J Neurosurg Anesthesiol
2.
3. 4.
5.
6.
Volume 26, Number 3, July 2014
blood pressure determinations. J Neurosurg Anesthesiol. 2013;25:154–161. Schonberger RB, Burg MM, Holt NF, et al. The relationship between day-of-surgery and primary care blood pressure among Veterans presenting from home for surgery. Is there evidence for anesthesiologist-initiated blood pressure referral? Anesth Analg. 2012; 114:205–214. McKesson E. The reaction of certain circulatory conditions to anesthesia and surgery. Anesth Analg. 1923;43–49. Schonberger RB, Barash PG. Impact versus impact factor: revisiting a classic article that was never cited. Anesth Analg. 2012;115: 1286–1287. Park S-J, Park JB, Choi D-J, et al. Detection of masked hypertension and the ‘mask effect’ in patients with well-controlled office blood pressure. Circ J. 2011;75:357–365. Frieden TR, Berwick DM. The “Million Hearts” initiative—preventing heart attacks and strokes. N Engl J Med. 2011;365:e27.
Can Preoperative Betaxolol Eye Drops Reduce the Incidence of Postoperative Visual Loss (POVL)?
blinded to the results, and the person collecting the IOP measurements was blinded to which eye had received the medication. Results were unblinded at the conclusion of the study. Our modest sample size yielded an average increase in IOP of 117% in the control group compared with 93% in the betaxolol group. The mean prone duration was 5.5 hours. Although the overall results were not statistically significant, we did encounter one study patient who seemed to have a more profound effect. A middle-aged patient underwent complex spine surgery and was lying prone for 11 hours. Blood loss was 3500 mL, and he received a total of 7 L of crystalloid, 2 L of colloid, and 2 units of packed cells. The saline control eye saw an increase in IOP from 7 to 43, whereas the betaxololtreated eye went from 10 to 20. We bring this case to the reader’s attention as it suggests a possible protective effect of betaxolol administration preoperatively for prevention of IOP increase in patients at risk for POVL.
Karl Zheng, MD John G. Brock-Utne, MD, PhD
To the Editor: Recently, we completed a study on a patient in a clinical study entitled: Does the use of Betaxolol prevent the potential increase in intraocular pressure in anesthetized patients in the prone position? We believe that this one case, in particular, in our study group of 10 patients illustrates the potential benefit of betaxolol in the possible prevention of postoperative visual loss (POVL). In our study, betaxolol (0.5%) eye drops were administered in the preoperative holding area to one eye randomly, with the other eye receiving a saline drop. We then used a Reichert Tono-Pen XL (Buffalo, NY) to measure intraocular pressure (IOP) in both the eyes at the beginning of the case following intubation and at the end of the case before extubation. The person administering the eye drops was
To JNA Readers: Selective scalp nerve block is a technique which has been increasingly
The authors have no funding or conflicts of interest to disclose.
The authors have no funding or conflicts of interest to disclose.
r
2014 Lippincott Williams & Wilkins
Department of Anesthesiology Perioperative and Pain Medicine Stanford University School of Medicine Stanford CA
A Modified Technique for Auriculotemporal Nerve Blockade When Performing Selective Scalp Nerve Block for Craniotomy
Correspondence
used as a surgical anesthetic before awake craniotomy and to decrease analgesic requirements after craniotomy performed under general anesthesia.1 As described by Pinosky et al in 1996,2 6 nerves (4 branches of the trigeminal nerve and the anterior and posterior rami of C2) are identified by landmarks on each side of the cranium (supratrochlear, supraorbital, zygomaticotemporal, auriculotemporal, lesser occipital, and greater occipital nerves) and subsequently infiltrated with volumes of local anesthetic ranging from 2 to 5 mL. A seemingly rare complication of auriculotemporal nerve blockade is inadvertent blockade of the adjacent facial nerve. However, 2 of the authors recently reported an incidence of 8.6% of this complication in a case series comprising 42 patients.3 As classically described, the auriculotemporal nerve block is performed with 5 mL of local anesthetic injected 1.5 cm anterior to the ear at the level of the tragus, being careful to identify the superficial temporal artery (and performing negative aspiration) before injection. The proximity of the facial nerve to the site of injection, however, (Fig. 1) and the subsequent distribution of the local anesthetic with this technique may lead to temporary facial nerve palsy, which may confuse the diagnosis of postsurgical facial nerve palsy. To avoid this potential complication, we have had good experience with and recommend an alternate technique for blocking the auriculotemporal nerve when performing selective scalp nerve block. We suggest blocking this nerve 1 cm above the level of the tragus (farther away from the facial nerve), just behind the superficial temporal artery (again with negative aspiration first, or alternatively with Doppler ultrasound to identify the course of the artery when it is difficult to palpate), and decreasing the amount of local anesthetic administered to 3 mL (to diminish local anesthetic spread). Strict attention to perpendicular injection (not obliquely) should be maintained. Both the superficial temporal artery and the auriculotemporal nerve branch anteriorly and posteriorly at the level of www.jnsa.com |
271
Correspondence
J Neurosurg Anesthesiol
Volume 26, Number 3, July 2014
the top of the ear, so the block should not be performed above this branching point where the block may be less effective. Care must be taken to avoid the posterior branch of the artery.
