[Diagnostic and therapeutic observations drawn from the surgical experiences of 108 traumatic ruptures of the descending thoracic aorta]. / Observations diagnostiques et thérapeutiques tirées d'une expérience chirurgicale de 108 ruptures traumatiques de l'aorte thoracique descendante.

Traumatic rupture of the thoracic aorta should be suspected when automobile (62.9%), motorcycle (11.1%), ski-doo (2.7%), deltaplane (0.9%), or skiing accidents (0.9%), cause a sudden and rapid deceleration. It was also encountered with a vertical fall of 10 meters and more (4.6%), when a pedestrian was struck by a vehicle (4.6%) or the chest damaged by a high velocity flying object (4.6%). A lateral impact was found in 33% of injured patients and 52.7% were not wearing seat belts. Ruptured aorta was found as a single lesion in only 12% of the cases and among associated orthopedic lesions (63.8%) and abdominal injuries (28.7%), about 2/3 of them involved the left side of the body. The most reliable clinical sign of descending aortic rupture is the pseudo-coarctation syndrome found in 53% in the acute phase by simple pulse palpation and in 56% with blood pressure measurements. As soon as the diagnosis is suspected, associated hypertension present in 50% should be medically treated to avoid sudden exsanguination. Surgical repair should be undertaken with a perfusion technique which is an integral part of the ressuscitation procedure. A Gott shunt was used in 81 patients and a partial left heart bypass with a Bio-Medicus pump in 25 cases. This active atrioaortic bypass is physiologically superior. The pump flow (3727 +/- 612 ml/min.) is superior to the shunt flow (2833 +/- 576 ml/min.). Proximal pressure with the pump is better controlled (111 +/- 20 mmHg) than with the shunt (152 +/- 30 mmHg) and the mean distal pressure obtained with the pump is higher (81 +/- 19 mmHg) than with the shunt (64 +/- 22 mmHg). One case of paraplegia occured (0.9%) with an unfunctionnal Gott shunt. The survival rate is 95.4% (63/66 cases) in the acute phase and 100% (42/42 cases) in the chronic phase.

[Popliteal aneurysm: surgical treatment is mandatory before complications occur]. / L'anévrisme poplité: le traitement chirurgical s'impose avant l'apparition de complications.

Between 1972 and 1995, surgical repair was undertaken for 94 popliteal aneurysms diagnosed in 71 patients (69 men and 2 women) with a mean age of 66 years. Ninety-one femoropopliteal bypasses, 2 lumbar sympathectomies and one primary amputation were performed. Postoperative results of 28 elective bypasses performed for asymptomatic aneurysms (AA) were compared with 63 revascularisations needed for symptomatic aneurysms (SA) secondary to thrombosis (31%), embolization (30%), venous or nerve compression (13%), or rupture (2.1%). Occlusion of at least one tibial vessel was documented angiographically in 40% of the asymptomatic aneurysms and in 80% of the symptomatic aneurysms. No significant difference was observed between 5-year graft-patency of asymptomatic aneurysms (64%, mean followup 30 months +/- 37.2) and symptomatic aneurysms (50%, mean followup 39 months +/- 40.9). Furthermore, 5-year graft patency was not influenced by the number of patent tibial vessels in either of these populations. No statistically significant difference between these two groups was observed with respect to morbidity (AA: 10.7%, SA: 19%), or early reintervention (AA: 7.1%, SA: 9.5%). However, 12 secondary amputations were needed, all of which were performed after repair of a symptomatic aneurysm (19%, p < 0.05). No postoperative mortality was observed after an elective bypass while 3 patients (4.8%) with symptomatic aneurysms died after an emergency surgery. Ischemic symptoms persisted in 56% of patients who were initially symptomatic. Surgical correction should therefore be performed once the diagnosis of a popliteal aneurysm has been established in order to prevent amputation and late sequelae.

[Development of circulatory support during 420 aneurysm resections of the descending thoracic aorta]. / Evolution du support circulatoire au cours de 420 résections anévrismales de l'aorte thoracique descendante.

