Risk of ventriculoperitoneal shunt infections due to gastrostomy feeding tube insertion in pediatric patients with brain tumors

OBJECTIVE: To determine the risk of ventriculoperitoneal (VP) shunt infections after percutaneous retrograde gastrostomy feeding tube (GT) placement in children with brain tumors. PATIENTS AND METHODS: All children (age 0-18 years) with primary brain tumors diagnosed and treated at the Hospital for Sick Children, Toronto, Canada, were subjected to a retrospective analysis. Two groups were identified: the study group included children with a VP shunt and a GT; the control group included children with VP shunts only. Each study patient was matched with 2 controls to compare the rate of infections (cohort comparative study). RESULTS: There were 1,167 children diagnosed and treated with primary brain tumors during the study period (1988-2003); 174 (15%) had a VP shunt and 23 (2%) children had both, a VP shunt and a GT. In the study group (n=17), GTs were inserted at a median time of 80 days (range 6-204 days) after VP shunts. VP shunt infection rate was 23.5% (4/17) compared to 8.8% (3/34) in the control group (OR 3.18; 95% CI 0.622-16.54, p=0.16). Three (75%) of the infection episodes in the study group presented with an ascending VP shunt infection directly related to the GT insertion or manipulation in the first 6 weeks. These GTs were inserted at 13, 47 and 49 days after VP shunt insertion. CONCLUSION: Placement of percutaneous retrograde GTs, in the acute phase, in children with brain tumors and VP shunts may increase the risk of ascending meningitis especially if there are early GT-related complications.     

Cerebrospinal fluid shunt infections in children

Forty-six episodes of cerebrospinal fluid shunt infections developed in 32 patients undergoing cerebrospinal fluid shunt operations during a 13-year period (1972 to 1984). The infection rate was 21%/operative procedure and 33%/patient. The shunt infection rate in revisions of infected shunts was 52%, a rate significantly larger than that in revisions of noninfected shunts (11%). Eight patients (25%) of the initially infected patients had more than one infectious episode. Predominating pathogens in patients who had shunt revisions included coagulase-negative staphylococci in 8 of 15 episodes (4 patients). Coagulase-negative staphylococci accounted for 28% and coagulase-positive staphylococci for 14% of the initial infectious episodes. Risk factors for development of shunt infection included age younger than 3 years, a previously infected shunt and surgery to revise the infected shunt. Therapy of infected shunts with antibiotics alone or with antibiotics plus an operative shunt revision resulted in similar success rates.     

Seizures in children with meningomyelocele

The charts of 111 children with meningomyelocele were reviewed. Ninety-eight had shunted hydrocephalus. Twenty-five of 111 children (24 of 98 children with shunts) had seizures. Age at onset and type of seizure varied. Brain malformation (other than Arnold-Chiari), shunt infection, and perhaps number of shunt revisions were important risk factors in seizure development. The children with seizures were more likely to be developmentally delayed.     

Prenatal evaluation and postnatal early outcomes of fetal ventriculomegaly

ObjectiveThis study aims to determine the incidence, etiology, diagnostic criteria and early outcomes of prenatally diagnosed fetal ventriculomegaly (VM).MethodsDiagnostic criteria for the fetal VM was atrial diameter of lateral ventricle measuring ≥10 mm, independent from gestational age. Results of our patients from ultrasonography (USG), karyotyping, congenital infections, and associated abnormalities were noted. Progress during pregnancy, postnatal USG results and neurobehavioral outcomes were recorded.ResultsIn our study, 40 subjects of fetal VM were recorded. 16 and 24 of those were bilateral (40%) and unilateral (60%) respectively. Female to male fetus ratio was 19/21 (0.9). Median gestational age at the diagnosis was 22 weeks (ranging between 16 and 34 weeks). While 21 VM subjects were isolated (52.5%) only 19 of the total were shown associated structural abnormalities in (47.5%) in addition to VM. Toxoplasmosis were diagnosed only in one subject (2.5%). Nineteen subjects had amniocentesis (47.5%) and 2 of them were showed abnormalities (10.5%) as follows; “inversion and duplication 8 (p11.2p23)” and “deletion 3”. VM got back in to normal size during pregnancy in 24 subjects (24/40, 60%). Eight pregnancies were terminated (8/40) (20%). Five babies passed away during neonatal and postneonatal period. Some other structural abnormalities were diagnosed after the birth at six babies who classified as mild “isolated” VM.ConclusionsOur study revealed that amongst mild VM subjects, incidence of associated abnormalities and termination rate were higher. Although most of mild VM subjects are thought to be benign, associated abnormalities should be carefully evaluated and determined pre- and postnatally.     

