Clinical supervisors' experience of a first-time application of entrustable professional activities in clinical supervision of medical students: findings from a Swedish pilot study

BACKGROUND

Recently, all medical universities in Sweden jointly developed a framework for Entrustable Professional Activities (EPAs) for work-based training and assessment. This framework is now being introduced nationally in the new 6-year undergraduate medical programme that directly lead to a licence to practise. When EPAs are introduced, it is of central importance to gain clinical supervisors' acceptance to apply the framework in their supervision of students. The aim of this study was therefore to investigate how clinical supervisors, not familiar with EPAs, experience clinical supervision using the framework for EPAs.

METHODS

We used a purposive sampling to recruit clinical supervisors. They were given written information on EPAs with a selection of suitable EPAs and the Swedish observation rating scale for assessment of autonomy, and they were offered to attend a 30-minute introductory web course. The participants were informed that EPAs were to be tested, and the students were asked to participate. After the study period the clinical supervisors participated in semi-structured interviews. Inductive qualitative content analysis was used to analyse the transcribed interviews.

RESULTS

Three general themes emerged in the qualitative analysis: Promoting Feedback, Trusting Assessments and Engaging Stakeholders. The participants described benefits from using EPAs, but pointed out a need for preparation and adaptation to facilitate implementation. The structure was perceived to provide structured support for feedback, student involvement, entrustment decisions, enabling supervisors to allow the students to do more things independently, although some expressed caution to rely on others' assessments. Another concern was whether assessments of EPAs would be perceived as a form of examination, steeling focus from formative feedback. To understand the concept of EPA, the short web-based course and written information was regarded as sufficient. However, concern was expressed whether EPA could be applied by all clinical supervisors. Involvement and adaption of the workplace was pointed out as important since more frequent observation and feedback, with documentation requirements, increase the time required for supervision.

CONCLUSIONS

EPAs were accepted as beneficial, promoting structured feedback and assessments of the students' autonomy. Preparation of supervisors and students as well as involvement and adaptation of the workplace was pointed out as important.

Physicians' self-perceived preparedness for clinical supervision of medical students at university and non-university hospitals -results from a Swedish survey

BACKGROUND

The need for clinical placements outside traditional teaching hospitals for medical students is growing, both due to a decrease in hospital beds and the expansion of medical students. In this survey, distributed to supervisors at university and non-university hospitals, we investigated supervisors' self-perceived preparedness for the training assignment and searched for factors associated with self-perceived pedagogical knowledge and familiarity with the students' learning objectives.

METHODS

A pilot survey was developed using results from qualitative studies regarding clinical supervision of medical students and included questions on the supervisors' education and preparation, if they were familiar with the students' learning objectives, self-perceived pedagogical knowledge, and characteristics of the learning environment. The pilot survey was tested on a smaller group of supervisors. The results from the pilot survey were used to develop an e-survey that was distributed to all hospital employed physicians in Region Västra Götaland.

RESULTS

The survey was completed by 1732 physicians (response rate 43%). Among 517 respondents at the university hospital who reported activity as supervisor, 240 (46%) had attended preparatory supervisor training, 423 (82%) perceived enough pedagogical knowledge for the teaching assignment, and 391 (76%) reported familiarity with the learning objectives. The corresponding proportions at non-university hospitals were 159/485 (33%), 363/485 (75%), and 298/485 (61%), respectively (p ≤ .007 all through, compared to the university hospital). Perceiving that goal description and written information from the course management was sufficient for being able to complete the training assignment showed strong association with both self-perceived pedagogical knowledge and familiarity with the students' learning objectives.

CONCLUSIONS

We found consistent differences between university and non-university hospitals with respect to the supervisors' self-perceived preparedness for the training assignment. Efforts to convey the learning objectives and support to clinical supervisors are crucial for supervision of students at non-university hospitals.

Care practices for patients requiring mechanical ventilation more than seven days in Swedish intensive care units: A national survey

OBJECTIVE

To identify care practices in Swedish intensive care units specific to patients requiring mechanical ventilation for >7 days.

RESEARCH METHODOLOGY

We conducted a national cross-sectional survey inviting all adult Swedish ICUs (n = 79). Nurse managers were invited by email to complete a questionnaire by telephone. The questionnaire included seven domains: ventilator weaning, mobilisation, communication, nutrition, symptom assessment, psychosocial support and organisational characteristics.

RESULTS

We received responses from 77 units (response rate, 97%). Weaning protocols were available in 42 (55%) units, 52 (68%) used individualised weaning strategies and 50 (65%) involved physicians and nurses in collaborative decision making. In 48 units (62%), early mobilisation was prioritised using bed cycling but only 26 (34%) units had mobilisation protocols. Most of the intensive care units (74, 96%) had nutrition protocols but only 2 (3%) had dedicated dieticians. Delirium screening tools were available in 49 (64%) ICUs, 3 (4%) assessed anxiety and none assessed dyspnoea. Nineteen (25%) units employed a primary nursing model and 11 (14%) indicated person-centred care policies. Regular case conferences, including family participation, were held by 39 (51%) units.

CONCLUSION

We found that an individualised approach to ventilator weaning, decided by physicians and nurses in collaboration, was the predominant approach, although weaning protocols were available in some intensive care units. Most units prioritised early mobilisation, though few used protocols. Nutritional protocols were widely adopted, as few units had a dedicated dietician.

Long-term outcomes after aneurysmal subarachnoid hemorrhage: A prospective observational cohort study

OBJECTIVES

The survival rates for patients affected by aneurysmal subarachnoid hemorrhage (aSAH) have increased in recent years; however, many patients continue to develop cognitive dysfunctions that affect their quality of life. The commonly used outcome measures often fail to identify these cognitive dysfunctions. This study aimed to evaluate the long-term outcomes at 1 and 3 years after aSAH to assess changes over time and relate outcomes to patient characteristics and events during the acute phase.

MATERIALS AND METHODS

This prospective observational study included patients that experienced aSAH. Patients were assessed according to the extended Glasgow Outcome Scale, Life Satisfaction Questionnaire, Mayo-Portland Adaptability inventory-4, and Mental Fatigue scale.

RESULTS

Patients were assessed after 1 year (n = 62) and 3 years (n = 54). At 3 years, the extended Glasgow Outcome Scale score improved in 15% and worsened in 12% of the patients. Mental fatigue was observed in 57% of the patients at 1 year. Patients <60 years of age at the time of aSAH had more self-assessed problems, including pain/headache (p < .01), than patients >60 years of age. Patients with delayed cerebral ischemia during the acute phase reported more dissatisfaction at 3 years, whereas no significant result was seen at 1 year.

CONCLUSIONS

Cognitive dysfunction, especially mental fatigue, is common in patients with aSAH, which affects quality of life and recovery. Patient outcome is a dynamic process developing throughout years after aSAH, involving both improvement and deterioration. This study indicates the importance of longer follow-up periods with broad outcome assessments.

Machine learning analysis of heart rate variability to detect delayed cerebral ischemia in subarachnoid hemorrhage

OBJECTIVES

Approximately 30% of patients with aneurysmal subarachnoid hemorrhage (aSAH) develop delayed cerebral ischemia (DCI). DCI is associated with increased mortality and persistent neurological deficits. This study aimed to analyze heart rate variability (HRV) data from patients with aSAH using machine learning to evaluate whether specific patterns could be found in patients developing DCI.

