What is the value of preoperative pulmonary function testing?

Successful pulmonary arterial embolization followed by curative surgery for a lepidic predominant lung adenocarcinoma with severe hypoxemia

Background

Lepidic predominant adenocarcinoma is characterized by frequent refractory hypoxemia due to intrapulmonary shunting. Severe hypoxemia can induce perioperative complications in case of thoracic surgery.

Case presentation

We report a case of a 67 year-old woman with localized lepidic adenocarcinoma in the right lower lobe with severe hypoxemia. A selective arterial lung embolization allowed an instantaneous correction of the hypoxemia, and a curative lobectomy was safely performed 1 week after without any complication. The staging was pT3N0M0, and the patient received adjuvant chemotherapy.

Conclusions

This is the first case-report of successful endovascular embolization before curative surgery for a lepidic predominant lung adenocarcinoma.

Arterial blood gases predict long-term prognosis in stage I non-small cell lung cancer patients

Background

Preoperative hypercapnia and hypoxemia are reportedly risk factors for postoperative complications. This study aimed to establish the long-term survival risk associated with abnormal preoperative arterial blood gases (ABGs) in patients with non-small cell lung cancer (NSCLC).

Methods

This study involved 414 patients with stage I NSCLC who underwent lobectomy/bilobectomy with mediastinal lymph node dissection. The patients were divided into groups with normal (n = 269) and abnormal (n = 145) ABGs.

Results

The patients in the normal ABG group (median age 67 years) were significantly younger than those in the abnormal ABG group (median age 70 years). There were no significant differences between the groups in gender, performance status, pathological stage, histology, postoperative complications, or preoperative comorbidity, except for chronic obstructive pulmonary disease/pulmonary fibrosis. The 3-, 5- and 10-year survival rates in the normal and abnormal ABG groups were 87, 77 and 56, and 78 , 63 and 42 %, respectively (p = 0.006). According to multivariate analysis, age, gender, performance status, non-adenocarcinoma, differentiation of resected tumor, pathological stage, any prior tumor and abnormal ABGs (risk ratio, 1.61) were independent prognostic factors.

Conclusions

Abnormal ABGs predict long-term survival risk in patients with NSCLC, which is important for planning therapeutic strategies.

Preoperative prediction of lung function in pneumonectomy by spirometry and lung perfusion scintigraphy

Introduction:

Nowadays an increasing number of lung resections are being done because of the rising prevalence of lung cancer that occurs mainly in patients with limited lung function, what is caused by common etiologic factor - smoking cigarettes. Loss of lung tissue in such patients can worsen much the postoperative pulmonary function. So it is necessary to asses the postoperative pulmonary function especially after maximal resection, i.e. pneumonectomy.

Objective:

To check over the accuracy of preoperative prognosis of postoperative lung function after pneumonectomy using spirometry and lung perfusion scinigraphy.

Material and methods:

The study was done on 17 patients operated at the Clinic for thoracic surgery, who were treated previously at the Clinic for Pulmonary Diseases “Podhrastovi” in the period from 01. 12. 2008. to 01. 06. 2011. Postoperative pulmonary function expressed as ppoFEV1 (predicted postoperative forced expiratory volume in one second) was prognosticated preoperatively using spirometry, i.e.. simple calculation according to the number of the pulmonary segments to be removed and perfusion lung scintigraphy.

Results:

There is no significant deviation of postoperative achieved values of FEV1 from predicted ones obtained by both methods, and there is no significant differences between predicted values (ppoFEV1) obtained by spirometry and perfusion scintigraphy.

Conclusion:

It is necessary to asses the postoperative pulmonary function before lung resection to avoid postoperative respiratory failure and other cardiopulmonary complications. It is absolutely necessary for pneumonectomy, i.e.. maximal pulmonary resection. It can be done with great possibility using spirometry or perfusion lung scintigraphy.

Respiratory Diseases

▪

Pulmonary arteriovenous fistulas have congenital and hereditary etiology, and patients are at risk for life-threatening rupture requiring surgery.

▪

Wegener's granulomatosis can affect any organ system, although renal and pulmonary involvement is most common; men ages 40 to 50 are at increased risk.

▪

Lymphomatoid granulomatosis affects cardiopulmonary, neurologic, and myeloproliferative systems; may result from opportunistic infection, and frequently progresses to lymphoma; men age 50 to 60 are at increased risk. Spontaneous remission occurs in some cases; mortality is 60% to 90% at 5 years.

▪

Churg-Strauss syndrome is usually associated with long-standing asthma, with men and women affected equally, and can affect any organ system; major cause of death is cardiac related.

▪

Primary pulmonary hypertension is a diagnosis of exclusion; women are affected twice as likely as men; right-to-left shunt may occur in 30%, secondary to patent foramen ovale; hypoxia with resultant heart failure is typical cause of death.

▪

Cystic fibrosis is an autosomal recessive disease, eventually fatal, with increased risk for airway obstruction, fluctuating pulmonary function, and chronic hypoxia; risk for spontaneous pneumothorax is 20%.

