Risk Factors for Malfunction of Ventriculoperitoneal Shunts Performed by Medical Residents in Children: An Exploratory Study / Fatores de risco para disfunção de derivações ventrículo-peritoneais realizadas por médicos residentes em crianças: Estudo exploratório

Introduction Ventriculoperitoneal shunts (VPSs) are common neurosurgical procedures, and in educational centers, they are often performed by residents. However, shunts have high rates of malfunction due to obstruction and infection, especially in pediatric patients. Monitoring the outcomes of shunts performed by trainee neurosurgeons is important to incorporate optimal practices and avoid complications. Methods In the present study, we analyzed the malfunction rates of VPSs performed in children by residents as well as the risk factors for shunt malfunction. Results The study included 37 patients aged between 0 and 1.93 years old at the time of surgery. Congenital hydrocephalus was observed in 70.3% of the patients, while 29.7% showed acquired hydrocephalus. The malfunction rate was 54.1%, and the median time to dysfunction was 28 days. Infections occurred in 16.2% of the cases. Cerebrospinal fluid leukocyte number and glucose content sampled at the time of shunt insertion were significantly different between the groups (p » 0.013 and p » 0.007, respectively), but did not have a predictive value for shunt malfunction. In a multivariate analysis, the etiology of hydrocephalus (acquired) and the academic semester (1st) in which the surgery was performed were independently associated with lower shunt survival (p » 0.009 and p » 0.026, respectively). Conclusion Ventriculoperitoneal shunts performed in children by medical residents were at a higher risk of malfunction depending on the etiology of hydrocephalus and the academic semester in which the surgery was performed.

Introdução As derivações ventrículo-peritoneais (DVPs) são procedimentos neurocirúrgicos comuns e, em centros educacionais, muitas vezes são realizados por residentes. No entanto, os shunts apresentam altas taxas de mau funcionamento devido a obstrução e infecção, especialmente em pacientes pediátricos. O monitoramento dos resultados das válvulas realizadas por neurocirurgiões em treinamento é importante para incorporar as práticas ideais e evitar complicações. Métodos No presente estudo, analisamos as taxas de mau funcionamento de DVPs realizados em crianças por residentes, assim como os fatores de risco para mau funcionamento da válvula. Resultados O estudo incluiu 37 pacientes com idades entre 0 e 1,93 anos na época da cirurgia. Hidrocefalia congênita foi observada em 70,3% dos pacientes, enquanto 29,7% apresentaram hidrocefalia adquirida. A taxa de disfunção foi de 54,1% e o tempo médio para disfunção foi de 28 dias. Infecções ocorreram em 16,2% dos casos. O número de leucócitos do líquido cefalorraquidiano e o conteúdo de glicose coletados no momento da inserção da válvula foram significativamente diferentes entre os grupos (p » 0,013 e p » 0,007, respectivamente), mas não tiveram um valor preditivo para o mau funcionamento da válvula. Em uma análise multivariada, a etiologia da hidrocefalia (adquirida) e o semestre letivo (1°) em que a cirurgia foi realizada foram independentemente associados a menor sobrevida do shunt (p » 0,009 e p » 0,026, respectivamente). Conclusão: Derivações ventrículo-peritoneais realizadas em crianças por médicos residentes apresentaram maior risco de mau funcionamento dependendo da etiologia da hidrocefalia e do semestre letivo no qual a cirurgia foi realizada.

Infecciones del sistema nervioso central asociadas a dispositivos de derivación de LCR en niños, en un centro neuro-quirúrgico de referencia nacional / Central nervous system infections associated with CSF shunt devices in children, at a national reference hospital

INTRODUCCIÓN: Las infecciones asociadas a dispositivos de derivación de LCR son una complicación frecuente en su utilización. Lo más habitual es la presencia de cocáceas grampositivas, como Staphylococcus coagulasa negativa (50% en algunas series) y Staphylococcus aureus. Esta complicación agrega morbimortalidad al paciente neuroquirúrgico, aumentando la estadía hospitalaria y los costos de tratamiento. OBJETIVO: Conocer la incidencia de infecciones asociadas a dispositivos de derivación de LCR en un centro de referencia nacional. METODOLOGÍA: Estudio descriptivo, retrospectivo. Se recolectó la información de los pacientes pediátricos (bajo 18 años) entre 2018 y 2019. Se realizó un análisis estadístico descriptivo e inferencial utilizando el lenguaje estadístico R 3.4.0 y RStudio 1.3.9. Se calculó la incidencia acumulada para cada procedimiento, evaluando si existe diferencias significativas entre ellas. Estudio aprobado por el Comité de Ética Pediátrico del SSMO. RESULTADOS: En el período estudiado se realizaron 175 cirugías. Encontramos 19 casos de ventriculitis asociada a derivativa ventriculo-peritoneal y 7 casos en derivativa ventricular-externa. Los agentes más frecuentes fueron las cocáceas grampositivas. No se logró identificar factores de riesgo significativos.

