paO2 - rmean = 0.88.

CONCLUSIONS

Measuring partial oxygen pressure in brain tissue is more responsive to physiological variations, and the absolute values are more sensitive than oxygen measurement in the cerebrovenous compartment. This is important for interpreting measured values and introducing new coefficients for patient monitoring.

Temperature of the cerebrovenous blood in a model of increased intracranial pressure

Hypothermia has a considerable protective effect during brain ischemia. On the other hand small increases of brain temperature have a remarkable effect on the exacerbation of neurological damage following an ischemic event. Hyperthermia of the brain tissue after severe head injury is described. The effect of acutely increased intracranial pressure on cerebrovenous blood temperature is not described yet. The aim of this study was to investigate the relationship between temperature in the cerebrovenous compartment (Tcv) and changes of the CPP in an animal model of raised intracranial pressure.

METHODS

A thermocouple was inserted in the sagittal sinus in 9 pigs under general anesthesia. By stepwise inflating a supracerebral and infratentorial placed balloon catheter intracranial pressure (ICP) was increased and CPP concomitantly decreased. The central body temperature was measured simultaneously in the abdominal aorta (Ta) with a second thermocouple.

RESULTS

In our model th Tcv was lower than Ta at the beginning of the ICP increase. The mean difference between Ta and Tcv, (delta Ta-cv) was 0.86 degree C (+/- 0.44) prior to ICP increase and 1.19 degrees C (0.58) at the maximum ICP increase. Thus, delta Tav increased during CPP reduction. This relation was represented by an adjusted R(square) of r2 = 0.89 (p < 0.001).

CONCLUSIONS

The CPP decrease, caused by an increasing ICP, results in changes of the cerebrovenous blood temperature. Interpreting the present results the experimental situation of a relative colder cerebral compartment in comparison to the central body temperature has to be considered. However, the results imply, that simultaneous temperature monitoring of the central body temperature and the cerebrovenous blood temperature is an additional source of information about relative changes of the CBF.

Comparison between continuous brain tissue pO2, pCO2, pH, and temperature and simultaneous cerebrovenous measurement using a multisensor probe in a porcine intracranial pressure model

Local brain tissue oxygenation (p(ti)O2) and global cerebrovenous hemoglobin saturation (SjO2) are increasingly used to continuously monitor patients after severe head injury (SHI). In patients, simultaneous local and global oxygen measurements of these types have shown different results regarding the comparability of the findings during changes in CPP and ICP. This is in contrast to theoretical expectations. The aim of this study was to compare p(ti)O2 measurement with cerebrovenous oxygen partial pressure measurement (p(cv)O2) in an animal intracranial pressure model. To this end, a multisensor probe was placed in the left frontoparietal white matter to measure p(ti)O2, pCO2 (p(ti)CO2), pH (pH[ti]), and temperature (t[ti]) while simultaneously measuring these same parameters (p(cv)O2, p(cv)CO2 pH(cv), t[cv]) in the sagittal sinus of 9 pigs under general anesthesia. By stepwise inflating a balloon catheter, placed in supracerebellar infratentorial compartment, ICP was increased and CPP was decreased. The baseline levels of p(ti)O2, p(ti)CO2, and pH(ti) in the noninjured brain tissue showed more heterogeneity compared to the findings in cerebrovenous blood. Both, p(ti)O2 and p(cv)O2 were significantly correlated to the induced CPP decrease. PCO2 was inversely correlated to the course of CPP in both measurement compartments. Temperature measurement showed a positive correlation with CPP in both compartments. These findings demonstrate that brain tissue oximetry and cerebrovenous PO2 measurement are sensitive to CPP changes. The newly available continuous parameters in multisensor probes could be helpful in interpreting findings of cerebral oxygen measurement in man by analyzing the interrelationship of these parameters.

