Evaluation of Drinking Water Quality and Bacterial Antibiotic Sensitivity in Wells and Standpipes at Household Water Points in Freetown, Sierra Leone

Water quality surveillance can help to reduce waterborne diseases. Despite better access to safe drinking water in Sierra Leone, about a third of the population (3 million people) drink water from unimproved sources. In this cross-sectional study, we collected water samples from 15 standpipes and 5 wells and measured the physicochemical and bacteriological water quality, and the antimicrobial sensitivity of Escherichia coli (E. coli) in two communities in Freetown, Sierra Leone in the dry and wet seasons in 2021. All water sources were contaminated with E. coli, and all five wells and 25% of standpipes had at least an intermediate risk level of E. coli. There was no antimicrobial resistance detected in the E. coli tested. The nitrate level exceeded the WHO’s recommended standard (>10 parts per million) in 60% of the wells and in less than 20% of the standpipes. The proportion of samples from standpipes with high levels of total dissolved solids (>10 Nephelometric Turbidity Units) was much higher in the rainy season (73% vs. 7%). The level of water contamination is concerning. We suggest options to reduce E. coli contamination. Further research is required to identify where contamination of the water in standpipes is occurring.

Optimising scale and deployment of community health workers in Sierra Leone: a geospatial analysis

Background

Little is known about strategies for optimising the scale and deployment of community health workers (CHWs) to maximise geographic accessibility of primary healthcare services.

Methods

We used data from a national georeferenced census of CHWs and other spatial datasets in Sierra Leone to undertake a geospatial analysis exploring optimisation of the scale and deployment of CHWs, with the aim of informing implementation of current CHW policy and future plans of the Ministry of Health and Sanitation.

Results

The per cent of the population within 30 min walking to the nearest CHW with preservice training increased from 16.1% to 80.4% between 2000 and 2015. Contrary to current national policy, most of this increase occurred in areas within 3 km of a health facility where nearly two-thirds (64.5%) of CHWs were deployed. Ministry of Health and Sanitation-defined ‘easy-to-reach’ and ‘hard-to-reach’ areas, geographic areas that should be targeted for CHW deployment, were less well covered, with 19.2% and 34.6% of the population in 2015 beyond a 30 min walk to a CHW, respectively. Optimised CHW networks in these areas were more efficiently deployed than existing networks by 22.4%–71.9%, depending on targeting metric.

Interpretations

Our analysis supports the Ministry of Health and Sanitation plan to rightsize and retarget the CHW workforce. Other countries in sub-Saharan Africa interested in optimising the scale and deployment of their CHW workforce in the context of broader human resources for health and health sector planning may look to Sierra Leone as an exemplar model from which to learn.

Subarachnoid space of the optic nerve sheath and intracranial hypertension: a macroscopic, light and electron microscopic study

PURPOSE

The optic nerve (ON) is an extension of the central nervous system via the optic canal to the orbital cavity. It is accompanied by meninges whose arachnoid layer is in continuity with that of the chiasmatic cistern. This arachnoid layer is extended along the ON, delimiting a subarachnoid space (SAS) around the ON. Not all forms of chronic intracranial hypertension (ICH) present papilledema. The latter is sometimes asymmetric, unilateral, or absent. The radiological signs of optic nerve sheath (ONS) dilation, in magnetic resonance imaging, are inconsistent or difficult to interpret. The objective of this study was to analyze the anatomy, the constitution, and the variability of the SAS around the ON in its intraorbital segment to improve the understanding of the pathophysiologic mechanism of asymmetric or unilateral or absent papilledema in certain ICH.

METHODS

The study was carried out on nine cadaveric specimens. In four embalmed specimens, macroscopic analysis of the SAS of the ONS were performed, with description about density of the arachnoid trabecular meshwork in three distinct areas (bulbar segment, mid-orbital segment and the precanal segment). In three other embalmed specimens, after staining of SAS by methylene blue (MB), we performed macroscopic analysis of MB progression in the SAS of the ONS. Then, in two non-embalmed specimens, light and electron microscopy (EM) analysis were also done.

RESULTS

On the macroscopic level, after staining of SAS, we found in all cases that MB progressed on 16 mm average throughout the SAS of the ONS without reaching the papilla. In four embalmed specimens, in the SAS of the ONS, the density of the arachnoid trabecular meshwork showed inter-individual variability (100%) and intra-individual variability with bilateral variability (50%) and/or variability within the same ONS (88%). On the microscopic level, the arachnoid trabeculae of the ONS are composed of dense connective tissue. The EM perfectly depicted its composition which is mainly of collagen fibers of parallel orientation.

CONCLUSION

The variability of the SAS around the ONS probably impacts the symmetrical or asymmetrical nature of papilledema in ICH.

Prevalence of drug resistance mutations among ART-naive and -experienced HIV-infected patients in Sierra Leone

Objectives

The aim of this study was to assess the prevalence of HIV drug resistance (HIVDR) in HIV-infected ART-naive and -experienced patients in Sierra Leone.

Patients and methods

We conducted a cross-sectional study of HIV-positive adults aged ≥18 years at Connaught Hospital in Freetown, Sierra Leone in November 2017. Sequencing was performed in the reverse transcriptase, protease and integrase regions, and interpreted using the Stanford HIVDR database and WHO 2009 mutation list.

