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J L Monro

Publications and source records attributed to J L Monro.

At least 37 records · Page 2Linked to original sources
PubMed2000

Surgical treatment of infective mitral valve endocarditis: predictors of early and late outcome.

BACKGROUND AND AIMS OF THE STUDY: The study aim was to review our experience in surgical treatment of infective mitral valve endocarditis, and to identify predictors of early and late outcome. METHODS: Ninety-one consecutive patients (52 males, 39 females, mean age 55.6 years) underwent surgery between 1973 and 1997 for endocarditis of isolated mitral (n = 65, 71%), mitral and aortic (n = 25, 28%) and mitral, aortic and tricuspid valves (n = 1, 1%). Native valve endocarditis (NVE) was present in 60 patients (66%) and prosthetic valve endocarditis (PVE) in 31 (34%). The main indications for surgery were heart failure in 32 patients, valve dysfunction in 23, vegetations in 21, and persistent sepsis in 11. Eighty-six patients (95%) were in NYHA classes III-IV, and 58 (64%) had active culture-positive endocarditis at surgery. Mechanical valves were implanted in 73 patients and bioprosthetic valves in 13; valves were repaired in five patients. The impact of 46 parameters on early and late outcome was defined by means of univariate and multivariate statistical analysis. Follow up was complete (mean 5.5 years; range: 0-23.1 years; total 507.3 patient-years). RESULTS: Operative mortality rate was 11% (n = 10). Recurrent infection was recorded in five patients (6%), and reoperation was required in eight (9%). Freedom from recurrent infection and reoperation at 10 years was 89.1% and 87.8% respectively. There were 22 late deaths, 15 from cardiac causes. Actuarial survival rates for all patients at 5, 10 and 15 years were 73.0%, 62.7% and 58.7% (for hospital survivors, the corresponding rates were 81.9%, 69.7% and 66.0%). On multiple logistic regression and Cox proportional hazards models, the following were independent predictors: preoperative pulmonary edema (p = 0.01) for operative mortality; PVE (p = 0.02) for recurrence; younger age (p = 0.02) and PVE (p = 0.02) for reoperation; male gender (p = 0.004) and longer ITU stay for survival (if all patients were included); male gender (p = 0.01) and myocardial invasion by infection (p = 0.02) for survival (if only the hospital survivors were analyzed). CONCLUSION: Surgery for infective mitral valve endocarditis carries a relatively high, though acceptable, risk but provides satisfactory freedom from recurrent infection, reoperation and improved long-term survival. Analysis of these data demonstrated that the preoperative hemodynamic status was the major predictor of in-hospital outcome, PVE increased the risk for recurrent infection and reoperation, whereas male gender and myocardial invasion by the infective process critically reduced the probability of long-term survival. The type of offending pathogen, the activity of infection and the involvement of more than one valve did not appear to influence early and/or late outcome.

Actuarial Analysis↗
PubMed2000

Mid-term results with 1,503 CarboMedics mechanical valve implants.

BACKGROUND AND AIM OF THE STUDY: The CarboMedics bileaflet prosthetic heart valve was introduced in 1986, and first implanted by the authors in March 1991. The aim of this study was to analyze the authors' clinical experience with this valve. METHODS: Between March 1991 and October 1998, 1,503 valves were implanted in 1,350 patients (758 males, 592 female; mean age 62 +/- 13 years). Follow up was 99% complete and totaled 4,342 patient-years (pt-yr). RESULTS: The hospital mortality rate was 4.3% (59/1,350). Preoperative NYHA class (p = 0.012), emergency surgery (p = 0.03) and cardiopulmonary bypass time (p = 0.01) were significantly associated with increased risk of operative death (multiple logistic regression). Mean (+/- SEM) survival rates at one and five years were 92.0 +/- 0.7% (n = 1,109) and 80.0 +/- 1.3% (n = 335). Freedom from valve-related complications (linearized rate 5.6%/pt-yr) at one and five years was 89.5 +/- 0.8% (n = 1,031) and 76.3 +/- 1.4% (n = 284). Linearized rates for bleeding events were 2.19%/pt-yr, thromboembolic events 2%/pt-yr, operated valvular endocarditis 0.18%/pt-yr, valve thrombosis 0.14%/pt-yr and non-structural dysfunction 1.22%/pt-yr. Freedom from reoperation at one and five years was 98.5 +/- 0.3% (n = 1,107) and 97.3 +/- 0.5% (n = 334). CONCLUSION: Mid-term results demonstrate that the CarboMedics prosthetic heart valve exhibits a low incidence of valve-related complications.

