Jan Glover Bengtsson - Academia.edu (original) (raw)
Papers by Jan Glover Bengtsson
BJA: British Journal of Anaesthesia, 1992
In order to evaluate the value of the inspirator/ to end-tidal oxygen concentration difference ('... more In order to evaluate the value of the inspirator/ to end-tidal oxygen concentration difference ('o^E'oJ as a monitor during general anaesthesia, we studied 40 orthopaedic patients allocated randomly to four groups: anaesthesia with enf/urane or isoflurane in nitrous oxide with either spontaneous or controlled ventilation. (l Oi-^oJ followed an asymptotically increasing curve because of decreasing uptake of nitrous oxide. At 1 h, (l Oi-^oJ approached the end-tidal carbon dioxide concentration (t COi). During spontaneous ventilation, ('oj-^oj correlated best with t COi. During controlled ventilation, there was a negative correlation between (lo 2-^oj anc > nitrous oxide uptake rate. Changes in oxygen uptake rate were reflected in (io 2-£'o 2)' provided that the total ventilation volume was constant and the nitrous oxide uptake rate approached steady state conditions.
SUMMARYBackgroundAspirin has been proposed as a treatment for COVID-19 on the basis of its antith... more SUMMARYBackgroundAspirin has been proposed as a treatment for COVID-19 on the basis of its antithrombotic properties.MethodsIn this randomised, controlled, open-label platform trial, several possible treatments were compared with usual care in patients hospitalised with COVID-19. Eligible and consenting adults were randomly allocated in a 1:1 ratio to either usual standard of care plus 150mg aspirin once daily until discharge or usual standard of care alone using web-based simple (unstratified) randomisation with allocation concealment. The primary outcome was 28-day mortality. The trial is registered with ISRCTN (50189673) and clinicaltrials.gov (NCT04381936).FindingsBetween 01 November 2020 and 21 March 2021, 7351 patients were randomly allocated to receive aspirin and 7541 patients to receive usual care alone. Overall, 1222 (17%) patients allocated to aspirin and 1299 (17%) patients allocated to usual care died within 28 days (rate ratio 0·96; 95% confidence interval [CI] 0·89-1·...
The Lancet
In this study, we aimed to evaluate the effects of tocilizumab in adult patients admitted to hosp... more In this study, we aimed to evaluate the effects of tocilizumab in adult patients admitted to hospital with COVID-19 with both hypoxia and systemic inflammation. This randomised, controlled, open-label, platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]), is assessing several possible treatments in patients hospitalised with COVID-19 in the UK. Those trial participants with hypoxia (oxygen saturation <92% on air or requiring oxygen therapy) and evidence of systemic inflammation (C-reactive protein ≥75 mg/L) were eligible for random assignment in a 1:1 ratio to usual standard of care alone versus usual standard of care plus tocilizumab at a dose of 400 mg-800 mg (depending on weight) given intravenously. A second dose could be given 12-24 h later if the patient's condition had not improved. The primary outcome was 28-day mortality, assessed in the intention-to-treat population. The trial is registered with ISRCTN (50189673) and ClinicalTrials.gov (NCT04381936). Between April 23, 2020, and Jan 24, 2021, 4116 adults of 21 550 patients enrolled into the RECOVERY trial were included in the assessment of tocilizumab, including 3385 (82%) patients receiving systemic corticosteroids. Overall, 621 (31%) of the 2022 patients allocated tocilizumab and 729 (35%) of the 2094 patients allocated to usual care died within 28 days (rate ratio 0·85; 95% CI 0·76-0·94; p=0·0028). Consistent results were seen in all prespecified subgroups of patients, including those receiving systemic corticosteroids. Patients allocated to tocilizumab were more likely to be discharged from hospital within 28 days (57% vs 50%; rate ratio 1·22; 1·12-1·33; p<0·0001). Among those not receiving invasive mechanical ventilation at baseline, patients allocated tocilizumab were less likely to reach the composite endpoint of invasive mechanical ventilation or death (35% vs 42%; risk ratio 0·84; 95% CI 0·77-0·92; p<0·0001). In hospitalised COVID-19 patients with hypoxia and systemic inflammation, tocilizumab improved survival and other clinical outcomes. These benefits were seen regardless of the amount of respiratory support and were additional to the benefits of systemic corticosteroids. UK Research and Innovation (Medical Research Council) and National Institute of Health Research.
The Lancet
Background Many patients with COVID-19 have been treated with plasma containing anti-SARS-CoV-2 a... more Background Many patients with COVID-19 have been treated with plasma containing anti-SARS-CoV-2 antibodies. We aimed to evaluate the safety and efficacy of convalescent plasma therapy in patients admitted to hospital with COVID-19. Methods This randomised, controlled, open-label, platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]) is assessing several possible treatments in patients hospitalised with COVID-19 in the UK. The trial is underway at 177 NHS hospitals from across the UK. Eligible and consenting patients were randomly assigned (1:1) to receive either usual care alone (usual care group) or usual care plus high-titre convalescent plasma (convalescent plasma group). The primary outcome was 28-day mortality, analysed on an intention-to-treat basis. The trial is registered with ISRCTN, 50189673, and ClinicalTrials.gov, NCT04381936. Findings Between May 28, 2020, and Jan 15, 2021, 11558 (71%) of 16287 patients enrolled in RECOVERY were eligible to receive conva...
