Mark Buckland - Academia.edu (original) (raw)
Papers by Mark Buckland
Anaesthesia & intensive care medicine/Anaesthesia and intensive care medicine, May 1, 2024
![Research paper thumbnail of A Comparison of Epidural Ropivacaine Infusion Alone and in Combination with 1, 2, and 4 [micro sign]g/mL Fentanyl for Seventy-Two Hours of Postoperative Analgesia After Major Abdominal Surgery](https://attachments.academia-assets.com/118284661/thumbnails/1.jpg)
](Anesthesia & Analgesia, Apr 1, 1999
Anaesthesia and Intensive Care, Apr 1, 1993
The Supervisors of Anaesthetic Training in Australia and New Zealand were surveyed and asked to r... more The Supervisors of Anaesthetic Training in Australia and New Zealand were surveyed and asked to report any cases of chemical dependence from anaesthetic registrars at their hospital from 1981 to 1991. From 83 questionnaires there were 65 (78%) returned There were 14 departments (22%) with experience of one or more cases during this interval. Only five (7%) reported conducting a lecture or tutorial on the problem. The departmental reports covered 4425 registrar years of training and there were 17 cases reported. Of these, 13 were complete and are considered in detail. It is estimated that 1.3 % of those who entered anaesthetic training during the interval were recognised to become chemically dependent during their training. Follow-up was available on only six of the 13 registrars and only one was reported to have completed training. The results of this survey indicate that chemical dependence is already a major health problem amongst anaesthetic registrars in Australia and New Zealand.
PubMed, Mar 1, 1994
Heart transplantation now provides an acceptable therapy for patients with severe end-stage heart... more Heart transplantation now provides an acceptable therapy for patients with severe end-stage heart disease. Although patient outcome has significantly improved both early and late after heart transplantation, early morbidity and mortality continues to affect overall survival and may be unpredictable. In an attempt to identify factors that may assist in predicting early outcome after orthotopic heart transplantation, we assessed allograft function in 16 patients in the immediate postoperative period, 30 minutes after weaning from cardiopulmonary bypass by measuring the fractional shortening of the left ventricle with transesophageal echocardiography. In addition, standard hemodynamic indexes of allograft function (arterial blood pressure, pulmonary capillary wedge pressure, mean pulmonary artery pressure, and cardiac output) were obtained at this early time point. Early outcome was assessed by the duration and peak dose of inotrope support required after transplantation, requirement for mechanical support, and the duration of stay in the intensive care unit. Left ventricular fractional shortening 30 minutes after cardiopulmonary bypass was significantly lower in those patients requiring inotropic support (28.4% +/- 4.6% versus 43.7% +/- 3.5%, p < 0.05), whereas hemodynamic variables failed to distinguish these groups. In those patients requiring inotropes, there was a significant negative correlation of fractional shortening with the peak dose (r = -0.87, p < 0.01) and the duration of inotropic support (r = -0.62, p < 0.05). The total ischemic time of the allograft (206 +/- 22 minutes, range 77 to 359) did not correlate with the subsequent fractional shortening, but patients requiring inotrope support after the operation had significantly longer ischemic times (259 +/- 22 versus 138 +/- 22 minutes, p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)
Anaesthesia and Intensive Care, Oct 1, 1997
There have been reports of a negative arterial to end-tidal CO 2 gradient (P a-ET CO 2) during ca... more There have been reports of a negative arterial to end-tidal CO 2 gradient (P a-ET CO 2) during cardiac surgery, so we used capnometry and an intravascular blood gas sensor (Paratrend 7) to continuously monitor this gradient in 20 cardiac surgical patients. We also compared the values obtained from this sensor with those obtained from a standard blood gas analyser at seven time points. We found a significant change in P a-ET CO 2 after cardopulmonary bypass (P<0.001) though we were unable to demonstrate a negative P a-ET CO 2 at any time (95% CI 0-14%). There was clinically acceptable agreement between laboratory and Paratrend 7 measurements during and after cardiac surgery.
