We performed successful management of breast surgery using Pecs II block, TTP block, and sedation with dexmedetomidine in a patient with achondroplasia. This shows that the combination of Pecs II and TTP blocks with intravenous dexmedetomidine can be an alternative to general anesthesia and neuraxial anesthesia in patients who have difficulties with them.
Patients with achondroplasia have potential problems for both general anesthesia and neuraxial anesthesia. For general anesthesia, difficult airway associated with obstructive sleep apnea, atlantoaxial instability, and adenotonsillar hypertrophy can be a problem. Some investigators have reported difficult airway in patients with achondroplasia [8, 9]. The strategy of airway management should be planned for individual patients because achondroplasia causes deformities in various parts of the airway and its severity may vary widely according to patients. We planned to avoid the use of general anesthesia, considering the feasibility of management with peripheral nerve blocks and sedation and the risk of general anesthesia for respiratory and cardiac functions and potential airway difficulties in the patient. Epidural anesthesia or thoracic paravertebral block can be used for pain relief in breast surgery [10, 11]. However, spinal abnormalities in patients with achondroplasia can make neuraxial anesthesia or deep peripheral nerve block difficult. Therefore, we decided to use the combination of truncal regional anesthesia and intravenous dexmedetomidine. Pecs I block targets the lateral and medial pectoral nerves and blocks the lateral mammary area , whereas Pecs II block targets the intercostobrachial, long thoracic, and multiple upper intercostal nerves and produces sensory loss in the axillary region in addition to the area affected by Pecs I block . Although Pecs I and Pecs II blocks cannot block the inner region of the breast, TTP block targets multiple anterior branches of the intercostal nerves and blocks the internal mammary area . These peripheral nerve blocks have the following advantages: they can target relatively superficial regions and there is no need to change the patient’s position. Because of these advantages, the use of superficial peripheral nerve blocks, such as Pecs II or TTP blocks, may be prudent for patients with achondroplasia as shown in this report.
In breast surgery, epidural anesthesia or thoracic paravertebral block without general anesthesia have been reported as good analgesia . In contrast, reports on the combination of Pecs II and TTP blocks without general anesthesia are limited. Ueshima et al. have reported Pecs II and TTP blocks without general anesthesia for the segmental upper outer region of the left breast in an 86-year-old patient with low cardiac function . Thereafter, they reported bilateral Pecs II and TTP blocks without general anesthesia for bilateral breast resection in a patient with severe obstructive pulmonary disease . Kim et al. have reported Pecs II block and internal intercostal plane block without general anesthesia for a huge breast fibroadenoma resection in a patient with fear for general anesthesia . Hong et al. have reported modified Pecs II block (below the serratus muscle as the second injection) and pecto-intercostal fascial block without general anesthesia for partial resection of recurrent breast cancer in a parturient . Compared with these reports, our case was challenging in terms of determining the dose of local anesthetics because the body weight of the patient was only 30 kg. According to these previous reports, Pecs II block requires 10 and 20 mL of local anesthetics for the shallower and deeper plane, respectively, and TTP block requires 10–15 mL of local anesthetics. Therefore, we considered to use a total of 40–45 mL of local anesthetics. As the body weight of our patient was 30 kg, we could administer up to 36 or 45 mL of 0.25% levobupivacaine or 0.2% levobupivacaine, respectively, considering the maximum dose of 3 mg/kg. A total of 36 mL of 0.25% levobupivacaine was considered because we believed that a lower concentration would be inadequate without general anesthesia management. Thus, the dose of local anesthetics was reduced for the lower region of the breast. Sensory loss around the incisional area at the right upper breast and axilla region was confirmed, and intraoperative management was successfully performed without any additional analgesics.
In summary, we report the successful management of breast surgery in a patient with achondroplasia using Pecs II block, TTP block, and sedation with dexmedetomidine. The combination of peripheral nerve blocks is a useful option in patients who have difficulties with both general anesthesia and neuraxial anesthesia.