Description of postoperative complications and bacterial contamination of wound soaker catheters used to administer postoperative local analgesia after mastectomy in 11 dogs: case series

Veterinary Research Communications https://doi.org/10.1007/s11259-024-10377-1 BRIEF REPORT Description of postoperative complications and bacterial contamination of wound soaker catheters used to administer postoperative local analgesia after mastectomy in 11 dogs: case series María Suárez-Redondo1 · Manuel Fuertes-Recuero1,2 · Alba Guzmán-Soltero1 · Delia Aguado3 María del Carmen Martín-Espada4 · Jorge Espinel-Rupérez5 · Gustavo Ortiz-Diez1,3 · Received: 17 December 2023 / Accepted: 11 April 2024 © The Author(s) 2024 Abstract Mastectomy is a common and painful procedure in dogs. Wound soaker catheters (WSC) are frequently used to reduce postoperative pain, including pain after mastectomy. The objectives of this case series were to describe the use of WSC for owner administration of postoperative local analgesia in dogs with mammary tumors treated surgically, to identify complications associated with WSC and to determine the frequency of bacterial colonization of the catheters. Twelve WSC were placed in 11 dogs during mastectomy surgery, left in place for three days, protected by a dressing and successfully managed by owners at home. No postoperative antibiotics were administered. No complications were identified in any cases. No bacterial growth was identified on bacteriological analysis of the twelve WSC. These results suggest that the use of WSC is a safe alternative for postoperative analgesia administration following mastectomy in dogs. Future studies comparing dogs with or without WSC with a larger number of dogs are needed to further evaluate efficacy and complications. Keywords Local anesthetic · Wound soaker catheters · Mastectomy · Complications · Bacterial contamination Introduction Canine mammary tumours are the most common neoplasms in female dogs and surgical resection, such as regional or radical mastectomy, is the treatment of choice in most Manuel Fuertes-Recuero 1 Complutense Veterinary Teaching Hospital, Complutense University of Madrid, Avda. Puerta de Hierro s/n, Madrid 28040, Spain 2 Department of Physiology, College of Veterinary Medicine, Complutense University of Madrid, Avda. Puerta de Hierro s/n, Madrid 28040, Spain 3 Department of Animal Medicine and Surgery, College of Veterinary Medicine, Complutense University of Madrid, Avda. Puerta de Hierro s/n, Madrid 28040, Spain 4 Department of Animal Health, College of Veterinary Medicine, Complutense University of Madrid, Avda. Puerta de Hierro s/n, Madrid 28040, Spain 5 School of Veterinary Medicine, Murdoch University, Perth, WA 6150, Australia (Rasotto et al. 2017). Described postoperative complications following mastectomy include inflammation, hemorrhage, seroma, infection, dehiscence, and postoperative pain (Horta et al. 2015; Evans et al. 2021; Spare et al. 2021). Acute postoperative pain has been associated with a broad range of negative consequences, including prolonged recovery time, decreased food intake, increased medical costs, and increased morbidity and mortality (Gan 2017). Therefore, it is essential to provide effective analgesia during the postoperative period to improve the clinical outcome of patients (Bonnet and Marret 2005). In many cases, drugs from different analgesic classes are used in combination as part of a multimodal plan.”(Bonnet and Marret 2005). Subcutaneous infiltration with continuous local anesthetic administration through wound soaker catheters (WSC) as a part of the postoperative multimodal analgesic plan has been described in human and veterinary medicine. In small animals, WSC have been reported to control postoperative pain following limb amputation (Abelson et al. 2009; Raske et al. 2015), total ear canal ablation (Radlinsky et al. 2005; Wolfe et al. 2006), and muscle dissection in dogs (Hardie et al. 2011), and fibrosarcoma resection in 13 Veterinary Research Communications cats (Davis et al. 2007; Kazmir-Lysak et al. 2023). Despite their potential benefits, WSC have only been described in 3 dogs following mastectomy procedures (Moreno Velásquez et al. 2019; Evans et al. 2021). Lidocaine and bupivacaine are the most commonly administered drugs delivered through WSC (Abelson et al. 2009). Described complications associated with WSC include: disconnection of the continuous infusion catheter (Radlinsky et al. 2005), premature catheter removal by the patient (Wolfe et al. 2006), catheter occlusion (Wolfe et al. 2006), seroma (Wolfe et al. 2006), surgical site infection (SSI) (Abelson et al. 2009) and suspected lidocaine neurotoxicity (Abelson et al. 2009). Potential complications associated with other wound catheters (closed drains) include increased wound drainage, delayed wound healing and increased SSI risk (Lu and Wright 2023). Therefore, similar complications could be expected with the use of WSC. However, none of these complications have been described associated with WSC in human or veterinary medicine. Moreover, no association between WSC and increased SSI risk has been described in veterinary medicine (Abelson et al. 2009). To the authors´ knowledge, no previous studies have evaluated the bacterial contamination of WSC used in mastectomies in small animals. The objectives of this case series were to describe the use of WSC to administer postoperative local analgesia by the owners in dogs with mammary tumors managed with mastectomy, to identify complications associated with WSC and to determine the frequency of bacterial colonization of the catheters. Materials and methods Animal The study protocol was approved by the Institutional Ethics Committee (ref.07/2017). Owner consent was obtained. Inclusion criteria included neutered female dogs with mammary tumors treated with a regional or radical unilateral mastectomy. Exclusion criteria included abnormalities on the preoperative physical examination or blood analysis; diagnoses of distant metastatic disease; or follow-up for less than 30 days. Perioperative investigation and tumor staging consisted of complete physical examination, including palpation of each mammary gland and lymph nodes, hematology analysis, serum biochemical analysis, and thoracic radiographs. Radical mastectomy was performed when lesions > 3 cm or multiple nodules were present in the cranial and caudal glands. 13 Surgical procedure and placement of WSC Dogs were premedicated with 30 µg/kg acepromazine (10 mg/ml; Neosan®) and 0.3 mg/kg methadone (10 mg/ ml; Semfortan®) intramuscularly. Anesthesia was induced with alfaxalone (10 mg/ml; Alfaxan®) and maintained with isoflurane vaporized in oxygen (IsoVet®). Intraoperative rescue analgesia was provided with fentanyl (2 µg/kg; Fentanest®) IV, if mean arterial pressure or HR increased more than 20% from its previous values within one minute. Meloxicam (0.2 mg/kg, IV, Metacam® 1.5 mg/ml) was administered after surgery. The surgical area was clipped and aseptically prepared. Prophylactic intravenous antibiotic (cefazolin 22 mg/kg; Cephacare®) was administered at the (...truncated)