A J Johnston
Affiliation: University of Cambridge
- Effect of cerebral perfusion pressure augmentation with dopamine and norepinephrine on global and focal brain oxygenation after traumatic brain injuryAndrew J Johnston
Department of Anaesthetics, University of Cambridge, Addenbrooke s Hospital, Box 93, Cambridge CB2 2QQ, UK
Intensive Care Med 30:791-7. 2004..To compare the effects of a cerebral perfusion pressure (CPP) intervention achieved with dopamine and norepinephrine after severe head injury...
- Hyperoxia and the cerebral hemodynamic responses to moderate hyperventilationA J Johnston
Department of Anaesthetics, Addenbrooke s Hospital, University of Cambridge, Academic Neurosurgery, Addenbrooke s Hospital, Cambridge, UK
Acta Anaesthesiol Scand 47:391-6. 2003..Hyperoxia is thought to modulate the production of lactic acid. This study examined the kinetics of middle cerebral artery flow velocity (MCA FV) reduction during hyperventilation, and its modulation by hyperoxia...
- Cerebral oxygen vasoreactivity and cerebral tissue oxygen reactivityA J Johnston
University of Cambridge Department of Anaesthetics, Box 93 and Academic Neurosurgery, Addenbrooke s Hospital, Cambridge CB2 2QQ, UK
Br J Anaesth 90:774-86. 2003..This overview summarizes the available information in this area and suggests some avenues for further research...
- Effects of propofol on cerebral oxygenation and metabolism after head injuryA J Johnston
University of Cambridge Department of Anaesthesia, Box 93, Cambridge CB2 2QQ, UK
Br J Anaesth 91:781-6. 2003..We have used a step increase in target plasma propofol concentration in head injured patients to explore flow-metabolism coupling in these patients...
- Pharmacokinetics and pharmacodynamics of dopamine and norepinephrine in critically ill head-injured patientsAndrew J Johnston
University of Cambridge Department of Anaesthetics, Addenbrooke s Hospital, Box 93, Cambridge, CB2 2QQ, United Kingdom
Intensive Care Med 30:45-50. 2004..To explore the pharmacokinetics and pharmacodynamics of dopamine and norepinephrine...
- Imaging of cerebral blood flow and metabolism in brain injury in the ICUJ D Pickard
Wolfson Brain Imaging Centre, University of Cambridge, Addenbrookes Hospital, Cambridge, UK
Acta Neurochir Suppl 95:459-64. 2005..New modelling and analytical approaches have been developed...
- Effects of moderate hyperventilation on cerebrovascular pressure-reactivity after head injuryL A Steiner
Academic Neurosurgery, Addenbrooke s Hospital, Cambridge, UK
Acta Neurochir Suppl 95:17-20. 2005..Our data suggest that the response of pressure reactivity to hyperventilation is heterogeneous. This could be due to hyperventilation-induced changes in cerebral metabolism, or the change in CPP...
- Physiological thresholds for irreversible tissue damage in contusional regions following traumatic brain injuryA S Cunningham
Division of Anaesthesia, Department of Medicine, University of Cambridge, Cambridge, UK
Brain 128:1931-42. 2005..At a voxel-based level, however (and in common with ischaemic stroke), the extent of irreversible tissue damage cannot be accurately predicted by early abnormalities of any single physiological variable...
- Predicting the response of intracranial pressure to moderate hyperventilationL A Steiner
Academic Neurosurgery, Addenbrooke s Hospital, Cambridge, United Kingdom
Acta Neurochir (Wien) 147:477-83; discussion 483. 2005..We investigated the ability of pre-hyperventilation ICP and cerebrospinal compensatory reserve to predict the reduction in ICP achievable with moderate hyperventilation in head injured patients...
- Evaluation of the Sherlock 3CG Tip Confirmation System on peripherally inserted central catheter malposition ratesA J Johnston
John Farman Intensive Care Unit, Addenbrooke s Hospital, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
Anaesthesia 69:1322-30. 2014..5%; 95% CI 16-26%) catheters were malpositioned. These malposition rates are significantly lower than our own historical data, which used a 'blind' anthropometric technique to guide peripherally inserted central catheter insertion. ..
- Defining peripherally inserted central catheter tip position and an evaluation of insertions in one unitA J Johnston
John Farman Intensive Care Unit, Cambridge University Hospitals NHS Foundation Trust, Cambridge, UK
Anaesthesia 68:484-91. 2013..Malposition rates were significantly higher in ICU patients. Emerging technologies may assist in reducing these high rates...
- Influence of improved teaching on medical students' acquisition and retention of drug administration skillsD W Wheeler
University Department of Anaesthesia, University of Cambridge, Addenbrooke s Hospital, Cambridge CB2 2QQ, UK
Br J Anaesth 96:48-52. 2006..Lack of education about drug administration appears to be a causative factor. We devised an online teaching module for medical students and assessed its short- and long-term efficacy...
