PubMed Health⌕ Search

Biomedical subjects

D S Esmore

Publications and source records attributed to D S Esmore.

At least 19 recordsLinked to original sources
PubMed2000

Bilateral sequential single lung transplantation for pulmonary hypertension and Eisenmenger's syndrome.

BACKGROUND: Lung transplantation, with and without intracardiac repair for pulmonary hypertension (PH) and Eisenmenger's syndrome (EIS), has become an alternative transplant strategy to combined heart and lung transplantation (HLT). METHODS: Thirty-five patients with PH or EIS underwent either bilateral sequential single lung transplantation (BSSLT, group I, n = 13) or HLT (group II, n = 22). Another 74 patients, who underwent BSSLT for other indications, served as controls (group III). Immediate allograft function, early and medium-term outcomes, lung function, and 2-year survival were compared between the groups. RESULTS: Comparisons between groups I and II showed no significant difference in any variables except percent predicted forced vital capacity. Immediate allograft function was significantly inferior (p < 0.05) and the blood loss was greater (p < 0.01) in group I when compared with those in group III. However, this resulted in no significant difference in early and medium-term outcomes, and 2-year survival between the 2 groups. CONCLUSIONS: BSSLT for PH and EIS can be performed as an alternative procedure to HLT without an increase in early and medium-term morbidity and mortality. Results are comparable with BSSLT performed for other indications.

Adult↗
PubMed2000

Maximizing thoracic organ transplant opportunities: the importance of efficient coordination.

BACKGROUND: In Australia, despite large distances and one of the world's lowest multiorgan donor rates (11.4/million population/year), the thoracic organ transplant (TOTx) rate of 9.6/million population/year is one of the world's highest. METHODS: As an example of the Australian approach, a system of transplant coordination and organ allocation has evolved at the Alfred Hospital. Donor organs are assigned locally, or between the 4 major TOTx units on rotation. The recipient team then selects appropriate recipients, matching by blood group, size, cytomegalovirus (CMV) status, prospective cross matching and clinical status. An experienced recipient coordinator takes responsibility for organization of the retrieval and transplant process, including all operating room staff, all medical personnel, and transport for the donor team and the potential TOTx recipients. RESULTS: Between February 1989 and February 1999, 307 hearts, 48 heart/ lung, 124 single and 116 bilateral lung transplants were performed from 452 donor offers (52% beyond 500 miles). This represents 1.74 organs transplanted/thoracic donor and compares favourably to American United Network for Organ Sharing (1.43) and European (1.3) figures. CONCLUSIONS: The Australia TOTx model has enabled high transplant rates by efficiently using the available donor organs. This has been achieved through an enlarged, experience TOTx team, the optimizing of donor acceptance criteria and improving coordination logistics to allow multiple thoracic procedures simultaneously.

Australia↗
PubMed2000

Post-cardiac transplantation gout: incidence of therapeutic complications.

OBJECTIVE: To study the clinical impact of gout treatment following cardiac transplantation. METHODS: We performed an audit of all cardiac transplant recipients of the Alfred Hospital before August 1998 who lived in Victoria. RESULTS: We studied 225 patients (81% men), with a mean post-transplant follow-up of 50.8 months (SD 36). Forty-three (19%) had pre-transplant gout, 19 recurring post-transplantation. Twenty-three patients developed gout de novo. Of the 24 patients who received allopurinol, 6 developed pancytopenia and required hospitalization. Fourteen received a change in immunosuppression: in 5 patients following pancytopenia, and in 9 to enable safe use of allopurinol. Thirty-two patients received colchicine; 5 developed neuromyopathy. Impaired renal function, diuretic use, and hypertension were more common in this sub-group. Non-steroidal anti-inflammatory agents, used in 16 patients, caused serious complications in 1 patient (life-threatening peptic ulceration and hemorrhage, precipitating dialysis-dependent chronic renal failure). CONCLUSIONS: Cardiac transplant recipients, when treated for gout, are at high risk of therapeutic complications. Thus, gout treatment significantly affects care, health, and immunosuppression of these patients.

Adolescent↗
PubMed2000

Outcomes from paired single-lung transplants from the same donor.