▪

Bronchiolitis obliterans organizing pneumonia is a pulmonary obstructive disease that may be reversible and usually resolves spontaneously.

▪

Idiopathic pulmonary hemosiderosis is associated with autoimmune disorders; patients have recurrent hemorrhage, pulmonary fibrosis, restrictive lung disease, and pulmonary hypertension, with some cases of spontaneous remission.

▪

Chronic eosinophilic pneumonia may be preceded by adult-onset asthma; women are at increased risk; prognosis is good.

▪

Goodpasture's syndrome is a genetic autoimmune disorder involving the pulmonary and renal systems.

▪

Pulmonary alveolar proteinosis, a lipoprotein-rich accumulation in alveoli, has three forms: congenital, decreased alveolar macrophage activity, and idiopathic; some cases of spontaneous remission occur.

▪

Sarcoidosis may affect any organ system; African American, northern European, and females are at greater risk; many patients are asymptomatic.

▪

Systemic lupus erythematosus may affect any organ system; women of childbearing age are at increased risk.

▪

Idiopathic pulmonary fibrosis is a rare interstitial lung disease, with smokers at increased risk for pulmonary malignancy; survival is usually 2 to 3 years from diagnosis; no effective treatment exists, with lung transplant the only therapeutic option.

▪

Acute respiratory distress syndrome (ARDS) is associated with underlying critical illness or injury, developing acutely in 1 to 2 days; mortality is 25% to 35%.

▪

Pulmonary histiocytosis X is an interstitial lung disease associated with cigarette smoking and an unpredictable course; some spontaneous remission occurs.

▪

Lymphangioleiomyomatosis involves progressive deterioration of lung function, associated with tuberous sclerosis and exacerbated by pregnancy, with women at increased risk; possible spontaneous pneumothorax and chylothorax; death usually results from respiratory failure.

▪

Ankylosing spondylitis is a genetic inflammatory process resulting in fusion of axial skeleton and spinal deformities, with men at increased risk; radiologic bamboo spine, sacral to cervical progression, and restrictive lung disease with high reliance on diaphragm; extraskeletal manifestations may occur.

▪

Kyphosis (exaggerated anterior flexion) and scoliosis (lateral rotational deformity) are spinal/rib cage deformities with idiopathic, congenital, or neuromuscular etiology; corrective surgery done if Cobb thoracic angle >50% lumbar angle >40%.

▪

Bleomycin is an antineoplastic antibiotic used in combination chemotherapy, with no myelosuppressive effect; toxicity can cause life-threatening pulmonary fibrosis.

▪

Influenza A is highly infectious, presenting with flulike symptoms and possible progression to ARDS; human-to-human exposure is through droplets or contaminated surfaces, with high risk for infants, children, pregnancy, chronically ill, or renal replacement therapy patients. No prophylactic treatment exists; treat patients with high index of suspicion without definitive testing; rRT-PCR and viral cultures are sensitive for pandemic H1N1 strain.

▪

Severe acute respiratory syndrome (SARS) is highly infectious, transmitted by coronavirus with human-to-human exposure via droplets or surfaces, and may progress to ARDS.

▪

Echinococcal disease of lung is from canine tapeworm, transmitted by eggs from feces; rupture of cyst may result in anaphylactic reaction or spread of disease to other organs; children are at increased risk. No transthoracic needle aspiration is done; surgery is only option.

Physiologic evaluation of the patient with lung cancer being considered for resectional surgery: ACCP evidenced-based clinical practice guidelines (2nd edition)

BACKGROUND

This section of the guidelines is intended to provide an evidence-based approach to the preoperative physiologic assessment of a patient being considered for surgical resection of lung cancer.

METHODS

Current guidelines and medical literature applicable to this issue were identified by computerized search and evaluated using standardized methods. Recommendations were framed using the approach described by the Health and Science Policy Committee.

RESULTS

The preoperative physiologic assessment should begin with a cardiovascular evaluation and spirometry to measure the FEV(1). If diffuse parenchymal lung disease is evident on radiographic studies or if there is dyspnea on exertion that is clinically out of proportion to the FEV(1), the diffusing capacity of the lung for carbon monoxide (Dlco) should also be measured. In patients with either an FEV(1) or Dlco < 80% predicted, the likely postoperative pulmonary reserve should be estimated by either the perfusion scan method for pneumonectomy or the anatomic method, based on counting the number of segments to be removed, for lobectomy. An estimated postoperative FEV(1) or Dlco < 40% predicted indicates an increased risk for perioperative complications, including death, from a standard lung cancer resection (lobectomy or greater removal of lung tissue). Cardiopulmonary exercise testing (CPET) to measure maximal oxygen consumption (Vo(2)max) should be performed to further define the perioperative risk of surgery; a Vo(2)max of < 15 mL/kg/min indicates an increased risk of perioperative complications. Alternative types of exercise testing, such as stair climbing, the shuttle walk, and the 6-min walk, should be considered if CPET is not available. Although often not performed in a standardized manner, patients who cannot climb one flight of stairs are expected to have a Vo(2)max of < 10 mL/kg/min. Data on the shuttle walk and 6-min walk are limited, but patients who cannot complete 25 shuttles on two occasions will likely have a Vo(2)max of < 10 mL/kg/min. Desaturation during an exercise test has not clearly been associated with an increased risk for perioperative complications. Lung volume reduction surgery (LVRS) improves survival in selected patients with severe emphysema. Accumulating experience suggests that patients with extremely poor lung function who are deemed inoperable by conventional criteria might tolerate combined LVRS and curative-intent resection of lung cancer with an acceptable mortality rate and good postoperative outcomes. Combining LVRS and lung cancer resection should be considered in patients with a cancer in an area of upper lobe emphysema, an FEV(1) of > 20% predicted, and a Dlco of > 20% predicted.