![Research paper thumbnail of A Comparison of Epidural Ropivacaine Infusion Alone and in Combination with 1, 2, and 4 [micro sign]g/mL Fentanyl for Seventy-Two Hours of Postoperative Analgesia After Major Abdominal Surgery](https://attachments.academia-assets.com/113076947/thumbnails/1.jpg)
](Anesthesia & Analgesia, Apr 1, 1999
Anaesthesia & Intensive Care Medicine, Aug 1, 2021
Anaesthesia and Intensive Care, Dec 1, 1994
A randomized, controlled clinical trial was conducted on 72 patients undergoing elective cardiac ... more A randomized, controlled clinical trial was conducted on 72 patients undergoing elective cardiac surgery to compare patientcontrolled analgesia (PCA) to nurse-titrated infusion of morphine. Pain and nausea scores were assessed at 5, 20, 32 and 44 hours after cardiopulmonary bypass. Serum cortisol estimations were performed at 24 and 48 hours, and morphine consumption was measured at 0-24 and 24-48 hours. There was no difference between pain scores (P=0.72), nausea scores (P=0.52), serum cortisol at 24 and 48 hours (P=0.32 and P=0.34), and morphine consumption at 0-24 and 24-48 hours (P=0.16 and P=0.12). There was also no difference in the time to tracheal extubation (P= O. 79) and discharge from fCU (P= 0.64). There was a significant association between pain and serum cortisol at 48 hours (P= 0.023). This study also found a tenfold difference in the amount of morphine used (range = 11 to 108 mg), with no significant association with patient age or sex. We could find no significant benefit from the routine use of PCA in cardiac surgical patients.
Anaesthesia and Intensive Care, Jun 1, 1995
Cystic fibrosis is an autosomal recessive disorder which affects one in 2500 live births. It is a... more Cystic fibrosis is an autosomal recessive disorder which affects one in 2500 live births. It is a multisystem disease and has a variety of presentations. The major clinical features affect the gastrointestinal and respiratory tracts. Severe respiratory disease, diabetes and gastroesophageal reflux are common features of concern to anaesthetists. Improved care of young patients has allowed many to survive into adulthood. Lung transplantation has significantly improved the outlook for many patients. At Alfred Hospital, 74 patients with cystic fibrosis underwent 149 procedures from January 1978 to January 1994, with a mortality of 0.6% (95 % Cl 0.4 %-0.8%). This retrospective cohort study describes the anaesthetic management and perioperative care of these patients. Most of the anaesthetics were for procedures related to cystic fibrosis but 12% were for unrelated conditions. Cystic fibrosis related procedures include diagnostic, venous access, enteral feeding procedures, treatment of complications of cystic fibrosis and lung transplantation. Despite extremely poor respiratory function, these patients can be managed with acceptably low postoperative mortality (1%). Pre-and postoperative care must be directed towards optimal clearance of viscous respiratory secretions. Procedures need to be planned so that optimal care can be given by each member of the team caring for cystic fibrosis patients.
BJA: British Journal of Anaesthesia, May 1, 1996
We studied 151 patients undergoing total hip or knee arthroplasty, or cruciate ligament reconstru... more We studied 151 patients undergoing total hip or knee arthroplasty, or cruciate ligament reconstruction in a multicentre study in Australia and New Zealand. Patients were openly allocated randomly to one of five treatment groups or to a control group. General anaesthesia was induced after introduction of extradural block with 0.5 % ropivacaine. After surgery, patients received an extradural infusion of 0.2 % ropivacaine at 6, 8, 10, 12 or 14 ml h 91 or received no postoperative extradural infusion (control group). All patients had access to i.v. PCA morphine for supplementary analgesia. Morphine consumption was lower in all treatment groups compared with the control group, decreasing with increasing ropivacaine infusion rate. Median VAS scores were lower in all ropivacaine infusion groups compared with the control group for the first 10 h of the study; however by the end of the study, VAS scores were similar in all groups. The higher ropivacaine infusion rates caused a slower convergence of spread of the initial sensory block and a higher degree of motor block. The overall incidence of side effects was similar, with the exception of a higher incidence of urinary retention and hypotension in the groups receiving the higher rates of ropivacaine. The quality of treatment scores were similar for all treatment groups. (Br.
