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Research Article
Kamen Vlassakov
Department of Anesthesiology, Perioperative and Pain Medicine, Brigham and Women’s Hospital, Harvard Medical School
Corresponding Author
ORCiD: https://orcid.org/0000-0002-7704-3709
License:
This work is licensed under a CC BY 4.0 License. Read Full License
Background: The ultrasound-guided proximal intercostal block (PICB) is performed at the proximal intercostal space (ICS) between the internal intercostal membrane (IIM) and the endothoracic fascia/parietal pleura (EFPP) complex. Injectate spread may follow several routes and allow for multilevel trunk analgesia. The goal of this study was to examine the anatomical spread of large-volume PICB injections and its relevance to breast surgery analgesia.
Methods: Fifteen two-level PICBs were performed in ten soft-embalmed cadavers. Radiographic contrast mixed with methylene blue was injected at the 2nd(15ml) and 4th(25ml) ICS, respectively. Fluoroscopy and dissection were performed to examine the injectate spread. Additionally, the medical records of 12 patients who had PICB for breast surgery were reviewed for documented dermatomal levels of clinical hypoesthesia. The records of twelve matched patients who had the same operations without PICB were reviewed to compare analgesia and opioid consumption.
Results: Median contrast/dye spread was 4(2-8) and 3(2-5) vertebral segments by fluoroscopy and dissection respectively. Dissection revealed injectate spread to the adjacent paravertebral space, T3 (60%) and T5 (27%), and cranio-caudal spread along the endothoracic fascia (80%). Clinically, the median documented area of hypoesthesia was 5(4-7) dermatomes with 100% and 92% of the injections covering adjacent T3 and T5 dermatomes, respectively. The patients with PICB had significantly lower perioperative opioid consumption and trend towards lower pain scores.
Conclusions: In this anatomical study, PICB at the 2nd and 4th ICS produced lateral spread along the corresponding intercostal space, medial spread to the adjacent paravertebral/epidural space and cranio-caudal spread along the endothoracic fascial plane. Clinically, combined PICBs at the same levels resulted in consistent segmental chest wall analgesia and reduction in perioperative opioid consumption after breast surgery. The incomplete overlap between paravertebral spread in the anatomical study and area of hypoesthesia in our clinical findings, suggests that additional non-paravertebral routes of injectate distribution, such as the endothoracic fascial plane, may play important clinical role in the multi-level coverage provided by this block technique.
Keywords: Nerve block, paravertebral space, intercostal space, intercostal block, breast surgery.
Keywords
Nerve block, paravertebral space, intercostal space, intercostal block, breast surgery
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CURRENT STATUS: Published
View the published article at BMC Anesthesiology.
No community comments so far
Editorial decision: Accept
On 19 May, 2019
Submission checks complete
On 17 May, 2019
Editor invited
On 17 May, 2019
Editor assigned
On 17 May, 2019
No comments provided
Editorial decision: Minor revision
On 14 May, 2019
Review #2 received
Received 13 May, 2019
Review #1 received
Received 10 May, 2019
Reviewer #2 agreed
On 10 May, 2019
Reviewer #1 agreed
On 27 Apr, 2019
Reviewers invited
Invitations sent on 14 Apr, 2019
Editor invited
On 11 Apr, 2019
Editor assigned
On 11 Apr, 2019
Submission checks complete
On 06 Feb, 2019
Version 1
Posted 11 Feb, 2019
No comments provided
Editorial decision: Major revision
On 11 Mar, 2019
Review #1 received
Received 24 Feb, 2019
Review #2 received
Received 19 Feb, 2019
Reviewer #2 agreed
On 12 Feb, 2019
Reviewer #3 agreed
On 12 Feb, 2019
Reviewer #1 agreed
On 10 Feb, 2019
Editor assigned
On 07 Feb, 2019
Reviewers invited
Invitations sent on 07 Feb, 2019
Submission checks complete
On 06 Feb, 2019
Editor invited
On 06 Feb, 2019
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A new preprint design is coming!
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See the published version of this preprint at BMC Anesthesiology.
This is a preprint, a preliminary version of a manuscript that has not completed peer review at a journal. Research Square does not conduct peer review prior to posting preprints. The posting of a preprint on this server should not be interpreted as an endorsement of its validity or suitability for dissemination as established information or for guiding clinical practice.