Aged↗
PubMed2000

Aortic valve replacement for endocarditis: determinants of early and late outcome.

BACKGROUND AND AIM OF THE STUDY: The study aim was to determine risk factors for operative mortality, recurrent infection, reoperation and long-term survival following aortic valve replacement (AVR) for infective endocarditis. METHODS: Between 1973 and 1997, 109 patients (91 male, 18 female, mean age 52.6 years) underwent isolated AVR for infective endocarditis in our unit. Native valve endocarditis was present in 89 (81.6%) and prosthetic valve endocarditis in 20 (18.4%). Active culture-positive endocarditis was present in 53 (48.6%). Preoperatively, 99 patients (90.8%) were in NYHA classes III and IV. Indications for surgery included cardiac failure in 41 patients, valvular dysfunction in 38, vegetations in 18, sepsis in seven, abscess in six and embolism in four. Mechanical valves were implanted in 69 patients (63.3%) and bioprostheses in 40 (36.7%), including a homograft in 19 (17.4%). Follow up was complete (mean 5.8 years; range: 0-23.8 years; total 633.5 patient-years). RESULTS: The operative mortality was 10.1% (11 deaths). At ten years, freedom from recurrent infection was 94.2%, and freedom from reoperation 83.6%. Biological valve and younger age were significant adverse parameters for freedom from reoperation (p = 0.01 and p = 0.01). There have been 21 late deaths, 15 due to cardiac causes. Kaplan-Meier survival, including operative mortality, at five and ten years was 77.4% and 68.0%, respectively. On Cox proportional hazards regression, Staphylococcus aureus infection (p = 0.008) and older age (p = 0.04) were independent adverse predictors of survival. CONCLUSION: AVR for endocarditis carries a relatively high operative mortality, but can result in a satisfactory freedom from recurrent infection, reoperation and long-term survival. Analysis of our series demonstrates that implantation of a biological valve limits the freedom from reoperation and that infection by Staph. aureus reduces the probability of long-term survival.

Adolescent↗
PubMed1999

Replacement of the proximal aorta and aortic valve using a composite bileaflet prosthesis and gelatin-impregnated polyester graft (Carbo-Seal): early results in 143 patients.

OBJECTIVE: We report the combined early results from two centers in the United Kingdom using a composite conduit consisting of a bileaflet mechanical valve incorporated into a gelatin-impregnated, ultra-low porosity, woven polyester graft (Carbo-Seal; Sulzer Carbomedics, Inc, Austin, Tex). METHODS: Between August 1992 and March 1997, 143 patients underwent aortic root replacement with the Carbo-Seal composite prosthesis. The indication for surgery was acute type A dissection in 31 (22%), chronic type A dissection in 9 (6%), ascending aortic aneurysm without dissection in 100 (70%), and false aneurysm of the ascending aorta in 3 (2%). Twenty-seven patients (19%) had undergone previous sternotomy, and 40 (28%) were seen as emergencies. Concomitant procedures were performed in 38 (27%), including 18 aortic arch or hemiarch replacements. Total follow-up is 270 patient-years. Follow-up is 100% complete. RESULTS: The early (30-day) mortality was 7% (10 patients). Permanent neurologic events occurred in 2%. At a mean follow-up of 23 months, 94% of survivors were in New York Heart Association functional class I. Freedom from reoperation was 97.2% +/- 1.6% (1 standard error [1 SE]) at 12 months and 95.7% +/- 2.2% at 48 months. Including early mortality, survival was 90.1% +/- 2.6% at 12 months and 83.1% +/- 3. 5% at 48 months. CONCLUSIONS: Aortic root replacement with use of the Carbo-Seal prosthesis can be undertaken with a relatively low early mortality and morbidity. A low reoperation rate and high intermediate-term survival can be expected, but continued follow-up is needed to determine the long-term efficacy of this prosthesis.

