OSE_1306_part2_Layout 1 6/3/13 3:41 PM Page 94
R E G I O N A L
A N E S T H E S I A
pump and local anesthetic reservoir) and — for ambulatory
patients — catheter removal at home. Fortunately, infusionrelated serious and lasting injuries are uncommon, and relatively
minor complications occur at a frequency similar to single-injection peripheral nerve blocks. Still, it's necessary to be knowledgeable about these potential complications.
During the perineural infusion, more-common (and benign) complications include catheter dislodgement or obstruction and fluid
leakage at the catheter site. Additional possible complications
include infusion pump malfunction, undesired pause or disconnection, skin irritation or allergic reactions to the catheter dressing
and liquid adhesive, and catheter-induced brachial plexus irritation.
In addition, a CPNB-induced insensate extremity may prove disconcerting to patients. It may impede physical therapy or ambulation, and is considered a risk factor for injury by some investigators. You can also pause the infusion pump until sensory perception begins to return, then restart the infusion at a lower basal
rate. Conversely, inadequate analgesia or breakthrough pain may
occur. They are often treated by increasing the basal infusion and
providing patient-controlled bolus doses. Give patients clear postop instructions on these topics, and have a contact person and
plan in place to handle either of these occurrences.
Perineural infusions affecting the femoral nerve correlate with
patient falls after hip and knee arthroplasty, possibly due to
CPNB-induced sensory, proprioception or quadriceps weakness.
Consider interventions that may decrease the risk of falls, such as
limiting the local anesthetic dose or mass; providing crutches or
walker and a knee immobilizer during ambulation; and educating
surgeons, nurses, and physical therapists about possible CPNB9 4
O U T PAT I E N T S U R G E R Y M A G A Z I N E O N L I N E | J U N E 2013
