The Curing Coma Campaign: Framing Initial Scientific Challenges-Proceedings of the First Curing Coma Campaign Scientific Advisory Council Meeting

Coma and disordered consciousness are common manifestations of acute neurological conditions and are among the most pervasive and challenging aspects of treatment in neurocritical care. Gaps exist in patient assessment, outcome prognostication, and treatment directed specifically at improving consciousness and cognitive recovery. In 2019, the Neurocritical Care Society (NCS) launched the Curing Coma Campaign in order to address the "grand challenge" of improving the management of patients with coma and decreased consciousness. One of the first steps was to bring together a Scientific Advisory Council including coma scientists, neurointensivists, neurorehabilitationists, and implementation experts in order to address the current scientific landscape and begin to develop a framework on how to move forward. This manuscript describes the proceedings of the first Curing Coma Campaign Scientific Advisory Council meeting which occurred in conjunction with the NCS Annual Meeting in October 2019 in Vancouver. Specifically, three major pillars were identified which should be considered: endotyping of coma and disorders of consciousness, biomarkers, and proof-of-concept clinical trials. Each is summarized with regard to current approach, benefits to the patient, family, and clinicians, and next steps. Integration of these three pillars will be essential to the success of the Curing Coma Campaign as will expanding the "curing coma community" to ensure broad participation of clinicians, scientists, and patient advocates with the goal of identifying and implementing treatments to fundamentally improve the outcome of patients.

Intrinsic network reactivity differentiates levels of consciousness in comatose patients

OBJECTIVE

We devise a data-driven framework to assess the level of consciousness in etiologically heterogeneous comatose patients using intrinsic dynamical changes of resting-state Electroencephalogram (EEG) signals.

METHODS

EEG signals were collected from 54 comatose patients (GCS ⩽ 8) and 20 control patients (GCS > 8). We analyzed the EEG signals using a new technique, termed Intrinsic Network Reactivity Index (INRI), that aims to assess the overall lability of brain dynamics without the use of extrinsic stimulation. The proposed technique uses three sigma EEG events as a trigger for ensuing changes to the directional derivative of signals across the EEG montage.

RESULTS

The INRI had a positive relationship with GCS and was significantly different between various levels of consciousness. In comparison, classical band-limited power analysis did not show any specific patterns correlated to GCS.

CONCLUSIONS

These findings suggest that reaching low variance EEG activation patterns becomes progressively harder as the level of consciousness of patients deteriorate, and provide a quantitative index based on passive measurements that characterize this change.

SIGNIFICANCE

Our results emphasize the role of intrinsic brain dynamics in assessing the level of consciousness in coma patients and the possibility of employing simple electrophysiological measures to recognize the severity of disorders of consciousness (DOC).

[Unconsciousness and clouded awareness]

Stupor and coma are clinical states in which patients have impaired responsiveness or are unresponsive to external stimulation and are either difficult to arouse or are unarousable. The term stupor refer to states between alertness and coma. An alteration in arousal represents an acute life-threatening emergency, requiring prompt intervention for preservation of life and brain function.

Representing the Glasgow Coma Scale in IT: Proper Specification is Required for Assessment Scales

In healthcare a huge amount of assessment scales and score systems are in use to abbreviate and summarize the results of clinical observations to interpret a patient's condition in a valid and reliable manner. It is challenging to convey the information in a semantic interoperable form to other systems. A bad approach would be to invent individual models for each of them. Within this paper we would like to demonstrate that a generic model is sufficient by demonstrating the realization with the Glasgow Coma Scale.

What is the relationship between the Glasgow coma scale and airway protective reflexes in the Chinese population?

AIM

To describe the relationship of gag and cough reflexes to Glasgow coma score (GCS) in Chinese adults requiring critical care.

METHOD

Prospective observational study of adult patients requiring treatment in the trauma or resuscitation rooms of the Emergency Department, Prince of Wales Hospital, Hong Kong. A long cotton bud to stimulate the posterior pharyngeal wall (gag reflex) and a soft tracheal suction catheter were introduced through the mouth to stimulate the laryngopharynx and elicit the cough reflex. Reflexes were classified as normal, attenuated or absent.

RESULTS

A total of 208 patients were recruited. Reduced gag and cough reflexes were found to be significantly related to reduced GCS (p=0.014 and 0.002, respectively). Of 33 patients with a GCS≤8, 12 (36.4%) had normal gag reflexes and 8 (24.2%) had normal cough reflexes. 23/62 (37.1%) patients with a GCS of 9-14 had absent gag reflexes, and 27 (43.5%) had absent cough reflexes. In patients with a normal GCS, 22.1% (25/113) had absent gag reflexes and 25.7% (29) had absent cough reflexes.

CONCLUSIONS

Our study has shown that in a Chinese population with a wide range of critical illness (but little trauma or intoxication), reduced GCS is significantly related to gag and cough reflexes. However, a considerable proportion of patients with a GCS≤8 have intact airway reflexes and may be capable of maintaining their own airway, whilst many patients with a GCS>8 have impaired airway reflexes and may be at risk of aspiration. This has important implications for airway management decisions.

