Evaluating the cerebrospinal fluid tap test with the Hellström iNPH scale for patients with idiopathic normal pressure hydrocephalus.

BACKGROUND: The cerebrospinal fluid tap test (CSF TT) is used for selecting shunt surgery candidates among patients with idiopathic normal pressure hydrocephalus (iNPH). We aimed to evaluate the predictive value of the CSF TT, by using the Hellström iNPH scale for shunted iNPH patients with a standardized method. METHODS: One hundred and sixteen shunt-operated iNPH patients were retrospectively included in this study. The gait and balance domains in the iNPH scale were used as outcome measures for the CSF TT and the total iNPH scale score as the postoperative outcome. A positive response to CSF TT was defined as a change of ≥ 5 points in the gait domain and ≥ 16 points in the balance domain. Differences between CSF TT responders and non-responders, sensitivity, specificity, positive and negative predictive values, accuracy, and correlations between changes from baseline to post CSF TT and from baseline to the postoperative follow-up, were calculated. RESULTS: In the CSF TT there were 63.8% responders in the gait domain and correspondingly 44.3% in the balance domain. CSF TT responders had a significantly better postoperative outcome in the total scale score (gait P ≤ 0.001, balance P ≤ 0.012) and gait CSF TT responders improved more in gait (P ≤ 0.001) and balance CSF TT responders in balance (P ≤ 0.001). No differences between CSF TT gait or balance responders could be found in neuropsychological or urinary continence assessments postoperatively. The sensitivity and specificity of the CSF TT and the outcome of the total iNPH scale score postoperatively were 68.1% and 52.0% for gait and 47.8% and 68.0% for balance, respectively. CONCLUSIONS: The CSF TT, with the Hellström iNPH scale as the outcome measure, has clear limitations in predicting postoperative results. The gait domain may be used to predict outcomes for gait, but the balance domain is too insensitive.

The effect of needle size on cerebrospinal fluid collection time and post-dural puncture headache: A retrospective cohort study.

OBJECTIVE: The main objective of this study was to compare cerebrospinal fluid (CSF) collection time and patient's discomfort between 20G (a)traumatic and 22G atraumatic needles. BACKGROUND: Risk of post-dural puncture headache (PDPH) is decreased using atraumatic needles. Smaller needles may give lower risk but possibly at the cost of increased CSF collection time (due to lower flow), leading to additional patient's discomfort. METHODS: We performed a retrospective study of lumbar puncture data from a research program on CSF metabolomics and compared traumatic 20G (n = 210) with atraumatic 20G (n = 39) and 22G (n = 105) needles. In this cohort, incidence of PDPH was prospectively registered with other procedure details. Primary outcome was CSF collection time (time to fill the tube). Secondary outcomes were pain and stress scores during procedure, and incidence of PDPH. RESULTS: The time to collect 10 mL of CSF was longer for 22G needles (6.1 minutes; 95% CI 5.8-6.5) than for 20G traumatic (2.2 minutes; 95% CI 2.1-2.2) and 20G atraumatic needles (2.9 minutes; 95% CI 2.8-3.1). There were no differences in pain and stress scores. PDPH was lower for 22G atraumatic needles: odds ratio 0.41 (95% CI 0.25-0.66) versus 20G traumatic needles and 0.53 (95% CI 0.40-0.69) versus 20G atraumatic needles. Absolute PDPH rates were 69/210 (32.9%) for 20G traumatic, 13/39 (33.3%) for 20G atraumatic, and 19/105 (18.1%) for 22G atraumatic needles. CONCLUSIONS: CSF collection time is slightly longer for smaller 22G needles, but this does not lead to more discomfort for the patient.

Neonates With Urinary Tract Infection: Is a Lumbar Puncture Always Indicated?