Heart, Lung and Circulation
Journal of Cardiac Failure, 2021
BACKGROUND There is a paucity of data on depression, anxiety and post-traumatic stress disorder (... more BACKGROUND There is a paucity of data on depression, anxiety and post-traumatic stress disorder (PTSD) after left ventricular assist device (LVAD) implantation. We designed an observational study to integrate these with functional capacity and health-related quality of life (HR-QOL) in surviving LVAD patients. METHODS Consenting patients between one month and 9 years post-LVAD implantation (n = 121) were screened for functional capacity (WHO Disability Assessment Schedule 2.0 [WHODAS 2.0)]); HR-QOL (European Quality of Life [EQ-5D] and Visual Assessment Scales [EQ-VAS]), depression (Patient Health Questionnaire [PHQ-9], anxiety (Generalized Anxiety Disorder Scale [GAD-7]) and PTSD (Impact of Event Scale Revised [IES-R]). RESULTS Of the 94% of patients who consented, 34.7% reported impaired functional capacity (WHODAS 2.0 score ≥ 25%), 23.1-34.7% HR-QOL problems (domain EQ-5D ≥ 3), 10.7% "poor health" (EQ-VAS ≤ 40), 14.9% depression (PHQ-9 > 14), 11.7% suicidal ideation and 17.5% anxiety (GAD-7 >10). 23.5% had a positive screen for PTSD (IES-R ≥ 24). EQ-VAS ≥ 80 predicted good functional capacity (p < 0.001). CONCLUSIONS A third of discharged LVAD patients reported impaired function, HR-QOL and psychological issues. Standardized evaluation before and after LVAD implantation could facilitate psychologic prehabilitation, inform decision-making and identify indications for mental health intervention.
The Journal of Heart and Lung Transplantation, 2020
The Journal of Heart and Lung Transplantation, 2020
The Journal of Heart and Lung Transplantation, 2018
IQR 21-45) vs 24hr (IQR 18-46), p= 0.20] and PGD. There were 2 deaths, one in each group. Conclus... more IQR 21-45) vs 24hr (IQR 18-46), p= 0.20] and PGD. There were 2 deaths, one in each group. Conclusion: A substantial proportion of usable donors will have a PF ratio < 300 measured in the ICU and the OR and function equally well as ≥ 300 donors without an increased risk of PGD or prolonged ventilation. The use of the 300 PF ratio threshold for acceptability of donor lungs results in wastage of donor lungs and unnecessary EVLP.
Anaesthesia and Intensive Care, 1999
Clonidine may have beneficial effects in patients undergoing major surgery. We enrolled 156 patie... more Clonidine may have beneficial effects in patients undergoing major surgery. We enrolled 156 patients having elective CABG surgery in a double-blind, randomized trial. Patients were randomized to receive either two doses of placebo (Group PP) or clonidine 5 μg/kg (Group CC). Perioperative measurements included haemodynamics, anaesthetic and analgesic drug usage, creatinine clearance, cortisol excretion, recovery times and quality of life (SF-36) after surgery. Overall, there was no significant difference with time to tracheal extubation (median [10–90 centile]): CC 7.1(3.4–18)h vs PP 8.0(4.3–17) h, P=0.70; but there was a higher proportion of patients extubated within four hours: CC 20% vs. PP 8%, P=0.038. Clonidine resulted in a number of significant (P<0.05) haemodynamic changes, particularly pre-CPB: less tachycardia and hypertension, more bradycardia and hypotension. Clonidine was associated with a significant (P<0.05) reduction in anaesthetic drug usage, higher creatinine ...