MATERIAL & METHODS

This is an extended, in-depth analysis of all HRV data from a previous study wherein HRV data were collected prospectively from a cohort of 64 patients with aSAH admitted to Sahlgrenska University Hospital, Gothenburg, Sweden, from 2015 to 2016. The method used for analyzing HRV is based on several data processing steps combined with the random forest supervised machine learning algorithm.

RESULTS

HRV data were available in 55 patients, but since data quality was significantly low in 19 patients, these were excluded. Twelve patients developed DCI. The machine learning process identified 71% of all DCI cases. However, the results also demonstrated a tendency to identify DCI in non-DCI patients, resulting in a specificity of 57%.

CONCLUSIONS

These data suggest that machine learning applied to HRV data might help identify patients with DCI in the future; however, whereas the sensitivity in the present study was acceptable, the specificity was low. Possible confounders such as severity of illness and therapy may have affected the result. Future studies should focus on developing a robust method for detecting DCI using real-time HRV data and explore the limits of this technology in terms of its reliability and accuracy.

Prevalence and Intensive Care Bed Use in Subjects on Prolonged Mechanical Ventilation in Swedish ICUs

BACKGROUND

The number of patients requiring prolonged mechanical ventilation (PMV) is predicted to escalate due to an aging population. International studies on prevalence and resource utilization of this patient group exist, but data are lacking from Scandinavian ICUs, where there is a relatively low number of ICU beds in relation to population. The primary aim was to identify prevalence of admissions requiring mechanical ventilation ≥ 7-21 d and PMV > 21 d, and their use of ICU bed days in Sweden. Secondary aims were to describe patient characteristics and outcomes.

METHODS

We obtained data from the Swedish Intensive Care Registry on admissions age ≥ 18 y mechanically ventilated ≥ 7 d and used open source registry data to calculate the prevalence and use of bed days of admissions ventilated ≥ 7-21 d and PMV > 21 d.

RESULTS

Of the 39,510 ICU admissions to Swedish ICUs in 2017, those mechanically ventilated ≥ 7-21 d accounted for 1,643 (4%) admissions, and those with PMV > 21 d accounted for 307 (0.8%) admissions. Of the 109,457 ICU bed days, 22% were consumed by admissions ventilated ≥ 7-21 d and 10% by those with PMV > 21 d. The ICU mortality of both groups was 21%. Admissions with mechanical ventilation ≥ 7 d had a median age of 65 y and were predominantly male (64%).

CONCLUSIONS

Admissions to Swedish ICUs who required mechanical ventilation ≥ 7-21 d and PMV > 21 d form a relatively small proportion of all ICU admissions, but consume a significant proportion of ICU beds days. Prevalence of admissions, ICU bed days, and ICU mortality were lower than reports from other countries, but the admissions were predominantly elderly and male, in accordance with other reports.

Association between inflammatory response and outcome after subarachnoid haemorrhage

Objectives

Recent reports suggest an association between the inflammatory response after aneurysmal subarachnoid haemorrhage (aSAH) and patients' outcome. The primary aim of this study was to identify a potential association between the inflammatory response after aSAH and 1‐year outcome. The secondary aim was to investigate whether the inflammatory response after aSAH could predict the development of delayed cerebral ischaemia (DCI).

Materials and methods

This prospective observational pilot study included patients with an aSAH admitted to Sahlgrenska University Hospital, Gothenburg, Sweden, between May 2015 and October 2016. The patients were stratified according to the extended Glasgow Outcome Scale (GOSE) as having an unfavourable (score: 1–4) or favourable outcome (score: 5–8). Furthermore, patients were stratified depending on development of DCI or not. Patient data and blood samples were collected and analysed at admission and after 10 days.

Results

Elevated serum concentrations of inflammatory markers such as tumour necrosis factor‐α and interleukin (IL)‐6, IL‐1Ra, C‐reactive protein and intercellular adhesion molecule‐1 were detected in patients with unfavourable outcome. When adjustments for Glasgow coma scale were made, only IL‐1Ra remained significantly associated with poor outcome (p = 0.012). The inflammatory response after aSAH was not predictive of the development of DCI.

Conclusion

Elevated serum concentrations of inflammatory markers were associated with poor neurological outcome 1‐year after aSAH. However, inflammatory markers are affected by many clinical events, and when adjustments were made, only IL‐1Ra remained significantly associated with poor outcome. The robustness of these results needs to be tested in a larger trial.

Cerebral ischemia detection using artificial intelligence (CIDAI)-A study protocol

BACKGROUND

The onset of cerebral ischemia is difficult to predict in patients with altered consciousness using the methods available. We hypothesize that changes in Heart Rate Variability (HRV), Near-Infrared Spectroscopy (NIRS), and Electroencephalography (EEG) correlated with clinical data and processed by artificial intelligence (AI) can indicate the development of imminent cerebral ischemia and reperfusion, respectively. This study aimed to develop a method that enables detection of imminent cerebral ischemia in unconscious patients, noninvasively and with the support of AI.

METHODS

This prospective observational study will include patients undergoing elective surgery for carotid endarterectomy and patients undergoing acute endovascular embolectomy for cerebral arterial embolism. HRV, NIRS, and EEG measurements and clinical information on patient status will be collected and processed using machine learning. The study will take place at Sahlgrenska University Hospital, Gothenburg, Sweden. Inclusion will start in September 2020, and patients will be included until a robust model can be constructed. By analyzing changes in HRV, EEG, and NIRS measurements in conjunction with cerebral ischemia or cerebral reperfusion, it should be possible to train artificial neural networks to detect patterns of impending cerebral ischemia. The analysis will be performed using machine learning with long short-term memory artificial neural networks combined with convolutional layers to identify patterns consistent with cerebral ischemia and reperfusion.

DISCUSSION

Early signs of cerebral ischemia could be detected more rapidly by identifying patterns in integrated, continuously collected physiological data processed by AI. Clinicians could then be alerted, and appropriate actions could be taken to improve patient outcomes.

Heart rate variability monitoring for the detection of delayed cerebral ischemia after aneurysmal subarachnoid hemorrhage

BACKGROUND

Delayed cerebral ischemia (DCI) is a major cause of impaired outcome after aneurysmal subarachnoidal hemorrhage (aSAH). In this observational cohort study we investigated whether changes in heart rate variability (HRV) that precede DCI could be detected.

METHODS

Sixty-four patients with aSAH were included. HRV data were collected for up to 10 days and analyzed offline. Correlation with clinical status and/or radiologic findings was investigated. A linear mixed model was used for the evaluation of HRV parameters over time in patients with and without DCI. Extended Glasgow outcome scale score was assessed after 1 year.

RESULTS

In 55 patients HRV data could be analyzed. Fifteen patients developed DCI. No changes in HRV parameters were observed 24 hours before onset of DCI. Mean of the HRV parameters in the first 48 hours did not correlate with the development of DCI. Low/high frequency (LF/HF) ratio increased more in patients developing DCI (β -0.07 (95% confidence interval, 0.12-0.01); P = .012). Lower STDRR (standard deviation of RR intervals), RMSSD (root mean square of the successive differences between adjacent RR intervals), and total power (P = .003, P = .007 and P = .004 respectively) in the first 48 hours were seen in patients who died within 1 year.

