A modular dilation device is provided for inserting multiple dilators into a target patient tissue site. The modular dilation device includes a first dilator and a second dilator. The first dilator has a first dilator distal end and a first dilator inner lumen. The first dilator has a first dilator side wall opening. The first dilator distal end has a first dilator open tip. The first dilator has a first dilator open slit. The first dilator open slit extends between the first dilator side wall opening and the first dilator open tip. The second dilator has a second dilator distal end and a second dilator inner lumen. The second dilator distal end has a second dilator open tip. When the second dilator is joined to the first dilator, the second dilator open tip is adjacent to the first dilator side wall opening.