[Comatose states: etiopathogenesis, experimental studies, treatment of hepatic coma]

The review presents the modern concepts on biochemical mechanisms of processes, that result in comatose states (CS), with emphasis on the search of new therapeutic approaches. CS of various origin causes severe suppression of brain cells functioning and stable unconsciousness. Numerous reasons of various CS are classified into two main groups: primary brain damages (ischemia, tumor, trauma) and secondary damages originating from system injuries in the body (endocrine, toxic e. c.). The most often primary CS is the hypoxic-ischemic one, as result of corresponding encephalopathy. Its mechanism is the brain cells "energy crisis"--because of decreased blood supply or its deficiency by energy substrates or/and by oxygen. Among secondary CS the substantial place takes hepatic coma as a consequence of hepatic encephalopathy in severe liver diseases--cirrhosis, acute liver failure, sharp intoxication. Its main reason is associated with exess of ammonia entering the brain tissue (it accumulates in blood because of lack of its removing by damaged hepatocytes). Ammonia reacts with glutamate in brain astrocytes and the product of this reaction, glutamine, induced osmotic imbalance, that results in change of form and functions of these important brain cells. It induces, in turn, neurons functions damages, changes in neurotransmission and cerebral blood flow and all these may give rise CS. The most of CS studies are carried out in human. Experimental models ofhepatic CS are reproduced mainly in rats, the most often by surgery methods. Other models included administration of thioacetamide or D-galactosamine, sometimes in combination with lipopolysaccharide. In earlier studies ammonia administration together with liver damages by ligation or by CCl4 was used. The main principles of hepatic coma treatment include the care of encephalopathy, detoxification, and liver treatment. Elaboration of new nanodrugs with increased penetration into tissues and cells, in particular, on the base of phospholipid nanoparticles, may increase substantially the therapeuti efficiency. One of such drug is thought to be a new hepatoprotective preparation phosphogliv--nanoparticles of soy phosphatidylcholine with glycyrrhizic acid. It is supposed, that the further development of phospholipid nanoforms, with minimal particle sizes, may reveal the more action in CS treatment.

[Coma criterion and classification standard of mild and moderate traumatic brain injury in rats]

OBJECTIVE

To set up a classification standard of mild and moderate traumatic brain injury, for the purpose of reliable data comparison derived from different laboratories.

METHODS

Traumatic brain injury (TBI) in rats was prepared by using a metallic pendulum-striker device. After injury, five variable parameters including the time of apnea and the areflexia, time of corneal reflex, external auditory canal stung reaction, body-righting reflex and needling reaction were determined and scored by using rat coma criterion. These data were judged and classified into mild and moderate head injury by brain patho-anatomy changes. Then the data were used to set up a multivariate discriminate equation.

RESULTS

The distinguished probability of mild and moderate TBI according to actual direct measured value and the criterion were 88.9% and 91.9%, respectively.

CONCLUSION

This method is able to classify mild and moderate TBI in rats.

Coagulation, coma, and outcome in bacterial meningitis--an observational study of 38 adult cases

OBJECTIVES

The purpose of this study was to evaluate the epidemiology of intravascular coagulation in bacterial meningitis and to recognise the associations with disease severity and outcome.

METHODS

Thirty-eight consecutively admitted adult patients with microbiologically proven bacterial meningitis were observed prospectively for platelets count (PLT), platelets-decline (dPLT), prothrombin ratio (PTr), INR, and D-dimer levels during the first three days in relation to disease severity (Glasgow Coma Scale--GCS, APACHE-III) and outcome (Glasgow Outcome Scale--GOS).

RESULTS

The prevalence of activated coagulation measured by abnormal laboratory results varied respectively: PTr--30%, INR--36%, PLT--38%, dPLT--50%, and D-dimer--88%. Patients with GCS <9 at admission presented with laboratory results suggesting triggered coagulation: dPLT 48 vs. 15%/day (p=0.0246), INR 1.6 vs. 1.12 (p=0.0014), PTr 76 vs. 93% (p=0.0020). An unfavourable outcome (GOS 1-4) was observed in 42% of patients and was associated with: PLT <170 or >265 G/L (OR--24.4; p=0.0006), PTr <82% (OR--5.00; p=0.0388), INR >1.1 (OR--5.04; 0.0336), and D-dimer >850 ng/ml (OR--24.0; p=0.0033).

CONCLUSIONS

Coagulation was activated in a majority of patients with bacterial meningitis and related to coma and unfavourable outcome.

Méthodes d’étude clinique des traumatismes crâniens

The development of data processing techniques has enabled the establishment of large databanks on brain injury. Clinical features are described with clinical scoring scales, the main one being the Glasgow Coma Scale. Three types of patient response are analyzed: eye opening, oral answers, active muscular reaction. The advantages and disadvantages of each are presented. Others scales have been proposed but are not in common use. Several classifications have been established combining depth and length of coma. Post-traumatic amnesia, i.e. the period of time running from the injury to recovery of anterograde memory, constitutes the most important parameter in the classification of these injuries. Generally, three gravity grades are used: mild, moderate and severe brain injuries. Knowledge of the prognosis is essential for determining the most appropriate medical care and is directly related to the quality of the collected data. Five outcome categories can be described.

Electroencephalographic Assessment of Coma

SUMMARY

Altered mental status ranging from confusion to deep unresponsiveness can be described as coma. Electroencephalography is an important tool in assessing comatose patients. Some EEG patterns are seen with lighter stages of coma and have a good prognosis, whereas others are seen in deep, often irreversible coma. These EEG patterns carry a much more grave prognosis. This paper discusses the various EEG features seen in coma, ranging from intermittent rhythmic delta activity to electrocerebral inactivity. A discussion regarding etiology and prognosis is presented after the EEG pattern is described in detail. Special EEG features, such as alpha coma, beta coma, spindle coma, etc., are discussed toward the end.

Hypoglycaemia in a Nigerian paediatric emergency ward

Hypoglycaemia is a common problem in paediatric emergency admissions. It has not received enough attention in Nigeria. It has been shown to complicate many childhood illnesses. This study aimed to determine the prevalence of hypoglycaemia in paediatric emergency admissions, describe clinical factors that commonly predispose to it and investigate its effect on outcome of management. Three-hundred and ninety-two consecutively admitted patients were studied. Two milliliters of blood was obtained from each patient for plasma glucose determination. Hypoglycaemia was defined as plasma glucose <2.5 mmol/l (<45 mg/dl). Out of these 392, twenty-five (25) of them were hypoglycaemic giving a prevalence of hypoglycaemia to be 6.4 per cent in our emergency ward. Hypoglycaemia was found to be associated commonly with severe malaria, septicaemia, pneumonia, and protein energy malnutrition. Interval of last meal and unconsciousness were the only two significant associated factors to hypoglycaemia. However, the likelihood of hypoglycaemia is increased with night admissions and prolonged duration of illness before admissions. Presence of hypoglycaemia at admission was also found to be significantly associated with death and dying within 24 hours of admission. The prevalence of hypoglycaemia was found to be 6.4 per cent. It was found to complicate many childhood illnesses and it is associated with a higher mortality. It should be suspected in all very ill children, particularly when they are unconscious and have not eaten for over 12 hours.