From July 1974 to January 1996, 420 aneurysms of the descending thoracic aorta were surgically treated at l'Hôpital du Sacré-Coeur de Montréal. Three principles were previously established and rigorously respected: 1) the preservation of distal body perfusion, 2) the briefest aortic cross-clamp time realizable (mean: 29.8 +/- 16 minutes overall, reduced to a mean of 24 +/- 6 minutes for the last 250 cases), 3) keep the aortic resection as short as possible in order to preserve as many intercostal arteries as possible (10 cm or less in 91.6% of the cases). In the first 380 cases, distal aortic circulation was supported with a 9 mm Gott shunt without using systemic heparinization. Average shunt flows from 300 ml/min, to 4900 ml/min. (mean: 2497 +/- 813 ml/min.), average proximal pressures from 80 to 200 mmHg (mean: 146 +/- 17 mmHg) and average distal pressures from 15 to 150 mmHg (mean: 64 +/- 19 mmHg) were recorded. In the last 40 cases, the distal circulation was supplied through the left heart assistance device Bio-Medicus using minimal systemic heparinization (0.5 mg/kg), (target ACT > 150 seconds). Average pump flows from 1800 ml/min to 5200 ml/min. (mean: 3340 +/- 866 ml/min.) were obtained. Average proximal pressures from 90 to 200 mmHg (mean: 118 +/- 19 mmHg) and average distal pressures from 58 to 180 mmHg (mean: 95 +/- 24 mmHg) were recorded. Overall hospital mortality is 11.9% (50/420 cases) and 9.9% when ruptured aneurysms are excluded. Paraplegia occurred in 2 patients (0.4%) and one was related to an unfunctional Gott shunt. Adverse anatomical conditions like a proximal aneurysm, degenerative changes of the aortic wall, a previous proximal graft replacement or the presence of coronary artery bypass grafts, a friable wall encountered with dissecting aneurysms and also an adverse physiological condition like a left ventricular dysfunction prompted us to modify the circulatory support by using the left heart bypass. Comparison of both methods of perfusion supported by statistical analysis regarding shunt and pump flows, proximal and distal perfusion pressures has showed the physiological superiority of the centrifugal pump that we have now routinely adopted.

The traumatized ischemic lower limb: a search for the optimal treatment.

OBJECTIVE: To improve the surgical results of closed injuries of the femoropopliteal arterial axis. DESIGN: A retrospective study over 20 years. SETTING: A university-affiliated hospital. PATIENTS: Fifty-nine patients (95% male, mean age 29 years) with 63 blunt injuries to the femoropopliteal arterial axis, treated by eight surgeons. INTERVENTIONS: Thrombectomy with saphenous vein patch arterioplasty; primary end-to-end anastomosis, saphenous vein interposition and saphenous vein bypass. MAIN OUTCOME MEASURES: Death rate, incidence and causes of amputation and late outcome of salvaged limbs. RESULTS: The death rate was 8.5%, the amputation rate was 25% and the long-term disability of salvaged limbs was 80%. Earlier ablation of two infected extremities and of another one responsible for acute renal failure would have reduced the death rate to 3% at the expense of increasing the amputation rate to 35%. The level of arterial disruption, the degree of soft-tissue damage and the ischemia time greatly influenced limb survival and long-term disability. The ischemia time is the single factor that can be modified by the medical team. If its duration is less than 15 hours, the amputation rate decreases. However, the ischemia time should be reduced to less than 7 hours to assure limb salvage without sequela. CONCLUSIONS: Early diagnosis and priority of the arterial repair over associated orthopedic injuries are essential to reduce the ischemia time. Despite successful revascularization, early amputation is the only means of saving life in some cases.

Aneurysms of the descending thoracic aorta: three hundred sixty-six consecutive cases resected without paraplegia.

PURPOSE: The aim of this study was to present a 20-year experience with a single method of passive distal perfusion during descending thoracic aortic aneurysm resection. METHODS: Aortic repair with a Dacron graft interposition was performed for 366 consecutive aneurysms located between the left subclavian artery and the crux of the diaphragm. The extent of aorta resected in 335 patients (91.5%) represented one third or less of the aortic length. A 9 mm Gott shunt was cannulated proximally into the ascending aorta (235 cases), the aortic arch (60 cases), the descending aorta (68 cases), or the left ventricle (3 cases) and inserted distally into the descending aorta (232 cases), the femoral artery (127 cases), or the abdominal aorta (7 cases). Shunt flows were recorded in 91 cases and varied from 1100 ml to 4900 ml/min, (mean 2526 ml/min). Distal pressure during shunting was measured in 62 patients. It varied from 15 to 120 mm Hg (mean 64.5 mm Hg). The aortic cross-clamp time varied from 8 to 124 minutes (mean 30 minutes). RESULTS: The hospital death rate was 12% overall and 9.9% (35/351) if ruptured aneurysms are excluded. Among 359 operating room survivors, neither immediate nor delayed ischemic spinal cord deficit occurred. Transient renal dysfunction occurred in nine patients (2.4%) and kidney failure in one (0.2%). Five deaths (1.3%) were shunt related. CONCLUSION: Distal perfusion with the 9 mm Gott shunt has proven to be an effective method to preserve spinal cord function. The limited extent of aorta resected and the brief aortic cross-clamp time may also be interactive factors of protection.