BACKGROUND: Infections associated with CSF shunt devices are a frequent complication in their use. The most common is the presence of gram positive coccaceae, such as coagulase negative Staphylococcus (50% in some series) and Staphylococcus aureus. This complication adds morbidity and mortality to the neurosurgical patient, increasing hospital stay and treatment costs. AIM: To determine the incidence of infections associated with CSF shunt devices in a national referral center. METHODS: Retrospective, descriptive study. Information was collected on pediatric patients between 2018 and 2019. A descriptive and inferential statistical analysis was performed using the statistical language R 3.4.0 and RStudio 1.3.9. The cumulative incidence for each procedure was calculated, evaluating whether there were significant differences between them. This study was approved by the Pediatric Ethics Committee of the SSMO. RESULTS: In the period studied, 175 surgeries were performed. We found 19 cases of ventriculitis associated with ventriculoperitoneal derivative and 7 cases in ventricular-external derivative. The most frequent agents were grampositive coccaceae. It was not possible to identify significant risk factors.

High Intra-Abdominal Pressure Secondary to Obesity as a Determining Factor for Ventriculoperitoneal Shunt Malfunction

The ventriculoperitoneal shunt (VPS) is an established treatment for hydrocephalus. The functioning of the system requires a pressure difference between the cranial and abdominal cavities. The VPS can be particularly problematic in patients with increased intra-abdominal pressure (IAP). We report the case of a 16-year-old girl with VPS since she was 2 months old due to hydrocephalus secondary to myelomeningocele. The patient had been asymptomatic ever since, but she sought the emergency service with intermittent headache and vomiting. A non-enhanced brain tomography, a shunt trajectory X-ray and an abdominal ultrasound revealed no cause of system malfunction. In view of the persistent clinical picture, a revision of the shunt was performed, which revealed adequate intraoperative functioning. She returned with the same symptoms two weeks after surgery. The patient was obese (body mass index [BMI]: 48). We hypothesized intermittent valve malfunction due to increased intra-abdominal pressure. She underwent a ventriculoatrial shunt, without intercurrences. In the postoperative period, the patient presented transient tachycardia and was asymptomatic at the 6-month follow-up. Obesity should be considered an important variable for the inadequate functioning of the VPS due to increased IAP and catheter dystocia to the extraperitoneal cavity. Studies have already correlated the IAP with the BMI, which reaches between 8 mm Hg and 12 mm Hg in obese individuals. Therefore, the BMI can be considered during the selection of valve pressure in systems with non-adjustable valves to prevent insufficient drainage. The recognition of obesity as a cause of VPS malfunction is fundamental to avoid unnecessary surgeries and intermittent malfunction of the system.

A derivação ventriculoperitoneal (DVP) é um tratamento estabelecido para a hidrocefalia; contudo, algumas variáveis podem influenciar na eficácia desta modalidade. O funcionamento do sistema requer uma diferença de pressão entre as cavidades craniana e abdominal. A DVP pode ser particularmente problemática em pacientes com aumento da pressão intra-abdominal (PIA). Neste artigo, relatamos o caso de uma paciente do sexo feminino, de 16 anos, portadora de DVP desde os 2 meses de idade por hidrocefalia secundária a mielomeningocele. Desde então assintomática, procurou o pronto-socorro com queixa de cefaleia e vômitos intermitentes. Uma tomografia de crânio sem contraste, um raio X (RX) do trajeto do cateter distal, e uma ultrassonografia (USG) abdominal não evidenciaram a causa do mau funcionamento do sistema. Diante do quadro persistente, realizou-se uma revisão da derivação, que mostrou funcionamento adequado no período intraoperatório. A paciente retornou com os mesmos sintomas duas semanas após a cirurgia. A paciente era obesa (índice de massa corporal [IMC]: 48). Aventou-se possível funcionamento intermitente da válvula pelo aumento da PIA. A paciente foi submetida a uma derivação ventrículo-atrial, que foi realizada sem intercorrências. No pós-operatório, ela apresentou quadro transitório de taquicardia, e não apresentou sintomas no acompanhamento feito depois de 6 meses. A obesidade deve ser considerada uma variável importante para o funcionamento inadequado da DVP, pelo aumento da PIA e pela associação com distocia do cateter para a cavidade extraperitoneal. Estudos já correlacionaram a PIA com o IMC, que pode atingir entre8 mm Hg e 12 mm Hg em obesos. Logo, o IMC pode ser considerado na seleção da pressão da válvula em sistemas com válvulas não ajustáveis, para prevenir a drenagem insuficiente. O reconhecimento da obesidade de risco para o mau funcionamento da DVP é fundamental para evitar cirurgias desnecessárias e o mau funcionamento intermitente do sistema.

