Incidence and Predictors of Neuropathic Pain Following Breast Surgery

Purpose

Neuropathic pain (NPP) following breast surgery extends morbidity in the postoperative period. The incidence and etiology of postoperative NPP remains unclear and under-reported in literature. This study aims to define the incidence of neuropathic pain following breast surgery and to identify patient characteristics that are predictors for developing postoperative NPP.

Methods

Consecutive female patients undergoing breast resection surgery over a 5-year period (2008–2012) with 1-year minimum follow-up were included in this single-center study. Retrospective chart review was performed to identify patient specific characteristics including the development of post-operative NPP. Data was analyzed using univariate and multivariate logistic regression.

Results

A total of 470 patients were identified for study inclusion. The incidence of postoperative NPP was 14.7 % (69 of 470). Significant predictors for the development of postoperative NPP in the univariate analyses included history of diabetes mellitus, diabetic neuropathy, or fibromyalgia, concomitant axillary surgery, axillary node dissection, and taxane-based chemotherapy regimen. Multivariate analysis identified African American race [odds ratio (OR) = 1.78; 95 % CI = 1.01–3.17; p = 0.05), history of diabetes mellitus (OR = 1.98; 95 % CI = 1.0–3.74; p = 0.01) or fibromyalgia (OR = 2.75; 95 % CI = 1.13–6.69; p = 0.03), and taxane-based chemotherapy regimen (OR = 2.85; 95 % CI = 1.23–6.58; p = 0.01) as being independently associated with the development of postoperative NPP.

Conclusions

NPP is a significant risk following breast surgery. African American race, history of either diabetes mellitus or fibromyalgia, and treatment with taxane-based chemotherapy regimens are all associated with an increased risk of NPP.     

The Incidence of Complications Is Low Following Foot and Ankle Surgery for Which Peripheral Nerve Blocks Are Used for Postoperative Pain Management

Background

The incidence of neurologic complications from foot and ankle surgery utilizing regional anesthesia is not well established.

Questions/Purposes

The purpose of this study was to prospectively determine the incidence of neurologic and peripheral nerve block (PNB) site complications on a busy foot and ankle service that utilizes ankle blocks (ABs) and popliteal blocks (POPs).

Patients and Methods

This prospective observational study included patients undergoing foot and ankle surgery with ABs or POPs. Block choice was determined by surgeon’s preference. Patients were assessed for complications during postoperative visits at 2, 6, and 12 weeks. The relation of each complication to the block was scored by a surgeon and anesthesiologist.

Results

From October 2012 to October 2014, 2516 patients underwent 2704 surgeries. There were 195 complications (7.2%) considered neurologic or at the PNB site. The incidence of serious complications was 0.7%. A higher complication rate was reported for POPs (8.8%) than for ABs (2.5%). However, when analysis was limited to forefoot surgery, this difference was not significant. Dexamethasone use was associated with increased complications for POPs. Only 5 of the 195 total complications, and 2 of 20 serious complications, were deemed to have been likely caused by the block by both the surgeon and anesthesiologist reviewer.

Conclusions

The incidences of neurologic or block-related complications and serious complications were 7.2 and 0.7%, respectively, most without a clear surgical vs. nerve block etiology. The higher complication rate for POPs using perineural dexamethasone should be interpreted cautiously in light of the lack of randomization and likely confounders.

     

Preincisional Dextromethorphan Treatment for Postoperative Pain Management after Upper Abdominal Surgery

Previous studies showed that ketamine, an N-methyl-d-aspartate (NMDA) receptor antagonist, provides a preemptive analgesic effect and preemptive analgesia improves postoperative pain management. The aim of this study was to examine whether premedication with dextromethorphan (DM) improves postoperative pain management after upper abdominal surgery. Sixty (American Society of Anesthesiologists class 1 and 2 of either gender) patients scheduled for upper abdominal surgery were included in the study. Patients were randomly assigned to one of four groups: control, DM-10, DM-20, and DM-40. In the control group, chlorpheniramine maleate (CPM, 20 mg) was injected immediately before induction of anesthesia intramuscularly (IM). In the DM-10, DM-20, and DM-40 groups, patients were premedicated with DM 10 mg, 20 mg, and 40 mg IM, respectively. After operation, patient-controlled analgesia (PCA) with morphine was given for pain relief. The time to the first PCA trigger, morphine consumption, pain scores, and analgesic-related side effects were recorded at 1, 2, 4, 24, 48, and 72 hours after surgery. The time to first PCA trigger for the control group was 17.8 ± 1.4 minutes, for group DM-10 20.2 ± 1.6 minutes, for group DM-20 32.4 ± 1.9 minutes, and for DM-40 77.9 ± 6.5 minutes. The morphine delivered and PCA triggering frequency were 5.5 ± 0.5/11.3 ± 0.8 times for the controls, 5.5 ± 0.4/14.1 ± 1.3 times for DM-10, 3.1 ± 0.3/6.3 ± 1.2 times for DM-20, and 0.2 ± 0.1/0.3 ± 0.2 times for DM-40 during the first hour after operation. For the first day, the figures are 19.9 ± 1.2/23.9 ± 1.4 for the controls, 15.6 ± 1.2/17.3 ± 2.4 for DM-10, 12.6 ± 0.7/15.9 ± 1.6 for DM-20, and 5.0 ± 0.21/5.6 ± 0.9 for DM-40. On the first day, the cough pain scores were 6.67 ± 0.23, 6.53 ± 0.16, 6.67 ± 0.23, and 5.73 ± 0.18 for the controls, DM-10, DM-20, and DM-40 groups, respectively. All data showed dose-dependent better pain relief in DM-premedicated patients. We conclude that DM premedication offers preemptive analgesia and reduces postoperative pain and morphine requirement.