Aged↗
PubMed1999

Induced hypothermia as salvage treatment for refractory cardiac failure following paediatric cardiac surgery.

OBJECTIVE: Following corrective cardiac surgery in infants and children for congenital heart disease, a persistent low cardiac output refractory to conventional modes of treatment is associated with a mortality approaching 100%. We advocate the use of whole body hypothermia to reduce tissue oxygen demand and provide a degree of cellular protection against ischaemia allowing time for recovery. We describe our experience. METHODS: Between July 1986 and December 1995, 1885 infants and children underwent surgery (operative mortality, 6%), 1302 requiring cardiopulmonary bypass. Fifty-seven patients had a persistent low cardiac output, impaired respiratory function, decreased urine output and acidosis despite maximal intensive care treatment. Cooling to 32-33 degrees C was therefore started using a thermostatically controlled water filled cooling blanket. RESULTS: Following cooling, there was a fall in heart rate (P<0.001), a rise in mean arterial pressure (P<0.001) and a fall in mean atrial pressure (P<0.001). Significant (P<0.001) increases in pH and urine output were also recorded. Thirty-one (54%) of the 57 patients treated with cooling survived to leave hospital. No long-term sequelae have been noted in these patients. CONCLUSION: Induced hypothermia is a useful salvage treatment, in children following corrective cardiac surgery when all conventional treatment has been tried and failed.

Cardiac Output, Low↗
PubMed1999

Autotransfusion of washed shed mediastinal fluid decreases the requirement for autologous blood transfusion following cardiac surgery: a prospective randomized trial.

OBJECTIVES: The National Blood Service issues 2.2 million units of blood per year, 10% of these (220000) are utilized in cardiac procedures. Transfusion reactions, infection risk and cost should stimulate us to decrease this transfusion rate. We test the efficacy of autotransfusion following surgery in a prospective randomized trial. METHODS: One hundred and twelve patients undergoing CABG, valve or CABG + valve procedures were randomized into two groups. Group A received washed postoperative drainage fluid and group C were controls. The indication for transfusion was a postoperative haemoglobin (Hb) < 10 g/l or a PCV < 30. There was no significant difference in preoperative and operative variables between the groups. RESULTS: Twenty-eight patients in group A and 46 in group C required homologous transfusion (P = 0.0008). Group A patients required 298+/-49 ml of banked blood per patient, group C 508+/-49 ml (P = 0.003). There was no difference in total blood required (volume autotransfused + volume banked blood transfused) between the groups (group A 404+/-50 ml, group C 508+/-50 ml) or in mean total mediastinal fluid drainage (group A 652+/-51 ml, group C 686+/-50ml). The mean Hb concentration was significantly higher in group A on day 1 (11.2 g/dl+/-51 vs. 10.6 g/dl+/-13 (P = 0.002)). No morbidity was associated with autotransfusion. CONCLUSION: Autotransfusion can decrease the amount of homologous blood transfused following cardiac surgery. This represents a benefit to the patient and a decrease in cost to the health service.

Aged↗
PubMed1999

The fate of antibiotic sterilized aortic allografts in Fontan circulation: results of the long-term follow-up.

OBJECTIVE: Between 1977 and 1988, 27 patients, mean age 8.9 (range 4-22) received an antibiotic sterilised aortic allograft in the setting of the Fontan procedure. This study describes the long-term follow-up of these patients. METHODS: Fifteen patients had tricuspid atresia, nine double inlet ventricles and three others. The connection with the allograft was made to the pulmonary artery on the right side of the aorta in ten and to a left-sided main pulmonary artery in eight. In nine patients the allograft was anastomosed between the right atrium and the right ventricle. RESULTS: There were five early and five late deaths. One late death may have been allograft related. Survival was 81, 74 and 68% at 5, 10 and 15 years, respectively. Conduit calcification was universal. Twelve patients underwent reoperation, freedom from reoperation was 100, 88 and 54% at 5, 10 and 15 years following the initial Fontan procedure. At reoperation the gradient across the allograft was never more than 3 mmHg. The allograft was explanted with conversion to atriopulmonary or cavopulmonary connection in nine and a second allograft was inserted between the right atrium and right ventricle in two. No mortality occurred at reoperation. 41.1% of survivors still have their original allograft. CONCLUSIONS: Although there is a significant attrition rate allograft inclusion in the Fontan circulation does not change survival, but results in an increased reoperation rate. Inclusion of a valved conduit between the right atrium and ventricle does not usually enhance the growth potential of the rudimentary ventricle. All patients are in a good functional class which may represent the strict original selection criteria. The inclusion of a valve in the Fontan circulation is not recommended.

