Anesthesia Coding Alert

Dorsal (or spinal) column stimulation (DCS) is a treatment for patients with chronic, intractable pain that has not responded to other treatments. DCS interrupts the flow of nerve signals to the brain, replacing pain with a tingling sensation. When deemed medically necessary, DCS is reimbursable by Medicare and most private insurers. However, local Medical review policies (LMRPs) and many private carriers provide detailed limits on coverage. Further, one anesthesiologist (as a pain management specialist) may perform the surgery while another anesthesiologist administers anesthetic for this staged procedure. For anesthesia coders and billers, pain relief comes in knowing how to code correctly for the anesthesiologists' services for each stage of the procedure, and coders must know what documentation is needed to meet the carriers' criteria for coverage.
 
In the first stage of the procedure, electrodes are inserted into the epidural space next to the spinal column, and an external device generates electrical impulses to the electrodes. The patient is monitored to determine the efficacy of treatment. If the trial succeeds, a spinal neurostimulator pulse generator is inserted subcutaneously and connected to the implanted electrodes. Follow-up care includes electronic analysis of the implanted neurostimulator pulse generator system and may include subsequent intraoperative reprogramming or replacement of the pulse generator.

Patients Must Meet Treatment Criteria

 
Devona Slater, CMPC, president of Auditing for Compliance and Education Inc., a consulting firm in Leawood, Kan., that focuses on physician compliance plans and anesthesiology and pain management, says patients should be carefully selected for DCS treatment because of the strict limits of coverage for the procedures. She suggests that patients meet the following criteria:
 

exhibit a demonstrated pathology
 

fail to respond to more conservative therapies
 

not be candidates for further surgical intervention
 

are free of serious drug problems/habits
 

have undergone a psychiatric evaluation
 

have predominately radiating extremity pain.
 
Most LMRPs also require that the facilities, equipment and professional support personnel required for the proper diagnosis, treatment training, and follow up of the patient be available, and that demonstration of pain relief with a temporary implanted electrode precedes permanent implantation.
 
According to the LMRP for Empire Medical, New York's Part B Medicare carrier, ICD-9 code lists may cover a range and include shortened codes. It is the coder's responsibility to avoid shortened codes by selecting a code(s) carried out to the highest level of specificity. It is not enough to link the procedure to a correct and payable diagnosis."
 
Slater says that patients likely to meet these criteria may present diagnoses such as arachnoiditis (322.2), neuralgia/neuritis (723.4, 724.3-4, 729.2), postlaminectomy syndrome (722.81-83) or reflex sympathetic dystrophy  (337.21-337.29). She adds that LMRPs and private carriers can provide coders with a complete list of covered diagnosis codes. She also recommends preauthorizing the course of treatment, especially as some workers' compensation and other commercial carriers require it.

Temporary Insertion

 
"While there are different methods for placing electrodes, percutaneous placement is the most common," Slater says. The surgeon or an anesthesiologist performs the placement. Lead implantation is done under local anesthesia or monitored anesthesia care (MAC). The physician who places stimulator leads should use 63650 (percutaneous implantation of neurostimulator electrode array, epidural).
 
Anesthesia for the placement of the electrodes is usually delivered by a separate provider. Vicki Embich, anesthesia coding secretary of the West Florida Medical Center Clinic in Pensacola, Fla., says, "Coding for the anesthesiology services would include 63650 and 00300 (anesthesia for procedures on the integumentary system, muscles and nerves of the head, neck, and posterior trunk, not otherwise specified), with a base value of five units plus time." 
 
Note: While the ASA Crosswalk lists a corresponding anesthesia code of 00640 (anesthesia for closed procedure on cervical, thoracic or lumbar spine) for 63650, this code is not yet recognized in CPT 2001.
 
Embich also suggests that if MAC is the mode of administration, modifiers may be required for Medicare claims. Append modifier -QS (monitored anesthesia care service) to the anesthesia code in addition to the standard HCPCS modifier describing the anesthesiologist's level of participation or if a certified registered nurse anesthetist (CRNA) is involved. These modifiers include -AA (anesthesia services performed personally by anesthesiologist); -QY (medical direction of one certified registered nurse anesthetist by an anesthesiologist); -QK (medical direction of two, three, or four concurrent anesthesia procedures involving qualified individuals); and -QX (CRNA service: without medical direction by a physician).
 