Genus level identification of mycobacteria from clinical specimens by using an easy-to-handle Mycobacterium-specific PCR assay

An easy-to-handle Mycobacterium-specific PCR assay for detection of the presence of a wide range of mycobacterial species in clinical samples was evaluated. The performance of the genus probe was compared with the performance of probes specific for Mycobacterium tuberculosis and Mycobacterium avium and with that of standard culture. In addition, the utility of an internal control in monitoring amplification inhibitors was studied. Of 545 respiratory and 325 nonrespiratory specimens (a total of 870 specimens), 58 (6.7%) showed the presence of amplification inhibitors, as determined by a negative result for the internal control. Of these 58 specimens, 31 (53%) were stool specimens; other material, even citrate blood after lysis of erythrocytes, did not pose a problem with regard to inhibition of PCR amplification. Eighty-one of the remaining 812 specimens had a positive Mycobacterium culture result. Of these culture-positive specimens, 58 (71.6%) showed a positive result with the Mycobacterium genus-specific probe. Seventy-two samples had a positive result with the Mycobacterium-specific probe but a negative culture result. Of these 72 samples, 26 samples were regarded as true positive, either because the M. tuberculosis- or M. avium-specific probe was also positive at the same time or because other specimens from the same patient taken at the same time were culture positive. The sensitivity of the Mycobacterium-specific probe was 78.5% and the specificity was 93.5%. This study showed that pretesting of clinical specimens for mycobacteria to the genus level with a Mycobacterium-specific probe offers the routine clinical laboratory the possibility of detecting tuberculous and nontuberculous mycobacteria with one test. Furthermore, specimens testing positive with the genus-specific probe can be immediately identified with species-specific probes.

Continuous pO2 and pCO2 measurement in brain tissue and cerebrovenous blood during different inspired oxygen settings. A porcine model

The clinical use of brain tissue oxygen measurement in patients with severe head injury is increasing. It is important to compare the findings in brain tissue with jugular bulb oximetry, to obtain normal values and to find out limitations of the method. We evaluated a newly available multisensor probe simultaneously in the brain tissue and in the sagittal sinus in a porcine animal model. We placed the Paratrend 7-probe (BSL, High Wycombe, UK) in the left frontoparietal white matter and measured pO2 (ptiO2), pCO2 (pti CO2), pH and temperature while simultaneously measuring these parameters (pcvO2, pcvCO2) in the sagittal sinus in 7 pigs under general anaesthesia during a 100% oxygen enhancement. The relation between oxygen increase in brain tissue and in the sagittal sinus showed a coefficient of correlation (CCmean) r(mean) = 0.96. The quantitative response in brain tissue was much more sensitive than in the sinus. A close correlation between pCO2 in brain tissue and sagittal sinus and the increase of the inspired oxygen was seen: CC ptiCO2 to arterial oxygen pressure (paO2) - r(mean) = 0.67, CC pcvCO2 to paO2 - r(mean) = 0.88. This is important for interpreting measured values and introducing new coefficients for patient monitoring. Newly available continuous brain oxygen measurement methods will allow better understanding of brain metabolism in the future.

Comparison between continuous brain tissue measurement and cerebrovenous measurement of pO2, pCO2 and pH in a porcine intracranial pressure model