Zerebrale Funktionen bei hirngeschädigten Patienten

Comatose, vegetative, minimally conscious or locked-in patients represent a problem in terms of diagnosis, prognosis, treatment and everyday management at the intensive care unit. The evaluation of possible cognitive functions in these patients is difficult because voluntary movements may be very small, inconsistent and easily exhausted. Functional neuroimaging cannot replace the clinical assessment of patients with altered states of consciousness. Nevertheless, it can describe objectively how deviant from normal the cerebral activity is and its regional distribution at rest and under various conditions of stimulation. The quantification of brain activity differentiates patients who sometimes only differ by a brief and incomplete blink of an eye. In the present paper, we will first try to define consciousness as it can be assessed at the patient's bedside. We then review the major clinical entities of altered states of consciousness encountered in the intensive care unit. Finally, we discuss the functional neuroanatomy of these conditions as assessed by positron emission tomography (PET) scanning.

Evaluation of coma and brain death

Coma is a nonspecific sign of widespread central nervous system impairment resulting from various metabolic and structural etiologies. The rapid recognition of this neurologic emergency and results from the history, physical examination, and early investigative studies are key to the identification and treatment of its underlying cause. The prognosis for recovery depends greatly on the underlying etiology as well as on its optimal treatment, which seeks to preserve neurologic function and maximize the potential for recovery by reversing the primary cause of brain injury, if known, and preventing secondary brain injury from anoxia, ischemia, hypoglycemia, cerebral edema, seizures, infections, and electrolyte and temperature disturbances. Brain death must be diagnosed with similar care and precision, and families approached compassionately about the diagnosis and their decisions regarding organ donation.

[Point systems for evaluating coma in patients with injuries of the central nervous system (CNS)]

Paper reviews various coma scales which are used to monitor consciousness after sustaining severe injuries of CNS. Glasgow Coma Scale, at present the most frequently used, was compared to recently developed scales, which are more useful for monitoring persistent comas, allows to evaluate discrete changes in patient's state more precisely and to predict the outcome. The necessity of evoked potentials' measurements, such as Trigeminal-Auditory Glasgow (Coma Scale) has been stressed.

The prognostic value of evoked responses from primary somatosensory and auditory cortex in comatose patients

OBJECTIVE

To evaluate somatosensory and auditory primary cortices using somatosensory evoked potentials (SEPs) and middle latency auditory evoked potentials (MLAEPs) in the prognosis of return to consciousness in comatose patients.

METHODS

SEPs and MLAEPs were recorded in 131 severe comatose patients. Latencies and amplitudes were measured. Coma had been caused by transient cardiac arrest (n=49), traumatic brain injury (n=22), stroke (n=45), complications of neurosurgery (n=12) and encephalitis (n=3). One month after the onset of coma patients were classified as awake, still comatose or dead. Three months after (M3), they were classified into one of the 5 categories of the Glasgow outcome scale (GOS).

RESULTS

At M3, 41.2% were dead, 47.3% were conscious (GOS 3-5) and 11.5% had not recovered consciousness. None of the patients in whom somatosensory N20 and auditory Pa were absent did return to consciousness and in the post-anoxic group, reduced cortical amplitude too was always associated with bad outcome. Conversely, N20 and Pa were present, respectively, in 33/69 and 34/69 patients who did not recover.

CONCLUSIONS

The prognostic value of SEPs and MLAEPs in comatose patients depends on the cause of coma. Measurement of response amplitudes is informative. Abolition of cortical SEPs and/or cortical MLAEPs precludes post-anoxic comatose patients from returning to consciousness (100% specificity). In any case, the presence of short latency cortical somatosensory or auditory components is not a guarantee for return to consciousness. Late components should then be recorded.

[How can we define the modalities and clinical levels of coma to wakefulness?]

OBJECTIVE

The starting point of the French conference of consensus concerning arousal after coma was to answer the following question: "How can we define the ways of going from coma to arousal and their clinical levels?

MATERIALS AND METHOD

A team of readers have picked up in the literature one hundred and fifty papers, out of which fifty six have been analysed.

RESULTS

From this analysis, three points emerged: The concepts of coma and arousal; The conditions of evolution from coma to arousal; Various groups of patients depending on their expressing arousal. One could not find any consensual model concerning the different ways of going from coma to arousal. The variability of the technics and the changing validity of all scores did not allow the conditions of arousal to reach a satisfactory level of proof. The Glasgow Coma Scale (GCS) is the recognised standard for severe wakefulness' impairment, but it is not sensitive enough while patients' arousing. The Glasgow Outcome Scale (GOS) takes into account the patients' situations far later and does not include situations such as Minimally Conscious States (MCS). That's why we face multiple scores, either ordinal, or categorial, all tending to evaluate the slow levels of arousal.

CONCLUSION

Clinical findings concerning arousal are to be completed by non-clinical data. This would be greatly helpful to define appropriate management concerning individualized groups of patients. At this stage, another challenge for clinicians is to make the difference between emerging wakefulness and growing conscious activity.