CONCLUSIONS

A careful preoperative physiologic assessment will be useful to identify those patients who are at increased risk with standard lung cancer resection and to enable an informed decision by the patient about the appropriate therapeutic approach to treating their lung cancer. This preoperative risk assessment must be placed in the context that surgery for early-stage lung cancer is the most effective currently available treatment for this disease.

Computed Tomography–Diagnosed Emphysema, Not Airway Obstruction, Is Associated with the Prognostic Outcome of Early-Stage Lung Cancer

PURPOSE

Because both emphysema and lung cancer can arise from biological damage caused by cigarette smoking, we investigated if the development of emphysema is associated with the clinical features of smoker's lung cancer.

EXPERIMENTAL DESIGN

The subjects were a consecutive series of 100 smokers who underwent lobectomy with hilar and mediastinal dissection for clinical stage I non-small cell lung cancer. We studied the relationship between the presence or absence of emphysema at the onset of the lung cancer and clinicopathologic features. Emphysema was diagnosed by measuring the low-attenuation area using computed tomography densitometry.

RESULTS

There were no differences in clinicopathologic variables, including the degree of smoking exposure between the patients with (n=58) and those without (n=42) emphysema, although male gender and airflow limitation were predominant in the patients with emphysema. The presence of emphysema, but neither male gender nor airflow limitation, adversely affected both overall and disease-specific survival. According to Cox regression analysis, emphysema was an independent prognosticator among age, gender, degree of smoking exposure, tumor size, nodal status, histologic subtype, histologic grade, and microvessel invasion. These results were stabilized by a bootstrap sampling model.

CONCLUSIONS

Computed tomography-diagnosed emphysema, but not airway obstruction, is associated with poor prognosis in smokers with early-stage lung cancer. Thus, routine computed tomography densitometry in smokers with lung cancer should be mandatory.

Quantitative Computed Tomography Versus Spirometry in Predicting Air Leak Duration After Major Lung Resection for Cancer

BACKGROUND

Emphysema is a well-known risk factor for developing air leak or persistent air leak after pulmonary resection. Although quantitative computed tomography (CT) and spirometry are used to diagnose emphysema, it remains controversial whether these tests are predictive of the duration of postoperative air leak.

METHODS

Sixty-two consecutive patients who were scheduled to undergo major lung resection for cancer were enrolled in this prospective study to define the best predictor of postoperative air leak duration. Preoperative factors analyzed included spirometric variables and area of emphysema (proportion of the low-attenuation area) that was quantified in a three-dimensional CT lung model. Chest tubes were removed the day after disappearance of the air leak, regardless of pleural drainage. Univariate and multivariate proportional hazards analyses were used to determine the influence of preoperative factors on chest tube time (air leak duration).

RESULTS

By univariate analysis, site of resection (upper, lower), forced expiratory volume in 1 second, predicted postoperative forced expiratory volume in 1 second, and area of emphysema (< 1%, 1% to 10%, > 10%) were significant predictors of air leak duration. By multivariate analysis, site of resection and area of emphysema were the best independent determinants of air leak duration. The results were similar for patients with a smoking history (n = 40), but neither forced expiratory volume in 1 second nor predicted postoperative forced expiratory volume in 1 second were predictive of air leak duration.

CONCLUSIONS

Quantitative CT is superior to spirometry in predicting air leak duration after major lung resection for cancer. Quantitative CT may aid in the identification of patients, particularly among those with a smoking history, requiring additional preventive procedures against air leak.

Role of Quantitative CT in Predicting Hypoxemia and Complications After Lung Lobectomy for Cancer, With Special Reference to Area of Emphysema

STUDY OBJECTIVES

To determine the ability of quantitative CT, with special reference to area of emphysema, to predict early postoperative oxygenation capacity and outcome after lung lobectomy for cancer.

METHODS

Sixty-two consecutive patients scheduled to undergo lung lobectomy for cancer were enrolled in this study. The area of emphysema (< - 910 Hounsfield units) was measured on a three-dimensional CT lung model. Arterial oxygen saturation (Sao(2)) was calculated from Pao(2) measured 1 day before and 1 day after surgery with patients at rest breathing room air. A patient was considered to have recovered at the completion of a standardized management regimen.