BACKGROUND AND METHODS: Simultaneous, paired single-lung transplants from a single organ donor is one way to maximize lung transplant opportunities. Paired transplants allow comparison between left and right single-lung transplants and also provide insight into the relevance of donor vs recipient factors in rejection outcomes. RESULTS: Of 76 paired transplants (38 pairs) performed at the Alfred Hospital, 68 patients have survived >30 days. We observed no significant differences between left and right single-lung transplants in ICU stay (median, 3.1 vs 3.0 days; range, 0.5 to 83 vs 0.5 to 76 days), hospital stay (median, 19.5 vs 24.0 days; range, 1 to 118 vs 11 to 144 days), airway complications (5 vs 3), and 5-year survival (60% vs 50%). The 6 month, and 1- and 2-year survivals were lower in left single-lung transplant recipients, primarily related to increased mortality from airway complications. In 28 pairs, both recipients survived 90 days, and the incidence, frequency, and time of onset of acute rejection and chronic rejection (bronchiolitis obliterans syndrome [BOS]) were not significantly different. When sequentially performed lung transplants were separately analyzed, the incidence of acute rejection was not related to graft ischemic time. CONCLUSIONS: The general outcomes of right and left transplants are similar, although we observed increased 6-month to 2-year mortality associated with left lung transplantation. The lack of correlation between the incidence of acute rejection episodes or the severity of BOS in paired allograft recipients suggests that "donor factors" are not the dominant cause.

Adolescent↗
PubMed2000

A simplified method of harvesting and dilating the radial artery achieves acceptable clinical outcomes.

BACKGROUND: The recent successful revival of the radial artery as a coronary-bypass conduit has been attributed to a minimally traumatic harvesting technique without diathermy, combined with long-term oral calcium antagonist therapy. We describe a simplified technique of harvesting the radial artery, which reduces procurement time and maintains conduit relaxation. METHODS: Radial arteries were harvested using diathermy and topical glyceryl trinitrate-verapamil dilator solution. Postoperatively, intravenous glyceryl trinitrate, but no calcium antagonist was used. The clinical results in the first 100 consecutive patients receiving radial artery grafts (RA group), procured using this technique, were compared with a group of 100 patients receiving saphenous vein conduits (SV group) immediately prior to the introduction of the radial artery at our institution. RESULTS: There were no demographic differences between the two groups, other than the SV group being slightly older. There was one intraoperative death in each group. There was no difference in the rate of peri-operative myocardial infarction or length of stay in the intensive care unit. At a median follow-up time of 16 months for the RA group, and 25 months for the SV group, the survival rates were 97 and 94%, respectively. All survivors were in the New York Heart Association class I. In the SV group, two postoperative angioplasties were performed. CONCLUSIONS: These early results suggest that this method of procuring the radial artery using diathermy, glyceryl trinitrate and no postoperative calcium antagonists, is rapid, safe and effective. The continued use of this technique is justified, while awaiting the results of long-term angiographic studies.

Aged↗
PubMed2000

Outcomes of coronary artery bypass grafting: a 3 year analysis using the Society of Thoracic Surgeons Database.

BACKGROUND: Accurate risk factor analysis is a critical element in contemporary cardiac surgical practice. In the USA, the Society of Thoracic Surgeons Database allows institutions and individual surgeons to carry out detailed patient risk assessment and to review their cardiac surgical outcomes in a comparative fashion. METHODS: To evaluate outcomes of isolated coronary artery bypass grafting, data from all patients operated upon at the Alfred Hospital, Melbourne, Australia, over a 3 year period were entered into the Society of Thoracic Surgeons Database. RESULTS: Our results (mortality and morbidity) compared favourably with those contained within this large international database. CONCLUSION: It is hoped that a similar Australasian database can be established to facilitate a meaningful local risk assessment and a comparative analysis of outcomes of cardiac surgical procedures.

Journal Article↗
PubMed1999

Impact of graft ischemic time on outcomes after bilateral sequential single-lung transplantation.

BACKGROUND: Graft ischemic time (GIT) is a potential limiting factor in lung transplantation. METHODS: Seventy-four patients who underwent bilateral sequential single-lung transplantation were divided into three groups: group I, GIT less than 5 hours (n = 20); group II, GIT between 5 and 8 hours (n = 39); and group III, GIT more than 8 hours (n = 15). We compared early allograft function (ratio of arterial oxygen tension to inspired oxygen fraction and alveolar-arterial oxygen gradient), blood loss, the need for tracheostomy, the duration of ventilation, intensive care unit stay, and hospital stay. We also compared prevalences of acute and chronic rejection, airway complications, lung function test, and 2-year survival. RESULTS: Early allograft function in group III was significantly worse than those in groups I and II. However, there was no significant difference in any other variables of early and medium-term outcomes among the three groups. No significant correlation was detected between GIT and duration of intensive care unit stay or hospital stay. CONCLUSIONS: The limitation of acceptable GIT could be extended from the traditionally approved 4 to 5 hours, to 5 to 8 hours or even longer.

