Cryoanalgesia and Therapeutic Cold

Number: 0297

Policy

1. Aetna considers the use of cryoanalgesia medically necessary for the temporary relief of pain due to chronic refractory trigeminal neuralgia (see Appendix for selection criteria).

2. Aetna considers intra-operative and post-operative cryoanalgesia of the intercostal nerves experimental and investigational for the management of post-thoracotomy pain and other types of chronic pain.

3. Aetna considers intra-operative and post-operative cryoanalgesia for reduction of post-tonsillectomy pain experimental and investigational because the effectiveness of these approaches has not been established.

4. Aetna considers passive cold compression therapy units (e.g., Aircast Cryo/Cuff products, the Polar Care Cub, and Polar Care Packs) medically necessary DME to control swelling, edema, hematoma, hemarthrosis and pain.  Aetna considers the passive cold compression therapy units experimental and investigational for all other indications because their effectiveness for indications other than the ones listed above has not been established.

5. Aetna considers active cold units with mechanical pumps and portable refrigerators with or without compression therapy (e.g., AutoChill, BioCryo Cold Compression System, Breg Polar Care Cube, Game Ready control units with attached cooling systems, Donjoy IceMan products, Ossur Cold Rush Cold Therapy System, Hilotherm devices, and VPULSE) experimental and investigational because they have not been proven to offer clinically significant benefits over passive cold compression therapy units. Note: Aetna considers active cold units with compression therapy are considered experimental and investigational, even if they are only prescribed for the compression component of the device. 

6. Aetna considers the use of devices that deliver both hot and cold therapy (e.g., Aqua Relief System, Waegener cTreatment, NanoTherm therapy system, ProThermo PT-9 therapy system, Thermacure Contrast Compression Therapy, Kinex ThermoComp device, VascuTherm 4, VascuTherm 5, Recovery+ Thermal Compression System, Thermo Plus-System) experimental and investigational for reducing pain and swelling after surgery or injury, or for other indications.  Studies in the published literature have been poorly designed and have failed to show that these devices offer any benefit over standard cryotherapy with ice bags/packs; and there are no studies evaluating their use as a heat source.

7. Aetna considers prophylactic hypothermia for the management of traumatic brain injury experimental and investigational because the effectiveness of this approach has not been established.

8. Aetna considers therapeutic hypothermia for the treatment of hemorrhagic stroke experimental and investigational because the effectiveness of this approach has not been established.

Note: Aetna considers passive hot and cold therapy medically necessary.  Mechanical circulating units with pumps have not been proven to be more effective than passive hot and cold therapy.

Background

Cryoanalgesia for Trigeminal Neuralgia

Trigeminal neuralgia (TN), also known as tic douloureux, is a disorder characterized by excruciating episodic pain in the areas innervated by one or more divisions (usually the mandibular and maxillary, rarely the ophthalmic divisions) of the trigeminal nerve.  The anti-epileptic drug carbamazepine (Tegretol) is the drug most frequently used for the management of TN.  For patients who can not tolerate carbamazepine because of its adverse side effects (poor liver function, confusion, ataxia, drowsiness, and allergic responses), the literature indicates baclofen and other anticonvulsant drugs such as clonazepam (Klonopin) may be useful.

Cryoanalgesia, cryotherapy, or cryoneurotomy has also been used in the treatment of TN.  It entails the use of high pressure (approximately 600 pounds per square inch) gas (nitrous oxide or carbon dioxide) administered by a 12- to 14-G needle-shaped cryoprobe.  Studies have shown that cryoanalgesia provides temporary pain relief or cure with minimal morbidity (e.g., no permanent sensory loss) in patients with refractory TN.

Intra-Operative and Post-Operative Cryoanalgesia for the Management of Post-Thoracotomy Pain

Thoracotomy, the establishment of an opening into the chest cavity for the management of various cardiopulmonary disorders/diseases, is one of the most painful surgical incisions.  Post-thoracotomy pain impairs patients' ability to breathe deeply and cough frequently to prevent atelectasis.  Pain relief medication may decrease the coughing reflex as well as depress respiratory functions when the dosage is high enough to achieve analgesia.  On the other hand, if the dosage of analgesics is too low to relieve pain, it may render patients with shallow breathing and inadequate coughing reflex.  Epidural anesthesia or analgesia may produce some pain relief, but the side effects of severe hypotension, nausea, and urinary retention, as well as the variability of effect limit the usefulness of this approach.  Intercostal or paravertebral nerve blocks by means of local anesthetics and severing of the intercostal nerves have also been used to reduce incisional pain following thoracotomy.  However, the duration of relief for neural blockade is only a few hours and the procedure is painful, while severing of the intercostal nerves during thoracotomy may result in neuromas, which cause late post-operative pain.