Der Anaesthesist, 1993
The estimation of oxygen consumption and carbon dioxide elimination is essential for predicting t... more The estimation of oxygen consumption and carbon dioxide elimination is essential for predicting the metabolic activity and needs of any patient having anaesthesia. During anaesthesia oxygen consumption can be measured and compared to a predicted value. However, oxygen uptake is affected by anaesthetic agents, which complicates the interpretation of measured oxygen uptake rate. The purpose of this study was to investigate whether there are any differences in respiratory gas exchange during anaesthesia with enflurane and isoflurane and also to assess the effects of spontaneous versus controlled ventilation. METHODS. Forty orthopedic patients were randomized to enflurane or isoflurane anaesthesia in nitrous oxide with either spontaneous or controlled ventilation. A fresh low-gas-flow technique was used. Inspiratory oxygen and end-tidal carbon dioxide concentrations and expiratory minute ventilation were measured in a circle absorber system between the y-piece and the endotracheal tube ...
Pediatric Anesthesia, 2001
Fourteen children aged 4-15 months were studied after corrective cardiac surgery. Heart rate was ... more Fourteen children aged 4-15 months were studied after corrective cardiac surgery. Heart rate was increased by 20% with an external pacemaker. Cardiac output (CO) was measured with thermodilution. Oxygen saturation was measured in systemic artery (SaO2), central vein (ScvcO2) and pulmonary artery (SvO2). Inspiratory to endtidal oxygen difference (FI-ETO2) was measured using a paramagnetic technique. SvO2 was measured continuously using a spectrophotometric technique. CO increased in three patients and decreased in 11 patients during pacing. Regression between DeltaCO and Delta(1/Sa-vO2), Delta(FI-ETO2/Sa-vO2), Delta(FI-ETO2/Sa-cvcO2) showed r=0.70, r=0.76 and r=0.75, respectively. DeltaCO exceeded 10% in 17 of 26 interventions. Changes in FI-ETO2 of equal direction as changes in CO occurred in 12 of these 17 interventions. Estimations of CO changes, based on SvO2, can be enhanced if changes in FI-ETO2 are also measured. ScvcO2 instead of SvO2 gives equivalent results. Sudden changes in FI-ETO2 after pacemaker initiation or termination can predict the direction of CO changes.
Journal of Clinical Monitoring, 1993
Objective. The purpose of this investigation was to study the N 2 flux between the patient and th... more Objective. The purpose of this investigation was to study the N 2 flux between the patient and the breathing circuit, and the excess gas during N20 anesthesia with the low, fresh gas flow technique. Methods. Forty patients were studied. After a 6-minute high, fresh gas flow denitrogenation period, the 02 fresh gas flow was set at about 4 ml/kg/min and the N20 fresh gas flow was set to maintain an inspired O 2 fraction of 0.30. The excess gas flow and N 2 excretion were measured by a variant of the Douglas bag method. Resuits. The mean inspired N2 concentration reached a peak of 5.9% at 40 minutes. The estimated mean N 2 excretion was 39 ml/min at 10 minutes, declining to 18 ml/min at 60 minutes. A calculation of N2 homeostasis during closed-circuit anesthesia based on the results of the patient study indicated that sampling for gas analysis actually reduces the gas costs if the sampled gas is scavenged instead of returned to the circle system, since intermittent flushing with high, fresh gas flow for denitrogenation is unnecessary in the former situation. Conclusions. Regardless of the fresh gas flow used, sampled gas need not be returned during Y20 anesthesia.
Intensive Care Medicine, 1996
Bronchoscopy has been used for evaluation of the potential problems of the airways and for invest... more Bronchoscopy has been used for evaluation of the potential problems of the airways and for investigation the bronchial specimens for diagnostic purposes. Recent technical advances result in performing this procedure at the bedside manner and in critically ill patients. We have performed 150 bronchoscopy during last three years on 1362 pediatric patients with respiratory problems. In 90% of cases the opentube bronchoscopy was performed (for diagnostic as well as for therapeutic reasons) and collected secretions or bioptic material were examined. The indications were: acute upper respiratory problems, chronic wheezing, inspiratory stridor, tracheal or bronchial bleeding, chronic cough, retractable atelectasis, severe pulmonary infections, lymph node perforation in lung tuberculosis and sequells like bronchiectasis and fibrosis. Our results were: anatomical malformations in 10%, mucosal oedema with chronic inflammation and thick secretions in 56%, caseos masses in 11%, granulation tissue and purulent secretions in foreign bodies and bronchiectasis in 16%, and only 7% of cases were normal finding. Our experiences pointed that this invasive procedure in carefully selected patients has important role in establishing the diagnosis and in therapeutic management of respiratory problems.