Adult↗
PubMed1999

Increased temperature reduces the protective effect of University of Wisconsin solution in the heart.

BACKGROUND: The protective effect of University of Wisconsin solution (UW) for hypothermic storage of donor hearts has been demonstrated in the laboratory. However, clinical usage is associated with occasional primary graft failures. We postulated that this could be related to adverse effects of UW on the coronary vasculature during cardiac implantation and rewarming. We therefore assessed recovery of contractile function and coronary flow in rat hearts after cardioplegic arrest using UW compared with St. Thomas' solution (ST) at 4 degrees C or 25 degrees C. METHODS: Cardioplegia was induced in isolated rat hearts using either UW or ST at 4 degrees C. Hearts were then maintained at 4 degrees C or 25 degrees C. In some hearts, UW at 4 degrees C was used for inducing arrest followed by flushing with ST at 4 degrees C and then rewarming to 25 degrees C. After 40 minutes of arrest, recovery of function and coronary flow were measured. Nuclear track emulsion was used to assess microvascular competence. RESULTS: Compared with ST-treated hearts, UW-treated hearts showed significant reduction in recovery of function at 25 degrees C (76.2% +/- 4.0% versus 25.0% +/- 4.1%; p < 0.01) but not at 4 degrees C (88.0% +/- 1.6% versus 87.1% +/- 2.6%). Recovery of coronary flow in the UW-treated hearts at 25 degrees C was significantly lower than that in the ST-treated hearts at 25 degrees C (71.7% +/- 3.0% versus 94.5% +/- 6.3%; p < 0.01). At 25 degrees C, microvascular competence was reduced in the UW group compared with the ST group. At 25 degrees C, flushing out UW with ST resulted in greater recovery of function compared with UW throughout (73.4% +/- 7.1% versus 25.0% +/- 4.1%; p < 0.01). CONCLUSIONS: University of Wisconsin solution provides effective donor heart protection under hypothermic conditions but can be deleterious at warmer temperatures.

Adenosine↗
PubMed1999

Maximizing the utilization of donor organs offered for lung transplantation.

The number of patients awaiting lung transplantation (LT) and waiting time for surgery is increasing. In Australia, LT rates are 4. 6/million population/yr, which despite low organ donation rates, are the highest published in the world. The Australian organ allocation system allows identification of marginal donors and therapeutic manipulation where appropriate. This study aims to assess the impact of utilization of marginal donors and aggressive donor management. A comparison between published donor criteria and local practice is made, allowing assessment of the effect of using marginal donors on outcome. Donor management included antibiotic therapy, strict fluid management, physiotherapy, bronchoscopy and bronchial toilet, and alteration of ventilatory settings including initiation of pressure support. Blood gases were repeated to assess the results of interventions. Between January 1, 1995 and May 31, 1998, we performed 140 transplants from 112 of 219 (51%) lung donor offers. Of these donors, 48 (43%) satisfied all published criteria for suitable donor organs (Group 1 = ideal donors) and 64 (57%) did not (Group 2 = marginal donors). Criteria breached by the marginal donors were: an initial ratio of arterial oxygen pressure to fraction of inspired oxygen (PaO2/FIO2) < 300 mm Hg (n = 20), abnormal radiology (n = 39), pulmonary infection (n = 24), 20 pack-years smoking (n = 5) and age > 55 yr (n = 4). Therapeutic manipulation resulted in improvement in the PaO2/FIO2 ratio in 20 donors (Group 3) who would not otherwise have been used. Immediate and 24 h postoperative gas exchange and length of intensive care unit (ICU) stay was not different for recipients from donors from all three groups. Overall survival was 94% at 30 d, 83% at 1 yr, 70% at 2 yr, and 62% at 3 yr and was not significantly different from the three groups. We conclude that organ utilization can be maximized by therapeutic manipulation and utilization of marginal donors without compromising results from transplantation.

Adult↗
PubMed1999

Clonidine and cardiac surgery: haemodynamic and metabolic effects, myocardial ischaemia and recovery.

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 micrograms/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 clearance, lower cortisol excretion and improvement in some aspects of quality of life. This study lends support to consideration of clonidine therapy in patients undergoing CABG surgery.

Adrenergic alpha-Agonists↗
PubMed1999

Coronary artery disease in potential lung transplant recipients > 50 years old: the role of coronary intervention.

