Risk factors and complications of intracranial pressure monitoring with a fiberoptic device

Consensus summary statement of the International Multidisciplinary Consensus Conference on Multimodality Monitoring in Neurocritical Care: a statement for healthcare professionals from the Neurocritical Care Society and the European Society of Intensive Care Medicine

Neurocritical care depends, in part, on careful patient monitoring but as yet there are little data on what processes are the most important to monitor, how these should be monitored, and whether monitoring these processes is cost-effective and impacts outcome. At the same time, bioinformatics is a rapidly emerging field in critical care but as yet there is little agreement or standardization on what information is important and how it should be displayed and analyzed. The Neurocritical Care Society in collaboration with the European Society of Intensive Care Medicine, the Society for Critical Care Medicine, and the Latin America Brain Injury Consortium organized an international, multidisciplinary consensus conference to begin to address these needs. International experts from neurosurgery, neurocritical care, neurology, critical care, neuroanesthesiology, nursing, pharmacy, and informatics were recruited on the basis of their research, publication record, and expertise. They undertook a systematic literature review to develop recommendations about specific topics on physiologic processes important to the care of patients with disorders that require neurocritical care. This review does not make recommendations about treatment, imaging, and intraoperative monitoring. A multidisciplinary jury, selected for their expertise in clinical investigation and development of practice guidelines, guided this process. The GRADE system was used to develop recommendations based on literature review, discussion, integrating the literature with the participants' collective experience, and critical review by an impartial jury. Emphasis was placed on the principle that recommendations should be based on both data quality and on trade-offs and translation into clinical practice. Strong consideration was given to providing pragmatic guidance and recommendations for bedside neuromonitoring, even in the absence of high quality data.

Consensus summary statement of the International Multidisciplinary Consensus Conference on Multimodality Monitoring in Neurocritical Care : a statement for healthcare professionals from the Neurocritical Care Society and the European Society of Intensive Care Medicine

Neurocritical care depends, in part, on careful patient monitoring but as yet there are little data on what processes are the most important to monitor, how these should be monitored, and whether monitoring these processes is cost-effective and impacts outcome. At the same time, bioinformatics is a rapidly emerging field in critical care but as yet there is little agreement or standardization on what information is important and how it should be displayed and analyzed. The Neurocritical Care Society in collaboration with the European Society of Intensive Care Medicine, the Society for Critical Care Medicine, and the Latin America Brain Injury Consortium organized an international, multidisciplinary consensus conference to begin to address these needs. International experts from neurosurgery, neurocritical care, neurology, critical care, neuroanesthesiology, nursing, pharmacy, and informatics were recruited on the basis of their research, publication record, and expertise. They undertook a systematic literature review to develop recommendations about specific topics on physiologic processes important to the care of patients with disorders that require neurocritical care. This review does not make recommendations about treatment, imaging, and intraoperative monitoring. A multidisciplinary jury, selected for their expertise in clinical investigation and development of practice guidelines, guided this process. The GRADE system was used to develop recommendations based on literature review, discussion, integrating the literature with the participants' collective experience, and critical review by an impartial jury. Emphasis was placed on the principle that recommendations should be based on both data quality and on trade-offs and translation into clinical practice. Strong consideration was given to providing pragmatic guidance and recommendations for bedside neuromonitoring, even in the absence of high quality data.

The evolution of neurocritical care

Although neurocritical care as a subspecialty is a relatively young field of medicine, its origins can be traced back to ancient times. This article focuses on the progression of neurocritical care from prehistoric trepanation procedures, through the development of mechanical ventilation, management of increased intracranial pressure, and traumatic brain injury, to the establishment of the first "real" intensive care units, and finally to modern monitoring in neurocritical care, management of post-cardiac arrest patients, and the diagnosis of brain death. This article also focuses on the future direction of neurocritical care.

Clinical and radiological findings in long-term intracranial pressure monitoring

BACKGROUND

Advantages of telemetric devices for long-term intracranial pressure (ICP) measurement have been mentioned several times in the literature. However, descriptions of associated complications are lacking. Therefore, the presented observational study focused on clinical and radiological findings after insertion of an intraparenchymal telemetric ICP monitor.

