How is pain best controlled in the ambulatory patient in the PACU?

How is pain best controlled in the ambulatory patient in the PACU?

Management of postoperative pain in the PACU as well as after discharge is of major concern to the anesthesiologist. Adequate pain relief must be achieved before a patient may be discharged and patient comfort in the postoperative period is important. The prevention of postoperative pain appears much easier to accomplish than the treatment of pain that has been allowed to reach significant intensity. Unfortunately, the occasional inability to manage postoperative pain remains a cause of unexpected overnight hospitalization.

In procedures for which patients can be anticipated to experience significant postoperative discomfort, the addition of an opioid as part of the anesthetic is helpful. A propofol anesthetic will not provide postoperative analgesia. The intraoperative administration of long-acting local anesthetics such as bupivacaine, 0.25–0.5%, at the surgical site may provide hours of postoperative pain relief. This technique has proven to be most efficacious following inguinal and umbilical hernia repairs and minor breast surgery. The efficacy of intra-articular local anesthetics and opioids following arthroscopy of the knee joint has been shown to be of value. Other techniques such as per-formance of a penile block or the topical application of lidocaine jelly on the penis following circumcision have proven effective in reducing discomfort. The use of ilio-inguinal and iliohypogastric nerve blocks is efficacious in adults and children following herniorrhaphy. Repeating maxillary or mandibular nerve blocks at the conclusion of oral surgery is efficacious.

In the PACU, careful titration of small intravenous doses of opioids can safely provide satisfactory analgesia. The blood levels of opioids that are required to provide analgesia are less than those that usually result in signifi-cant respiratory depression or marked oversedation. Fentanyl is the narcotic of choice in the postoperative period for treating pain. Its duration of action is modest, and intravenous doses of 25–50 μg may be repeated every 5 minutes until satisfactory pain relief has been achieved. Medicating patients with oral opioid preparations before discharge will provide a patient with a more comfortable trip home because the intravenous drugs administered in the PACU have relatively short durations of action.

The home use of patient-controlled analgesia systems permits the discharge of patients who are expected to expe-rience pain that may not be sufficiently controlled with oral agents. Experiments with patient-controlled analgesia in the home have found this modality of pain relief to be both safe and effective. Oxycodone and codeine are suit-able for amelioration of mild-to-moderate pain but are not strong enough to prevent hospitalization in a patient who experiences severe pain.

Ketorolac, a nonsteroidal anti-inflammatory agent, has been administered orally, intramuscularly, and intravenously in an attempt to prevent and relieve pain and reduce opioid requirements. The drug itself is free of opioid-related side-effects including sedation and vomiting. Some are hesitant to employ this class of drugs because of their potential for causing bleeding. Further, when administered orally, gastric irritation may be encountered. COX-2 inhibitors minimize the potential for postoperative bleeding and the risk of gastrointestinal complications and thus are becoming popu-lar as a non-opioid adjuvant for treating postoperative pain.