| Referate engleza | Bac 2008 limba engleza| Recomanda unui prieten

Ambulatory Anesthesia

CURRENT STATUS OF REGIONAL ANESTHESIA FOR ADULT OUTPATIENTS
Dermot Fitzgibbon MB, BCh, FFARCSI

From the Department of Anesthesiology, University of Washington School of Medicine, Seattle, Washington

Address reprint requests to
Dermot Fitzgibbon, MB, BCh, FFARCSI
Department of Anesthesiology
University of Washington
School of Medicine
1959 N.E. Pacific Street
Seattle, WA 98195

BENEFITS OF REGIONAL ANESTHESIA
The challenge of anesthesia for ambulatory patients is to provide for rapid return to street readiness with the most effective postoperative analgesia and minimal undesirable side effects. Regional anesthesia, with its selective local action and relatively simple equipment, offers an excellent anesthetic choice in an outpatient facility. In addition to limiting the anesthetized area to the surgical site, the common side effects of general anesthesia (e.g., nausea, vomiting, lethargy) are reduced, the risks and side effects of endotracheal intubation are minimized, patient recovery time may be decreased, and improved analgesia is provided in the postoperative period. [7] [46]
A number of studies [51] [82] have evaluated the efficacy of ambulatory regional anesthesia. Urmey et al [82] prospectively recorded data on ambulatory surgery patients at an orthopedic speciality hospital where regional anesthesia was the first-line standard care; the various types of anesthesia administered are listed in Table 1 (Table Not Available) . Only 4.4% of patients who had regional anesthesia required admission compared with 12% of general anesthetics. Discharge times were similar for general, spinal, or epidural anesthesia (average of 3 hours); patients who had peripheral nerve blocks were discharged in approximately 2 hours. Failure of regional anesthesia, necessitating general anesthesia, occurred in only 1% of cases. The authors concluded that regional anesthesia in an ambulatory center is effective in all but a small percentage of patients. Osborne [51] evaluated outcome for 6000 consecutive procedures in a major public teaching hospital day surgery unit. Anesthesia-related complications were more frequent with general anesthesia (1:114) than with regional anesthesia (1:180) or local anesthesia plus sedation

712
TABLE 1 -- ANESTHETIC TECHNIQUES FOR AMBULATORY ORTHOPEDIC PROCEDURES
From Urmey WF, Stanton J, Sharrock NE: Initial one-year experience of a 97.3% regional anesthesia ambulatory surgery center. Reg Anesth 18:69, 1993; © Churchill Livingstone, with permission.
(Not Available)

(1:780). Recovery with regional or local anesthesia was significantly shorter than after general anesthesia.
Despite the potential advantages cited regional anesthesia should not be considered universally appropriate. Factors that contribute to a successful regional anesthetic include the appropriate selection of patients, anesthetic technique, and local anesthetic, use of sedative and hypnotic agents, and the skill of the anesthesiologist. Prior screening of patients through preanesthesia testing (PAT) clinics is very useful in determining the acceptability of patients for a regional anesthetic. Very young or excessively anxious patients may be poor candidates. Similarly, obese patients may present technical problems, especially for central neuraxial blocks. Patients of American Society of Anesthesiologists (ASA) physical status III or IV may be particularly good candidates for ambulatory regional anesthesia compared to general anesthesia, especially if their systemic diseases are medically stable.

SELECTION OF TECHNIQUE AND LOCAL ANESTHETIC
Outpatient regional techniques require some modification from standard inpatient procedures. Ideally, an outpatient regional technique should be rapid in onset and result in few if any acute or delayed complications (e.g., pneumothorax). The additional time needed to perform many regional blocks, as well as the time needed for the anesthetic to take effect, is a potential drawback when procedures are short and turnover between cases is rapid. Use of blocks that require more time than the procedure itself to perform should be limited to those situations where specifically indicated for medical reasons or the patient expresses a strong preference for a specific technique. Blocks that significantly impair the ability to ambulate and void should be tailored to the anticipated usual duration of surgery by appropriate selection of both local anesthetic agent and technique to minimize both recovery and discharge time. Prolonged analgesia from a block (e.g., foot, arm, or hand blocks) may be beneficial in some instances, particularly if the ability of the patient to perform various activities is not significantly impaired; however, prolonged anesthesia may provoke anxiety or be considered unpleasant or irritating by many patients when

713
it persists for many hours after hospital discharge and should be discussed with patients before instituting such a block.