- Validation of a tonometric noninvasive arterial blood pressure monitor in the intensive care settingL A Steiner
University Department of Anaesthesia and Academic Neurosurgery, Box 167, Addenbrooke s Hospital, Cambridge CB2 2QQ, UK
Anaesthesia 58:448-54. 2003..Furthermore, there was a tendency to underestimate low pressures and overestimate high pressures. In our opinion, the Colin CBM-7000 cannot be recommended for continuous blood pressure monitoring in the intensive care setting...
- Effect of cerebral perfusion pressure augmentation on regional oxygenation and metabolism after head injuryAndrew J Johnston
University Department of Anaesthetics, Addenbrooke s Hospital, Cambridge, UK
Crit Care Med 33:189-95; discussion 255-7. 2005....
- Sustained moderate reductions in arterial CO2 after brain trauma time-course of cerebral blood flow velocity and intracranial pressureLuzius A Steiner
Department of Anaesthesia, University Hospital Basel, 4031 Basel, Switzerland
Intensive Care Med 30:2180-7. 2004..We investigated the time-course of changes in middle cerebral artery mean flow velocity (FVm) and intracranial pressure (ICP) in head-injured patients during sustained moderate reductions in arterial partial pressure of CO(2) (PaCO(2))...
- Problems encountered with a pilot online attendance record and feedback scheme for medical studentsDaniel W Wheeler
University Department of Anaesthesia, University of Cambridge, Addenbrooke s Hospital, Cambridge, UK
Educ Health (Abingdon) 19:369-74. 2006
- Does induced hypertension reduce cerebral ischaemia within the traumatized human brain?Jonathan P Coles
Division of Anaesthesia, Addenbrooke s Hospital, Cambridge, UK
Brain 127:2479-90. 2004..It also remains unclear whether CPP values below 65 mmHg can be safely used in this population. Clarification of the significance of a reduction in CMRO2 and neuronal electrical function will require further study...
- Direct comparison of cerebrovascular effects of norepinephrine and dopamine in head-injured patientsLuzius A Steiner
Academic Neurosurgery, Addenbrooke s Hospital, Cambridge, UK
Crit Care Med 32:1049-54. 2004..To directly compare the cerebrovascular effects of norepinephrine and dopamine in patients with acute traumatic brain injury...
- Incidence and mechanisms of cerebral ischemia in early clinical head injuryJonathan P Coles
The Division of Anaesthesia, and The Wolfson Brain Imaging Centre, University of Cambridge, Addenbrooke s Hospital, Cambridge, UK
J Cereb Blood Flow Metab 24:202-11. 2004..The ischemic burden represented by this "traumatic penumbra" is poorly detected by bedside clinical monitors and has significant associations with outcome...
- Measuring cerebral autoregulation in stroke patientsAndrew J Johnston
Stroke 34:e39-40; author reply e39-40. 2003
- Responses of posttraumatic pericontusional cerebral blood flow and blood volume to an increase in cerebral perfusion pressureLuzius A Steiner
Wolfson Brain Imaging Centre, University Department of Anesthesia, Academic Neurosurgery, Addenbrooke s Hospital, Cambridge, UK
J Cereb Blood Flow Metab 23:1371-7. 2003..Pericontusional oedema on computed tomography was associated with lower absolute values of CBF and CBV but did not differ from nonoedematous tissue in the relative response to CPP elevation...
- The effects of large-dose propofol on cerebrovascular pressure autoregulation in head-injured patientsLuzius A Steiner
Academic Neurosurgery, University Department of Anaesthesia, Addenbrooke s Hospital, Cambridge, United Kingdom
Anesth Analg 97:572-6, table of contents. 2003..We propose that large doses of propofol should be used cautiously in head-injured patients, because there is the potential to increase the injured brain's vulnerability to secondary insults...
- Assessment of cerebrovascular autoregulation in head-injured patients: a validation studyLuzius A Steiner
Wolfson Brain Imaging Centre, Addenbrooke s Hospital, Cambridge, UK
Stroke 34:2404-9. 2003..Cerebrovascular autoregulation is frequently measured in head-injured patients. We attempted to validate 4 bedside methods used for assessment of autoregulation...
- Hyperglycemia and brain tissue pH after traumatic brain injuryDavid A Zygun
Neuroscience Critical Care Unit and Department of Anaesthesia, University of Cambridge, Cambridge, England
Neurosurgery 55:877-81; discussion 882. 2004..We tested the hypothesis that blood glucose levels are associated with brain tissue pH (pH(b)) and that the correction of hyperglycemia would result in an improvement in pH(b)...
- Extracellular Brain pH and Outcome following Severe Traumatic Brain InjuryArun K Gupta
Neuroscience Critical Care Unit, University of Cambridge Department of Anaesthesia, UK
J Neurotrauma 21:678-84. 2004..pH(b) differentiated between survivors and non-survivors. Measurement of pH(b) may be a useful indicator of outcome in patients with TBI...
- Advanced monitoring in the neurology intensive care unit: microdialysisAndrew J Johnston
Neuro Critical Care Unit, Addenbrooke s Hospital, Cambridge, UK
Curr Opin Crit Care 8:121-7. 2002..The advantages and disadvantages of microdialysis are discussed, as is its future potential...