BACKGROUND: Our objectives were to determine the prevalence of and to identify risk factors for coexisting bacterial meningitis (BM) in neonates with urinary tract infection (UTI). METHODS: A cross-sectional study was conducted at pediatric emergency department of a tertiary teaching hospital from 2001 to 2017. Infants <29 days of age with UTI (≥10,000 colony-forming units/mL of a single pathogen from a catheterized specimen in association with positive urinalysis) were included. Definite BM was defined as growth of a single bacterial pathogen from a cerebrospinal fluid (CSF) sample and probable BM as (1) positive blood culture with CSF pleocytosis and treatment consistent with BM or (2) antibiotic pretreatment before lumbar puncture, CSF pleocytosis and treatment consistent with BM. Univariate testing was used to identify possible risk factors associated with BM. Receiver operating characteristics curves were constructed for the laboratory markers associated with BM. RESULTS: Three hundred seventy-one infants were included. Five [1.3%; 95% confidence interval (CI): 0.6%-3.1%] had BM: 4 definite BM and 1 probable BM. Risk factors detected for BM were classified as not being well-appearing and a procalcitonin value ≥0.35 ng/mL [sensitivity of 100% (95% CI: 56.6%-100%) and negative predictive value of 100% (95% CI: 96.1%-100%)]. CONCLUSIONS: Coexisting BM occurs uncommonly in neonates with UTI. Well-appearing neonates with UTI and procalcitonin value <0.35 ng/mL were at very low risk for BM; avoiding routine lumbar puncture in these patients should be considered.

Ventriculo-peritoneal shunting is a safe and effective treatment for idiopathic intracranial hypertension.

PURPOSE: To determine the outcome of ventriculo-peritoneal shunts as a treatment for idiopathic intracranial hypertension (IIH) Materials and Methods: Retrospective case series of 28 patients with IIH and evidence of raised intracranial pressure (ICP) who underwent shunt insertion. Patients were identified from a prospectively updated operative database. A case-notes review was performed and data on type of shunt, pre- and post-operative symptoms, ophthalmological findings and post-operative complications were recorded. RESULTS: All patients had symptoms of IIH that had failed medical management. Twelve patients had previous lumbo-peritoneal shunts and 2 patients had previous venous sinus stents. All patients had evidence of raised ICP as papilloedema and raised CSF pressure on lumbar puncture. Twenty-seven patients received a ventriculo-peritoneal shunt and 1 patient a ventriculo-atrial shunt. Twenty-six patients received Orbis Sigma Valves and 2 patients Strata valves. At follow-up all patients (100%) had improvement/resolution of papilloedema, 93% had improved visual acuity and 84% had improved headaches. Mean time to last follow-up was 15 (range 4-96) months. Complications occurred in 3 patients (11%): 2 patients required revision of their peritoneal catheters and 1 patient had an anti-siphon device inserted. CONCLUSIONS: Previous literature reported a ventricular shunt revision rate of 22-42% in the management of IIH. We demonstrate ventriculo-peritoneal shunts to be an effective treatment with a revision rate of 11% compared to the previously reported 22-42%.

Disease duration: the key to accurate CSF tap test in iNPH.

OBJECTIVES: The cerebrospinal fluid tap test for idiopathic normal pressure hydrocephalus (iNPH) is one of the good predictors of the shunt treatment, although this test has a low sensitivity. We aimed to identify key parameters that could be used to improve this sensitivity. MATERIALS & METHODS: During 2010-2011, we recruited and then followed 93 patients with possible iNPH for 12 months after shunt. Among them, 82 patients were finally enrolled in this study. The modified Rankin Scale, iNPH grading scale, and several quantitative measurements were evaluated at entry, after the tap test, before and after shunt. Area under the receiver-operating characteristic curves (AUCs), sensitivities, and specificities of the tap test for predicting shunt effectiveness were calculated for each measurement. They were additionally assessed after stratification by disease duration since the initial presentation of iNPH symptoms. RESULTS: The gait disturbance on the iNPH grading scale had the highest accurate scale at the tap test for predicting effectiveness 12 months after shunt: AUC 0.74, sensitivity 56.5%, specificity 91.7%. This AUC increased to 0.76, 0.91 and 0.94 in the subgroup of disease duration <24, <12, and <6 months, respectively. The sensitivity and specificity of the gait disturbance on the iNPH grading scale in the subgroup of <12 months' duration were 92.3% and 90.0%. CONCLUSIONS: The shorter period of clinical symptoms, for example, <12 months, made the tap test sufficiently accurate examination for predicting improvement 12 months after shunt surgery. The findings imply that the tap test should be applied to patients being considered for shunt surgery as soon as possible.