Simultaneous oxygen measurements in brain tissue (p(ti)O2) and hemoglobin saturation measurement in cerebrovenous blood in patients after severe head injury have shown different results regarding the comparability of the findings in respect to CPP and ICP. This is contrast to theoretical expectations. The aim of this study was to compare continuous ptiO2 measurement with oxygen partial pressure measurement in sagittal sinus (pO2cv) during simultaneously performance in an animal intracranial pressure model. For continuous measurement we used a newly available multisensor probe. We placed a Paratrend 7 probe (BSL, High Wycombe, UK) in the left frontoparietal white matter and measured ptiO2, pCO2 (ptiCO2) pH (pHti) and temperature (t(ti)) while simultaneously measuring these parameters (pcvO2, pcvCO2, pHcv, tcv) in the sagittal sinus in 9 pigs under general anaesthesia. A fogarty balloon catheter was placed supracerebellar infratentorial and inflated stepwise in order to increase ICP. The baseline levels of pO2ti, pCO2ti und pHti in the non-injured brain tissue showed a more extended heterogeneity compared to the findings in cerebrovenous blood. Both, pO2ti and pO2cv were significant correlated to the CPP decrease. In both measurement compartments pCO2 was inverse correlated to the course of CPP and seems the course of pH mainly to determine. p(ti)O2 as well as p(cv)O2 showed a close correlation to the CPP course and have proven to be qualified to indicate metabolic information about the relation of cerebral blood flow and metabolic cerebral demands. The measurement of CO2 tension in both measurement compartments shows a distinct heterogeneity of the absolute values and the results are only weak correlated to CPP. Metabolic influence on this parameter could not be revealed in the used experimental approach.

Dorsal spondylodesis of unstable thoracolumbar fractures by a far-lateral approach to the disc

This paper describes a modified and less traumatic approach to the thoracolumbar spine and compares it with standard techniques for instrumented spinal fusion. Ten patients with unstable fractures of the thoracolumbar spine were included in the open prospective investigation, and were treated by a surgical technique consisting of a dorsolateral approach to the injured segment, filling the disk space and the fractured vertebra with autologous bone, and transpedicular fixation with an AO internal fixator. All patients were followed for 6 to 12 months after surgery by clinical tests and spinal X-rays. Excellent short-term and long-term results were obtained. A stable bony fusion was achieved in all cases, and a minimal mean decrease of 2 degrees in the kyphosis angle was found at late follow-up. No major complications related to the procedure were encountered, and no worsening of neurological deficits occurred after surgery. In conclusion, the far-lateral approach to the thoracolumbar spine yields results which are equivalent or better than those of standard techniques. Major advantages of our procedure, as evaluated in this rather small group of patients, are selective immobilization of the injured segment without involvement of functionally intact spinal levels, no manipulations within the spinal canal boundaries, and relatively limited exposure of the spine.

Comparison of T2-weighted and fluid-attenuated inversion-recovery fast spin-echo MR sequences in intracerebral AIDS-associated disease

PURPOSE

To compare the value of fast fluid-attenuated inversion-recovery (FLAIR) with T2-weighted fast spin-echo MR imaging in the detection of acquired immunodeficiency virus (AIDS)-related lesions of the brain.

METHODS

Forty-four human immunodeficiency virus (HIV)-positive patients were examined with both sequences on either a 1.0-T or a 1.5-T MR system. The number, size, location, and conspicuity of the lesions were evaluated by two independent observers. Contrast ratios between lesions and normal brain/cerebrospinal fluid were determined, and contrast-to-noise ratios were calculated.

RESULTS

FLAIR was found to be superior to T2-weighted fast spin-echo in detection of small lesions and of lesions located in cortical/subcortical regions and deep white matter. The two techniques were equal in delineation of lesions larger than 2 cm and for lesions located in the basal ganglia and posterior fossa. In 24 patients, more lesions were detected with the FLAIR fast spin-echo technique. Lesion/cerebrospinal fluid contrast ratios and contrast-to-noise ratios were significantly higher for the FLAIR fast spin-echo sequences than for the T2-weighted fast spin-echo sequences.

CONCLUSION

FLAIR allows early detection of small lesions in subcortical and cortical locations, especially in HIV encephalitis. Because of its improved lesion detection rate and greater overall lesion conspicuity, we believe FLAIR is useful in the evaluation of subtle changes in the brains of AIDS patients with central nervous system disease, and could even replace the T2-weighted fast spin-echo technique.

