Apparatus and method for forming an opening in patient's tissue

Abstract

A surgical instrument system for use in a surgical procedure is disclosed. The surgical instrument system may include an instrument configured to puncture the tissue of a patient and detect when the instrument has entered a lumen of the patient's body. Liquid may be present in the lumen or the lumen may be devoid of liquid or tissue. The instrument is configured to determine when the needle tip is engaged with a portion of patient's tissue and determine when the needle tip has exited that portion of the patient's tissue by detecting changes in properties of the tissue, specifically, electrical resistance.

1 . A method for performing a surgical procedure, the method comprising:
 inserting a needle tip of a surgical instrument into a tissue of a patient,   advancing the needle tip through the tissue,   monitoring an indicator of the surgical instrument while advancing the needle tip through the tissue, and   maintaining a position of the surgical instrument in response to the indicator indicating the needle tip has entered a target lumen of the patient.   
     
     
         2 . The method of  claim 1 , wherein the surgical instrument is operable to automatically retract the needle tip when the needle tip has entered the target lumen of the patient. 
     
     
         3 . The method of  claim 1 , wherein the surgical instrument includes a control circuit operable to measure a change in electrical resistance to determine when the needle tip has entered the target lumen of the patient and to activate the indicator to indicate the needle tip has entered the target lumen of the patient. 
     
     
         4 . The method of  claim 1 , wherein the surgical instrument includes a control circuit operable to measure a change in one or more electrical properties to determine when the needle tip has entered the target lumen of the patient and to activate the indicator to indicate the needle tip has entered the target lumen of the patient. 
     
     
         5 . The method of  claim 4 , wherein the control circuit is operable to apply an electrical charge to a plate positioned at the needle tip. 
     
     
         6 . The method of  claim 1 , wherein the target lumen is devoid of liquid and of tissue. 
     
     
         7 . The method of  claim 1 , wherein a liquid is present in the target lumen. 
     
     
         8 . A method for performing a surgical procedure, the method comprising:
 energizing a sensor circuit of a surgical instrument including a needle tip configured for insertion into a tissue of a patient,   monitoring an electrical signal received from the sensor circuit,   energizing an indicator in a first state when an electrical resistance value indicated by the electrical signal is less than a predetermined value corresponding to the needle tip being positioned in the tissue of the patient,   energizing the indicator in a second state when the resistance value indicated by the electrical signal is greater than a predetermined threshold corresponding to the needle tip being positioned in a lumen of the patient, and   energizing a retraction mechanism of the surgical instrument to move the needle tip away from the lumen of the patient.   
     
     
         9 . The method of  claim 8 , further comprising activating a timer when the resistance value indicated by the electrical signal is less than the predetermined value, wherein energizing the indicator in the first state includes energizing the indicator in the first state after a predetermined amount of time has elapsed from the activation of the timer. 
     
     
         10 . The method of  claim 8 , further comprising activating a timer when the resistance value indicated by the electrical signal is greater than the predetermined threshold, wherein energizing the retraction mechanism of the surgical instrument includes energizing the retraction mechanism of the surgical instrument after a predetermined amount of time has elapsed from the activation of the timer. 
     
     
         11 . A method for performing a surgical procedure, the method comprising:
 energizing an indicator of a surgical instrument to provide a first indication to a user when a needle tip is engaged with a portion of tissue of a patient, and   energizing the indicator to provide a second indication different from the first indication in response to the needle tip exiting the portion of tissue.   
     
     
         12 . The method of  claim 11 , further comprising automatically retracting the needle tip in response to the needle tip exiting the portion of tissue. 
     
     
         13 . The method of  claim 11 , wherein energizing the indicator to provide the second indication different from the first indication in response to the needle tip exiting the portion of tissue comprises energizing the indicator when the needle tip has entered a target lumen of the patient. 
     
     
         14 . The method of  claim 11 , wherein energizing the indicator to provide the second indication different from the first indication in response to the needle tip exiting the portion of tissue includes energizing the indicator when the needle tip has entered another portion of the patient.