RESULTS

Postoperative Sao(2) (postSao(2)) was predicted by the baseline value and the area of emphysema with the use of a regression equation. Ten of the 62 patients (16%) had postoperative cardiopulmonary complications (CPCs). The median time to postoperative recovery was 3 days (range, 1 to 17 days). Predicted postSao(2) and predicted postoperative FEV(1) were shown to be significant independent predictors of postoperative CPCs as well as postoperative recovery time.

CONCLUSION

Determining the area of emphysema by quantitative CT is useful in predicting early postoperative oxygenation capacity. Predicted oxygenation capacity and predicted ventilatory capacity independently affect perioperative outcomes. Therefore, using quantitative CT in combination with spirometry may improve risk prediction in patients undergoing lung lobectomy for cancer. However, the role of quantitative CT in grading nonemphysematous lung diseases, such as interstitial lung diseases, must be investigated.

Utilization of the pulmonary function test laboratory in the evaluation of respiratory disorders in the Al-Amiri Hospital: a secondary medical center

OBJECTIVE

The aim of this study was to describe the current use of pulmonary function tests (PFT) and the degree of matching between the diagnoses at referral and after the test.

SUBJECTS AND METHODS

A pre-test questionnaire was administered to 464 (5-88 years) patients referred to the PFT laboratory followed by a complete PFT test. The results of the patients' tests were analyzed in terms of the diagnosis before the test, its relation to symptoms, and the rate of concordance between the diagnoses before and after the test.

RESULTS

The most referrals were from the medical Outpatient Department; 61%) and the most frequent diagnosis before the test was asthma (31.8%). Of the 464 patients, 34% were currently smoking cigarettes, and the most common symptoms were chronic dyspnea (30.2%) and chronic cough (19.6%). The chronicity of symptoms showed some association with the diagnosis before PFT in the case of chronic obstructive pulmonary disease (COPD) showing the symptom of dyspnea (p = 0.05), and COPD and restrictive lung disease with cough (p < 0.05). The overall rate of concordance in matching diagnoses before and after the test was 60.4% by consultant physicians and 51.9% by non-consultants, with an overall rate of 55% by all physicians.

CONCLUSION

Our findings show that there should be better utilization of the PFT laboratory by physicians in all sub-specialities and there is a need to facilitate its use to make a better functional diagnosis.

Estudo prospectivo do derrame pleural pós-cirurgia abdominal e dos fatores de risco associados: avalição por ultra-sonografia

MOTIVAÇÃO: Derrame pleural é alteração pulmonar comumente observada em exames de imagem após cirurgias abdominais eletivas, sem repercussão clínica na maioria dos enfermos, devendo ser individualizada das complicações pulmonares que requerem tratamento. Sua incidência, bem como os indicadores de risco, são desconhecidos em nosso meio. OBJETIVO: Determinar, pela ultra-sonografia, a incidência de derrame pleural pós-operatório (DPPO) em cirurgias abdominais eletivas e averiguar suas possíveis associações com fatores de risco relacionados aos doentes e procedimentos anestésico-cirúrgicos. MATERIAIS E MÉTODOS: Estudaram-se 21 (56,8%) mulheres e 16 (43,2%) homens, entre 29 e 76 anos, submetidos a cirurgias abdominais eletivas. Os exames ecográficos foram realizados no pré-operatório e 48 horas após a cirurgia. Foram estudados os fatores de risco associados ao paciente - idade maior de 60 anos, sexo, obesidade, tabagismo, etilismo e presença de doenças associadas -, e ao procedimento anestésico-cirúrgico - cirurgia para ressecção de câncer, classe ASA > 2, tempo anestésico-cirúrgico, incisão longitudinal e incisão > 15 cm. A litíase biliar (43,2%) e a presença de câncer gastrintestinal (43,2%) foram os principais responsáveis pela indicação cirúrgica. O DPPO foi graduado de pequeno, médio e grande. RESULTADOS: A incidência de DPPO foi de 70,3% (26/37). Dois (5,4%) desses doentes evoluíram com complicações pulmonares graves, um deles vindo a falecer. Idade maior de 60 anos, tabagismo, etilismo, obesidade e presença de doenças associadas não influenciaram o aparecimento de DPPO. Cirurgia para ressecção de câncer, classe ASA > 2, incisão longitudinal e incisão > 15 cm associaram-se de modo significante à presença de DPPO, que ocorreu mesmo na vigência de antibioticoprofilaxia. O tempo de permanência hospitalar foi 2,4 vezes maior nos doentes com DPPO. CONCLUSÃO: A ocorrência de derrame pleural em pós-operatório de cirurgia abdominal eletiva é muito freqüente. A maioria dos DPPO é autolimitada, evoluindo de modo assintomático. A ecografia na constatação do DPPO mostrou-se efetiva e sua utilização merece ser difundida.

Noncardiac pulmonary, endocrine, and renal preoperative evaluation of the vascular surgical patient

Patients who have vascular disease who are to undergo an operation are at risk for developing perioperative and postoperative complications caused by coexisting diseases. A comprehensive preoperative evaluation is critical in identifying these coexisting diseases, and the anesthetic plan might require modification. This article focuses on important aspects of the pulmonary, endocrine (diabetes), and renal systems during the preoperative evaluation of the vascular surgical patient.