CONCLUSION

Impaired HRV correlated with 1-year mortality and LF/HF ratio increased more in patients developing DCI. Even though DCI could not be detected by the intermittent analysis of HRV used in this study, continuous HRV monitoring may have potential in the detection of DCI after aSAH using different methods of analysis.

Swedish intensivists' experiences and attitudes regarding end-of-life decisions

BACKGROUND

To make end-of-life (EOL) decisions is a complex and challenging task for intensive care physicians and a substantial variability in this process has been previously reported. However, a deeper understanding of intensivists' experiences and attitudes regarding the decision-making process is still, to a large extent, lacking. The primary aim of this study was to address Swedish intensivists' experiences, beliefs and attitudes regarding decision-making pertaining to EOL decisions. Second, we aimed to identify underlying factors that may contribute to variability in the decision-making process.

METHOD

This is a descriptive, qualitative study. Semi-structured interviews with nineteen intensivists from five different Swedish hospitals, with different ICU levels, were performed from 1 February 2017 to 31 May 2017.

RESULTS

Intensivists strive to make end-of-life decisions that are well-grounded, based on sufficient information. Consensus with the patient, family and other physicians is important. Concurrently, decisions that are made with scarce information or uncertain medical prognosis, decisions made during on-call hours and without support from senior consultants cause concern for many intensivists. Underlying factors that contribute to the variability in decision-making are lack of continuity among senior intensivists, lack of needed support during on-call hours and disagreements with physicians from other specialties. There is also an individual variability primarily depending on the intensivist's personality.

CONCLUSION

Swedish intensivists' wish to make end-of-life decisions based on sufficient information, medically certain prognosis and consensus with the patient, family, staff and other physicians. Swedish intensivists' experience a variability in end-of-life decisions, which is generally accepted and not questioned.

Age, SAPS 3 and female sex are associated with decisions to withdraw or withhold intensive care

BACKGROUND

Intensive care treat critically ill patients. When intensive care is not considered beneficial for the patient, decisions to withdraw or withhold treatments are made. We aimed to identify independent patient variables that increase the odds for receiving a decision to withdraw or withhold intensive care.

METHODS

Registry study using data from the Swedish Intensive Care Registry (SIR) 2014-2016. Age, condition at admission, including co-morbidities (Simplified Acute Physiology Score version 3, SAPS 3), diagnosis, sex, and decisions on treatment limitations were extracted. Patient data were divided into a full care (FC) group, and a withhold or withdraw (WW) treatment group.

RESULTS

Of all 97 095 cases, 47.1% were 61-80 years old, 41.9% were women and 58.1% men. 14 996 (15.4%) were allocated to the WW group and 82 149 (84.6%) to the FC group. The WW group, compared with the FC group, was older (P < 0.001), had higher SAPS 3 (P < 0.001) and were predominantly female (P < 0.001). Compared to patients 16-20 years old, patients >81 years old had 11 times higher odds of being allocated to the WW group. Higher SAPS 3 (continuous) increased the odds of being allocated to the WW group by odds ratio [OR] 1.085, (CI 1.084-1.087). Female sex increased the odds of being allocated to the WW group by 18% (1.18; CI 1.13- 1.23).

CONCLUSION

Older age, higher SAPS 3 at admission and female sex were found to be independent variables that increased the odds to receive a decision to withdraw or withhold intensive care.

Mental fatigue assessment may add information after aneurysmal subarachnoid hemorrhage

BACKGROUND

Mental fatigue, as part of cognitive dysfunction, has been reported to be common after subarachnoid hemorrhage and it significantly affects quality of life.

AIMS OF THE STUDY

The aim of this study was to assess mental fatigue one year after an aneurysmal subarachnoid hemorrhage and to correlate the degree of mental fatigue to functional outcome assessed with the Extended Glasgow Outcome Scale (GOSE).

METHODS

One year after an aneurysmal subarachnoid hemorrhage, the GOSE was assessed and a questionnaire for self-assessment of mental fatigue, the Mental Fatigue Scale, was distributed to all included patients. The maximum score is 42 and a score of ≥10.5 indicates mental fatigue.

RESULTS

All patients with GOSE 8, indicating full recovery, had a mental fatigue score of <10.5. A linear correlation between the GOSE and the mental fatigue score was observed (p < 0.0001).

CONCLUSIONS

Patients with a favorable outcome and GOSE 5-7 could benefit from the assessments of mental fatigue in order to receive satisfactory rehabilitation.

Speckle tracking-vs conventional echocardiography for the detection of myocardial injury-A study on patients with subarachnoid haemorrhage

BACKGROUND

Myocardial injury with regional wall motion abnormalities (RWMA) is common in subarachnoid haemorrhage (SAH). We hypothesized that the diagnostic performance of left ventricular (LV) global and regional longitudinal strain (GLS and RLS, respectively), assessed with speckle tracking echocardiography is superior to standard echocardiography for the detection of myocardial injury in SAH.

METHODS

Seventy-one unselected patients with verified SAH were included. Echocardiography was performed within 48 hours after admission. hsTnT was followed daily up to 3 days post-admission. RWMA, LV ejection fraction (LVEF), GLS and RLS were analysed by two experienced echocardiographists, blinded to the information on plasma hsTnT. A reduced GLS was defined as >-15%. Two cut-off levels were used for the definition of RLS, ie when segmental strain was >-15% (liberal) or >-11% (conservative) in ≥2 adjacent segments. Myocardial injury was defined as a peak hsTnT ≥90 ng/L.

RESULTS

The incidence of myocardial injury was 25%. The hsTnT (median, 25% and 75% percentile) in patients with (a) reduced LV ejection fraction (LVEF <50%, n = 10) was 502 (175-718), (b) RWMA (n = 12) was 648 (337-750), (c) reduced GLS (n = 12) was 502 (132-750) and (d) reduced RLS (n = 42) was 40 (10-216), respectively. The specificity/sensitivity for LVEF, RWMA, GLS and RLS to detect myocardial injury 98%/50%, 100%/67%, 96%/56% and 54%/94%, respectively. The intra- and inter-observer variability for assessment of RLS was high.

CONCLUSION

The diagnostic performance of GLS by strain imaging is not superior to standard echocardiography for the detection of myocardial injury in SAH. RLS could not reliably detect regional myocardial injury.

Person-centred care during prolonged weaning from mechanical ventilation, nurses' views: an interview study

OBJECTIVE

To determine: 1) if the three elements of person-centred care (initiating, working and safeguarding the partnership) were present, and 2) to identify evidence of barriers to person-centred care during prolonged weaning from mechanical ventilation.

RESEARCH METHODOLOGY

Secondary analysis of semi structured interviews with 19 critical care nurses using theoretical thematic analysis.

SETTING

This study was conducted in three Swedish intensive care units, one in a regional hospital and two in a university hospital.

FINDINGS

Three themes and nine subthemes related to person-centred care were identified. The three themes included: 1) 'finding a person behind the patient' related to the 'initiating the partnership' phase, 2) 'striving to restore patient́s sense of control' related to 'working the partnership' phase and 3) 'impact of patient involvement' related to 'safeguarding the partnership' phase of person-centred care'. Additionally a further theme 'barriers to person-centred care' was identified.

CONCLUSION

We found evidence of all three person-centred care routines. Barriers to person-centred care comprised of lack team collaboration and resources. Facilitating patients to actively participate in decision-making during the weaning process may optimise weaning outcomes and warrants further research.