METHODS

Between April 2010 and February 2013, 185 telemetric ICP catheters were implanted for diagnostic purposes. All patients were clinically followed. Radiological, microbiological and clinical data were analysed.

RESULTS

One brain abscess (0.5 %) and two cutaneous infections (1.1 %) occurred in 185 patients. Staphylococcus spp. could be detected in all cases. Six patients (3.2 %) suffered from single new-onset seizures and one patient (0.5 %) from a temporary hemiparesis. Intracerebral haemorrhages occurred in 15.6 %, most of the time as small punctate bleedings. Perifocal oedematous reactions surrounding inserted telemetric catheters could be observed in 46.9 %. Multiple imaging studies revealed a tendency of complete oedema resolution over time.

CONCLUSIONS

Infectious as well as haemorrhagic complication rates are well comparable with the common literature. The long-term implantation of an ICP probe does not seem to increase the risk of wound infections or brain abscess formation. Surprisingly, very high numbers of oedematous reactions after insertion of the intraparenchymal ICP monitor were seen. Reasons therefore could only be speculated upon.

The complications and the position of the Codman MicroSensor™ ICP device: an analysis of 549 patients and 650 Sensors

BACKGROUND

Complications of and insertion depth of the Codman MicroSensor ICP monitoring device (CMS) is not well studied.

OBJECTIVE

To study complications and the insertion depth of the CMS in a clinical setting.

METHODS

We identified all patients who had their intracranial pressure (ICP) monitored using a CMS device between 2002 and 2010. The medical records and post implantation computed tomography (CT) scans were analyzed for occurrence of infection, hemorrhage and insertion depth.

RESULTS

In all, 549 patients were monitored using 650 CMS. Mean monitoring time was 7.0 ± 4.9 days. The mean implantation depth was 21.3 ± 11.1 mm (0-88 mm). In 27 of the patients, a haematoma was identified; 26 of these were less than 1 ml, and one was 8 ml. No clinically significant bleeding was found. There was no statistically significant increase in the number of hemorrhages in presumed coagulopathic patients. The infection rate was 0.6 % and the calculated infection rate per 1,000 catheter days was 0.8.

CONCLUSION

The risk for hemorrhagic and infectious complications when using the CMS for ICP monitoring is low. The depth of insertion varies considerably and should be taken into account if patients are treated with head elevation, since the pressure is measured at the tip of the sensor. To meet the need for ICP monitoring, an intraparenchymal ICP monitoring device should be preferred to the use of an external ventricular drainage (EVD).

Decreased risk of acute kidney injury with intracranial pressure monitoring in patients with moderate or severe brain injury

OBJECT

The authors undertook this study to evaluate the effects of continuous intracranial pressure (ICP) monitoring-directed mannitol treatment on kidney function in patients with moderate or severe traumatic brain injury (TBI).

METHODS

One hundred sixty-eight patients with TBI were prospectively assigned to an ICP monitoring group or a conventional treatment control group based on the Brain Trauma Foundation guidelines. Clinical data included the dynamic changes of patients' blood concentrations of cystatin C, creatinine (Cr), and blood urea nitrogen (BUN); mannitol use; and 6-month Glasgow Outcome Scale (GOS) scores.

RESULTS

There were no statistically significant differences with respect to hospitalized injury, age, or sex distribution between the 2 groups. The incidence of acute kidney injury (AKI) was higher in the control group than in the ICP monitoring group (p < 0.05). The mean mannitol dosage in the ICP monitoring group (443 ± 133 g) was significantly lower than in the control group (820 ± 412 g) (p < 0.01), and the period of mannitol use in the ICP monitoring group (3 ± 3.8 days) was significantly shorter than in the control group (7 ± 2.3 days) (p < 0.01). The 6-month GOS scores in the ICP monitoring group were significantly better than in the control group (p < 0.05). On the 7th, 14th, and 21st days after injury, the plasma cystatin C and Cr concentrations in the ICP-monitoring group were significantly higher than the control group (p < 0.05).

CONCLUSIONS

In patients with moderate and severe TBI, ICP-directed mannitol treatment demonstrated a beneficial effect on reducing the incidence of AKI compared with treatment directed by neurological signs and physiological indicators.