The physiologic evaluation of patients with lung cancer being considered for resectional surgery

The preoperative physiologic assessment of a patient being considered for surgical resection of lung cancer must consider the immediate perioperative risks from comorbid cardiopulmonary disease, the long-term risks of pulmonary disability, and the threat to survival due to inadequately treated lung cancer. As with any planned major operation, especially in a population predisposed to atherosclerotic cardiovascular disease by cigarette smoking, a cardiovascular evaluation is an important component in assessing perioperative risks. Measuring the FEV(1) and the diffusing capacity of the lung for carbon monoxide (DLCO) measurements should be viewed as complementary physiologic tests for assessing risk related to pulmonary function. If there is evidence of interstitial lung disease on radiographic studies or undue dyspnea on exertion, even though the FEV(1) may be adequate, a DLCO should be obtained. In patients with abnormalities in FEV(1) or DLCO identified preoperatively, it is essential to estimate the likely postresection pulmonary reserve. The amount of lung function lost in lung cancer resection can be estimated by using either a perfusion scan or the number of segments removed. A predicted postoperative FEV(1) or DLCO < 40% indicates an increased risk for perioperative complications, including death, from lung cancer resection. Exercise testing should be performed in these patients to further define the perioperative risks prior to surgery. Formal cardiopulmonary exercise testing is a sophisticated physiologic testing technique that includes recording the exercise ECG, heart rate response to exercise, minute ventilation, and oxygen uptake per minute, and allows calculation of maximal oxygen consumption (.VO(2)max). Risk for perioperative complications can generally be stratified by .VO(2)max. Patients with preoperative .VO(2)max > 20 mL/kg/min are not at increased risk of complications or death; .VO(2)max< 15 mL/kg/min indicates an increased risk of perioperative complications; and patients with .VO(2)max < 10 mL/kg/min have a very high risk for postoperative complications. Alternative types of exercise testing include stair climbing, the shuttle walk, and the 6-min walk. Although often not performed in a standardized manner, stair climbing can predict .VO(2)max. In general terms, patients who can climb five flights of stairs have O(2)max > 20 mL/kg/min. Conversely, patients who cannot climb one flight of stairs have .VO(2)max < 10 mL/kg/min. Data on the shuttle walk and 6-min walk are limited, but patients who cannot complete 25 shuttles on two occasions will have .VO(2)max < 10 mL/kg/min. Desaturation during an exercise test has been associated with an increased risk for perioperative complications. Lung volume reduction surgery (LVRS) for patients with severe emphysema is a controversial procedure. Some reports document substantial improvements in lung function, exercise capability, and quality of life in highly selected patients with emphysema following LVRS. Case series of patients referred for LVRS indicate that perhaps 3 to 6% of these patients may have coexisting lung cancer. Anecdotal experience from these case series suggest that patients with extremely poor lung function can tolerate combined LVRS and resection of the lung cancer with an acceptable mortality rate and good postoperative outcomes. Combining LVRS and lung cancer resection should probably be limited to those patients with heterogeneous emphysema, particularly emphysema limited to the lobe containing the tumor.

Predicting pulmonary complications after nonthoracic surgery: a systematic review of blinded studies

PURPOSE

To determine the performance of variables commonly used in the prediction of postoperative pulmonary complications in patients undergoing nonthoracic surgery.

METHODS

We conducted a systematic review of the literature in English, using MEDLINE (1966-2001), manual searches of identified articles, and contact with content experts. All studies reporting independent and blinded comparisons of preoperative or operative factors with postoperative pulmonary complications were included. Two reviewers independently abstracted inclusion and exclusion criteria, study designs, patient characteristics, predictors of interest, and the nature and occurrence of postoperative pulmonary complications.

RESULTS

Seven studies fulfilled the inclusion criteria. The definition of postoperative pulmonary complications differed among studies, and the incidence of postoperative pulmonary complications varied from 2% to 19%. Of the 28 preoperative or operative predictors that were evaluated in the 7 studies, 16 were associated significantly with postoperative pulmonary complications, although only 2 (duration of anesthesia and postoperative nasogastric tube placement) were significant in more than one study. The positive (2.2 to 5.1) and negative (0.2 to 0.8) likelihood ratios for these 16 variables suggest that they have only modest predictive value. Neither hypercarbia nor reduced spirometry values were independently associated with an increased risk of postoperative pulmonary complications.

CONCLUSION

Few studies have rigorously evaluated the performance of the preoperative or operative variables in the prediction of postoperative pulmonary complications. Prospective studies with independent and blinded comparisons of these variables with postoperative outcomes are needed.

Preoperative assessment of the thoracic surgery patient: pulmonary function testing

Tests of pulmonary function before thoracic surgery can help to assess the risk of perioperative morbidity and mortality, and are the basis for estimating remaining lung function after resection of lung tissue. Testing has evolved over the past 50 years from reliance on the maximum breathing capacity to a range of studies including spirometry, and measurement of lung volume, diffusing capacity, and arterial blood gases, and the interpretation of these in conjunction with radionuclide scanning. The surgeon must consider both the early postoperative decrement in function and the level to which the patient is expected to recover. Although it is difficult to establish absolute limiting values, and current surgical techniques are blurring the boundary further, the reported experience underlying current guidelines is reviewed.