Determination of a Testing Threshold for Lumbar Puncture in the Diagnosis of Subarachnoid Hemorrhage after a Negative Head Computed Tomography: A Decision Analysis.

OBJECTIVE: The objective was to determine the testing threshold for lumbar puncture (LP) in the evaluation of aneurysmal subarachnoid hemorrhage (SAH) after a negative head computed tomography (CT). As a secondary aim we sought to identify clinical variables that have the greatest impact on this threshold. METHODS: A decision analytic model was developed to estimate the testing threshold for patients with normal neurologic findings, being evaluated for SAH, after a negative CT of the head. The testing threshold was calculated as the pretest probability of disease where the two strategies (LP or no LP) are balanced in terms of quality-adjusted life-years. Two-way and probabilistic sensitivity analyses (PSAs) were performed. RESULTS: For the base-case scenario the testing threshold for performing an LP after negative head CT was 4.3%. Results for the two-way sensitivity analyses demonstrated that the test threshold ranged from 1.9% to 15.6%, dominated by the uncertainty in the probability of death from initial missed SAH. In the PSA the mean testing threshold was 4.3% (95% confidence interval = 1.4% to 9.3%). Other significant variables in the model included probability of aneurysmal versus nonaneurysmal SAH after negative head CT, probability of long-term morbidity from initial missed SAH, and probability of renal failure from contrast-induced nephropathy. CONCLUSIONS: Our decision analysis results suggest a testing threshold for LP after negative CT to be approximately 4.3%, with a range of 1.4% to 9.3% on robust PSA. In light of these data, and considering the low probability of aneurysmal SAH after a negative CT, classical teaching and current guidelines addressing testing for SAH should be revisited.

Use of an error-focused checklist to identify incompetence in lumbar puncture performances.

CONTEXT: Checklists are commonly used in the assessment of procedural competence. However, on most checklists, high scores are often unable to rule out incompetence as the commission of a few serious procedural errors typically results in only a minimal reduction in performance score. We hypothesised that checklists constructed based on procedural errors may be better at identifying incompetence. OBJECTIVES: This study sought to compare the efficacy of an error-focused checklist and a conventionally constructed checklist in identifying procedural incompetence. METHODS: We constructed a 15-item error-focused checklist for lumbar puncture (LP) based on input from 13 experts in four Canadian academic centres, using a modified Delphi approach, over three rounds of survey. Ratings of 18 video-recorded performances of LP on simulators using the error-focused tool were compared with ratings obtained using a published conventional 21-item checklist. Competence/incompetence decisions were based on global assessment. Diagnostic accuracy was estimated using the area under the curve (AUC) in receiver operating characteristic analyses. RESULTS: The accuracy of the conventional checklist in identifying incompetence was low (AUC 0.11, 95% confidence interval [CI] 0.00-0.28) in comparison with that of the error-focused checklist (AUC 0.85, 95% CI 0.67-1.00). The internal consistency of the error-focused checklist was lower than that of the conventional checklist (α = 0.35 and α = 0.79, respectively). The inter-rater reliability of both tools was high (conventional checklist: intraclass correlation coefficient [ICC] 0.99, 95% CI 0.98-1.00; error-focused checklist: ICC 0.92, 95% CI 0.68-0.98). CONCLUSIONS: Despite higher internal consistency and inter-rater reliability, the conventional checklist was less accurate at identifying procedural incompetence. For assessments in which it is important to identify procedural incompetence, we recommend the use of an error-focused checklist.

Reduction of contractility and reactivity in isolated lymphatics from hemorrhagic shock rats with resuscitation

