Could Wound Instillation Provide an Efficient Analgesia Comparable to That Provided by PECS-II Block for Modified Radical Mastectomy Using Ketamine–Bupivacaine Combination? A Pilot Study

Ahmad M Abd El-Rahman,1 Saif Eldeen Gamal Khalaf,1 Mohamed H Bakri2 1Department of Anaesthesia, Pain, and ICU, South Egypt Cancer Institute, Assiut University, Assiut, Egypt; 2Department of Anaesthesia, Pain, and ICU, Faculty of Medicine, Assiut University, Assiut, EgyptCorrespondence: Ahmad M Abd El-Rahman, Department of Anaesthesia, Pain, and ICU, South Egypt Cancer Institute, Assiut University, Assiut, Egypt.South Egypt Cancer Institute, Assiut University, El-Mithaq Street, Mansheit Al Omara, Assiut City, Assiut, Egypt, Tel +201149606060, Fax +20882348609, Email [email protected] and Aim: In the light of the abundance of various analgesic methods available for analgesia following modified radical mastectomy (MRM) (pharmacological or interventional), we aimed to try a very simple technique using a drug combination (ketamine–bupivacaine) through wound instillation and to compare it to the reputable PECS-II block using the same drug combination. We hypothesized that, with this drug combination, local instillation may achieve a comparable, long lasting, analgesia for almost 48 hours, with less costly, and simple method.Patients and Methods: Sixty women scheduled to undergo MRM participated in this study. Patients were randomized to have either; ultrasound-guided, modified PECS block (PECS group), or instillation of analgesics into the surgical wound (local instillation group). In both groups, we used 1 mg/kg ketamine HCL plus 0.25% bupivacaine HCL in a 30 mL volume. Total consumption of rescue morphine, time to 1st analgesic request, numerical rating scale (NRS), hemodynamic effects were recorded over 48 hours postoperatively. In addition, the time required to perform either technique and possible side effects were recorded.Results: Total consumption of rescue morphine, first analgesic request, pain scores, showed no statistically significant differences in both groups; the local instillation procedure required a statistically significant shorter time to perform than the PECS procedure. None of the groups showed significant differences in the incidence of adverse effects.Conclusion: Local wound instillation provided a comparable analgesia to PECS-II block following modified radical mastectomy. Ketamine–bupivacaine combination prolonged analgesia for almost 2 days.Keywords: PECS block, wound instillation, ketamine, bupivacaine, modified radical mastectomy