Cryoanalgesia has been used on the intercostal nerves to reduce post-thoracotomy pain.  Although the procedure is generally performed prior to closure of the chest at the completion of thoracotomy and may add 10 to 15 mins to the total operating time, it can also be carried out percutaneously in a clinical setting.  Cryoanalgesia of the intercostal nerves circumvents the need for repetitive injections of nerve blocks and avoids the toxicity of long acting agents, which may lead to chemically induced intercostal neuritis. 

Khanbhai et al (2014) examined if cryoanalgesia improves post-thoracotomy pain and recovery.  A total of 12 articles were identified that provided the best evidence to answer the question.  The authors, date, journal, study type, population, main outcome measures and results were tabulated.  Reported measures were pain scores, additional opiate requirements, incidence of hypoesthesia and change in lung function.  Half of the articles reviewed failed to demonstrate superiority of cryoanalgesia over other pain relief methods; however, additional opiate requirements were reduced in patients receiving cryoanalgesia.  Change in lung function post-operatively was equivocal.  Cryoanalgesia potentiated the incidence of post-operative neuropathic pain.  Further analysis of the source of cryoanalgesia, duration, temperature obtained and extent of blockade revealed numerous discrepancies; 3 studies utilized CO2 as the source of cryoanalgesia, and 4 used nitrous oxide but at differing temperatures and duration; 5 studies did not reveal the source of cryoanalgesia.  The number of intercostal nerves anesthetized in each study varied; 7 articles anesthetized 3 intercostal nerves, 3 articles used 5 intercostal nerves, 1 article used 4 intercostal nerves and 1 used 1 intercostal nerve at the thoracotomy site.  Thoracotomy closure and site of area of chest drain insertion may have a role in post-operative pain; but only 1 article explained method of closure, and 2 articles mentioned placement of chest drain through blocked dermatomes.  No causal inferences can be made by the above results as they are not directly comparable due to confounding variables between studies.  The authors concluded that currently, the evidence does not support the use of cryoanalgesia alone as an effective method for relieving post-thoracotomy pain.

1. appropriate dose regimes of gabapentinoids, anti-depressants, local anesthetics and regional anesthesia may potentially reduce the severity of both acute and chronic pain for patients;
2. ketamine was not effective at reducing chronic pain;
3. intercostal cryoanalgesia was not effective and has the potential to increase the risk of chronic pain; and
4. TIVA may be beneficial but the effects of opioids are unclear.

Cold Therapy Units and Hot/Ice Machine

Cold therapy devices combine cold temperatures and compression to decrease discomfort and swelling following injury or surgery to an extremity. The theory behind cold therapy is that by decreasing the temperature of the tissue, which produces vasoconstriction, pain is lessened, muscle spasm is decreased and inflammation is reduced.

Active cold therapy devices and combined heat and cold therapy devices utilize pneumatic or mechanical pumps that may be battery or electrically operated. The intended function of the pump is to provide cyclical compression and cooling or heating to the affected area. The devices generally consist of two basic parts: a wrap or wrap system and a control unit or pump, which is filled with ice and/or water. The control unit or pump circulates the cooled or heated water through the wrap system to the affected area.

Active cooling or heating devices

Examples of active cooling or heating devices include, but may not be limited to:

• Auto Chill Device –

  Cold therapy device in which a pump is used in conjunction with the Cryo/Cuff System. The pump automatically exchanges water from the pump to the cooler and eliminates the need for manual water recycling.

• cTreatment -

  Computer controlled heat and cold.

• Hilotherm -

  Heat and cold water pump with pads.

