TY - JOUR

T1 - The intertransverse process block single- or multiple-injection? A study protocol

AU - de la Fuente Birkebæk, Amanda

AU - Tanggaard, Katrine

AU - Bojesen, Sophie

AU - Therkelsen, Anne Sofie

AU - Klementsen, Cecilie H.

AU - Hansen, Christian K.

AU - Vazin, Mojgan

AU - Poulsen, Troels Dirch

AU - Børglum, Jens

AU - Nielsen, Martin V.

N1 - Funding Information: Martin V. Nielsen has received donations from Region Zealand Health Science Foundation and Lægefonden, A. P. Møller Mærsk. The authors declare no conflicts of interest. Publisher Copyright: © 2023 The Authors. Acta Anaesthesiologica Scandinavica published by John Wiley & Sons Ltd on behalf of Acta Anaesthesiologica Scandinavica Foundation.

PY - 2023/8

Y1 - 2023/8

N2 - Background and Aims: Intertransverse process (ITP) blocks are applied on the posterior side of the thoracic paravertebral space. The modality is described as being a paravertebral block by proxy, possibly providing a similar analgesic effect as the thoracic paravertebral block. However, systematic evidence on anaesthetised dermatomes and the extent of cutaneous sensory loss following ITP blocks is sparse. This study aims to test the single- versus the multiple-injection ITP block. The primary outcome is the number of anaesthetised thoracic dermatomes for each block type. Methods: Twelve healthy male volunteers will participate in this randomised, procedure-related, double-blinded, non-inferiority crossover trial after informed consent. Blinded participants will receive either a unilateral single-injection ITP block with 21 mL ropivacaine 7.5 mg/mL including two sham blocks or a unilateral multiple-injection ITP block with 3 × 7 mL ropivacaine 7.5 mg/mL on study Day 1, and the other modality on study Day 2. Block applicants will be blinded from outcome assessment and vice versa. Following block application sensory test by mechanical pinprick and temperature discrimination will be performed. Anterior truncal thermography will be measured three times after block application to compare skin temperature in the mid-clavicular line between the blocked and the contralateral non-blocked hemithorax. In addition, blood pressure changes are measured three times non-invasively. Discussion: The current study will provide substantial knowledge regarding the cutaneous sensory loss of the ITP block. Furthermore, the study might provide insight regarding the possible clinical usage of thermography as a reliable instrument for measuring nerve block efficacy.

AB - Background and Aims: Intertransverse process (ITP) blocks are applied on the posterior side of the thoracic paravertebral space. The modality is described as being a paravertebral block by proxy, possibly providing a similar analgesic effect as the thoracic paravertebral block. However, systematic evidence on anaesthetised dermatomes and the extent of cutaneous sensory loss following ITP blocks is sparse. This study aims to test the single- versus the multiple-injection ITP block. The primary outcome is the number of anaesthetised thoracic dermatomes for each block type. Methods: Twelve healthy male volunteers will participate in this randomised, procedure-related, double-blinded, non-inferiority crossover trial after informed consent. Blinded participants will receive either a unilateral single-injection ITP block with 21 mL ropivacaine 7.5 mg/mL including two sham blocks or a unilateral multiple-injection ITP block with 3 × 7 mL ropivacaine 7.5 mg/mL on study Day 1, and the other modality on study Day 2. Block applicants will be blinded from outcome assessment and vice versa. Following block application sensory test by mechanical pinprick and temperature discrimination will be performed. Anterior truncal thermography will be measured three times after block application to compare skin temperature in the mid-clavicular line between the blocked and the contralateral non-blocked hemithorax. In addition, blood pressure changes are measured three times non-invasively. Discussion: The current study will provide substantial knowledge regarding the cutaneous sensory loss of the ITP block. Furthermore, the study might provide insight regarding the possible clinical usage of thermography as a reliable instrument for measuring nerve block efficacy.

KW - intertransverse process block

KW - peripheral nerve block

KW - single- versus multiple-injection

U2 - 10.1111/aas.14248

DO - 10.1111/aas.14248

M3 - Journal article

C2 - 37118985

AN - SCOPUS:85158066695

VL - 67

SP - 987

EP - 992

JO - Acta Anaesthesiologica Scandinavica

JF - Acta Anaesthesiologica Scandinavica

SN - 0001-5172

IS - 7

ER -