| JOURNAL HOME | CME HOME | THIS MONTH | PAST ISSUES | ETOC | COLLECTIONS |
| AUTHORS | REVIEWERS | EDITORIAL BOARD | FEEDBACK | RSS | HELP |
| ||||||||||||||
| ||||||||||||||
|
|
|
|
||||||||||||
|
||||||||||||||
Department of Anesthesiology, Clinique Générale, Annecy, France
To the Editor:
I have read with great interest the recent article by Jankowski et al. (1). There is no doubt that the main interest of regional anesthetic techniques is to provide surgical anesthesia without excessive sedation. In some cases, it is obvious that mild sedation can improve patient comfort by decreasing anxiety. In this study, some patients receiving spinal anesthesia or psoas block (how many?) were also given an additional sedation with propofol (10–50 µm · mL–1). Furthermore, 18 patients among the 19 who received a psoas compartment block required large doses of intraoperative fentanyl. What was the sedation level in both spinal and psoas groups? The difference between sedation and general anesthesia is thin and rather difficult to clearly define and also that deep sedation is sometimes very close to general anesthesia. Thus, their definition of a failed spinal or psoas block (i.e., conversion to general anesthesia) is not accurate. Perhaps, the authors should have excluded all the patients requiring propofol or fentanyl from the definitive analysis. In addition, it is possible that such a sedation could have impaired the ability to ambulate and to leave the hospital, notably in psoas group patients.
When a regional anesthetic technique requires such doses of opioids (201 ± 69 µg of fentanyl) to work, should its efficiency as a sole technique of anesthesia be questioned? In my opinion, the only way of obtaining a complete block of the knee is to combine both sacral (sciatic block) and lumbar (psoas block or combined femoral/obturator nerve blocks) plexus blocks. Why did the authors not perform a sciatic nerve block in combination with the psoas compartment block?
Reference
Assistant Professor of Anesthesiology Professor of Anesthesiology, Mayo Clinic College of Medicine, Rochester, MN
In Response:
We appreciate Dr. Souron’s interest in our study and welcome the opportunity to respond to his comments.
Dr. Souron questioned the efficacy of psoas compartment block and spinal anesthesia for outpatient knee arthroscopy due to the administration of intraoperative fentanyl and propofol. However, according to our methodology, a single 2–3 µg/kg fentanyl dose was administered prior to surgical incision (during block performance). In addition, intraoperative sedation was achieved with a propofol infusion of 10–50 µg/kg/min. If more than 50 µg/kg/min of propofol was required, the block was considered a failure (1). These doses are consistent with those administered during "conscious sedation" in which patients remain arousable to voice, with adequate spontaneous respiration and protective airway reflexes intact. Furthermore, in many institutions, including ours, it is a patient expectation that intraoperative sedation be provided.
The importance of adequate perioperative sedation during regional anesthesia should not be minimized. Fanelli et al. (2) reported that despite a 93% success rate for upper and lower peripheral techniques using a nerve stimulator, 26% would not request the same anesthetic procedure in the future, mainly because of discomfort during block placement. Patient acceptance was lowest among those undergoing a combined sciatic-femoral block. As a result, the authors advocated the use of analgesic medications during block performance (2). Conversely, with the use of conscious sedation as an adjunct to regional anesthesia, we found a high level of patient satisfaction.
We disagree that the use of sedation may have delayed ambulation and prolonged hospital stay in patients receiving regional anesthesia. If this were the case, one would expect that times to ambulation and discharge would be prolonged in patients receiving general anesthesia since they received the most "sedation." However, we did not note a difference in these variables among the groups.
Dr. Souron also queried why complete unilateral anesthesia was not attempted through a combined sciatic-psoas technique. Although somewhat controversial, it has not been accepted that a sciatic block is required for postoperative analgesia following total knee replacement (3). Therefore, it is unlikely to be a critical component of anesthesia for a comparatively minor procedure such as knee arthroscopy.
It is important to note that our results may not be directly applicable to other institutions. The optimal technique for knee arthroscopy will depend upon surgical duration, patient expectations and preferences, and nursing practices. These must all be taken into consideration when selecting an anesthetic approach.
References
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
|
