Distance from the lumbar epidural space to the skin in Korean adults

BACKGROUND: Lumbar epidural block is a common regional anesthetic/analgesic technique. The depth of the epidural space beneath the skin surface varies from patient to patient at the same vertebral level. It also varies at different levels of the spinal column in the same patient. This study was performed to evaluate the correlations between the lumbar epidural depth and physical measurements depending on the puncture site. METHODS: Data was gathered from 1,653 patients who were undergoing elective lumbar epidural blocks for anesthesia during surgical procedures. The age, gender, height and weight were obtained from the medical records. We calculated the physical parameters such as the weight/height ratio, the body mass index (BMI) and Broca's index. Pearson's correlation analysis and regression testing between the lumbar epidural depth and the physical measurements were performed. RESULTS: The epidural depths at the L2-3, L3-4, L4-5 and L5-S1 intervertebral space were 4.4 +/- 0.62, 4.6 +/- 0.69, 4.6 +/- 0.69 and 4.1 +/- 0.52 cm, respectively. A significant correlation was found between the epidural depth and the weight/height ratio and BMI. CONCLUSIONS: The weight/height ratio and BMI showed the highest correlation with the lumbar epidural depth.

Estimating lumbar epidural space depth in infants and children of Korea / 대한마취과학회지

BACKGROUND: Lumbar epidural block is now a popular technique for anesthesia and post operative analgesia. It may be helpful for prevention of complication during this procedure to know the depth from the skin to the lumbar epidural space before the procedure. This study was undertaken to evaluate the depth from the skin to the lumbar epidural space and to determine any potential relationship between a patient's data (age, weight, and height) and the measured depth in Korean children. METHODS: We investigated the electronic records of 662 Korean children who were received urologic surgeries with epidural catheterization for postoperative analgesia. The patients' gender, age, weight, height and epidural depth were recorded and analyzed with multiple linear regression test using SPSS 13.0 (SPSS Co., Ilinois, USA). RESULTS: The patient's age and weight were significantly correlated to the skin-epidural space depth in Korean children. Body weight was more significant variable than age on the epidural depth. The empirical formula derived from the results was as follow; epidural depth (mm) = 9 + 0.5 x body weight (kg) - 0.2 x age (months). CONCLUSIONS: We suggest that the depth of skin-lumbar epidural space can be estimated with the empirical formula based on body weight and age.

A Clinical Measurement of the Distance from the Skin to the High Thoracic Epidural Space in Women / 대한마취과학회지

BACKGROUND: Segmental high thoracic epidural anesthesia and analgesia is now accepted as a popular technique for thoracic and breast surgeries, as well as post operative pain relief. However, a high thoracic epidural puncture is technically difficult, which can cause neurological complications. Having prior knowledge of the distance from the skin to the thoracic epidural space may be helpful for the prevention of complications during this procedure. This study was undertaken to evaluate the distance from the skin to the thoracic epidural space and the insertion angle of the Tuohy needle, as measured using a protractor, and to determine any potential relationship between a patient's height, weight and BMI (body mass index) with the calculated distance on the preoperative chest CT and the distance from the skin to the epidural space in 50 women undergoing a mastectomy. METHODS: In the sitting position, using a mid-line approach, the T4-5 epidural depth was measured in 50 mastectomy patients after the block had been successfully confirmed. The patient's age, height, weight and BMI, as well as the calculated distance on the preoperative chest CT were then checked. RESULTS: The distance from the skin to the thoracic epidural space at the T4-5 intervertebral level and insertion angle were 5.59 +/- 1.26 cm and 54.40 +/- 12.12 degrees, respectively. A significant correlation was found between the epidural depth and, the weight, BMI and calculated distance on the preoperative chest CT. CONCLUSIONS: The distance from the skin to the thoracic epidural space showed significant relationships with the weight, BMI and calculated distance on the preoperative chest CT.

Prediction of the Distance from Skin to Mid-Thoracic Epidural Space by Computed Tomography / 대한마취과학회지

