Faculty Collaboration Database

Rationale and Design for the BLOCK-SAH Study (Pterygopalatine Fossa Block as an Opioid-Sparing Treatment for Acute Headache in Aneurysmal Subarachnoid Hemorrhage): A Phase II, Multicenter, Randomized, Double-Blinded, Placebo-Controlled Clinical Trial with a Sequential Parallel Comparison Design. Neurocrit Care 2025 Feb;42(1):290-300

Date

08/14/2024

Pubmed ID

39138719

Pubmed Central ID

PMC11810580

DOI

10.1007/s12028-024-02078-z

Scopus ID

2-s2.0-85202495216 (requires institutional sign-in at Scopus site)   8 Citations

Abstract

BACKGROUND: Acute post-subarachnoid hemorrhage (SAH) headaches are common and severe. Management strategies for post-SAH headaches are limited, with heavy reliance on opioids, and pain control is overall poor. Pterygopalatine fossa (PPF) nerve blocks have shown promising results in treatment of acute headache, including our preliminary and published experience with PPF-blocks for refractory post-SAH headache during hospitalization. The BLOCK-SAH trial was designed to assess the efficacy and safety of bilateral PPF-blocks in awake patients with severe headaches from aneurysmal SAH who require opioids for pain control and are able to verbalize pain scores.

METHODS: BLOCK-SAH is a phase II, multicenter, randomized, double-blinded, placebo-controlled clinical trial using the sequential parallel comparison design (SPCD), followed by an open-label phase.

RESULTS: Across 12 sites in the United States, 195 eligible study participants will be randomized into three groups to receive bilateral active or placebo PPF-injections for 2 consecutive days with periprocedural monitoring of intracranial arterial mean flow velocities with transcranial Doppler, according to SPCD (group 1: active block followed by placebo; group 2: placebo followed by active block; group 3: placebo followed by placebo). PPF-injections will be delivered under ultrasound guidance and will comprise 5-mL injectates of 20 mg of ropivacaine plus 4 mg of dexamethasone (active PPF-block) or saline solution (placebo PPF-injection).

CONCLUSIONS: The trial has a primary efficacy end point (oral morphine equivalent/day use within 24 h after each PPF-injection), a primary safety end point (incidence of radiographic vasospasm at 48 h from first PPF-injection), and a primary tolerability end point (rate of acceptance of second PPF-injection following the first PPF-injection). BLOCK-SAH will inform the design of a phase III trial to establish the efficacy of PPF-block, accounting for different headache phenotypes.

Author List

Busl KM, Smith CR, Troxel AB, Fava M, Illenberger N, Pop R, Yang W, Frota LM, Gao H, Shan G, Hoh BL, Maciel CB, BLOCK-SAH Investigators

Authors

Sarah Endrizzi MD Associate Professor in the Anesthesiology department at Medical College of Wisconsin
Jennifer Lynn Hernandez-Meier PhD Assistant Professor in the Emergency Medicine department at Medical College of Wisconsin
Jamie Jasti in the CTSI department at Medical College of Wisconsin - CTSI

MESH terms used to index this publication - Major topics in bold

Adult
Analgesics, Opioid
Anesthetics, Local
Clinical Trials, Phase II as Topic
Double-Blind Method
Female
Headache
Humans
Male
Middle Aged
Multicenter Studies as Topic
Nerve Block
Pterygopalatine Fossa
Randomized Controlled Trials as Topic
Subarachnoid Hemorrhage