Video-assisted thoracoscopic esophagomyotomy for achalasia after pulmonary lobectomy

A 52-year-old man developed achalasia and a lung abscess due to aspiration pneumonia. We conducted a right upper lobectomy by thoracotomy for the abscess and, 2 weeks later, video-assisted thoracoscopic myotomy and fundoplication (modified Belsey Mark IV procedure) though the left thorax for achalasia. Three months after surgery, the patient was free of dysphasia and chest pain and had regained his original weight. Esophageal myotomy and fundoplication using video-assisted thoracoscopy appear to be feasible in treating achalasia involving impaired pulmonary function.

Recognition and management of preoperative risk

Internists are frequently asked to do preoperative consultations and to manage perioperative complications. Realistic goals are to identify patient factors that increase the risk of surgery, to quantify this risk in order to make decisions about the appropriateness of and timing of the surgery, to provide recommendations on how to minimize the risk, to identify and manage coexisting medical conditions and their associated medication requirements, to monitor the patient for perioperative problems, and to make recommendations to deal with these problems when they occur. With few exceptions, nonselective imaging and laboratory screening tests have repeatedly been shown to be of little value when the history and physical do not suggest a problem. The risk associated with the planned surgery can be estimated, with the most common serious complications being cardiac events. Updated versions of Goldman's risk indices are particularly helpful for this. Clinical variables are optimally combined with selective stress testing to discern which patients will benefit from preoperative revascularization. This has been studied best in the setting of vascular surgery. A critical guiding principle is that the value of revascularization must be judged in terms of long term gains rather than just immediate perioperative benefit. Other interventions include the selective use of beta blockers, adequate analgesia for all, control of hypertension, and appropriate volume management, especially in the settings of preexisting CHF or valvular disease. It must also be recognized that perioperative ischemia and CHF often present atypically. An approach that combines aspects of both the ACC/AHA and the ACP guidelines seems optimal. A variety of noncardiac issues must also be addressed. Postoperative pulmonary complications are common, especially with preexisting pulmonary disease, thoracic and upper abdominal surgery, and obesity. PFTs and ABGs are indicated in selected patients. Stopping smoking, incentive spirometry, and selective use of bronchodilators and antibiotics are helpful. Patients with rheumatologic diseases have specific concerns based on systemic manifestations of disease including anemia, thrombocytopenia, pulmonary fibrosis, pericarditis, and hypercoagulability; medication effects particularly from steroids and nonsteroidal anti-inflammatory drugs; and specific joint problems including contractures and atlantoaxial joint instability. Diabetes increases the risk of infection and cardiac complications. Prevention of ketoacidosis and glucose control are necessary and can be achieved through a variety of approaches, depending on whether the patient suffers from Type 1 or Type 2 diabetes. The threshold for transfusion has increased in recent years, as has the use of erythropoietin and autologous blood donation. There is no longer an absolute hemoglobin that requires transfusion, although most require transfusion for hemoglobins less than 8 mg/dL, especially in the setting of cardiac disease and bloody surgery. The elderly require surgery at an increased rate and often do not do as well as younger patients. The primary issues are, however, not their age but their increased frequency of underlying disease and diminished reserve. The latter makes them prone to postoperative delirium, sensitivity to medications, and cardiac and pulmonary problems. Despite the many diseases that patients often have and the stresses of surgery itself, modern anesthetic and surgical techniques allow almost all patients to undergo necessary procedures at acceptable risk. The internist plays a critical role in minimizing this risk even further.

Improvement of pulmonary function after lobectomy for non-small cell lung cancer in emphysematous patients

OBJECTIVE

Pulmonary emphysema is frequently associated with lung cancer and, because of the impaired pulmonary function involved, it may contraindicate surgical treatment. However, improvement of pulmonary function has been observed after surgical resection in patients with advanced emphysema. The aim of this study was to evaluate whether pulmonary emphysema, as assessed by pulmonary function tests and radiological evaluation, can influence postoperative respiratory function after lobectomy for non-small cell lung cancer (NSCLC).

METHODS

Respiratory function was evaluated before and after lobectomy for NSCLC. Radiological evaluation of emphysema was performed on chest X-ray and CT scan. Patients that had undergone chemo- or radiotherapy or had segmental or lobar atelectasis were excluded from the study.

