Scalp block and New GCS (GCS-P)

Scalp block is simple and easy to perform. It has the advantages of minimizing cardiovascular effects and decreasing intraoperative analgesia requirements.
New GCS, the GCS-P was adopted in 2018 by the same person who proposed GCS. It gives better prognosticate outcomes compared to GCS.

1. SCALP block GCS - P Tenzin Yoezer 1/6/2019

2. Scalp block

3. Scalp block Local anesthesia of the nerves of the scalp Sensory innervation of the scalp and forehead is provided by both the trigeminal and spinal nerves Girvin originally described the ‘‘scalp block’’ technique in 1986 for use during awake craniotomy, the technique did not gain its due popularity for several more years

4. Scalp block It was not until the middle of 1980s that Hillman et al performed the first double-blind randomized study to compare the effects of 0.5% bupivacaine with normal saline injection in patients undergoing craniotomies . I ncreased cardiovascular hemodynamic stability was found in the bupivacaine group.

5. Scalp block Four years later, Hartley et al demonstrated similar results in children undergoing supratentorial craniotomy. In this study, responses of mean arterial pressure and heart rate to scalp incision and reflection were attenuated by infiltrating the scalp subcutaneously along the proposed incision line with bupivacaine coupled with epinephrine

6. Scalp block Bupivacaine became the local anesthetic of choice for scalp infiltration due to its long duration of action and was reported to be safe when used in the vascular tissues of the scalp

7. A dvantages local anesthetic infiltration of the scalp before craniotomy is effective in reducing tachycardia and hypertension – decrease CBF and intracranial pressure prevent the need for increased analgesic requirements early in the surgical procedure

8. Technical description 6 nerves are blocked : Supraorbital Supratrochlear nerve Auriculotemporal nerve Zygomaticotemporal nerve Greater occipital nerve Lessor occipital nerve

9. T echniques Supraorbital Nerve Palpation of Supraorbital notch Needle – 1 cm medial to supraorbital foramen perpendicular to skin Supratrochlear nerve Medial extension of supraorbital block above eyebrow line Auriculotemporal Nerve over zygomatic process, with 1 to 1.5 cm anterior to the ear at the level of the tragus Palpate superficial temporal artery

10. Zygomaticotemporal Nerve infiltration from the supraorbital margin to the posterior part of the zygomatic arch. Need deep and superficial block Greater Occipital Nerve approximately halfway between the occipital protuberance and the mastoid process, 2.5cm lateral to the nuchal median line Best landmark – palpate the occipital artery, and inject medially after careful aspiration Lessor occipital nerve Infiltration along the superior nucheal line, 2.5 cm lateral to the greater occipital nerve

11. Scalp block Indication: Surgery In the scalp area Awake craniotomy Before putting pins Post craniotomy analgesia Drugs: 0.25%, 0.5% bupivacaine, 2% lidocaine With 1:200,000epinephrine (2ml, 5ml, 2ml, 5ml)

12. Complications Hypertension due to intravascular injection or systemic absorption of bupivacaine mixed with vasoconstrictor Rapid rise in anesthetic concentration within first 15 minutes Hypotensive episodes Subarachnoid injection during occipital block Facial nerve paralysis infection

13. New gcs = gcs -p

14. New Gcs GCS developed by prof. grham teasdale in 1974 Designed to quantify the level of consciousness in TBI patients Initial point is only 14

15. In 2014 ( 40 yrs , on its aniniversary )- terminology was updated to simplify the language used Glasgow Coma Scale 2014

16. Another changes in 2014 is no points for non-testable component. Eg : 42 year old man, intubated after traumatic brain injury (TBI) for decreasing GCS. Currently, he opens his eyes to pressure, is intubated, and withdraws his left arm and leg to pain.  1979  – GCS: E 2, V 1t, M 4. Combined GCS: 7t 2014  – GCS: E 2, V NT, M 4 . = 6NT Any element that cannot be tested should be marked as NT, for “not testable” 4 .

17. 2018 Adoption of pupil reactivity score ( GCS- P) Improves to prognosticate based on initial presentation Helps to downstream the management Helps to guide goals of care discussion.

18. Subtracted from the GCS GCS-P is adopted from the pooled CRASH and IMPACT trail GCS 6 – 6 month mortality 28.82% GCS-P (6-2=4) – 6 month mortality of 42.94% Therefore, addition of a pupil examination appears to allow clinicians to prognosticate outcomes better than GCS alone and can be done quickly and easily at the bedside .

19. R eferences calp Block’’ During Craniotomy: A Classic Technique Revisited, Irene Osborn, MD and Joseph Sebeo , PhD https://emottawablog.com/2018/07/gcs-remastered-recent-updates-to-the-glasgow-coma-scale-gcs-p / https:// www.eurekalert.org / pub_releases /2018-04/jonp-ngc040418.php

20. Thank you