Search PubMed⌕ Search

Biomedical subjects

C Antona

Publications and source records attributed to C Antona.

At least 37 records · Page 2Linked to original sources
PubMed1997

[Surgical therapy for prosthetic infections of the thoracic aorta. Conservative approach].

The prosthetic graft infection of the thoracic aorta is a dreaded complication and it is associated with a high mortality rate. There is not substantial agreement in literature about how to manage a vascular graft infection, except for local anti-septic irrigation with a systemic antibiotic therapy. The main point of discussion is if it is mandatory to remove or not the infected thoracic aorta prosthesis: some authors prefer to eliminate all the thoracic aortic prostheses which may be infected, while others propose graft removal only when the sutures lines are involved. In this paper we report our experience on the conservative management of infected thoracic aorta prostheses using a local antiseptic irrigation, a perigraft debridement and leaving the original graft "in situ" when there is evidence of graft damage especially or involvement of the sutures lines. This approach has been performed in three patients: two had an infected aortic arch prosthesis, while one had a descending thoracic aorta prosthesis infection.

Aorta, Thoracic↗
PubMed1997

[Surgery of the ascending aorta: the 1984-1995 experience of the cardiac surgery teaching unit in the University of Milan. Multivariate analysis of its risk factors for hospital mortality and reduced long-term survival].

Between 1984 and 1995, 183 patients underwent an ascending aorta procedure at our institution. Their mean age was 60 +/- 12.3 years; 116 (63.4%) patients were male, 35 (19.1%) had a history of congestive heart failure, 72 (39.3%) presented acute type A dissection, 23 (12.6%) were redos and 63 (34.4%) were operated on an emergency basis. In-hospital mortality was 10% (12/120) in elective procedures and 36.5% (23/63) in emergency operations (p < 0.0001). Multivariate stepwise logistic regression analysis identified cardiopulmonary by-pass time, emergency operation, arch replacement and the need for femoral vein cannulation at surgery as independent predictors of in-hospital death. Mean follow-up time was 54 +/- 30 months (median 50 months), with a Kaplan-Meier survival of 69 +/- 4% and of 60 +/- 5% at 5 and 7 years, respectively. Cox regression analysis identified arch replacement, perioperative myocardial infarction, preoperative NYHA class, acute type A aortic dissection, the need for femoral vein cannulation at intervention and redo operations as independent predictors of reduced survival at follow-up. When this kind of analysis was performed on hospital survivors only, postoperative tracheostomy, reexploration for bleeding, and the occurrence of postoperative ventricular arrhythmias emerged as risk factors. In conclusion, multiple factors affect both early and long-term outcome following ascending aorta surgery. Preoperative clinical status of patients, priority of surgery and aortic dissection are the main determinants of the short-term results. Otherwise, in hospital survivors, the main determinant for long-term outcome seems to be the immediate postoperative course.

Aged↗
PubMed1996

Retention of endothelium-dependent properties in human mammary arteries after cryopreservation.

BACKGROUND: We investigated the effects of cryopreservation and antibiotic treatment on endothelium-dependent vasomotor properties of human internal mammary arteries (IMAs). METHODS: Sixty IMA specimens from routine coronary artery bypass grafting procedures were randomly assigned to six groups. Group I (controls) were immediately tested after harvest. Remaining groups were prepared according to a stepwise design: group II, 6 hours of warm ischemia; group III, 6 hours of warm ischemia + 24 hours at 4 degrees C (without antibiotics); group IV, 6 hours of warm ischemia + 24 hours of 4 degrees C antibiotic disinfection; group V, 6 hours of warm ischemia + 24 hours at 4 degrees C (without antibiotics) + cryopreservation; and group VI, 6 hours of warm ischemia + 24 hours of 4 degrees C disinfection+cryopreservation. The IMA specimens were cut into rings and the tension of vascular smooth muscle was recorded. The IMA rings were contracted with norepinephrine (3 x 10(-6) mol/L) and tested with cumulative concentrations of acetylcholine (from 1 x 10(-9) to 1 x 10(-5) mol/L), contracted with endothelin-1 (from 1 x 10(-11) to 1 x 10(-6) mol/L), and contracted with the nitric oxide-synthase inhibitor NG-monomethyl-L-arginine (1 x 10(-4) mol/L). Rings were also tested for their capacity to generate 6-keto-prostaglandin F1 (the stable metabolite of prostacyclin), and endothelial cell viability rate was finally evaluated with the trypan blue dye exclusion method. RESULTS: Our results show that a complete cryopreservation protocol does not significantly modify (p > 0.05) the relaxant activity to acetylcholine in norepinephrine-precontracted IMA rings (controls; 90.2% +/- 4.2% vs group VI, 77.1% +/- 6.2%) or the vasoconstrictor response induced by endothelin-1 (controls, 62.6% +/- 2.8% versus group VI, 73.7% +/- 4.8%) and NG-monomethyl-L-arginine (controls, 22.4% +/- 1.5% versus group VI, 18.9% +/- 1.9%). Furthermore, IMA cryopreservation does not significantly modify (p > 0.05) the endothelial release of prostacyclin either in basal conditions (-20% versus controls) or during pharmacologic intervention with acetylcholine (-18% versus controls), endothelin-1 (-17% versus controls), and NG-monomethyl-L-arginine (-18% versus controls). CONCLUSIONS: We conclude that the IMA endothelial function does not seem significantly injured by any of the current steps of disinfection and cryopreservation.