Factors predicting pituitary adenoma invasiveness in acromegalic patients

Forty-four adult acromegalic patients carrying growth hormone-producing pituitary macroadenomas were investigated with neuroradiological and endocrinological techniques. Plasma growth hormone and somatomedin-C levels were repeatedly measured before surgical removal of tumors and during the follow-up period. Twenty-five patients presented preoperatively with an invasive adenoma that involved the cavernous sinus (CS). Diagnosis of tumor invasivity was made according to distinct neuroradiological criteria and was confirmed or rejected during surgery Significantly higher basal growth hormone levels were found in patients with CS invasion than in cases without tumor growth in the CS. Evidence is presented that plasma growth hormone level in acromegalics is a more sensitive indicator for predicting tumor invasiveness than somatomedin-C. Growth hormone basal values before surgery and the extent of their decrease after removal of tumor correlate with adenoma growth in the parasellar compartments and should be used as a prognostic factor to aid in planing adjuvant tumor treatment.

Continuous monitoring of the partial pressure of oxygen in cerebral venous blood

OBJECTIVE

Clinical oxygen monitoring in the injured brain is somewhat difficult. However, ischemia is one of the major factors responsible for secondary tissue damage after head injury or subarachnoid hemorrhage. Therefore, the aim of the present study was to investigate the value of continuously monitoring the partial pressure of oxygen in cerebral venous blood (PcvO2) during changes in intracranial pressure (ICP).

METHODS

In eight domestic pigs with Clark type probes placed in the posterior third of the superior sagittal sinus, PcvO2 was continuously registered while ICP was stepwise elevated by an inflatable balloon placed below the tentorium. Arterial blood pressure was continuously monitored, cerebral perfusion pressure (CPP) was calculated, and arterial partial carbon dioxide pressure and partial pressure of oxygen were registered intermittently.

RESULTS

The mean intraparenchymal ICP before the start of balloon inflation was 5 +/- 1 mm Hg, the mean CPP was 80 +/- 15 mm Hg, and the mean PcvO2 was 36 +/- 3 mm Hg. At maximum ICP elevation, CPP decreased to 20 +/- 12 mm Hg, PcvO2 decreased to 10 +/- 6 mm Hg, and ICP increased to 90 +/- 10 mm Hg. Strong linear correlations between ICP and PcvO2 and between CPP and PcvO2 were revealed, and mean correlation coefficients of 0.89 for ICP/PcvO2 and 0.73 for CPP/PcvO2 were calculated.

CONCLUSION

The present study demonstrates that polarographic PcvO2 monitoring in the superior sagittal sinus is a reliable method for the early detection of reduced CPP during ICP elevation. This technique is capable of registering the global oxygen supply and oxygen consumption of the brain. It seems superior to jugular venous oxymetry and is better suited for clinical use because of a somewhat low artifact susceptibility.

Intracuff pressures do not predict laryngopharyngeal discomfort after use of the laryngeal mask airway

BACKGROUND

The laryngeal mask airway (LMA) is a large foreign body that exerts pressure on the pharyngeal mucosa, which may lead to throat discomfort. To determine whether intracuff pressures are associated with such discomfort, a randomized, double-blind study was performed to determine the effect of high versus low intracuff pressures.

METHODS

Seventy healthy women were randomly allocated to two groups with different LMA intracuff pressures: 30 mmHg (low pressure) or 180 mmHg (high pressure). Pressures were controlled with a microprocessor-controlled monitor. Insertion of the LMA was performed by one investigator and facilitated with propofol and verified fiberoptically. Anesthesia was maintained with enflurane and nitrous oxide. The LMAs were removed while the patients were still asleep. Patients assessed their laryngopharyngeal complaints (sore throat, dysphagia, hoarseness) at 8, 24, and 48 h after operation on a 101-point numerical rating scale.

RESULTS

No significant difference was found in the overall incidence of complaints between both groups (low pressure: 50%; high pressure: 42%). On the day of surgery, dysphagia (38%) was more frequent than sore throat (16%) or hoarseness (6%) (P < 0.05) within the high-pressure group. In the low-pressure group, the incidence of these complaints was not significantly different (33%, 20%, and 23%, respectively). On the following day, dysphagia was still present in 20% of the women in both groups, and other symptoms comprised 10% or less of the reported complaints.

