Tympanic membrane displacement testing in regular assessment of intracranial pressure in eight children with shunted hydrocephalus

Object. The authors assessed the accuracy and repeatability of the tympanic membrane displacement (TMD) test, an audiometric technique that is used to evaluate changes in intracranial pressure (ICP) in children with shunted hydrocephalus. Methods. A prospective comparative evaluation of 31 clinical episodes of shunt malfunction was made by using the serial TMD test and direct ICP measurement in eight children with shunted hydrocephalus between January 1995 and February 1996. The volume displacement of the tympanic membrane (Vm) on stapedial contraction was inward for raised ICP in 11 instances and ranged from −120 to −539 nl (mean −263.5 nl). This was confirmed by direct ICP monitoring, which showed values ranging from 20 to 30 mm Hg (mean 26 mm Hg). The TMD test measurement (Vm) in 18 instances of low ICP ranged from 263 to 717 nl (mean 431.3 nl); this was corroborated by direct ICP measurement, which ranged from 3 to 7 mm Hg (mean 4.2 mm Hg). The normal baseline Vm values obtained when patients were asymptomatic ranged from −98 to 197 nl (mean 110 nl). As a noninvasive diagnostic tool used in predicting changes in ICP, the TMD test had a sensitivity of 83% and specificity of 100%. The positive predictive value of the test was 100% and the negative predictive value was 29%. Conclusions. The TMD test can be used on a regular basis as a reproducible investigative tool in the assessment of ICP in children with shunted hydrocephalus, thereby reducing the need for invasive ICP monitoring. The equipment necessary to perform this testing is mobile. It will provide a useful serial guide to ICP abnormalities in children with shunted hydrocephalus.

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A method of estimating intracranial decompensation in man

Journal of Neurosurgery ◽

10.3171/jns.1976.45.2.0155 ◽

1976 ◽

Vol 45 (2) ◽

pp. 155-158 ◽

Cited By ~ 15

Author(s):

Jerzy Szewczykowski ◽

Pawel Dytko ◽

Adam Kunicki ◽

Jolanta Korsak-Sliwka ◽

Stanislaw Sliwka ◽

...

Keyword(s):

Standard Deviation ◽

Intracranial Pressure ◽

Characteristic Feature ◽

Computer System ◽

Monitoring System ◽

New Method ◽

Icp Monitoring ◽

Content Type ◽

On Line ◽

Fine Print

✓ A new method of estimating intracranial decompensation in man is described. An on-line computer system is connected to an intracranial pressure (ICP) monitoring system to compute regression plots of mean ICP vs standard deviation; standard deviation is used as a measure of ICP instability. Two zones with distinctly different slopes are a characteristic feature of these plots. It is thought that the changes of slope signify intracranial decompensation.

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Intracranial pressure monitoring after elective intracranial surgery

Journal of Neurosurgery ◽

10.3171/jns.1988.69.4.0540 ◽

1988 ◽

Vol 69 (4) ◽

pp. 540-544 ◽

Cited By ~ 47

Author(s):

Shlomi Constantini ◽

Shamay Cotev ◽

Z. Harry Rappaport ◽

Shlomo Pomeranz ◽

Mordechai N. Shalit

Keyword(s):

