Epidural insertion simulator of higher insertion resistance & drop rate after puncture

Abstract

Accidents such as dural puncture remain one of the problems of epidural anesthesia, and unskilled doctors can repeat such accidents. The purpose of the current research was to provide a new simulator for epidural insertion training. No reference data regarding the resistance force used when inserting a needle into patients have been reported. A comparative study was conducted to aid in the development of a new simulator. Pork loin (n=5) were employed as a substitute for patients. Thickness was set at 2 cm so as to improve the reproducibility. The authors took the conventional simulator apart, and picked a block as an analogue of muscle and ligamentum flavum. A new simulator was made of a melamine foam resin block and a latex rubber sheet. An epidural needle fixed on a motorized stage was inserted at the speed of 2 mm per second. The reaction force was measured while the needle was inserted into each specimen. Waveform of the pork loin exhibited two slopes of different inclines up to peaks and then falls after puncture. The conventional simulator showed a simple increase up to peak and a slow fall after puncture. In contrast, the new simulator showed two slopes up to peak and then a sudden fall after puncture. The insertion resistances were 2.5 N/s for the porcine, 0.8 N/s for the conventional and 2.1 N/s for the new simulator. The drop rates were 5 N/s for the porcine, 0.6 N/s for the conventional and 24 N/s for the new simulator. The higher insertion resistance and drop rate for the new simulator than the conventional simulator will be suitable for epidural insertion training.

Objective Evaluation of a New Epidural Simulator by the CompuFlo®Epidural Instrument

“…Naemura et al [ 10 ] studied the force of penetration waveforms of the epidural needle into a porcine model, reporting two peaks representing the needle penetrating in the supraspinous ligament and/or the muscle fiber and in the ligamentum flavum. Conventional simulators have been reported to be able to show only the simple increase up to peak when the needle is in the ligamentum flavum, followed by a plateau when the needle reaches the epidural space.…”

Force Modeling, Identification, and Feedback Control of Robot-Assisted Needle Insertion: A Survey of the Literature

“…Meanwhile, piezomagnetic materials remain to be developed for force sensing during needle insertion [ 3 ]. Some control algorithms such as neural networks, general bilateral control and the modified extended Kalman filter are used to reduce the measurement bias and noise [ 3 , 101 , 108 , 109 , 110 , 111 , 135 ].…”

“…The image-based method is suitable for experiments equipped with imaging devices, which could reduce the cost and uncertainty of additional sensors [ 3 , 71 , 134 , 135 ]. They acquired the force information according to the image features such as the computed tomography (CT) value [ 62 ].…”

“…The porcine and bovine tissues or organs are most commonly used in insertion experiments [ 25 , 27 , 28 , 42 , 44 , 69 , 74 , 75 , 76 , 119 , 122 , 126 , 127 , 128 , 129 , 130 ]. Meanwhile, many scholars presented artificial phantoms to replace the use of animal organs considering reproducibility, visibility, ethics and morals [ 22 , 46 , 82 , 122 , 133 , 134 , 135 , 136 , 137 ]. Although manmade materials have many advantages, we must make a reasonable selection in accordance with practical considerations owing to the differences between artificial materials and practical organs.…”

An efficient capacitive sensing scheme for an ophthalmic regional anesthesia training system

“…The capacitive array sensing based training manikin proposed in [8] lacks the underlying anatomical features of the eye and orbit necessary for accurate representation of the training environment. Haptic based simulators [9], [10] require complex finite element tissue deformation models, making them computationally burdensome and slow. Also, optical tracking systems used in [9] require direct line of sight between the imaging system and the needle, thus, restricting the movement of the trainee, who fails to perceive a true training environment.…”