CONCLUSIONS

Differences in LMA intracuff pressures did not influence either the incidence or severity of laryngopharyngeal complaints.

[Continuous measurement of jugular venous blood gas. A case of subarachnoid bleeding]

INTRODUCTION

Recently, a compact multisensor device 0.5 mm in diameter has become available with a miniaturised Clark electrode for measuring blood oxygen tension and two optical fibres for measuring CO2 tension, pH, and temperature (Paratrend 7, Biomedical Sensors, High Wycombe, UK). We used this new probe for continuous blood gas monitoring in the jugular bulb as an alternative to the commonly used fiberoptic spectrophotometric oximetric measurement of haemoglobin saturation.

RESULTS

A 64-year-old patient was admitted for surgery of a right-sided intracranial aneurysm. During surgery, with no artefacts or evidence of catheter drift, a normal jugular venous pO2 (pjvO2) of 39 +/- 3 mmHg was measured. Over the period of weaning, two declines in pjvO2 occurred (22.5 and 18.7 mm Hg) associated with a decline in CO2 tension and a rise in pH. We treated these events successfully by analgosedation, controlled ventilation with an inspired oxygen fraction of 70%, and elevation of the mean arterial blood pressure to over 100 mmHg. Extubation was possible about 24 h later. Furthermore, 3 h after extubation pjvO2 values could be monitored without difficulty despite movement of the patient.

DISCUSSION

The technique of polarographically measuring pjvO2 with a Clark-type probe appears superior to fibreoptic jugular venous oximetry due to the clearly lower incidence of faulty measurements, especially in the intensive care unit, where patients undergo frequent nursing interventions and tend to awaken. We did not even observe artefacts due to patient movement after extubation. A limitation of the new multisensor system might be the distance of 4 cm between the sensor tip and the end of the insertion catheter, which makes samples drawn for in vitro blood gas analyses to control the continuous monitoring less comparable. Improvements in the construction of the probe are recommended.

Laryngo-pharyngeal complaints following laryngeal mask airway and endotracheal intubation

STUDY OBJECTIVE

To investigate the incidence and severity of laryngo-pharyngeal complaints following anesthesia with the use of a laryngeal mask airway (LMA) compared with endotracheal intubation in adults.

DESIGN

Prospective study with randomized patient selection.

SETTING

University medical center.

PATIENTS

202 adult ASA physical status I, II, and III patients scheduled for elective surgery of either an extremity or breast, or a transurethral resection.

INTERVENTIONS

Following intravenous induction of anesthesia, a standard LMA size #3, #4, or #5 corresponding to the patient's body weight, was inserted in 103 patients; 99 patients were intubated with a polyvinylchloride endotracheal tube [7.5 mm inner diameter (ID) in women and 8.0 mm ID in men]. Cuff pressures in the LMA group were initially reduced to a minimum pressure at which an air-tight seal between the LMA and the laryngeal inlet was provided at a positive pressure of 20 cm H2O during manual bag ventilation. Cuffs of endotracheal tubes were inflated and controlled to a volume needed to prevent gas leak at 35 cm H2O pressure.

MEASUREMENTS AND MAIN RESULTS

Cuff pressures were continuously monitored in both groups. Patients assessed their laryngo-pharyngeal complaints on a 101-point numerical rating scale on the evening after surgery and the following two days. No difference was found in the incidence and severity of sore throat on the evening following surgery or on the two following days. Dysphonia was more frequent following intubation than following LMA insertion on the day of surgery (46.8% vs. 25.3%) and on the first postoperative day (28.1% vs. 11.6%) (p < 0.05). However, the incidence of dysphonia increased with the duration of anesthesia in LMA patients but not in intubated patients. The incidence of dysphagia was significantly higher following LMA insertion compared with endotracheal intubation on the day of surgery (23.8% vs. 12.5%), and on the first postoperative day (22.3% vs. 10.4%). The severity of the individual complaints of minor laryngo-pharyngeal morbidity was comparable between groups. The type of airway management during anesthesia did not affect patient satisfaction with the anesthesia received.