6-Ketoprostaglandin F1 alpha↗
PubMed1996

Midterm angiographic study of five recycled mammary arteries during four coronary redos.

BACKGROUND: Recently the technical feasibility of reusing the left internal mammary artery (IMA) in coronary artery reoperation has been documented, but the patency of "recycled" IMAs has not yet been established. METHODS: In 4 patients undergoing coronary reoperation, five internal mammary arteries (3 left IMAs and 2 right IMAs) that were patent but severely stenotic at the anastomotic site were taken down and reused. In 2 cases the IMAs were reanastomosed to the same target coronary artery, in 2 cases the IMAs were rerouted to another coronary artery, and in 1 case an interposition of a short segment of the greater saphenous vein was needed to reach the target coronary artery. RESULTS: Angiographic midterm evaluation, performed between 7 and 35 months postoperatively, showed patency of all the reused grafts without stenoses. CONCLUSIONS: When feasible, recycling of the IMAs may be considered if one or both IMAs have been previously used and are stenotic in the perianastomotic area, or when there is a stenosis in the native coronary artery distal to the anastomosis itself.

Adult↗
PubMed1996

Role of right gastroepiploic artery in myocardial revascularization with arterial grafts.

Between July 1990 and December 1992. 112 patients underwent myocardial revascularization with arterial grafts in the Department of Cardiac Surgery, University of Milan. Monovascular patients were excluded from the study. The right gastroepiploic artery was used in 44 patients (39.3%); mean age was 54.3 years and reoperation rate 18.2%. Of the 44 patients, previous myocardial infarction had occurred in 25 (57%). Emergency operation was performed in one case (2%). Mean left ventricular shortening fraction was 36% and mean ejection fraction 58.6%. Coronary artery disease was bivascular in 10 patients (23%) and trivascular in 34 (77%). The arterial revascularization in patients with gastroepiploic artery was performed using a left internal thoracic artery graft in all 44 patients; the right internal thoracic artery was used in 18 (41%) and the inferior epigastric artery in two (4%). The sites of gastroepiploic artery grafting were 55% posterior descending, 16% right coronary artery, 11% posterolateral branch, 14% circumflex and in 4% posterior descending and posterolateral as sequential graft. No patient died; postoperative myocardial infarction rate was 4%. No complications related to gastroepiploic artery utilization were noted. Forty-three (98%) of the gastroepiploic artery group underwent graft reinvestigation: the arteries were correctly visualized in 41 patients (95%) and were patent in 39 cases and stenotic in two. A mid-term postoperative stress test (mean 17.4 months) was performed in 91% of patients. Normal limits were found in 37 patients (92.5%) and an abnormal stress test result in three (7.5%). The contemporary follow-up showed no deaths or myocardial infarctions. Three patients (7%) had recurrent angina. The role of gastroepiploic artery in arterial revascularization has become fundamental, especially, it is believed, for the posterior or posterolateral left ventricular wall. The present data show the patients to be clinically and functionally well 1 year after operation.

Adult↗
PubMed1996

Pedicled arterial grafts in coronary surgery: postoperative echo color-Doppler study.

