Musa Sesay

Comparative Overview of Brain Perfusion Imaging Techniques

Background and Purpose— Numerous imaging techniques have been developed and applied to evaluate brain hemodynamics. Among these are positron emission tomography, single photon emission computed tomography, Xenon-enhanced computed tomography, dynamic perfusion computed tomography, MRI dynamic susceptibility contrast, arterial spin labeling, and Doppler ultrasound. These techniques give similar information about brain hemodynamics in the form of parameters such as cerebral blood flow or cerebral blood volume. All of them are used to characterize the same types of pathological conditions. However, each technique has its own advantages and drawbacks. Summary of Review— 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. Conclusions— For clinicians, this article should offer a clearer picture of the pros and cons of currently available brain perfusion imaging techniques and assist them in choosing the proper method for every specific clinical setting.

Awake craniotomy vs surgery under general anesthesia for resection of supratentorial lesions.

BACKGROUND:The use of an awake craniotomy in the treatment of supratentorial lesions is a challenge for both patients and staff in the operation theater. OBJECT:To assess the safety and effectiveness of an awake craniotomy with brain mapping in comparison with a craniotomy performed under general anesthesia. METHODS:We prospectively compared 2 groups of patients who underwent surgery for supratentorial lesions: those in whom an awake craniotomy with intraoperative brain mapping was used (AC group, n = 214) and those in whom surgery was performed under general anesthesia (GA group, n = 361, including 72 patients with lesions in eloquent areas). The AC group included lesions in close proximity to the eloquent cortex that were surgically treated on an elective basis. RESULTS:Globally, the 2 groups were comparable in terms of sex, age, American Society of Anesthesiologists score, pathology, size of lesions, quality of resection, duration of surgery, and neurological outcome, and different in tumor location and preoperative neurological deficits (higher in the AC group). However, specific data analysis of patients with lesions in eloquent areas revealed a significantly better neurological outcome and quality of resection (P < .001) in the AC group than the subgroup of GA patients with lesions in eloquent areas. Surgery was uneventful in AC patients and they were discharged home sooner. CONCLUSION:AC with brain mapping is safe and allows maximal removal of lesions close to functional areas with low neurological complication rates. It provides an excellent alternative to craniotomy under GA.

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.

Intracranial meningioma surgery in the ninth decade of life.

OBJECTIVEThe aims of this study are to assess the surgical outcome of elderly patients aged 80 years or more, to analyze the factors influencing postoperative course, and to propose a grading system to standardize the surgical indication of intracranial meningioma in the elderly. METHODSBetween 1990 and 2005, we surgically treated 74 consecutive patients aged 80 years or more for intracranial meningiomas (47 women, 27 men; mean age, 82 yr; age range, 80–90 yr). The median follow-up period was 94 months (range, 15–147 mo). We retrospectively analyzed the factors influencing surgical outcome and retained the significant factors to form the Sex, Karnofsky Performance Scale, American Society of Anesthesiology Class, Location of Tumor, and Peritumoral Edema (SKALE) grading system. RESULTSThere was no perioperative mortality, and the 1-year mortality rate was 9.4%. Postoperative mortality was lower in women with a Karnofsky Performance Scale score of 60 or greater, an American Society of Anesthesiology Class of 1 or 2, a noncritical tumor location, and a moderate or absent peritumoral edema. Patients with a SKALE score of more than 8 had an excellent outcome, whereas those with a SKALE score of less than 8 had a poor outcome. The rate of postoperative complications was 9.4%. Large tumors, critical locations, severe peritumoral edema, and total surgical excision were associated with a higher risk of postoperative complications. CONCLUSIONSurgery of intracranial meningioma in elderly patients is feasible when the SKALE score is 8 or greater. Prospective studies are required to validate this grading system.