First clinical results with a new telemetric intracranial pressure-monitoring system

BACKGROUND

The knowledge of intracranial pressure (ICP) is the basis of an appropriate neurosurgical treatment. Because clinical, fundoscopic, or radiological data alone are often elusive, a pre- or postoperative long-term monitoring of the ICP itself is desirable.

OBJECTIVE

We describe the first clinical experiences with a new telemetric ICP-monitoring device.

METHODS

The transducer of this telemetric intraparenchymal pressure probe is placed under the galea over the calvaria. ICP can be monitored via a special telemetric reader, placed over the intact skin, and the ICP values are stored in a small portable computer. The system does not require an intensive care environment and can be used in any ward or even at home. The system was successfully applied in 10 patients (age, 3-56 years) in whom raised ICP due to hydrocephalus, shunt dysfunction, endoscopic third ventriculostomy failure, craniostenosis, or pseudotumor cerebri was suspected.

RESULTS

Continuous telemetric monitoring of ICP was performed for 2 to 24 weeks. In 7 patients, increased ICP values could be excluded, and further surgical maneuvers were avoided. In 3 patients, repeated plateaus or continuously raised ICP indicated surgery resulting in a normalization of ICP.

CONCLUSION

This new telemetric system was safe and effective for ICP measurement over a long period, including home monitoring. For the patients, it was easy to handle, and reliable data could be recorded over many weeks. Based on this preliminary experience, the authors consider the new system extremely advantageous in surgical decision making in particularly difficult cases of suspected abnormalities of ICP.

Factors influencing intracranial pressure monitoring guideline compliance and outcome after severe traumatic brain injury

OBJECTIVE

To determine adherence to Brain Trauma Foundation guidelines for intracranial pressure monitoring after severe traumatic brain injury, to investigate if characteristics of patients treated according to guidelines (ICP+) differ from those who were not (ICP-), and whether guideline compliance is related to 6-month outcome.

DESIGN

Observational multicenter study.

PATIENTS

Consecutive severe traumatic brain injury patients (≥16 yrs, n = 265) meeting criteria for intracranial pressure monitoring.

MEASUREMENTS AND MAIN RESULTS

Data on demographics, injury severity, computed tomography findings, and patient management were registered. The Glasgow Outcome Scale Extended was dichotomized into death (Glasgow Outcome Scale Extended = 1) and unfavorable outcome (Glasgow Outcome Scale Extended 1-4). Guideline compliance was 46%. Differences between the monitored and nonmonitored patients included a younger age (median 44 vs. 53 yrs), more abnormal pupillary reactions (52% vs. 32%), and more intracranial pathology (subarachnoid hemorrhage 62% vs. 44%; intraparenchymal lesions 65% vs. 46%) in the ICP+ group. Patients with a total intracranial lesion volume of ~150 mL and a midline shift of ~12 mm were most likely to receive an intracranial pressure monitor and probabilities decreased with smaller and larger lesions and shifts. Furthermore, compliance was low in patients with no (Traumatic Coma Databank score I -10%) visible intracranial pathology. Differences in case-mix resulted in higher a priori probabilities of dying (median 0.51 vs. 0.35, p < .001) and unfavorable outcome (median 0.79 vs. 0.63, p < .001) in the ICP+ group. After correction for baseline and clinical characteristics with a propensity score, intracranial pressure monitoring guideline compliance was not associated with mortality (odds ratio 0.93, 95% confidence interval 0.47-1.85, p = .83) nor with unfavorable outcome (odds ratio 1.81, 95% confidence interval 0.88-3.73, p = .11).

CONCLUSIONS

Guideline noncompliance was most prominent in patients with minor or very large computed tomography abnormalities. Intracranial pressure monitoring was not associated with 6-month outcome, but multiple baseline differences between monitored and nonmonitored patients underline the complex nature of examining the effect of intracranial pressure monitoring in observational studies.