In 1994 a mid-term postoperative echo color-Doppler ultrasound was performed to check the pedicled arterial conduits used in coronary surgery, such as the left and right internal mammary arteries (LIMA, RIMA) and the right gastroepiploic artery (RGEA). This evaluation was made in 31 patients with a previous nonemergent complete arterial myocardial revascularization. The pedicled arterial grafts studied were 71 (31 LIMA, 15 RIMA and 25 RGEA). The Doppler spectrum (combined systolic/diastolic waveform), the diameter and the flow of every arterial graft was always identified (100% of detection) and there was a statistical significative difference between mean RGEA flow versus mean LIMA and RIMA flow (p<0.05). All the conduits studied were characterized by a good diastolic and end-diastolic velocity, evidence of normal graft patency. The postoperative angiogram of the LIMA, RIMA and RGEA conduits was performed in 27/31 (87.1%) patients and it showed 100% patency of arterial grafts used and of anastomoses. The echo color-Doppler data were compared to postoperative angiographic results. The echo color-Doppler imaging of the pedicled arterial grafts used in coronary surgery seems to be a promising technique for the postoperative serial assessment of the LIMA, RIMA and RGEA conduit function, because it is noninvasive, safe, easy, quick to perform and the preliminary results of echo color-Doppler ultrasound versus angiography are satisfactory.

Adult↗
PubMed1996

[Heart surgery, cardiopulmonary bypass and inflammatory response. I. Changes in hemostasis and complement].

The use of cardiopulmonary bypass for surgical cardiac procedures is characterized by a whole-body inflammatory reaction due to the contact of blood through nonendothelialized surfaces; this stimulates the organism to recognize the cardiopulmonary bypass system as "nonself" and to activate specific (immune) and nonspecific (inflammatory) responses. These responses are then related with postoperative damage to many body systems, like pulmonary, renal or brain dysfunction, excessive bleeding and postoperative sepsis. In this paper, present knowledge on untoward responses of the patient to the use of cardiopulmonary bypass in cardiac surgery is reviewed and discussed, particularly focusing on the perturbation of the hemostasis and of the complement activation system.

Blood Coagulation↗
PubMed1996

[Heart surgery, cardiopulmonary bypass, and organic inflammatory response. Part II: changes in leukocytes, arachidonic acid derivatives, and hormones].

The use of cardiopulmonary bypass for surgical cardiac procedures is characterized by a whole-body inflammatory reaction due to the contact of blood through nonendothelialized surfaces; this stimulates the organism to recognize the cardiopulmonary bypass system as "nonself" and to activate specific (immune) and nonspecific (inflammatory) responses. These responses are then related with postoperative damage to many body systems of the body, like pulmonary, renal or brain dysfunction, excessive bleeding and postoperative sepsis. In this paper, present knowledge on untoward responses of the patient to cardiopulmonary bypass in cardiac surgery is reviewed and discussed, particularly focusing on the perturbation of the leukocytes, of the hormones and of the products of the arachidonic acid cascade.

Arachidonic Acids↗
PubMed1996

Myocardial revascularization procedures on multisegment diseased left anterior descending artery: endarterectomy or multiple sequential anastomoses (jumping)?

Complete revascularization is the primary goal in coronary surgery because of its superior long term results. However, in some patients the extent of the coronary artery disease is such that the usual coronary bypass technique may not allow to perform a complete myocardial surgical revascularization and, consequently, a satisfactory myocardial perfusion: so complementary revascularization techniques may become mandatory, especially when the diseased vessel is LAD or its branches. As a consequence, alternative procedures should be undertaken: coronary endarterectomy (EA) and multiple sequential anastomoses on a single vessel (jump), which guidelines are actually somehow controversial. Between January, 1989, and May, 1992, 53 patients underwent a myocardial revascularization procedure on LAD system unsuitable for single distal bypass; of them 35 (66%) underwent coronary endarterectomy, while in 18 (34%) multiple sequential anastomoses (jumping) were performed on the same vessel. About preoperative variables, average NYHA class (2.7 jump vs 2.1 EA group, p < 0.05), the history of more than 1 myocardial infarction (22.2% jump vs 2.9% EA, p < 0.04) and the presence of preoperative nitrates e.v (33.3% vs 8.6%, p < 0.04) were statistically higher in the jump group, suggesting a more unstable clinical status, while other clinical echocardiographic and catheterization features were not statistically different. For what operative and postoperative features are concerned, the number of anastomoses performed was statistically higher in the jump group, as exasperated (3.8 vs 2.7, p < 0.002) while perfusion (138 vs 141 min) and crossclamp time (103 vs 106 min) were similar. Furthermore we found a statistically lower incidence of perioperative myocardial infarction (0% jump is 22.8% EA group, p < 0.04); the postperfusion inotropic drugs requirement (22.2% vs 37.1%), the need of an intraaortic counterpulsation (0% vs 2.9%) and the in-hospital mortality (0% vs 5.7%) were lower in the jumping group too, also if they didn't reach statistical significance. Our experience suggest, also with the limits imposed by a retrospective case review and by a low number of cases reported, that myocardial revascularization of a multisegment diseased LAD system may be safely performed with the jumping technique with a low incidence of postoperative complications: it should be the first choice technique when conventional revascularization procedures are not enough to achieve complete myocardial revascularization. We advocate the use of EA technique only in that cases characterized by a diffuse atherosclerotic core and a well delimited plane of dissection, associated to a very poor runoff, which really excludes any chance to multiple anastomoses.