Anaesthesia and Intensive Care, 1996
We studied the relationship between oxygen delivery (DO2) and consumption (VO2) in twenty patient... more We studied the relationship between oxygen delivery (DO2) and consumption (VO2) in twenty patients undergoing cardiac surgery, in order to determine if VO2was dependent on DO2(pathological oxygen supply dependence). We measured VO2from expired gas analysis (VO2G) and compared this to that calculated using the reverse Fick method (VO2F). Both VO2Gand VO2Fincreased after cardiopulmonary bypass (P<0.001), without change in DO2(i.e. oxygen extraction ratio increased). There was a significant relationship between changes in DO2and VO2F, both before bypass (r=0.74, P < 0.001) and after bypass (r=0.69, P < 0.001), while changes in DO2and VO2Ghad no such relationship (pre-bypass: r=0.38, P=0.094; post-bypass: r=0.10, P=0.68). There was poor agreement between VO2Fand VO2Gperioperatively. We could not demonstrate supply dependence in elective cardiac surgical patients.
Anaesthesia and Intensive Care, 1993
The practice of cardiothoracic surgery and anaesthesia has become an area where technology has pr... more The practice of cardiothoracic surgery and anaesthesia has become an area where technology has progressed rapidly, and this is especially so in the field of cardiac transplantation. The concept of bridging patients with end stage dilated cardiomyopathy to transplant with mechanical ventricular assist devices (VADs) has moved from futuristic thought to practicality. In the area of intra-operative monitoring, two-dimensional transoesophageal echocardiography (TOE) presents a new noninvasive approach to moni
Anaesthesia and Intensive Care, 2004
CHEST Journal, 2013
ABSTRACT Respiratory Support PostersSESSION TYPE: Original Investigation PosterPRESENTED ON: Wedn... more ABSTRACT Respiratory Support PostersSESSION TYPE: Original Investigation PosterPRESENTED ON: Wednesday, October 30, 2013 at 01:30 PM - 02:30 PMPURPOSE: Intermittent positive airway pressure ventilation (IPPV) reduces right ventricular (RV) stroke volume in COPD. We aim to determine whether this reduction in RV stroke volume occurs via changes to RV preload and/or afterload.METHODS: Subjects with severe COPD receiving IPPV immediately prior to lung transplantation were prospectively assessed with pulmonary arterial catheterization. Changes to RV stroke volume (measured as the pulmonary pulse pressure change) were assessed at end-expiration, early-inspiration and end-inspiration. Changes to preload and afterload were assessed by inspiratory changes to right atrial pressure and diastolic pulmonary arterial pressure respectively. Data acquisition software enabled beat-by-beat, intra-breath hemodynamic assessment.RESULTS: Sixteen patients were recruited with median [IQR] age of 58 [51-61] yrs and post bronchodilator FEV1 of 0.57 [0.50-0.73] L. Patients were ventilated using IPPV with an inspiratory positive airway pressure of 20 [18.5-25] cm H2O, zero extrinsic positive end-expiratory pressure, respiratory rate of 6 breaths/min and fraction of inspired O2 of 60%. IPPV was associated with a reduced pulmonary pulse pressure from end-expiration to end-inspiration (3.6 [1.4-5.4] mm Hg, P=0.007). This reduction in pulmonary pulse pressure was associated with both an increase in RV afterload (spearman r (rs)=0.62, P=0.010) and a reduced RV preload (rs=0.57, P=0.022). Closer analysis reveals the reduction in pulmonary pulse pressure from end-expiration to early-inspiration was associated with an increase in RV afterload (rs=0.76, P=0.001) but not with reduced RV preload (rs=0.46, P=0.073). In contrast, the reduction in pulmonary pulse pressure from early-inspiration to end-inspiration was associated with a reduced RV preload (rs=0.56, P=0.024) but not with increased RV afterload (rs=0.26, P=0.327).CONCLUSIONS: Positive pressure ventilation reduces RV stroke volume which occurs predominantly in association with increased RV afterload during the early phase of inspiration and predominantly in association with reduced RV preload during the later phase of inspiration.CLINICAL IMPLICATIONS: Better understanding of heart-lung interactions will facilitate the development of improved ventilation strategies for COPD patients, especially for patients at risk of RV failure.DISCLOSURE: The following authors have nothing to disclose: Jeremy Wrobel, Bruce Thompson, Christopher Stuart-Andrews, Kirk Kee, Gregory Snell, Mark Buckland, Trevor WilliamsNo Product/Research Disclosure Information.
Anaesthesia & intensive care medicine/Anaesthesia and intensive care medicine, May 1, 2024
Anesthesia & Analgesia, Apr 1, 1999
Anaesthesia and Intensive Care, Apr 1, 1993
The Supervisors of Anaesthetic Training in Australia and New Zealand were surveyed and asked to r... more The Supervisors of Anaesthetic Training in Australia and New Zealand were surveyed and asked to report any cases of chemical dependence from anaesthetic registrars at their hospital from 1981 to 1991. From 83 questionnaires there were 65 (78%) returned There were 14 departments (22%) with experience of one or more cases during this interval. Only five (7%) reported conducting a lecture or tutorial on the problem. The departmental reports covered 4425 registrar years of training and there were 17 cases reported. Of these, 13 were complete and are considered in detail. It is estimated that 1.3 % of those who entered anaesthetic training during the interval were recognised to become chemically dependent during their training. Follow-up was available on only six of the 13 registrars and only one was reported to have completed training. The results of this survey indicate that chemical dependence is already a major health problem amongst anaesthetic registrars in Australia and New Zealand.
PubMed, Mar 1, 1994
Heart transplantation now provides an acceptable therapy for patients with severe end-stage heart... more Heart transplantation now provides an acceptable therapy for patients with severe end-stage heart disease. Although patient outcome has significantly improved both early and late after heart transplantation, early morbidity and mortality continues to affect overall survival and may be unpredictable. In an attempt to identify factors that may assist in predicting early outcome after orthotopic heart transplantation, we assessed allograft function in 16 patients in the immediate postoperative period, 30 minutes after weaning from cardiopulmonary bypass by measuring the fractional shortening of the left ventricle with transesophageal echocardiography. In addition, standard hemodynamic indexes of allograft function (arterial blood pressure, pulmonary capillary wedge pressure, mean pulmonary artery pressure, and cardiac output) were obtained at this early time point. Early outcome was assessed by the duration and peak dose of inotrope support required after transplantation, requirement for mechanical support, and the duration of stay in the intensive care unit. Left ventricular fractional shortening 30 minutes after cardiopulmonary bypass was significantly lower in those patients requiring inotropic support (28.4% +/- 4.6% versus 43.7% +/- 3.5%, p < 0.05), whereas hemodynamic variables failed to distinguish these groups. In those patients requiring inotropes, there was a significant negative correlation of fractional shortening with the peak dose (r = -0.87, p < 0.01) and the duration of inotropic support (r = -0.62, p < 0.05). The total ischemic time of the allograft (206 +/- 22 minutes, range 77 to 359) did not correlate with the subsequent fractional shortening, but patients requiring inotrope support after the operation had significantly longer ischemic times (259 +/- 22 versus 138 +/- 22 minutes, p < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)
Anaesthesia and Intensive Care, Oct 1, 1997
There have been reports of a negative arterial to end-tidal CO 2 gradient (P a-ET CO 2) during ca... more There have been reports of a negative arterial to end-tidal CO 2 gradient (P a-ET CO 2) during cardiac surgery, so we used capnometry and an intravascular blood gas sensor (Paratrend 7) to continuously monitor this gradient in 20 cardiac surgical patients. We also compared the values obtained from this sensor with those obtained from a standard blood gas analyser at seven time points. We found a significant change in P a-ET CO 2 after cardopulmonary bypass (P<0.001) though we were unable to demonstrate a negative P a-ET CO 2 at any time (95% CI 0-14%). There was clinically acceptable agreement between laboratory and Paratrend 7 measurements during and after cardiac surgery.
Anesthesia & Analgesia, Apr 1, 1999
Anaesthesia & Intensive Care Medicine, Aug 1, 2021
Anaesthesia and Intensive Care, Dec 1, 1994
A randomized, controlled clinical trial was conducted on 72 patients undergoing elective cardiac ... more A randomized, controlled clinical trial was conducted on 72 patients undergoing elective cardiac surgery to compare patientcontrolled analgesia (PCA) to nurse-titrated infusion of morphine. Pain and nausea scores were assessed at 5, 20, 32 and 44 hours after cardiopulmonary bypass. Serum cortisol estimations were performed at 24 and 48 hours, and morphine consumption was measured at 0-24 and 24-48 hours. There was no difference between pain scores (P=0.72), nausea scores (P=0.52), serum cortisol at 24 and 48 hours (P=0.32 and P=0.34), and morphine consumption at 0-24 and 24-48 hours (P=0.16 and P=0.12). There was also no difference in the time to tracheal extubation (P= O. 79) and discharge from fCU (P= 0.64). There was a significant association between pain and serum cortisol at 48 hours (P= 0.023). This study also found a tenfold difference in the amount of morphine used (range = 11 to 108 mg), with no significant association with patient age or sex. We could find no significant benefit from the routine use of PCA in cardiac surgical patients.
Anaesthesia and Intensive Care, Jun 1, 1995
Cystic fibrosis is an autosomal recessive disorder which affects one in 2500 live births. It is a... more Cystic fibrosis is an autosomal recessive disorder which affects one in 2500 live births. It is a multisystem disease and has a variety of presentations. The major clinical features affect the gastrointestinal and respiratory tracts. Severe respiratory disease, diabetes and gastroesophageal reflux are common features of concern to anaesthetists. Improved care of young patients has allowed many to survive into adulthood. Lung transplantation has significantly improved the outlook for many patients. At Alfred Hospital, 74 patients with cystic fibrosis underwent 149 procedures from January 1978 to January 1994, with a mortality of 0.6% (95 % Cl 0.4 %-0.8%). This retrospective cohort study describes the anaesthetic management and perioperative care of these patients. Most of the anaesthetics were for procedures related to cystic fibrosis but 12% were for unrelated conditions. Cystic fibrosis related procedures include diagnostic, venous access, enteral feeding procedures, treatment of complications of cystic fibrosis and lung transplantation. Despite extremely poor respiratory function, these patients can be managed with acceptably low postoperative mortality (1%). Pre-and postoperative care must be directed towards optimal clearance of viscous respiratory secretions. Procedures need to be planned so that optimal care can be given by each member of the team caring for cystic fibrosis patients.
BJA: British Journal of Anaesthesia, May 1, 1996
We studied 151 patients undergoing total hip or knee arthroplasty, or cruciate ligament reconstru... more We studied 151 patients undergoing total hip or knee arthroplasty, or cruciate ligament reconstruction in a multicentre study in Australia and New Zealand. Patients were openly allocated randomly to one of five treatment groups or to a control group. General anaesthesia was induced after introduction of extradural block with 0.5 % ropivacaine. After surgery, patients received an extradural infusion of 0.2 % ropivacaine at 6, 8, 10, 12 or 14 ml h 91 or received no postoperative extradural infusion (control group). All patients had access to i.v. PCA morphine for supplementary analgesia. Morphine consumption was lower in all treatment groups compared with the control group, decreasing with increasing ropivacaine infusion rate. Median VAS scores were lower in all ropivacaine infusion groups compared with the control group for the first 10 h of the study; however by the end of the study, VAS scores were similar in all groups. The higher ropivacaine infusion rates caused a slower convergence of spread of the initial sensory block and a higher degree of motor block. The overall incidence of side effects was similar, with the exception of a higher incidence of urinary retention and hypotension in the groups receiving the higher rates of ropivacaine. The quality of treatment scores were similar for all treatment groups. (Br.
Heart, Lung and Circulation
Journal of Cardiac Failure, 2021
BACKGROUND There is a paucity of data on depression, anxiety and post-traumatic stress disorder (... more BACKGROUND There is a paucity of data on depression, anxiety and post-traumatic stress disorder (PTSD) after left ventricular assist device (LVAD) implantation. We designed an observational study to integrate these with functional capacity and health-related quality of life (HR-QOL) in surviving LVAD patients. METHODS Consenting patients between one month and 9 years post-LVAD implantation (n = 121) were screened for functional capacity (WHO Disability Assessment Schedule 2.0 [WHODAS 2.0)]); HR-QOL (European Quality of Life [EQ-5D] and Visual Assessment Scales [EQ-VAS]), depression (Patient Health Questionnaire [PHQ-9], anxiety (Generalized Anxiety Disorder Scale [GAD-7]) and PTSD (Impact of Event Scale Revised [IES-R]). RESULTS Of the 94% of patients who consented, 34.7% reported impaired functional capacity (WHODAS 2.0 score ≥ 25%), 23.1-34.7% HR-QOL problems (domain EQ-5D ≥ 3), 10.7% "poor health" (EQ-VAS ≤ 40), 14.9% depression (PHQ-9 > 14), 11.7% suicidal ideation and 17.5% anxiety (GAD-7 >10). 23.5% had a positive screen for PTSD (IES-R ≥ 24). EQ-VAS ≥ 80 predicted good functional capacity (p < 0.001). CONCLUSIONS A third of discharged LVAD patients reported impaired function, HR-QOL and psychological issues. Standardized evaluation before and after LVAD implantation could facilitate psychologic prehabilitation, inform decision-making and identify indications for mental health intervention.
The Journal of Heart and Lung Transplantation, 2020
The Journal of Heart and Lung Transplantation, 2020
The Journal of Heart and Lung Transplantation, 2018
IQR 21-45) vs 24hr (IQR 18-46), p= 0.20] and PGD. There were 2 deaths, one in each group. Conclus... more IQR 21-45) vs 24hr (IQR 18-46), p= 0.20] and PGD. There were 2 deaths, one in each group. Conclusion: A substantial proportion of usable donors will have a PF ratio < 300 measured in the ICU and the OR and function equally well as ≥ 300 donors without an increased risk of PGD or prolonged ventilation. The use of the 300 PF ratio threshold for acceptability of donor lungs results in wastage of donor lungs and unnecessary EVLP.
Anaesthesia and Intensive Care, 1999
Clonidine may have beneficial effects in patients undergoing major surgery. We enrolled 156 patie... more Clonidine may have beneficial effects in patients undergoing major surgery. We enrolled 156 patients having elective CABG surgery in a double-blind, randomized trial. Patients were randomized to receive either two doses of placebo (Group PP) or clonidine 5 μg/kg (Group CC). Perioperative measurements included haemodynamics, anaesthetic and analgesic drug usage, creatinine clearance, cortisol excretion, recovery times and quality of life (SF-36) after surgery. Overall, there was no significant difference with time to tracheal extubation (median [10–90 centile]): CC 7.1(3.4–18)h vs PP 8.0(4.3–17) h, P=0.70; but there was a higher proportion of patients extubated within four hours: CC 20% vs. PP 8%, P=0.038. Clonidine resulted in a number of significant (P<0.05) haemodynamic changes, particularly pre-CPB: less tachycardia and hypertension, more bradycardia and hypotension. Clonidine was associated with a significant (P<0.05) reduction in anaesthetic drug usage, higher creatinine ...
Anaesthesia and Intensive Care, 1996
We studied the relationship between oxygen delivery (DO2) and consumption (VO2) in twenty patient... more We studied the relationship between oxygen delivery (DO2) and consumption (VO2) in twenty patients undergoing cardiac surgery, in order to determine if VO2was dependent on DO2(pathological oxygen supply dependence). We measured VO2from expired gas analysis (VO2G) and compared this to that calculated using the reverse Fick method (VO2F). Both VO2Gand VO2Fincreased after cardiopulmonary bypass (P<0.001), without change in DO2(i.e. oxygen extraction ratio increased). There was a significant relationship between changes in DO2and VO2F, both before bypass (r=0.74, P < 0.001) and after bypass (r=0.69, P < 0.001), while changes in DO2and VO2Ghad no such relationship (pre-bypass: r=0.38, P=0.094; post-bypass: r=0.10, P=0.68). There was poor agreement between VO2Fand VO2Gperioperatively. We could not demonstrate supply dependence in elective cardiac surgical patients.