Intracranial Pressure Monitoring: Invasive versus Non-Invasive Methods-A Review

Monitoring of intracranial pressure (ICP) has been used for decades in the fields of neurosurgery and neurology. There are multiple techniques: invasive as well as noninvasive. This paper aims to provide an overview of the advantages and disadvantages of the most common and well-known methods as well as assess whether noninvasive techniques (transcranial Doppler, tympanic membrane displacement, optic nerve sheath diameter, CT scan/MRI and fundoscopy) can be used as reliable alternatives to the invasive techniques (ventriculostomy and microtransducers). Ventriculostomy is considered the gold standard in terms of accurate measurement of pressure, although microtransducers generally are just as accurate. Both invasive techniques are associated with a minor risk of complications such as hemorrhage and infection. Furthermore, zero drift is a problem with selected microtransducers. The non-invasive techniques are without the invasive methods' risk of complication, but fail to measure ICP accurately enough to be used as routine alternatives to invasive measurement. We conclude that invasive measurement is currently the only option for accurate measurement of ICP.

Transcranial Doppler can predict intracranial hypertension in children with severe traumatic brain injuries

PURPOSE

The purpose of this study is to evaluate the accuracy of emergency Transcranial Doppler (TCD) to predict intracranial hypertension and abnormal cerebral perfusion pressure in children with severe traumatic brain injury (TBI).

PATIENTS AND METHODS

A descriptive and retrospective cross-sectional study was designed through data collected from medical records of children with severe TBI (Glasgow coma scale ≤ 8), admitted to a level I pediatric trauma center, between January 2000 and December 2005. Early TCD examination was performed upon admission, and TCD profiles were considered as altered using previously validated threshold values for diastolic velocity (<25 cm/s) and pulsatility index (>1.31) or when no-flow/backflow was detected. Invasive intracranial pressure (ICP) and cerebral perfusion pressure (CPP) monitoring were considered as the gold standard to measure intracranial hypertension (ICH). Statistical analyses compared TCD profiles to increased ICP (≥ 20 mmHg) and abnormal cerebral perfusion pressure (<50 mmHg) at admission.

RESULTS

Non-invasive TCD and ICP monitoring were performed in 117 severe head-injured children. Mean age was 7.6 ± 4.4 years, with a male prevalence (71%). Median initial Glasgow coma scale was 6. TCD had 94% of sensitivity to identify ICH at admission and a negative predict value of 95% to identify normal ICP at admission. Its sensitivity to predict abnormal cerebral perfusion pressure was 80%.

CONCLUSIONS

The high sensitivity of admission TCD to predict ICH and abnormal CPP after trauma demonstrates that TCD is an excellent first-line examination to determine those children who need urgent aggressive treatment and continuous invasive ICP monitoring.

Investigating shunt function using continuous intracranial pressure monitoring in adults: single center experience

OBJECT

Managing symptomatic ventriculoperitoneal shunts with no clear evidence of shunt malfunction either clinically or radiologically can be a difficult task. The aim of this study was to assess intracranial pressure (ICP) monitoring as a method of investigating shunt function.

METHODS

The authors performed a retrospective analysis of 38 continuous ICP monitoring procedures done in patients with ventriculoperitoneal shunts and suspected shunt malfunction.

RESULTS

Thirty-eight procedures were performed in 31 patients between January 2005 and October 2008. Sixteen recordings were normal, 6 revealed overdrainage or low pressure, 11 indicated underdrainage or high pressure, and 5 showed variable shunt function. Based on the findings after 20 procedures (53%), patients were treated conservatively: 4 by readjusting the valve setting and 16 by referral to the headache neurologist for medical treatment. Forty-five percent of the conservatively treated patients improved. Surgical exploration was undertaken following 18 procedures (47%); 72% of the surgically treated patients improved.

CONCLUSIONS

Continuous ICP monitoring using an intraparenchymal probe is a safe and effective method of investigating adult hydrocephalus.

Intracranial pressure monitoring for traumatic brain injury in the modern era

INTRODUCTION

Intracranial pressure (ICP) has become a cornerstone of care in adult and pediatric patients with traumatic brain injury (TBI).

DISCUSSION

Despite the fact that continuous monitoring of ICP in TBI was described almost 60 years ago, there are no randomized trials confirming the benefit of ICP monitoring and treatment in TBI. There is, however, a large body of clinical evidence showing that ICP monitoring influences treatment and leads to better outcomes if part of protocol-driven therapy. However, treatment of ICP has adverse effects, and there are several questions about ICP management that have yet to be definitively answered, particularly in pediatric TBI. This review examines the history and evolution of ICP monitoring, pathophysiological concepts that influence ICP interpretation, ongoing controversies, and the place of ICP monitoring in modern neurocritical care.