Leptin levels after subarachnoid haemorrhage are gender dependent

Background

Subarachnoid hemorrhage (SAH) is a neurological disease where the majority of the patients are critically ill. The adipokine leptin has in cerebral emergencies been related to severity of disease and to adverse outcome. The aim of this study was to examine leptin levels over time after SAH and associations to gender, age, body mass index, severity of disease, parenteral lipids, systemic organ failure and outcome.

Methods

Prospective observational study in 56 patients. Leptin was obtained 0–240 h after SAH, in 48 h intervals. Severity of disease was assessed with the Hunt and Hess score, organ failure with the sequential organ failure assessment score, and outcome with Glasgow outcome scale. Leptin levels in the SAH group were compared with controls from the same geographical area.

Results

At admission, Leptin was significantly higher in SAH patients compared to controls, both in female (28.6 ± 25.6 vs 13.0 ± 2.3 ng/mL, p = 0.001) and male patients (13.3 ± 8.4 vs 4.3 ± 0.7 ng/mL, p = 0.001). Leptin levels remained stable over time. Female patients had significantly higher leptin levels than male patients, and deceased female patients had higher leptin levels than female survivors (85.5 ± 20.5 vs 50.5 ± 34.6, n = 4/35, p < 0.05). Leptin levels did not differ between male survivors and non-survivors. Leptin levels were not associated with severity of disease, organ failure or parenteral lipids.

Conclusion

Leptin levels were significantly higher in both male and female patients compared to controls. Higher leptin levels were related to outcome and organ failure in women but not in men. When analysing leptin levels gender-related differences should be considered.

Long-term subarachnoid haemorrhage survivors still die due to cerebrovascular causes

OBJECTIVE

Subarachnoid haemorrhage (SAH) is associated with sympathetic nervous activation and inflammation. SAH could therefore theoretically be a risk factor for development of cardiovascular disease. The aim of this study was to investigate whether long-term (≥1 year) SAH survivors had an increased risk of death due to cardiovascular causes.

MATERIAL & METHODS

SAH patients ≥18 years treated at Umeå University Hospital between 1986 and 2006 were eligible for inclusion. Deceased patients were identified in the Swedish population register. Death certificates from long-term SAH survivors and causes of death in the general population were obtained from the National Board of Health and Welfare, Sweden. The prevalence of comorbidities at the time of SAH was compared with the distribution of cardiovascular risk factors in the northern Sweden MONICA (Multinational Monitoring of Trends and Determinants in Cardiovascular Disease) health survey. Analyses were stratified for age and sex.

RESULTS

In the SAH patients, the median year of SAH was 1992 and the median year of death was 2001. The MONICA survey in 1994 and the distribution of deaths in the general population in 2001 were used for comparison. Long-term SAH survivors had, compared to the general population, a significantly increased risk for death due to cerebrovascular disease (P < 0.0001), but not for death due to cardiovascular disease. Hypertension was more common in SAH patients compared to survey participants (P < 0.01).

CONCLUSION

Cerebrovascular causes of death were significantly more common in long-term survivors after SAH compared to the general population.

Saliva stimulation with glycerine and citric acid does not affect salivary cortisol levels

OBJECTIVE

In critically ill patients with hypotension, who respond poorly to fluids and vasoactive drugs, cortisol insufficiency may be suspected. In serum over 90% of cortisol is protein-bound, thus routine measures of total serum cortisol may yield 'false lows' due to hypoproteinaemia. Thus, the occurrence of cortisol insufficiency could be overestimated in critically ill patients. Salivary cortisol can be used as a surrogate for free serum cortisol, but in critically ill patients saliva production is decreased, and insufficient volume of saliva for analysis is a common problem. The aim of this study was to investigate if a cotton-tipped applicator with glycerine and citric acid could be used for saliva stimulation without affecting salivary cortisol levels.

DESIGN

Prospective, observational study.

PARTICIPANTS

Thirty-six volunteers (six males, 30 females), age 49 ± 9 years, without known oral mucus membrane rupture in the mouth.

MEASUREMENTS

Forty-two pairs of saliva samples (22 paired morning samples, 20 paired evening samples) were obtained before and after saliva stimulation with glycerine and citric acid. Salivary cortisol was analysed using Spectria Cortisol RIA (Orion Diagnostica, Finland).

RESULTS

The paired samples correlated significantly (P < 0.0001) and there was no significant difference between un-stimulated and stimulated salivary cortisol levels.

CONCLUSIONS

Saliva stimulation with a cotton-tipped applicator containing glycerine and citric acid did not significantly influence salivary cortisol levels in healthy volunteers. This indicates that salivary cortisol measurement after saliva stimulation may be a useful complement when evaluating cortisol status in critically ill patients.

Adrenal response after trauma is affected by time after trauma and sedative/analgesic drugs

BACKGROUND

The adrenal response in critically ill patients, including trauma victims, has been debated over the last decade. The aim of this study was to assess the early adrenal response after trauma.

METHODS

Prospective, observational study of 50 trauma patients admitted to a level-1-trauma centre. Serum and saliva cortisol were followed from the accident site up to five days after trauma. Corticosteroid binding globulin (CBG), dehydroepiandrosterone (DHEA) and sulphated dehydroepiandrosterone (DHEAS) were obtained twice during the first five days after trauma. The effect of time and associations between cortisol levels and; severity of trauma, infusion of sedative/analgesic drugs, cardiovascular dysfunction and other adrenocorticotropic hormone (ACTH) dependent hormones (DHEA/DHEAS) were studied.

RESULTS

There was a significant decrease over time in serum cortisol both during the initial 24 h, and from the 2nd to the 5th morning after trauma. A significant decrease over time was also observed in calculated free cortisol, DHEA, and DHEAS. No significant association was found between an injury severity score ≥ 16 (severe injury) and a low (< 200 nmol/L) serum cortisol at any time during the study period. The odds for a serum cortisol < 200 nmol/L was eight times higher in patients with continuous infusion of sedative/analgesic drugs compared to patients with no continuous infusion of sedative/analgesic drugs.

CONCLUSION

Total serum cortisol, calculated free cortisol, DHEA and DHEAS decreased significantly over time after trauma. Continuous infusion of sedative/analgesic drugs was independently associated with serum cortisol < 200 nmol/L.

Effects of prostacyclin on the early inflammatory response in patients with traumatic brain injury-a randomised clinical study

OBJECTIVE AND DESIGN

A prospective, randomised, double-blinded, clinical trial was performed at a level 1 trauma centre to determine if a prostacyclin analogue, epoprostenol (Flolan®), could attenuate systemic inflammatory response in patients with severe traumatic brain injury (TBI).

SUBJECTS

46 patients with severe TBI, randomised to epoprostenol (n = 23) or placebo (n = 23).

TREATMENT

Epoprostenol, 0.5 ng · kg(-1) · min(-1), or placebo (saline) was given intravenously for 72 hours and then tapered off over the next 24 hours.

METHODS

Interleukin-6 (IL-6), interleukin-8 (IL-8), soluble intracellular adhesion molecule-1 (sICAM-1), C-reactive protein (CRP), and asymmetric dimethylarginine (ADMA) levels were measured over five days. Measurements were made at 24 h intervals ≤24 h after TBI to 97-120 h after TBI.