Intraosseous lidocaine provides effective analgesia for percutaneous vertebroplasty of osteoporotic fractures

PurposeTo assess the safety and efficacy of intraosseous lidocaine (IL), in comparison with iv nalbuphine and propacetamol (NP) for analgesia during percutaneous vertebroplasty (PV) in order to avoid general anesthesia in elderly patients.MethodsPatients (age 68 ±13 yr, weight 66 ±6 kg) undergoing PV for osteoporotic fractures were randomized prospectively into two groups: NP(n = 50)and IL(n = 50). All patients were premedicated (oral hydroxyzine I mg·kg−1) and had skin infiltration with 5 ml_ of 1% lidocaine prior to vertebral puncture. Thirty minutes before the procedure, Group NP received, in a blinded manner, SO ml_ of iv nalbuphine (0.3 mg·kg−1) and propacetamol (30 mg·kg−1) while Group IL received 50 mL of iv saline. During vertebral puncture, Groups NP and IL received, in a blinded manner, I mL·10 kg−1 of intraosseous saline and 1% lidocaine respectively. Pain was assessed during vertebral puncture and cement injection with a four-point verbal rating scale. Additionally, lidocaine plasma kinetics were obtained in I I IL patients.ResultsAnalgesic efficacy was similar in the IL and NP groups (85 vs 84%). Group NP had more side effects. Lidocaine peak recorded concentration was 2.6 ±0.1 μg·mL−1 i.e., about three times less than the reported toxic limits.ConclusionIL is as effective as the association of iv NP for analgesia in PV. However, considering that both protocols were insufficient in about 15% of cases, other modalities are needed to further improve analgesia and avoid general anesthesia during vertebroplasty.RésuméObjectifÉvaluer l’efficacité et la sécurité d’une injection intraosseuse de lidocaïne (IL) comparée à une sédation iv à base de nalbuphine et de propacétamol (NP) pour l’analgésie des vertébroplasties percutanées (VP) afin d’éviter l’anesthésie générale chez des patients âgés.MéthodeCent patients devant subir une l’P sont prospectivement randomisés en deux groupes: 30 min avant la procédure, le groupe NP reçoit en aveugle 50 mL d’un mélange iv de nalbuphine (0,3 mg·kg−1) et de propacétamol (30 mg·kg−1) tandis que le groupe IL reçoit 50 mL iv de solution salée. Tous les patients reçoivent une prémédication avec de l’hydroxyzine (I mg·kg−1) et ont une infiltration cutanée avant la ponction vertébrale avec 5 mL de lidocaine I %. Pendant la ponction vertébrale, le groupe NP reçoit à son tour une solution salée alors que le groupe IL reçoit I mL· 10 kg−1 de lidocaïne I %. La douleur est évaluée pendant l’opération par une échelle verbale à quatre degrés. Un profil cinétique de la lidocaïne plasmatique est réalisé chez les 11 premiers patients.RésultatsUne analgésie efficace est constatée dans les groupes IL et NP dans 85 et 84 % des cas respectivement. Le groupe NP présente plus d’effets secondaires. Le pic plasmatique de lidocaïne circulante est 2,6 ±0,1 μg·mL−1 soit trois fois moins que les limites toxiques.ConclusionLa lidocaïne intra-osseuse procure la même analgésie que l’association iv de NP pour les l’P. Étant donné que les deux protocoles sont insuffisants dans environ 15% des cas, d’autres associations sont nécessaires pour améliorer encore l’analgésie et éviter l’anesthésie générale.

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.

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 μg 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 Dixons 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 μg mL−1, and was changed stepwise by 0.5 μg mL−1 increments according to Dixons up‐and‐down method. Criteria for acceptable insertion were: Muzis score ≤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 μg mL−1 with Dixon method and ED50 was 6.1 μg mL−1 (5.9‐6.4) with logistic regression method. In the case of larnygeal mask airway they were 7.3 ± 0.2 μg mL−1 (Dixon method) and 7.3 μg mL−1 (7.1‐7.5; with logistic regression) respectively (P < 0.05). ED95 (logistic regression) was 6.8 μg mL−1 (5.9‐7.6) for laryngeal tube and 7.7 μg 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.

Benefits of intravenous lidocaine on post-operative pain and acute rehabilitation after laparoscopic nephrectomy

