Cryoanalgesia to Prevent Acute and Chronic Pain Following Nuss Procedure

Funnel chest deformation is a great challenge for therapeutic teams due to severe pain in the postoperative period as well as chronic pain. The use of many analgesic drugs, including opioids, is associated with adverse side effects, difficulties with rehabilitation, an increased risk of complications, prolonged hospitalisation, and the cost of the procedure. Cryoanalgesia as a part of multimodal analgesia along with the education and prehabilitation of the patient according to the novel original educational - training application 'Back on Feet' as well as the interdisciplinary care in accordance with the enhanced recovery after surgery (ERAS) protocol, which has a real impact on the optimisation of perioperative care.

This Before - After Study is a single institution pilot study designed to compare standard therapy (control group: regional analgesia: intrapleural or bilateral erector spine plane block) versus a novel approach (interventional group: Cryoanalgesia combined with bilateral single shot erector spine plane block) to address the need for better management of acute and long-term pain in the pediatric population diagnosed with funnel-chest and treated using the modyfied Nuss method.

First group received a standard care according to Polish guidelines. The data of control group analysed and the interdisciplinary team work protocol will be introduced to the interventional group. The interventional group was prepared according to prehabilitation with the 'Back on feet' application and perioperative ERAS protocols. The patients of interventional group received intraoperative cryoanalgesia using the Cryo-S Painless device (Metrum - Cryoflex Polska Limited) as an additional procedure to multimodal analgesia. This is the first time that the cryoanalgesia procedure was performed in children in Poland.

The aims of the study were the assessment the effectiveness of cryoanalgesia as a method of acute and long-term pain control, safety of the method and the impact of preoperative preparation according to the 'Back on Feet' program introduced as a part of ERAS protocol.

Specific Aim 1: To determine if, compared with current analgesia, the addition of cryoanalgesia decreases the incidence and severity of post-surgical pain.

Hypothesis 1a (primary): The severity of surgically-related pain was significantly decreased from postoperative day 2 with the addition of cryoanalgesia as compared with patients receiving solely standard-of-care treatment.

Hypothesis 1b: The incidence and severity of chronic pain was significantly decreased 3 months following surgery with the addition of cryoanalgesia as compared with patients receiving solely standard-of-care treatment.

Specific Aim 2: To determine if, compared with current analgesia, the addition of cryoanalgesia improves postoperative functioning.

Hypothesis 2a: Following modyfied Nuss procedure the range of motion and independence was significantly increased in the 2 postoperative day following operation with the addition of cryoanalgesia as compared with patients receiving solely standard-of-care treatment.

The results were compared in terms of demographics, pain levels, side effects of the pain relief medications in the postoperative period, quality and length of rehabilitation, patient satisfaction using the Quality of Life by modyfied Nuss questionnaire, and the total costs of hospitalization.

Inclusion criteria

• Patients undergoing pectus excavatum repair with modyfied minimal invasive thoracoscopic NUSS technique
• aged 10 years or above 10
• informed consent signed for cryoanalgesia

Exclusion criteria

• Age of 9 years or below
• Refuse to receive cryoanalgesia or regional analgesia as primary pain relief
• Any contraindication to cryoanalgesia
• Difficult follow-up for geographical reasons and/or impossibility by the patient to understand how to perform self-measurements