John F. Bebawy, MD* Federico Bilotta, MD, PhDw Antoun Koht, MD* *Department of Anesthesiology and Neurological Surgery, Northwestern University Feinberg School of Medicine Chicago, IL wDepartment of Anesthesiology, Critical Care, and Pain Medicine, Section of Neurocritical Care, “Sapienza” University of Rome, Italy
REFERENCES
FIGURE 1. Cadaveric dissection demonstrating the “traditional” (lower arrow) and “modified” (upper arrow) location for placement of the auriculotemporal nerve block. Note the bifurcations of both the superficial temporal artery and the auriculotemporal nerve at the level of the top of the ear (with permission from James P. Chandler, MD, Northwestern University). Adaptations are themselves works protected by copyright. So in order to publish this adaptation, authorization must be obtained both from the owner of the copyright in the original work and from the owner of copyright in the translation or adaptation.
272 | www.jnsa.com
1. Bala I, Gupta B, Bhardwaj N, et al. Effect of scalp block on postoperative pain relief in craniotomy patients. Anaesth Intensive Care. 2006;34:224–227. 2. Pinosky ML, Fishman RL, Reeves ST, et al. The effect of bupivacaine skull block on the hemodynamic response to craniotomy. Anesth Analg. 1996;83:1256–1261. 3. McNicholas EJ, Bilotta F, Titi L, et al. Transient facial nerve palsy after auriculotemporal nerve block in awake craniotomy patients. Anesth Analg Case Rep. 2013. (In press). DOI: 10.1097/ACC.0b013e3182a 8ee71.
r
2014 Lippincott Williams & Wilkins
2.
3. 4.
5.
6.
Volume 26, Number 3, July 2014
blood pressure determinations. J Neurosurg Anesthesiol. 2013;25:154–161. Schonberger RB, Burg MM, Holt NF, et al. The relationship between day-of-surgery and primary care blood pressure among Veterans presenting from home for surgery. Is there evidence for anesthesiologist-initiated blood pressure referral? Anesth Analg. 2012; 114:205–214. McKesson E. The reaction of certain circulatory conditions to anesthesia and surgery. Anesth Analg. 1923;43–49. Schonberger RB, Barash PG. Impact versus impact factor: revisiting a classic article that was never cited. Anesth Analg. 2012;115: 1286–1287. Park S-J, Park JB, Choi D-J, et al. Detection of masked hypertension and the ‘mask effect’ in patients with well-controlled office blood pressure. Circ J. 2011;75:357–365. Frieden TR, Berwick DM. The “Million Hearts” initiative—preventing heart attacks and strokes. N Engl J Med. 2011;365:e27.
Can Preoperative Betaxolol Eye Drops Reduce the Incidence of Postoperative Visual Loss (POVL)?
blinded to the results, and the person collecting the IOP measurements was blinded to which eye had received the medication. Results were unblinded at the conclusion of the study. Our modest sample size yielded an average increase in IOP of 117% in the control group compared with 93% in the betaxolol group. The mean prone duration was 5.5 hours. Although the overall results were not statistically significant, we did encounter one study patient who seemed to have a more profound effect. A middle-aged patient underwent complex spine surgery and was lying prone for 11 hours. Blood loss was 3500 mL, and he received a total of 7 L of crystalloid, 2 L of colloid, and 2 units of packed cells. The saline control eye saw an increase in IOP from 7 to 43, whereas the betaxololtreated eye went from 10 to 20. We bring this case to the reader’s attention as it suggests a possible protective effect of betaxolol administration preoperatively for prevention of IOP increase in patients at risk for POVL.