Anaesthesia and Intensive Care, 1993
The practice of cardiothoracic surgery and anaesthesia has become an area where technology has pr... more The practice of cardiothoracic surgery and anaesthesia has become an area where technology has progressed rapidly, and this is especially so in the field of cardiac transplantation. The concept of bridging patients with end stage dilated cardiomyopathy to transplant with mechanical ventricular assist devices (VADs) has moved from futuristic thought to practicality. In the area of intra-operative monitoring, two-dimensional transoesophageal echocardiography (TOE) presents a new noninvasive approach to moni
Anaesthesia and Intensive Care, 2004
CHEST Journal, 2013
ABSTRACT Respiratory Support PostersSESSION TYPE: Original Investigation PosterPRESENTED ON: Wedn... more ABSTRACT Respiratory Support PostersSESSION TYPE: Original Investigation PosterPRESENTED ON: Wednesday, October 30, 2013 at 01:30 PM - 02:30 PMPURPOSE: Intermittent positive airway pressure ventilation (IPPV) reduces right ventricular (RV) stroke volume in COPD. We aim to determine whether this reduction in RV stroke volume occurs via changes to RV preload and/or afterload.METHODS: Subjects with severe COPD receiving IPPV immediately prior to lung transplantation were prospectively assessed with pulmonary arterial catheterization. Changes to RV stroke volume (measured as the pulmonary pulse pressure change) were assessed at end-expiration, early-inspiration and end-inspiration. Changes to preload and afterload were assessed by inspiratory changes to right atrial pressure and diastolic pulmonary arterial pressure respectively. Data acquisition software enabled beat-by-beat, intra-breath hemodynamic assessment.RESULTS: Sixteen patients were recruited with median [IQR] age of 58 [51-61] yrs and post bronchodilator FEV1 of 0.57 [0.50-0.73] L. Patients were ventilated using IPPV with an inspiratory positive airway pressure of 20 [18.5-25] cm H2O, zero extrinsic positive end-expiratory pressure, respiratory rate of 6 breaths/min and fraction of inspired O2 of 60%. IPPV was associated with a reduced pulmonary pulse pressure from end-expiration to end-inspiration (3.6 [1.4-5.4] mm Hg, P=0.007). This reduction in pulmonary pulse pressure was associated with both an increase in RV afterload (spearman r (rs)=0.62, P=0.010) and a reduced RV preload (rs=0.57, P=0.022). Closer analysis reveals the reduction in pulmonary pulse pressure from end-expiration to early-inspiration was associated with an increase in RV afterload (rs=0.76, P=0.001) but not with reduced RV preload (rs=0.46, P=0.073). In contrast, the reduction in pulmonary pulse pressure from early-inspiration to end-inspiration was associated with a reduced RV preload (rs=0.56, P=0.024) but not with increased RV afterload (rs=0.26, P=0.327).CONCLUSIONS: Positive pressure ventilation reduces RV stroke volume which occurs predominantly in association with increased RV afterload during the early phase of inspiration and predominantly in association with reduced RV preload during the later phase of inspiration.CLINICAL IMPLICATIONS: Better understanding of heart-lung interactions will facilitate the development of improved ventilation strategies for COPD patients, especially for patients at risk of RV failure.DISCLOSURE: The following authors have nothing to disclose: Jeremy Wrobel, Bruce Thompson, Christopher Stuart-Andrews, Kirk Kee, Gregory Snell, Mark Buckland, Trevor WilliamsNo Product/Research Disclosure Information.