Background and Aims: Intravenous (I.V.) lidocaine has analgesic, antihyperalgesic and anti-inflammatory properties and is known to accelerate the return of bowel function after surgery. We evaluated the effects of I.V. lidocaine on pain management and acute rehabilitation protocol after laparoscopic nephrectomy. Materials and Methods: A total of 47 patients scheduled to undergo laparoscopic nephrectomy were included in a two-phase observational study where I.V. lidocaine (1.5 mg/kg/h) was introduced, in the second phase, during surgery and for 24 h post-operatively. All patients underwent the same post-operative rehabilitation program. Post-operative pain scores, opioid consumption and extent of hyperalgesia were measured. Time to first flatus and 6 min walking test (6MWT) were recorded. Results: Patient demographics were similar in the two phases (n = 22 in each group). Lidocaine significantly reduced morphine consumption (median [25-75% interquartile range]; 8.5 mg[4567891011121314151617] vs. 25 mg[1920212223242526272829303132]; P < 0.0001), post-operative pain scores (P < 0.05) and hyperalgesia extent on post-operative day 1-day 2-day 4 (mean ± standard deviation (SD); 1.5 ± 0.9 vs. 4.3 ± 1.2 cm (P < 0.001), 0.6 ± 0.5 vs. 2.8 ± 1.2 cm (P < 0.001) and 0.13 ± 0.3 vs. 1.2 ± 1 cm (P < 0.001), respectively). Time to first flatus (mean ± SD; 29 ± 7 h vs. 48 ± 15 h; P < 0.001) and 6MWT at day 4 (189 ± 50 m vs. 151 ± 53 m; P < 0.001) were significantly enhanced in patients with i.v. lidocaine. Conclusion: Intravenous (I.V.) lidocaine could reduce post-operative morphine consumption and improve post-operative pain management and post-operative recovery after laparoscopic nephrectomy. I.V. lidocaine could contribute to better post-operative rehabilitation.

Real-Time Heart Rate Variability and Its Correlation with Plasma Catecholamines During Laparoscopic Adrenal Pheochromocytoma Surgery

BACKGROUND:We studied sympathovagal activity using real-time heart rate variability (HRV) and determined its relationship with plasma catecholamines to characterize short-term cardioregulatory mechanisms during laparoscopic adrenal pheochromocytoma surgery. METHODS:We recruited 20 patients with pheochromocytoma (Group P) and 20 with incidentaloma (Group I). HRV, systolic blood pressure and heart rate were continuously monitored. The low frequency and high frequency spectra denoted, respectively, sympathetic and parasympathetic activity. The low frequency/high frequency (LF/HF) ratio represented sympathovagal balance. Blood samples for epinephrine and norepinephrine assays were collected before, during, and after surgery. After log transformation of the repeated measures, a linear regression model was applied on their mean values. The correlation coefficients among variables were calculated using the Spearman rank test. RESULTS:No significant changes were observed in Group I. In Group P, epinephrine and norepinephrine increased in all patients during peritoneal insufflation and tumor resection. In 16 patients, systolic blood pressure, heart rate, low frequency, and LF/HF ratio increased concurrently. In four patients, low frequency and LF/HF ratio decreased. Three of these patients had normal systolic blood pressure and heart rate, and the fourth patient had hypotension and tachycardia. The high frequency component was enhanced in 15 patients and was stable in five. Low frequency was correlated with norepinephrine (r = 0.68, P < 0.001), systolic blood pressure (r = 0.66, P < 0.01), and heart rate (r = 0.62, P < 0.05). CONCLUSION:This study demonstrated a strong correlation between low frequency HRV, plasma norepinephrine, arterial blood pressure, and heart rate during pheochromocytoma surgery.

Spinal meningioma surgery in elderly patients with paraplegia or severe paraparesis: a multicenter study.

OBJECTIVEIn a multicenter study, 102 patients aged 70 years or older with paraplegia or severe paraparesis, and who underwent operation for spinal meningiomas, are presented to correlate surgery and outcome and to determine the most influential factors that affected this outcome. METHODSFive French neurosurgical centers participated in this retrospective study between 1990 and 2007. Pre- and postoperative neurological status were assessed using a grading system. All patients underwent operation, and neurological evaluations were conducted 3 months and 1 year after surgery. The median follow-up period was 49.5 months (range, 12–169 months). Data were analyzed using a multiple logistic regression model. RESULTSTwenty-six patients were paraplegic (Grade 4). Complete tumor removal was obtained in 93 patients. There was no surgical mortality, and morbidity was 9%. Three months after surgery, 7 of the patients were unchanged, 87 patients had improved, and 8 were not evaluated. One year after surgery, 7 of the 100 surviving patients were clinically unchanged and 93 had improved. Of those who had improved, 49 patients experienced complete recovery. CONCLUSIONAdvanced age did not seem to contraindicate surgery, even in patients with severe preoperative neurological deficits and/or an American Society of Anesthesiologists class of III. Quality of life can be improved in most cases.