Descending thoracic aortic aneurysms: surgical treatment with the Gott shunt.

Over the past 16 years, 267 consecutive patients underwent surgery for a descending thoracic aortic aneurysm. To provide optimal protection of surrounding organs during aortic occlusion, a 9-mm Gott shunt was used for distal perfusion in all cases. The shunt was placed preferentially between the ascending aorta and the descending aorta; however, alternative sites of proximal and distal cannulation were chosen according to the location and the extent of the aneurysmal disease and the presence of a concomitant aneurysm along the aortic conduit. In one-third of the patients, a flowmeter on the shunt recorded shunt flows, which varied from 1100 mL/min to 4900 mL/min (mean 2526 mL/min). Because the highest shunt flows were obtained with proximal systolic pressures lower than 140 mm Hg, nitroglycerin and nitroprussate were used routinely to improve distal perfusion by arterial vasodilation and release of proximal organs from a circulatory overload. The mean aortic cross-clamp time was 33 minutes for the entire series but was reduced to 25 minutes for the last 140 patients. The hospital death rate was 14.6% overall (12.2% if ruptured aneurysms were excluded). Of the 267 patients, 260 survived the operation and underwent clinical neurologic assessment. No paraplegia or other spinal-cord ischemic deficit occurred.

[Traumatic tricuspid insufficiency with a right-to-left shunt and heart luxation]. / Insuffisance tricuspidienne traumatique avec shunt droit-gauche et luxation cardiaque.

Traumatic tricuspid insufficiency (TTI) with a right-to-left shunt through a patent foramen ovale associated with a cardiac herniation was identified in a 39-year-old man with severe hypoxemia. All reported cases of TTI with a right-to-left shunt are reviewed, the technical aspects of repair described and the physiologic mechanisms discussed.

Ambulatory mediastinoscopy and anterior mediastinotomy.

Ambulatory facilities are being used more and more for various diagnostic and therapeutic procedures. We report 158 consecutive mediastinoscopies and anterior mediastinotomies performed in an ambulatory setting from July 1981 to February 1990. There were 120 patients with a malignancy: 114 bronchogenic carcinomas, 4 lymphomas, 1 teratocarcinoma, and 1 carcinoma of the stomach. Thirty-eight patients had a benign condition, including sarcoidosis in 27 and miscellaneous diagnosis in 11. Twenty-two patients (14%) were admitted the same day: 9 for elective operation in view of bed availability, 8 for medical observation, and 5 for overnight admission for nonmedical reasons. Six nonfatal complications were encountered: hemoptysis (2), atrial fibrillation (1), pneumonia (1), mediastinal self-contained bleed (1), and tear of a pulmonary artery (1). There was no operative mortality. Overall, ambulatory mediastinoscopy and anterior mediastinotomy permitted a diagnosis in 47 patients (20%) and confirmed unresectable malignant disease in 29 patients, thus sparing unnecessary admission to a surgical ward in 76 (48%) of the 158 patients. Mediastinoscopy and anterior mediastinotomy can be safely performed in an ambulatory setting and do alleviate the need for hospitalization in a substantial number of patients.

Bronchial carcinoids: long-term prognostic factors.