• Game Ready Accelerated Recovery System -

  System that combines cold and intermittent pneumatic compression therapies. It includes a computer that controls treatment time, level of compression and temperature. The unit continuously cycles liquid through circumferential wraps for consistent, long lasting cold treatment, even over large surface areas.

• Hot/Ice Thermal Blanket –

  Provides heat/cold therapy by the application of rubber pads (blankets) that are connected by a hose to a main cooling unit. The pads receive fluid that has circulated from the main unit and can be either hot or cold.

• IceMan Cryotherapy Unit –

  Utilizes a semi-closed loop system with a mechanical pump that allows warm water to circulate, at a constant flow rate, with cooler water providing consistent cold distribution throughout the pad.

• Kinex ThermoComp Device –

  Another example of a device that combines cold therapy with intermittent pneumatic compression.

• NanoTherm –

  System that combines cold or heat with intermittent pneumatic compression therapies. 

• Ossur Cold Rush Cold Therapy System –

   Combines cold pump with compression. 

• Thermocure Contrast Compression Therapy –

   Combines heat or cold pump with compression. 

• VitalWrap System –

  Consists of three components: a control unit, a tubing set and a thermal fabric wrap. The control unit, which includes a fluid reservoir, manages the temperature of water used by the system to supply heat or cold to the fabric wrap attached to the body. Compression is delivered through the wrap itself. 

• VPULSE -

  Intermittent pneumatic compression with cold water pump.

Passive cold therapy devices operate by gravity or a hand pump without the use of a battery or electricity. Generally, they consist of a cuff or wrap and a cooler. Ice water is placed in the reservoir or cooler. The cooler is placed above the affected body area or joint and then utilizes gravity to fill the cuff and compress the joint. 

Passive Cold Therapy Devices

Examples of passive cold therapy devices include, but may not be limited to:

• AirCast Cryo/Cuff System–

  Therapy system consisting of a cuff, a cooler and a hose. The hose exchanges cooled ice water between the cooler and the cuff which covers the injured area. Elevating the cooler fills and pressurizes the cuff. Compression is controlled by gravity and is proportional to the elevation of the cooler.

• Polar Care (PC) Cub Unit–

  Cold therapy system which includes a PC Cub cooler, manual pump and wrap on pads. The pads are held in place with elastic straps or an ace wrap. The built-in hand pump circulates the cold water through the polar pad, while at the same time increases the compression around the joint.

Cold therapy units are devices in which fluid flows through a blanket or cuff, providing immediate cooling to an affected area.  The AirCast Cryo/Cuff uses a insulated jug filled with cold water attached to a cuff.  Elevating the jug fills and pressurizes the cuff.  Compression is controlled by gravity, and is proportional to the elevation of the cooler.  When body heat warms the water, it is re-chilled simply by lowering the cooler.  Another passive cold compression therapy unit is the Polar Care Cub unit.

More complicated cold therapy units may employ mechanical pumps and refrigerators that are powered by battery or electricity (e.g., IceMan).  The Game Ready system is an example of an active cooling device that combines cold and intermittent pneumatic compression therapies.  The system consists of a wrap, a connector hose, and a control unit.  The wrap contains two internal chambers, one for air and the other for cooling water.  The microprocessor control unit features various adjustable compression cycles and temperature controls.  However, there is no evidence that these more complicated cold therapy units provide any additional benefit over the CryoCuff or conventional ice bags or packs.  Aetna's current policy on mechanical cold therapy pumps is consistent with Medicare DME MAC policy.

Leutz and Harris (1995) described a retrospective study that assessed 52 consecutive patients who underwent total knee arthroplasty (TKA).  A total of 33 patients underwent TKA and received cold therapy pads placed over a thin dressing in the operating room; 19 patients underwent TKA using an identical operative and post-operative procedure, but did not receive continuous cold therapy.  Continuous cold therapy consisted of 2 sterile plastic pads connnected by rubber hoses containing cool water from an electric main unit that maintained a constant temperature of 42 degrees F for the immediate post-operative period.  Cold therapy pads were used an average of 3 days and removed with the first dressing change.  Patients who had continuous cold therapy averaged a 200 ml decrease in post-operative blood loss.  There was no significant difference in the amount of narcotic use, transfusion requirements, or hospital stay between the two groups.  Post-operative swelling and range of motion were not consistently recorded.  Twenty-eight other variables were also examined, but no significant differences were found between groups.  Based on these results, the authors stated that they can not recommend continuous cold therapy or justify the extra expense for all patients who undergo TKA.

