The number and complexity of surgical procedures performed on an outpatient basis has been increasing as hospital admissions have been decreasing in recent years. Postoperative pain, nausea, and vomiting are the most frequent complications associated with delays in hospital discharge and unplanned admission following ambulatory surgery. In addition, patients who have had procedures frequently experience moderate to severe pain at home that cannot be controlled by prescription oral opioids: therefore, a postoperative infusion pump may be considered to control the patient’s pain. Some infusion pumps are designed mainly for stationary use at a patient’s bedside. Others, called ambulatory infusion pumps, are designed to be portable or wearable.
An infusion pump is a medical device that delivers fluids, such as nutrients and medications, into a patient’s body in controlled amounts. Infusion pumps are also utilized to deliver antibiotics, chemotherapy drugs, and pain relievers. Infusion pumps are in widespread use in clinical settings such as hospitals, and in the home environment. Infusion pumps offer advantages over manual administration of fluids, including the ability to deliver fluids in very small volumes, and the ability to deliver fluids at precise rates or automated intervals (1)
Different types of infusion pumps have different fluid-control mechanisms, which may be powered electrically or mechanically. Some infusion pumps are operated by a trained user, who programs the rate and duration of fluid delivery. In a syringe infusion pump, for example, fluid is held in the reservoir of a syringe, and a moveable piston controls fluid delivery. In a peristaltic pump, a set of rollers pinches down on a length of flexible tubing, pushing fluid forward. Some complex infusion pumps are capable of delivering fluids from multiple reservoirs at multiple rates. (1)
Anesthetic agents can be delivered directly into the skin incision site or wound bed, intra-articular or intrabursal sites (e.g., knee or shoulder), or bone wounds (e.g., iliac crest graft sites). Anesthetic drug delivery can be regulated through the use of simple disposable elastomeric pumps, filled with anesthetic agents, such as Ropivacaine or Bupivacaine, and attached to a catheter that provides continuous delivery of the drug to the desired site at a very low infusion rate. In an elastomeric infusion pump, fluid is held in a stretchable balloon reservoir, and pressure from the elastic walls of the balloon drives fluid delivery. The catheters have multiple openings similar to a “soaker hose” that allows the drug to seep into the wound along its length. These pumps are designed to deliver drugs for up to five days followed by the removal of the catheter. Some of these pumps also allow patient-controlled boluses when needed. (2)