CONCLUSIONS

There is a distinct pattern of laryngo-pharyngeal complaints following the use of the LMA and endotracheal intubation. With regard to minor laryngo-pharyngeal morbidity, the advantage of the LMA to endotracheal intubation is questionable.

[Cerebrovascular fiberoptic catheter oximetry in an intracranial pressure model in swine. New aspects of a clinical routine]

The reliability of continuous fibreoptic oximetry in cerebral venous blood and its correlation with intracranial and cerebral perfusion pressures (pressure-volume curve) were examined in an experimental porcine study.

METHODS

The pressure in the infratentorial compartment of 13 domestic pigs (18-24 kg) was gradually increased by inflating a Fogarty balloon catheter placed on the surface of the right cerebellar hemisphere and below the tentorium. Single volumes of 0.4 ml saline were injected into the inflatable balloon at 1-min intervals up to a total volume of 7 ml. Intracranial pressure (ICP), arterial blood pressure, cerebral perfusion pressure (CPP), and cerebral venous saturation measured continuously by fibreoptic oximetry and intermittent blood-gas analyses (SjO2 superior sagittal sinus) were monitored during balloon inflation. All data were down-loaded onto a PC and evaluated off-line by a commercial statistical software package.

RESULTS

Over the whole pressure-volume curve, two phases of SjO2 behaviour were registered by continuous fibreoptic oximetry (Oximetrix 3, Abbott) (Fig. 1). CPP ranges of less than 50% reduction from the initial value showed a linear correlation (rmittl. = 0.712, P < 0.01) between both parameters (CPP-SjO2). In CPP ranges below a crucial point of about 50 mmHg no such correlation was found (rmittl = 0.176, P < 0.5). In contrast, in 3 pigs a very good correlation was found between CPP and SjO2 over the whole pressure-volume curve as measured by blood-gas analyses of samples from the cerebrovenous catheter (rmittl. = 0.84, P < 0.05).

DISCUSSION

We conclude that in physiological CPP ranges down to 50 mmHg, SjO2 measurement is a reliable method of detecting oxygen desaturation in cerebrovenous blood. Below that CPP value, the fibreoptic catheter showed repeated false-high oxygen saturation values. The accuracy of SjO2 measurement seems to depend on sufficient cerebral blood flow (CBF): with decreasing CBF the amount of cerebral venous outflow is diminished. We believe this is why we could not find a correlation in low CPP ranges with the oximetry catheter. This flow-dependency is a new aspect of fibreoptic cerebrovenous oximetry. The authors recommend that rising SjO2 values after desaturation events be confirmed by blood-gas analyses.

Somatostatin receptor scintigraphy in patients with pituitary adenoma

Presence of high-affinity somatostatin (SST) receptors in most endocrine tumor cells allow in vivo scintigraphic visualization of these neoplasms after intravenous administration of a radionuclide-labeled somatostatin analog. 111In-octreotide is at present the most often used substance for imaging of the SST receptor expression in vivo. The aim of this study is to investigate the correlation between presence of in vivo scintigraphically detectable SST receptors in pituitary tumors and clinical parameters such as patients' age, tumor size, hormonal hypersecretion, and response to octreotide therapy. Forty-two-consecutive patients were enrolled in this trial. Twenty-five of them had nonsecreting pituitary tumors, 11 were acromegalic, and 6 had macro- or microprolactinoma. Scintigraphic images of the head were obtained at 10 min and 24 hours after injection of the radionuclide. In 23 patients, no specific binding of 111In-octreotide was found. Five patients showed a weak positive, 5 had a positive, and 9 a strong positive signal in the region of interest. Uptake of octreotide was significantly correlated with tumor size and age (p < 0.01). Small-size pituitary adenomas were most likely to be scintigraphically receptor-negative, while large suprasellar tumors tended to exhibit a rather strong receptor positivity. Statistical analysis of the data could not confirm the hypothesized correlation between endocrine activity of the pituitary tumors and the scintigraphically proven SST receptor expression in vivo. A positive Octreoscan was not predictive for the result of octreotide therapy.