Aged↗
PubMed1995

The effect of "high dose" aprotinin and other factors on bleeding and revisions for bleeding in adult coronary and valve operations: an analysis of 2190 patients during a five-year period (1987-1991).

We retrospectively evaluated risk factors for postoperative bleeding and for revisions due to bleeding in 2190 adult coronary and valve patients who underwent surgery at our hospital during the 5-year period from 1987 to 1991. During this period 889 (40.6%) patients were given "high dose" aprotinin. Their mean age was 59.3 +/- 8.8 years, 1636 (74.7%) were males, 200 (9.1%) underwent surgery on an emergency basis and 72 patients (3.3%) underwent redo-operations. The patients were divided into four groups according to the type of surgery: all patients pooled together (2190), coronary artery surgery patients (1384, 63.2%, group I), valve surgery patients (706, 32.2%, group II) and combined (coronary plus valve) surgery patients (100, 4.6%, group III). Stepwise logistic regression analysis, performed to assess the risk factors for revisions due to bleeding showed aprotinin treatment to be the sole protective factor in all patients, group I and group II. In group III only the use of a hollow fiber membrane oxygenator proved a protective factor. Risk factors for revisions for bleeding were found to be aortic cross-clamp time in all patients, group I and group II. Use of the internal thoracic artery (ITA) was significant in group I patients and age at operation in group II. Multiple stepwise linear regression analysis, performed to evaluate the effect of various risk factors on cumulative postoperative blood loss in all patients, confirmed aprotinin as the only factor capable of reducing blood loss, while aortic cross-clamp time, coronary surgery and male gender showed a positive linear relation with postoperative bleeding.(ABSTRACT TRUNCATED AT 250 WORDS)

Aprotinin↗
PubMed1995

The effect of multiple blood conservation techniques on donor blood exposure in adult coronary and valve surgery performed with a membrane oxygenator: a multivariate analysis on 1310 patients.

The object of the study was to retrospectively evaluate protective and risk factors for receiving donor blood products and red cell transfusions after coronary and valve surgery performed with a hollow-fiber oxygenator and with multiple blood-saving techniques. During the period of January 1991 to June 1993, 1310 patients underwent primary coronary and valve surgery using a hollow-fiber oxygenator at our institution; the mean age of this population was 61 +/- 10 years; 977 patients were men (74.6%). Of these patients, 73.5% (963/1310) underwent coronary, 21.5% (281/1310) valve, and 5% (66/1310) combined surgery. Two hundred seventy-six (21.1%) needed donor blood product transfusions, while 153 (11.7%) patients underwent red cell transfusions. Significant risk factors for homologous blood product exposure after multivariate logistic regression analysis were, in order of importance: (1) postoperative blood loss (O.R. = 1.0009 per mL, p = 0.0000); (2) cardiopulmonary bypass (CPB) time (O.R. = 1.008 per min, p = 0.0001); (3) age at intervention (O.R. = 1.031 per calendar year, p = 0.0026); and (4) reoperation for bleeding (O.R. = 1.71, p = 0.0078). Protective factors were: (1) male gender (O.R. = 0.56, p = 0.0000); (2) preoperative withdrawal of autologous blood (O.R. = 0.66, p = 0.0018); and (3) a preoperative hematocrit greater than 34% (O.R. = 0.76, p = 0.0005).(ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗
PubMed1995

Ectopic thyroid tissue in the ventricular outflow tract: embryologic implications.