Evaluating the comatose patient. Rapid neurologic assessment is key to appropriate management

Coma is defined as a sleeplike state in which the patient is unresponsive to self and the environment. Coma should be distinguished from the persistent vegetative state and locked-in syndrome. It is important to obtain a carefully taken history from eyewitnesses and to perform a rapid neurologic examination focusing on pupillary responses, eye movements, and motor responses. Pupils reactive to light usually indicate metabolic or medical coma; cerebellar infarction or hemorrhage is a notable exception. A pupil unreactive to light often points to a structural brain lesion and the need for urgent neurosurgical consultation. The prognosis for coma depends on the cause.

Classification of severe head injury based on magnetic resonance imaging

OBJECT

In 1991 a new pioneering classification of severe head injuries had been proposed, based on CT findings. Unfortunately CT cannot visualise all lesions. Especially brain stem lesions may escape CT in spite of modern equipment, but may be demonstrated by MRI. The high incidence of CT negative but MRI positive posttraumatic brain stem lesions has already been demonstrated in a limited number of cases. A statistically significant evaluation is still missing. Therefore we have investigated a series of 102 comatose patients, in whom a statistical evaluation of MRI findings and their correlation with mortality and outcome of survivors was possible.

PATIENTS AND METHODS

MRI was obtained within 8 days after servere head injury in 102 patients with a minimum of 24 hours of coma. The location of the lesions. identified by a neuroradiologist who was unaware of the clinical findings, was correlated with mortality, outcome of surviors and duration of coma. The correlation was analysed statistically. Follow-up ranged from 3 months to 3 years with a mean of 22 months. Four groups of lesions gave significant correlations: Grade I lesions were lesions of the hemispheres only; Grade II lesions were unilateral lesions of the brain stem at any level with or without supratentorial lesions; Grade III lesions were bilateral lesions of the mesencephalon with or without supratentorial lesions. Grade IV lesions were bilateral lesion of the pons with or without any of the foregoing lesions of lesser grades.

RESULTS

Mortality increased from 14% in grade I lesions to 100% in grade IV lesions. The Glasgow outcome score differed significantly for each grade. The mean duration of coma increased from 3 days in grade I patients to 13 days in grade III. The correlations between the lesions grade I to IV with mortality, outcome of survivors and duration of coma were highly significant.

CONCLUSION

The statistically significant correlations between the 4 groups of severe head injury patients, as identified by MRI, with mortality and outcome of survivors justify a new classification based on early MRI findings.

Neuropsychological outcome in relation to the traumatic coma data bank classification of computed tomography imaging

The Traumatic Coma Data Bank (TCDB) classification of CT (computed tomography) scan has been related to the general outcome and intracranial pressure evolution. Our aim was to analyse the relationship of this classification with neuropsychological outcome and late indices of ventricular dilatation. Fifty-seven patients with a moderate or severe head injury (mean admission Glasgow Coma Scale Score, 7.7) were studied from 122 consecutive cases. There were 49 males and 8 females (mean age, 27.7 years). Subjects were classified into TCDB categories on the basis of their most serious acute CT scan finding. From the last control CT scan image, performed at a mean of 6.12 months postinjury, several measures of ventricular dilatation were calculated. Neuropsychological assessment at 6-month included tests of verbal and visual memory, visuoconstructive functions, fine motor speed, and frontal lobe functions. Patients with diffuse injury type I showed better neuropsychological outcome than patients with more severe diffuse injuries and those with mass lesions. Within the diffuse injury groups, the degree of diffuse damage was related to measures of verbal memory and attention and cognitive flexibility. Ventricular enlargement was more evident in patients with mass lesions and it decreased in the remaining groups as the severity of diffuse injury diminished. These results show that there is a relationship between acute intracranial lesion diagnosis according to TCDB classification and neuropsychological results and ventricular dilatation indices at 6 months postinjury.

Flumazenil in the treatment of acute hepatic encephalopathy in cirrhotic patients: a double blind randomized placebo controlled study

AIMS

The aim of this study was to evaluate the effects of flumazenil on hepatic encephalopathy in patients with liver cirrhosis.

PATIENTS AND METHODS

. In the double blind randomized, placebo controlled study, 54 patients with hepatic encephalopathy grade III-IV were randomly assigned to receive either flumazenil 2 mg iv (group A) or placebo (group B); conventional treatment with branched-chain amino acid, saline, glucose, and lactulose was administered in both groups. A 24-hour observation period was established. Clinical improvement was defined as a 3 point decrease in the Glasgow coma score at any time within 24 hours.

RESULTS

Clinical improvement was obtained in 22/28 patients in group A and in 14/26 in group B (p<0.05); improvement was observed within the first six hours in 21/22 patients in group A and only in 3/14 in group B. Mortality rate was not different between group A and B; however, all 6 non-responders in group A and only 5 out of 12 in group B died within 24 hours. Among patients with post-bleeding encephalopathy, 11 out of 17 in group A and only 2 out of 14 in group B improved (p<0.001).

CONCLUSIONS

Flumazenil may exert a beneficial effect in a subset of patients with acute hepatic encephalopathy; encephalopathy associated with bleeding is more likely to respond to flumazenil; responders to the treatment usually improve within the first 6 hours while lack of response usually represents a bad prognostic sign.

Excision for the treatment of periarticular ossification of the knee in patients who have a traumatic brain injury

BACKGROUND

Patients who are comatose after a traumatic brain injury often have heterotopic periarticular ossification that can be treated with excision to improve the range of motion of the joint.

METHODS

Areas of periarticular ossification were resected at an average of twenty-three months after recovery from a coma in seven knees of five patients who had a traumatic brain injury. Before the procedure, all of the knees were fixed in a flexed position that ranged from 10 to 40 degrees and they had a painful arc of motion that ranged from 20 to 70 degrees of flexion. None of the patients could walk, and some of them could barely sit in a wheelchair. At the end of the operation, the arc of motion was markedly improved in all of the knees (0 to 130 degrees in three knees, 0 to 120 degrees in three, and 10 to 120 degrees in one). In an attempt to prevent postoperative loss of motion and recurrence of the ossification, continuous passive motion was applied to the involved knee for six weeks before a full rehabilitation program was started. The latest follow-up evaluation was at an average of thirty-four months (range, twenty-five to sixty months).