BJA: British Journal of Anaesthesia, 1994
We assessed the inspiratory to end-tidal oxygen difference (Plo 2-P E 'oJ during voluntary hyperv... more We assessed the inspiratory to end-tidal oxygen difference (Plo 2-P E 'oJ during voluntary hyperventilation in 10 healthy male volunteers. The oxygen difference was measured with a fastresponse paramagnetic differential oxygen sensor. As simultaneous changes in metabolism and cardiac output also influence (Pioj-P^oJ. oxygen uptake was measured with indirect calorimetry and noninvasive transthoracic electrical bioimpedance was used for measurement of cardiac output. After a rest period, subjects were instructed to double their minute ventilation volume (VE) and after 5 min triple their resting Vf for another 5 min. (Plo,-PE'OJ decreased from a zero value of 6.4 kPa to 3.9 kPa at 5 min (?<0.01) and 2.9 kPa at 70 min (P < 0.01). At 15 min (i.e. 5 min after the end of hyperventilation) there was an increase in (Pioj-P^oJ to 8.3kPa (P<0.05). Regression analysis between (Plo 7-PE' O J (kPa) and VE (litre m' 2 min-') gave the formula: (Pl 02-P? 0 J = 11 (0.059+0.034VE), r =-0.S2, n=158. Oxygen uptake and cardiac output did not change significantly during hyperventilation, but decreased in the post-hyperventilation period. An oxygen difference of more than 8 kPa was associated with significant arterial desaturation.
Pediatric Critical Care Medicine, 2002
Simple, preferably noninvasive measurements of cardiac output are useful in pediatric patients re... more Simple, preferably noninvasive measurements of cardiac output are useful in pediatric patients receiving inotropic support. Oxygen saturation in pulmonary artery (Svo(2)) gives information about oxygen delivery and demand. Many inotropic drugs influence oxygen consumption. When effects on Svo(2) are studied, after a change in inotropic drug dosage, a change in oxygen consumption needs to be considered to accurately estimate the change in cardiac output. The aim of this investigation was to study whether information on inspired to end-tidal oxygen concentration difference (Fi-eto(2)) in addition to Svo(2) would improve estimation of changes in cardiac output. Prospective observational study of Fi-eto(2), Svo(2), and oxygen saturation from central vein (Scvco(2)) for measurements of circulatory and metabolic effects of changes in dopamine dosage. Intensive care unit in a children's hospital. Twenty patients (age 4 days to 98 months) were studied after cardiac surgery. Dopamine was...
Acta Anaesthesiologica Scandinavica, 1995
ABSTRACT Background. The paramagnetic technique has made it possible to monitor the end-tidal oxy... more ABSTRACT Background. The paramagnetic technique has made it possible to monitor the end-tidal oxygen concentration and P(I-ET)O2, i. e. inspiratory to end-tidal oxygen difference, breath-by-breath. Little is known about the implications of a changing P(I-ET)O2, but so far studies have shown it to be a quick and sensitive variable to detect hypoventilation. This study was designed to observe the circulatory effects on P(I-ET)O2 in an experimental setting but monitored as in a clinical situation.Methods. We assessed the oxygen difference during changes in cardiac output induced by intravenous ephedrine-hydrochloride in 12 healthy male volunteers. P(I-ET)O2 was measured with a fast-response paramagnetic differential oxygen sensor. Cardiac output was measured with non-invasive transthoracie electrical bioimpedance. As stimultaneous changes in metabolism and ventilation will also influence P(I-ET)O2, oxygen uptake and expired minute volume were monitored. After a rest period, the subjects had an intravenous injection of ephedrine-hydrochloride 0.1 mg·kg-1 followed by a 30-min observation period.Results. Cardiac output increased significantly as did the oxygen uptake and the ventilation. We found no biologically significant correlation between cardiac output and P(I-ET)O2. The P(I-ET)O2 was influenced by ventilation and metabolism.
Acta Anaesthesiologica Scandinavica, 1995
Bolus doses of ephedrine are often used by anaesthesiologists for intraoperative hypotension. Thi... more Bolus doses of ephedrine are often used by anaesthesiologists for intraoperative hypotension. This randomized single-blind cross-over study was designed to simultaneously evaluate circulatory, respiratory and metabolic effects of intravenously given ephedrine in 12 healthy male volunteers. Oxygen uptake and carbon dioxide excretion were measured with indirect calorimetry and non-invasive transthoracic electrical bioimpedance was used for cardiac output measurements. The maximum effect on most variables was reached at 4-5 min. At 5 min after the administration of ephedrine 0.1 mg per kilogram body weight, there were significant increases in cardiac index, systolic and mean arterial blood pressure, expired minute volume, oxygen uptake and carbon dioxide excretion rates. There were no significant changes in the quotient between oxygen uptake rate and cardiac index, VO2/CI during the 30 min study period. The O2 saturation was not altered. The present study indicates that ephedrine increases oxygen demand and supply in a similar magnitude.
