Aortic reconstruction in high-risk pulmonary patients

Peri-operative physiotherapy

Postoperative pulmonary complications (PPC) are a major cause of morbidity, mortality, prolonged hospital stay, and increased cost of care. Physiotherapy (PT) programs in post-surgical and critical area patients are aimed to reduce the risks of PPC due to long-term bed-rest, to improve the patient's quality of life and residual function, and to avoid new hospitalizations. At this purpose, PT programs apply advanced cost-effective therapeutic modalities to decrease complications and patient's ventilator-dependency. Strategies to reduce PPC include monitoring and reduction of risk factors, improving preoperative status, patient education, smoking cessation, intra-operative and postoperative pulmonary care. Different PT techniques, as a part of the comprehensive management of patients undergoing cardiac, upper abdominal, and thoracic surgery, may prevent and treat PPC such as secretion retention, atelectasis, and pneumonia.

Physiotherapy in the perioperative period

Surgery and general anaesthesia have direct effects on the respiratory system depending on the organ/system involved and modality of delivery, potentially leading to postoperative pulmonary complications that increase hospital morbidity, prolong hospital stay and add to health-care costs. Postoperative complications have been reported to be as high as 30% for thoracotomy and lung resection in patients with chronic obstructive pulmonary disease. Most of the complications are due to respiratory muscle dysfunction and surgery-related changes in chest wall mechanics. In general, preoperative optimisation of medical therapy combined with physiotherapy and early extubation and mobilisation may improve clinical outcomes in high-risk surgeries, including upper abdominal and thoracic surgery in patients with severe emphysema. Evidence from randomised controlled trials or meta-analyses is limited and most of the recommendations on perioperative physiotherapy come from either uncontrolled or non-randomised trials or from observational studies and expert opinion.

Predictors of severe morbidity and death after elective abdominal aortic aneurysmectomy in patients with chronic obstructive pulmonary disease

OBJECTIVE

This study sought to identify risk factors associated with an unfavorable outcome after elective abdominal aortic aneurysm (AAA) repair in patients with chronic obstructive pulmonary disease (COPD).

METHODS

The clinical records of 158 patients who underwent elective open AAA repair with COPD determined from preadmission International Classification of Diseases-ninth revision codes during a 12-year period at the University of Michigan were reviewed. Patients with uncomplicated outcomes (group I) were compared with those with unfavorable postoperative outcomes (group II). The unfavorable outcomes were defined as myocardial infarction, acute renal failure, worsening respiratory insufficiency necessitating tracheostomy, or death within 30 days of surgery. Logistic regression analyses of variables that were identified as being statistically significant in the univariate analysis were used to develop a predictive model of these events.

RESULTS

Group I included 133 patients (77 men, 56 women) with a mean age of 70.1 years, and group II included 25 patients (13 men, 12 women) with a mean age of 71.4 years. Preoperative factors statistically related (P =.002) to an unfavorable outcome in group II patients included: suboptimal COPD management (fewer prescribed inhalers), lower hematocrit, preoperative renal insufficiency, and coronary artery disease. Importantly, abnormal preoperative spirometry and arterial blood gases were not predictive of a poor outcome. Univariate analysis also revealed increased hospital (25 versus 13 days; P =.0001) and intensive care unit (14 versus 4 days; P =.001) length of stays and a greater need for prolonged ventilation (8 versus 1 day; P =.039) for group II patients compared with group I patients. The 30-day mortality rate in the entire experience was 3.2% (5/158). No specific variables associated with mortality were identified.

CONCLUSION

Fewer prescribed inhalers, lower hematocrit, renal insufficiency, and coronary artery disease are preoperative factors associated with unfavorable outcomes after open elective surgical repair of AAA in patients with COPD. Intensive management of these factors may reduce the hazards of AAA operations in these patients. COPD alone should not be considered a deterrent to the surgical treatment of AAAs.

Non-cardiogenic pulmonary oedema in vascular surgery

Non-cardiogenic pulmonary oedema, an early manifestation of the adult respiratory disease syndrome, is a serious complication following major vascular surgery. Hypovolaemia, ischaemia-reperfusion injury, massive blood transfusion, transient sepsis and transient endotoxaemia are insults responsible for initiating the process in vascular surgical patients. Free radicals, cytokines and humoral factors released secondary to the above insults activate neutrophils and facilitate their interaction with the endothelium. Activated neutrophils marginate through the endothelium where they are responsible for tissue injury by the release of free-radicals and proteases. The lungs are a large reservoir of neutrophils and bear a significant part of the injury. Conventional therapy includes treating the underlying condition and providing respiratory support. A better understanding of the pathophysiology of this process has led to new experimental treatment options. Novel therapeutic interventions have included the use of compounds to scavenge free radicals, anti-cytokine antibodies, extracorporeal lung support, nitric oxide and artificial surfactant therapy. The multifactorial nature of this process makes it unlikely that a single "magic bullet" will solve this problem. It is more likely that a combination of preventative, prophylactic and therapeutic modalities may reduce the mortality of this condition.

