The patient’s hypotension, tachycardia, and unresponsiveness following a blow to the abdomen indicate the client is likely experiencing hypovolemic shock due to internal bleeding. The nurse must establish vascular access and begin fluid resuscitation to prevent circulatory collapse. The patient may eventually need to be intubated but is currently breathing and maintaining adequate oxygen saturations. The client is likely bleeding internally, so anticoagulant therapy is contraindicated at this time. Although the patient may eventually need an MRI, this is not the appropriate first action by the nurse.