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A phase III randomized trial of postoperative pelvic irradiation in Stage IB cervical carcinoma with poor prognostic features: follow-up of a gynecologic oncology group study.

PURPOSE: To investigate, in a phase III randomized trial, whether postoperative external-beam irradiation to the standard pelvic field improves the recurrence-free interval and overall survival (OS) in women with Stage IB cervical cancers with negative lymph nodes and certain poor prognostic features treated by radical hysterectomy and pelvic lymphadenectomy. METHODS AND MATERIALS: Eligible patients had Stage IB cervical cancer with negative lymph nodes but with 2 or more of the following features: more than one third (deep) stromal invasion, capillary lymphatic space involvement, and tumor diameter of 4 cm or more. The study group included 277 patients: 137 randomized to pelvic irradiation (RT) and 140 randomized to observation (OBS). The planned pelvic dose was from 46 Gy in 23 fractions to 50.4 Gy in 28 fractions. RESULTS: Of the 67 recurrences, 24 were in the RT arm and 43 were in the OBS arm. The RT arm showed a statistically significant (46%) reduction in risk of recurrence (hazard ratio [HR] = 0.54, 90% confidence interval [CI] = 0.35 to 0.81, p = 0.007) and a statistically significant reduction in risk of progression or death (HR = 0.58, 90% CI = 0.40 to 0.85, p = 0.009). With RT, 8.8% of patients (3 of 34) with adenosquamous or adenocarcinoma tumors recurred vs. 44.0% (11 of 25) in OBS. Fewer recurrences were seen with RT in patients with adenocarcinoma or adenosquamous histologies relative to others (HR for RT by histology interaction = 0.23, 90% CI = 0.07 to 0.74, p = 0.019). After an extensive follow-up period, 67 deaths have occurred: 27 RT patients and 40 OBS patients. The improvement in overall survival (HR = 0.70, 90% CI = 0.45 to 1.05, p = 0.074) with RT did not reach statistical significance. CONCLUSIONS: Pelvic radiotherapy after radical surgery significantly reduces the risk of recurrence and prolongs progression-free survival in women with Stage IB cervical cancer. RT appears to be particularly beneficial for patients with adenocarcinoma or adenosquamous histologies. Circumstances that may have influenced the overall survival differences are considered.

Adenocarcinoma↗

Surgery offers no more than medical treatment in the management of transient ischaemic attack.

This paper debates the motion that 'Surgery offers no more than medical treatment in the management of transient ischaemic attack' (TIA). The arguments in support of this motion are that surgical treatment has a high morbidity and mortality, and that even the investigation of patients by angiography prior to surgery entails a risk of stroke; that TIA is a marker of generalised vascular disease, and that medical treatment can reduce the incidence of stroke after TIA. The counter arguments are that TIA is associated with an increased risk of stroke and this risk can be reduced by surgery; that recent surgical results show an acceptable complication rate, and that modern methods of investigation permit accurate non-invasive assessment of patients at risk of stroke.

Aspirin↗

Randomised clinical trial of physiotherapy after open abdominal surgery in high risk patients.

Postoperative physiotherapy has been shown to reduce the incidence of postoperative pulmonary complications after open abdominal surgery. This study aimed to determine if the addition of deep breathing exercises and secretion clearing techniques to a standardised physiotherapist-directed program of early mobilisation improved clinical outcomes in patients undergoing open abdominal surgery. Fifty-six patients undergoing open abdominal surgery, at high risk of developing postoperative pulmonary complications, were randomised before operation to an early mobilisation-only group or an early mobilisation-plus-deep breathing and coughing group. Mobility duration, frequency and intensity of breathing interventions were quantified for both groups. All outcomes were assessed by a blinded outcomes researcher using a standardised outcomes measurement tool developed specifically for this population. Outcomes included incidence of clinically significant postoperative pulmonary complications, fever, length of stay, and restoration of mobility. There were no significant differences between groups in mean age, anaesthetic time, perioperative morbidity, or postoperative mobility. Outcome data were available for 89% of enrolled subjects. Overall incidence of postoperative pulmonary complications was 16%. The incidence of postoperative pulmonary complications in the non-deep breathing and coughing group was 14%, and the incidence of postoperative pulmonary complications in the deep breathing and coughing group was 17%, (absolute risk reduction -3%, 95% C1 -22 to 19%). There was no significant difference between groups in the incidence of fever, physiotherapist time, or the number of treatments. This study suggests that, in this clinical setting, the addition of deep breathing and coughing exercises to a physiotherapist-directed program of early mobilisation does not significantly reduce the incidence of clinically significant postoperative pulmonary complications in high risk open abdominal surgery subjects.