Cerebrospinal Fluid Lumbar Tapping Utilization for Suspected Ventriculoperitoneal Shunt Under-Drainage Malfunctions

OBJECTIVE: The diagnosis of shunt malfunction can be challenging since neuroimaging results are not always correlated with clinical outcomes. The purpose of this study was to evaluate the efficacy of a simple, minimally invasive cerebrospinal fluid (CSF) lumbar tapping test that predicts shunt under-drainage in hydrocephalus patients. METHODS: We retrospectively reviewed the clinical and radiological features of 48 patients who underwent routine CSF lumbar tapping after ventriculoperitoneal shunt (VPS) operation using a programmable shunting device. We compared shunt valve opening pressure and CSF lumbar tapping pressure to check under-drainage. RESULTS: The mean pressure difference between valve opening pressure and CSF lumbar tapping pressure of all patients were 2.21±24.57 mmH₂O. The frequency of CSF lumbar tapping was 2.06±1.26 times. Eighty five times lumbar tapping of 41 patients showed that their VPS function was normal which was consistent with clinical improvement and decreased ventricle size on computed tomography scan. The mean pressure difference in these patients was −3.69±19.20 mmH₂O. The mean frequency of CSF lumbar tapping was 2.07±1.25 times. Fourteen cases of 10 patients revealed suspected VPS malfunction which were consistent with radiological results and clinical symptoms, defined as changes in ventricle size and no clinical improvement. The mean pressure difference was 38.07±23.58 mmH₂O. The mean frequency of CSF lumbar tapping was 1.44±1.01 times. Pressure difference greater than 35 mmH₂O was shown in 2.35% of the normal VPS function group (2 of 85) whereas it was shown in 64.29% of the suspected VPS malfunction group (9 of 14). The difference was statistically significant (p=0.000001). Among 10 patients with under-drainage, 5 patients underwent shunt revision. The causes of the shunt malfunction included 3 cases of proximal occlusion and 2 cases of distal obstruction and valve malfunction. CONCLUSION: Under-drainage of CSF should be suspected if CSF lumbar tapping pressure is 35 mmH₂O higher than the valve opening pressure and shunt malfunction evaluation or adjustment of the valve opening pressure should be made.

Acute Shunt Malfunction Caused by Percutaneous Endoscopic Gastrostomy without Shunt Infection

Percutaneous endoscopic gastrostomy tube placement is often performed in patients with a ventriculoperitoneal shunt and it has been accepted as a safe procedure. The authors report a case of a 50-year-old male who developed acute exacerbation of the hydrocephalus immediately after the percutaneous endoscopic gastrostomy tube placement without any signs of shunt infection, which has not been reported until now. After revision of the intraperitoneal shunt catheter, the sizes of the intracranial ventricles were normalized.

Asymptomatic Fracture of a Distal Shunt Catheter after Ventriculoperitoneal Shunt for Post-traumatic Hydrocephalus / 대한소아신경학회지

A fracture of a distal shunt catheter is a rare complication. In many cases of shunt failure, shunt revision should be performed to prevent the development of hydrocephalus. However, the question of whether to operate on asymptomatic patients remains to be answered. Our patient received a ventriculoperitoneal shunt due to post-traumatic hydrocephalus, and his symptoms improved. Abdominal x-ray revealed a fracture of the distal shunt catheter at the 5- year follow-up. However, the patient was asymptomatic. In this case, the patient improved without shunt revision during the year after the fracture of the distal shunt catheter.

Does CSF composition predict shunt malfunction in Tuberculous Meningitis.