Risk Factors ◽

Intracranial Pressure ◽

Postoperative Management ◽

Clinical Deterioration ◽

Icp Monitoring ◽

Repeat Surgery ◽

Content Type ◽

Intracranial Surgery ◽

Tumor Bed ◽

Fine Print

✓ A retrospective study of 514 consecutive patients whose intracranial pressure (ICP) was monitored after elective supratentorial or infratentorial surgery is reported. Of the 412 patients operated on in the supratentorial region, 76 (18.4%) had a postoperative sustained ICP elevation exceeding 20 torr. Abnormally high ICP occurred after 13 (12.7%) of the 102 infratentorial operations. Risk factors for postoperative ICP elevation were: resection of glioblastoma in 27.2% of cases, repeat surgery in 42.9% of cases, and protracted surgery (> 6 hours) in 41.7% of cases. Of the 89 patients with elevated ICP, 47 (52.8%) had an associated clinical deterioration. In 19 of these, the rise in ICP occurred before this deterioration was noticed, leading as a rule to quick diagnostic and management response. In eight patients clinical deterioration was noticed before the rise in ICP, and in 20 it happened simultaneously. The higher the level of ICP elevation, the greater were the chances of associated deterioration. The most common findings on computerized tomography scanning in 35 of the 89 patients with elevated ICP were brain edema (19 cases) and bleeding in the tumor bed (15 cases). Mannitol, thiopental, additional hyperventilation, and reintubation (in patients who were previously extubated) were used to reduce ICP, in addition to surgical decompression whenever indicated. Thirteen patients with raised ICP and clinical deterioration underwent reoperation. The postoperative infection rate was 1.2% (six cases). In only one patient could infection be attributed to ICP monitoring. It was concluded that ICP monitoring is advantageous in the immediate postoperative management after elective intracranial surgery and is almost risk-free. It should therefore be used liberally, especially when risk factors for ICP elevation can be identified prior to the end of surgery.

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Relationship between intracranial pressure and other clinical variables in patients with aneurysmal subarachnoid hemorrhage

Journal of Neurosurgery ◽

10.3171/jns.2004.101.3.0408 ◽

2004 ◽

Vol 101 (3) ◽

pp. 408-416 ◽

Cited By ~ 144

Author(s):

Gregory G. Heuer ◽

Michelle J. Smith ◽

J. Paul Elliott ◽

H. Richard Winn ◽

Peter D. Leroux

Keyword(s):

Subarachnoid Hemorrhage ◽

Intracranial Pressure ◽

Aneurysmal Subarachnoid Hemorrhage ◽

Clinical Grade ◽

Icp Monitoring ◽

Content Type ◽

Poor Grade ◽

Symptomatic Vasospasm ◽

Increased Icp ◽

Fine Print

Object. Increased intracranial pressure (ICP) is well known to affect adversely patients with head injury. In contrast, the variables associated with ICP following aneurysmal subarachnoid hemorrhage (SAH) and their impact on outcome have been less intensely studied. Methods. In this retrospective study the authors reviewed a prospective observational database cataloging the treatment details in 433 patients with SAH who had undergone surgical occlusion of an aneurysm as well as ICP monitoring. All 433 patients underwent postoperative ICP monitoring, whereas only 146 (33.7%) underwent both pre- and postoperative ICP monitoring. The mean maximal ICP was 24.9 ± 17.3 mm Hg (mean ± standard deviation). During their hospital stay, 234 patients (54%) had elevated ICP (> 20 mm Hg), including 136 of those (48.7%) with a good clinical grade (Hunt and Hess Grades I–III) and 98 (63.6%) of the 154 patients with a poor grade (Hunt and Hess Grades IV and V) on admission. An increased mean maximal ICP was associated with several admission variables: worse Hunt and Hess clinical grade (p < 0.0001), a lower Glasgow Coma Scale (GSC) motor score (p < 0.0001); worse SAH grade based on results of computerized tomography studies (p < 0.0001); intracerebral hemorrhage (p = 0.024); severity of intraventricular hemorrhage (p < 0.0001); and rebleeding (p = 0.0048). Both intraoperative cerebral swelling (p = 0.0017) and postoperative GCS score (p < 0.0001) were significantly associated with a raised ICP. Variables such as patient age, aneurysm size, symptomatic vasospasm, intraoperative aneurysm rupture, and secondary cerebral insults such as hypoxia were not associated with raised ICP. Increased ICP adversely affected outcome: 71.9% of patients with normal ICP demonstrated favorable 6-month outcomes postoperatively, whereas 63.5% of patients with ICP between 20 and 50 mm Hg and 33.3% with ICP greater than 50 mm Hg demonstrated favorable outcomes. Among 21 patients whose raised ICP did not respond to mannitol therapy, all experienced a poor outcome and 95.2% died. Among 145 patients whose elevated ICP responded to mannitol, 66.9% had a favorable outcome and only 20.7% were dead 6 months after surgery (p < 0.0001). According to results of multivariate analysis, however, ICP was not an independent outcome predictor (odds ratio 1.26, 95% confidence interval 0.28–5.68). Conclusions. Increased ICP is common after SAH, even in patients with a good clinical grade. Elevated ICP post-SAH is associated with a worse patient outcome, particularly if ICP does not respond to treatment. This association, however, may depend more on the overall severity of the SAH than on ICP alone.