PURPOSE: To evaluate the changes of contractility and reactivity in isolated lymphatics from hemorrhagic shock rats with resuscitation. METHODS: Six rats in the shock group suffered hypotension for 90 min by hemorrhage, and resuscitation with shed blood and equal ringer's solution. Then, the contractility of lymphatics, obtained from thoracic ducts in rats of the shock and sham groups, were evaluated with an isolated lymphatic perfusion system using the indices of contractile frequency (CF), tonic index (TI), contractile amplitude (CA) and fractional pump flow (FPF). The lymphatic reactivity to substance P (SP) was evaluated with the different volume of CF, CA, TI and FPF between pre- and post-treatment of SP at different concentrations. RESULTS: The CF, FPF, and TI of lymphatics obtained from the shocked rats were significantly decreased than that of the sham group. After SP stimulation, the ∆CF (1×10-8, 3×10-8, 1×10-7, 3×10-7 mol/L), ∆FPF (1×10-8, 3×10-8, 1×10-7 mol/L), and ∆TI (1×10-8 mol/L) of lymphatics in the shock group were also obviously lower compared with the sham group. In addition, there were no statistical differences in CA and ∆CA between two groups. CONCLUSION: Lymphatic contractility and reactivity to substance P appears reduction following hemorrhagic shock with resuscitation. .

Idiopathic intracranial hypertension: Clinical nosography and field-testing of the ICHD diagnostic criteria. A case-control study.

AIMS: The aims of this article are to characterize the headache in idiopathic intracranial hypertension (IIH) and to field-test the ICHD diagnostic criteria for headache attributed to IIH. MATERIALS AND METHODS: We included 44 patients with new-onset IIH. Thirty-four patients with suspected but unconfirmed IIH served as controls. Headache and other IIH-related symptoms were assessed by a detailed standardized interview. In participants referred before diagnostic lumbar puncture (n = 67), we recorded headache intensity before and after cerebrospinal fluid (CSF) withdrawal. RESULTS: Headache in patients with IIH was daily occurring in 86%, focal in 84% and pulsating in 52%. Aggravation of headache by coughing or straining and relief after CSF withdrawal were significantly more frequent in patients than in controls (p ≤ 0.002). From the ICHD-2 to the ICHD-3 beta classification the sensitivity increased from 60% to 86% whereas the specificity decreased from 86% to 53%. Based on our data the headache criteria can be revised to increase sensitivity to 95% and specificity to 65%. CONCLUSION: Aggravation of headache by coughing or straining, relief after CSF withdrawal, retrobulbar pain and pulsatile tinnitus may suggest intracranial hypertension. Based on data from a well-defined IIH cohort, we propose a revision of the ICDH-3 beta diagnostic criteria with improved clinical applicability and increased sensitivity and specificity.

Navigated simulator for spinal needle interventions.

We present a navigated simulator for ultrasound-guided spine needle interventions, comprising of an ultrasound scanner, tracking system, surgical instruments, tissue-mimicking spine phantom, and augmented virtuality navigation platform. The ultrasound transducer, spine needle, and spine phantom are magnetically tracked and spatially calibrated, allowing the navigation software to render the surgical scene with streaming ultrasound video in 3D. The spine phantom provides sonoanatomically correct images, with realistic tactile sensation from needle advancement through tissues layers. The combination of a physical phantom and navigation software provides a realistic, inexpensive, and interactive environment for teaching and learning, the latter also having potential as an interventional tool for real-time ultrasound-guided spine needle insertion.

Fluoroscopic-guided lumbar puncture: fluoroscopic time and implications of body mass index--a baseline study.

BACKGROUND AND PURPOSE: Fluoroscopic-guided lumbar puncture is an effective alternative to bedside lumbar puncture in challenging patients. However, no published guidelines are available for an acceptable range of fluoroscopic time for this procedure. The purpose of this study was to set department benchmark fluoroscopic times for lumbar puncture, accounting for body mass index in our patient population. MATERIALS AND METHODS: We identified and reviewed all patients who underwent fluoroscopic-guided lumbar puncture at 4 hospitals during a 2-year period (July 2011 to June 2013). Data collection included patient information (demographics, body mass index, history of prior lumbar surgery and/or lumbar hardware, scoliosis); procedure details (fluoroscopic time, level of access, approach, needle gauge and length); level of operator experience; and hospital site. A generalized linear model was used to test whether body mass index influenced fluoroscopic time while controlling other factors. RESULTS: Five hundred eighty-four patients (mean age, 47.8 ± 16.2 years; range, 16-92 years; 33% male) had successful fluoroscopic-guided lumbar puncture s. Mean body mass index and fluoroscopic time were higher in female patients (34.4 ± 9.9 kg/m(2) and 1.07 minutes; 95% CI, 0.95-1.20) than in male patients (29.2 ± 7.3 kg/m(2) and 0.91 minutes; 95% CI, 0.79-1.03). Body mass index (P = .001), hospital site (P < .001), and level of experience (P = .03) were factors significantly affecting fluoroscopic time on multivariate analysis. Benchmark fluoroscopic times in minutes were the following: 0.48 (95% CI, 0.40-0.56) for normal, 0.61 for overweight (95% CI, 0.52-0.71), 0.63(95% CI, 0.58-0.73) for obese, and 0.86 (95% CI, 0.74-1.01) in extremely obese body mass index categories. CONCLUSIONS: In patients undergoing fluoroscopic-guided lumbar punctures, fluoroscopy time increased with body mass index We established benchmark fluoroscopic-guided lumbar puncture time ranges as related to body mass index in our patient population.