Between 1962 and 1987 bronchial carcinoids were diagnosed in 41 patients (21 men, 20 women) at l'Hôpital du Sacré-Coeur and the Centre hospitalier Maisonneuve-Rosemont. The patients ranged in age from 19 to 73 years (mean 47 years). Fourteen of the 19 asymptomatic carcinoids were discovered on routine chest radiography. Twenty-two symptomatic patients presented with either pneumonia or hemoptysis. Tumours involved the right and left lungs equally. Thirty tumours were located centrally and 11 peripherally. Sensitivity of endoscopic biopsy specimens was 66%. No complications occurred during biopsy. Cytologic examination of sputum, lavage, brushing and transthoracic biopsy specimens was of no value in establishing the diagnosis. Thirty-seven patients underwent surgical resection: lobectomies (26, 3 with bronchoplasties), pneumonectomies (7), segmentectomies (2) and wedge resections (2). One patient (3%) died, and there was one major complication (3%) related to surgery. The mean follow-up was 8 years. The probability of survival was 97% +/- 3 at 5 years and 92% +/- 6 at 10 years. None of the 19 patients treated for a peripheral tumour died, but two patients who had centrally located tumours that exhibited transbronchial invasion and lymph-node metastasis died. No prognostic information could be gained from tumour size or type. A statistical association was found between transbronchial invasion and lymph-node metastasis. Bronchial carcinoids are low-grade malignant tumours. Resection should be conservative, but lymph-node involvement requires a more radical approach.

[Thoracotomy with muscle sparing]. / La thoracotomie avec épargne musculaire.

Muscle sparing thoracotomy is suggested more frequently in recent literature. From March 1988 to February 1990, a muscle sparing technique was used in 77 (58%) of 132 consecutive thoracotomies. There were 50 men and 27 women, age varied from 23 to 81 years, with a mean of 58 years. Forty-four lobectomies, 10 pneumonectomies, 9 lung biopsies, 6 wedge resections, 6 bullectomies and 2 segmentectomies were performed. A horizontal incision was used in 47 (61%) patients and a vertical mid-axillary incision in 30 (39%). For optimal exposure, transection of the latissimus dorsi muscle was needed in 14 (30%) of the horizontal incisions. Inadvertent rib fracture occurred in 10 (13%) cases. Continuous epidural analgesia was added in 46 (60%) patients for an average of 40 hours. Mechanical ventilation in 14 (18%) patients for a mean duration of 22 hours and an average stay of 2 days in the ICU and 7 days in the hospital, were required. There was 1 (1.3%) hospital mortality, 4 (5%) patients developed a seroma that required aspiration. Muscle sparing thoracotomy can be used safely for most thoracic procedures and we believe it permits easier pain control and early preservation of full shoulder motion. However the operative field is more restricted. A horizontal incision, permitting section of the latissimus dorsi for better exposure should be used for hilar or invasive lesions.

[Mediastinoscopy in ambulatory surgery: nine years' experience]. / Médiastinoscopie en chirurgie ambulatoire: neuf années d'expérience.

Ambulatory facilities are being used more and more for various diagnostic and therapeutic procedures. We report 183 consecutive mediastinoscopies and/or anterior mediastinotomies performed in an ambulatory setting from July 1981 to January 1991. There were 140 patients with a neoplasia: 131 bronchogenic carcinomas, 5 lymphomas, 2 carcinoid tumors, 1 teratocarcinoma, 1 carcinoma of the stomach. Forty-three patients had a benign condition, including 32 sarcoidosis and 11 miscellaneous diseases. Twenty-eight (15%) patients were admitted the same day: 12 for elective surgery in view of bed availability, 9 for medical observation, and 7 required overnight admission for non-medical reasons. Eight non-fatal complications were encountered: hemoptysis (2), atrial fibrillation (1), pneumonia (1), mediastinal self-contained bleed (1), tear of a pulmonary artery (1), temporary palsy of the recurrent laryngeal nerve (1) and wound infection (1). There was no operative mortality. Overall, ambulatory mediastinoscopy and anterior mediastinotomy permitted a diagnosis in 58 patients (29%), and confirmed unresectable malignant disease in 36 patients, thus sparing unnecessary admission to a surgical ward in 89 (49%) of the 183 patients. Mediastinoscopy and anterior mediastinotomy are safe in an ambulatory setting and alleviate the need for hospitalization in a substantial number of patients.

[Use of the Gott shunt in the prosthetic replacement of the aortic arch]. / Utilisation du shunt de Gott lors de remplacement prothétique de la crosse aortique.

