Considerações hidrodinâmicas sobre a derivação liquórica V: alterações nos dimensionamentos originais do sistema valvular no momento do implante alteram suas características hidrodinâmicas e induzem a erros de avaliação clínica pelo neurocirurgião

Suriano, Ítalo Capraro; Maset, Angelo L.; Fontolan, Thamires Arruda; Monteiro, Ruy; Pinto, José Roberto Aparecido dos Santos; Andrade, José; Freitas, Diogo Gonçalves; Rodrigues, Thiago; Paz, Daniel Araújo; Cavalheiro, Sérgio

doi:10.1055/s-0038-1625710

Cited by 2 publications

(6 citation statements)

References 11 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In a previous work,[17] we have demonstrated that small changes either in diameter or length of original peritoneal catheters compromise the resistive effect of the shunt assembly. Shunt selection was at random, and we tested adult-type, high- and medium-pressure shunts.…”

Section: Introductionmentioning

confidence: 99%

“…Neurosurgeons routinely cut off pieces of the peritoneal catheter upon shunt implantation/revision, and this occurs more frequently in the pediatric and newborn population due obviously to the height of the patients. In a previous work,[ 17 ] we have demonstrated that small changes either in diameter or length of original peritoneal catheters compromise the resistive effect of the shunt assembly. Shunt selection was at random, and we tested adult-type, high- and medium-pressure shunts.…”

Section: Introductionmentioning

confidence: 99%

“…Shunt selection was at random, and we tested adult-type, high- and medium-pressure shunts. [ 17 ] Cutting off pieces of the peritoneal catheter lowered shunt resistance and shunts operated in a lower pressure range. Also, changes in internal diameter (i.d.)…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Shunt implantations and peritoneal catheters: Do not cut beyond 20 cm

Monteiro

et al. 2014

Surg Neurol Int

Self Cite

View full text Add to dashboard Cite

Background:Ventriculoperitoneal shunts are supplied with long peritoneal catheters, most commonly between 80 and 120 cm long. ISO/DIS 7197/2006[15] shunt manufacturing procedures include peritoneal catheter as an integrate of the total resistance. Cutting pieces of peritoneal catheters upon shunt implantation or revision is a common procedure.Methods:We evaluated five shunts assembled with different total pressure resistances and variable peritoneal catheter lengths in order to clarify the changes that occurred in the hydrodynamic profile when peritoneal catheters were cut upon shunt implantation or shunt revision.Results:Originally, all shunts performed within the operational range. Shunt 1 performed in a lower pressure range at 200 mm cut off peritoneal catheter and as a low-pressure shunt with –300 mm cut off. Shunt 2 was manufactured to run at the higher border pressure range, and it went out of specification with a 300 mm cut off. Shunt 3 was manufactured to run close to the lower border pressure range, and at 100 mm cutoff, it was already borderline in a lower resistive category. Other shunts also responded similarly.Conclusion:The limit to maintain a shunt in its original pressure settings was 20 cm peritoneal catheter cutting length. By cutting longer pieces of peritoneal catheter, one would submit patients to a less-resistive regimen than intended and his reasoning will be compromised. The pediatric population is more prone to suffer from the consequences of cutting catheters. Shunt manufacturers should consider adopting peritoneal catheters according to the age (height) of the patient.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Shunt implantations and peritoneal catheters: Do not cut beyond 20 cm

Monteiro

et al. 2014

Surg Neurol Int

Self Cite

View full text Add to dashboard Cite

show abstract

“…Changes in the shunt components can modify the neurological valve pressure class and interfere in the treatment of hydrocephalus. Allin et al (2008), Czosnyka et al (1997Czosnyka et al ( , 2002 and Suriano et al (2012) presented their results with statistical analyses. However, there was no evidence of evaluation of the testing rigs used in the tests or the analysis of experimental uncertainties.…”

Section: Introductionmentioning

confidence: 99%

“…Suriano et al (2012), determined the relative pressure-flow rate of a shunt on a testing rig to show that changes to the original diameter and length of the peritoneal catheter, during installation of the implant or surgical revision, change the hydrodynamic behavior of the drainage system and can induce errors in the clinical evaluation of the patient by the neurosurgeon. Changes in the shunt components can modify the neurological valve pressure class and interfere in the treatment of hydrocephalus.…”

Section: Introductionmentioning

confidence: 99%

Evaluation of flow rate accuracy and pressure measurements of testing rig for neurological valve hydrodynamic tests

Pinto¹,

Maset²,

Andrade³

et al. 2014

RBEB

Self Cite

View full text Add to dashboard Cite

Introduction: Increased production and disorders in the circulation or absorption of cerebrospinal fluid (CSF) leads to increased intracranial pressure and causes a condition called hydrocephalus. The most common treatment for this disorder is the implantation of a ventricle-peritoneal shunt, which consists of the insertion of a ventricular catheter in the cerebral ventricle, a neurological valve for drainage control and a peritoneal catheter that leads the CSF to the abdominal region. The International Organization for Standardization (ISO) 7197 introduced requirements for the design and production of the shunts and neurological valve, including in vitro hydrodynamic tests, which are indispensable for evaluating the performance of the CSF drainage systems. Methods: A testing rig built in accordance with ISO 7197 was evaluated for the uncertainty of flow and opening and closing pressure measurements, the pressure-flow relationship and reflux neurological valve resistance. The infusion pump and pressure measurement system were evaluated for calibration, hysteresis behavior and stability to determine the experimental uncertainties from hydrodynamic testing of two commercial products. Results: The equipment showed uncertainties of less than 1% in the infusion pump, less than 4% in the pressure sensor and adequate performance for the hydrodynamic tests. Conclusion: The hydrodynamic test rig allowed the opening and closing pressures and the resistance to reflux to be obtained, and it also allowed the determination of the pressure and flow rate characteristics of two neurological commercial valves with experimental uncertainties that do not impact the results and the evaluation of in vitro performance of a shunt.

show abstract

Considerações hidrodinâmicas sobre a derivação liquórica V: alterações nos dimensionamentos originais do sistema valvular no momento do implante alteram suas características hidrodinâmicas e induzem a erros de avaliação clínica pelo neurocirurgião

Cited by 2 publications

References 11 publications

Shunt implantations and peritoneal catheters: Do not cut beyond 20 cm

Shunt implantations and peritoneal catheters: Do not cut beyond 20 cm

Evaluation of flow rate accuracy and pressure measurements of testing rig for neurological valve hydrodynamic tests

Contact Info

Product

Resources

About