Shunt revisions in children--can they be avoided? Experiences from a population-based study

Background: Shunt failure is by far the most frequent problem in children with shunts, and most of them will experience this condition at some point in their lives. In order to identify causes of shunt failure, and to compare multi-component and one-piece shunt systems, we analyzed retrospectively all pediatric shunt procedures in our Department during an 11-year period. The study does not deal with shunt infections. Methods: We reviewed the records of all pediatric shunting procedures between January 1986 and December 1996. Results: The study included 161 children operated for hydrocephalus with a total of 431 procedures. The procedures included 124 (29%) primary insertions, 10 (2%) reinsertions and 297 (69%) revisions; 206 (69%) of the revisions were due to shunt failures, of which 74 (36%) were caused by the failure of the surgical technique (misplaced ventricular catheters, disconnected shunts, or misplaced peritoneal catheters). Conclusions: Improvement of the surgical technique may reduce the incidence of shunt failures and revisions. The results obtained in a small department like ours do not seem to differ substantially from those obtained in more specialized departments with a larger patient group. Practical measures that may reduce the risk of shunt failures are suggested.     

Cerebrospinal fluid shunt survival and etiology of failures: a seven-year institutional experience

BACKGROUND: Innovations in shunt technology and neuroendoscopy have been increasingly applied to shunt management. However, the relative life span of shunts and the etiology of shunt failure have not been characterized recently. METHODS: We reviewed the records of all shunting procedures at our institution between January 1992 and December 1998. Independent predictors of shunt failure were analyzed via multivariate Cox regression analysis in 836 shunting procedures. Independent predictors of the etiology of failure (infection, proximal obstruction, distal malfunction) were analyzed via multivariate logistic regression analysis in the 383 shunts which failed. RESULTS: A total of 353 pediatric patients underwent 308 shunt placements and 528 revisions. The risk (hazard ratio; HR) of shunt failure decreased as a function of time in both primary placements and revised shunts. In failed shunts, the odds of infection decreased 4-fold per year of shunt function, while the odds of distal malfunction increased 1.45-fold per year. Increasing number of shunt revisions (HR 1.31, p < 0.05), decreasing patient age in years (HR 1.04, p < 0.001), gestational age <40 weeks (HR 2.15, p < 0.001) but not the etiology of hydrocephalus were associated with an increased risk of shunt failure. Revisions versus primary placements, Dandy-Walker cysts and gestational age <40 weeks were independently associated with proximal, distal and infectious causes of failure, respectively. CONCLUSIONS: The long-term shunt revision rates observed here are similar to those reported over the past 2 decades. Shunt life span remains poorer in shunt revisions and in younger patients. Patient characteristics may suggest a specific risk and mechanism of failure, aiding in the long-term management of shunted hydrocephalus.     

Neurodevelopmental performance of very-low-birth-weight infants with mild periventricular, intraventricular hemorrhage. Outcome at 5 to 6 years of age