Adolescent↗
PubMed1999

Surgery for infective valve endocarditis in children.

OBJECTIVE: Surgery for endocarditis in children is relatively uncommon. Our aim is to assess operative mortality, recurrent infection, re-operation and long-term survival rates following surgery for infective valve endocarditis in children. PATIENTS: Sixteen consecutive children (ten female, six male, mean age 11.8 years, range 25 days-16 years) undergoing surgery between 1972 and 1999 in Southampton were studied. The aortic valve was affected in five, mitral in four, aortic and mitral in one, tricuspid in five and a pulmonary homograft in one patient. Prosthetic valve endocarditis was present in three. Twelve surgical interventions were emergency and four urgent. Indications for operation included cardiac failure in five, severe valvular dysfunction in nine, vegetations in nine, persistent sepsis in four and embolization in four patients. The offending micro-organism was identified in 13. Valve replacement was performed in 11 and excision of vegetations in two and excision of vegetations and repair in three. Follow-up was complete (mean 11.2 years, range 2 months to 26.3 years, total 179.5 patient years). RESULTS: There was one operative death (6.2%) in a 25-day-old neonate who presented in a moribund condition. Endocarditis recurred in one patient (6.25%). Freedom from recurrent infection at 10 and 20 years was 100.0 and 87.5%. Seven surgical re-interventions were required in four (25.0%) patients with no operative mortality. Freedom from re-operation at 1, 5, 10 and 20 years, was 84.6, 76.1, 76.1 and 60.9%, respectively. Two patients died 15 and 23 years after their first operation. The cause of the late deaths was non-cardiac in the first and unknown in the other. Actuarial survival, including operative mortality, at 1, 15 and 20 years was 93.7, 93.7 and 78.1%. CONCLUSIONS: Surgery in children with infective valve endocarditis can be performed with low operative mortality. Although some patients may require re-operation, freedom from recurrent infection and long-term survival are satisfactory.

Adolescent↗
PubMed1999

Diagnosis, management, and pathophysiology of post-Fontan hypoxaemia secondary to Glenn shunt related pulmonary arteriovenous malformation.

An 8 year old child with tricuspid atresia had developed right sided pulmonary arteriovenous malformations following a previous classic Glenn procedure. These became clinically manifest immediately after Fontan conversion because of severe systemic desaturation. The pathophysiology and postoperative medical management of this case is described and related to current understanding of the aetiology of acquired pulmonary arteriovenous malformations following cavopulmonary shunt.

Child↗
PubMed1999

Tricuspid valve replacement: bioprostheses are preferable.