The case of a 66-year-old female patient with a tumor located in the right ventricular outflow tract is reported. Histologic examination of an intraoperative biopsy revealed that the tumor was an intracardiac ectopic thyroid. We performed conservative surgery with partial resection of the mass. After 5 years, the patient is asymptomatic and leading a normal life. The authors examine the relation between the embryologic development of the primitive heart and the thyroid primordium and suggest the hypothesis of ectopic thyroid location in the right- or left-ventricular outflow tract.

Aged↗
PubMed1995

Systemic to pulmonary bronchial blood flow in heart failure.

STUDY OBJECTIVE: The aim of this study was to measure systemic to pulmonary blood flow from bronchial circulation (Qbr[s-p]) in patients with heart failure. DESIGN: In the absence of pulmonary and coronary flows, Qbr(s-p) is the volume of blood accumulating in the left side of the heart; Qbr(s-p) was measured during total cardiopulmonary bypass for coronary artery surgery; bronchial blood was vented through a cannula introduced into the left side of the heart and its volume was measured. PATIENTS: Patients were subdivided according to the presence for more than 6 months (group 1, n = 6) or less than 2 months (group 2, n = 7), or the absence of heart failure (group 2, n = 15). MEASUREMENTS AND RESULTS: Qbr(s-p) was 89 +/- 18* mL/min, 27 +/- 3, 22 +/- 2, in groups 1, 2, and 3, respectively (* = p < 0.01 group 1 vs groups 2 and 3). During total cardiopulmonary bypass, pulmonary venous pressure approximates atmospheric pressure and no differences between groups were observed in systemic artery pressure, extracorporeal circulation pump flow, and airway pressure. Therefore, vascular resistance through the bronchial vessels draining into the pulmonary circulation is reduced in patients with heart failure for more than 6 months (group 1). CONCLUSIONS: During total cardiopulmonary bypass, Qbr(s-p) is increased in patients with chronic heart failure. Since with elevated pulmonary vascular pressure blood flow through Qbr(s-p) vessels is from the pulmonary to the systemic circulation, the lower resistance observed in group 1 suggests that bronchial vessels might contribute to reduced lung fluid overload in patients with chronic heart failure.

Adult↗
PubMed1995

One month follow-up of haemostatic variables in patients undergoing aortocoronary bypass surgery. Effect of aprotinin.

It is already known that activation of the coagulation and fibrinolytic system occurs in patients undergoing cardiopulmonary bypass (CPB). We have thus studied twenty patients (10 treated with aprotinin during CPB and 10 untreated) both during the intraoperative period and during thirty days follow up. In untreated patients D-dimer levels increased 4-fold during CPB and the levels were above baseline for the whole follow up (p < 0.0001). D-dimer levels were reduced in aprotinin treated patients in comparison to untreated patients (p = 0.0172); levels then gradually increased to the values of the untreated patients over the following 24 h later and remained higher during the thirty day follow up. The behavior of haemostatic variables in the 24 h after CPB did not vary between untreated and aprotinin treated patients. In particular, five minutes after protamine sulphate administration, levels of F1 + 2 and TAT rose significantly (p = 0.0054, p = 0.0022 respectively), whereas fibrinogen significantly decreased (p < 0.0001) and PAI-1 antigen levels were reduced. Two days after CPB the concentrations of F1 + 2 and TAT lowered, whereas fibrinogen and PAI-1 antigen levels increased. On the 5th, 8th and 30th days after CPB, F1 + 2 and TAT levels remained higher than those reported at baseline in both groups of patients, whereas fibrinogen levels increased over basal levels in aprotinin treated patients only. Thus, in addition to the activation of the coagulation and fibrinolytic system occurring during the intraoperative period, in patients undergoing CPB, there are alterations of haemostatic variables up to thirty days from surgery.

Aged↗
PubMed1994

Prostacyclin production by different human grafts employed in coronary operations.