The neurodevelopmental outcome of 38 very-low-birth-weight neonates (birth weight, less than 1501 g) was followed up prospectively from birth to 5 to 6 years of age to assess the neurodevelopmental sequelae of mild periventricular, intraventricular hemorrhage (grades I and II). All neonates were screened for periventricular, intraventricular hemorrhage at 5 to 10 days of age. Eleven incurred a mild periventricular, intraventricular hemorrhage (group 1) and 27 had no periventricular, intraventricular hemorrhage (group 2). Each of the infants was neurodevelopmentally normal at 1 to 2 years of age. The 38 children were matched by race, age, sex, and socioeconomic status with control children (group 3) who had been born at term. On outcome measurements at 5 to 6 years of age, groups 1 and 2 scored significantly lower than group 3 on the combined test measurements and on three of the four individual measurements. Group 1 scored significantly lower than group 2 on the combined test measurements only. These data indicate that very-low-birth-weight infants are at risk for learning problems. Although children with mild periventricular, intraventricular hemorrhage did not demonstrate a significant deficit on individual test scores, the significant difference on the combined battery suggests that mild periventricular, intraventricular hemorrhage has an adverse effect on global performance.     

Disconnection as a cause of ventriculoperitoneal shunt malfunction in multicomponent shunt systems

The cause of malfunction in 275 consecutive ventriculoperitoneal (VP) shunt revisions over an 8-year period were retrospectively analyzed. In all cases the shunt revised was a multicomponent (Holter) VP shunt. Disconnections in the system accounted for 41 (15%) of the malfunctions. The more distal the connection was from the ventricle, the higher the likelihood of disconnection. Furthermore, occipitally placed shunts had a significantly higher tendency to dislocate than frontally placed shunts.     

The impact of endoscopic third ventriculostomy on the management of newly diagnosed hydrocephalus in infants

OBJECTIVES: To evaluate the role of endoscopic third ventriculostomy (ETV) as a primary treatment for hydrocephalus in children less than 1 year old and to determine its impact as a whole on the reduction of shunts necessary in a new population of hydrocephalic infants. METHODS: Data were collected prospectively on 47 infants with newly diagnosed hydrocephalus of all aetiologies who were referred between 1st April 1998 and 30th September 2000. Twenty-one patients (median age 6 weeks, range 34 weeks of gestation to 10 months) underwent ETV, while the remaining 26 patients had insertion of a ventriculoperitoneal shunt. Anatomical criteria and demonstration of third ventricle outflow obstruction on preoperative magnetic resonance imaging were used to select patients for ETV. RESULTS: There was no mortality or major morbidity following ETV. The median follow-up period was 18 (range 8-36) months. During the follow-up period, the ETV remained patent in 7 (33%) of the 21 patients. Of the 14 patients with failed ETV, 11 had insertion of a ventriculoperitoneal shunt, while 3 have undergone successful redo ETV. Therefore, in total 10 patients (48%) of the ETV group remain shunt independent. The best results were obtained in patients with congenital aqueduct stenosis with 71% (5 of 7 patients) success rate, while patients with posthaemorrhagic hydrocephalus did particularly badly with only 1 of 10 patients having a successful ETV. Overall, 10 of 47 (21%) infants with newly diagnosed hydrocephalus have avoided a shunt. CONCLUSIONS: Our results suggest that the selective use of ETV as the primary treatment in infants with hydrocephalus is safe and can lead to a reduction in the shunted population of all newly diagnosed hydrocephalic infants by up to 21%. Success of ETV is aetiology, not age dependent.     

Image-guided cerebrospinal fluid shunting in children: catheter accuracy and shunt survival

Object Cerebrospinal fluid shunt placement has a high failure rate, especially in patients with small ventricles. Frameless stereotactic electromagnetic image guidance can assist ventricular catheter placement. The authors studied the effects of image guidance on catheter accuracy and shunt survival in children. Methods Pediatric patients who underwent placement or revision of a frontal ventricular CSF shunt were retrospectively evaluated. Catheters were placed using either anatomical landmarks or image guidance. Preoperative ventricular size and postoperative catheter accuracy were quantified. Outcomes of standard and image-guided groups were compared. Results Eighty-nine patients underwent 102 shunt surgeries (58 initial, 44 revision). Image guidance was used in the placement of 56 shunts and the standard technique in 46. Shunt failure rates were not significantly different between the standard (22%) and image-guided (25%) techniques (p = 0.21, log-rank test). Ventricular size was significantly smaller in patients in the image-guided group (p < 0.02, Student t-test) and in the surgery revision group (p < 0.01). Small ventricular size did not affect shunt failure rate, even when controlling for shunt insertion technique. Despite smaller average ventricular size, the accuracy of catheter placement was significantly improved with image guidance (p < 0.01). Shunt accuracy did not affect shunt survival. Conclusions The use of image guidance improved catheter tip accuracy compared with a standard technique, despite smaller ventricular size. Failure rates were not dependent on shunt insertion technique, but an observed selection bias toward using image guidance for more at-risk catheter placements showed failure rates similar to initial surgeries.     