Learn more about In Review
Research Article
Kamen Vlassakov
Department of Anesthesiology, Perioperative and Pain Medicine, Brigham and Women’s Hospital, Harvard Medical School
Corresponding Author
ORCiD: https://orcid.org/0000-0002-7704-3709
Badges
Prescreen
This manuscript passed our Prescreen assessment
Complete author information
Appropriate declaration statements
Potential risks to human health
Prescreen
Peer Review Timeline
CURRENT STATUS: Published
View the published article at BMC Anesthesiology.
No community comments so far
Editorial decision: Accept
On 19 May, 2019
Submission checks complete
On 17 May, 2019
Editor invited
On 17 May, 2019
Editor assigned
On 17 May, 2019
No comments provided
Editorial decision: Minor revision
On 14 May, 2019
Review #2 received
Received 13 May, 2019
Review #1 received
Received 10 May, 2019
Reviewer #2 agreed
On 10 May, 2019
Reviewer #1 agreed
On 27 Apr, 2019
Reviewers invited
Invitations sent on 14 Apr, 2019
Editor invited
On 11 Apr, 2019
Editor assigned
On 11 Apr, 2019
Submission checks complete
On 06 Feb, 2019
Version 1
Posted 11 Feb, 2019
No comments provided
Editorial decision: Major revision
On 11 Mar, 2019
Review #1 received
Received 24 Feb, 2019
Review #2 received
Received 19 Feb, 2019
Reviewer #2 agreed
On 12 Feb, 2019
Reviewer #3 agreed
On 12 Feb, 2019
Reviewer #1 agreed
On 10 Feb, 2019
Editor assigned
On 07 Feb, 2019
Reviewers invited
Invitations sent on 07 Feb, 2019
Submission checks complete
On 06 Feb, 2019
Editor invited
On 06 Feb, 2019
Metrics
Comments: 0
PDF Downloads: ...
HTML Views: ...
Subject Areas
Internal Medicine Specialties
License:
This work is licensed under a CC BY 4.0 License. Read Full License
View the published article at BMC Anesthesiology.
Background: The ultrasound-guided proximal intercostal block (PICB) is performed at the proximal intercostal space (ICS) between the internal intercostal membrane (IIM) and the endothoracic fascia/parietal pleura (EFPP) complex. Injectate spread may follow several routes and allow for multilevel trunk analgesia. The goal of this study was to examine the anatomical spread of large-volume PICB injections and its relevance to breast surgery analgesia.
Methods: Fifteen two-level PICBs were performed in ten soft-embalmed cadavers. Radiographic contrast mixed with methylene blue was injected at the 2nd(15ml) and 4th(25ml) ICS, respectively. Fluoroscopy and dissection were performed to examine the injectate spread. Additionally, the medical records of 12 patients who had PICB for breast surgery were reviewed for documented dermatomal levels of clinical hypoesthesia. The records of twelve matched patients who had the same operations without PICB were reviewed to compare analgesia and opioid consumption.
Results: Median contrast/dye spread was 4(2-8) and 3(2-5) vertebral segments by fluoroscopy and dissection respectively. Dissection revealed injectate spread to the adjacent paravertebral space, T3 (60%) and T5 (27%), and cranio-caudal spread along the endothoracic fascia (80%). Clinically, the median documented area of hypoesthesia was 5(4-7) dermatomes with 100% and 92% of the injections covering adjacent T3 and T5 dermatomes, respectively. The patients with PICB had significantly lower perioperative opioid consumption and trend towards lower pain scores.
Conclusions: In this anatomical study, PICB at the 2nd and 4th ICS produced lateral spread along the corresponding intercostal space, medial spread to the adjacent paravertebral/epidural space and cranio-caudal spread along the endothoracic fascial plane. Clinically, combined PICBs at the same levels resulted in consistent segmental chest wall analgesia and reduction in perioperative opioid consumption after breast surgery. The incomplete overlap between paravertebral spread in the anatomical study and area of hypoesthesia in our clinical findings, suggests that additional non-paravertebral routes of injectate distribution, such as the endothoracic fascial plane, may play important clinical role in the multi-level coverage provided by this block technique.
Keywords: Nerve block, paravertebral space, intercostal space, intercostal block, breast surgery.
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