RESULTS

At the time of follow-up, all of the patients could walk and all of the knees were pain-free. One knee had an arc of flexion of 0 to 90 degrees; two, an arc of 10 to 100 degrees; one, an arc of 5 to 110 degrees; two, an arc of 0 to 120 degrees; and one, an arc of 0 to 130 degrees. Ossification did not recur in any of the knees.

CONCLUSIONS

Patients with good neuromuscular control had the best general functional result. The routine use of a continuous-passive-motion machine was associated with no recurrence of ossification, and there was some late loss of motion after its use was discontinued.

Relation of body position at the time of discovery with suspected aspiration pneumonia in poisoned comatose patients

OBJECTIVE

The left lateral decubitus position is generally accepted as the position of choice to protect against aspiration pneumonia in comatose poisoned patients. We studied the relationship between initial body position during coma and subsequent development of suspected aspiration pneumonia (SAP).

DESIGN

Observational, descriptive study.

SETTING

Toxicology intensive care unit in a university hospital.

PATIENTS

Acutely poisoned comatose patients admitted to our intensive care unit.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Glasgow Coma Scale score (GCS) and body position were recorded in poisoned patients on discovery. Chest radiographs were examined for infiltrates suggesting SAP within 24 hrs of hospitalization. The prone positioned patients had a lower incidence of SAP than patients in the lateral decubitus and supine positions, despite similar GCS scores. Patients in the semi-recumbent position had an incidence of SAP similar to prone patients, but with higher GCS values.

CONCLUSIONS

The prone position appears to be associated with a lower incidence of SAP than the lateral decubitus position in comatose poisoned patients.

Incidence of intracranial hypertension after severe head injury: a prospective study using the Traumatic Coma Data Bank classification

Intracranial hypertension (ICH) is a frequent finding in patients with a severe head injury. High intracranial pressure (ICP) has been associated with certain computerized tomography (CT) abnormalities. The classification proposed by Marshall et al. based on CT scan findings, uses the status of the mesencephalic cisterns, the degree of midline shift, and the presence or absence of focal lesions to categorize the patients into different prognostic groups. Our aim in this study was to analyze the ICP evolution pattern in the different groups of lesions of this classification.

PATIENTS AND METHODS

We present the results of a prospective study in 94 patients with severe head injury, in whom ICP was monitored for at least 6 hours. ICP evolution was classified into three different categories: 1) ICP always < 20 mm Hg, 2) Intracranial hypertension at some time during monitoring, but controlled by medical or surgical treatment, 3) Uncontrollable ICP. The ICP pattern was correlated with the final CT diagnostic category.

CONCLUSIONS

3 patients had a normal CT scan, and none of them presented intracranial hypertension. In diffuse injury type II, the ICP evolution may be quite different. Patients with bilateral brain swelling (Diffuse Injury III) have a high risk of increased ICP (63.2%). Although in our study the frequency of Diffuse Injury IV was low, all patients in this category had a refractory ICP. In the category of evacuated mass lesions, two thirds of the patients presented an intracranial hypertension. In one third, ICP was refractory to treatment. 85% of patients with a non-evacuated mass lesion showed an increased ICP.

Attempt to establish a classification of patients suffering from coma and admitted to a hospital structure for short or medium term treatment: medical aspects and costs of hospital care

We dispose of a database, constituted between 1987 and 1993, containing medical and cost information concerning 515 patients suffering from coma and admitted, after a period of resuscitation, to a French hospital establishment--Etablissement Hélio-Marin of Berck-sur-Mer (EHMB)--for short and medium term treatment, between 1974 and 1986. From this base, which contains demographic and clinical data (age, sex, condition upon admission, duration of consciousness disorders, Glasgow Outcome Scale (GOS) upon discharge) we devised a hierarchical classification analysis following a factorial analysis of multiple correspondences, on 2 sets: a sample of 515 patients (all causes of coma being merged) and a sample of 266 patients suffering from brain injuries. Four groups were determined for each typology. These groups were first described on the basis of the variables used for their construction, and later by considering other available variables: origin of coma, duration of stay at EHMB, future evolution of patients and cost of treatment (cost of specific care, average daily cost, total cost of hospitalization). Thus, typical clinical situations were identified in each classification, depending on age of patient, origin of coma and condition upon admission. These situations led to extremely different treatment costs (ratio from 1 to 5 in the general typology and 1 to 2.85 in the classification of brain injuries.

An electroencephalographic classification for coma

BACKGROUND

The assessment of thalamocortical function in comatose patients in the intensive care unit (ICU) can be difficult to determine. Since the electroencephalogram (EEG) affords such assessment, we have developed an EEG classification for comatose patients in our general ICU.

METHODS

One hundred EEGs were classified in a blinded fashion by two EEGers, using our method and that of Synek. Interobserver agreement was assessed using kappa score determination.

RESULTS

Kappa scores were 0.90 for our system and 0.75 for the Synek system. (The Kappa score represents the inter-rater agreement that is beyond chance; 0.90 is almost perfect agreement, while 0.75 is substantial agreement).

CONCLUSION

Our system for classifying EEGs in comatose patients has a higher interobserver reliability than one that was previously published. This EEG classification scheme should be useful in clinical electrophysiological research involving ICU patients, allowing for internal consistency and comparisons among centres.