A Hot/Ice Machine consists of 2 rubber pads connected by a rubber hose to a unit that circulates hot or cold fluid through the pads.  Studies in the published literature have been poorly designed and have failed to show that the Hot/Ice Machine offers any benefit over standard cryotherapy with ice packs, and there are no studies evaluating the use of this device as a heat source.

The VitalWrap (VitalWear Inc. South San Francisco, CA) is an active heating/cooling device that allows the user to circulate either hot or cold fluid through the system.  The VitalWrap system consists of a bladder filled body wrap/pad, tubing, and a reservoir/pump device.  Cooled or heated water may be added to the pump reservoir and then circulated through the tubing to the body wrap/pad and then back to the reservoir.  The benefits of this type of device above other cooling or heating methods have not been established at this time.

Vascutherm (ThermoTek, Carrollton, TX) is an active cold compression therapy unit with a pneumatic pump.  It provides heating, cooling and compression therapies.  The device also includes a deep vein thrombosis (DVT) mode -- this is a compression (or air) only mode, that is intended to prevent DVT.  However, it provides no additional clinical utility or impact on health outcomes than the use of ice or compression wraps.

The TEC Thermoelectric Cooling System (Maldonado Medical, Phoenix, AZ) is marketed to reduce post-operative pain and edema.  It is an iceless cold therapy compression/DVT prophylaxis machine that can also provide heat.  It is limited to a cold temperature of 49 degrees F to minimize the potential for frostbite.  However, it provides no additional clinical utility or impact on health outcomes than the use of ice or compression wraps.

1. cold-compression,
2. contrast-compression, and
3. intermittent pneumatic compression for DVT prophylaxis.

Continuous cold is delivered by a solid-state system without ice.  Cold temperature is microprocessor-controlled within 1^° making this one of the safest devices for unsupervised use in a patient's home.  Contrast therapy cycles every 30 mins with cold at 49° for 20 mins followed by heat at 105^° for 10 mins.  Intermittent compression is delivered distal-to-proximal through a segmented pad.  Deep vein thrombosis prophylaxis is delivered from a rapid inflation pump at 50 mm Hg through a calf pad or 100 mm Hg through a foot pad.  All 3 therapies are delivered separately, however cold-compression and DVT compression can run at the same time with the device cycling DVT compression separate from limb compression.  The Kinex ThermoComp^™ Device is intended to treat post-operative injuries in the home, to reduce edema and pain, to improve blood flow to the surgical site, and to provide DVT prophylaxis therapy for high-risk patients. However, there is a lack of evidence regarding the safety and effectiveness of this device.

According to the manufacturer, the VascuTherm2 solid state device provides heat, cold (without ice), compression, and/or DVT prophylaxis therapy.  The system is pre-programmed per written physician's instructions for fully automatic, safe, trouble-free use in the patient's home.  It is indicated for pain, edema, and DVT prophylaxis for the post-operative orthopedic patient.  The precisely controlled temperature range of 43 degrees F to 105 degrees F insures against frost-bite or burns.  Therapy times are also pre-programmed to insure maximum patient compliance.  It is extremely easy for patients to set up and use. However, there is a lack of evidence regarding the safety and effectiveness of this device.

Intra-Operative and Post-Operative Cryoanalgesia for Reduction of Post-Tonsillectomy Pain