COMPLICATIONS IN THE TREATMENT OF HYDROCEPHALUS IN CHILDREN

ABSTRACT. Two homogenous materials of hydrocephalic children operated upon during a 20-year period (1961–1980) are compared. During the first half of the period the ventriculoatrial shunt was the only type used in 103 patients. After that there was a change to the ventriculoperitoneal shunt which was used in 104 patients, whereof 35 were converted from ventriculoatrial to ventriculoperitoneal shunts. Thus the material consists of 172 patients. The complications were less serious and the mortality rate much lower with the ventriculoperitoneal method. The revision rate, however, was about the same for both types of operation, but the revisions and the operative procedure for peritoneal shunts were generally much more simple and more rapidly performed. Therefore it is our opinion that in children the ventriculoperitoneal route is preferable to the ventriculoatrial route. With better knowledge of the underlying cause of distal obstructions in the former route we think that it will be possible to reduce the complication and revision rates even further.     

Percutaneous gastrostomy tube placement in patients with ventriculoperitoneal shunts

Objective. The purpose of this study is to determine the risk of CNS and/or peritoneal infection in children with ventriculoperitoneal shunts in whom a percutaneous gastrostomy tube is placed. Materials and methods. We placed 205 gastrostomy or gastrojejunostomy tubes from January of 1991 to December 1996. Twenty-three patients (10 boys, 13 girls) had ventriculoperitoneal shunts at the time of placement. All shunts were placed at least 1 month prior to placement of the gastrostomy tube. The patients ranged in age from 8 months to 16 years with a mean age of 6 years, 9 months. Patient weight ranged from 2 kg to 60 kg. All 23 children required long-term nutritional support due to severe neurologic impairment. No prophylactic antibiotics were given prior to the procedure. Of the patients, 21/23 had a 14-F Sacks-Vine gastrostomy tube with a fixed terminal retention device inserted, using percutaneous fluoroscopic antegrade technique. Two of the 23 patients had a Ross 14-F Flexi-flo gastrostomy tube which required a retrograde technique due to a small caliber esophagus in these children. Results. All 23 children had technically successful placements of percutaneous gastrostomy (7) or gastrojejunostomy (16) tubes. Of the children, 21/23 (91 %) had no complications from the procedure. Two of 23 (9 %) patients demonstrated signs of peritonitis after placement of their gastrostomy tubes and subsequently had shunt infections. In both, children CSF culture grew gram-positive cocci. The antegrade technique was used in both children who developed peritonitis. Conclusion. Our study indicates children with ventriculoperitoneal shunts who undergo percutaneous gastrostomy are at greater risk for infection and subsequent shunt malfunction. Therefore, we recommend prophylactic antibiotic therapy to cover for skin and oral flora. Received: 5 August 1997 Accepted: 26 December 1997     

The Modified Blalock-Taussig Shunt: A 6-Year Experience from a Developing Country