[Correlation of carbamazepine levels in blood with clinical poisoning states, evaluated with the help of the APACHE II system and the Matthew coma scale]

Acute carbamazepine (CBZ) poisoning occurs recently quite often. Symptomatology of poisoning is variable but usually various degrees of consciousness impairment prevail. 77 patients (36 women and 41 man, mean age 31.5) were hospitalized last two years in this Centre. Clinical condition was evaluated in a regular descriptive way, classifying the degree of coma according to the Matthew scale but also by calculating the scores according to APACHE II and TOXSCORE. Serum CBZ was measured. A slight falling trend was found of the relation of the serum CBZ in the range 6-37.8 micrograms/ml (38 micrograms/ml = median) to APACHE II score and the TOXSCORE and slight rising trend of the relation of the serum CBZ to the degree of coma. The significance of this trend rose essentially at the serum CBZ levels of more than the median 38 micrograms/ml. The causes of the non significant correlation of serum CBZ (in particularly range) to the clinical condition is discussed. The individuals factors of the patient and possible effect of other, unknown drugs taken together with CBZ seem to play a minor role at the concentrations above 38 micrograms/ml. A very precise correlation has been found at the serum concentrations exceeding 40 micrograms/ml.

Near-drowning and drowning classification: a proposal to stratify mortality based on the analysis of 1,831 cases

STUDY OBJECTIVE

To establish an updated classification for near-drowning and drowning (ND/D) according to severity, based on mortality rate of the subgroups.

MATERIALS AND METHODS

We reviewed 41,279 cases of predominantly sea water rescues from the coastal area of Rio de Janeiro City, Brazil, from 1972 to 1991. Of this total, 2,304 cases (5.5%) were referred to the Near-Drowning Recuperation Center, and this group was used as the study database. At the accident site, the following clinical parameters were recorded: presence of breathing, arterial pulse, pulmonary auscultation, and arterial BP. Cases lacking records of clinical parameters were not studied. The ND/D were classified in six subgroups: grade 1--normal pulmonary auscultation with coughing; grade 2--abnormal pulmonary auscultation with rales in some pulmonary fields; grade 3--pulmonary auscultation of acute pulmonary edema without arterial hypotension; grade 4--pulmonary auscultation of acute pulmonary edema with arterial hypotension; grade 5--isolated respiratory arrest; and grade 6--cardiopulmonary arrest.

RESULTS

From 2,304 cases in the database, 1,831 cases presented all clinical parameters recorded and were selected for classification. From these 1,831 cases, 1,189 (65%) were classified as grade 1 (mortality=0%); 338 (18.4%) as grade 2 (mortality=0.6%); 58 (3.2%) as grade 3 (mortality=5.2%); 36 (2%) as grade 4 (mortality=19.4%); 25 (1.4%) as grade 5 (mortality=44%); and 185 (10%) as grade 6 (mortality=93%) (p<0.000001).

CONCLUSION

The study revealed that it is possible to establish six subgroups based on mortality rate by applying clinical criteria obtained from first-aid observations. These subgroups constitute the basis of a new classification.

Methylphenidate in the treatment of coma

While there is significant morbidity and mortality involving patients in semicomatose and comatose states, the care of such patients has traditionally been limited to supportive measures. We report two cases of patients treated with methylphenidate hydrochloride: the first, a patient in a semicomatose state resulting from traumatic brain injury, and the second, a patient in a comatose state secondary to a subdural hematoma that occurred after a fall. Treatment with methylphenidate may provide neurostimulations by augmenting the activity of injured neuronal tissue within the reticular activating system, and by amplifying the net effect of the reduced number of viable neurons. Methylphenidate is a low-cost, potentially efficacious intervention for reducing the duration of comas, for preventing life-threatening and costly complications of prolonged unconsciousness, and for promoting early ambulation and recovery. Further research using more rigorous research designs to ascertain the effectiveness of methylphenidate in the treatment of patients in semicomatose and comatose states is needed.

Symptomatic intracranial haemorrhage in acute nonlymphoblastic leukaemia: analysis of CT and autopsy findings

We studied the CT and autopsy findings in patients with symptomatic intracranial haemorrhage (ICH) in acute nonlymphoblastic leukaemia (ANLL). From 1982 to 1994, 38 (20%) of 194 patients with ANLL were diagnosed as having ICH, by CT in 17 patients, by autopsy in 11 and by both examinations in 10. Intracerebral haemorrhage occurred in 30 patients. Twenty-four patients with subcortical haemorrhage were classified into three types: a single haematoma (7), clustered multifocal haematomas (11), and separated multifocal haematomas (6). Subarachnoid haemorrhage (SAH) occurred in 22 patients; 15 with subcortical haemorrhage, 1 with subdural haemorrhage (SDH) and 6 without any other ICH. SDH was also found in 4 patients with parenchymal haemorrhage or SAH or both. Concurrent, multiple haemorrhages consisting of various combinations of intracerebral haemorrhage, SAH and SDH are characteristic of ICH in ANLL. Multiple or confluent haematomas occur preferentially in subcortical brain.

[The comatose patient: initial considerations and measures]

The aim of assessing the emergency patient's threshold of consciousness is to diagnose and manage reversible and treatable conditions fast and effectively. Diagnosis and treatment procedures can be summarized on three levels. First assessment and treatment of hypoxia and shock, second: differentiation of types of coma, in order to decide further treatment measures and the choice of hospital admittance, and third: initiation of antidotes and other appropriate preclinical therapies.

The Coma Exit Chart: assessing the patient in prolonged coma and the vegetative state

The patient who remains in prolonged coma or in the vegetative state presents major problems in medicine, ethics and resource economics. Diagnosis and decision making are often difficult. A Coma Exit Chart can be developed using the parameters of the Glasgow Coma Scale to measure the exiting of the patient from prolonged coma or the vegetative state.