In a systematic review, Raggio and colleagues (2018) examined the effectiveness of intra-operative cryoanalgesia in the management of post-operative pain among patients undergoing palatine tonsillectomy.  These investigators performed a systematic review of PubMed, Medline, Embase, Google Scholar, and Cochrane trial registries through January 2017 using the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) standards.  They included English-language RCTs evaluating patients of all age groups with benign pathology who underwent tonsillectomy with cryoanalgesia versus without.  A total of 3limited quality RCTs involving 153 participants (age range of 1 to 60 years) were included.  Cryoanalgesia was performed with a cryotherapy probe (-56°C) in 1 trial and ice-water cooling (4°C to 10°C) in 2.  In the 3 trials reviewed, patients who received cryoanalgesia reported 21.38 %, 28.33 %, and 31.53 % less average relative post-operative pain than controls on the visual analog scale (VAS).  Review of secondary outcomes suggested no significant difference in time to resume normal diet (2 studies) or post-operative bleeding (2 studies) between the 2 groups.  Cryoanalgesia allowed patients to return-to-work 4 days earlier than controls in 1 study; 2 studies reported a trend toward less post-operative analgesia use among the treatment group; however, no statistical conclusions could be drawn.  The authors concluded that available evidence suggested that patients undergoing tonsillectomy with cryoanalgesia experienced less average post-operative pain without additional complications.  These preliminary findings need to be validated by well-designed studies.

Furthermore, UpToDate reviews on “Tonsillectomy (with or without adenoidectomy) in children: Postoperative care and complications” (Messner, 2019), “Tonsillectomy in adults” (Gibber, 2019), and “Anesthesia for tonsillectomy with or without adenoidectomy in children” (Sadhasivam, 2019) do not mention intra-operative and post-operative cryoanalgesia as a management option.

Prophylactic Hypothermia for the Management of Traumatic Brain Injury

Cooper and colleagues (2018) stated that after severe traumatic brain injury (TBI), induction of prophylactic hypothermia has been suggested to be neuro-protective and improve long-term neurologic outcomes.  These researchers examined the effectiveness of early prophylactic hypothermia compared with normothermic management of patients after severe TBI.  The Prophylactic Hypothermia Trial to Lessen Traumatic Brain Injury-Randomized Clinical Trial (POLAR-RCT) was a multi-center, randomized trial in 6 countries that recruited 511 patients both out-of-hospital and in emergency departments (EDs) after severe TBI.  The first patient was enrolled on December 5, 2010, and the last on November 10, 2017.  The final date of follow-up was May 15, 2018.  There were 266 patients randomized to the prophylactic hypothermia group and 245 to normothermic management.  Prophylactic hypothermia targeted the early induction of hypothermia (33° C to 35° C) for at least 72 hours and up to 7 days if intra-cranial pressures were elevated, followed by gradual re-warming.  Normothermia targeted 37° C, using surface-cooling wraps when required.  Temperature was managed in both groups for 7 days.  All other care was at the discretion of the treating physician.  The primary outcome was favorable neurologic outcomes or independent living (Glasgow Outcome Scale-Extended score, 5 to 8 [scale range of 1 to 8]) obtained by blinded assessors 6 months after injury.  Among 511 patients who were randomized, 500 provided ongoing consent (mean age of 34.5 years [SD, 13.4]; 402 men [80.2 %]) and 466 completed the primary outcome evaluation.  Hypothermia was initiated rapidly after injury (median of 1.8 hours [inter-quartile range [IQR], 1.0 to 2.7 hours]) and re-warming occurred slowly (median of 22.5 hours [IQR, 16 to 27 hours]).  Favorable outcomes (Glasgow Outcome Scale-Extended score, 5 to 8) at 6 months occurred in 117 patients (48.8 %) in the hypothermia group and 111 (49.1 %) in the normothermia group (risk difference, 0.4 % [95 % confidence interval [CI]: -9.4 % to 8.7 %]; relative risk (RR) with hypothermia, 0.99 [95 % CI: 0.82 to 1.19]; p = 0.94).  In the hypothermia and normothermia groups, the rates of pneumonia were 55.0 % versus 51.3 %, respectively, and rates of increased intra-cranial bleeding were 18.1 % versus 15.4 %, respectively.  The authors concluded that among patients with severe TBI, early prophylactic hypothermia compared with normothermia did not improve neurologic outcomes at 6 months.  These findings did not support the use of early prophylactic hypothermia for patients with severe TBI.

Guidelines on management of severe traumatic brain injury from the Brain Injury Foundation (Carney, et al., 2017) concluded that early (within 2.5 hours), short-term (48 hours post-injury) prophylactic hypothermia is not recommended to improve outcomes in patients with diffuse injury.