Results

Two hundred and fifteen HIV-infected patients were included (64 ART naive and 151 ART experienced). The majority (66%) were female, the median age was 36 years and the median ART exposure was 48 months. The majority (83%) were infected with HIV-1 subtype CRF02_AG. In the ART-naive group, the pretreatment drug resistance (PDR) prevalence was 36.7% (14.2% to NRTIs and 22.4% to NNRTIs). The most prevalent PDR mutations were K103N (14.3%), M184V (8.2%) and Y181C (4.1%). In the ART-experienced group, 64.4% harboured resistance-associated mutations (RAMs) and the overall prevalence of RAMs to NRTIs and NNRTIs was 85.2% (52/61) and 96.7% (59/61), respectively. The most prevalent RAMs were K103N (40.7%), M184V (28.8%), D67N (15.3%) and T215I/F/Y (15.3%). Based on the genotypic susceptibility score estimates, 22.4% of ART-naive patients and 56% of ART-experienced patients were not susceptible to first-line ART used in Sierra Leone.

Conclusions

A high prevalence of circulating NRTI- and NNRTI-resistant variants was observed in ART-naive and -experienced HIV-1-infected patients in Sierra Leone. This necessitates the implementation of HIVDR surveillance programmes to inform national ART guidelines for the treatment and monitoring of HIV-infected patients in Sierra Leone.

Prevalence and mortality of cryptococcal disease in adults with advanced HIV in an urban tertiary hospital in Sierra Leone: a prospective study

Background

The global annual estimate for cryptococcal disease-related deaths exceeds 180,000, with three fourth occurring in sub-Saharan Africa. The World Health Organization (WHO) recommends cryptococcal antigen (CrAg) screening in all HIV patients with CD4 count < 100/μl. As there is no previous published study on the burden and impact of cryptococcal disease in Sierra Leone, research is needed to inform public health policies. We aimed to establish the seroprevalence and mortality of cryptococcal disease in adults with advanced HIV attending an urban tertiary hospital in Sierra Leone.

Methods

A prospective cohort study design was used to screen consecutive adult (18 years or older) HIV patients at Connaught Hospital in Freetown, Sierra Leone with CD4 count below 100 cells/mm³ from January to April 2018. Participants received a blood CrAg lateral flow assay (IMMY, Oklahoma, USA). All participants with a positive serum CrAg had lumbar puncture and cerebrospinal fluid (CSF) CrAg assay, and those with cryptococcal diseases had fluconazole monotherapy with 8 weeks followed up. Data were entered into Excel and analysed in Stata version 13.0. Proportions, median and interquartile ranges were used to summarise the data. Fisher’s exact test was used to compare categorical variables.

Results

A total of 170 patients, with median age of 36 (IQR 30–43) and median CD4 count of 45 cells/mm³ (IQR 23–63) were screened. At the time of enrolment, 54% were inpatients, 51% were newly diagnosed with HIV, and 56% were either ART-naïve or newly initiated (≤ 30 days). Eight participants had a positive blood CrAg, giving a prevalence of 4.7% (95% CI: 2.4–9.2%). Of those with a positive CrAg, CSF CrAg was positive in five (62.5%). Five (62.5%) CrAg-positive participants died within the first month, while the remaining three were alive and established on ART at 8 weeks.

Conclusion

A substantial prevalence of cryptococcal antigenaemia and poor outcome of cryptococcal disease were demonstrated in our study. The high mortality suggests a need for the HIV programme to formulate and implement policies on screening and pre-emptive fluconazole therapy for all adults with advanced HIV in Sierra Leone, and advocate for affordable access to effective antifungal therapies.

Seroprevalence of Hepatitis B, Hepatitis C, and Human T-Cell Lymphotropic Virus Infections in HIV-Infected Patients in Sierra Leone

HIV coinfection with hepatitis B virus (HBV), hepatitis C virus (HCV), and human T-cell lymphotropic viruses 1 and 2 (HTLV-1 and HTLV-2) is common because of shared transmission routes. There is no published data on the prevalence of these infections in people living with HIV in Sierra Leone. We conducted a cross-sectional study of 211 HIV-positive patients aged ≥ 18 years in Freetown, Sierra Leone, in November 2017. Plasma samples were analyzed using the chemiluminescent microparticle immunoassay (Architect System, Abbott ARCHITECT Analyzer, Abbott Park, IL. The majority were female (63.5%), with median age 36 years (interquartile range [IQR]: 32-44) and median CD4 count of 396 cells/µL (IQR: 214-534). Sixty patients (28.4%) were newly diagnosed and antiretroviral therapy (ART) naive; 151 patients (71.6%) were ART experienced. The prevalence of the hepatitis B surface antigen (HBsAg), total anti-hepatitis B core antibody, and anti-HCV was 21.7%, 82.9%, and 4.3%, respectively. No cases of HTLV-1 or HTLV-2 were detected. Male gender (P = 0.004) and CD4 < 350 cells/µL (P = 0.017) were associated with the HBsAg positive status.

Causes of hospitalization and predictors of HIV-associated mortality at the main referral hospital in Sierra Leone: a prospective study

Background

HIV infection is a growing public health problem in Sierra Leone and the wider West Africa region. The countrywide HIV prevalence was estimated at 1.7% (67,000 people), with less than 30% receiving life-saving ART in 2016. Thus, HIV-infected patients tend to present to health facilities late, with high mortality risk.