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Experience with Althesin in the management of persistently raised ICP following severe head injury

Journal of Neurosurgery ◽

10.3171/jns.1986.64.3.0414 ◽

1986 ◽

Vol 64 (3) ◽

pp. 414-419 ◽

Cited By ~ 4

Author(s):

Ross Bullock ◽

James R. van Dellen ◽

Derek Campbell ◽

Ian Osborn ◽

S. Gustav Reinach

Keyword(s):

Patient Outcome ◽

Head Injury ◽

Intracranial Pressure ◽

Cerebral Perfusion ◽

Severe Head Injury ◽

Perfusion Pressure ◽

Surgical Decompression ◽

Icp Monitoring ◽

Content Type ◽

Fine Print

✓ Of 243 patients who underwent intracranial pressure (ICP) monitoring after severe head injury, 42 (17%) were found to have severe persistently raised ICP, in spite of hyperventilation, mannitol, and surgical decompression. Althesin was infused to reduce ICP in these patients. This agent was shown to be effective and safe in reducing ICP, and a significant improvement in cerebral perfusion pressure was demonstrated. In this respect, Althesin may be more effective than barbiturates. However, no improvement in patient outcome was demonstrated in this series.

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Pressure-volume conditions in patients with subarachnoid and/or intraventricular hemorrhage

Journal of Neurosurgery ◽

10.3171/jns.1985.63.3.0398 ◽

1985 ◽

Vol 63 (3) ◽

pp. 398-403 ◽

Cited By ~ 22

Author(s):

Michael Kosteljanetz

Keyword(s):

Intracranial Pressure ◽

Blood Volume ◽

Intraventricular Hemorrhage ◽

Bolus Injection ◽

Pulse Amplitude ◽

Volume Index ◽

Icp Monitoring ◽

Content Type ◽

The Relationship ◽

Fine Print

✓ Pressure-volume conditions were studied in 17 patients with subarachnoid and/or intraventricular hemorrhage, who underwent continuous intracranial pressure (ICP) monitoring. The pressure-volume index (PVI) technique was used. The interrelationship between the ICP pulse amplitude and compliance was also examined. All patients were admitted in Hunt and Hess Grades II to V, and 11 had a proven aneurysm. The ICP was above 15 mm Hg in all patients during some part of the monitoring period. The pressure-volume conditions were abnormal in all patients. Median PVI was 12.7 ml (5.8 to 40.0 ml). The PVI did not correlate with ICP; the PVI based on bolus injection was significantly greater than PVI based on fluid withdrawal. The ICP pulse amplitude varied from 1.5 to 15 mm Hg and rose concomitantly with increasing ICP. Considering the pulsatile shift in intracranial blood volume as an endogenous bolus that increases ICP from the diastolic (Pdiast) to the systolic (Psyst) level, an equation was derived from the PVI model that describes the relationship between the Psyst:Pdiast ratio and the PVI.

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Enigma of raised intracranial pressure in patients with complex craniosynostosis: the role of abnormal intracranial venous drainage

Journal of Neurosurgery ◽

10.3171/jns.2001.94.3.0377 ◽

2001 ◽

Vol 94 (3) ◽

pp. 377-385 ◽

Cited By ~ 117

Author(s):

Wendy J. Taylor ◽

Richard D. Hayward ◽

Pierre Lasjaunias ◽

Jonathan A. Britto ◽

Dominic N. P. Thompson ◽

...

Keyword(s):

Intracranial Pressure ◽

Venous Drainage ◽

Venous Hypertension ◽

Apert Syndrome ◽

Raised Intracranial Pressure ◽

Icp Monitoring ◽

Venous Anatomy ◽

Content Type ◽

Complex Forms ◽

Fine Print

Object. In this study the authors investigated whether patterns of intracranial venous drainage in children with complex craniosynostosis associated with raised intracranial pressure (ICP) were abnormal and, thus, could support the theory that venous hypertension is a major contributor to raised ICP that can lead to impaired visual function or even blindness in these patients. Methods. The authors analyzed the anatomy of intracranial venous drainage as demonstrated in the results of 24 angiography studies obtained in 23 patients, all of whom had either a craniosynostosis-related syndrome (18 patients) or a nonsyndromic multisutural synostosis (five patients). Twenty-one patients had experienced raised ICP (in 19 patients diagnosis was based on invasive ICP monitoring and in two patients on clinical grounds alone) 1 to 6 weeks before undergoing angiography. Of the two remaining patients (both with Apert syndrome) whose ICP monitoring was normal immediately before angiography, each had undergone two previous cranial vault expansion procedures. On results of 18 angiography studies a 51 to 99% stenosis or no flow at all could be observed in the sigmoid—jugular sinus complex either bilaterally (11 patients) or unilaterally (seven patients). In 11 of these patients a florid collateral circulation through the stylomastoid emissary venous plexus was also seen. Two angiography studies were performed in one patient with Crouzon syndrome. A comparison of the two studies demonstrated a progression of the abnormal venous anatomy in that case. The authors found no obvious correlation between each patient's baseline ICP and the degree of abnormality of their venous anatomy, as judged on the basis of a venous-phase angiography severity score. Conclusions. Based on their findings, the authors assert that in children with complex forms of craniosynostosis in whom other factors, such as hydrocephalus, are absent, abnormalities of venous drainage that particularly affect the sigmoid—jugular sinus complex produce a state of venous hypertension that, in turn, is responsible for the majority of cases of raised ICP. The incidence of these changes is unknown, but an analysis of the ages of the children in this study indicated that the period of particular vulnerability to the effects of venous hypertension lasts until the affected child is approximately 6 years old. After that age the collateral venous drainage through the stylomastoid plexus will likely become sufficient to allow ICP to normalize.

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Evaluation of the Carba NP Test for Rapid Detection of Carbapenemase-Producing Enterobacteriaceae and Pseudomonas aeruginosa

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.00878-13 ◽

2013 ◽

Vol 57 (9) ◽

pp. 4578-4580 ◽

Cited By ~ 147

Author(s):

Nathalie Tijet ◽

David Boyd ◽

Samir N. Patel ◽

Michael R. Mulvey ◽

Roberto G. Melano

Keyword(s):

Pseudomonas Aeruginosa ◽

Positive Predictive Value ◽

Negative Predictive Value ◽

Predictive Value ◽

Rapid Detection ◽

False Negative ◽

Bacterial Extract ◽

Content Type ◽

Negative Results ◽

False Negative Results

ABSTRACTThe Carba NP test was evaluated against a panel of 244 carbapenemase- and non-carbapenemase-producingEnterobacteriaceaeandPseudomonas aeruginosaisolates. We confirmed the 100% specificity and positive predictive value of the test, but the sensitivity and negative predictive value were 72.5% and 69.2%, respectively, and increased to 80% and 77.3%, respectively, using a more concentrated bacterial extract. False-negative results were associated with mucoid strains or linked to enzymes with low carbapenemase activity, particularly OXA-48-like, which has emerged globally in enterobacteria.