Motor profile of patients in minimally responsive and persistent vegetative states

The purpose of this descriptive clinical study is to document the motor characteristics of patients in minimally responsive and persistent vegetative states. Twelve subjects, presenting a prolonged altered state of consciousness (x = 7.82 years, range 2-27), aged 27-78 years (x = 50, SD = 15.26) were evaluated, using standardized protocols, on the following variables: passive range of motion, observed movements, reflexes, tonus, postural status and reactions. The subjects' level of awareness and responsivity were measured with the Coma/Near Coma (CNC) scale at each of the three data collection sessions. While group CNC scores were stable over the three sessions, fluctuations in the level of awareness of individual subjects was recorded, confirming the heterogeneity of this clientele. Abnormal primitive reflexes were present in all subjects, with the flexor withdrawal (75%), the tonic labyrinthine (36%) and the body-on-body righting reaction (25%) being the most frequently observed. All subjects presented altered tonus, considerable posturing and varied degrees of reduced range of joint motion. A range of abnormal (e.g. chewing, clonus) and normal patterned (e.g. bridging, scratching) movement behaviours was recorded, but these did not translate into functional use, such as rolling. Collectively, the findings stress the complexity of the motor profile of patients in minimally responsive and vegetative states, and suggest the need for physiotherapists to become more actively involved in the evaluation and treatment of this clientele.

Therapeutic Intervention Scoring System used in the care of patients in pentobarbital-induced coma to determine nurse-patient ratios

BACKGROUND

Critical care patients generally require extensive interventions, thereby consuming a large percentage of healthcare resources. Induced pentobarbital coma for the management of increased intracranial pressure is one such intervention, required to maintain patient stability. Quantification of these interventions, as well as the amount of nursing work required, has not been addressed in the literature.

OBJECTIVE

To use the Therapeutic Intervention Scoring System to analyze and quantify how interventions affect nurse-patient ratios in the management of patients in pentobarbital coma for refractory increased intracranial pressure.

METHODS

The medical records of patients with subarachnoid hemorrhage from aneurysmal rupture and subsequent increased intracranial pressure, in whom pentobarbital coma was salvage therapy, were reviewed retrospectively. The Therapeutic Intervention Scoring System was used to quantify the number of interventions required before, during, and after coma induction. The data were analyzed and daily Therapeutic Intervention Scoring System scores correlated with serum pentobarbital levels. Typically, a critical care nurse can manage a patient caseload of 40 to 50 Therapeutic Intervention Scoring System points. By quantifying the interventions, the score reflected the amount of care required to manage the patient in barbiturate coma.

RESULTS

The intensity of interventions correlated with the level of coma, length of time in coma, and associated complications.

CONCLUSIONS

The scores indicated the intensity of interventions used in pentobarbital coma and the use of resources. Nursing care and complications involved with this therapy were quantified and nurse-patient ratios were established.

Inter-observer agreement of the assessment of coma scales and brainstem signs in non-traumatic coma

The authors evaluated the inter-observer agreement between two experienced clinicians examining 19 unconscious children who were not paralysed or ventilated. Inter-observer reliability was assessed by proportion of agreement, disagreement rate and kappa statistics. Corneal reflexes, pupillary responses to light and motor responses were the most reliably elicited. Reduction of the number of categories improved inter-observer agreement. Some of the disagreement may be attributed to changes in the child's condition during the period of assessment. There was more agreement about the five-category 0-IV scale than the summated Adelaide (10-category) and Jacobi (13-category) scales. The ability of these scales to follow changes in the patient's condition and to predict outcome needs to be evaluated in a prospective trial.

[Causes of disorders of consciousness in internal medicine intensive care units]

The present study on 5330 patients admitted to the internal intensive care unit over the five year period (1990-1994) indicated that consciousness disorders are most frequently associated with poisoning. On admission, the state of consciousness of 665 of these 5330 patients was retrospectively evaluated. Poisoning by drugs was most common among intoxications (93 patients of 154 cases of poisoning). Coma, which is the most severe manifestation of consciousness disorder, occurred very often in these patients. Poisoning caused by other agents was connected with other forms of consciousness disorders. Low Glasgow Coma Score (GCS) was a severe predictor, while the number of deaths among patients with GCS > 10 was low. Sepsis was the next most common cause of consciousness disorder among our patients (88 patients). Death rate in these patients was high, amounting to almost 50%, regardless of GCS on admission, suggesting that the severity of main event determines the outcome. Glycemia disorders, including hypoglycemia, hyperglycemia as well as hyperosmotic state, did not result in lethal outcome, regardless of GCS on admission. The highest death rate was registered in patients with cardiopulmonary arrest and lowest GCS on admission. Patients with cardiogenic shock, despite high GCS on admission, had high death rate.

Level of consciousness and age as prognostic factors in aneurysmal SAH

The prognostic value of the level of consciousness and the patient's age for the outcome of aneurysmal subarachnoid haemorrhage (SAH) is studied in 74 patients admitted on day (D) 0 to D3 after aneurysm rupture. For the level of consciousness three groups of patients are compared: grade I+II (alert patients), grade III+IV (drowsy patients), and grade V (comatose patients). For the age, two groups are compared: patients aged under 50, and patients aged 50 and over. The timing of surgery was: D0-D3 51%, D4-D6 20%, D7 and later 18%, and No surgery 11%. The overall management results were: Good (satisfactory result) 43%, Fair (moderately disabled) 18%, Poor (severely disabled+vegetative survival) 19%, and Death 20%. The outcome was strongly related to the level of consciousness, the rates of Good result decreasing from 71% (grades I-II) to 14% (grades III-IV) and to zero (grade V), and the mortality rates increasing respectively from 5% to 14% and 61%. The relationship between outcome and age was less marked: 54% Good result under 50 and 30% over 50. Out of the Grade V group, 56% could be operated upon and 44% died before surgery. No patient from the other two groups died before surgery. The literature concerning the Grading Systems published so far and the various prognostic factors are discussed.