RESULTS

A significantly lower CRP level was detected in the epoprostenol group compared to the placebo group within 73-96 h (p = 0.04) and within 97-120 h (p = 0.008) after trauma. IL-6 within 73-96 h after TBI was significantly lower in the epoprostenol group compared to the placebo group (p = 0.04). ADMA was significantly increased within 49-72 h and remained elevated, but there was no effect of epoprostenol on ADMA levels. No significant differences between the epoprostenol and placebo groups were detected for IL-8 or sICAM-1.

CONCLUSIONS

Administration of the prostacyclin analogue epoprostenol significantly decreased CRP and, to some extent, IL-6 levels in patients with severe TBI compared to placebo. These findings indicate an interesting option for treatment of TBI and warrants future larger studies.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier, NCT01363583.

Frequency of non-convulsive seizures and non-convulsive status epilepticus in subarachnoid hemorrhage patients in need of controlled ventilation and sedation

BACKGROUND

Non-convulsive seizures (NCSZ) can be more prevalent than previously recognized among comatose neuro-intensive care patients. The aim of this study was to evaluate the frequency of NCSZ and non-convulsive status epilepticus (NCSE) in sedated and ventilated subarachnoid hemorrhage (SAH) patients.

METHODS

Retrospective study at a university hospital neuro-intensive care unit, from January 2008 until June 2010. Patients were treated according to a local protocol, and were initially sedated with midazolam or propofol or combinations of these sedative agents. Thiopental was added for treatment of intracranial hypertension. No wake-up tests were performed. Using NicoletOne(®) equipment (VIASYS Healthcare Inc., USA), continuous EEG recordings based on four electrodes and a reference electrode was inspected at full length both in a two electrode bipolar and a four-channel referential montage.

RESULTS

Approximately 5,500 h of continuous EEG were registered in 28 SAH patients (33 % of the patients eligible for inclusion). The median Glasgow Coma scale was 8 (range 3-14) and the median Hunt and Hess score was 4 (range 1-4). During EEG registration, no clinical seizures were observed. In none of the patients inter ictal epileptiform activity was seen. EEG seizures were recorded only in 2/28 (7 %) patients. One of the patients experienced 4 min of an NCSZ and one had a 5 h episode of an NCSE.

CONCLUSION

Continuous EEG monitoring is important in detecting NCSZ in sedated patients. Continuous sedation, without wake-up tests, was associated with a low frequency of subclinical seizures in SAH patients in need of controlled ventilation.

Severe traumatic brain injury: consequences of early adverse events

BACKGROUND

Several factors associated with an unfavourable outcome after severe traumatic brain injury (TBI) have been described: prolonged pre-hospital time, secondary referral to a level 1 trauma centre, the occurrence of secondary insults such as hypoxia, hypotension or low end-tidal carbon dioxide (ETCO(2)). To determine whether adverse events were linked to outcome, patients with severe TBI were studied before arrival at a level 1 trauma centre.

METHODS

Prospective, observational study design. Patients with severe TBI (n = 48), admitted to Umeå University Hospital between January 2002 to December 2005 were included. All medical records from the site of the accident to arrival at the level 1 trauma centre were collected and evaluated.

RESULTS

A pre-hospital time of >60 min, secondary referral to a level 1 trauma centre, documented hypoxia (oxygen saturation <95%), hypotension (systolic blood pressure <90 mmHg), hyperventilation (ETCO(2) <4.5 kPa) or tachycardia (heart rate >100 beats/min) at any time before arrival at a level 1 trauma centre were not significantly related to an unfavourable outcome (Glasgow Outcome Scale 1-3).

CONCLUSION

Early adverse events before arrival at a level 1 trauma centre were without significance for outcome after severe TBI in the trauma system studied.

Prostacyclin treatment in severe traumatic brain injury: a microdialysis and outcome study

Prostacyclin (PGI(2)) is a potent vasodilator, inhibitor of leukocyte adhesion, and platelet aggregation. In trauma the balance between PGI(2) and thromboxane A(2) (TXA(2)) is shifted towards TXA(2). Externally provided PGI(2) would, from a theoretical and experimental point of view, improve the microcirculation in injured brain tissue. This study is a prospective consecutive double-blinded randomized study on the effect of PGI(2) versus placebo in severe traumatic brain injury (sTBI). All patients with sTBI were eligible.

INCLUSION CRITERIA

verified sTBI, Glasgow Coma Score (GCS) at intubation and sedation of <or=8, age 15-70 years, a first-recorded cerebral perfusion pressure (CPP) of >or=10 mm Hg, and arrival within 24 h of trauma. All subjects received an intracranial pressure (ICP) measuring device, bilateral intracerebral microdialysis catheters, and a microdialysis catheter in the abdominal subcutaneous adipose tissue. Subjects were treated according to an ICP-targeted therapy based on the Lund concept. 48 patients (mean age of 35.5 years and a median GCS of 6 [3-8]) were included. We found no significant effect of prostacyclin (epoprostenol, Flolan) on either the lactate-pyruvate ratio (L/P) at 24 h or the brain glucose levels. There was no significant difference in clinical outcome between the two groups. The median Glasgow Outcome Score (GOS) at 3 months was 4, and mortality was 12.5%. The favorable outcome (GOS 4-5) was 52%. The initial L/P did not prognosticate for outcome. Thus our results indicate that there is no effect of PGI(2) at a dose of 0.5 ng/kg/min on brain L/P, brain glucose levels, or outcome at 3 months.

Non-traumatic subarachnoid hemorrhage is associated with subnormal blood creatinine levels

OBJECTIVE

The aim of this study was to examine the hypothesis that patients with non-traumatic subarachnoid hemorrhage (SAH) have statistically significant subnormal creatinine levels and that the creatinine levels are associated with severity of disease.

MATERIALS AND METHODS

This was a retrospective observational study over 2 years (2005-2006) in which the SAH patients were divided into patients with severe symptoms and patients with mild/moderate symptoms, and were compared to patients with; traumatic brain injury, trauma without brain injury and patients undergoing elective knee surgery. Blood creatinine levels (day 1-3, and day 7) were recorded.

RESULTS

Compared to a normal distribution, SAH patients had statistically significant subnormal creatinine levels day one through seven. SAH patients with severe symptoms had statistically significant subnormal creatinine levels already on day one, in contrast to patients with mild/moderate symptoms. Women with severe symptoms had statistically significant subnormal creatinine levels throughout the study period in contrast to men with severe symptoms who had a normal distribution of creatinine at admission. Women with mild/moderate symptoms had a normal distribution of creatinine only at admission in contrast to men who had a normal distribution of creatinine throughout the study period. Male patients with traumatic brain injury, all trauma patients without brain injury and all patients undergoing elective knee surgery had a normal distribution of creatinine on all studied days.

CONCLUSIONS

SAH is associated with subnormal serum creatinine levels. This finding is more pronounced in patients with severe symptoms and in women.

S-100B and neuron specific enolase are poor outcome predictors in severe traumatic brain injury treated by an intracranial pressure targeted therapy

OBJECTIVE

To prospectively study S-100B and neuron specific enolase (NSE) levels in subjects treated for severe head injury (sTBI), and investigate the prognostic value of these biomarkers.

METHODS

Subjects included in a prospective double blind randomised study for sTBI.

INCLUSION CRITERIA

Glasgow Coma Score (GCS) <or=8, age 15-70 years, first recorded cerebral perfusion pressure of >10 mm Hg and arrival <24 h after trauma. Subjects were treated with an intracranial pressure (ICP) targeted therapy. Blood samples for S-100B and NSE were drawn immediately after arrival and every 12 h for 5 days. Outcome was evaluated as Glasgow Outcome Scale (GOS) by independent staff at 3 and 12 months.