BACKGROUND AND AIM OF THE STUDY: Tricuspid valve replacement (TVR) is rarely undertaken, most surgeons preferring to use conservative tricuspid valve procedures. Thus, limited data are available in patients following TVR. The purpose of this study was to analyze the early and late results in 87 patients (52 tissue valves, 35 mechanical prostheses) who underwent TVR between January 1973 and September 1996. METHODS: The patient group comprised 74 (85%) females and 13 (15%) males; mean (+/- SD) age was 59.4 +/- 12.8 years; range: 15 to 81 years). Forty-four patients (51%) had undergone at least one previous cardiac operation. There were 19 (23%) isolated TVRs, 43 (49%) triple valve replacements, and 25 (29%) double valve replacements. Total cumulative follow up was 707 patient-years (pt-yr) (tissue valves 393 pt-yr, mechanical valves 314 pt-yr); mean follow up was 8.1 years (range: 0 to 23.6 years). RESULTS: The early (30-day) mortality rate was 10.3% (n = 9; tissue 7, mechanical 2, p = 0.28). Logistic regression identified prolonged cardiopulmonary bypass time (p <0.03) and advanced NYHA functional class (p <0.007) as risk factors for operative death. No risk factors were significant on multiple logistic regression analysis. Mean (+/- SEM) survival rate was 68 +/-5.3% (n = 50) at 5 years, 52 +/- 5.9% (n = 36) at 10 years, 35 +/- 6% (n = 20) at 15 years, and 16 +/- 5.3% (n = 7) at 20 years. Freedom from tricuspid valve reoperation at 5, 10 and 15 years was 93 +/- 3.3% (n = 46), 83 +/- 5.8% (n = 33) and 71 +/- 2.8% (n = 17) respectively. Eleven patients required tricuspid valve reoperation: six mechanical valves (five for prosthetic valve thrombosis and one for mechanical failure secondary to pannus ingrowth), and five tissue valves (two for prosthetic valve endocarditis and three for prosthetic valve degeneration). Freedom from reoperation at 5, 10 and 15 years for tissue prostheses was 97 +/- 2.5%, 89 +/- 6.3% and it was 70 +/- 12%, and 86 +/- 7.4%, 74 +/- 9.9% and 68 +/-11% for mechanical prostheses. The mechanical prostheses required reoperation earlier after the initial surgery. CONCLUSIONS: We recommend the use of a bioprosthesis in the tricuspid position because of its initial durability and low reoperation rate.

Adolescent↗
PubMed1999

Twenty-year follow-up of aortic valve replacement with antibiotic sterilized homografts in 200 patients.

The aim of this study was to determine long-term results from one unit of subcoronary homograft aortic valve replacement (AVR) using the same sterilization and preservation techniques in each case. Between 1973 and 1983, 200 patients underwent AVR using an unstented homograft previously sterilized in antibiotics and preserved at 4 degrees C. Surviving patients were monitored for a minimum of 15 years to the end of 1998. Mean age was 50.0+/-14 (1 standard deviation) years; 121 patients were men (60.5%). Mean patient follow-up time was 15.6+/-6.7 years, with a total follow-up time of 3,115 patient years. Follow-up was 95.6% complete. There were three early deaths (1.5%). At autopsy, the homograft was anatomically normal and in a satisfactory position. Kaplan-Meier survival, including early death, was 81.2%+/-2.8% (1 standard error) at 10 years, 68.1%+/-3.4% at 15 years, and 58.0%+/-3.7% at 20 years. Repeat AVR was undertaken in 74 patients, giving a freedom from reoperation for any reason of 86.5%+/-2.6%, 69.6%+/-3.8%, and 38.8%+/-5.3% at 10, 15, and 20 years, respectively. Freedom from structural valve degeneration at 10, 15, and 20 years was 81.1%+/-2.9%, 61.7%+/-3.9%, and 31.2%+/-4.7%, respectively. Freedom from endocarditis at 10, 15, and 20 years was 98.7%+/-0.9%, 96.0%+/-1.8%, and 94.6%,+/-2.3%, respectively. Homograft AVR with an antibiotic-sterilized valve stored at 4 degrees C and implanted in the subcoronary position offers low operative mortality and good long-term outcome for patients.

Antibiotic Prophylaxis↗
PubMed1998

Right ventricular function and exercise performance late after primary repair of tetralogy of Fallot with the transannular patch in infancy.

To evaluate the late effects of chronic pulmonary regurgitation against the putative benefits from the current surgical trend of primary repair of tetralogy of Fallot with a transannular patch in infancy, 10 patients > 10 years after early primary repair and 7 matched normal controls underwent exercise stress test and cine magnetic resonance imaging assessment of ventricular functions. Right ventricular impaired diastolic function and decreased exercise capacity, both significantly associated with pulmonary regurgitation in patients, indicated that early primary repair of tetralogy may not prevent late ventricular dysfunction and diminished exercise performance if chronic regurgitation results from right ventricular outflow tract reconstruction.