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Flushing in relation to a possible rise in intracranial pressure: documentation of an unusual clinical sign

Journal of Neurosurgery ◽

10.3171/jns.2000.92.6.1040 ◽

2000 ◽

Vol 92 (6) ◽

pp. 1040-1044 ◽

Cited By ~ 4

Author(s):

Gregory W. Hornig

Keyword(s):

Traumatic Brain Injury ◽

Brain Injury ◽

Intracranial Pressure ◽

Intraventricular Hemorrhage ◽

Pneumococcal Meningitis ◽

Clinical Importance ◽

Neurological Deterioration ◽

Content Type ◽

Transient Nature ◽

Fine Print

✓ This report documents clinical features in five children who developed transient reddening of the skin (epidermal flushing) in association with acute elevations in intracranial pressure (ICP). Four boys and one girl (ages 9–15 years) deteriorated acutely secondary to intracranial hypertension ranging from 30 to 80 mm Hg in the four documented cases. Two patients suffered from ventriculoperitoneal shunt malfunctions, one had diffuse cerebral edema secondary to traumatic brain injury, one was found to have pneumococcal meningitis and hydrocephalus, and one suffered an intraventricular hemorrhage and hydrocephalus intraoperatively. All patients were noted to have developed epidermal flushing involving either the upper chest, face, or arms during their period of neurological deterioration. The response was transient, typically lasting 5 to 15 minutes, and dissipated quickly. The flushing reaction is postulated to be a centrally mediated response to sudden elevations in ICP. Several potential mechanisms are discussed. Flushing has clinical importance because it may indicate significant elevations in ICP when it is associated with neurological deterioration. Because of its transient nature, the importance of epidermal flushing is often unrecognized; its presence confirms the need for urgent treatment.

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Effect of stimulation of the medullary reticular formation on cerebral vasomotor tonus and intracranial pressure

Journal of Neurosurgery ◽

10.3171/jns.1987.66.4.0548 ◽

1987 ◽

Vol 66 (4) ◽

pp. 548-554 ◽

Cited By ~ 8

Author(s):

Seigo Nagao ◽

Tsukasa Nishiura ◽

Hideyuki Kuyama ◽

Masakazu Suga ◽

Takenobu Murota

Keyword(s):

Intracranial Pressure ◽

Reticular Formation ◽

Cerebral Blood Volume ◽

Systemic Arterial Pressure ◽

Brain Swelling ◽

Dorsomedial Nucleus ◽

Medullary Reticular Formation ◽

Content Type ◽

Fine Print ◽

Stimulation Of

✓ The authors report the results of a study to evaluate the effect of stimulation of the medullary reticular formation on cerebral vasomotor tonus and intracranial pressure (ICP) after the hypothalamic dorsomedial nucleus and midbrain reticular formation were destroyed. Systemic arterial pressure (BP), ICP, and local cerebral blood volume (CBV) were continuously recorded in 32 cats. To assess the changes in the cerebral vasomotor tonus, the vasomotor index defined by the increase in ICP per unit change in BP was calculated. In 29 of the 32 animals, BP, ICP, and CBV increased simultaneously immediately after stimulation. The increase in ICP was not secondary to the increase in BP, because the vasomotor index during stimulation was significantly higher than the vasomotor index after administration of angiotensin II. The vasomotor index was high during stimulation of the area around the nucleus reticularis parvocellularis. In animals with the spinal cord transected at the C-2 vertebral level, ICP increased without a change in BP. These findings indicate that the areas stimulated in the medullary reticular formation play an important role in decreasing cerebral vasomotor tonus. This effect was not influenced by bilateral superior cervical ganglionectomy, indicating that there is an intrinsic neural pathway that regulates cerebral vasomotor tonus directly. In three animals, marked biphasic or progressive increases in ICP up to 100 mm Hg were evoked by stimulation. The reduction of cerebral vasomotor tonus and concomitant vasopressor response induced by stimulation of the medullary reticular formation may be one of the causes of acute brain swelling.

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