[Established and new therapeutic approaches in dermatomyositis, polymyositis and overlapping syndromes]

An overview is presented on current antiinflammatory, cytostatic/cytotoxic and immunomodulatory treatments for immunologically mediated inflammatory myopathies with skin involvement. High-dose intravenous immunoglobulin (IVIG) therapy is discussed in the context of recent findings regarding pathogenic mechanisms of autoimmune diseases.

Marked increases in heart rate associated with sevoflurane but not with halothane following suxamethonium administration in children

The changes in heart rate and arterial blood pressure following the administration of suxamethonium in healthy children (mean age 3.8 +/- 0.3 years) during inhalational induction with either sevoflurane (n = 22) or halothane (n = 19) were studied. Heart rate 60s following suxamethonium administration increased significantly in the sevoflurane but not in the halothane group. In the halothane group, four children required intravenous (i.v.) atropine as as result of bradycardia. None of the children in the sevoflurane group developed bradycardia following suxamethonium (P < 0.05). Values of oxygenation, ventilation and age corrected minimal alveolar concentration were comparable at all measurement times. The haemodynamic response to the administration of suxamethonium in children anaesthetized with sevoflurane seems to reflect the stimulation of the autonomic ganglia by suxamethonium whereas this positive chronotropic effect is attenuated or reversed by halothane.

Patient-controlled intranasal analgesia: a method for noninvasive postoperative pain management

Recently, a new device for patient-controlled intranasal analgesia (PCINA) was described, and a pilot study demonstrated promising results with respect to efficacy and patient satisfaction. The present study compares PCINA with intravenous (IV) patient-controlled analgesia (PCA). Fifty orthopedic patients were prospectively studied over an 8-h period on the first day after surgery. The patients were randomly allocated to PCINA group (n = 25) or to an IV PCA group (n = 25). Pain intensity was evaluated at 30-min intervals using a 101-point numerical rating scale. With respect to initial pain intensity, there was no significant intergroup difference. At the 30- to 480-min measurement points pain intensity in the PCINA group (P < 0.0001) and the IV PCA group (P < 0.0001) was significantly less as compared to the initial value. There was no significant intergroup difference in pain intensity. No patient had problems using the PCINA device. The present study demonstrates, that PCINA provides relief of postoperative pain as effectively as IV PCA.

Dysregulation of the polymorphonuclear leukocyte--Candida spp. interaction in HIV-positive patients

OBJECTIVE

In HIV-infected patients there is an increased frequency of fungal infections. Dysregulation of the response of phagocytic cells to fungal pathogens may be involved.

DESIGN

Phagocytosis of Candida spp., consecutive intracellular production of reactive oxygen species, and candicidal activity were analysed in polymorphonuclear leukocytes (PML) from HIV-1-infected patients, who were at stage C3 of the 1993 revised Centers for Disease Control and Prevention classification system, by means of flow cytometry.

METHODS

Phagocytic ability was assessed by measuring uptake of fluorescein isothiocyanate-labelled Candida albicans, C. krusei and C. glabrata. Reactive oxygen intermediate production was estimated by the quantity of dihydrorhodamine-123 converted to rhodamine-123 intracellularly. The candicidal effect was assessed by the propidium iodide uptake of killed yeast cells.

RESULTS

As compared to PML of healthy, HIV-negative controls, PML of AIDS patients exhibited an increased phagocytic activity and a similar ability to generate reactive oxygen products. In contrast, PML of AIDS patients displayed a decreased candicidal activity (P < 0.05 compared to controls).