Overdrainage shunt complications in idiopathic normal-pressure hydrocephalus and lumbar puncture opening pressure.

OBJECT: Management of idiopathic normal-pressure hydrocephalus (iNPH) is hard because the diagnosis is difficult and shunt surgery has high complication rates. An important complication is overdrainage, which often can be treated with adjustable-shunt valve manipulations but also may result in the need for subdural hematoma evacuation. The authors evaluated shunt surgery overdrainage complications in iNPH and their relationship to lumbar puncture opening pressure (LPOP). METHODS: The authors reviewed the charts of 164 consecutive patients with iNPH who underwent shunt surgery at their institution from 2005 to 2011. They noted age, sex, presenting symptoms, symptom duration, hypertension, body mass index (BMI), imaging findings of atrophy, white matter changes, entrapped sulci, LPOP, valve opening pressure (VOP) setting, number of valve adjustments, serious overdrainage (subdural hematoma requiring surgery), radiological overdrainage (subdural hematomas or hygroma seen on postoperative imaging), clinical overdrainage (sustained or postural headache), other complications, and improvements in gait, urine control, and memory. RESULTS: Eight patients (5%) developed subdural hematomas requiring surgery. All had an LPOP of greater than 160 mm H2O and an LPOP-VOP of greater than 40 mm H2O. Radiological overdrainage was more common in those with an LPOP of greater than 160 mm H2O than in those with an LPOP of less than 160 mm H2O (38% vs. 21%, respectively; p = 0.024). The BMI was also significantly higher in those with an LPOP of greater than 160 mm H2O (median 30.2 vs. 27.0, respectively; p = 0.005). CONCLUSIONS: Serious overdrainage that caused subdural hematomas and also required surgery after shunting was related to LPOP and LPOP-VOP, which in turn were related to BMI. If this can be replicated, individuals with a high LPOP should have their VOP set close to the LPOP, or even higher. In doing this, perhaps overdrainage complications can be reduced.

Revised diagnostic criteria for the pseudotumor cerebri syndrome in adults and children.

The pseudotumor cerebri syndrome (PTCS) may be primary (idiopathic intracranial hypertension) or arise from an identifiable secondary cause. Characterization of typical neuroimaging abnormalities, clarification of normal opening pressure in children, and features distinguishing the syndrome of intracranial hypertension without papilledema from intracranial hypertension with papilledema have furthered our understanding of this disorder. We propose updated diagnostic criteria for PTCS to incorporate advances and insights into the disorder realized over the past 10 years.

Sedation of children during measurement of CSF opening pressure: lack of standardisation in German children with pseudotumor cerebri.

BACKGROUND: Diagnosis of pseudotumor cerebri (PTC) requires proper documentation of raised CSF opening-pressure. In childhood results may not be reliable due to insufficient sedation/analgesia or drug effects. We aimed to evaluate the current practice regarding pain and stress management in children undergoing lumbar puncture (LP) for pressure measurement. METHODS: A one-year survey was conducted involving 368 German paediatric departments. All children with newly diagnosed PTC should be reported. Details analyzed here included: age, sex, CSF opening pressure and type of procedural sedation and analgesia (PSA) during LP. RESULTS: 61 patients were analyzed, aged 6 months to 17 years. 29 patients (47%) did not receive any kind of PSA. In children receiving PSA the following regimens were used: Ketamine; Midazolam; Ketamine + Midazolam; Midazolam + Piritramide; Propofol; Profofol + Midazolam; general anaesthesia. CONCLUSION: Pain and stress management in children undergoing LP for CSF opening pressure measurement is often insufficient. Pain, stress and the variability of PSA regimen may be confounders of pressure measurement. In order to prevent false diagnoses of PTC and to obtain comparable results at different centers, a general consensus on PSA in children undergoing LP for CSF opening pressure measurements is required.