Abdomen↗

Perioperative total parenteral nutrition in malnourished, gastrointestinal cancer patients: a randomized, clinical trial.

BACKGROUND: Clinical trials investigating the potential benefits of perioperative total parenteral nutrition (TPN) for reducing the risk of surgery in malnourished cancer patients have yielded controversial results. METHODS: Ninety elective surgical patients with gastric or colorectal tumors and weight loss of 10% or more of usual body weight were randomly assigned to 10 days of preoperative and 9 days of postoperative nutrition vs a simple control group. The daily per kilogram body weight TPN regimen included 34.6 +/- 6.3 kcal nonprotein and 0.25 +/- 0.04 g nitrogen per kilogram in a volume of 42.6 +/- 7.3 mL of fluid. The glucose-to-fat calorie ratio was 70:30. Control patients did not receive preoperative nutrition but received 940 kcal nonprotein plus 85 g amino acids postoperatively. RESULTS: Complications occurred in 37% of the patients receiving TPN vs 57% of the control patients (p = .03). Noninfectious complications mainly accounted for this difference, which was 12% vs 34%, respectively (p = .02). Mortality occurred in only 5 of the control group patients (p = .05). The total length of hospitalization for TPN patients was longer than for control (p = .00), whereas the length of postoperative stay in the two groups did not differ significantly. CONCLUSIONS: This study shows that 10 days of preoperative TPN that is continued postoperatively is able to reduce the complication rate by approximately one third and to prevent mortality in severely malnourished patients with gastrointestinal cancer.

Aged↗

Radiotherapy of breast cancer after breast-conserving surgery: an improved technique using mixed electron-photon beams with a multileaf collimator.

BACKGROUND AND PURPOSE: Loco-regional radiotherapy after breast cancer surgery significantly reduces the risk of recurrences. An increase of cardiac deaths for irradiated breast cancer patients has been reported in some studies, especially for women with tumours in the left breast. The aim of this study was to compare retrospectively the conventionally used technique using two opposed tangential photon beams with a modified technique using a combination of photon and electron beams to find an optimal technique with respect to dose homogeneity in the breast and surrounding regional lymph nodes and a minimal dose in the organs at risk. MATERIALS AND METHODS: Thirty patients with stage II breast cancer who received different types of adjuvant systemic therapy were included in the investigation. Comparative dose planning of two techniques was performed, i.e. an isocentric technique with two photon beams with coplanar medial beam edges and a technique with one electron and three photon beams with a common isocentre for all beams aided by a multileaf collimator. RESULTS: The mixed technique was selected for eight of 12 patients with left-sided breast cancers because of significantly lower doses to the heart. However, the decision-making was influenced by many factors such as dose coverage of the target volume combined with minimizing of the doses to the organs at risk and the contralateral breast. CONCLUSION: The use of the mixed technique will optimize the loco-regional radiotherapy after breast-conserving surgery for many left-sided breast cancers.

Adult↗

[Surgery in the cirrhotic patient. Prognosis and risk factors].

Patients with cirrhosis have reduced life expectancy. Surgery is often associated with clinical decompensation in this group of patients. The purpose of this paper is to study the surgical risk in cirrhotic patients undergoing nonderivative operations. Unfortunately, most of the studies in the literature about this problem are retrospective reviews with limitations. The conditions increasing surgical risk in cirrhotic patients are analysed. These include changes in the pharmacokinetics and pharmacodynamics of various drugs, altered hemostasis, poor resistance to infections, water retention, suture line insufficiency, chronic renal failure and congestive heart failure. Assessment of the disease stage in cirrhosis is very important, because the severity of hepatic abnormalities influences the prognosis. The Child-Pugh classification has been used extensively to risk-stratify patients with cirrhosis. However, the disregard for cardiorespiratory, renal, electrolyte balance and acid-base status limits its predictive accuracy. Recently a new scoring system, the Acute Physiology and Chronic Health Evaluation (APACHE III), has been introduced and seems to be superior to Child-Pugh for prognosticating short term survival of cirrhotic patients. In conclusion, surgery can be done safely only in cirrhotic patients with a good hepatic function. On the contrary, in patients with advanced cirrhosis, surgery causes a very high mortality. Finally, the patients with moderate hepatic failure can be operated only after a careful study of the disease and an adequate correction of the reversible risk factors.

