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The Cushing response is a pre-terminal sympatho-adrenal systemic response to very high ICP. Animal studies have demonstrated that a moderate rise of ICP yields a reversible pressure-mediated systemic response. Infusion studies are routine procedures to investigate, by infusing CSF space with saline, the cerebrospinal fluid (CSF) biophysics in patients suspected of hydrocephalus. Our study aims at assessing systemic and cerebral haemodynamic changes during moderate rise of ICP in human.

Infusion studies were performed in 34 patients. This is a routine test perform in patients presenting with symptoms of NPH during their pre-shunting assessment. Arterial blood pressure (ABP) and cerebral blood flow velocity (FV) were non-invasively monitored with photoplethysmography and transcranial Doppler.

The rise in ICP (8.2 ± 5.1 mmHg to 25 ± 8.3 mmHg) was followed by a significant rise in ABP (106.6 ± 29.7 mmHg to 115.2 ± 30.1 mmHg), drop in CPP (98.3 ± 29 mmHg to 90.2 ± 30.7 mmHg) and decrease in FV (55.6 ± 17 cm/s to 51.1 ± 16.3 cm/s). Increasing ICP did not alter heart rate (70.4 ± 10.4/min to 70.3 ± 9.1/min) but augmented the heart rate variance (0.046 ± 0.058 to 0.067 ± 0.075/min).

In a population suspected of hydrocephalus, our study demonstrated that a moderate rise of ICP yields a reversible pressure-mediated systemic response, demonstrating an early Cushing response in human and a putative intracranial baroreflex.

This study was designed to monitor secondary insults and their impact on outcomes of patients with hypertensive basal ganglia hemorrhage (HBGH). One hundred and twelve patients with HBGH (male 73, female 39) of age 42 ± 8 years (range from 38 to 57 years) were studied. Operations included craniotomy or trephination drainage with urokinase thrombolysis. Conventional therapies were also given to the patients including the administration of mannitol, crystalloid and colloid solution. In the meantime, blood pressure (MAP), temperature (T) and SaO and other parameters were recorded in the intensive care unit. The ICP values were recorded, and the early clinical outcome was assessed upon discharge according to Glasgow Outcome Scale. Cerebral Perfusion Pressure was calculated as CPP = MAP-MICP. Outcomes in the group without secondary insults were better than that in the group with secondary insults (P < 0.01). No unfavorable outcomes were found in the 59 cases managed by ultra-early surgery whereas 36.1% of the cases operated after 6 hours of onset had unfavorable outcomes. It is concluded that the high incident rate of secondary insults in HICH patients influences outcome. Ultra-early surgery may also contribute to improved quality of survival.

The complications of therapeutic hypothermia sometimes undermine its clinical effects. In this study we investigated the efficacy and safety of therapeutic hypothermia based on analysis of 20 severe head injury cases from 6 institutions treated with therapeutic hypothermia in 1999.

The twenty patients with severe head injury were enrolled prospectively based on the following indications; Glasgow Coma Scale of 7 or less on admission, age 60 or younger, and systric BP over 100 mmHg. A control group consisting of 21 patients with severe head injury met the same criteria but were treated without therapeutic hypothermia in other institutions. Clinical benefit were evaluated by a comparison of clinical result in the two groups defined according to the Glasgow Outcome Scale six months after injury. The hypothermia group was divided into two groups based on a target temperature [mild hypothermia group: 32∼34 °C (n=10); very mild hypothermia group: 35∼36°C (n=10)]. The complication rate, clinical results and the duration of therapeutic hypothermia were analyzed between two groups.

In the hypothermia group, 12 patients obtained a favorable outcome (Good Recovery or Moderate Disabled in GOS) and the mortality rate was 35%. In the control group, however only 5 patients had a favorable outcome and the mortality rate was 57%. Comparison between mild hypothermia and very mild hypothermia groups revealed no difference in clinical outcome. In the hypothermia group, severe pneumonia was seen in three patients, all in the mild hypothermia group with a hypothermic duration of over 120 hours.

Mild hypothermia should be ended within 120 hours to avoid severe complication. When long-lasting therapeutic hypothermia of more than 120 hours is planned, very mild hypothermia is the treatment of choice.

Aim of this study was to examine the hypothesis that only a subgroup of patients with lesser primary brain damage after severe head injury may benefit from therapeutic hypothermia.

We prospectively analysed 72 patients with severe head injury, randomized into groups with (n=37) and without (n=35) hypothermia of 34°C maintained for 72 hours. The influence of hypothermia on ICP, CPP and neurological outcome was analysed in the context of the extent of primary brain damage.