The safe use of spinal drains in thoracic aortic surgery.

Paraplegia is a devastating complication which may occur following surgery on the thoracic aorta. The use of a cerebrospinal fluid drain (CSFD) has helped reduce the incidence of neurological deficit; however, the management of patients with a CSFD postsurgery requires nurses and doctors to have expertise and awareness of the associated complications. The National Patient Safety Agency (UK) has highlighted a number of cases involving inadvertent spinal injections throughout the UK National Health Service (NHS). To this end we have introduced a protocol or 'care bundle' for safe CSFD care as well as drain management. The protocol was developed by medical and nursing staff at our institution based on clinical experience and literature reviews over a two-year period (2008-2010). Interventions undertaken during the development of the protocol included discussion with the UK National Patient Safety Agency (NPSA). Content of the protocol was reviewed by internal regulatory bodies within the hospital prior to ratification and general dissemination. Clear guidance is given within the policy on the standards expected when caring for the line and managing drainage according to agreed parameters of spinal cord perfusion pressure. The protocol constitutes five documents which guide staff in the care of CSFD, its routine management, documentation and interventions necessary once neurological deficit is detected. Document 1 which is a checklist, communication tool and aide-memoire was developed to ensure effective management, when the patient arrives in intensive care unit (ICU) from theatre. Document 2 ensures that early detection of a neurological deficit is noted and with Document 3 is acted upon immediately to reverse the injury. Document 4 provides information on the safe administration of analgesia via the spinal drain and has reference to the Glasgow Coma Scale. Document 5 is a bespoke observation chart for documenting CSFD pressure and cerebrospinal fluid drainage. In conclusion, the protocol acts as a guide for safe management of the CSFD and directs staff in reacting to detection of neurological deficit.

Bone marrow aspirations and lumbar punctures in retinoblastoma at diagnosis: correlation with IRSS staging.

BACKGROUND: Few studies have suggested that routine bone marrow (BM) and cerebrospinal fluid (CSF) evaluation is not needed in all patients with retinoblastoma. Although the International Retinoblastoma Staging System was developed recently, there remain no clear stage-specific guidelines with regard to the need for BM and CSF evaluations as part of the metastatic workup for patients with retinoblastoma. METHODS: This is a retrospective study analyzing results of CSF cytology and BM evaluation at presentation/diagnosis in patients with retinoblastoma registered at our center from June, 2003 to June, 2009. Only cases with both BM biopsy and lumbar puncture were included. RESULTS: Of the 259 evaluable patients, 18 (7%) were positive for metastasis either in CSF and/or BM. Although 7 of these had overt metastasis at presentation (stage IV), 1 belonged to stage II and 10 to stage IIIa. No stage 0 or I patient tested positive despite presence of histopathologic high-risk factors. CONCLUSIONS: This is the largest study evaluating the role of metastatic workup in patients with retinoblastoma at presentation. We conclude that CSF and BM evaluation is not required in patients with stage 0 and I retinoblastoma at presentation. No definitive recommendation could be made for stage II patients; while stage III and IV patients must certainly be evaluated.

[Evaluation of trainee doctors' skills]. / Evaluering af yngre laegers faerdigheder.

The objective was to perform a needs assessment of trainee doctors' competences within lumbar puncture and bone marrow aspiration in paediatric oncology. Audit of 30 medical records revealed that five procedures, i.e. collegial, supervised administration of chemotherapy, examination of the child, length of bone marrow biopsy, erythrocytes in cerebrospinal fluid, and documentation of procedures in the medical record, were only handled as intended in half of the cases. Education and supervision of trainee doctors should be prioritized in order to increase their competences and decrease the risk of critical incidents.