Blood Coagulation↗

A pilot study of blood antioxidant and free radical marker profiles in patients awaiting coronary artery bypass grafting.

Coronary artery bypass grafting (CABG) carries a high risk of acute pancreatitis. We report a pilot study to investigate whether pre-existing oxidative stress might underlie this susceptibility, in that a burst of free radical activity not only accompanies the reperfusion stage of CABG but seems to be a pivotal step in the pathogenesis of pancreatitis. Samples of peripheral venous blood were obtained on the morning of surgery from 8 consecutive patients (age, median and range, 62, 35-70 years) with > 75% stenosis in at least three coronary vessels and a further 8 (64, 49-70 years) who had received 1200 mg allopurinol in divided doses in the previous 48 h: the results were compared with profiles of 8 healthy controls (56, 50-60 years) with normal exercise ECG. None of the patients or controls currently smoked cigarettes and the majority drank alcohol on a social basis. Compared with controls, untreated patients had lower levels of glutathione (P < 0.001) and ascorbate (P < 0.05) in plasma, alpha-tocopherol (vitamin E as molar ratio of cholesterol, P < 0.025 and beta-carotene (P < 0.05) in serum. There was no difference in serum selenium levels, but values in patients and controls were lower than in younger controls from this area (P < 0.02). Samples from the patients contained higher concentrations of lipid peroxides than control samples (P < 0.25) but there was no evidence of excessive isomerisation of linoleic acid or oxidation of ascorbate and erythrocytes showed normal ATP and energy charge with no increase in membrane lipid peroxidisability. Treatment with allopurinol did not alter this pattern, such that the ratio of oxidised to total glutathione in plasma was higher among the 16 patients than 8 controls (P < 0.025). Habitually inadequate intakes are the best explanation for the patients' deficits in aqueous phase antioxidants; prescribed low cholesterol diets would exacerbate any prior insufficiency of lipid-phase antioxidants. Correction of these deficits during the months leading up to surgery should reduce the risk of CABG-induced acute pancreatitis.

Adult↗

Bilateral supraorbital keyhole approach for multiple aneurysms via superciliary skin incisions.

BACKGROUND: Considering that multiple aneurysms carry a high risk for fatal rupture, there is a need for complete treatment of all lesions in one surgical session using either unilateral-contralateral or bilateral approaches. Contralateral approaches have been used mainly for small anteriorly projecting middle cerebral and medially expanding ophthalmic types of aneurysms. They are limited by the narrow space for surgical manipulation, forced elevation of frontal lobes, and stretching of the olfactory nerves. These problems might result in damage to structures along the unusually long intracranial way of the approach. The complications associated with the unnecessarily large conventional fronto-temporal and bifrontal craniotomies, and the developments in visualization, neuroanaesthesia, microneurosurgery, cerebrospinal fluid (CSF) drainage, and brain protection have led to less invasive methods in cerebral base surgery. These achievements have supplied the background for the supraorbital keyhole approach to aneurysms of the anterior circulation or basilar tip. Because the supraorbital keyhole approach offers several advantages over the classic fronto-temporal craniotomies to the anterior skull base, it was extended for both sides in one surgical session to treat bilateral multiple aneurysms as well. METHODS: Out of a series of 150 patients harboring 188 saccular aneurysms operated on via a supraorbital keyhole approach with a superciliar skin incision, 36 had multiple aneurysms. Thirty patients with multiple aneurysms underwent surgery for their ruptured aneurysms (17 cases in the acute phase and 13 patients during the chronic stage); in 6 cases silent aneurysms were operated on. The multiple aneurysms were managed from one side in 18 cases. A bilateral supraorbital keyhole approach was performed during one surgical session in 11 patients, and in 7 cases the unilateral supraorbital keyhole approach was combined with contralateral fronto-temporal (3 cases), suboccipital (2 cases), or frontal-parasagittal (2 cases) exploration. The operations were carried out through an approximately 2.5 x 3 cm supraorbital keyhole craniotomy following a skin incision just above the eyebrow. The roughly 4 cm superciliar skin incision begins medial to the supraorbital nerve and ends 3 to 10 mm beyond the lateral edge of the eyebrow. The technical details of the method are presented, and the benefits, limitations, and complications are discussed. RESULTS: In the 36 patients operated on via the supraorbital keyhole approach 74 aneurysms were clipped successfully. In 2 cases premature intraoperative rupture of the aneurysms occurred, but these events were managed successfully. Despite the small size of the craniotomy the approach allows enough room for intracranial manipulation with maximal protection of the brain and other intracranial structures. One patient died because of pulmonary embolism. There were no craniotomy-related complications in the present series. CONCLUSION: The supraorbital keyhole approach together with the advent of the modern neuroanaesthesia, CSF drainage, and microsurgical techniques is a safe approach in the hands of experienced neurosurgeons for the treatment of supratentorial or basilar tip aneurysms. Because the approach is simple and swift, the bilateral single-session craniotomy does not have any disadvantages compared to two-stage procedures. However, the one-sitting surgery reduces the high risk of fatal rupture in the perioperative period associated with multiple aneurysms.

