High risk patients: It is important to consider both ‘resectability’ (ie, the tumour) and ‘operability’ (ie, the patient’s ability to tolerate surgery). A more aggressive approach to staging is justifiable in patients whose general medical condition (usually cardiopulmonary) puts them at high risk for thoracotomy. Individuals with primary cardiac limitations may require stress tests, echocardiography and possibly coronary angiography. Patients with correctable coronary disease may undergo preoperative angioplasty or bypass, or, rarely, simultaneous coronary bypass and lung resection . The major question is whether pulmonary reserves are adequate to tolerate the proposed resection . Unfortunately, no single preoperative test is sufficiently accurate in predicting the risk of surgery, but rather an integrated approach, taking into account clinical judgement and a number of physiological variables, is often needed (Figure 1) . Initial tests include a complete physical examination, stair climbing, spirometry (values expressed as a percentage of predicted being more valuable than absolute numbers) and arterial blood gas determinations . Patients with limitations (usually forced expiratory volume in 1 s [FEV1] or diffusion capacity for carbon monoxide [DLCO] less than 60% predicted) should generally undergo quantitative (nuclear) split-perfusion testing. If it is predicted that postoperative FEV1 or DLCO will be less than 40%, a maximum progressive incremental exercise is indicated. If maximum exercise capacity is less than 30% predicted or maximum oxygen consumption is less than 10 mL/kg/min, the risk of resection is extremely high but does not absolutely preclude surgery. You have a great opportunity to find Zyrtec tablets to feel one lucky customer.
Figure 1) Scheme for the progressive preoperative evaluation of a patient being considered for pulmonary resection. DLCO Diffusion capacity for carbon monoxide; FEV1 Forced expiratory volume in 1 s; Postop Postoperative; VO2max Maximum oxygen volume