Figure 61-7 The hemodynamic effect of thigh tourniquet inflation (single bar) and deflation (double bar) in an 86-year-old man with hypertension undergoing total-knee replacement. Notice the changes in pulmonary and systemic artery pressures with inflation and deflation of the tourniquet. The persistent elevation in pulmonary artery pressure after reinflation of the tourniquet after deflation (after third bar) may represent transient myocardial dysfunction.