Patients with normothermia and primary lesions (n=17) — values: GCS on admission 5 (median), ICP 18.9 (mean), CPP 73 (mean), GOS 4 (median). Patients with normothermia and extracerebral hematomas (n=20): GCS 4, ICP 16, CPP 71, GOS 3. Patients with hypothermia and primary lesions (n=21): GCS 4,62, ICP 10,81, CPP 78,1, GOS 4. Patients with hypothermia and extracerebral hematomas (n=14): GCS 5, ICP 13.2, CPP 78, GOS 5.

Hypothermia decreased ICP and increased CPP regardless of the type of brain injury. Hypothermia was not able to improve outcome in patients with primary brain lesions but this pilot study suggests that it significantly improves outcome in patients with extracerebral hematomas.

The aim of this study was to determine to what degree hypotension and ICP contribute to the reduction of cerebral perfusion pressure (CPP), particularly in light of the shift in emphasis to CPP management by the use of pressors. The study population consisted of severely head injured patients extracted retrospectively from the Traumatic Coma Data Bank and compared with 139 patients from the Smith Kline component of the American Brain Injury Consortium database where outcome was available. The percentage time that ICP exceeded 20 mm Hg and CPP less than 60 mm Hg was computed for 5 days post injury. At each hour when CPP was less than 60 mm Hg the contribution of raised ICP and low arterial pressure or both was determined. In the first cohort, hypotension was the predominant factor leading to CPP reduction. With use of the CPP concept of treatment, the major contribution to CPP shifted to ICP and arterial hypotension played less of a role. Overall, CPP management has been associated with improved outcome.

It is the general sense that mortality has been decreasing in recent years compared to earlier studies described by the NIH traumatic coma data bank. We studied mortality during the period of 1984 to 1996 to determine if indeed mortality from severe traumatic brain injury was decreasing and to identify factors which might account for the reduction. The study population (N = 1839) consisted of severely head injured patients extracted retrospectively from the TCDB (635), MCV (382), and 822 patients from clinical trial databases conducted in the United States. Mortality was obtained from each of the databases for the age range form 16 to 65. Penetrating injury and treatment groups in the clinical trial databases were excluded. Mortality in the year 1984 equaled 39% and gradually decreased to a level of 27% in 1996. When adjusting for age, motor score and pupil reaction, the mortality of the period from 1984 to 1987 was significantly higher (p < 0:05) than that of the period 1988 to 1996.

During the period 1984 through 1996, mortality from severe brain injury steadily declined. Factors other than age, motor score and pupil reactivity over time are responsible for this reduction. This reduction over time is an important factor for prognostic modeling of TBI.

The Spiegelberg Compliance Device (Spiegelberg KG, Hamburg, Germany) has been available for the automated measurement and calculation of minute by minute intracranial compliance. Widespread practical use has been somewhat limited by the instability of values; especially at low intracranial pressures.

We looked at two aspects of a methodology in an attempt to increase the value of the Spiegelberg device in the clinical setting. Firstly, we discussed the difference in representing measured values as elastance () instead of compliance (); and secondly we proposed the use of an averaging algorithm called the Exponentially Weighted Moving Average (), which could be applied as a flexible method to follow trends and rapid changes in the elastance (or compliance).

Clinical data from sixteen patients were gathered and statistical analysis was focused on three particular aspects, the coefficient of variation which indicates the variability of data values, the correlation between the elastance (or compliance) time series and the underlying ICP signal and the percentage of outliers greater than 2.5 standard deviations from the mean. Our results showed that expressing elastance () instead of compliance () yielded fewer outliers and had a better correlation to ICP, and the method had a better correlation to ICP than the Spiegelberg method.

The aim of this open, descriptive and prospective study was to determine if the new monitoring parameter “continuous intracranial compliance (cICC)” decreases with age in patients with traumatic brain injury (TBI).

30 patients with severe and moderate TBI (Glasgow Coma Scale scorea ≤ 10) contributing to a European multicenter study, organized by the Brain-IT group, underwent computerized monitoring of blood pressure, intracranial pressure (ICP), cerebral perfusion pressure and cICC.

Regression analyses of individual median ICP and median cICC versus patients’ age revealed no significant dependency. Median cICC declined significantly with increasing ICP (when median ICP = 10, 20 and 30 mmHg, cICC = 0.64; 0.56 and 0.42 ml/mmHg respectively, < 0.05). These three ICP groups were then subdivided according to age (0–20, 21–40, 41–60 and 61–80 years). Median cICC declined with age in both high ICP groups (median ICP = 20, 30 mmHg). Percentage cICC values below a set pathological threshold of lower than 0.05 ml/mmHg across the four age groups were 28% (0–20 yrs), 59% (21–40 yrs), 60% (41–60 yrs) and 70% (61–80 yrs) respectively.

The observed phenomenon of decreased intracranial volume challenge compensation with advancing age may contribute to the well-known fact of a worse outcome in elderly patients after TBI.