Segments of human saphenous vein, internal mammary artery, right gastroepiploic artery, and inferior epigastric artery were incubated in vitro in Krebs-Henseleit solution and compared in terms of their capacity to generate and release into the medium 6-keto-prostaglandin F1 alpha (PGF1 alpha), the stable metabolite of prostacyclin. The four vascular conduits were also challenged with endothelin-1 (40 ng/mL), and accumulation of the lipidic material in the bathing fluid was also studied. The results obtained show clearly that under both normal and endothelin-1-stimulated conditions, the four vascular segments generate a substantial amount of 6-keto-PGF1 alpha. Multiple-comparisons analysis of the results indicates that the rank order in producing 6-keto-PGF1 alpha is as follows: inferior epigastric artery > internal mammary artery > right gastroepiploic artery > saphenous vein (p < 0.01). A similar order of potency was obtained in vascular conduits stimulated with endothelin-1. The rate of formation of immunoreactive 6-keto-PGF1 alpha under both normal and stimulated conditions by the inferior epigastric artery (normal, 301 +/- 8 pg/mg of tissue; stimulated, 519 +/- 15 pg/mg of tissue) was at 10 minutes more than 2 times (p < 0.01) that of the saphenous vein and about 1.5 times (p < 0.01) that of the right gastroepiploic artery.(ABSTRACT TRUNCATED AT 250 WORDS)

6-Ketoprostaglandin F1 alpha↗
PubMed1994

[A case of complete myocardial revascularization with different arterial grafts: right internal mammary artery, right gastroepiploic artery and inferior epigastric artery].

It has been well established that the internal thoracic artery (ITA) is a good alternative to the saphenous vein as conduit for coronary artery bypass grafting because of superior early and late patency. Many surgeons now commonly use both ITAs for CABG and many have adopted complex grafting methods such as free ITA graft and sequential anastomosis; despite these techniques, it's not always possible to achieve complete revascularization with arterial conduits. More recently the right gastroepiploic artery (rGEA) and the inferior epigastric artery (IEA) have been used as alternative arterial conduits. The authors report the experience of a case of myocardial revascularization in a patient with angina not responsive to medical therapy, severe tri-vessel coronary artery disease, which had a previous total bilateral saphenectomy; the patient was also found to have a right fibrothorax. In the surgical strategy the authors considered that the bilateral use of mammary artery could have been the cause of the depressed respiratory function and that it was important to leave intact the left hemithorax; they therefore employed the rITA in the revascularization of the anterior descending (AD). To complete the revascularization they used the IEA for a marginal branch of the circumflex artery and the rGEA for the interventricular posterior artery, branch of the right coronary artery. In this fashion good early results were obtained with absence of perioperative complications with a good life expectancy.

Coronary Angiography↗
PubMed1994

[Myocardial revascularization in aged patients: what is the surgical risk?].

There are still controversies about the surgical results of myocardial revascularization in aged population, in terms of cardiac and non-cardiac morbidity and mortality. This issue prompted us to study retrospectively 71 patients older than 75 years electively operated of coronary artery bypass grafting (CABG) from June 1990 to June 1993 (Group A). Elderly population was compared with a contemporaneous and concurrent control group of patients younger than 75 years (Group B). Patients > 75 years have been divided in successive subgroups according to the severity of coronary artery disease (3 vessel disease 67.7%, 2 vessel disease 26.7%, 1 vessel disease 5.6%), echocardiographic ejection fraction (EF > 50%: 40.8%; 50-30%: 42.2%; < 30%: 16.9%) and preoperative risk factors. Left internal thoracic artery (LITA) utilization rate was 97.1% in Group B and 57.7% in Group A (p < 0.001). Cardiopulmonary bypass circulation, aortic cross-clamping time and number of coronary anastomoses were similar in the 2 groups (2.87 +/- 0.9 versus 2.8 +/- 0.8, NS). Operative mortality rate of aged population was 4.2% while no patient of Group B died (NS). Concerning the cardiac morbidity, there were no significantly differences between the 2 groups: myocardial infarction occurred in 3 patients of Group B (4.2%) and in 5 patients of Group A (7%; NS). Atrioventricular block was also similar in the 2 groups. Non-cardiac complications occurred more frequently in the aged population group: neurologic complications in 11.2% versus 1.4% (p < 0.04), renal insufficiency in 12.6% versus 1.4% (p < 0.03) and respiratory failure in 9.8% versus 1.4% (p = 0.06). (ABSTRACT TRUNCATED AT 250 WORDS)

Age Factors↗