Acta Anaesthesiologica Scandinavica, 2001
Background: ''Ideal'' alveolar oxygen tension (PAO 2) is a calculated entity and the alveolar-art... more Background: ''Ideal'' alveolar oxygen tension (PAO 2) is a calculated entity and the alveolar-arterial oxygen tension difference (PA-aO 2) is used to evaluate gas exchange function of the lungs. Accurate calculations of PAO 2 necessitate measurements of the respiratory exchange ratio (RER), which is less frequently done, and most often approximations are made. The measured endtidal oxygen tension (PETO 2) is a reflection of the alveolar oxygen tension. The aim was to study the relationship between PAO 2 and PETO 2 , and to see whether the end-tidal to arterial oxygen tension difference (PET-aO 2) could give the same information about lung function as PA-aO 2. Methods: Twenty patients admitted for cardio-pulmonary exercise tests were studied. They bicycled for 4 min at each work load until maximum work load was reached. Arterial blood gases were analysed before, after 4 min at each work load, at maximum work load and after 2 min of recovery. A metabolic computer measured mixed expired gas concentrations. Endtidal gas concentrations were measured with a side stream gas analyser.
Pediatric Critical Care Medicine, 2010
To assess patient safety and to evaluate operator acceptance to the technology of neurally adjust... more To assess patient safety and to evaluate operator acceptance to the technology of neurally adjusted ventilatory assist. A within-patient crossover study. A ten-bed tertiary care university hospital pediatric intensive care unit. A total of 21 mechanically ventilated infants and children aged 2 days to 15 yrs suffering from a variety of disorders. The majority of patients were treated after cardiac surgery. In patients with pressure-support ventilation, a nasogastric neurally adjusted ventilatory assist catheter was positioned to detect the diaphragm electrical impulse. Initiation and termination of ventilatory support for each breath could then be regulated either through conventional volume or pressure changes or through changes in the detected diaphragm electrical impulse signal. Ventilation was started as pressure-support ventilation for 30 mins, changed to neurally adjusted ventilatory assist for 30 mins, switched back to pressure-support ventilation for 30 mins and then neurally adjusted ventilatory assist until an end-point criterion was reached. There were no serious adverse events during the study and all patients were circulatory and respiratory stable. The neurally adjusted ventilatory assist catheter was easy to place. The treatment time with neurally adjusted ventilatory assist ranged from 1 to 8 hrs (median = 2.5 hrs). During neurally adjusted ventilatory assist, the peak airway pressures decreased as compared with pressure-support mode but the mean airway pressures were not significantly changed.The respiratory rates increased during neurally adjusted ventilatory assist. The neural trigger on was first in 68% (median) whereas the neural trigger off was first in 88% (median) as compared with the pneumatic trigger on and off. Eight of the patients could be extubated in close connection to the termination of the neurally adjusted ventilatory assist treatment. We feel that neurally adjusted ventilatory assist would be safe and potentially efficacious to ventilate infants and children. It has the potential for improved patient-ventilator synchrony, decreasing airway pressures, and it might lead to earlier extubation.
The Lancet
Azithromycin has been proposed as a treatment for COVID-19 on the basis of its immunomodulatory a... more Azithromycin has been proposed as a treatment for COVID-19 on the basis of its immunomodulatory actions. We aimed to evaluate the safety and efficacy of azithromycin in patients admitted to hospital with COVID-19. In this randomised, controlled, open-label, adaptive platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]), several possible treatments were compared with usual care in patients admitted to hospital with COVID-19 in the UK. The trial is underway at 176 hospitals in the UK. Eligible and consenting patients were randomly allocated to either usual standard of care alone or usual standard of care plus azithromycin 500 mg once per day by mouth or intravenously for 10 days or until discharge (or allocation to one of the other RECOVERY treatment groups). Patients were assigned via web-based simple (unstratified) randomisation with allocation concealment and were twice as likely to be randomly assigned to usual care than to any of the active treatment groups. Participants and local study staff were not masked to the allocated treatment, but all others involved in the trial were masked to the outcome data during the trial. The primary outcome was 28-day all-cause mortality, assessed in the intention-to-treat population. The trial is registered with ISRCTN, 50189673, and ClinicalTrials.gov, NCT04381936. Between April 7 and Nov 27, 2020, of 16 442 patients enrolled in the RECOVERY trial, 9433 (57%) were eligible and 7763 were included in the assessment of azithromycin. The mean age of these study participants was 65·3 years (SD 15·7) and approximately a third were women (2944 [38%] of 7763). 2582 patients were randomly allocated to receive azithromycin and 5181 patients were randomly allocated to usual care alone. Overall, 561 (22%) patients allocated to azithromycin and 1162 (22%) patients allocated to usual care died within 28 days (rate ratio 0·97, 95% CI 0·87-1·07; p=0·50). No significant difference was seen in duration of hospital stay (median 10 days [IQR 5 to >28] vs 11 days [5 to >28]) or the proportion of patients discharged from hospital alive within 28 days (rate ratio 1·04, 95% CI 0·98-1·10; p=0·19). Among those not on invasive mechanical ventilation at baseline, no significant difference was seen in the proportion meeting the composite endpoint of invasive mechanical ventilation or death (risk ratio 0·95, 95% CI 0·87-1·03; p=0·24). In patients admitted to hospital with COVID-19, azithromycin did not improve survival or other prespecified clinical outcomes. Azithromycin use in patients admitted to hospital with COVID-19 should be restricted to patients in whom there is a clear antimicrobial indication. UK Research and Innovation (Medical Research Council) and National Institute of Health Research.