STUDY OBJECTIVES: To review the experience of the Alfred Hospital in the systematic assessment of coronary artery disease (CAD) using coronary angiography (CA), and the subsequent management of CAD, in potential lung transplant recipients. DESIGN: Retrospective study. SETTING: The Alfred Hospital Lung and Heart Transplant Service. PATIENTS: CAD risk factors were sought in potential recipients of lung transplantation (LTx) who were > 50 years old, including a history of smoking, male gender, hypertension, diabetes, hypercholesterolemia, angina, and a family history of CAD. When feasible, and in the presence of more than one cardiac risk factor, CA was performed. RESULTS: From 243 referral patients who were > 50 years old, 97 were listed for LTx, and 77 underwent LTx. Four patients were refused LTx on the basis of CAD. Of 101 patients undergoing a detailed cardiac assessment for LTx, 83 had smoked, 56 were male, 48 had hypercholesterolemia, 22 had hypertension, 4 had diabetes, and 3 had a history consistent with angina. Eighty-five patients underwent CA. In 32 cases, CA revealed CAD, and half of these cases were significant stenoses. Eight patients who were assessed required intervention. Five patients of this group have been transplanted; of these, three patients underwent coronary artery grafting at the time of LTx, and two patients underwent preoperative angioplasty or stenting. Only one of these five patients died < 90 days postoperatively. CONCLUSION: Significant CAD is a common finding in older patients who are presenting for LTx. Coronary revascularization for severe large vessel stenoses can allow safe LTx. CAD risk factors may predict who should undergo CA, but further studies of clinical and noninvasive assessments of CAD are needed if CA is to be safely avoided in patients at low risk of CAD.

Combined Modality Therapy↗
PubMed1998

The limited role of myocardial fluorine-18 fluorodeoxyglucose imaging in candidates for cardiac transplantation: a planar imaging study.

This study compares the incidence and extent of hibernating myocardium (defined by myocardial perfusion/metabolism mismatch) in 28 cardiac transplant candidates with ischaemic cardiomyopathy and in 16 other patients with coronary artery disease (CAD) undergoing viability assessment. It then reviews the impact of myocardial perfusion metabolism imaging on management decisions in the transplant candidates at 6 months after scintigraphy. Each patient underwent a planar myocardial thallium-201 and fluorine-18 fluorodeoxyglucose scan on a modified gamma camera. Perfusion/metabolism mismatch was sized semi-quantitatively and each patient was assigned a global mismatch score. Transplant candidates had a lower left ventricular ejection fraction (LVEF) (P < 0.0002) and extent of hibernation myocardium (lower global mismatch score: P = 0.005) than other CAD patients but the difference in respect of mismatch frequency (8/28 vs 9/16 patients) did not reach statistical significance. Transplant candidates with LVEF < 20% had a lower global mismatch score (P < 0.02) than those with an LVEF > or = 20%. Interestingly two of three other CAD patients with LVEF < 20% had a moderate mismatch. Follow-up studies revealed the lack of impact of metabolic imaging as none of the three transplant candidates who eventually underwent revascularisation had hibernating myocardium and transplantation was offered to one of only two candidates with more than one minor mismatch. Thus metabolic imaging in potential transplant candidates may be of limited value because of the very low extent of hibernating myocardium, particularly if LVEF is below 20% and where clinical decisions are often based on many other factors.

Adult↗
PubMed1997

Lung volume reduction surgery for emphysema.

OBJECTIVE: To report the results of lung volume reduction surgery (LVRS) for severe emphysema in Australia. SETTING: A tertiary teaching hospital. DESIGN: A prospective study of a consecutive case series. PARTICIPANTS: 20 patients (mean age, 56 years) with severe emphysema--mean forced expiratory volume in one second (FEV1), 0.72 L (28% of predicted) and severe gas trapping (mean residual volume, 286% of predicted). INTERVENTION: Bilateral apical LVRS was performed via a median sternotomy with a linear stapler; bovine pericardial strips were used to reinforce the staple line. RESULTS: There was a 95% survival, and a mean (range) inpatient stay of 17 (8-45) days. No complications occurred in nine patients; a further six patients had only minor complications. Five patients had major complications (sputum retention requiring reintubation, persistent air leak requiring reoperation, duodenal perforation, and epidural haemorrhage); one patient died from multiorgan failure at 28 days. Intercostal drainage was left in situ for a mean of eight days. The results of FEV1, Medical Research Council (MRC) Dyspnoea Score and six-minute walk test improved in more than 90% of patients. FEV1 improved an average of 0.35 L (54% over baseline) (P < 0.001). Mean MRC Dyspnoea Score decreased from 3.4 to 2.1 (P < 0.001). Mean distance for the six-minute walk test increased from 306 to 431 metres (P < 0.001). CONCLUSION: Our experience confirms that LVRS produces worthwhile early outcomes for a subgroup of patients with severe emphysema. The clinical, economic and ethical questions raised by this new therapy will need to be assessed.