Abdominal aortic aneurysm treatment: preliminary results with the Talent stent-graft system

PURPOSE

To evaluate the treatment of abdominal aortic aneurysm (AAA) with use of the endoluminal Talent stent-graft (TSG).

PATIENTS AND METHODS

In 10 men, AAA treatment was attempted with use of the TSG. All patients presented significant surgical risk, with chronic obstructive pulmonary disease and coronary arteriopathy. The mean age was 65.5 years (range, 57-82 years). The mean proximal neck diameter was 25.8 mm (range, 21.6-34 mm). Five of the TSGs were straight tubes and five were bifurcated systems. The main body of the TSG is made of a polyester graft material mounted on a self-expandable nitinol frame. The bifurcated system uses polytetrafluoroethylene (PTFE) material for the legs and extensions mounted on a self-expandable nitinol frame. The bifurcated grafts used a 22 to 27-F introducer and the extensions, a 18-F introducer through a surgical cutdown technique.

RESULTS

The TSG system was successfully implanted in nine patients and failed in one because of dislodgment after deployment, which required conversion to surgery. Four leaks occurred initially. One was sealed off with balloon dilation at the end of the procedure, one leak was treated with an additional extension, another leak disappeared spontaneously in 30 days, and the other leak required embolization 4 weeks after discharge. Seven patients were discharged on the third day after the procedure, and two patients were discharged at 1 and 2 weeks, respectively. Blood transfusion was necessary in three patients because of hematoma at the incision site in two patients, which required surgical revision for hemostasis, and because of transoperative bleeding in one patient. Follow-up time ranged from 2 to 15 months. The only death occurred 5 days postoperatively as a consequence of ischemic colitis and multisystem organ failure in the only patient who required surgery.

CONCLUSION

Treatment of AAA with the TSG system is effective for aneurysm exclusion. This device seems to provide a good alternative to surgery in patients who are otherwise considered to be at high risk for complications after direct surgical repair, but it is not without risk of complications.

[Prediction of respiratory complications after surgery of the abdominal aorta]

The most frequent type of complication in patients undergoing aortic surgery is respiratory. Preoperative lung function (PFT) and arterial blood gas measurement (ABG) are often carried out to assess the risk more precisely. The aim of the present retrospective study was to determine which value of lung function test could identify patients who developed such complications. "Receiver Operating Characteristic" (ROC) curves and the area beneath the curve for the diagnosis of respiratory complications were calculated for each variable of PFT and ABG. The greatest Youden index for each variable was chosen as indicative pulmonary function criterion of increased risk of pulmonary complications. One hundred and ninety-five patients (age: 65 +/- 10 years) were included. Respiratory complications occurred in 15% of patients. Respiratory complications increased from 12% if the vital capacity (VC) was > or = 77% of the predicted value to 35% if the VC was < 77% (P = 0.002), and from 10% if the FEV1 was > 76% to 34% if the FEV1 was > or = 76% (P = 0.0005). A decreased PaO2 or increased PaCO2 was not correlated with an increased incidence of respiratory complications. Length of stay in ICU or in hospital were increased when VC or FEV1 were low. Frequency of pulmonary complications was 9% in patients without PFT abnormalities, 16% in patients with either diminished VC or FEV1 and 35% in patients with both lowered VC and FEV1. However, all the areas under the ROC curves were < 0.7 and the sensitivity of the different variables was low. It is concluded that routine preoperative PFT and ABG cannot predict respiratory complications after abdominal aortic surgery.

Selection and preparation of high-risk patients for repair of abdominal aortic aneurysms

OBJECTIVE

To discuss the most important risk factors in patients who undergo surgical repair of an abdominal aortic aneurysm (AAA).

DESIGN

This update in vascular surgical repair highlights the criteria that identify high-risk patients, the useful preoperative tests, and the perioperative measures that can aid surgical recovery.

MATERIAL AND METHODS

In elective repair of AAAs, high-risk patients are those with severe coronary or valvular heart disease, decompensated chronic obstructive pulmonary disease, severe cerebrovascular disease, chronic renal failure, hepatic cirrhosis with portal hypertension, and chronic hematologic disorders associated with bleeding dysfunction. Patients with unstable or severely symptomatic heart disease should undergo preoperative coronary angiography and ventriculography. Pharmacologic stress testing is recommended for patients with clinical markers of serious coronary artery disease and other medical or physical factors that prevent any type of standard exercise stress testing.

RESULTS

Our experience with high-risk patients supports conventional repair of AAAs. Our preference for the midline abdominal incision in high-risk patients is substantiated by an operative mortality rate of 5.7% in comparison with a reported 7% mortality rate for nonresective therapy. Approximately one in three high-risk patients will have a serious postoperative complication, the most common of which is a cardiac event. Most patients recover after a slightly prolonged hospital stay.

CONCLUSION

Despite an increased operative risk, patients with a stable medical condition and an AAA larger than 6 cm in diameter should be considered for elective repair. High-risk patients with smaller aneurysms (5 to 6 cm in diameter) should undergo efforts to stabilize or to improve their general medical condition before elective operation.