BJA: British Journal of Anaesthesia, 1992
In order to evaluate the value of the inspirator/ to end-tidal oxygen concentration difference ('... more In order to evaluate the value of the inspirator/ to end-tidal oxygen concentration difference ('o^E'oJ as a monitor during general anaesthesia, we studied 40 orthopaedic patients allocated randomly to four groups: anaesthesia with enf/urane or isoflurane in nitrous oxide with either spontaneous or controlled ventilation. (l Oi-^oJ followed an asymptotically increasing curve because of decreasing uptake of nitrous oxide. At 1 h, (l Oi-^oJ approached the end-tidal carbon dioxide concentration (t COi). During spontaneous ventilation, ('oj-^oj correlated best with t COi. During controlled ventilation, there was a negative correlation between (lo 2-^oj anc > nitrous oxide uptake rate. Changes in oxygen uptake rate were reflected in (io 2-£'o 2)' provided that the total ventilation volume was constant and the nitrous oxide uptake rate approached steady state conditions.
SUMMARYBackgroundAspirin has been proposed as a treatment for COVID-19 on the basis of its antith... more SUMMARYBackgroundAspirin has been proposed as a treatment for COVID-19 on the basis of its antithrombotic properties.MethodsIn this randomised, controlled, open-label platform trial, several possible treatments were compared with usual care in patients hospitalised with COVID-19. Eligible and consenting adults were randomly allocated in a 1:1 ratio to either usual standard of care plus 150mg aspirin once daily until discharge or usual standard of care alone using web-based simple (unstratified) randomisation with allocation concealment. The primary outcome was 28-day mortality. The trial is registered with ISRCTN (50189673) and clinicaltrials.gov (NCT04381936).FindingsBetween 01 November 2020 and 21 March 2021, 7351 patients were randomly allocated to receive aspirin and 7541 patients to receive usual care alone. Overall, 1222 (17%) patients allocated to aspirin and 1299 (17%) patients allocated to usual care died within 28 days (rate ratio 0·96; 95% confidence interval [CI] 0·89-1·...
The Lancet
In this study, we aimed to evaluate the effects of tocilizumab in adult patients admitted to hosp... more In this study, we aimed to evaluate the effects of tocilizumab in adult patients admitted to hospital with COVID-19 with both hypoxia and systemic inflammation. This randomised, controlled, open-label, platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]), is assessing several possible treatments in patients hospitalised with COVID-19 in the UK. Those trial participants with hypoxia (oxygen saturation <92% on air or requiring oxygen therapy) and evidence of systemic inflammation (C-reactive protein ≥75 mg/L) were eligible for random assignment in a 1:1 ratio to usual standard of care alone versus usual standard of care plus tocilizumab at a dose of 400 mg-800 mg (depending on weight) given intravenously. A second dose could be given 12-24 h later if the patient's condition had not improved. The primary outcome was 28-day mortality, assessed in the intention-to-treat population. The trial is registered with ISRCTN (50189673) and ClinicalTrials.gov (NCT04381936). Between April 23, 2020, and Jan 24, 2021, 4116 adults of 21 550 patients enrolled into the RECOVERY trial were included in the assessment of tocilizumab, including 3385 (82%) patients receiving systemic corticosteroids. Overall, 621 (31%) of the 2022 patients allocated tocilizumab and 729 (35%) of the 2094 patients allocated to usual care died within 28 days (rate ratio 0·85; 95% CI 0·76-0·94; p=0·0028). Consistent results were seen in all prespecified subgroups of patients, including those receiving systemic corticosteroids. Patients allocated to tocilizumab were more likely to be discharged from hospital within 28 days (57% vs 50%; rate ratio 1·22; 1·12-1·33; p<0·0001). Among those not receiving invasive mechanical ventilation at baseline, patients allocated tocilizumab were less likely to reach the composite endpoint of invasive mechanical ventilation or death (35% vs 42%; risk ratio 0·84; 95% CI 0·77-0·92; p<0·0001). In hospitalised COVID-19 patients with hypoxia and systemic inflammation, tocilizumab improved survival and other clinical outcomes. These benefits were seen regardless of the amount of respiratory support and were additional to the benefits of systemic corticosteroids. UK Research and Innovation (Medical Research Council) and National Institute of Health Research.
The Lancet
Background Many patients with COVID-19 have been treated with plasma containing anti-SARS-CoV-2 a... more Background Many patients with COVID-19 have been treated with plasma containing anti-SARS-CoV-2 antibodies. We aimed to evaluate the safety and efficacy of convalescent plasma therapy in patients admitted to hospital with COVID-19. Methods This randomised, controlled, open-label, platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]) is assessing several possible treatments in patients hospitalised with COVID-19 in the UK. The trial is underway at 177 NHS hospitals from across the UK. Eligible and consenting patients were randomly assigned (1:1) to receive either usual care alone (usual care group) or usual care plus high-titre convalescent plasma (convalescent plasma group). The primary outcome was 28-day mortality, analysed on an intention-to-treat basis. The trial is registered with ISRCTN, 50189673, and ClinicalTrials.gov, NCT04381936. Findings Between May 28, 2020, and Jan 15, 2021, 11558 (71%) of 16287 patients enrolled in RECOVERY were eligible to receive conva...
