Continuous Peripheral Nerve Blocks in Hospital Wards after Orthopedic Surgery

Abstract

Background: Continuous peripheral nerve block (CPNB) isthe technique of choice for postoperative analgesia after painfulorthopedic surgery. However, the incidence of neurologic andinfectious adverse events in the postoperative period are notwell established. This issue was the aim of the study.Methods: Patients scheduled to undergo orthopedic surgeryperformed with a CPNB were prospectively included during 1 yrin a multicenter study. Efficacy of postoperative analgesia, bacteriologiccultures of the catheter, and acute neurologic andinfectious adverse events were evaluated after surgery in 1,416patients at arrival in the postanesthesia care unit, at hour 1, andevery 24 h up to day 5. Risk factors for adverse events weredetermined using logistic regression.Results: The median duration of CPNB was 56 h. Both generalanesthesia and CPNB were performed in 73.6% of the patients.Postoperative analgesia was effective in 96.3%, but an increasein pain scores was noted at hour 24 (P
0.01). Hypoesthesia ornumbness occurred in 3% and 2.2%, respectively, and paresthesiaoccurred in 1.5%. Three neural lesions (0.21%) were notedafter continuous femoral nerve block. Two of these patientswere anesthetized during block procedure. Nerve damage completelyresolved 36 h to 10 weeks later. Cultures from 28.7% ofthe catheters were positive. Three percent of patients had localinflammatory signs. The bacterial species most frequentlyfound were coagulase-negative staphylococcus (61%) and gramnegativebacillus (21.6%). A Staphylococcus aureus psoasabscess (0.07%) was reported in one diabetic woman. Independentrisk factors for paresthesia/dysesthesia were postoperativemonitoring in intensive care, age less than 40 yr, and use ofbupivacaine. Risk factors for local inflammation/infection werepostoperative monitoring in intensive care, catheter durationgreater than 48 h, male sex, and absence of antibioticprophylaxis.Conclusion: CPNB is an effective technique for postoperativeanalgesia. Minor incidents and bacterial colonization of cathetersare frequent, with no adverse clinical consequences in thelarge majority of cases. Major neurologic and infectious adverseevents are rare.