Since 1992 we have performed the modified Blalock-Taussig shunt (MBTS) for cyanotic children in Libya. This retrospective study reviews our results as a developing country, comparing them with those in the literature, and makes suggestions to improve our results. Between May 1992 and May 1998, 94 children (58 males and 36 females) underwent 100 MBTSs in Mesallata Cardiothoracic Centre, Libya. The age ranged from 4 days to 15 years, (median 12 months) and 25 patients were neonates. Patients' weights ranged from 3 to 31 kg (median 6.4 kg). Eighty-nine shunts were performed on the left side and 11 on the right. A 6-mm polytetrafluoroethylene graft was used in 68 children and a 4-mm graft in 32 cases. Tetralogy of Fallot (TOF) comprised the majority of cases (63; 67%), the remaining 31 (33%) included tricuspid atresia (13), pulmonary atresia (9), univentricular heart complex (6), and others (3). Acute shunt failure occurred in 3 cases (2 with 4-mm and 1 with 6-mm grafts), all of which had not received perioperative heparin. Hospital mortality was 6% (6 patients); risk factors were neonates, a diagnosis other than TOF, and emergency surgery. There were 12 late deaths, 6 of which were due to sepsis. Follow-up was achieved in 82 of 88 early survivors for a period of 2 to 60 months (median 26 months). All surviving patients had subjective and objective improvement. We conclude that MBTS is an excellent palliative procedure for children requiring a systemic-pulmonary shunt in developing as well as developed countries. This series shows an early mortality rate comparable to that of other studies, but the late mortality is higher, mainly due to sepsis, which warrants further attention.     

Use of acetazolamide to decrease cerebrospinal fluid production in chronically ventilated patients with ventriculopleural shunts

Acetazolamide (ACTZ), a carbonic anhydrase inhibitor, has been shown to decrease cerebrospinal fluid (CSF) production in both in vivo and in vitro animal models. We report two children with hydrocephalus who experienced multiple shunt failures, and who had externalised ventriculostomy drains (EVD) prior to ventriculopleural shunt placement. The effects of increasing doses of ACTZ on CSF production and subsequent tolerance to ventriculopleural shunts were evaluated. The patients had a 48% and a 39% decrease in their EVD CSF output when compared to baseline with maximum ACTZ dose of 75 mg/kg/day and 50 mg/kg/day, respectively (p < 0.05). This is the first report of change in CSF volume in children after extended treatment with ACTZ. ACTZ treatment in mechanically ventilated paediatric patients with hydrocephalus may improve tolerance of ventriculopleural shunts and minimise respiratory compromise. Potassium and bicarbonate supplements are required to correct metabolic disturbances.     

Pathophysiology of isolated lateral ventriculomegaly in shunted myelodysplastic children

Eight myelodysplastic children developed isolated lateral ventriculomegaly following shunt insertion for progressive hydrocephalus after closure of a myelomeningocele. In all patients a low-pressure distal slit valve (Uni-shunt) system preceded development of an isolated contralateral ventricle. Six of 8 children required a second contralateral shunt for a symptomatic isolated ventricle. Magnetic resonance imaging demonstrated a collapsed ventricle ipsilateral to the shunt secondary to distortion of the foramen of Monro. This was clearly depicted using three-dimensional color reconstructions of the ventricular anatomy. Low-pressure distal slit valves should be avoided in myelodysplastic children to prevent postshunt ventricle isolation.     

Use of acetazolamide to decrease cerebrospinal fluid production in chronically ventilated patients with ventriculopleural shunts.

Acetazolamide (ACTZ), a carbonic anhydrase inhibitor, has been shown to decrease cerebrospinal fluid (CSF) production in both in vivo and in vitro animal models. We report two children with hydrocephalus who experienced multiple shunt failures, and who had externalised ventriculostomy drains (EVD) prior to ventriculopleural shunt placement. The effects of increasing doses of ACTZ on CSF production and subsequent tolerance to ventriculopleural shunts were evaluated. The patients had a 48% and a 39% decrease in their EVD CSF output when compared to baseline with maximum ACTZ dose of 75 mg/kg/day and 50 mg/kg/day, respectively (p < 0.05). This is the first report of change in CSF volume in children after extended treatment with ACTZ. ACTZ treatment in mechanically ventilated paediatric patients with hydrocephalus may improve tolerance of ventriculopleural shunts and minimise respiratory compromise. Potassium and bicarbonate supplements are required to correct metabolic disturbances.     