Karl Zheng, MD John G. Brock-Utne, MD, PhD
To the Editor: Recently, we completed a study on a patient in a clinical study entitled: Does the use of Betaxolol prevent the potential increase in intraocular pressure in anesthetized patients in the prone position? We believe that this one case, in particular, in our study group of 10 patients illustrates the potential benefit of betaxolol in the possible prevention of postoperative visual loss (POVL). In our study, betaxolol (0.5%) eye drops were administered in the preoperative holding area to one eye randomly, with the other eye receiving a saline drop. We then used a Reichert Tono-Pen XL (Buffalo, NY) to measure intraocular pressure (IOP) in both the eyes at the beginning of the case following intubation and at the end of the case before extubation. The person administering the eye drops was
To JNA Readers: Selective scalp nerve block is a technique which has been increasingly
The authors have no funding or conflicts of interest to disclose.
The authors have no funding or conflicts of interest to disclose.
r
2014 Lippincott Williams & Wilkins
Department of Anesthesiology Perioperative and Pain Medicine Stanford University School of Medicine Stanford CA
A Modified Technique for Auriculotemporal Nerve Blockade When Performing Selective Scalp Nerve Block for Craniotomy
Correspondence
used as a surgical anesthetic before awake craniotomy and to decrease analgesic requirements after craniotomy performed under general anesthesia.1 As described by Pinosky et al in 1996,2 6 nerves (4 branches of the trigeminal nerve and the anterior and posterior rami of C2) are identified by landmarks on each side of the cranium (supratrochlear, supraorbital, zygomaticotemporal, auriculotemporal, lesser occipital, and greater occipital nerves) and subsequently infiltrated with volumes of local anesthetic ranging from 2 to 5 mL. A seemingly rare complication of auriculotemporal nerve blockade is inadvertent blockade of the adjacent facial nerve. However, 2 of the authors recently reported an incidence of 8.6% of this complication in a case series comprising 42 patients.3 As classically described, the auriculotemporal nerve block is performed with 5 mL of local anesthetic injected 1.5 cm anterior to the ear at the level of the tragus, being careful to identify the superficial temporal artery (and performing negative aspiration) before injection. The proximity of the facial nerve to the site of injection, however, (Fig. 1) and the subsequent distribution of the local anesthetic with this technique may lead to temporary facial nerve palsy, which may confuse the diagnosis of postsurgical facial nerve palsy. To avoid this potential complication, we have had good experience with and recommend an alternate technique for blocking the auriculotemporal nerve when performing selective scalp nerve block. We suggest blocking this nerve 1 cm above the level of the tragus (farther away from the facial nerve), just behind the superficial temporal artery (again with negative aspiration first, or alternatively with Doppler ultrasound to identify the course of the artery when it is difficult to palpate), and decreasing the amount of local anesthetic administered to 3 mL (to diminish local anesthetic spread). Strict attention to perpendicular injection (not obliquely) should be maintained. Both the superficial temporal artery and the auriculotemporal nerve branch anteriorly and posteriorly at the level of www.jnsa.com |
271
Correspondence
J Neurosurg Anesthesiol
Volume 26, Number 3, July 2014
the top of the ear, so the block should not be performed above this branching point where the block may be less effective. Care must be taken to avoid the posterior branch of the artery.
John F. Bebawy, MD* Federico Bilotta, MD, PhDw Antoun Koht, MD* *Department of Anesthesiology and Neurological Surgery, Northwestern University Feinberg School of Medicine Chicago, IL wDepartment of Anesthesiology, Critical Care, and Pain Medicine, Section of Neurocritical Care, “Sapienza” University of Rome, Italy
REFERENCES
FIGURE 1. Cadaveric dissection demonstrating the “traditional” (lower arrow) and “modified” (upper arrow) location for placement of the auriculotemporal nerve block. Note the bifurcations of both the superficial temporal artery and the auriculotemporal nerve at the level of the top of the ear (with permission from James P. Chandler, MD, Northwestern University). Adaptations are themselves works protected by copyright. So in order to publish this adaptation, authorization must be obtained both from the owner of the copyright in the original work and from the owner of copyright in the translation or adaptation.
272 | www.jnsa.com
1. Bala I, Gupta B, Bhardwaj N, et al. Effect of scalp block on postoperative pain relief in craniotomy patients. Anaesth Intensive Care. 2006;34:224–227. 2. Pinosky ML, Fishman RL, Reeves ST, et al. The effect of bupivacaine skull block on the hemodynamic response to craniotomy. Anesth Analg. 1996;83:1256–1261. 3. McNicholas EJ, Bilotta F, Titi L, et al. Transient facial nerve palsy after auriculotemporal nerve block in awake craniotomy patients. Anesth Analg Case Rep. 2013. (In press). DOI: 10.1097/ACC.0b013e3182a 8ee71.
r
2014 Lippincott Williams & Wilkins