Der Anaesthesist, 1993
The estimation of oxygen consumption and carbon dioxide elimination is essential for predicting t... more The estimation of oxygen consumption and carbon dioxide elimination is essential for predicting the metabolic activity and needs of any patient having anaesthesia. During anaesthesia oxygen consumption can be measured and compared to a predicted value. However, oxygen uptake is affected by anaesthetic agents, which complicates the interpretation of measured oxygen uptake rate. The purpose of this study was to investigate whether there are any differences in respiratory gas exchange during anaesthesia with enflurane and isoflurane and also to assess the effects of spontaneous versus controlled ventilation. METHODS. Forty orthopedic patients were randomized to enflurane or isoflurane anaesthesia in nitrous oxide with either spontaneous or controlled ventilation. A fresh low-gas-flow technique was used. Inspiratory oxygen and end-tidal carbon dioxide concentrations and expiratory minute ventilation were measured in a circle absorber system between the y-piece and the endotracheal tube ...
Pediatric Anesthesia, 2001
Fourteen children aged 4-15 months were studied after corrective cardiac surgery. Heart rate was ... more Fourteen children aged 4-15 months were studied after corrective cardiac surgery. Heart rate was increased by 20% with an external pacemaker. Cardiac output (CO) was measured with thermodilution. Oxygen saturation was measured in systemic artery (SaO2), central vein (ScvcO2) and pulmonary artery (SvO2). Inspiratory to endtidal oxygen difference (FI-ETO2) was measured using a paramagnetic technique. SvO2 was measured continuously using a spectrophotometric technique. CO increased in three patients and decreased in 11 patients during pacing. Regression between DeltaCO and Delta(1/Sa-vO2), Delta(FI-ETO2/Sa-vO2), Delta(FI-ETO2/Sa-cvcO2) showed r=0.70, r=0.76 and r=0.75, respectively. DeltaCO exceeded 10% in 17 of 26 interventions. Changes in FI-ETO2 of equal direction as changes in CO occurred in 12 of these 17 interventions. Estimations of CO changes, based on SvO2, can be enhanced if changes in FI-ETO2 are also measured. ScvcO2 instead of SvO2 gives equivalent results. Sudden changes in FI-ETO2 after pacemaker initiation or termination can predict the direction of CO changes.
Journal of Clinical Monitoring, 1993
Objective. The purpose of this investigation was to study the N 2 flux between the patient and th... more Objective. The purpose of this investigation was to study the N 2 flux between the patient and the breathing circuit, and the excess gas during N20 anesthesia with the low, fresh gas flow technique. Methods. Forty patients were studied. After a 6-minute high, fresh gas flow denitrogenation period, the 02 fresh gas flow was set at about 4 ml/kg/min and the N20 fresh gas flow was set to maintain an inspired O 2 fraction of 0.30. The excess gas flow and N 2 excretion were measured by a variant of the Douglas bag method. Resuits. The mean inspired N2 concentration reached a peak of 5.9% at 40 minutes. The estimated mean N 2 excretion was 39 ml/min at 10 minutes, declining to 18 ml/min at 60 minutes. A calculation of N2 homeostasis during closed-circuit anesthesia based on the results of the patient study indicated that sampling for gas analysis actually reduces the gas costs if the sampled gas is scavenged instead of returned to the circle system, since intermittent flushing with high, fresh gas flow for denitrogenation is unnecessary in the former situation. Conclusions. Regardless of the fresh gas flow used, sampled gas need not be returned during Y20 anesthesia.
Intensive Care Medicine, 1996
Bronchoscopy has been used for evaluation of the potential problems of the airways and for invest... more Bronchoscopy has been used for evaluation of the potential problems of the airways and for investigation the bronchial specimens for diagnostic purposes. Recent technical advances result in performing this procedure at the bedside manner and in critically ill patients. We have performed 150 bronchoscopy during last three years on 1362 pediatric patients with respiratory problems. In 90% of cases the opentube bronchoscopy was performed (for diagnostic as well as for therapeutic reasons) and collected secretions or bioptic material were examined. The indications were: acute upper respiratory problems, chronic wheezing, inspiratory stridor, tracheal or bronchial bleeding, chronic cough, retractable atelectasis, severe pulmonary infections, lymph node perforation in lung tuberculosis and sequells like bronchiectasis and fibrosis. Our results were: anatomical malformations in 10%, mucosal oedema with chronic inflammation and thick secretions in 56%, caseos masses in 11%, granulation tissue and purulent secretions in foreign bodies and bronchiectasis in 16%, and only 7% of cases were normal finding. Our experiences pointed that this invasive procedure in carefully selected patients has important role in establishing the diagnosis and in therapeutic management of respiratory problems.