CONCLUSION

These results suggest that in patients with advanced HIV-1 infection the impairment of non-oxidative killing mechanisms of phagocytic cells may contribute to the high incidence of fungal infections.

[Intubation trauma of the larynx--a literature review with special reference to arytenoid cartilage dislocation]

Trauma to the cricoarytenoid joint represents a rare but serious complication of endotracheal intubation. Subluxation and luxation of the arytenoid cartilage may occur during difficult but also following uncomplicated intubation. Forces on the arytenoid cartilage exerted by the laryngoscope blade or by the distal part of the endotracheal tube may cause anterior and inferior displacement of the arytenoid cartilage. Due to the conventional intubation technique the left arytenoid cartilage is affected most frequently. Posterolateral subluxation is attributed to the pressure exerted on the posterior glottis by the convex part of the shaft of the tube. Systemic diseases (e.g. terminal renal insufficiency, bowel diseases, acromegaly) may cause degeneration of the cricoarytenoid ligaments, thus making the cricoarytenoid joint more susceptible to traumatic dislocation. Persisting alterations of voice, sore throat and pain on swallowing may hint to the diagnosis of arytenoid dislocation. However, stridor and shortness of breath have also been observed. If pharyngo-laryngeal complaints persist, evaluation by laryngologists is mandatory. In addition to indirect and direct laryngoscopy, computerised tomography and electromyography of the larynx play an important role in differentiating arytenoid dislocation from true vocal cord paralysis due to nerve damage. Early operative reposition results in fair prognosis, whereas delayed diagnosis may lead to ankylosis of the cricoarytenoid joint with permanent impairment of the voice and possibly compromised airway protection.

A comparison of sevoflurane with halothane in outpatient adenotomy in children with mild upper respiratory tract infections

STUDY OBJECTIVE

To investigate the efficacy and safety of sevoflurane compared with halothane in pediatric outpatient ear-nose-throat (ENT) surgery during the induction, maintenance, emergence, and recovery of anesthesia.

DESIGN

Prospective, randomized, comparative, open-label study.

SETTING

ENT operating room and postoperative recovery room at a university medical center.

PATIENTS

41 ASA status I and II children between the ages of 2 to 10 years, with mild upper respiratory tract infection (URI).

INTERVENTIONS

Induction and maintenance of anesthesia with either sevoflurane or halothane for outpatient adenotomy, otomicroscopy, and myringotomy.

MEASUREMENTS AND MAIN RESULTS

Induction (means +/- SEM) was significantly shorter in the sevoflurane group (2.6 +/- 0.2 minutes) than in the halothane group (3.2 +/- 0.2 minutes). There was no difference between the two groups with regard to complications that occurred during the induction and maintenance period. The time to emergence and recovery was significantly shorter with sevoflurane than with halothane (means +/- SEM; time to extubation 9.9 +/- 0.98 minutes vs. 13.4 +/- 1.06 minutes, time to eye opening 12.9 +/- 1.6 minutes vs. 24.5 +/- 1.8 minutes, command response time 20.7 +/- 2.5 minutes vs. 36.4 +/- 2.8 minutes). No difference in the incidence of complications during emergence and recovery was found. Evaluation of recovery as assessed by a modified Aldrete score showed that children who had received sevoflurane reached higher scores in the first 30 minutes following the discontinuation of the anesthetic. The Pain/Discomfort Scale demonstrated a difference in the sevoflurane group, with more children being agitated and restless.

CONCLUSION

Sevoflurane provides a safe and rapid anesthetic induction with no differences in complications during the induction, maintenance, and emergence period. With sevoflurane, the time of emergence and recovery was significantly shorter. The characteristics of sevoflurane as evaluated in the present study make it a suitable anesthetic in pediatric outpatient surgery even in the presence of mild URI.