Cerebral Angiography↗

Ductal lavage in patients undergoing mastectomy for mammary carcinoma: a correlative study.

BACKGROUND: Ductal lavage (DL) is a new method for the sampling of breast epithelium. Data regarding its sensitivity in the detection of epithelial abnormalities, including carcinoma in situ (CIS), remains limited. METHODS: DL was performed in the affected breasts of 26 women undergoing mastectomy for mammary carcinoma and in the clinically normal breast of 4 additional women undergoing risk-reducing mastectomy. After surgery, dye was injected through the microcatheter used for DL. Three cytopathologists independently reviewed all DL slides and the data reflect consensus by at least two reviewers. Interobserver agreement was assessed. The findings in DL samples were correlated with the features of CIS in the mastectomy specimens. RESULTS: Four (14%) of 29 DL samples satisfactory for evaluation showed marked atypia, 10 (34%) showed mild atypia, and 15 (52%) were benign. No DL sample was clearly malignant. Interobserver agreement was good (average kappa = 0.52). Of the DL samples satisfactory for evaluation, 27 had been obtained from 24 breasts containing CIS, which included 18 ductal CIS (DCIS), 3 lobular CIS (LCIS), 2 DCIS and LCIS, and 1 solid CIS with mixed ductal and lobular features. Invasive carcinoma was present in 20 samples. Two DL samples from breasts with extensive LCIS showed mild atypia and injected dye was identified in ducts and lobules involved by LCIS. CONCLUSIONS: DL had low sensitivity for CIS in breasts that also contained invasive carcinoma. The use of DL remains investigational, and close follow-up should be continued for all patients undergoing DL, including those with benign diagnoses.

Adult↗

Osteosynthesis of injuries and rheumatic or congenital instabilities of the upper cervical spine using double-threaded screws.

The surgical treatment of instabilities of the upper cervical spine, independent of their cause, requires the use of differentiated procedures if functional anatomy is to be largely restored. Successful procedures have been the diagonal screw fixation of the axis from the anterolateral aspect in case of acute fractures of the odontoid process, transpedicular screw osteosynthesis of C2 in hangman's fractures with bony instability, and the transarticular screw fixation of C 1/2 with interarcual fusion for atlantoaxial instabilities. Compared with conventional screws, the use of double-threaded screws which are almost totally imbedded in the vertebral body has the advantage of eliminating local irritation, reducing the risk of surgery, and simplifying the operative procedure itself.

Bone Screws↗

A Retrospective Study of Breast Cancer Patients Treated with Quadrantectomy without Radiation Therapy.

BACKGROUND: Radiation therapy after breast-conserving surgery (BCS) reduces the risk of local recurrence. However, whether radiation therapy is necessary forall patients undergoing BCS remains unclear. METHODS: In order to determine the selection criteria for patients who can safely omit radiation therapy and to confirm the survival benefit of quadrantectomy without radiation therapy, we reviewed 107 patients who underwent quadrantectomy without radiation therapy between February 1988 and July 1995. RESULTS: The 5-year overall survival, disease-free survival and cumulative local recurrence rates were 93.7%, 80.7% and 12.1% respectively. There were no significant differences of 5-year overall survival (94.0% vs 94.1%) and disease-free survival rates (83.1% vs 70.0%) between patients with or without tamoxifen. The 5-year cumulative local recurrence rate of patients with tamoxifen, however, tended to be lower (p = 0.0810) than that of patients without tamoxifen. The 5-year cumulative local recurrence rate of the patients aged 45 or less was significantly higher than that of patients aged from 45 to 55 years and those over 55 (p= 0.0090 and 0.0089, respectively). In ER positive patients, the 5-year cumulative local recurrence rate of patients with tamoxifen tended to be lower (p= 0.0791) than that of patients without tamoxifen. CONCLUSION: The survival rate of quadrantectomy without radiation therapy wasacceptable. While the risk of local recurrence following quadrantectomy withoutradiation therapy is substantial, radiation therapy following quadrantectomy might not be necessary in elderly ER positive women receiving adjuvant tamoxifen therapy.