RESULTS

48 subjects, mean age 35.5 years, and median GCS 6 were included. The first blood sample was drawn at 15.6 (1.4) h after injury. Initial concentration of S-100B was 1.04 (0.21) microg/l and for NSE 18.94 (2.32) microg/l. The biomarkers were significantly higher in subjects with GCS 3 and in those who died compared with those with GCS 4-8 and GOS 2-5, respectively. Receiver operated characteristic curve analyses of the initial S-100B and NSE levels to GOS dichotomised as unfavourable (GOS 1-3) and favourable (GOS 4-5) showed a weak correlation: AUC 0.585 and 0.555, respectively. Using the dichotomisation dead (GOS 1)/alive (GOS 2-5), the AUC values were 0.687 and 0.734, respectively. Furthermore, a correlation was found between the biomarkers themselves and the biomarkers and ICP.

CONCLUSION

At 3 and 12 months after trauma, no differences in prognostic values between the markers were apparent nor was there any clinical significant value of the markers as predictors of clinical outcome.

Prostacyclin treatment normalises the MCA flow velocity in nimodipine-resistant cerebral vasospasm after aneurysmal subarachnoid haemorrhage: a pilot study

BACKGROUND

Cerebral vasospasm triggered by subarachnoid haemorrhage is one of the major causes of post-haemorrhage morbidity and mortality. Several treatment modalities have been proposed, and none of them are fully effective.

METHODS

In this study we treated five patients with prostacyclin suffering vasospasm after a ruptured aneurysm not responding to high i.v. doses of nimodipine. All patients were severely ill, unconscious and in need of intensive care.

FINDINGS

A low dose of prostacyclin i.v. infusion for 72 h reversed the vasospasm as measured by transcranial Doppler technique. The mean MCA blood flow velocity decreased from 199 +/- 31 cm/s to 92 +/- 6 cm/s within 72 h after the start of the prostacyclin infusion.

CONCLUSIONS

We suggest that low-dose prostacyclin treatment, an old treatment strategy, can be a treatment option in patients with vasospasm not responding to ordinary measures.

Absence of electroencephalographic seizure activity in patients treated for head injury with an intracranial pressure-targeted therapy

OBJECT

The authors prospectively studied the occurrence of clinical and nonclinical electroencephalographically verified seizures during treatment with an intracranial pressure (ICP)-targeted protocol in patients with traumatic brain injury (TBI).

METHODS

All patients treated for TBI at the Department of Neurosurgery, University Hospital Umeå, Sweden, were eligible for the study. The inclusion was consecutive and based on the availability of the electroencephalographic (EEG) monitoring equipment. Patients were included irrespective of pupil size, pupil reaction, or level of consciousness as long as their first measured cerebral perfusion pressure was > 10 mm Hg. The patients were treated in a protocol-guided manner with an ICP-targeted treatment based on the Lund concept. The patients were continuously sedated with midazolam, fentanyl, propofol, or thiopental, or combinations thereof. Five-lead continuous EEG monitoring was performed with the electrodes at F3, F4, P3, P4, and a midline reference. Sensitivity was set at 100 muV per cm and filter settings 0.5-70 Hz. Amplitude-integrated EEG recording and relative band power trends were displayed. The trends were analyzed offline by trained clinical neurophysiologists.

RESULTS

Forty-seven patients (mean age 40 years) were studied. Their median Glasgow Coma Scale score at the time of sedation and intubation was 6 (range 3-15). In 8.5% of the patients clinical seizures were observed before sedation and intubation. Continuous EEG monitoring was performed for a total of 7334 hours. During this time neither EEG nor clinical seizures were observed.

CONCLUSIONS

Our protocol-guided ICP targeted treatment seems to protect patients with severe TBI from clinical and subclinical seizures and thus reduces the risk of secondary brain injury.

Fluid therapy and the use of albumin in the treatment of severe traumatic brain injury

BACKGROUND

Evidence-based guidelines for severe traumatic brain injury (TBI) do not include strategies for fluid administration. The protocol used in this study includes albumin administration to maintain normal colloid osmotic pressure and advocates a neutral to slightly negative fluid balance. The aim of this study was to analyze the occurrence of organ failure and the mortality in patients with severe TBI treated by a protocol that includes defined strategies for fluid therapy.

METHODS

Ninety-three patients with severe TBI and Glasgow Coma Score <or=8 were included during 1998-2001. Medical records of the first 10 days were retrieved. Organ dysfunction was evaluated with the Sequential Organ Failure Assessment (SOFA) score. Mortality was assessed after 10 and 28 days, 6 and 18 months.

RESULTS

The total fluid balance was positive on days 1-3, and negative on days 4-10. The crystalloid balance was negative from day 2. The mean serum albumin was 38+/-6 g/l. Colloids constituted 40-60% of the total fluids given per day. Furosemide was administered to 94% of all patients. Severe organ failure defined as SOFA >or=3 was evident only for respiratory failure, which was observed in 29%. None developed renal failure. After 28 days, mortality was 11% and, after 18 months, it was 14%.

CONCLUSIONS

A protocol including albumin administration in combination with a neutral to a slightly negative fluid balance was associated with low mortality in patients with severe TBI in spite of a relatively high frequency (29%) of respiratory failure, assessed with the SOFA score.

Effective ICP Reduction by Decompressive Craniectomy in Patients with Severe Traumatic Brain Injury Treated by an ICP-Targeted Therapy

Severe traumatic brain injury (TBI) is one of the major causes of death in younger age groups. In Umeå, Sweden, an intracranial pressure (ICP) targeted therapy protocol, the Lund concept, has been used in treatment of severe TBI since 1994. Decompressive craniectomy is used as a protocol-guided treatment step. The primary aim of the investigation was to study the effect of craniectomy on ICP changes over time in patients with severe TBI treated by an ICP-targeted protocol. In this retrospective study, all patients treated for severe TBI during 1998-2001 who fulfilled the following inclusion criteria were studied: GCS <or= 8 at intubation and sedation, first recorded cerebral perfusion pressure (CPP) of >10 mm Hg, arrival within 24 h of trauma, and need of intensive care for >72 h. Craniectomy was performed when the ICP could not be controlled by evacuation of hematomas, sedation, ventriculostomy, or low-dose pentothal infusion. Ninety-three patients met the inclusion criteria. Mean age was 37.6 years. Twenty-one patients underwent craniectomy as a treatment step. We found a significant reduction of the ICP directly after craniectomy, from 36.4 mm Hg (range, 18-80 mm Hg) to 12.6 mm Hg (range, 2-51 mm Hg). During the following 72 h, we observed an increase in ICP during the first 8-12 h after craniectomy, reaching approximately 20 mm Hg, and later levelling out at approximately 25 mm Hg. The reduction of ICP was statistically significant during the 72 h. The outcome as measured by Glasgow Outcome Scale (GOS) did not significantly differ between the craniectomized group (DC) and the non-craniectomized group (NDC). The outcome was favorable (GOS 5-4) in 71% in the craniectomized group, and in 61% in the non-craniectomized group. Craniectomy is a useful tool in achieving a significant reduction of ICP overtime in TBI patients with progressive intracranial hypertension refractory to medical therapy. The procedure seems to have a satisfactory effect on the outcome, as demonstrated by a high rate of favorable outcome and low mortality in the craniectomized group, which did not significantly differ compared with the non-craniectomized group.