BJA: British Journal of Anaesthesia, 1994
We assessed the inspiratory to end-tidal oxygen difference (Plo 2-P E 'oJ during voluntary hyperv... more We assessed the inspiratory to end-tidal oxygen difference (Plo 2-P E 'oJ during voluntary hyperventilation in 10 healthy male volunteers. The oxygen difference was measured with a fastresponse paramagnetic differential oxygen sensor. As simultaneous changes in metabolism and cardiac output also influence (Pioj-P^oJ. oxygen uptake was measured with indirect calorimetry and noninvasive transthoracic electrical bioimpedance was used for measurement of cardiac output. After a rest period, subjects were instructed to double their minute ventilation volume (VE) and after 5 min triple their resting Vf for another 5 min. (Plo,-PE'OJ decreased from a zero value of 6.4 kPa to 3.9 kPa at 5 min (?<0.01) and 2.9 kPa at 70 min (P < 0.01). At 15 min (i.e. 5 min after the end of hyperventilation) there was an increase in (Pioj-P^oJ to 8.3kPa (P<0.05). Regression analysis between (Plo 7-PE' O J (kPa) and VE (litre m' 2 min-') gave the formula: (Pl 02-P? 0 J = 11 (0.059+0.034VE), r =-0.S2, n=158. Oxygen uptake and cardiac output did not change significantly during hyperventilation, but decreased in the post-hyperventilation period. An oxygen difference of more than 8 kPa was associated with significant arterial desaturation.
Pediatric Critical Care Medicine, 2002
Simple, preferably noninvasive measurements of cardiac output are useful in pediatric patients re... more Simple, preferably noninvasive measurements of cardiac output are useful in pediatric patients receiving inotropic support. Oxygen saturation in pulmonary artery (Svo(2)) gives information about oxygen delivery and demand. Many inotropic drugs influence oxygen consumption. When effects on Svo(2) are studied, after a change in inotropic drug dosage, a change in oxygen consumption needs to be considered to accurately estimate the change in cardiac output. The aim of this investigation was to study whether information on inspired to end-tidal oxygen concentration difference (Fi-eto(2)) in addition to Svo(2) would improve estimation of changes in cardiac output. Prospective observational study of Fi-eto(2), Svo(2), and oxygen saturation from central vein (Scvco(2)) for measurements of circulatory and metabolic effects of changes in dopamine dosage. Intensive care unit in a children's hospital. Twenty patients (age 4 days to 98 months) were studied after cardiac surgery. Dopamine was...
Acta Anaesthesiologica Scandinavica, 1995
ABSTRACT Background. The paramagnetic technique has made it possible to monitor the end-tidal oxy... more ABSTRACT Background. The paramagnetic technique has made it possible to monitor the end-tidal oxygen concentration and P(I-ET)O2, i. e. inspiratory to end-tidal oxygen difference, breath-by-breath. Little is known about the implications of a changing P(I-ET)O2, but so far studies have shown it to be a quick and sensitive variable to detect hypoventilation. This study was designed to observe the circulatory effects on P(I-ET)O2 in an experimental setting but monitored as in a clinical situation.Methods. We assessed the oxygen difference during changes in cardiac output induced by intravenous ephedrine-hydrochloride in 12 healthy male volunteers. P(I-ET)O2 was measured with a fast-response paramagnetic differential oxygen sensor. Cardiac output was measured with non-invasive transthoracie electrical bioimpedance. As stimultaneous changes in metabolism and ventilation will also influence P(I-ET)O2, oxygen uptake and expired minute volume were monitored. After a rest period, the subjects had an intravenous injection of ephedrine-hydrochloride 0.1 mg·kg-1 followed by a 30-min observation period.Results. Cardiac output increased significantly as did the oxygen uptake and the ventilation. We found no biologically significant correlation between cardiac output and P(I-ET)O2. The P(I-ET)O2 was influenced by ventilation and metabolism.
Acta Anaesthesiologica Scandinavica, 1995
Bolus doses of ephedrine are often used by anaesthesiologists for intraoperative hypotension. Thi... more Bolus doses of ephedrine are often used by anaesthesiologists for intraoperative hypotension. This randomized single-blind cross-over study was designed to simultaneously evaluate circulatory, respiratory and metabolic effects of intravenously given ephedrine in 12 healthy male volunteers. Oxygen uptake and carbon dioxide excretion were measured with indirect calorimetry and non-invasive transthoracic electrical bioimpedance was used for cardiac output measurements. The maximum effect on most variables was reached at 4-5 min. At 5 min after the administration of ephedrine 0.1 mg per kilogram body weight, there were significant increases in cardiac index, systolic and mean arterial blood pressure, expired minute volume, oxygen uptake and carbon dioxide excretion rates. There were no significant changes in the quotient between oxygen uptake rate and cardiac index, VO2/CI during the 30 min study period. The O2 saturation was not altered. The present study indicates that ephedrine increases oxygen demand and supply in a similar magnitude.
