To determine which options are contraindications for thrombolysis in acute ischemic stroke, let's analyze each given option:

1. Recent head injury: Thrombolysis involves breaking down blood clots, which can increase the risk of bleeding. Therefore, a recent head injury is a contraindication due to the heightened risk of intracranial hemorrhage.
2. Recent MI (Myocardial Infarction): After a myocardial infarction, patients are at risk of hemorrhagic complications and may be on medications like antiplatelets or anticoagulants, which further increases the risk of bleeding if thrombolytics are administered. Hence, it's considered a contraindication.
3. Hypertension > 150/100 mm Hg: While hypertension is a concern, the threshold usually considered a contraindication for thrombolysis is >180/110 mm Hg. Hence, isolated hypertension >150/100 mm Hg may not necessarily contraindicate thrombolysis, although BP control is necessary.
4. GI bleeding in the last 3 weeks: Any recent significant bleeding is a contraindication to thrombolysis, as it poses a risk of exacerbating bleeding due to the treatment.

Based on the analysis:

• Statements 1, 2, and 4 are indeed contraindications.
• Statement 3 (hypertension > 150/100 mm Hg) is not typically an absolute contraindication in acute ischemic stroke management with thrombolysis; rather, it's more important to manage blood pressure carefully at the recommended thresholds.

Therefore, the correct answer is: 1, 2 and 4.