Biomedical subjects

S Tobe

Publications and source records attributed to S Tobe.

At least 19 recordsLinked to original sources

PubMed2001

Angiosarcoma causing cardiac rupture.

We report the 7th known case in the literature of cardiac angiosarcoma resulting in cardiac rupture. A 34-year-old woman was admitted presenting chest pain and pericardial effusion. After the patient had been treated for 3 months under the diagnosis of pericarditis of unknown etiology, she became hypotensive. Doppler echocardiography showed increased pericardial effusion and a communication between the right atrium and the pericardial cavity. An emergency operation was undertaken to drain the effusion and explore the etiology. We found the ruptured right atrium and the irregularly shaped tumor extending from the pericardium near the inferior caval vein to the right ventricle. There was no apparent tumor on the right atrium, but its wall was extensively thin, which we replaced with autologous pericardium. The patient died on the 44th postoperative day. Clinical diagnosis of cardiac angiosarcoma is usually very difficult. If Doppler echocardiography demonstrates pericardial effusion and find a ruptured right atrium with or without mass formation, we should suspect cardiac angiosarcoma.

Adult↗

PubMed2001

What is the optimal strategy to intensify blood pressure control and prevent progression of renal failure?

Recent clinical trials clearly demonstrate that patients with diabetes and hypertension, and patients with renal disease and hypertension, should have their blood pressure lowered intensively. A recent analysis of long-term clinical trials over the past 8 years clearly demonstrates that the lower the blood pressure over a range of values, the greater the preservation of renal function. It is also readily apparent that monotherapy does not suffice in attaining these more intensified goals. A review of five clinical trials in the recent National Kidney Foundation consensus report demonstrates that patients randomized to the lower level of blood pressure required an average of 3.2 different antihypertensive medications taken daily. Consequently, it is evident that the question is no longer what the initial preferred monotherapy should be, but rather what should be the optimal drug to add to an angiotensin converting enzyme inhibitor or angiotensin receptor blocker. In this paper we review data from several recent studies clearly indicating that to achieve goal blood pressure in the clinical setting of metabolic disarray and hyperglycemia, long-acting calcium antagonists constitute an excellent add-on agent for enhancing efficacy. We anticipate that the data that will accrue from the IDNT and RENAAL studies will further delineate the renal effects of dihydropyridine calcium antagonists.

Antihypertensive Agents↗

PubMed2001

Cardiovascular disease in patients with chronic kidney disease: getting to the heart of the matter.

The high prevalence of cardiovascular disease (CVD) in patients with kidney disease is well described. This Canadian, multicenter, observational cohort study reports the prevalence and risk factors of CVD associated with kidney disease, in a cohort of patients with established chronic kidney disease (CKD), who are followed-up by nephrologists. This analysis sought to answer 2 questions: (1) in patients with established CKD, are the prevalence and progression of CVD accounted for by conventional or uremia-related risk factors, and (2) to what extent can progression to renal replacement therapy (RRT) be explained by CVD versus traditional risk factors for kidney disease? This study population consists of 313 patients (predominantly men) who had a mean age of 56 years and a mean creatinine clearance of 36 mL/min. Thirty percent were diabetic. The overall prevalence of CVD was 46%, and was independent of severity of kidney dysfunction (P = 0.700). The median follow-up time was 23 months, for a total of 462 patient years. We note the overall incidence of CVD events (new CVD or worsening of CVD) was 47/244 (20%). The best predictors of new CVD events among those without preexisting CVD were diabetes (odds ratio [OR] = 5.35, P = 0.018) and age (OR = 1.26, P = 0.08). In those with preexisting CVD, low diastolic pressure (DP) (OR =.72, P = 0.004) and high triglycerides (OR = 1.48, P = 0.019) at baseline were independent predictors of progression of CVD. We could not determine an independent impact of kidney function on CVD in the overall cohort. Furthermore, we determined that the presence of CVD itself confers an increased risk for progression to RRT (relative risk [RR] = 1.58, P = 0.047), adjusted for kidney function. This is the first in-depth analysis of CVD in a cohort of patients with established chronic kidney disease who are not on dialysis. The question regarding the impact of the altered biology of uremia in contributing to CVD progression remains unanswered, and clearly needs further study. However, the findings do raise the issue of whether aggressive treatment of CVD and risk factors might, in fact, reduce progression to RRT. Further large-scale, observational studies as well as interventional studies are needed to more clearly understand the complex biology of cardiovascular and kidney disease progression.

Age Distribution↗

PubMed2001

The 2000 Canadian recommendations for the management of hypertension: Part one--therapy.

OBJECTIVE: To provide updated, evidence-based recommendations for the therapy of hypertension in adults. OPTIONS: For patients with hypertension, there are a number of lifestyle manoeuvres and antihypertensive agents that may control blood pressure. Randomized trials evaluating first- line therapy with thiazides, beta-adrenergic antagonists, angiotensin-converting enzyme inhibitors, calcium channel blockers, alpha-blockers, centrally acting agents or angiotensin II receptor antagonists were reviewed. OUTCOMES: The health outcomes considered were changes in blood pressure, cardiovascular morbidity, and cardiovascular and/or all-cause mortality rates. Economic outcomes were not considered due to insufficient evidence. EVIDENCE: Medline searches were conducted from the period of the last revision of the Canadian Recommendations for the Management of Hypertension (May 1998 to October 2000). Reference lists were scanned, experts were polled, and the personal files of the subgroup members and authors were used to identify other studies. All relevant articles were reviewed and appraised, using prespecified levels of evidence, by content experts and methodological experts. VALUES: A high value was placed on the avoidance of cardiovascular morbidity and mortality. BENEFITS, HARMS, AND COSTS: Various lifestyle manoeuvres and antihypertensive agents reduce the blood pressure of patients with sustained hypertension. In certain settings, and for specific classes of drugs, blood pressure lowering has been associated with reduced cardiovascular morbidity and/or mortality. RECOMMENDATIONS: The present document contains detailed recommendations pertaining to all aspects of the therapy of patients with hypertension, including lifestyle modifications proven to lower blood pressure, treatment thresholds, target blood pressures, choice of agents in various settings and strategies to enhance adherence. Lower thresholds for blood pressure treatment are advocated for people with other cardiovascular risk factors or established hypertensive target organ damage. Implicit in the recommendations for therapy is the principle that treatment should be individualized for each patient and the choice of agent should be dictated by coexistent conditions. For the treatment of uncomplicated essential hypertension, thiazides, beta-adrenergic antagonists, angiotensin-converting enzyme inhibitors or calcium channel blockers may be appropriate, depending on individual circumstances. VALIDATION: All recommendations were graded according to strength of the evidence and voted on by the Canadian Hypertension Recommendations Working Group. Only those recommendations achieving high levels of consensus are reported here. These guidelines will be updated annually.

Adult↗

PubMed2001

Renal dysfunction after cardiac surgery.

OBJECTIVE: To assess the causes and outcomes of patients with postcardiac surgery renal dysfunction. PATIENTS AND METHODS: A large cardiovascular data- base including pre-, peri- and postoperative serum creatinine concentrations from 2214 consecutive cardiac surgery patients was analyzed. RESULTS: Sixty-nine patients developed postoperative renal dysfunction, defined as at least a 15 mL/min decline in the creatinine clearance rate resulting in a value of less than 40 mL/min. These patients were significantly older, and had a higher incidence of previous cardiac surgery, diabetes, obesity, peripheral vascular disease, hypertension and poor ventricular function. Postoperatively, these patients had a higher occurrence of low output syndrome and myocardial infarction. Stepwise logistic regression predictors of postoperative renal dysfunction included the following: postoperative low output syndrome; repeat cardiac surgery; being older than 65 years; having diabetes; having poor left ventricular function; and having had valve surgery. Preoperative renal dysfunction (defined as a creatinine clearance of less than 40 mL/min) was not found to be one of the predictors. The mean creatinine concentrations of patients with mild postoperative renal dysfunction (defined as a creatinine concentration of less than 200 mmol/L on the fourth or fifth postoperative day) decreased significantly at the fifth postoperative day, while that of patients with severe postoperative renal dysfunction rose to a mean of 300 mmol/L six months postoperatively. The incidence of late dialysis (defined as a need for dialysis after postoperative day 10) approached 30% among patients with severe postoperative renal dysfunction and only 2% among patients with mild postoperative renal dysfunction. The early mortality rate (during the first postoperative month) was similar in both groups and approached 30%. CONCLUSIONS: Patients who develop postoperative renal dysfunction have a high mortality rate. Postoperative low cardiac output is the most important cause of postoperative renal dysfunction and, therefore, should be avoided. Patients with creatinine concentrations of less than 200 mmol/L at postoperative day 4 or 5 will probably resume normal renal function. Patients with creatinine concentrations of more than 200 mmol/L at days 4 and 5 have a 30% chance of needing long term dialysis.

Age Distribution↗

PubMed2001

The 2000 Canadian recommendations for the management of hypertension: part two--diagnosis and assessment of people with high blood pressure.

OBJECTIVE: To provide updated, evidence-based recommendations for the diagnosis and assessment of high blood pressure in adults. OPTIONS: For people with high blood pressure, the assignment of a diagnosis of hypertension depends on the appropriate measurement of blood pressure, the level of the blood pressure elevation, the duration of follow-up and the presence of concomitant vascular risk factors, target organ damage and established atherosclerotic diseases. For people diagnosed with hypertension, defining the overall risk of adverse cardiovascular outcomes requires laboratory testing, a search for target organ damage and an assessment of the modifiable causes of hypertension. Out-of-clinic blood pressure assessment and echocardiography are options for selected patients. OUTCOMES: People at increased risk of adverse cardiovascular outcomes and were identified and quantified. EVIDENCE: Medline searches were conducted from the period of the last revision of the Canadian recommendations for the management of hypertension (May 1998 to October 2000). Reference lists were scanned, experts were polled, and the personal files of the subgroup members and authors were used to identify other studies. All relevant articles were reviewed and appraised, using prespecified levels of evidence, by content experts and methodological experts. VALUES: A high value was placed on the identification of people at increased risk of cardiovascular morbidity and mortality. BENEFITS, HARMS AND COSTS: The identification of people at higher risk of cardiovascular disease will permit counselling for lifestyle manoeuvres and the introduction of antihypertensive drugs to reduce blood pressure for patients with sustained hypertension. In certain settings, and for specific classes of drugs, blood pressure lowering has been associated with reduced cardiovascular morbidity and/or mortality. RECOMMENDATIONS: The present document contains detailed recommendations pertaining to aspects of the diagnosis and assessment of patients with hypertension, including the accurate measurement of blood pressure, criteria for the diagnosis of hypertension and recommendations for follow-up, routine and optional laboratory testing, assessment for renovascular hypertension, home and ambulatory blood pressure monitoring, and the role of echocardiography in hypertension. VALIDATION: All recommendations were graded according to strength of the evidence and voted on by the Canadian Hypertension Recommendations Working Group. Only the recommendations achieving high levels of consensus are reported here. These guidelines will be updated annually. ENDORSEMENT: These recommendations are endorsed by the Canadian Hypertension Society, The Canadian Coalition for High Blood Pressure Prevention and Control, The College of Family Physicians of Canada, The Heart and Stroke Foundation of Canada, The Adult Disease Division and Bureau of Cardio-Respiratory Diseases and Diabetes at the Centre for Chronic Disease Prevention and Control of Health Canada.

Adrenal Gland Neoplasms↗

PubMed2000

Anger expression, gender, and ambulatory blood pressure in mild, unmedicated adults with hypertension.

The suppression of anger has been associated with the development of hypertension. This study evaluated the association between anger management style (anger-in and anger-out) and ambulatory blood pressure (ABP) in patients with repeated clinic diastolic blood pressures (DBPs) between 90-105 mmHg, unmedicated and with no known coronary artery disease. A total of 128 men (46.0 years) and 66 women (46.6 years) participated. Fourteen percent of men and 35% of women were classified as having "white coat" hypertension (daytime DBP < 85 mmHg). Mean awake and sleep DBP and systolic blood pressure (SBP) were evaluated in a repeated measures analysis of variance (ANOVA). Anger-in and anger-out scores were categorized into low, medium, and high t-scores (< 50, 50-59, > or = 60). Results indicated that in women, increasing anger-in is associated with greater SBPs while awake and sleeping, whereas no effect was found for DBP, nor any effect in men. No significant association was found between gender, anger-out, and ABP. The clinical diagnostic status of white coat hypertension was not differentially associated with anger-in or anger-out in men and women. In conclusion, in a sample of mild unmedicated adults with hypertension, suppression of anger is associated with greater ambulatory SBP in women, but not in men.

Adult↗

PubMed2000

Perfusatory recovery of the grafted lung during convalescence from acute rejection.

The aim of this study was to evaluate whether or not perfusatory recovery of the grafted lung occurs is the early stage of convalesce from acute rejection following a single lung transplantation. Eight adult mongrel dogs underwent an allotransplantation of the left lung with treatment of 10 mg/kg cyclosporine and 4 mg/kg azathioprine. Doppler flow probes were placed to the ascending aorta and the left pulmonary artery. Immunosuppressant therapy was discontinued to induce rejection after postoperative day 14. When the left pulmonary artery flow rate (l-PAFR) decreased to less than 20%, methylprednisolone (20 mg/kg) was administered for 3 days along with a resumption of cyclosporine and azathioprine. Pulmonary circulation and chest roentgenograms were evaluated every day through the rejection episode. An open lung biopsy was also performed in each dog to obtain specimens of the grafts and native lungs for histologic examination. When l-PAFR decreased to less than 20%, mild acute rejection was found in all dogs. l-PAFR increased significantly on the third day after methylprednisolone treatment. Thereafter, a histologic examination revealed minimal acute rejection in one dog and no abnormality in seven dogs. The perfusatory recovery of the grafted lung was thought to reflect the histological change in the course of convalescence.

Acute Disease↗

PubMed1999

Left ventricular mass index increase in early renal disease: impact of decline in hemoglobin.

Cardiovascular disease occurs in patients with progressive renal disease both before and after the initiation of dialysis. Left ventricular hypertrophy (LVH) is an independent predictor of morbidity and mortality in dialysis populations and is common in the renal insufficiency population. LVH is associated with numerous modifiable risk factors, but little is known about LV growth (LVG) in mild-to-moderate renal insufficiency. This prospective multicenter Canadian cohort study identifies factors associated with LVG, measured using two-dimensional-targeted M-mode echocardiography. Eight centers enrolled 446 patients, 318 of whom had protocol-mandated clinical, laboratory, and echocardiographic measurements recorded. We report 246 patients with assessable echocardiograms at both baseline and 12 months with an overall prevalence of LVH of 36%. LV mass index (LVMI) increased significantly (>20% of baseline or >20 g/m2) from baseline to 12 months in 25% of the population. Other than baseline LVMI, no differences in baseline variables were noted between patients with and without LVG. However, there were significant differences in decline of Hgb level (-0.854 v -0.108 g/dL; P = 0.0001) and change in systolic blood pressure (+6.50 v -1.09 mm Hg; P = 0.03) between the groups with and without LVG. Multivariate analysis showed the independent contribution of decrease in Hgb level (odds ratio [OR], 1.32 for each 0.5-g/dL decrease; P = 0.004), increase in systolic blood pressure (OR, 1.11 for each 5-mm Hg increase; P = 0.01), and lower baseline LVMI (OR, 0.85 for each 10-g/m2; P = 0.011) in predicting LVG. Thus, after adjusting for baseline LVMI, Hgb level and systolic blood pressure remain independently important predictors of LVG. We defined the important modifiable risk factors. There remains a critical need to establish optimal therapeutic strategies and targets to improve clinical outcomes.

Anemia↗

PubMed1999

Marital cohesion and ambulatory blood pressure in early hypertension.

One hundred thirty-four men and seventy-one women, unmedicated mild hypertensives, underwent 24-h ambulatory blood pressure (BP) monitoring (ABP) and completed standardized questionnaires measuring marital and job stress. Of these, 44.8% had daytime diastolic BP < 90 mm Hg; 96.1% had left ventricular mass index in the normal range (N = 176). Lower marital cohesion (Cohesion, subscale of the Dyadic Adjustment Scale) was related to elevated nighttime ABP (P < or = .05) and 24-h diastolic BP (P < .05). With low Cohesion (N = 83), more reported spousal contact was associated with elevated nighttime ABP (P < .031). The 7.3% of subjects with very low Cohesion demonstrated approximately 6 mm Hg elevation of all ABP variables, controlling for other significant variables (P < .05, except for nighttime SBP). This study shows an association between marital cohesion and ABP and suggests that marital factors may have a role in sustaining BP in early hypertension.

Adult↗

PubMed1998

Pulmonary circulatory parameters as indices for the early detection of acute rejection after single lung transplantation.

We investigated the relationship between the changes in the pulmonary blood flow and histology during acute rejection following single lung transplantation. In single lung transplantation using adult mongrel dogs, immunosuppression with cyclosporine and azathioprine was discontinued after postoperative day 14 to induce rejection. Doppler flow probes were placed adjacent to the ascending aorta and the left pulmonary artery to measure the blood flow on a daily basis. In addition, chest roentgenograms were also examined daily. The pulmonary pressure was measured using a Swan-Ganz catheter prior to and following the induction of rejection. Open lung biopsies were performed when the left pulmonary artery flow decreased to half of the prerejection value. The pulmonary artery flow decreased to 14.3% of the aortic flow 5 days after the discontinuation of immunosuppression. The graft pulmonary vascular resistance increased significantly compared to the prerejection values (P < 0.001). This was not accompanied by any abnormalities on chest roentgenography. The histology was consistent, with marked perivascular lymphocytic infiltration with little alveolar or interstitial changes. During rejection, the increased pulmonary vascular resistance in the graft was probably the result of perivascular inflammatory cell infiltration, which was seen prior to changes on chest roentgenography. Changes in the left pulmonary artery flow and histology thus appear to be closely correlated in the early stages of acute rejection.

Animals↗

PubMed1998

[Severe pulmonary hypertension due to mitral regurgitation without overt sign of congestive heart failure: a case report].

A 49-year-old man was found to have a heart murmur at a local hospital and was referred to our hospital for further examination. Although he had no signs of congestive heart failure, echocardiography and cardiac catheterization showed severe pulmonary hypertension caused by severe mitral regurgitation. Mitral valve replacement was performed, followed by reduction of pulmonary artery pressure. This patient had an unusual combination of no signs of lung congestion despite severe mitral regurgitation with pulmonary hypertension.

Echocardiography↗

PubMed1997

Quantitating dialysis using two dialysate samples: a simple, practical and accurate approach for evaluating urea kinetics.

Urea kinetics is now widely used to determine the adequacy of dialysis. Several simplified formulae are currently in use but only a few have been accepted into clinical practice because of their simplicity and ease of calculation. A recent analysis of these formulae showed that for the same set of blood urea values the calculated Kt/V can range from 1.0 to 1.5. We have developed a new dialysate-based method (2DSM) to estimate the urea kinetic parameters using dialysate and blood samples taken at the beginning and at the end of dialysis. The total urea removed (TUR) was calculated from the geometric mean of the two dialysate samples, dialysate flow rate and the duration of dialysis. The Watson formula was used to determine the volume of distribution of urea. A comparison of the 2DSM and the direct dialysate quantification (DDQ) method showed the following results (mean +/- sd, n = 52): for total urea removal (TUR) 697 +/- 32 vs 722 +/- 37 mmol (p = 0.6, r2 = 0.928, y = 101 + 0.83 x, mean difference 25 +/- 76 mmol, see Bland-Altman plot), dialysate urea concentration (Durea) 5.55 +/- 0.25 vs 5.75 +/- 0.29 mmol/l (p = 0.6, r2 = 0.928, y = 0.8 + 0.82 x, mean difference 0.2 +/- 0.6 mmol, see Bland-Altman plot), dialyser clearance (K) 232 +/- 4.4 vs 235 +/- 5.6 ml/min (p = 0.54), Kt/V 1.42 +/- 0.04 vs 1.51 +/- 0.04 (p = 0.21), volume of distribution of urea (Vd) 40.14 +/- 1.04 vs 38.74 +/- 1.2 L, (p = 0.38), and PCR 64.6 +/- 2.6 vs 68.1 +/- 3.1 g/day. We have developed a simple method of determining dialysate-based urea kinetics which requires two dialysate samples, one at the beginning and one at the end of dialysis and a blood sample at the midpoint of dialysis. TUR can be calculated using the dialysate flow rate and the dialysis duration and once this is known all the other kinetic parameters can be calculated.

Blood Specimen Collection↗

PubMed1996

Designing dialysis prescriptions.

Our objective was to determine the adequacy of dialysis in our patients currently on home peritoneal dialysis and develop a program of surveillance aimed at maintaining tKt/V (Kt/V calculated from peritoneal clearance and residual renal function) greater than 2.0 as recommended by the CANUSA study. Eighty-nine patients were entered into our study between September, 1993 and September, 1995. Initial dialysate volumes used during the training period were determined by using a patient-specific protocol. Two weeks after discharge a standard peritoneal equilibration test was performed to determine total Kt/V using a computer program, and dialysis prescriptions were changed to achieve a tKt/V > 2.0 in those patients who had tKt/V < 2.0, and those with tKt/V > 2.0 were followed without further intervention. Of the patients who had initial assessments, 33.7% had tKt/V of 1.65 and 66.3% had tKt/V of 2.46, and the difference was mainly due to residual renal function. Forty-four patients were started on continuous ambulatory peritoneal dialysis (CAPD), of whom 34% had tKt/V < 2.0 and 66% had tKt/V > 2.0, and of the 36 patients on continuous cycling peritoneal dialysis (CCPD), 30.5% had tKt/V < 2.0 and 69.5% had tKt/V > 2.0. The cost of changing dialysis prescriptions is less with CCPD than with CAPD, and a 0.8-1.0 L increase in dialysate volume will increase peritoneal Kt/V (dKt/V) by 0.1 on average. Patients weighing less than 53 kg can achieve a dKt/V > 2.0 even in the absence of residual renal function, but as body weight increases there is greater dependence on residual renal function to achieve adequate dialysis. We have been able to maintain patients on adequate dialysis (tKt/V > 2.0) by checking peritoneal clearance and residual renal function initially and on a regular basis. Whether a tKt/V > 2.0 will be sufficient to maintain health and well-being of our patients will require a longer period of observation.

Adult↗

PubMed1996

Non clamping anastomosis of the ascending and arch aneurysm using retrograde cerebral perfusion.

Twelve consecutive patients requiring surgery for replacement of ascending aortic aneurysms (n = 3), ascending arch aortic aneurysms (n = 2), or type A aortic dissections (n = 7) were treated without aortic cross clamping. Retrograde cerebral perfusion (RCP) with circulatory arrest (mean RCP time: 46.0 +/- 15.9 minutes, range 20 to 65 minutes) and continuous retrograde cardioplegia (mean cardiac ischemic time: 134.4 +/- 39.7 minutes, range: 40 to 180 minutes) were employed. In the patients with aortic dissection, the intimal tear at the origin of the brachiocephalic artery (BCA) was resected completely, the aortic wall was trimmed and closed with Teflon felt. The distal anastomosis was created using an open technique. Air and debris were completely evacuated by returning blood from the cerebral vessels and femoral artery. Then the artificial graft was clamped, and cardiopulmonary bypass resumed. The proximal anastomosis was performed during rewarming. The operations were elective in seven cases, and emergent in five cases. Graft replacement of the ascending aorta was performed in ten patients (including two BCA reconstructions). The remaining two patients were treated by patch repair (n = 1), primary anastomosis (n = 1). There were no perioperative deaths. One patient had a transient neurological deficit. The distal false lumen was occluded completely in five of seven patients with aortic dissections. The other two patients had a secondary tears in the descending aorta. Thus retrograde cerebral perfusion and continuous retrograde cardioplegia without aortic cross clamping is an effective technique in the replacement of the ascending and arch aorta.

Adult↗

PubMed1996

[Left ventricular pseudoaneurysm recognized 9 years after mitral valve replacement and repeated heart failure of 3 years duration: a case report].

A 66-year-old woman had suffered from repeated heart failure beginning 6 years after mitral valve replacement. Left ventricular pseudoaneurysm was discovered 9 years after the replacement, while no evidence including histology was obtained for the cause of the pseudoaneurysm except the mitral valve replacement. The progression of aortic valve stenosis and the formation of the pseudoaneurysm may have contributed to the onset of congestive heart failure. Surgical treatment was successful. Although left ventricular pseudoaneurysm after mitral valve replacement is rare, careful echocardiographic examination is necessary for detecting such a complication in patients after surgery.

Aged↗

PubMed1995

[Effect of reimplantation response on recipient pulmonary hemodynamics in single lung transplantation].

Until now, reimplantation response (RR) has been thought to be a transient dysfunction of the transplanted lung in single lung transplantation. How does RR influence on the native lung in single lung transplantation? We studied the influence of RR to the native lung with 20 dogs which were divided separated into 3 groups. In group I (6 dogs) and II (6), left lung allotransplantation without immunosuppression was performed. In group II, PGI2 was administered to the donors at 1 microgram/kg/min for 60 minutes iv drip infusion during lung extraction and super oxide dismutase (SOD) was administered to the recipients at 20 mg/kg just before reperfusion of the transplanted lung. In group III (8), allotransplantation with immunosuppression (CYA 20 mg/kg, AZ 4 mg/kg) was done using PGI2 and SOD in the same way as group II. In all groups doppler flow probes were attached to the ascending aorta and left pulmonary artery. For over 1 week, pulmonary hemodynamics was evaluated. In group I pulmonary arterial pressure increased up to 38.7 +/- 19.7 mmHg on 3 postoperative day, which showed significant difference (p < 0.05) from group II. An increase in vascular resistance of the transplanted lung was recognized right after transplantation in the both groups (0.212 +/- 0.058 mmHg/ml/kg to 0.487 +/- 0.114 in group I, 0.207 +/- 0.072 to 0.407 +/- 0.172 in group II). However, vascular resistance of the right lung increased in group I against group II right after transplantation (0.182 +/- 0.116 to 0.367 +/- 0.195 in group I, 0.183 +/- 0.116 to 0.214 +/- 0.149 in group II), which showed significant difference (p < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1994

Changes in pulmonary circulation during the early postoperative period following single lung transplantation.

This study examines the pulmonary hemodynamics during reimplantation and rejection following unilateral lung transplantation in dogs. Nineteen mongrel dogs were divided into three groups according to the method of treatment used: group 1 (n = 6) underwent modified autotransplantation of the left lung; group 2 (n = 6), allotransplantation without immunosuppression; and group 3 (n = 7), allotransplantation with immunosuppression. The pulmonary arterial blood flow and ventilation scores, assessed by chest X-rays, were measured for 2 weeks postoperatively. Pulmonary blood flow to the transplanted lung decreased slightly in group 1, whereas in group 2, it decreased sharply from the 3rd postoperative day (POD) and was almost completely absent by the 14th POD. In group 3, it decreased by 28% on the 1st POD but recovered gradually to 37% by the 14th POD. Ventilation scores were the same among the three groups on the 1st POD but in group 2, they decreased rapidly from the 3rd POD. This change correlated well with that of the pulmonary arterial (PA) flow, although the ventilation score changed after the PA flow did. In conclusion, rejection was reflected earlier and more distinctly by the changes in PA flow than by chest X-rays.

Animals↗