Journal Article↗

Coagulation modifications after laparoscopic and open cholecystectomy in a swine model.

BACKGROUND: The stress response to surgical trauma precipitates a state of transient hypercoagulation. Studies have demonstrated that laparoscopic surgery results in a diminished stress response compared to open surgery. The aim of this study was to determine the extent of postoperative hypercoagulability following laparoscopic cholecystectomy (LC) compared to open cholecystectomy (OC). METHODS: Twenty-one pigs were randomly selected to undergo LC (N = 10) or OC (N = 11). Whole blood was collected preoperatively and on postoperative days (PODs) 1, 2, and 3 for determination of viscoelastic changes using a thromboelastography (TEG) coagulation analyzer. Four parameters were calculated from the TEG: R (reaction time), K (coagulation time), alpha (rate of clot formation), and MA (maximal amplitude). Antithrombin III (AT III) level was measured preoperatively and on POD 1. RESULTS: After OC, three of four TEG parameters changed to reflect a state of hypercoagulation. Only MA values were significantly changed after LC. Comparison between OC and LC showed no difference in the TEG parameter. There was no significant change in AT III levels after LC or OC. CONCLUSIONS: OC results in postoperative hypercoagulation typically encountered in open abdominal surgery. Although there were no differences in TEG or AT III between the two groups, after the laparoscopic approach all but one TEG parameter remained unchanged, suggesting a diminished hypercoagulable state. By reducing postoperative hypercoagulation, laparoscopic surgery may reduce the risk of developing postoperative venous thrombosis.

Animals↗

Descending or thoracoabdominal aortic aneurysm repair without intercostal vessel reconstruction using contrast magnetic resonance angiography: report of two cases.

Two high-risk patients underwent a graft replacement for descending thoracic or thoracoabdominal aortic aneurysms without the reconstruction of any intercostal and lumbar arteries. The first patient was an 81-year-old woman with asthma and renal dysfunction who was diagnosed to have a descending thoracic aortic aneurysm extending from the Th8 to Th12 level. Contrast magnetic resonance angiography (MRA) demonstrated the Adamkiewicz artery to originate from the left second lumbar artery. The second patient was a 59-year-old man with left ventricular dysfunction due to aortic and mitral stenoses who was diagnosed to have a Crawford type IV thoracoabdominal aortic aneurysm. Contrast MRA showed the Adamkiewicz artery to originate from the left ninth intercostal artery. In general, the reestablishment of the spinal cord's blood supply, whenever possible, is generally considered to be necessary in such patients to prevent spinal cord injury. However, the reimplantation of intercostal vessels is the most complex aspect of this surgical modality, and therefore, it may cause a substantial increase in the cardiopulmonary bypass time. However, at least in some cases, such as the two cases presented herein, the use of contrast MRA was found to reduce the risk in surgery for descending thoracic or thoracoabdominal aortic aneurysms by eliminating the need for any intraoperative management of the intercostal and lumbar arteries.

Aged↗

A joint protocol for the neurosurgical and neuroradiologic treatment of cerebral arteriovenous malformations: indications, technique, and results in 76 cases.

We report on a group of 76 patients who had been treated during a period in which preoperative embolization using interventional neuroradiologic technique was standard procedure. During this time, 20 consecutive patients were operated on without embolization, eight patients were treated with embolization only, and 48 patients were operated on after embolization. In 35 cases surgery immediately followed the last embolization procedure. All arteriovenous malformations (AVMs) were classified and the outcome analyzed according to Spetzler [J Neurosurg 1986; 65: 476-83]. Those lesions treated with a combination of embolization and surgery had higher Spetzler grading than those that had been operated without previous embolization. The overall recovery rate was 82.9%. In 7.9% of the cases the AVMs were not totally extirpated. The overall complication rate was 9.2%. It is concluded that preoperative embolization facilitates surgery and reduces the risk of severe morbidity and mortality, especially in high-grade lesions. In addition to the clinical results, the application and usefulness of Ethibloc as an embolizing agent is reported.

Adolescent↗

Impact of intravenous magnesium on post-cardiothoracic surgery atrial fibrillation and length of hospital stay: a meta-analysis.