Adolescent↗
PubMed1998

Degenerative mitral regurgitation: when should we operate?

BACKGROUND: Left untreated, severe mitral regurgitation in asymptomatic patients can lead to irreversible cardiac damage, which can develop with little warning. Over the period of this study, we have tended to operate earlier in the disease process and on less symptomatic patients. We report here our experience. METHODS: Between January 1985 and June 1996, 710 patients with mitral regurgitation underwent operations. Three hundred twenty-nine (213 male and 116 female with a mean age of 65.5 years) had degenerative mitral valve disease and of this group, 169 patients underwent repair and 160, replacement. RESULTS: The overall operative mortality was 4 patients (1.2%). There were no operative deaths among patients having isolated mitral valve repair. Survival at 1 year, 5 years, and 10 years was 94%+/-1.4% (+/- the standard error of the mean), 77%+/-2.9%, and 41%+/-5.8%, respectively. Survival was significantly better in the group having repair (p < 0.05). Ten patients (6%) in the repair group and 13 (8%) in the replacement group required reoperation. Increased age, worse left ventricular function, type of operation (replacement worse than repair), and increased left ventricular size were significantly associated with poorer survival. CONCLUSIONS: These data confirm the superior results achieved with mitral valve repair and support early mitral valve repair before functional deterioration.

Adolescent↗
PubMed1998

Should coronary artery bypass grafting be performed at the same time as repair of a post-infarct ventricular septal defect?

OBJECTIVE: The value of coronary artery bypass grafting (CABG) at the time of repair of a post-infarct ventricular septal defect (VSD) remains controversial. The aim of this study was to analyse the effect of CABG on early mortality and survival following repair of an acquired VSD. METHODS: Over 23 years, 179 patients, 118 male, 61 female, mean age 66 years (range 43-80), have undergone repair of a post-related VSD in our unit. A total of 29 patients, who predominantly form the earlier part of the series, were operated on greater than 1 month after the infarct and are, therefore, excluded. Coronary angiography was performed in 98 (65.3%) of the remaining 150 patients. Of these, 41 had coronary artery disease (CAD) limited to the infarct-related vessel and 57 had additional significant CAD. Those with CAD limited to the infarct-related vessel were not grafted (Group A). Of those, 40 with significant CAD underwent CABG at the time of VSD repair (Group B) and 17 did not (Group C). In 52 patients the coronary anatomy was not documented (Group D). Risk factors for early mortality were evaluated using logistic regression. Actuarial survival was compared using log rank and Wilcoxon tests. Cox's proportional hazards method was used to determine factors affecting survival. RESULTS: Overall, 30 day mortality was 32%. CABG did not significantly decrease operative mortality (logistic regression). There was no statistically significant difference in early mortality or actuarial survival between the four groups. CABG was not associated with an increased survival (Cox's method). CONCLUSIONS: Concomitant CABG at the time of VSD repair does not affect early mortality nor confer survival benefits. There seems to be no demonstrable benefit in revascularisation at the time of repair and, therefore, it may be unnecessary to perform CABG or coronary angiography in these patients.

Adult↗
PubMed1998

Cerebral oxygenation during paediatric cardiac surgery: identification of vulnerable periods using near infrared spectroscopy.

