Predictors of Unilateral Spinal Block Success (UNISS)
Determination of Factors Affecting Success in Unilateral Spinal Anesthesia: A Prospective Observational Study
This prospective observational study aims to determine the factors affecting the success of unilateral spinal anesthesia in patients undergoing orthopedic lower extremity surgery. Unilateral spinal anesthesia is preferred to minimize unwanted effects such as hypotension and to provide more stable hemodynamic conditions, especially in vulnerable patient populations.
Unilateral spinal anesthesia is defined as achieving sensory and motor block predominantly on the operated side without significant contralateral spread. However, the factors influencing the success of this technique have not been fully clarified.
This study will evaluate various patient-related and procedure-related factors, including age, sex, body mass index, patient positioning, needle type and orientation, injection technique and local anesthetic dose. The primary outcome is the success of unilateral spinal anesthesia, defined as the absence of contralateral block.
The results of this study are expected to contribute to improving clinical practice by identifying major and minor factors affecting block success and optimizing anesthesia techniques.
Visão geral do estudo
Status
Descrição detalhada
This prospective observational study is designed to investigate the factors influencing the success of unilateral spinal anesthesia in patients undergoing lower extremity orthopedic surgery.
Spinal anesthesia is widely used in lower extremity procedures; however, it may be associated with hemodynamic instability such as hypotension. Unilateral spinal anesthesia has been proposed as a technique to limit sympathetic blockade and maintain more stable hemodynamic conditions. Despite its advantages, the determinants of successful unilateral block remain unclear.
Patients aged between 18 and 65 years with American Society of Anesthesiologists (ASA) physical status I-III who are scheduled for elective lower extremity surgery will be included in the study after providing written informed consent. This study will be conducted in a single tertiary care center.
No intervention will be performed by the investigator. All anesthesia procedures will be carried out according to routine clinical practice. The investigator will record patient demographics, including age, sex, height, weight, and body mass index.
Procedure-related variables such as patient positioning, spinal needle type, needle orientation, injection speed, level of injection, local anesthetic type and dose will be recorded.
Block characteristics will be assessed intraoperatively, including sensory and motor block distribution. The primary outcome is defined as successful unilateral spinal anesthesia, characterized by the absence of contralateral sensory block. Secondary outcomes include factors associated with block success and variability in block characteristics.
Data will be collected using standardized case report forms and analyzed to identify factors influencing the success of unilateral spinal anesthesia. The results of this study are expected to contribute to optimizing anesthesia techniques and improving patient safety.
Tipo de estudo
Inscrição (Real)
Contactos e Locais
Locais de estudo
-
-
-
Izmir, Turquia (Türkiye)
- İzmir City Hospital
-
-
Critérios de participação
Critérios de elegibilidade
Idades elegíveis para estudo
- Adulto
- Adulto mais velho
Aceita Voluntários Saudáveis
Método de amostragem
População do estudo
Descrição
Inclusion Criteria:
- Patients aged 18-65 years
- ASA physical status I-III
- Undergoing elective unilateral lower extremity surgery under spinal anesthesia
- Provided written informed consent
Exclusion Criteria:
- ASA IV patients
- Known allergy to local anesthetics
- Contraindications to spinal anesthesia
- Decompensated congestive heart failure
- Hemodynamic instability (including sepsis, septic shock, or need for inotropic support)
- Pregnancy
- Patients with vertebral anomalies (e.g., scoliosis, vertebral fractures) preventing proper positioning
Plano de estudo
Como o estudo é projetado?
Detalhes do projeto
Coortes e Intervenções
Grupo / Coorte |
|---|
|
patients undergoing unilateral spinal anesthesia
Patients aged 18-65 years with ASA physical status I-III undergoing elective unilateral lower extremity surgery under spinal anesthesia.
|
O que o estudo está medindo?
Medidas de resultados primários
Medida de resultado |
Descrição da medida |
Prazo |
|---|---|---|
|
Unilateral Spinal Block Success Rate
Prazo: Intraoperative period (within first 30 minutes after spinal anesthesia
|
Successful unilateral spinal anesthesia defined as the absence of contralateral sensory block, assessed by pinprick test and bromage scale within the first 20 minutes after spinal anesthesia.
|
Intraoperative period (within first 30 minutes after spinal anesthesia
|
Medidas de resultados secundários
Medida de resultado |
Descrição da medida |
Prazo |
|---|---|---|
|
Rate of unilateral spinal anesthesia success by age
Prazo: Intraoperative period
|
Proportion (%) of patients achieving unilateral spinal anesthesia success across age groups.
|
Intraoperative period
|
|
Rate of unilateral spinal anesthesia success by BMI
Prazo: Intraoperative period
|
Proportion (%) of patients achieving unilateral spinal anesthesia success across age groups.
|
Intraoperative period
|
|
Rate of unilateral spinal anesthesia success by position
Prazo: Intraoperative period
|
Proportion (%) of unilateral spinal anesthesia success by patient positioning during injection (lateral vs sitting).
|
Intraoperative period
|
|
Rate of unilateral spinal anesthesia success by needle type
Prazo: Intraoperative period
|
Proportion (%) of unilateral spinal anesthesia success by spinal needle type (Quincke vs pencil-point).
|
Intraoperative period
|
|
Rate of unilateral spinal anesthesia success by needle gauge
Prazo: Intraoperative period
|
Proportion (%) of unilateral spinal anesthesia success by needle gauge.
|
Intraoperative period
|
|
Rate of unilateral spinal anesthesia success by local aneshtetic dose
Prazo: Intraoperative period
|
Proportion (%) of unilateral spinal anesthesia success by administered local anesthetic dose (mg).
|
Intraoperative period
|
|
Rate of unilateral spinal anesthesia success by injection speed
Prazo: Intraoperative period
|
Proportion (%) of unilateral spinal anesthesia success by injection speed category (faster vs ≤1 mL/5 s).
|
Intraoperative period
|
|
Sensory Block Level and Distribution
Prazo: Intraoperative period
|
Assessment of sensory block level (dermatomal level) and comparison between operated and non-operated sides.
|
Intraoperative period
|
|
Rate of unilateral spinal anesthesia success by intervertebral level of spinal injection
Prazo: Intraoperative period
|
Proportion (%) of unilateral spinal anesthesia success by intervertebral level (L1-2,L2-3,L3-L4 ,L4-L5).
|
Intraoperative period
|
Colaboradores e Investigadores
Patrocinador
Investigadores
- Investigador principal: Derya Arslan Yurtlu, MD, İzmir City Hospital
Datas de registro do estudo
Datas Principais do Estudo
Início do estudo (Real)
Conclusão Primária (Real)
Conclusão do estudo (Real)
Datas de inscrição no estudo
Enviado pela primeira vez
Enviado pela primeira vez que atendeu aos critérios de CQ
Primeira postagem (Real)
Atualizações de registro de estudo
Última Atualização Postada (Real)
Última atualização enviada que atendeu aos critérios de controle de qualidade
Última verificação
Mais Informações
Termos relacionados a este estudo
Palavras-chave
Outros números de identificação do estudo
- UNISS-2025
Plano para dados de participantes individuais (IPD)
Planeja compartilhar dados de participantes individuais (IPD)?
Descrição do plano IPD
Essas informações foram obtidas diretamente do site clinicaltrials.gov sem nenhuma alteração. Se você tiver alguma solicitação para alterar, remover ou atualizar os detalhes do seu estudo, entre em contato com register@clinicaltrials.gov. Assim que uma alteração for implementada em clinicaltrials.gov, ela também será atualizada automaticamente em nosso site .