Our previous experience in 272 consecutive cases of descending thoracic aortic aneurysms resected without paraplegia by using the 9 mm Gott shunt encouraged us to apply the same technique to more complex aortic surgery. Graft replacement of the transverse aortic arch with brachio-cephalic vessel reattachment was undertaken in 2 patients without the aid of extracorporeal circulation and without systemic heparinisation. Body perfusion was achieved with two 9 mm Gott shunts inserted between the ascending aorta and both femoral arteries. A 10 mm graft interposition between the shunts and the femoral arteries allowed for retrograde perfusion and distal leg irrigation. Blood supply to the brain was maintained with the cut halves of a 7 mm Gott shunt connected as side branches to one of the 9 mm shunts, allowing cannulation of the innominate ant the left carotid arteries. In 90 of the 272 patients treated for a descending aortic aneurysm, a mean shunt flow of 2526 ml/min. was recorded through the 9 mm Gott shunt and from there, we took for granted that the total cardiac output, in there 2 patients, could be propelled by using 2 shunts. During aortic cross clamping, there were no change in the filling pressure of either the right heart or the left heart, and no metabolic acidosis was observed. Both patients survived with normal physiological function of all organs including the brain and the spinal cord.

Thromboembolism from undersized Dacron grafts in the descending thoracic aorta.

Three patients were referred to our institution for major thromboembolic complications secondary to the use of undersized Dacron grafts (14, 16, and 18 mm) in the descending thoracic aorta. The progressive accumulation of thrombotic material in the prosthesis caused recurrent coarctation in 1 patient and peripheral embolisms in the other 2. With a 9-mm Gott shunt providing distal perfusion, excision of the clotted graft and its replacement with a 22-mm Dacron prosthesis was successfully achieved in each patient.

Intrapericardial trauma: surgical experience.

From 1975 to 1987, 19 patients (pts) were operated on for a traumatic lesion of the heart or of the ascending aorta. There were 15 males and four females with a mean age of 42 years. Twelve lesions (Group I) were penetrating and seven (Group II) blunt. Group I: Nine patients were in shock upon admission, including six with cardiac tamponade. Six pts were stabbed, three sustained a gunshot wound, and two were accidental victims of a pneumatic gun. In the last pt, with previous lung surgery and mediastinal shift, a chest tube lacerated the right ventricle; this pt died in the operating room (OR), for a mortality rate of 8.3% (1/12). Associated intrathoracic and intra-abdominal lesions were present, but did not influence the outcome. Group II: All pts were involved in motor vehicle accidents. Five pts were in shock, including two with cardiac tamponade. Three pts required extracorporeal circulation (ECC) for aortic valve replacement, tricuspid valve reconstruction, and replacement of the ascending aorta. In one case, a lacerated right ventricle could be repaired without ECC, but the pt died from low cardiac output. Three pts with a ruptured left ventricle were managed in the OR, and two pts exsanguinated for a mortality rate of 43% (3/7). Associated lesions were present and death was related to ventricular rupture. Intrapericardial lesions are relatively rare in our Canadian experience. High survival can be obtained in penetrating injuries, while blunt injuries are more complex and remain highly lethal. ECC should be available for definitive treatment.

Surgery of the descending thoracic aorta: spinal cord protection with the Gott shunt.

From July, 1974, to July, 1987, surgical treatment of descending thoracic aortic aneurysms was performed in 173 patients at l'Hôpital du Sacré-Coeur de Montréal. The cause of the aneurysms was arteriosclerosis or medial degeneration in 83 patients, trauma in 50, dissection in 34, and a congenital malformation in 6. A single method of external shunting provided distal perfusion in all patients in the series. A 9-mm Gott aneurysm shunt was placed preferentially between the ascending aorta (67%) and the descending aorta (60%). Alternative sites of proximal cannulation (aortic arch, 9%; proximal descending aorta, 22%; left ventricle, 2%) and distal cannulation (abdominal aorta, 3%; left femoral artery, 37%) were chosen based on the location and the extent of the aortic aneurysm. No systemic heparinization was used. In the last 40 patients, a flowmeter adapted for use with the shunt allowed the recording of shunt flow (mean, 2,475 ml/min; range, 1,100 to 4,000 ml/min). Hospital mortality, including patients with ruptured aneurysms, was 15% (26/173). The mean aortic cross-clamp time was 37 minutes (range, 8 to 105 minutes). Of the 173 patients, 168 survived long enough to allow accurate clinical evaluation of the function of the spinal cord: no paraplegia or other spinal cord ischemic injury occurred. To date, our clinical experience has demonstrated the effectiveness of the 9-mm Gott shunt in preserving the functional integrity of the spinal cord during cross-clamping of the thoracic aorta.