Sympathetic activation and inflammatory response in patients with subarachnoid haemorrhage

OBJECTIVE

The aim of this study was to evaluate the correlation between sympathetic nervous activation and the immune response in patients following subarachnoid haemorrhage (SAH).

DESIGN AND SETTING

Clinical study in a neurosurgical intensive care unit.

PATIENTS AND PARTICIPANTS

Fourteen patients with acute non-traumatic SAH were included. Fifteen healthy, age-matched volunteers served as controls for measurement of catecholamine spillover.

INTERVENTION

Blood sampling for C3a, C5b-9, IL-6, IL-8 and norepinephrine kinetic determination was made within 48 h, at 72 h and on the 7th-10th day after the SAH.

MEASUREMENTS AND RESULTS

SAH patients exhibited a profound increase in the rate of norepinephrine spillover to plasma at 48 h, 72 h and 7-10 days after the insult, 3-4 times that in healthy individuals. The plasma levels of C3a, IL-6 and C5b-9 were significantly elevated at 48 h, at 72 h and 7-10 days after the SAH, but the plasma level of IL-6 decreased significantly 7-10 days after the SAH. There was no relationship between the magnitude of sympathetic activation and the levels of inflammatory markers.

CONCLUSIONS

Following SAH a pronounced activation of the sympathetic nervous system and the inflammatory system occurs. The lack of significant association between the rate of spillover of norepinephrine to plasma and the plasma levels of inflammatory markers indicates that the two processes, sympathetic activation and the immune response, following SAH are not quantitatively linked. In spite of a persistent high level of sympathetic activation the plasma level of IL-6 decreased significantly one week after SAH.

The Swedish Malignant Middle cerebral artery Infarction Study: long-term results from a prospective study of hemicraniectomy combined with standardized neurointensive care

OBJECTIVES

Hemicraniectomy in patients with malignant middle cerebral artery (mMCA) infarct may be life-saving. The long-term prognosis is unknown.

METHODS

Patients with mMCA infarct treated with hemicraniectomy between 1998 and 2002 at three hospitals were included. The criterion for surgical intervention was if the patients deteriorated from awake to being responding to painful stimuli only. All patients were followed for at least 1 year. Outcome was defined as alive/dead, walkers/non-walkers or modified Rankin Scale (mRS) score <or=2.

RESULTS

Thirty patients were included (median age at stroke onset 49 years, range 17-67 years). Fourteen patients had mMCA infarct on the left side and 16 patients on the right side. Fourteen patients had pupil dilatation before surgery. Hemicraniectomy was performed at a median of 52 h (range 13-235 h) after stroke onset. Nine patients died within 1 month after surgery because of cerebral herniation (n = 6), myocardial infarction (n = 1) or intensive care complications (n = 2). No further deaths occurred during follow-up, which was at median 3.4 years after surgery. Status for the 21 survivors at the last follow-up was: mRS 2 or less (n = 6) and mRS 3-5 (n = 15). The oldest patient with mRS 2 or less was 53 years at stroke onset. Thirteen patients (43%) could walk without substantial aid.

CONCLUSION

The long-term survival after mMCA infarction treated with hemicraniectomy seems to be favourable if the patient survives the acute phase. The outcome as measured with mRS may be better among younger patients.

Severe traumatic brain injury in pediatric patients: treatment and outcome using an intracranial pressure targeted therapy—the Lund concept

OBJECTIVE

This study evaluated the outcome of treatment according to the Lund concept in children with severe traumatic brain injury and investigated whether the preset goals of the protocol were achieved.

DESIGN AND SETTING

A two-center retrospective study in neurointensive care units at university hospitals.

PATIENTS

Forty-one children with severe traumatic brain injury from blunt trauma and arriving at hospital within 24 h after injury. Median age was 8.8 years (range 3 months-14.2 years), Glasgow Coma Scale 7 (3-8), and Injury Severity Score 25 (16-75). All children had pathological findings on initial computed tomography. All developed intracranial hypertension, and survivors required intensive care longer than 72 h.

INTERVENTIONS

Treatment according to the principles of the Lund concept.

MEASUREMENTS AND RESULTS

Neurosurgery was required in 46% of the children. Survival rate was 93% and favorable outcome (Glasgow Outcome Score 4 or 5) was 80% at long-term follow-up (median 12 months postinjury, range 2.5-26). The preset physiological and biochemical goals were achieved in over 90% of observations.

CONCLUSIONS

Treating pediatric patients with severe traumatic brain injury, according to the Lund concept, results in a favorable outcome when the protocol is followed.

Reducing intracranial pressure may increase survival among patients with bacterial meningitis

We reported findings concerning continuous intracranial pressure (ICP) and cerebral perfusion pressure (CPP) measurements and mortality in patients with severe bacterial meningitis treated on the basis of an ICP-targeted approach. Eighteen patients with severe bacterial meningitis were admitted for neurointensive care at Umeå University Hospital (Umeå, Sweden). In 15 patients, ICP was measured continuously through an ICP measuring device. During care, all patients but one developed intracranial hypertension with an ICP of >or=15 mm Hg (14 [93%] of 15 patients). Ten (67%) of 15 patients survived and were discharged, and 5 patients (33%) died. Mean ICP was significantly higher and CPP was markedly decreased in nonsurvivors, compared with survivors. Among the survivors, ICP was gradually reduced. Treatment of patients with severe bacterial meningitis should include neurointensive care and continuous ICP measurement. Increased ICP may be reduced by using the ICP-targeted therapy that closely resembles the "Lund concept."

Monoamine metabolism and sympathetic nervous activation following subarachnoid haemorrhage: influence of gender and hydrocephalus

Subarachnoid haemorrhage is a serious condition, often accompanied by cerebral vasospasm and hydrocephalus, which may result in delayed cerebral ischaemia and neurological deterioration. While the mechanisms responsible remain unknown, activation of the sympathetic nervous system, leading to elevated levels of circulating catecholamines is, at least in part, implicated. In this study, we sought to examine the importance of sympathetic nervous activation and its relation to brain monoaminergic neurotransmission in 25 patients following subarachnoid haemorrhage by examining plasma and cerebrospinal fluid levels of the catecholamines noradrenaline, adrenaline and dopamine, and their metabolites. Total body sympathetic activity was concurrently assessed using isotope dilution methodology. In the early phase following subarachnoid haemorrhage patients exhibited markedly elevated rates of spillover of noradrenaline to plasma (9.11 +/- 1.12 vs. 3.39 +/- 0.26 nmol/min, p < 0.01), with rates being higher in those patients in whom hydrocephalus developed (11.15 +/- 1.40 vs. 7.90 +/- 1.41 nmol/min, p = 0.05). The degree of sympathetic nervous activation tended to be higher in females compared with males. Lower cerebral perfusion pressures were observed in those patients in whom cerebrospinal fluid concentrations of noradrenaline and dopamine metabolites were high. A marked sympathetic nervous activation, more pronounced in women and in those with hydrocephalus, occurs following subarachnoid haemorrhage. The diminished cerebral perfusion seen following subarachnoid bleeding may occur as a result of activation of central catecholaminergic neurones.