Adult↗
PubMed1997

Early hemodynamic effects of left atrial administration of epinephrine after cardiac transplantation.

We studied the hemodynamic effects of left atrial (LA) administration of epinephrine in 10 patients after cardiac transplantation, using a prospective, randomized, double-blind, cross-over design. After allograft implantation, a LA catheter was inserted and epinephrine infusion commenced at 100 ng.kg-1.min-1. Each trial period consisted of 20 min, with the LA and right atrial (RA) lines switched over between each period; hemodynamic measurements were taken after each time period. Whether epinephrine was administered via the RA or LA did not significantly alter hemodynamics (RA versus LA): mean (SD) arterial blood pressure 67 (7.5) vs 64 (9.5) mm Hg (P = 0.16), mean pulmonary artery pressure 22 (4.0) vs 21 (9.4) mm Hg (P = 0.67), cardiac index 3.2 (1.1) vs 3.2 (1.1) L.min-1.m-2 (P = 0.83), pulmonary vascular resistance index 308 (157) vs 345 (157) dynes.s.cm-5/m-2 (P = 0.30) or right ventricular ejection fraction 35% (11%) vs 32% (9.8%) (P = 0.23). Arterial epinephrine plasma levels were similar (P = 0.16). There was no significant pulmonary extraction of measured catecholamines. We observed no hemodynamic benefit of LA epinephrine administration. It may be that the cardiac transplantation population reacts differently compared with other cardiac surgical patients (possibly because pulmonary extraction of catecholamines is reduced). Because we did not observe a hemodynamic advantage in patients immediately after cardiac transplantation, we would not recommend the use of LA epinephrine at the dose studied.

Adult↗
PubMed1997

Quantitative detection of human cytomegalovirus DNA in lung transplant recipients.

Human cytomegalovirus (HCMV) disease remains a major cause of morbidity and mortality after lung transplantation. Currently, routine diagnostic tests for HCMV are inefficient and insensitive or nonspecific for HCMV disease. We describe an efficient, highly sensitive, quantitative polymerase chain reaction (PCR) assay for HCMV using competitive PCR and fluorescently labeled primers, and we have used this to measure HCMV DNA load in donor and recipient tissues of six lung transplant recipients at the time of transplantation, and 2 wk after transplantation when clinically stable. Total DNA yield was adequate for analysis in transbronchial biopsy, bronchoalveolar lavage, and peripheral blood leukocytes, but the endobronchial biopsy specimens did not consistently produce sufficient DNA for analysis. There was a large intersubject and intrasubject variability between tissues in HCMV DNA load, with a tendency for greater levels in lung tissue compared with BAL or peripheral blood cells. All six HCMV IgG seronegative donors or recipients were found to have HCMV DNA present. One of the three seronegative matched transplant recipients developed histopathologically proven HCMV disease, and HCMV DNA levels were shown to increase at that time point and subsequently decrease with ganciclovir treatment. This assay will allow prospective studies to confirm the predictive value of HCMV DNA load in donor and recipient tissues for HCMV disease.

Antibodies, Viral↗
PubMed1996

Improved sternal fixation in the transsternal bilateral thoracotomy incision.

The success of bilateral sequential single-lung transplantation has led to the rebirth of the transsternal bilateral thoracotomy incision. Despite the multiple advantages of this incision over a median sternotomy for this operation, one distinct disadvantage is the high prevalence of sternal disruption at the transverse sternotomy site, which is traditionally closed with sternal wires. This disruption rate is between 20% and 40% in most institutions and can lead to significant pain and deformity in addition to slowing the postoperative recovery and increasing the risk of sternal infection. To overcome this problem we have designed and manufactured a device that provides a sound method of fixating the sternum. The device is composed of two plates, one anterior and one posterior to the sternum, that are fixed to each other and to the sternum by means of screws into internally threaded posts positioned in predrilled holes through the bone on either side of the sternotomy. All components of the device are made from titanium and a range of post lengths are available to accommodate variability in sternal thickness. The structure of the device is demonstrated. The device has now been inserted into a total of 20 patients after bilateral lung transplantation and the preliminary results suggest this is a superior technique for closure of a transverse sternotomy and support continued and routine use.

Bone Wires↗