Primary ventriculo-peritoneal shunts in treatment of hydrocephalus associated with myelomeningocele

In 50 children suffering from open myelomeningocele, a ventriculo-peritoneal shunt was employed as the primary procedure for control of hydrocephalus. In 11 cases the system was ultimately replaced by a ventriculo-atrial shunt, though this may not always have been necessary. In the remaining 39 patients satisfactory control of hydrocephalus was achieved. Obstruction, particularly of the peritoneal catheter, occurred frequently in the first 6 months but no revisions were required after 2 years. It is concluded that while ventriculo-peritoneal and ventriculo-atrial shunts achieve comparable success in controlling hydrocephalus, the former, due to the relatively innocuous complications, offers significant long-term advantages.     

Comparison of total versus partial revision of initial ventriculoperitoneal shunt failures

BACKGROUND: Optimal surgical management of patients presenting with shunt failure in the age of neuroendoscopy remains complex. The value of replacing the entire shunt system as opposed to a single shunt component has not been assessed. METHODS: We reviewed the records of all pediatric patients who underwent their first shunt revision between January 1992 and December 1998. Patients with primary shunt failure attributed solely to proximal catheter obstruction or distal catheter obstruction were included for analysis. Shunt revisions were classified as total (entire shunt replaced) or partial (only malfunctioning component replaced). Kaplan-Meier (shunt survival curves) and log rank analysis were used to compare failure rates between partially and totally revised shunts according to the underlying diagnosis and failed shunt part. Significant differences in univariate analysis were confirmed with a multivariate proportional hazards regression model. RESULTS: 301 pediatric patients underwent primary shunt revision (183 total, 118 partial revisions). All shunts utilized distal slit peritoneal catheters. In shunt failures attributed to proximal obstruction, reutilization of the distal catheter was associated with a 57% increased risk of subsequent shunt failure (hazard ratio 1.57, 95% confidence interval 1.19-3.49). In shunt failures attributed to distal obstruction, subsequent shunt survival was not affected by reutilization of the proximal catheter (p = 0.581). When stratified according to the etiology of hydrocephalus, only patients with intraventricular hemorrhage (IVH) failed to demonstrate greater survival of totally revised shunts. CONCLUSIONS: In this series, in the setting of proximal shunt catheter obstruction, reutilizing the functional distal catheter was associated with an increase in subsequent shunt failure rates compared to revising the entire shunt system. Total revision was not associated with improved shunt survival in patients with IVH.     

Life expectancy of ventriculosubgaleal shunt revisions

The subgaleal shunt has been and is currently used for the temporary bypass of the normal cerebrospinal fluid (CSF) pathways. We retrospectively reviewed all subgaleal shunts placed at the Children's Hospital, Birmingham, Ala., USA, from 1993 to the present and examined the life expectancy of revisions of this temporary method of CSF diversion. The average length of survival of primary, secondary and tertiary subgaleal shunts in this population was 37.4, 32.4 and 19.6 days, respectively. This current review demonstrates that the majority of patients in whom a subgaleal shunt is utilized may continue to obtain therapeutic diversion of their CSF for greater than 2.5 months with intermittent subgaleal shunt revisions. In the majority of cases, this length of time is sufficient to manage and resolve issues that would make ventriculoperitoneal shunting undesirable.     

Ductus arteriosus blood flow during first 48 hours of life.

A volumetric Doppler technique was used to measure net ductus arteriosus shunt during the first 48 hours of life in 30 infants of less than 33 weeks'' gestation, and in 10 full term infants. In the full term infants a left to right shunt of 62 ml/kg/minute (95% confidence limits 43-82) shortly after birth decreased rapidly over the first 12 hours and was not measurable by 48 hours. The preterm infants had smaller left to right shunts shortly after birth--49 ml/kg/minute (95% confidence limits 38-59). There was no obvious subsequent change in the mean shunt, although by 48 hours there was greater variation in the size of the shunt. The respiratory distress syndrome did not affect the size of the ductal shunt, but the shorter the gestation period the larger the shunt by 48 hours. A ductal flow of greater than 70 ml/kg/minute at 48 hours of age predicted the subsequent development of a ductal murmur with 75% sensitivity and 100% specificity.