OBJECTIVE: Neurologic sequelae remain a well recognised complication of paediatric cardiac surgery. Monitoring of cerebral oxygenation may be a useful technique for identifying vulnerable periods for the development of neurologic injury. We sought to measure regional cerebral oxygenation in children undergoing cardiac surgery using near infrared spectroscopy to ascertain such vulnerable periods. METHODS: Observational study of 18 children (median age 1.3 years) undergoing cardiac surgery (17 with cardiopulmonary bypass, 8 with circulatory arrest). Regional cerebral oxygenation was monitored using the INVOS 3100 cerebral oximeter and related to haemodynamic parameters at each stage of the procedure. RESULTS: Prior to the onset of bypass, 10 patients had a decrease in regional cerebral oxygenation of > or = 15% points, reaching an absolute haemoglobin saturation less than 35% in 5 cases. The most common cause was handling and dissection around the heart prior to and during caval cannulation. With institution of bypass, regional cerebral oxygenation increased by a mean 18% points to a mean maximum of 75%. During circulatory arrest regional cerebral oxygenation decreased with rate of decay influenced by temperature at onset of arrest (0.25%/min at < 20 degrees C; 2%/min at > 20 degrees C). Reperfusion caused an immediate increase in regional cerebral oxygenation followed by a decrease during rewarming. Discontinuation of bypass caused a precipitous decrease in regional cerebral oxygenation in 5 patients, reaching less than 50% in 3 patients. CONCLUSIONS: These observations suggest that the pre- and early post-bypass periods are vulnerable times for provision of adequate cerebral oxygenation. Near infrared spectroscopy is a promising tool for monitoring O2 supply/demand relationships especially during circulatory arrest.

Brain↗
PubMed1998

Effects of angiotensin converting enzyme inhibition on systemic vascular resistance and vasoconstrictor requirements during hypothermic cardiopulmonary bypass.

OBJECTIVE: We proposed that angiotensin converting enzyme (ACE) inhibitor therapy would alter systemic vascular resistance (SVR) during rewarming and increase the requirement for vasoactive drugs in the immediate post-bypass period. METHODS: Sixty-five sequential adult patients undergoing cardiac surgical procedures requiring hypothermic (28 degrees C) cardiopulmonary bypass (CPB) were recruited. Sixty-two fitted the inclusion criteria of which 21 were receiving ACE inhibitors prior to surgery. SVR was calculated at 1 min intervals during the rewarming phase of hypothermic CPB. The use of vasoactive drugs during and immediately after termination of CPB was recorded. The doctor administering these drugs was unaware of the nature of the study. RESULTS: Mean SVR in the ACE group was 978 dyne/s per cm5 and in the control group was 1194 dyne/s per cm5 (P = 0.006). Mean arterial pressure was 48.8 mmHg in the ACE group and 56.3 mmHg in the control group (P = 0.004). There was a significant difference in vasoactive drug requirements between the groups (P < 0.01). There was no statistically significant difference in age, weight, body mass index, body surface area, theatre temperature, core temperature at which rewarming started, rate and time of rewarming, haematocrit on bypass or preoperative left ventricular function. CONCLUSION: Preoperative ACE inhibitor therapy decreases SVR during the rewarming phase of CPB and increases post-bypass vasoactive drug requirements.

Aged↗
PubMed1998

When is extracorporeal life support worthwhile following repair of congenital heart disease in children?

BACKGROUND: Although the use of extracorporeal life support (ECLS) following repair of congenital heart defects in children is increasing, the criteria for ECLS usage in these patients is not well defined. The overall survival of such patients is disappointingly low and may depend on both the indication for support and the time at which ECLS is commenced. METHODS: Between January 1993 and December 1996, 727 children underwent surgery for congenital heart defects at our institution with an overall hospital mortality of 5.8% (42 children). Nine of these children were treated with ECLS postoperatively. There were seven males and two females with a mean age of 7.2 months (range 2 weeks-3 years). Seven children could not be weaned from cardiopulmonary bypass (CPB) in the operating theatre. A further two were treated with ECLS later on during the postoperative period (commenced at 14 and 48 h). Full veno-arterial extra corporeal membrane oxygenation (ECMO) support was used in all children except one in whom a left ventricular assist device (LVAD) was used. RESULTS: The median duration of support was 121 h (range 15-648 h). Four children (44%) were weaned from support and two of these are long-term survivors. Of the seven children in whom ECLS was instituted because of failure to wean from CPB, there was one long term survivor (LVAD support). Of the two patients in whom ECLS was instituted during the post-operative period there is one long-term survivor. CONCLUSIONS: Weaning form ECLS and decannulation in 44% of our patients is comparable to other series of post-cardiotomy patients requiring ECLS. However, full veno-arterial ECMO instituted because of a failure to wean from CPB during corrective surgery is associated with an extremely poor outcome (zero long-term survivors in six patients).

Child, Preschool↗