Ms. G was a healthy 23-year-old with a history of a verrucous lesion in the web space of the ring and middle fingers of her left hand. She had treated the lesion on her own with multiple OTC products without success. She was seen by her primary-care physician (PCP) and requested the lesion be “frozen.” After properly counseling the patient on the risks and benefits of the procedure, the PCP applied liquid nitrogen cryotherapy to the lesion. Ms. G noted, “the spray went all over the skin around the wart.” The day after the procedure, she developed a large bullous lesion in the web space of the ring and middle fingers. She also had moderate pain around the lesion and increased pain when trying to grasp an object. Ms. G stated that she “popped the blister and drained the fluid.” The following day, the patient returned to her primary-care clinic for treatment of increasing pain, redness, and swelling of the ring and middle fingers, as well as the dorsal left hand. Her provider (not the original PCP) contacted our orthopedic on-call physician requesting a same-day consult for possible tenosynovitis. We were informed that an aerobic wound culture had been taken during the visit.
1. PHYSICAL EXAMINATION
Ms. G was well-developed, well-nourished, not ill-appearing, and in mild distress. She was afebrile and reported no nausea, vomiting, chills, or body aches. Examination of the patient’s left hand revealed a 3- x 5-cm area of induration and erythema of the volar and dorsal aspects of the middle/ring finger web space with serous, nonpurulent discharge. A 3- x 3-mm necrotic area on the radial side of the ring finger was also noted. The wound bed in the web space was white in appearance (Figure 1). The patient’s distal capillary refill was less than two seconds. She had diffuse tenderness to palpation of the proximal phalanges and the extensor surface of the hand. The volar surface of the hand was slightly erythematous with no Kanavel’s signs. Ms. G was able to partially close her fist, an action that caused tightness in both fingers and the dorsum of the hand. There was no palpable lymphadenopathy of the epitrochelar area of the elbow or axillary region.
Lab results previously drawn by the PCP showed WBC 12,000/μl with no left shift, elevated C-reactive protein (CRP) (7.8 mg/L), and elevated erythrocyte sedimentation rate (ESR) (47 mm/hour). After discussion with the supervising orthopedic surgeon, a decision was made to place the patient in a protective dressing and volar splint, start her on oral clindamycin, and advise elevation and rest of the extremity. We instructed Ms. G to return the following morning for reassessment. The area of induration was clearly marked. She was also instructed not to eat or drink after midnight.
The next morning, Ms. G reported increased pain in the hand with no fever, chills, or night sweat. The area of induration had grown, tenderness to palpation had worsened, and passive or active flexion of the ring/middle fingers caused moderate pain (Figure 2). The patient was taken to the operating room for incision/drainage and wound exploration.
2. OPERATIVE FINDINGS
A 3-cm incision was made over the dorsal surface of the patient’s left hand, just proximal to the wound in the web space. After dissection through subcutaneous tissue, a space was created to pass a freer elevator to probe the dorsal and volar aspects of the hand. A serous fluid collection was drained, but no gross purulence or evidence of abscess was found. Intra-operative aerobic and anaerobic cultures were taken, and the hand was then copiously irrigated with saline solution. A Penrose drain was placed, and the wound was closed with simple, interrupted polypropylene sutures. After a sterile dressing and a volar splint were placed, the patient was admitted for observation, pain control, and IV antibiotics.
Ms. G remained in the hospital for 48 hours on IV vancomycin. The aerobic wound culture taken on day one was positive for group A Streptococcus (S. pyogenes), sensitive to penicillins. The patient showed clinical improvement within 24 hours. Lab results on the day of discharge showed WBC 6,200/μl, CRP 2.2 mg/L, and ESR 18 mm/hr. Ms. G was discharged on amoxicillin 500 mg, pain medications, and instructions to rest the extremity. Her one-week (Figure 3) and two-week follow-up visits showed good healing and granulation of the wound area. She reported no pain with her activities of daily living. At her final visit four weeks postoperatively (Figure 4), there was no pain, paresthesia, or loss of function in the left hand.
Liquid nitrogen therapy/cryosurgery has been proven safe, reliable, and effective for the treatment of verrucae, seborrheic keratoses, and actinic keratoses. The complications of cryosurgery are rare but can cause significant morbidity. Reactions to cryotherapy vary widely and can include hemorrhage, severe systemic reactions in cold-sensitive patients, full-thickness skin necrosis, nerve damage, and tissue defects.
Technical problems primarily involve the delivery system and temperature monitoring at the time of treatment. It is important to remember that liquid nitrogen is -473° F. Ensure that the delivery system is in good working order, and direct the spray can onto the lesion rather than the surrounding skin. In Ms. G’s case, it was discovered that the spray nozzle on the canister was defective, resulting in a large spray area instead of directed spray.
Normal responses to cryotherapy include redness, pain, swelling, and bullous lesions. The patient must be instructed in proper skin care, especially in the case of bullous lesions. The risk of cellulitis is higher if bullous lesions and/or open wounds develop. Site selection in this case (web space) contributed to maceration and skin compromise, which ultimately lead to the cellulitis.
The most serious complication of cryosurgery is nerve damage. Special care must be taken around areas in which nerves are superficial, including the sides of the fingers. Anesthesias or parasthesias are usually temporary but may last for many months.
Ms. G’s complication involved extensive tissue destruction due to inadequate equipment and inadequate tissue temperature monitoring. Site selection, monitoring of skin temperature, and knowledge of the technical aspect of the delivery system will help prevent iatrogenic injury when using liquid nitrogen.
Mr. Spivey is a physician assistant in the orthopedic clinic of the Carl R. Darnall Army Medical Center in Fort Hood, Tex.
- Elton RF. Complications of cutaneous cryosurgery. J Am Acad Dermatol. 1983;8:513-519.