The study was performed on 11 female and 9 male dogs to investigate the effect of hypertonic NaCl in severe hypotension and shock caused by acute pulmonary artery obstruction. The investigation was performed in Dicle University Healt Research Center (DUHRC). The youngest subject was six months old and the oldest was two years old. Their mean body weight was found as 19 kg. All the subjects were operated under general anesthesia. Invasive measurements of arterial pressure were performed through the right femoral artery by monitorization. All subjects were performed left thoracotomy, entrance to thorax was through 5th intercostal space, and first left then right pulmonary artery were circumferenced loosely with tape. After this, mean pulmonary artery pressures are recorded with the help of monitor by inserting canulla into the pulmonary artery. Pulmonary artery pressures at 3rd, 5th, 10th, 13th, 15th, 18th and 21st minutes after ligation of right main pulmonary artery and left lower lobe pulmonary artery, and mean artery pressures are recorded. Sodium nitroprusside is given to half of the subjects and nitroglycerine is given to the other half in order to lower pulmonary hypertension. Pulmonary arterial pressure measurements following administration of these drugs are recorded. 7.5% of NaCl infusion to subjects is performed in case of hypotension and shock. Isotonic NaCl solution is used in the control group. Mean arterial pressures in group receiving sodium nitroprusside + 7.5% NaCl solution are found significantly higher statistically when compared to group receiving sodium nitroprusside + 0.9% NaCl isotonic solution. Difference in mean arterial pressures were not found statistically significant in the group receiving nitroglycerin + 7.5% NaCl when compared to group receiving nitroglycerin + 0.9% NaCl solution.