Therapeutic Hypothermia for the Treatment of Hemorrhagic Stroke

Choi and associates (2017) noted that therapeutic hypothermia (TH) improves the neurological outcome in patients after cardiac arrest and neonatal hypoxic brain injury.  In a pilot study, these researchers studied the safety and feasibility of mild TH in patients with poor-grade subarachnoid hemorrhage (SAH) after successful treatment.  Patients were allocated randomly to either the TH group (34.5° C) or control group after successful clipping or coil embolization.  A total of 11 patients received TH for 48 hours followed by 48 hours of slow re-warming.  Vasospasm, delayed cerebral ischemia (DCI), functional outcome, mortality, and safety profiles were compared between groups.  These investigators enrolled 22 patients with poor-grade SAH (Hunt & Hess Scale 4, 5 and modified Fisher Scale 3, 4).  In the TH group, 10 of 11 (90.9 %) patients had a core body temperature of less than 36° C for greater than 95 % of the 48-hour treatment period.  Fewer patients in the TH than control group (n = 11, each) had symptomatic vasospasms (18.1 % versus 36.4 %, respectively) and DCI (36.3 % versus 45.6 %, respectively), but these differences were not statistically significant.  At 3 months, 54.5 % of the TH group had a good-to-moderate functional outcome (0 to 3 on the modified Rankin Scale [mRS]) compared with 9.0 % in the control group (p = 0.089).  Mortality at 1 month was 36.3 % in the control group compared with 0.0 % in the TH group (p = 0.090).  the authors concluded that mild TH was feasible and could be safely used in patients with poor-grade SAH.  Furthermore, it may reduce the risk of vasospasm and DCI, improving the functional outcomes and reducing mortality.  Moreover, these researchers stated that larger randomized controlled studies should be conducted to determine the safety and clinical impact of TH in poor-grade SAH patients following successful intervention.

The authors stated that this study had several drawbacks.  First, this was a pilot study and should be interpreted with caution.  Second, the observed clinical benefits of hypothermia were limited because of the small sample size (n = 11).  A larger sample size may be needed to identify a meaningful difference between TH and control groups.  Third, despite well-designed neuro-critical care treatment guidelines, a hidden bias may exist between TH and control groups in critical care because the treating physicians were not double-blinded.  Fourth, the induction time of TH was confined after successful intervention.  Fifth, the different use of cooling devices was not reflected in TH group.

Yao and colleagues (2018) stated that TH has shown good results in experimental models of hemorrhagic stroke.  The clinical application of TH, however, remains controversial, since reports regarding its therapeutic effect were inconsistent.  These researchers conducted a systematic review based on PRISMA comparing TH with a control group in terms of mortality, poor outcome, DCI, and specific complications.  The subgroup analyses were stratified by study type, country, mean age, hemorrhage type, cooling method, treatment duration, rewarming velocity, and follow-up time.  A total of 9 studies were included, most of which were of moderate quality.  The overall effect demonstrated insignificant differences in mortality (risk ratio [RR] 0.78; 95 % CI: 0.58 to 1.06; p = 0.11) and poor outcome rate (RR 0.89; 95 % CI: 0.70 to 1.12; p = 0.32) between TH and the control group.  However, sensitivity analyses, after omitting 1 study, achieved a statistically significant difference in poor outcome favoring TH.  Moreover, in the subgroup analyses, the results derived from randomized studies revealed that TH significantly reduced poor outcomes (RR 0.40; 95 % CI: 0.22 to 0.74; p = 0.003).  In addition, TH significantly reduced DCI compared with control (RR 0.61; 95 % CI: 0.40 to 0.93; p = 0.02).  The incidence of specific complications (re-bleeding, pneumonia, sepsis, arrhythmia, and hydrocephalus) between the 2 groups were comparable and did not reach significant difference.  The authors concluded that the overall effect showed TH did not significantly reduce mortality and poor outcomes but led to a decreased incidence of DCI.  Compared with control, TH resulted in comparable incidences of specific complications.

Appendix

Selection Criteria of Cryoanalgesia for Trigeminal Neuralgia

1. Members have experienced pain for at least 6 months, and 

2. Members have tried and failed pharmacotherapies (e.g., baclofen, carbamazepine, phenytoin), or are unable to tolerate the side effects of the medication. 

Repeat cryoanalgesia may be medically necessary every 6 months.

The above policy is based on the following references: