Ultrasound Prescan vs Conventional Landmark-guided Technique in Spinal Anesthesia in Orthopedic Obese Patients

Istituto Ortopedico Rizzoli

Status: Completed

Conditions: Ultrasonography; Anesthesia, Spinal; Obesity; Body Mass Index

Treatments: Procedure: cutaneous landmarks; Device: Accuro

Study type: Interventional

Funder types: Other

Identifiers

NCT03075488

IOR-ACCURO

Details and patient eligibility

About

The study is aimed at evaluating whether ultrasound pre-procedural scan with Accuro may reduce needle redirections when performing spinal injection in patients with BMI = or > 30 in orthopedic surgery

Full description

This is a open-label randomised controlled study.

90 patients will be recruited and divided into two groups of 45 patients per group.

Patient recruitment will be performed by patient visit and checking inclusions and exclusion criteria. After written informed consent, every single patient will be allocated in one of the two groups following a computer generated randomization list.

Patients in both groups will undergo:

• standard monitoring with Non Invasive Blood Pressure (NIBP) cuff, three-lead electrocardiography (ECG) and Pulse-oximetry (SpO2).
• Peripheral intravenous access
• Sedation (as prescribed by the OR anesthesiologist)
• Spinal anesthesia performed by anesthesiologists skilled in both techniques (conventional landmark technique or Accuro guided) at the L3-L4, L4-L5 or L5-S1 level, with a 25 or 27 Gauge needle, with the surgical side declive or proclive according to the baricity of the local anesthetic used (sitting position, when needed, will be reported in the CRF)

In both groups an observer will monitor and register spinal procedure duration (starting point: anesthesiologist wearing sterile gloves, ending point: end of local anesthetic injection).

Control group (landmark technique):

The anesthesiologist will identify lumbar spinous processes with traditional landmark palpation. Once the correct interspinous level and the mid-line will be identified, the anesthesiologist will proceed with needle insertion and spinal injection.

Treatment group (ultrasound pre-procedural scan with Accuro):

By using Accuro US probe the anesthesiologist will perform a pre-procedural lumbar spine scan to detect the needle entry site. After image optimization, the Accuro probe will be aligned with the spine mid-line, as indicated by a dashed red-line on the screen. After that the interlaminar space at the desired intervertebral level will be detected, as indicated by orange overlay in the screen. The depth and the device angle used to detect the interlaminar space will be annotated. The anesthesiologist will then disengage the Accuro Locator needle guide and press gently against the skin. Then the probe will be removed and the spinal injection will be performed.

Enrollment: 130 patients

Sex: All

Ages: 18 to 75 years old

Volunteers: No Healthy Volunteers

Inclusion criteria

• Age between 18 and 75 years
• BMI ≥ 30 kg/m2
• American Society of Anesthesiologists' (ASA) classification I-III
• Orthopedic surgery to be performed under spinal anesthesia
• Able to understand and to sign informed consent

Exclusion criteria

• Local anaesthetic allergy
• Serious spine deformities
• Previous spine surgery
• Inability to express informed consent
• Contraindications to spinal anaesthesia
• Pregnancy

Trial design

Primary purpose: Other

Allocation: Randomized

Interventional model: Parallel Assignment

Masking: None (Open label)

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130 participants in 2 patient groups

Conventional landmark-guided technique

Active Comparator group

Description:

In this arm spinal anesthesia will be performed by using conventional cutaneous landmarks

Treatment:

Procedure: cutaneous landmarks

Accuro device guided technique

Experimental group

Description:

In this arm spinal anesthesia will be performed only after having detected the intralaminar space, the mid-line, the depth and the orientation for spinal needle insertion with pre-procedural scan performed with Accuro device

Treatment:

Device: Accuro