Methods

We conducted a prospective study of HIV inpatients aged ≥15 years at Connaught Hospital in Freetown—the main referral hospital in Sierra Leone—from July through September 2017, to assess associated factors and predictors of HIV-related mortality.

Results

One hundred seventy-three HIV inpatients were included, accounting for 14.2% (173/1221) of all hospital admissions during the study period. The majority were female (59.5%, 70/173), median age was 34 years, with 51.4% (89/173) of them diagnosed with HIV infection for the first time during the current hospitalization. The most common admitting diagnoses were anemia (48%, 84/173), tuberculosis (24.3%, 42/173), pneumonia (17.3%, 30/173) and diarrheal illness (15.0%, 26/173). CD4 count was obtained in 64.7% (112/173) of patients, with median value of 87 cells/μL (IQR 25–266), and was further staged as severe immunosuppression: CD4 < 100 cells/μL (50%, 56/112); AIDS: CD4 < 200 cells/μL (69.6%, 78/112); and late-stage HIV disease: CD4 < 350 cells/μL (83%, 93/112). Fifty-two patients (30.1%, 52/173) died during hospitalization, 23% (12/52) of them within the first week. The leading causes of death were anemia (23.1%, 12/52), pneumonia (19.2%, 10/52), diarrheal illness (15.4%, 8/52) and tuberculosis (13.6%, 7/52). Neurological symptoms, i.e., loss of consciousness (p = 0.04) and focal limb weakness (p = 0.04); alcohol use (p = 0.01); jaundice (p = 0.02); cerebral toxoplasmosis (p = 0.01); and tuberculosis (p = 0.04) were significantly associated with mortality; however, only jaundice (AOR 0.11, 95% CI [0.02–0.65]; p = 0.01) emerged as an independent predictor of mortality.

Conclusion

HIV-infected patients account for a substantial proportion of admissions at Connaught Hospital, with a high morbidity and in-hospital mortality burden. These findings necessitate the implementation of specific measures to enhance early HIV diagnosis and expand treatment access to all HIV-infected patients in Sierra Leone.

Low partner testing in high HIV prevalence setting in Freetown, Sierra Leone: a retrospective study

OBJECTIVE

Despite a 1.5% National HIV prevalence, less than 40% of people living with HIV in Sierra Leone know their status. Limited activities on testing partners of HIV patients could be contributory to this substantial unawareness of HIV status. We carried out a retrospective study aimed at assessing partner testing and HIV prevalence among adults (≥ 15 years) tested using Determine™ and SD Bioline as recorded in the HIV testing registers from January to December 2017 at Connaught Hospital, an urban tertiary hospital in Sierra Leone.

RESULTS

Of the 3808 clients tested for HIV, 2048 (53.8%) were females. The median age was 31 (IQR 24-42) years and 2104 (55.3%) were single. While 3014 (79.1%) had Provider-Initiated Testing and Counseling (PITC), 794 (20.9%) had Client-Initiated Testing and Counseling (CITC). HIV test was positive in 925 (24.3%) {CI 22.9-25.6, P < 0.001} clients. Of the 17 (0.4%) partners tested for HIV, 9 (52.9%) were positive. PITC yielded more HIV positive cases (760, 25.2%) than CITC (165, 20.8%). Partner testing (P = 0.007), female sex (P < 0.001) and PITC (P = 0.006) were associated with a positive HIV diagnosis. With high HIV prevalence and low partner testing, activities on partner testing are needed to improve the response to the epidemic.

Postoperative Thrombotic Microangiopathy following Radical Cystectomy for Bladder Cancer

This report describes the perioperative management of disseminated intravascular coagulation occurring abruptly during a planned cystectomy for non-metastatic bladder papillary carcinoma. Peroperatively, profuse bleeding and an acute decrease in blood pressure were effectively treated by blood transfusions and fresh frozen plasma. Haematological tests indicated the presence of disseminated intravascular coagulation. On the following three days, acute renal failure, peripheral disseminated intravascular coagulation-related thrombocytopenia and haemolytic anemia with schistocytes were suggestive of thrombotic microangiopathy. Treatment by plasma exchange along with haemodialysis was commenced. An aetiological work-up remained negative. After 21 days of treatment, haemodialysis and plasma exchange were stopped. Urological outcome was favourable. The one-year follow-up did not show any residual renal insufficiency and laboratory parameters returned to normal. In the absence of evidence in favour of an infectious, drug-related or immunological aetiology, we postulated that this thrombotic microangiopathy was caused by disseminated intravascular coagulation and that the tumour manipulation during the surgical procedure was the triggering factor.

Understanding why HIV-infected persons disengaged from pre-ART care in Freetown, Sierra Leone: a qualitative study

In countries that have not implemented universal antiretroviral treatment (ART), loss to follow-up (LTFU) during pre-ART care remains a problem. We conducted semi-structured interviews with 41 HIV-infected persons who were LTFU during pre-ART care from a prospective cohort of persons newly diagnosed with HIV infection in Freetown, Sierra Leone, in 2012-2013. Interviews determined whether the participant disengaged or transferred care and explored the reasons for being LTFU. Of the 41 participants, 34 (83%) disengaged from care. For persons who disengaged from care, socioeconomic barriers emerged as a dominant theme in both ART-eligible and -ineligible groups while psychosocial barriers emerged as a dominant theme in the ART-ineligible group. Structural barriers emerged as a dominant theme for participants who transferred care. Interventions designed to address socioeconomic and psychosocial barriers may help reduce disengagement from pre-ART care.

Ebola infection control in Sierra Leonean health clinics: A large cross-agency cooperative project

The Ebola virus disease outbreak occurring in West Africa has resulted in at least 199 cases of Ebola in Sierra Leonean health care workers, many as a result of transmission occurring in health facilities. The Ministry of Health and Sanitation of Sierra Leone recognized that improvements in infection prevention and control (IPC) were necessary at all levels of health care delivery. To this end, the U.S. Centers for Disease Control and Prevention, United Nations Children's Fund, and multiple nongovernmental organizations implemented a national IPC training program in 1,200 peripheral health units (PHUs) in Sierra Leone. A tiered training of trainers program was used. Trainers conducted multiday trainings at PHUs and coordinated the delivery of personal protective equipment (gloves, gowns, masks, boots) and infection control supplies (chlorine, buckets, disposable rags, etc) to all PHU staff. Under the ongoing project, 4,264 health workers have already been trained, and 98% of PHUs have received their first shipment of supplies.

Management program decreases postoperative nausea and vomiting in high-risk and in general surgical patients: a quality improvement cycle

BACKGROUND

Preventing postoperative nausea and vomiting (PONV) is a major priority for postsurgical patient care. Our objective was to assess the efficacy of a multimodal postoperative nausea and vomiting (PONV) approach, which was associated with a continuous quality improvement program, in maintaining a low PONV incidence in the PACU.

METHODS

Consecutive adult patients scheduled for surgery (ambulatory surgery or not) were prospectively included. PONV data were recorded in the PACU and over a 24-hour period. The management program was based on a multimodal approach with both changes in anesthetic techniques and anti-emetics, and on a three-stage protocol including: 1) phase I: institutional practice phase based on prospective observational study; 2) protocol implementation; 3) phase II: prospective observational study associated with feedback, scientific session and evaluation to guideline adherence. We used the Apfel risk scoring system to identify patients at high risk of PONV. Feedback with audit results and didactic sessions were scheduled quarterly in the Phase II.

RESULTS

Thirty-seven/395 (9.4%) and 151/3864 (3.9%) patients experienced PONV in the PACU during Phase I and Phase II respectively (P<0.001). Among the patients with an Apfel risk score that included at least two risk factors, 16.6% and 4.2% experienced PONV in the PACU during Phase I and Phase II respectively (P<0.001).

CONCLUSION

We highlight the association with a sharp decrease in PONV incidence over a one-year period and a multimodal PONV approach using feedback to clinicians associated with continuous quality improvement program.

Cerebral blood flow modulation by transcutaneous cranial electrical stimulation with Limoge's current

OBJECTIVES

Transcutaneous cranial electrical stimulation (TCES) delivers a high-frequency (166 kHz) pulsed biphasic balanced current with a pulse repetition frequency of 100 Hz with 40% duty cycle through a negative electrode and two positive electrodes over the skull. TCES has a proven ability to potentiate anesthesia and analgesia, although the physiological mechanisms of this effect remain unclear. We hypothesized that the mechanism is a modulation of CBF in the central endogenous opioid system. This study aimed at determining the effects of TCES on CBF to elucidate its physiological mechanism.

METHODS

Thirty-six healthy volunteers were randomly assigned to active or placebo TCES, and all assessments were double blind. TCES was performed using the Anesthelec™ device. In the stimulated group, an active cable was used, and in the control group (sham), the cable was inactive. CBF was measured by XeCT™ before and after two hours of TCES.

RESULTS

Globally, CBF was unchanged by TCES. However, locally, TCES induced a significant CBF decrease in the brainstem and thalamus, which are structures involved in pain and anxiety (TCES and control CBF decrease were 18.5 and 11.9 mL/100g brain tissue/min, respectively).

CONCLUSION

TCES can modulate local CBF but it has no effect on overall CBF. [Clinical Trials. gov number: NCT00273663].

Hemangioblastoma of the corpus callosum: A case report and review of the literature on its origin

A third case of corpus callosum hemangioblastoma (HB) is presented. With no preoperative embolization, surgery was uneventful and the postoperative course was excellent. Based on the literature, we attempted to clarify the histogenesis of HB and to explain why they are exceptional in the supratentorial region in contrast to the posterior cranial fossa. The VHL gene is expressed particularly in Purkinje cells of the cerebellum, but this expression is also possible in supratentorial structures. Its mutation leads to developmental arrest of angioblasts that become potentially neoplastic cells. These CD133-positive pluripotent neoplastic angioblasts, similar to stem cells, may be immature HB in the brain. They also express VEGF, coexpress Epo/EpoR, and are capable of differentiation into primitive vascular structures. This coexpression may not only mediate developmental stagnation, but may also induce HB proliferation. Therefore, HB tumorigenesis may be initiated during embryogenesis and may originate from angiomesenchyma because of the expression of three cell types (stromal cells, pericytes, and endothelial cells) in vimentin. Their capacity for proliferation and differentiation in HB depends on the microenvironment.

Wound infiltration with magnesium sulphate and ropivacaine mixture reduces postoperative tramadol requirements after radical prostatectomy

PURPOSE

This prospective, randomized, double-dummy study was undertaken to compare the effects of magnesium sulphate (MgSO(4)) administered by the intravenous vs. the infiltration route on postoperative pain and analgesic requirements.

METHODS

Forty ASA I or II men scheduled for radical retropubic prostatectomy under general anaesthesia were randomized into two groups (n=20 each). Two medication sets A and B were prepared at the pharmacy. Each set contained a minibag of 50 ml solution for IV infusion and a syringe of 45 ml for wound infiltration. Group MgSO(4).IV patients received set A with 50 mg/kg MgSO(4) in the minibag and 190 mg of ropivacaine in the syringe. Group MgSO(4)/L received set B with isotonic saline in the minibag and 190 mg of ropivacaine +750 mg of MgSO(4) in the syringe. The IV infusion was performed over 30 min at induction of anaesthesia and the surgical wound infiltration was performed during closure. Pain was assessed every 4 h, using a 100-point visual analogue scale (VAS). Postoperative analgesia was standardized using IV paracetamol (1 g/6 h) and tramadol was administered via a patient-controlled analgesia system. The follow-up period was 24 h.

RESULTS

The total cumulative tramadol consumption was 221 +/- 64.1 mg in group MgSO4.IV and 134 +/- 74.9 mg in group MgSO(4).L (P<0.01). VAS pain scores were equivalent in the two groups throughout the study. No side-effects, due to systemic or local MgSO(4) administration, were observed.

CONCLUSION

Co-administration of MgSO(4) with ropivacaine for postoperative infiltration analgesia after radical retropubic prostatectomy produces a significant reduction in tramadol requirements.

Sublingual oxybutynin reduces postoperative pain related to indwelling bladder catheter after radical retropubic prostatectomy †

BACKGROUND

Bladder discomfort related to an indwelling catheter can exacerbate postoperative pain. It mimics overactive bladder syndrome that is resistant to conventional opioid therapy. Muscarinic receptor antagonists are effective for treatment of the overactive bladder. The aim of this study was to assess the efficacy of oxybutynin in the management of postoperative pain after radical prostatectomy.

METHOD

Forty-six ASA I or II men undergoing radical retropubic prostatectomy under general anaesthesia were randomly assigned to two groups, in a double-blind fashion: Group O and Group P (n = 23 each). Group O and Group P received, respectively, sublingual oxybutynin 5 mg or placebo every 8 h during the 24 h after surgery. A 16F Foley catheter was placed during the vesico-urethral anastomosis and the balloon inflated with 10 ml of saline. Pain was assessed in the recovery room starting 10 min after extubation using a 100-point visual analogue scale (VAS). The patients were asked to specify whether pain was related to the surgical incision or bladder pain. Standardized postoperative analgesia included acetaminophen and tramadol administered via a patient-controlled analgesia system.

RESULTS

The incidence of bladder catheter pain was 65% (15 of 23 patients) in Group P compared with 17% (4 of 23 patients) in Group O (P < 0.01). Overall VAS scores at rest were significantly lower in Group O. Cumulative tramadol consumption was 322.9(124.3) mg [mean(sd)] in Group P and 146(48) mg in Group O (P < 0.01). No oxybutynin-related side-effects were reported.

CONCLUSIONS

Sublingual oxybutynin is an effective treatment for postoperative pain after radical retropubic prostatectomy and produces a significant reduction in tramadol requirements.

Intravenous magnesium sulphate decreases postoperative tramadol requirement after radical prostatectomy*

BACKGROUND

The purpose of this study was to assess whether the addition of intravenous magnesium sulphate (Mg) at the induction of anaesthesia to a balanced anaesthetic protocol including wound infiltration, paracetamol and tramadol resulted in improved analgesic efficiency after radical prostatectomy.

METHODS

We conducted a randomized, double-blind, controlled study. Thirty ASA I or II males scheduled to undergo radical retropubic prostatectomy with general anaesthesia were prospectively assigned to one of the two groups (n = 15 each). The Mg group (Gr Mg) received 50 mg kg-1 of MgSO4 in 100 mL of isotonic saline over 20 min immediately after induction of anaesthesia and before skin incision. The patients in the control group (Gr C) received the same volume of saline over the same period. At the time of abdominal closure, wound infiltration with 190 mg (40 mL) of ropivacaine was performed in both groups. Pain was assessed by a 10-point visual analogue scale in the recovery room starting from the time of tracheal extubation. Standardized postoperative analgesia included paracetamol and tramadol administered via a patient-controlled analgesia device.

RESULTS

In the postoperative period, both groups experienced an identical pain course evolution. Cumulative mean tramadol dose after 24 h was 226 mg in the magnesium group and 446 mg in the control group (P < 0.001). Postoperative nausea occurred in two patients in each group. Two vs. eight patients required analgesic rescue in magnesium and control groups, respectively (P = 0.053).

CONCLUSIONS

This study shows that intravenous magnesium sulphate reduces tramadol consumption when used as a postoperative analgesic protocol in radical prostatectomy.

Comparative overview of brain perfusion imaging techniques

Numerous imaging techniques have been developed and applied to evaluate brain hemodynamics. Among these are: Positron Emission Tomography (PET), Single Photon Emission Computed Tomography (SPECT), Xenon-enhanced Computed Tomography (XeCT), Dynamic Perfusion-computed Tomography (PCT), Magnetic Resonance Imaging Dynamic Susceptibility Contrast (DSC), Arterial Spin-Labeling (ASL), and Doppler Ultrasound. These techniques give similar information about brain hemodynamics in the form of parameters such as cerebral blood flow (CBF) or volume (CBV). All of them are used to characterize the same types of pathological conditions. However, each technique has its own advantages and drawbacks. This article addresses the main imaging techniques dedicated to brain hemodynamics. It represents a comparative overview, established by consensus among specialists of the various techniques. For clinicians, this paper should offers a clearer picture of the pros and cons of currently available brain perfusion imaging techniques, and assist them in choosing the proper method in every specific clinical setting.

Comparison of the anaesthetic requirement with target-controlled infusion of propofol to insert the laryngeal tube vs. the laryngeal mask

BACKGROUND AND OBJECTIVE

The target effect-site concentration of propofol to insert a laryngeal mask airway was recently reported as almost 5 microg mL(-1). The present study aimed to determine the target effect-site concentration with target-controlled infusion of propofol to place classical larnygeal mask airway or current laryngeal tube in adult patients.

METHODS

We included 40 patients scheduled for short gynaecological and radiological procedures under general anaesthesia in a randomized, double-blind manner using the Dixon's up-and-down statistical method. Monitoring included standard cardiorespiratory monitors, and bispectral index monitoring was used for all patients. Anaesthesia was conducted with a target-controlled infusion system: Diprifusor. The initial target plasma concentration of propofol was 5 microg mL(-1), and was changed stepwise by 0.5 microg mL(-1) increments according to Dixon's up-and-down method. Criteria for acceptable insertion were: Muzi's score < or = 2, and mean arterial blood pressure, heart rate or bispectral index variation <20% the baseline values.

RESULTS

Target effect-site concentration of propofol required to insert laryngeal tube was 6.3 +/- 0.3 microg mL(-1) with Dixon method and ED50 was 6.1 microg mL(-1) (5.9-6.4) with logistic regression method. In the case of larnygeal mask airway they were 7.3 +/- 0.2 microg mL(-1) (Dixon method) and 7.3 microg mL(-1) (7.1-7.5; with logistic regression) respectively (P < 0.05). ED95 (logistic regression) was 6.8 microg mL(-1) (5.9-7.6) for laryngeal tube and 7.7 microg mL(-1) (7.3-8.0) for larnygeal mask airway (P < 0.05). Haemodynamic incidents were 55% in the larnygeal mask airway group vs. 30% in the laryngeal tube group (P < 0.05).

CONCLUSIONS

The target effect-site concentration of propofol for insertion of laryngeal tube was lower than for larnygeal mask airway (P < 0.05), with a consequent reduction of the propofol induced haemodynamic side-effects.

Effects of perioperative alpha1 block on haemodynamic control during laparoscopic surgery for phaeochromocytoma

BACKGROUND

Laparoscopic surgery for phaeochromocytoma can cause excessive catechol amine release with severe hypertension and sinus tachycardia. i.v. calcium antagonists may be used to prevent increases in blood pressure during phaeochromocytoma resection. We investigated the effects of perioperative alpha(1) adrenergic block with urapidil on intraoperative haemodynamic events. The aim was to block the alpha(1) adrenergic receptors before any acute catecholamine release, to prevent any severe rise in blood pressure.

METHODS

Eighteen patients with a phaeochromocytoma received a continuous i.v. infusion of urapidil 10-15 mg h(-1) for 3 days before surgery and until the adrenal gland had been removed. Plasma catecholamine concentrations were measured before surgery, after induction of anaesthesia, at the end of pneumoperitoneal insufflation, during gland manipulation, after gland resection, and in the recovery room after extubation. Arterial pressure was recorded concomitantly. Hypertensive events were treated with boluses of nicardipine with or without esmolol.

RESULTS

All patients had the adrenal tumour removed without any severe rise in blood pressure or other complication. Creation of a pneumoperitoneum and adrenal gland manipulation induced significant catecholamine release associated with hypertension in 6 and 12 patients, respectively. No correlation was found between hypertensive events and plasma catecholamine levels suggesting alpha(1) receptor block with urapidil is efficacious.

CONCLUSIONS

Perioperative alpha(1) block using i.v. urapidil is a safe and efficient alternative during surgical management of phaeochromocytoma.

[Anterior sacral root stimulation with dorsal rhizotomy (Brindley technique)]

Patients with spinal cord lesions are exposed to vesico-sphincter dysfunctions which can aggravate the vital or functional prognosis. The pathophysiological characteristics of these neurogenic bladders explains the usefulness of surgical treatment. The objective of the Brindley technique is to improve both voiding and effective continence. Any patient with a stable supra-sacral spinal cord lesion (paraplegia, tetraplegia) with a reflex bladder (incontinence, vesico-sphincter dyssynergia resistant to medical treatment with the risk of upper urinary tract involvement) can benefit from the Brindley technique. The electrodes are placed on the anterior sacral roots in order to obtain the desired micturation. Posterior sacral rhizotomies are indispensable to the technique as they suppress detrusor and sphincter hyperreflexia and improve continence thereby protecting the upper urinary tract. About 90% of the patients considered have an improved quality of life after implantation of the Brindley stimulator. The bladder capacity was constantly improved and the majority of the patients become continent. Micturation was excellent with low residual volume and low rate of urinary tract infections. Complications are analyzed in this review of the literature. The Brindley technique is an excellent alternative to medical treatment in these highly distressed patients. It restores satisfactory continence and improves psychological as well as economical constraints related to auto/hetero catheterisations performed several times a day.

[Osmotic cerebral oedema: the role of plasma osmolarity and blood brain barrier]

There are five types of oedema: vasogenic, cytotoxic, interstitial, hyperemic and osmotic. The differences lie on the type and localization of the oedema, the state of the blood-brain barrier (BBB) and the pathological context. Under physiological conditions, the osmolarity of extra cellular fluids (ECFs) is equal on both sides of the BBB. However, the pathophysiological variations of circulating osmolarity (including acute hyponatremia and hypernatremia) do not affect, at the same time, the osmolarity of cerebral ECFs. This situation generates an osmotic gradient on either side of the BBB. The latter, if intact, behaves like a semi-permeable membrane allowing water transport according to the osmotic laws. Depending on its direction, water movement could induce cerebral liquid inflation (i.e. osmotic oedema) or cerebral dehydration. In case of osmotic insult, cerebral cell modify their active osmotic molecular contents in order to limit volume variation. There are two types of osmoactive molecules, organic (i.e. ideogenic osmoles: amino acids, polyols and trimethylamines) and non organic (i.e. electrolytes). In the event of plasma hypotonicity, cerebral cells expel active osmotic molecules to reduce the osmotic gradient and water movement thereby reducing edema. The opposite reaction is observed in the case of hypertonic insult. This cerebral osmoregulation becomes more effective, the slower the osmotic disorder. It explains, for example, why patients with chronic and severe hyponatremia could be asymptomatic. Severe osmotic oedema is observed mainly in water intoxication, acute hyponatremia or too rapid reduction of hyperosmolarity. However, osmotic oedema is not limited to extreme clinical circumstances. Hyponatremia, even modest, could modify cerebral blood volume and impair osmoregulation. Generally these minor modifications do not affect normal brain tissue. In the presence of cerebral lesion, osmoregulation operates only in areas of preserved BBB. The pathological zones are therefore exposed to osmotic oedema (even in cases of moderate hyponatremia) with deterioration of both clinical status and intracranial pressure. This authentic phenomenon could be insidious and difficult to differentiate from osmotic central oedema. Hyponatremia constitutes an authentic secondary cerebral insult of systemic origin, an entity clearly identified by experimental studies to justify the choice between crystalloids and colloids in neuroanaesthesia and neurointensive care. These studies have revealed an increase in water content in normal brain tissues after administration of hypotonic solutions. The increase in plasma osmolarity as a treatment modality using mannitol or hypertonic saline is based on the same concepts. The most remote indication is the occurrence of a reactive mydriasis in the context of trauma for example. More recently, therapeutic hypernatremia has been proposed to control intracranial hypertension.

Dorsal rhizotomy with anterior sacral root stimulation for neurogenic bladder

A spinal cord lesion above the sacral micturition center results in a loss of voluntary control and development of bladder sphincter dysynergia with hyperreflexia of the detrusor and spasticity of the sphincter. Sacral rhizotomy and implantation of an anterior sacral root stimulator appears as an effective method for the treatment not only of voiding dysfunction but also of defecation and sexual disturbance. The surgical technique is described as are the clinical and electrophysiological controls. The results of our series of operated patients with intradural implantation and sacral deaffentation show a constant improvement. 90% have satisfactory continence and no longer require an incontinence appliance. Bladder capacity and compliance have increased to 120% and urethral closure pressure has decreased. 80% have complete voiding or a post-void residue of not more than 50 ml. So, urinary infection rate is dramatically decreased.

[Cerebrospinal fluid shunting: anesthetic particularities]

The symptomatic treatment of hydrocephalus remains cerebrospinal fluid (CSF) drainage to an external reservoir (external CSF drainage) or to an internal cavity mainly the peritoneum or the right atrium via a unidirectional valve (internal CSF drainage) and finally by endoscopic ventriculocisternostomy. Local anaesthesia is adequate for external CSF drainage in adults and children above 10 years while general anaesthesia is required in all other cases. The main problems encountered in these patients are difficult intubation and full stomach associated with increased intracranial pressure. The anaesthetic approach should favour homeostasis. With the exception of ketamine and enflurane, the majority of anaesthetic drugs can be used. Anti-epileptic drug are mandatory. Antibioprophylaxis mainly against staphylococcus is systematic in internal CSF drainage. Rapid emergence from anaesthesia and extubation should be encouraged. Complications (infectious, mechanical and bleeding kinds) are frequent and are often the cause of reinterventions or revisions of the device, exposing the patients to iterative anaesthesia. Furthermore, patients with shunts are at risk of malfunction of the device when exposed to situations like pregnancy, magnetic resonance imaging, or laparoscopy. Under these circumstances, it is recommended to associate the neurosurgical team in the management of these patients and to verify that the shunt is working well before and after the procedure or event.

Effects of premedication with oral hydroxyzine on patient motion during inhalation of 32% xenon for regional cerebral blood flow mapping

Because of its anesthetic properties, inhalation of 30-35% Xenon is associated with uncontrolled patient motion in 3-15% of the cases. This constitutes a major setback to regional cerebral blood flow studies with Xenon-enhanced computed tomography (Xe-CT CBF). The present study attempted to determine the effects of oral premedication with hydroxyzine (H) in the control of motion. Patients scheduled for Xe-CT CBF, aged 20-55 years, were randomly allocated to 3 groups: H 50 mg (n = 41), H 100 mg (n = 36) or Placebo (n = 43). The drugs were administered orally 90 minutes before Xenon inhalation. This consisted a gas mixture of 32% Xe and 25% oxygen. Motion was classified as controlled or uncontrolled depending on whether CBF data acquisition was possible or not. Anxiolysis and sedation were evaluated by a visual analogue scale. Motion was significantly reduced in the H 50 mg (0.8% vs 2.5% in the H 100 mg and 6.7% in the Placebo group). An anxiolytic effect of hydroxyzine was suggested.

Assessment of regional cerebral blood flow by xenon-enhanced computed tomography during mastication in humans

It is suggested that mastication stimulates the brain and accelerates its energy-consuming metabolism. This study was designed to determine its effects on regional cerebral blood flow (rCBF) using xenon-enhanced computed tomography (Xe-CT). Seven male volunteers, aged 24-57 years, inhaled 30% xenon in a 4 minutes wash-in and 4 minutes wash-out protocol. CT was scanned every 54.5 seconds. The subjects were instructed to chew a gum continuously at a rate of 1 bite per second except at the time of CT scanning (5.5 seconds). A second CBF was done 20 minutes later. Subtraction (mastication-baseline) maps were created. CT images were taken at three levels so as to include the cortex, basal ganglia, limbic system, brainstem and cerebellum. The results demonstrated a significant rCBF increase in the fronto-temporal cortex, caudate nucleus, thalamus and minor increase in the rolandic areas, insula, cingulate and cerebellum. Further studies are needed to validate the clinical significance of these findings.

Epidemiology of elderly patients' burns in the South West of France

A retrospective study of 716 patients aged 60 years and above (324 men, 392 women) was undertaken in order to determine quality control in burns management in the South West of France. The following epidemiological data was obtained: high hospitalization rate (7 per cent of the general admissions); monthly and seasonal periodicity; predominance of indoor accidents (86 per cent) with domestic accidents being more frequent in women (63 vs. 37 per cent). Outdoor accidents were mainly recreational and were five times more frequent in men than in women. The overall mortality was 39 per cent and was influenced by the burns extent, depth, predisposing factors and early management. More burns occurred in urban areas (53 per cent) but mortality was higher in patients from rural areas (62 vs. 38 per cent). It was observed that delay in management, especially fluid resuscitation of patients from the rural areas, was partly responsible for this outcome. Propositions were made to diffuse more information on the importance of early management of burns in rural areas.

Regional cerebral blood flow measurements with Xenon-CT in the prediction of delayed encephalopathy after carbon monoxide intoxication

Reported evaluations of CBF with Xe/CT were performed in 11 patients during the lucid interval following CO intoxication. Results were compared with clinical and SPECT data. Two patients developed neuropsychiatric behavior (delayed encephalopathy) one month following the initial recovery. The symptoms persisted in one of them 15 months later. Their CBF values as well as those in most of the other patients, monitored at the basal ganglia and white matter areas, were in relation with the clinical outcome, However, further studies with a larger number of patients, are needed to confirm the predictive significance of Xe/CT measurements for the long term sequelae of CO poisoning.

Magnetization transfer on in vitro circulating blood: implications for time-of-flight MR angiography

Effects of magnetization transfer were evaluated in vitro on circulating blood. Various velocities were tested from 0 to 72 cm/second. Decrease signal intensity caused by magnetization transfer effects was inversely proportional to inflow velocity. It reached 10% at very low velocities and disappeared at velocities higher than 30 cm/second.

[Methods for measuring spinal cord blood flow]

This study aimed to review the techniques used most currently for measuring spinal cord blood blow flow (SCBF) in animals, i.e. the hydrogen clearance, labelled microspheres, 133Xe clearance and 14C-antipyrine autoradiographic methods. All four techniques may only be used in animals, because of their invasiveness. Flow figures varied greatly with the method, the spinal level at which measurements were carried out, and the species of animal. However, results tend to suggest that SCBF is very similar to cerebral blood flow in that it is controlled by chemical, autoregulatory and metabolic factors. Approaches to measuring SCBF in man may be made using stable xenon-enhanced computed tomographic imaging (Xes-CT) in the same way as for measuring cerebral blood flow. The calculation of SCBF is based on Fick's principle transformed by Kety and Schmidt. After a reference CT section has been obtained, twelve 8 mm thick sections are carried out whilst the patient breathes a 30% xenon-70% air/oxygen mixture. This series of views enables the SCBF to be calculated in four steps. Quantitative analysis in eight human subjects gave a mean SCBF of 58.8 +/- 5.96 ml x 100 g-1 x min-1. However, this method has a low signal to noise ratio. Moreover, the qualitative analysis of the parametric views of flow demonstrate tissue heterogeneity, partly due to the patient's movements (breathing movements). However, the method is non invasive, safe, and reproducible. As it can measure very low values of blood flow, the study of ischaemic spinal lesions is made possible, although some technical and software improvements are still required.