Cranial computed tomography scans in children after minimal head injury with loss of consciousness

STUDY OBJECTIVE

To assess the need for cranial computed tomography (CT) in the emergency department evaluation of children with Glasgow Coma Scale (GCS) score of 15 after mild head injury with loss of consciousness.

DESIGN

Retrospective case series of children aged 2 to 17 years with documented loss of consciousness after head injury from January 1, 1988, to July 31, 1992. All had a GCS score of 15 on initial ED evaluation and were further categorized according to physical examination findings, neurologic status, and whether the head injury was isolated or nonisolated. Recursive partitioning was used to identify variables predictive of the presence and absence of intracranial hemorrhage.

SETTING

ED in two settings: a regional tertiary care trauma center and a community children's hospital.

RESULTS

Of the 185 patients who met study criteria, 17 had evidence of depressed or basilar skull fractures on physical examination or had a ventriculoperitoneal shunt in place before head injury. In the remaining 168 patients, recursive partitioning identified two variables (neurologic status and head injury type) associated with intracranial hemorrhage. Overall, 12 of 168 patients (7%) had intracranial bleeding. However, none of the 49 neurologically normal children with isolated head injury had intracranial hemorrhage (95% confidence interval, 0.0 to 6.0).

CONCLUSION

The prevalence of intracranial hemorrhage in children with mild closed-head injury appears to vary with the presence of neurologic abnormalities and other noncranial injuries. After isolated head injury with loss of consciousness, children older than 2 years who are neurologically normal and without signs of depressed or basilar skull fracture may be discharged home from the ED without a cranial CT scan after careful physical examination alone.

[An uni-dimensional ordinal coma scale]

With the introduction and wide acceptance of the Glasgow coma scale, some progress was made in 1980s. Various types of coma scale were offered from different centers of the world for assessing coma and impaired consciousness. The existing coma scales may be divided into two main categories: (1) multi-dimensional scale, e.g., Glasgow coma scale (GCS), Glasgow-Liege coma scale (G-LCS), Maryland coma scale (MCS); and (2) uni-dimensional scale, e.g., Edinburgh-2 coma scale (E2CS). There is evidence that the uni-dimensional coma scale is better than the multi-dimensional coma scale. The major drawbacks in the multi-dimensional coma scale is the total figure of coma level must be envisaged stereographially. The sum of scores of three dimensions of GCS, as in a multi-dimensional scale, consists of 13 levels from 3 through 15, but the numbers of simple combination constituting each score are considerable. No. 9 in GCS scale may be made up of 18 combinations. E2CS, as an uni-dimensional scale, seems to be an improvement over GCS. On the basis of comparison between two main categories of coma scale and considering the shortcomings of E2CS, a modified uni-dimensional ordinal coma scale called "Chengdu-1 Coma scale" (C1CS) was proposed and applied for evaluating the depth of coma and for prognosticating the patients' outcome. This study was based on 98 acutely head-injured patients treated in the Neurosurgical department of 1st Affiliated Hospital of WCUMS, from October 1983 through May 1984. The follow-up results showed that a good correlation was observed between the score of C1CS and the outcome scale score (Glasgow outcome scale, GOS) of the patients.

Relation between Glasgow coma score and cough reflex

How unconscious does a patient need to be, to be intubated without drugs? In 76 comatose patients (Glasgow coma score [GCS] < or = 8) who were treated consecutively in an emergency department, the integrity of the cough reflex was not related to GCS. All comatose patients must be treated as if their airway is compromised but even at the lowest coma scores, there are many patients whose airway reflexes are sufficiently intact to make procedures such as endotracheal intubation difficult and dangerous without drugs. The state of the airway should be assessed independently of conscious level.

[Assessment of the deepness of coma in children. Evolution of clinical thoughts]

Clinical assessment is an essential fundamental element in the evaluation of comatose states, particularly in children. Paediatricians quickly recognized that the early Glasgow Coma Scale, used for over 20 years in adults, is inadapted for children because it lacks brain stem criteria, involves interpretation of motor response (particularly difficult in infants) and uses verbal response which is of little value before language acquisition. The first attempt at standardized coma assessment in children was the Paediatric Coma Scale, developed in Australia in 1982. This scale improved on the Glasgow scale, removing the motor retraction response, modifying the verbal response scale (normal, words, sounds, crying, or none) and quantifying the best possible score as a function of age. In 1983 a fundamental modification was proposed in the Jacob scale. Besides removing the motor retraction response, this scale replaced the verbal scale with one based on ocular behaviour, thus evaluating consciousness of presence or stimulation. The vestibular response and pupil reactions were also included to assess brain stem activity. In 1987, we introduced the Bicêtre scale which uses ocular behaviour instead of verbal response and separates ocular diameter as a specific criteria. Assessment of four reflexes (mimic, photomotor, cornea and cough) provides precise information on the activities of the different levels of the brain stem. Several comparative studies have been conducted to determine the positive predictive value and interpersonal variability of these scales. In a prospective multicentric study of 277 comatose children aged 6 months to 15 years, we found that the Bicêtre scale had a positive predictive value of 94% for good outcome at 24 hours and that interpersonal disagreement occurred in only 10.1% of 65 cases studied (compared with 13.5% for the Glasgow scale which was studied simultaneously). Paediatricians now have reliable clinical scales for assessing the conscious level in children.

[Examination and observation of the unconscious patient]

The old neurological art of careful examination and detailed description of an unconscious patient delivers a vivid picture of cerebral functions and deficiencies. Daily medical practice, however, demands immediate information with measurable and easily comparable numerical values. This requirement is best satisfied by the current proven and universally accepted 'Glasgow Coma Scale'. Dispensing with the terms: somnolent, soporous and comatose, the GCS numerically marks the depth of the disturbances of consciousness, which, recorded in a graph, indicate the fluctuations of consciousness. The registration of the depth and duration of clouded consciousness is a decisive criterion for the prognosis.