A neurostimulator may also be inserted via laminectomy, and the appropriate surgical code is 63655 (laminectomy for implantation of neurostimulator electrodes, plate/paddle, epidural). The anesthesia provider would code using 63655 and 00630 (anesthesia for procedures in lumbar region; not otherwise specified) with eight base units plus time. Alternative anesthesia codes include 00600 (anesthesia for procedures on cervical spine and cord; not otherwise specified) and 00620 (anesthesia for procedures on thoracic spine and cord; not otherwise specified), depending on the region where the neurostimulators are implanted. Both 00600 and 00620 carry a base value of 10 plus time.
 
Note: Temporary placement procedures are covered in an in- or outpatient hospital or ambulatory surgical center. However, if procedure 63655 is performed in an ambulatory surgical center, many local Medicare carriers will not reimburse for facility or equipment fees, i.e., E0753 (implantable neurostimulator electrodes, per group of four).
 
Following the temporary insertion of the electrodes and the attachment of the lead wires to an external generator, the patient undergoes a trial period to determine if the spinal stimulation reduces pain. The trial period can last from 24 hours to four months. "If there is no relief, the surgeon and anesthesia provider are still eligible for reimbursement," Slater says. "However, if the patient has at least a 50 percent reduction in pain, he or she can be scheduled for permanent insertion of a pulse generator." She adds that evaluation of pain during the 90-day post-surgical period is considered part of the surgeon's global fee and cannot be billed separately.

Permanent Insertion

 
Slater states that the implantation of a pulse generator is done under MAC or general anesthesia. "The code for surgery is 63685 (incision and subcutaneous placement of spinal neurostimulator pulse generator or receiver, direct or inductive coupling). Anesthesiology services are coded with 00300 (anesthesia for all procedures on the integumentary system, muscles and nerves of head, neck, and posterior trunk, not otherwise specified), base value of five plus time."
 
Some Medicare carriers cover equipment for the permanent placement, including these new codes effective for dates of service on or after Jan. 1, 2001: E0756 (implantable neurostimulator pulse generator), E0757 (implantable neurostimulator radiofrequency receiver), and E0758 (radiofrequency transmitter [external] for use with implantable neurostimulator radiofrequency receiver). Embich advises that coders should check LMRPs to determine if equipment is covered in their state.

Testing for Continued Efficacy

 
Once the neurostimulator is implanted, the pain management physician performs follow-up evaluations to determine if and at what level the patient's pain is relieved. Intrinsic to this evaluation is an electronic analysis and possible reprogramming of the implanted pulse generator system. CPT 2001 lists four codes for these evaluations:
 

95970 -- electronic analysis of implanted neurostimulator pulse generator system (e.g., rate, pulse amplitude and duration, configuration of wave form, battery status, electrode selectibility, output modulation, cycling, impedance and patient compliance measurements); simple or complex brain, spinal cord, or peripheral (i.e., cranial nerve, peripheral nerve, automatic nerve, neuromuscular) neurostimulator pulse generator/transmitter, without reprogramming
 

95971 -- ... simple brain, spinal cord, or peripheral (except cranial nerve) neurostimulator pulse generator/transmitter, with intraoperative or subsequent programming
 

95972 -- ...complex brain, spinal cord ..., with intraoperative or subsequent programming, first hour
 

+95973 -- ... each additional 30 minutes after first hour.
 
Note: Use 95971, 95972 and +95973 if the patient requires reprogramming of the implanted stimulator. Code 95970 cannot be billed in conjunction with these other codes.

Replacement or Removal of the DCS System

 
Implanted pulse generators have a finite life span. For replacement of the pulse generator, 63685 and its associated anesthesia code 00300 would be used for this surgery. The patient or physician may decide the treatment is no longer effective. For excision of the electrodes, use 63660 (revision or removal of spinal neurostimulator electrode percutaneous array[s] or plate/paddle[s]). Use 63688 (revision or removal of implanted spinal neurostimulator pulse generator or receiver) for removal of the pulse generator. The corresponding anesthesia code is 00300 for both procedures.
 
Slater says that "the most important thing is documenting in the chart that all other types of intervention have failed. Carriers look at DCS as a treatment of last resort. Stay on top of these claims, and follow up with carriers no later than 45 days to ensure that the claim and documentation support their processing guidelines."