Background: Hydrocephalus secondary to tuberculous meningitis (TBM) continues to be a challenging condition to treat for neurosurgeons in developing countries. Shunt complications are reportedly more frequent in patients undergoing ventriculo-peritoneal shunt in patients with TBM than in those undergoing shunt surgeries for other causes. Aim: The aim of this study was to evaluate the relationship of cerebrospinal fluid (CSF) composition on shunt malfunction. Methods: We compared the CSF composition of 53 patients who had shunt malfunction during a five year period with that of 137 matched controls. Results: Patients who had shunt malfunction had a significantly higher concentration of CSF protein. The CSF cellularity and glucose concentration did not have any significant bearing in predicting shunt malfunction. Patients with CSF protein concentration of more than 200 mg/dL had a four times higher risk of having shunt malfunction than those with a concentration of less than 100 mg/dL. Patients with CSF protein in the 100-200 mg/dL range represent an intermediate zone. Conclusion: To conclude, patients with CSF protein concentration of more than 200 mg/dL have a significantly higher risk of shunt malfunction and hence have to be followed up closely.

Rostral Midbrain Dysfunction Associated with Hydrocephalus Secondary to Periaqueductal Tumor

The authors report a case of rostral mesencephalic dysfunction due to obstructive hydrocephalus secondary to periaqueductal tumor who suffered multiple shunt failures and shunt revision. This patient presented with clinical syndromes, including akinetic mutism and diencephalic autonomic epilepsy. He had computed tomography(CT) and magnetic resonance(MR) findings of dilatation of ventricular system with periaqueductal tumor. The anatomical substrates of clinical findings are reviewed. A discussion of the probable mechanism proposes that dilatation of 3rd ventricle and rostral aqueduct sufficiently explains the entire syndrome.

Porencephalic Cyst Associated with Shunt Malfunction

When hydrocephalus develops, excessive cerebrospinal fluid accumulation usually occurs within the ventricular system, leading to a ventriculomegaly caused by increased intracranial pressure. Shunt malfunction, a common complication after a shunt operation, usually occurs, together with recurring ventricular dilatation. The authors report a case of shunt malfunction which manifested as a porencephalic cyst along the proximal catheter. The cyst subsided after the replacement of the shunt system, and this led to the patient's clinical improvement. We postulate that although the region around a catheter is an unusual site for cerebrospinal fluid collection, this finding should be considered as a shunt obstruction. The possible mechanism of reversible porencephaly is discussed and the literature is briefly reviewed.

Ventriculoureteral Shunt Operation for Treatment of Recurrent Abdominal Pseudocyst Complicating Ventriculoperitoneal Shunt: Case Report and Technical Note

We report a case of ventriculoureteral shunt to reise malfunctioning ventriculoperitoneal shunt in a 30-year-old man. The patient had 4 times recurrent pseudocyst filled with cerebrospinal fluid caused by complications at the distal end of the abdominal catheter. The presence of an abdominal pseudocyst can be detected by performing an ultrasound examination of the abdomen. We shall describe the operative technique of the ventriculoureteral shunt procedure without nephrectomy by reimplantation of the ureter and a psoas hitch.

A Clinical Analysis of Ventriculoperitoneal Shunt

The author analyzed 73 patients with hydrocephalus, who were managed by ventriculoperitoneal shunt in recent 5 years at Chung-Ang University Hospital. The causes of hydrocephalus were brain tumor(23%), head trauma(21%), aqueductal stenosis(16%), myelomeningocele(4%), spontaneous subarachnoid hemorrhage (14%), meningitis(12%) and idiopathic normal pressure hydrocephalus(10%). Their symptoms and signs were gait disturbance(39 patients), mental change(31 patients), papilledema(30 patients) and urinary incontinence(20 patients). Gait disturbance of 39 patients was improved in 23 patients(59%), but visual acuity was improved in only 1 patient. The brain computed tomography showed "roundness" of frontal horns(100%), moderate ventricular dilatation(61%), obliteration of cerebral sulci(68%) and periventricular low densities(56% ). Accu-Flo distal slit valve system was applied in all cases and medium pressure valve(closing pressure: 5-9 cm H20) was selected in 65 patients. Twenty reoperations were done in 16 patients and their causes were shunt malfunction(13 cases) and infection(4 cases) . Ventricular puncture was done through the Keen's point in all cases and ventricular catheter tip was inserted into the contralateral frontal horn in 30 cases, but there was no shunt malfunction in those patients.

Shunt Complications

There had been a lot of changes and advances in treatment of hydrocephalus. Many efforts also had been made to prevent complication of shunting, but there are a lot of inevitable problems in shunting operation. This paper attemps to review and summarize these shunt complications.

Ventriculoperitoneal Shunt Malfunction during Pregnancy

A 24 year-old woman with a ventriculoperitoneal shunt is presented, who showed repeated episodes of shunt malfunction before and during pregnancy. Daily pumping of the flushing device relieved the symptoms at first, but reattack during the third trimester of pregnancy was managed with revision of the shunt to ventriculoatrial system. She delivered a healthy female baby successfully at term.