Postoperative atrial fibrillation can occur in 25% to 40% of patients undergoing cardiothoracic surgery. Although the majority of postoperative atrial fibrillation is benign, it has been associated with prolonged hospital length of stay. Magnesium prophylaxis against postoperative atrial fibrillation has been evaluated in several clinical trials; however these trials were small in size and therefore conveyed mixed or inconclusive results. In an attempt to better understand magnesium's role in this setting, we conducted a meta-analysis. A systematic literature search was conducted from January 1999 through August 2004 to identify trials of prophylactic magnesium in the setting of cardiothoracic surgery. The primary outcome measure was the incidence of postoperative atrial fibrillation. Trials were further analyzed based on cumulative doses of magnesium and perioperative time of initiation of prophylaxis, as well as length of stay. Seven randomized trials were identified. Upon meta-analysis, magnesium was found to prevent postoperative atrial fibrillation with an odds ratio of 0.66 and 95% confidence interval of 0.51 to 0.87. The incidence of postoperative atrial fibrillation was also significantly reduced in the low dose with an odds ratio of 0.36 and 95% confidence interval of 0.23 to 0.56, and in the preoperative groups with an odds ratio of 0.46 and 95% confidence interval of 0.31 to 0.67. Prophylactic magnesium reduced length of stay (n = 6 studies) by a weighted mean difference of 0.29 days, with a 95% confidence interval 0.54 to 0.05. Prophylactic magnesium reduced cardiothoracic surgery patients' risk of postoperative atrial fibrillation and length of stay. Administering lower doses and initiating prophylaxis in the preoperative period achieved the greatest reduction in postoperative atrial fibrillation.

Atrial Fibrillation↗

Contrasting effects of varicose vein surgery on endothelial-dependent and -independent cutaneous vasodilation in the perimalleolar region.

OBJECTIVES: To evaluate the effects of varicose vein surgery on cutaneous microvascular perfusion and vasodilator responses to acetylcholine (Ach) and sodium nitroprusside (SNP) in the gaiter area of patients with great saphenous vein insufficiency. METHODS: Twenty-nine patients with isolated great saphenous vein incompetence attended three study mornings (before surgery, and 6-8 weeks and 6 months after sapheno-femoral ligation+partial stripping) during which cutaneous microvascular responses were measured in the supine and standing positions using laser Doppler fluximetry (LDF) combined with incremental-dose iontophoretic administration of endothelial-dependent (Ach) and -independent (SNP) vasodilators. RESULTS: Varicose vein surgery had no significant effect on baseline cutaneous perfusion or the microvascular response to Ach: e.g. peak vasodilator responses to the 1000 microC stimulus were mean 58 SEM 7, 64 SEM 6 and 65 SEM 7PU on the pre-operative, 6-8 weeks and 6 months assessments. In contrast, the corresponding responses to SNP were significantly increased following surgery: e.g. at 2000 microC, mean 63 SEM 9, 142 SEM 4 and 157 SEM 9PU (p<0.0001) in the upright position. CONCLUSIONS: Sapheno-femoral ligation and partial stripping in patients with great saphenous vein insufficiency improves endothelial-independent cutaneous vasodilator function at the gaiter area, which may at least partly explain the benefits of surgery in reducing the risk of venous ulceration.

Acetylcholine↗

A cost-effectiveness model for coronary thrombolysis/reperfusion therapy.

A model was designed to examine the relations between incremental costs and benefits of coronary thrombolysis/reperfusion therapy. The model allows for the study of intravenous and intracoronary streptokinase, intravenous tissue plasminogen activator and primary angioplasty. Three strategies for the management of reocclusion are also compared. It was found that each of the following four variables can be responsible for a 2- to 15-fold variation in the costs per additional survivor: 1) the quantity of jeopardized myocardium, 2) the duration of coronary occlusion before the onset of therapy, 3) the time required from the onset of therapy until reperfusion is achieved, and 4) the reocclusion management strategy. Therapeutic strategies involving intravenous administration of thrombolytic agents were found to be consistently more cost effective than were strategies involving intracoronary administration of thrombolytic agents and primary angioplasty. In patients with a large or moderate-sized infarct, proper selection of intravenous protocols and reocclusion management strategies leads to costs of $7,000 to $100,000/additional survivor, costs that are similar to those of many generally accepted medical practices. Substantially higher costs per additional survivor are incurred with the routine use of thrombolytic therapy in patients with a small infarct or the routine use of coronary artery bypass surgery to reduce the risk of reocclusion after successful thrombolytic therapy. Decisions regarding which patients should receive thrombolysis/reperfusion therapy depend on society's willingness to pay for its incremental benefits.

Angioplasty, Balloon↗