Sympathetic nervous activation following subarachnoid hemorrhage: Influence of intravenous clonidine

BACKGROUND

Subarachnoid hemorrhage is often accompanied by systemic complications and cerebral vasospasm. Elevated levels of circulating catecholamines may be involved in the pathophysiology behind these events. The alpha-2-agonist clonidine inhibits sympathetic outflow by a central mechanism. Unrestricted sympathoexcitation may be detrimental and administration of clonidine may be beneficial in these patients.

METHODS

Using isotope dilution methodology, norepinephrine kinetic determinations, comprising determination of arterial norepinephrine concentration and rates of norepinephrine spillover to and removal, or clearance, from plasma, were performed on three occasions during the first week after subarachnoid hemorrhage in 25 patients. Eleven of these patients received clonidine (continuous i.v. infusion 5.8 +/- 0.7 microg x kg(-1) x 24 h(-1)) and the remainder, standard therapy. Initial results were compared with 17 healthy age-matched subjects and eight patients suffering from severe traumatic brain injury without traumatic subarachnoid hemorrhage.

RESULTS

Subarachnoid hemorrhage patients exhibited markedly elevated arterial plasma norepinephrine concentrations [3.74 +/- 0.48, P < 0.001 vs. healthy subjects (1.59 +/- 0.11 nmol/L) and P < 0.05 vs. head trauma patients (1.94 +/- 0.29 nmol/L)]. The rate of clearance of norepinephrine from plasma in the subarachnoid patients was also significantly greater than that observed in the healthy subjects (2.66 +/- 0.15 vs. 2.14 +/- 0.15 L/min, P < 0.05) and the head trauma patients (2.00 +/- 0.12 L/min, P < 0.05). Compared with both control groups, on admission the rate of spillover of norepinephrine to plasma following subarachnoid hemorrhage was markedly elevated (9.11 +/- 1.12, P < 0.001). Clonidine treatment (continuous i.v. infusion 5.8 +/- 0.7 microg x kg(-1) x 24 h(-1)) did not reduce the increased rate of spillover of norepinephrine to plasma following subarachnoid hemorrhage.

CONCLUSION

Sympathetic nervous activity is markedly elevated following subarachnoid bleeding. Clonidine had no effect on the rate of norepinephrine spillover to, or clearance from, plasma in these patients. Clearly, further studies are required to elucidate the mechanisms responsible for generating sympathetic nervous activation following subarachnoid hemorrhage.

An outcome study of severe traumatic head injury using the "Lund therapy" with low-dose prostacyclin

BACKGROUND

There are two independent head injury outcome studies using the "Lund concept", and both showed a mortality rate of about 10%, and a favourable outcome (Glasgow outcome scale, GOS 4 and 5) of about 70%. The Lund concept aims at controlling intracranial pressure, and improving microcirculation around contusions. Intracranial pressure is controlled by maintaining a normal colloid osmotic pressure and reducing the hydrostatic capillary pressure. Microcirculation is improved by ensuring strict normovolaemia and reducing sympathetic discharge. The endogenous substance prostacyclin with its antiaggregatory/antiadhesive effects may further improve microcirculation, which finds support from a microdialysis-based clinical study and an experimental brain trauma study. The present clinical outcome study aims at evaluating whether the previously obtained good outcome with the Lund therapy can be reproduced, and whether the addition of prostacyclin has any adverse side-effects.

METHODS

All 31 consecutive patients with severe head injury, Glasgow coma scale (GCS) < or = 8, admitted to the University Hospital of Umeå during 1998 were included. The Lund therapy including prostacyclin infusion for the first three days at a dose of 0.5 ng kg(-1) min(-1). Outcome was evaluated according to the GOS >10 months after the injury.

RESULTS

One patient died, another suffered vegetative state and 7 severe disability. Of the 22 patients with favourable outcome, 19 showed good recovery and 3 moderate disability. No adverse side-effects of prostacyclin were observed.

CONCLUSION

The outcome results from previous studies using the Lund therapy were reproduced, and no adverse side-effects of low-dose prostacyclin were observed.

Increased sympathetic nervous activity in patients with nontraumatic subarachnoid hemorrhage

BACKGROUND AND PURPOSE

Activation of the sympathetic nervous system, which leads to elevation of circulating catecholamines, is implicated in the genesis of cerebral vasospasm and cardiac aberrations after subarachnoid hemorrhage. To this juncture, sympathetic nervous testing has relied on indirect methods only.

METHODS

We used an isotope dilution technique to estimate the magnitude and time course of sympathoadrenal activation in 18 subarachnoid patients.

RESULTS

Compared with 2 different control groups, the patients with subarachnoid hemorrhage exhibited an approximately 3-fold increase in total-body norepinephrine spillover into plasma within 48 hours after insult (3.2+/-0.3 and 4.2+/-0.7 versus 10.2+/-1.4 nmol/L; P<0.05 versus both). This sympathetic activation persisted throughout the 7- to 10-day examination period and was normalized at the 6-month follow-up visit.

CONCLUSIONS

The present study has established that massive sympathetic nervous activation occurs in patients after subarachnoid hemorrhage. This overactivation may relate to the well-known cardiac complications described in subarachnoid hemorrhage.

A standardized neurosurgical neurointensive therapy directed toward vasogenic edema after severe traumatic brain injury: clinical results

OBJECTIVE

Analysis of a standardized therapy focusing on prevention and treatment of vasogenic edema in patients suffering severe traumatic brain injury (TBI).

DESIGN

A retrospective analysis.

SETTING

Neurointensive care unit at Sahlgrenska University Hospital, Göteborg, Sweden.

PATIENTS

38 patients with severe TBI were included. The median Glasgow Coma Score was 5 (range 3-8) and median age 27 years (range 5-70 years).

INTERVENTIONS

Measurement of intracranial pressure (ICP). Surgical evacuation of hematomas and contusions. Volume expansion aiming at normovolemia. Sedation with continuous intravenous infusion of low-dose thiopentone and reduction of stress response by clonidine. Normalization of capillary hydrostatic pressure by metoprolol and clonidine. If ICP and cerebral perfusion pressure (CPP) were not stabilized (ICP < 20 mmHg and CPP > 60 mm Hg), a continuous infusion of dihydroergotamine was added. In 4 patients a craniectomy was performed.

RESULTS

Of the 38 patients, 27 (71%) survived with good recovery or moderate disability, 5 (13%) survived with severe disability, 1 (3%) remained in a vegetative state, and 5 (13%) died. The mortality due to intracranial hypertension was 11% (4 patients).

CONCLUSION

A therapy focusing on treatment of the assumed vasogenic edema in combination with aggressive neurosurgery resulted in an outcome as good as the best previously reported.

Instillation of alcohol into venous malformations of the head and neck

Vascular malformations are errors of vascular morphogenesis, and must be differentiated from vascular tumours such as haemangiomas, because the natural history and treatment are different. Vascular malformations may be arteriovenous with high blood flow, or venous with low blood flow. Venous vascular malformations grow among soft tissues and are difficult to delineate at operation. Direct puncture under fluoroscopy with injection of contrast medium is one method of visualising the cavities of a venous malformation. Instillation of concentrated alcohol directly into such cavities is a possible treatment. Forty-four patients with venous malformations of the head or neck have been treated since 1984, of whom 31 responded to a follow up questionnaire. Twenty-three responded to injection of ethanol alone, and eight also required reconstructive surgery; 26 of the 31 described the result as "good" or "excellent" (84%).