Acta Anaesthesiologica Scandinavica, 2001
Background: ''Ideal'' alveolar oxygen tension (PAO 2) is a calculated entity and the alveolar-art... more Background: ''Ideal'' alveolar oxygen tension (PAO 2) is a calculated entity and the alveolar-arterial oxygen tension difference (PA-aO 2) is used to evaluate gas exchange function of the lungs. Accurate calculations of PAO 2 necessitate measurements of the respiratory exchange ratio (RER), which is less frequently done, and most often approximations are made. The measured endtidal oxygen tension (PETO 2) is a reflection of the alveolar oxygen tension. The aim was to study the relationship between PAO 2 and PETO 2 , and to see whether the end-tidal to arterial oxygen tension difference (PET-aO 2) could give the same information about lung function as PA-aO 2. Methods: Twenty patients admitted for cardio-pulmonary exercise tests were studied. They bicycled for 4 min at each work load until maximum work load was reached. Arterial blood gases were analysed before, after 4 min at each work load, at maximum work load and after 2 min of recovery. A metabolic computer measured mixed expired gas concentrations. Endtidal gas concentrations were measured with a side stream gas analyser.
Pediatric Critical Care Medicine, 2010
To assess patient safety and to evaluate operator acceptance to the technology of neurally adjust... more To assess patient safety and to evaluate operator acceptance to the technology of neurally adjusted ventilatory assist. A within-patient crossover study. A ten-bed tertiary care university hospital pediatric intensive care unit. A total of 21 mechanically ventilated infants and children aged 2 days to 15 yrs suffering from a variety of disorders. The majority of patients were treated after cardiac surgery. In patients with pressure-support ventilation, a nasogastric neurally adjusted ventilatory assist catheter was positioned to detect the diaphragm electrical impulse. Initiation and termination of ventilatory support for each breath could then be regulated either through conventional volume or pressure changes or through changes in the detected diaphragm electrical impulse signal. Ventilation was started as pressure-support ventilation for 30 mins, changed to neurally adjusted ventilatory assist for 30 mins, switched back to pressure-support ventilation for 30 mins and then neurally adjusted ventilatory assist until an end-point criterion was reached. There were no serious adverse events during the study and all patients were circulatory and respiratory stable. The neurally adjusted ventilatory assist catheter was easy to place. The treatment time with neurally adjusted ventilatory assist ranged from 1 to 8 hrs (median = 2.5 hrs). During neurally adjusted ventilatory assist, the peak airway pressures decreased as compared with pressure-support mode but the mean airway pressures were not significantly changed.The respiratory rates increased during neurally adjusted ventilatory assist. The neural trigger on was first in 68% (median) whereas the neural trigger off was first in 88% (median) as compared with the pneumatic trigger on and off. Eight of the patients could be extubated in close connection to the termination of the neurally adjusted ventilatory assist treatment. We feel that neurally adjusted ventilatory assist would be safe and potentially efficacious to ventilate infants and children. It has the potential for improved patient-ventilator synchrony, decreasing airway pressures, and it might lead to earlier extubation.
The Lancet
Azithromycin has been proposed as a treatment for COVID-19 on the basis of its immunomodulatory a... more Azithromycin has been proposed as a treatment for COVID-19 on the basis of its immunomodulatory actions. We aimed to evaluate the safety and efficacy of azithromycin in patients admitted to hospital with COVID-19. In this randomised, controlled, open-label, adaptive platform trial (Randomised Evaluation of COVID-19 Therapy [RECOVERY]), several possible treatments were compared with usual care in patients admitted to hospital with COVID-19 in the UK. The trial is underway at 176 hospitals in the UK. Eligible and consenting patients were randomly allocated to either usual standard of care alone or usual standard of care plus azithromycin 500 mg once per day by mouth or intravenously for 10 days or until discharge (or allocation to one of the other RECOVERY treatment groups). Patients were assigned via web-based simple (unstratified) randomisation with allocation concealment and were twice as likely to be randomly assigned to usual care than to any of the active treatment groups. Participants and local study staff were not masked to the allocated treatment, but all others involved in the trial were masked to the outcome data during the trial. The primary outcome was 28-day all-cause mortality, assessed in the intention-to-treat population. The trial is registered with ISRCTN, 50189673, and ClinicalTrials.gov, NCT04381936. Between April 7 and Nov 27, 2020, of 16 442 patients enrolled in the RECOVERY trial, 9433 (57%) were eligible and 7763 were included in the assessment of azithromycin. The mean age of these study participants was 65·3 years (SD 15·7) and approximately a third were women (2944 [38%] of 7763). 2582 patients were randomly allocated to receive azithromycin and 5181 patients were randomly allocated to usual care alone. Overall, 561 (22%) patients allocated to azithromycin and 1162 (22%) patients allocated to usual care died within 28 days (rate ratio 0·97, 95% CI 0·87-1·07; p=0·50). No significant difference was seen in duration of hospital stay (median 10 days [IQR 5 to >28] vs 11 days [5 to >28]) or the proportion of patients discharged from hospital alive within 28 days (rate ratio 1·04, 95% CI 0·98-1·10; p=0·19). Among those not on invasive mechanical ventilation at baseline, no significant difference was seen in the proportion meeting the composite endpoint of invasive mechanical ventilation or death (risk ratio 0·95, 95% CI 0·87-1·03; p=0·24). In patients admitted to hospital with COVID-19, azithromycin did not improve survival or other prespecified clinical outcomes. Azithromycin use in patients admitted to hospital with COVID-19 should be restricted to patients in whom there is a clear antimicrobial indication. UK Research and Innovation (Medical Research Council) and National Institute of Health Research.