RESULTS

Thirty-five patients entered the study. A decrease in static lung volumes was observed after surgery. Total lung capacity (TLC) decreased from 6.58+/-0.92 to 5.46+/-0.77 l; functional residual capacity (FRC) from 3.70+/-0.88 to 2.96+/-0.73 1 and residual volume (RV) from 2.93+/-0.78 to 2.2+/-0.53 l. However, in a subgroup of 10 patients (Group 1), dynamic volumes after surgery were unchanged or slightly increased (forced vital capacity (FVC) from 3.23+/-0.65 to 3.3+/-0.68 l; forced expiratory volume in 1 s (FEV1) from 2.14+/-0.51 to 2.25+/-0.54 l), and airway resistances (sRaw) decreased from 15.58+/-5.18 to 11.42+/-5.25 cm H2O/s. Preoperative data showed that these patients had a greater obstruction, with FEV1 changing from 69+/-12.42 to 72.70+/-13.72% of predicted, as compared with a change from 87+/-12.7 to 72.08+/-13.10% in the other group of 25 patients (Group 2). Correlation analysis reached statistical significance between FEV1% variation (deltaFEV1%) and preoperative FEV1 and FVC% (r = -0.49, P = 0.002 and r = -0.5, P = 0.001, respectively) and between delta (FEV1)% and radiological scores for 3-level CT (r = 0.39, P = 0.04) and the sum of chest X-ray, single and 3-level CT scores (r = 0.49, P = 0.01).

CONCLUSIONS

Pulmonary function may remain unchanged or even increase after lobectomy in patients with a pronounced emphysematous component of airway obstruction. The identification of preoperative parameters that identify this group of patients could extend the indications for the treatment of lung cancer in patients with pulmonary emphysema.

Prediction of hypoxemia and mechanical ventilation after lung resection for cancer

BACKGROUND

Hypoxemia usually occurs after thoracotomy, and respiratory failure represents a major complication.

METHODS

To define predictive factors of postoperative hypoxemia and mechanical ventilation (MV), we prospectively studied 48 patients who had undergone lung resection. Preoperative data included, age, lung volume, force expiratory volume in one second (FEV1), predictive postoperative FEV1 (FEV1ppo), blood gases, diffusing capacity, and number of resected subsegments.

RESULTS

On postoperative day 1 or 2, hypoxemia was assessed by measurement of PaO2 and alveolar-arterial oxygen tension difference (A-aDO2) in 35 nonventilated patients breathing room air. The other patients (5 lobectomies, 9 pneumonectomies) required MV for pulmonary or nonpulmonary complications. Using simple and multiple regression analysis, the best predictors of postoperative hypoxemia were FEV1ppo (r = 0.74, p < 0.001) in lobectomy and tidal volume (r = 0.67, p < 0.01) in pneumonectomy. Using discriminant analysis, FEV1ppo in lobectomy and tidal volume in pneumonectomy were also considered as the best predictive factors of MV for pulmonary complications.

CONCLUSIONS

These results suggest that the degree of chronic obstructive pulmonary disease in lobectomy and impairment of preoperative breathing pattern in pneumonectomy are the main factors of respiratory failure after lung resection.

Pulmonary function after posterior retroperitoneoscopic surgery

Pulmonary function tests were performed in 12 patients who underwent posterior retroperitoneoscopic surgery, before and on the 3rd and 7th days after operation. Forced vital capacity (FVC), forced expiratory volume in 1 second (FEV1), FEV1/FCV, vital capacity (VC), total lung capacity (TLC), residual volume (RV) and functional residual capacity (FRC) were not significantly different between before and after surgery. It is assumed that posterior retroperitoneoscopic surgery could be performed without impairment of pulmonary function after surgery.

Medical clearance for gynecologic surgery

Physicians are charged to "foremost do no harm." Thus, before doing any surgical procedure, surgeons must convince themselves that the risk to the patient does not outweigh the benefit. The patient with multiple medical problems has additional risk factors for elective surgery. In the past, that patient would be sent to their general practitioner for "medical clearance." With gynecologists now assuming that role for the patient, it is increasingly important for us to understand what comprises medical clearance to better assess hazards. Studies concerning medical clearance for surgery obtained in a MEDLINE search through March 1997 were reviewed; the recent advances that apply to gynecologic surgery are covered in this article.

Determinants of longer duration of endotracheal intubation after adult cardiac operations

BACKGROUND

Poor pulmonary reserve is a risk factor that is used to exclude some patients from major operations. However, the value of routine spirometry in patients undergoing cardiac operations has not been widely evaluated.

METHODS

The outcomes of 586 consecutive adult patients undergoing cardiac operations were reviewed retrospectively to assess predictors of longer duration of endotracheal intubation.

RESULTS

By univariate analysis, congestive failure (p < 0.001), cardiomegaly (p = 0.002), recent myocardial infarction (p = 0.039), priority of operation (p = 0.005), previous cardiac operation (p < 0.001), and renal insufficiency (p = 0.002) increased the risk of longer endotracheal intubation. Spirometry (forced vital capacity, forced expiratory volume at 1 second, the ratio of forced expiratory volume at 1 second to forced vital capacity) did not correlate with longer endotracheal intubation. Perioperative complications, such as myocardial infarction (p < 0.001), coma, reexploration for bleeding, and reduced cardiac output (p < 0.001 each), correlated with longer duration of intubation. By multiple regression, priority of operation (p = 0.03), congestive failure (p = 0.02), and previous cardiac operation (p = 0.005) among preoperative risks and bleeding, reduced cardiac output, stroke, coma, and MB fraction of creatine kinase released postoperatively (p < 0.001 each) predicted longer duration of endotracheal intubation.

CONCLUSIONS

Postoperative cardiac function and the occurrence of complications are more significant than preoperative pulmonary function in determining the duration of endotracheal intubation after cardiac operation. Routine spirometry is probably unnecessary for most adult cardiac patients.

Value of preoperative spirometry to predict postoperative pulmonary complications

In order to determine the incidence of postoperative pulmonary complications (POPC) and the value of preoperative spirometry to predict pulmonary complications after upper abdominal surgery, 24 women and 36 men (total 60 patients) were studied prospectively (mean age 48 center dot 3 years). On the day before the operation and for 15 days after the operation, each patient's respiratory status was assessed by clinical examination, chest radiography, spirometry and blood gas analysis, and patients were monitored for pulmonary complications by a chest physician and a surgeon independently. In this study, postoperative pulmonary complications developed in 21 (35%) patients (pneumonia in 10 patients, bronchitis in nine patients, atelectasis in one patient, pulmonary embolism in one patient). Of 31 patients with abnormal preoperative spirometry, 14 (45 center dot 2%) patients showed complications, whereas among 29 patients with normal preoperative spirometry, 7 (24 center dot 1%) patients showed complications (P <0 center dot 05). The incidence of POPC was higher in patients with advanced age, smoking, preoperative abnormal findings obtained from physical examination of the chest, higher ASA class and longer duration of operation. The sensitivity (0 center dot 76) and specificity (0 center dot 79) of abnormal preoperative findings obtained from physical examination to predict POPC were higher than abnormal preoperative spirometry (0 center dot 67 and 0 center dot 56 retrospectively). There was no significant difference between patients with and without pulmonary complications in regard to weight, serum albumin, type of incision, incidence of abnormal preoperative blood gases and duration of postoperative hospital stay. We conclude that POPC is still a serious cause of postoperative morbidity. Multiple risk factors include preoperative abnormal spirometry responsible for development of POPC. If used alone, spirometry has limited clinical value as a screening test to predict POPC after upper abdominal surgery.

The lung cancer in the elderly: the surgical approach

The experience accumulated in a 5-year period with the surgical treatment of lung cancer in the elderly is reviewed. The cases of 171 patients treated between December 1989 and November 1994, were evaluated retrospectively, according to a selected groups of parameters. Fifty patients underwent thoracotomy, and the recorded postoperative complications were analyzed. The most important factors for predicting complications were the oxygen partial pressure in the arterial blood (PO(2)), the forced expiratory volume/1 sec (FEV(1)), the seriousness of the surgical intervention, and the duration of general anesthesia. The correct selection of patients and an adequate treatment of complications may be crucial for the success of surgical therapy of elderly patient.

Preoperative assessment of older adults

Caring for older patients who need surgery presents challenging medical situations. The clinical paradigm involves identifying coexisting disease, defining the urgency of the intervention, and predicting postoperative complications based on the type of surgery planned. The prime function of the medical consultant is searching for correctable medical conditions. The consultant must carefully identify coexisting and comorbid conditions. Emergency surgery should be avoided, if possible, by elective planning. The risk of surgery varies with the procedure. Non-body cavity surgery, with the exception of hip fracture repair, is usually tolerated well. Age is a risk factor for surgery, but coexisting disease is more important than age alone. The net effect of improvements in surgical outcome advances the age at which surgical risk becomes prohibitive.

Adherence to established guidelines for preoperative pulmonary function testing

Guidelines for ordering preoperative spirometry have been proposed by GM Tisi (1979) and more recently by the American College of Physicians (ACP). Requests for preoperative spirometries represent a significant portion of all requests for screening spirometry at our institution and utilize significant man-hours of technician time. We determined the percentage of these requests that did not meet the ACP guidelines and characterized why these requests were being generated. We sampled 441 screening spirometries performed by the Walter Reed Pulmonary Function Laboratory over a 4-week period. One hundred thirty-eight (31%) of these were done preoperatively and complete data were available in 135 cases. Patients in the analyzed group had a mean age of 59 years (+/- 14 years), ranging from 20 to 84 years of age. Fifty-two (39%) requests did not meet ACP guidelines. Most of these requests were associated with either normal spirometry (n = 34) or only mild spirometric abnormalities (n = 14). Spirometry revealed severe obstruction in only one case when the request was not indicated. No cases of moderate obstruction, severe restrictive pattern, or possible upper airway obstruction were found in the group of requests in which spirometry was not indicated. Of the requests that did not meet ACP guidelines, 21 met Tisi's broader guidelines. Most of these requests were found exclusively in patients older than 70 years of age (n = 13) and the morbidly obese (n = 4). Of the 31 studies that did not meet either set of guidelines, 25 occurred in asymptomatic, current, or prior smokers. In conclusion, during a 4-week study period at our institution, 39% of preoperative spirometry requests did not meet ACP guidelines. Most of the patients had been referred because of age greater than 70 years, morbid obesity, and a current/prior history of smoking. However, the literature does not support obtaining preoperative spirometry in such patients except for those undergoing only lung resection. We recommend stricter adherence to the ACP guidelines as a means of decreasing the number and cost of unnecessary spirometries being performed.