BACKGROUND: Although thoracic epidural analgesia is a common practice in neuroaxial blockade for effective post-operative pain relief especially in major abdominal or thoracic surgery, difficult access to the thoracic epidural space is a frequent problem and can cause neurological complications like spinal cord injury and total spinal block. To minimize complications, we should to guess the distance for thoracic epidural space before this procedure. METHODS: One hundred fifty patients having preoperative upper abdominal computed tomography (CT) for diagnosis of their disease presented to major abdominal operation requiring mid-thoracic epidural analgesia for postoperative pain relief. The patient was placed in the sitting position and the levels of T7 and T8 spinous processes were identified. Using a paramedian approach with loss of resistance technique, when the insertion angles of Tuohy needle was measured by a protractor; inward angle (alpha) to the sagittal plane and downward angle (beta) to the transverse section of the spine. Entry of the needle into the epidural space, actual length (A) of the needle was marked and then measured with a ruler. Reviewing the abdominal CT films using the Picture Archiving and Communication System (PACS), the distance (B) from epidural space to skin on the transverse CT plane was measured at the corresponding to T7-T8 seemed to the level of the lowest scapular. The estimated length (Ac) of the skin to the epidural space was calculated by principle of trigonometry with alpha, beta and B. RESULTS: Mean (SD) age, height, weight, BMI were 56 (11) yr, 164 (6.9) cm, 61 (11.5) kg, and 37 (6.2) kg/m2, respectively. The A, B, Ac value and alpha, beta were 5.4 (0.77), 4.3 (0.76), 5.4 (0.85), 12 (3.4)o, 33 (9.6)o. There were significant correlation of both actual length of the needle and the estimated distance on CT film. Actual length of the needle tended to have 1.25 times longer than the estimated distance on CT film. There were also significances both A and weight, BMI, but not age, height. CONCLUSIONS: The distance from epidural space to skin measured on the transverse CT plane may be helpful as a guide for mid-thoracic epidural catheter insertion.

The Evaluation of Epidural Depth at L3-4 and L4-5 Using Magnetic Resonance Imaging and its Relationship to BMI / 대한마취과학회지

BACKGROUND: This study was performed to evaluate lumbar epidural depth using two methods, and to identify the correlation between epidural depth and body mass index (BMI). METHODS: The anatomy of the lumbar epidural space was evaluated using MRI images in 124 patients (93 male and 31 female patients). Epidural depth was measured from the skin to the center of the posterior epidural space at the L3-4 and L4-5 level using two methods (in a parallel line to the lumbar spinous process [EP-I] and in a vertical line to the long axis of the spine [EP-II]). RESULTS: The mean +/- SD of epidural depth by EP-I was 4.82 +/- 1.16 cm at L3-4 and 5.08 +/- 1.08 cm at L4-5, and depth by EP-II was 4.18 +/- 0.97 cm at L3-4 and 4.78 +/- 1.02 cm at L4-5. The epidural depths were 3.71 to 4.37 cm (L3-4) and 4.36 to 4.65 cm (L4-5) in normal weight patients, 4.29 to 4.86 cm (L3-4) and 4.79 to 5.06 cm (L4-5) in overweight patients, and 5.16 to 5.87 cm (L3-4) and 5.79 to 6.16 cm (L4-5) in obese patients. CONCLUSIONS: Epidural depth showed a close correlation with BMI, but not with sex.

A Study of Lumbar (L3-4, L4-5) Epidural Depth using Magnetic Resonance Imaging and its Correlation to Physical Measurements / 대한마취과학회지

BACKGROUND: This study was performed to evaluate the correlations between lumbar epidural depth by MRI and physical measurements. METHODS: The anatomy of the lumbar epidural space was evaluated using MRI scans of 121 patients (93 male and 31 female). Epidural depth was measured from the skin to the center of the posterior epidural space at the L3-4 and L 4-5 levels by two methods (in a parallel line to the lumbar spinous process [SKEP I] and in a vertical line to the long axis of the spine [SKEP II]). Physical measurements such as weight, height, foot size, and waist were measured, other physical measurements such as the Ponderal index (PI), body mass index (BMI), and obesity (Broca's index) were calculated. RESULTS: Significant correlations between depth from the skin to the posterior epidural space were found for Ponderal index (PI), body mass index (BMI), obesity (Broca's index), weight, waist circumference, height, and foot size. The depth from the skin to the supraspinous ligament correlated with BMI, obesity (Broca's index), PI, weight, and waist circumference. The depth from the supraspinous ligament to the posterior epidural space were found to correlate with height and foot size. CONCLUSIONS: PI had a higher predictive value for epidural depth than the other physical measurements.

Distance from Skin in the Lumbar Epidural Space in Korean Adult Male / 대한마취과학회지

The distance fmm skin to the lumber epidural space was measured in 60 male patients receiving epidural analgesia. The mean distance was found to be 4.45cm. The epidural depths were identified most frequently at 4.0 to 4.5cm deep and over 90% of total cases were less than 5.5cm deep. The epidural depths had correlations with weight and PI(P < 0.001), but not correlated with height.

The Measurement of Distance from Skin to the Epidural Space in Parturients / 대한마취과학회지

Lumber epidural analgesia is a well established method of providing pain relief during labor. Placement of a needle in the epidural space is probably one of the more tephnically demanding procedures which are performed by anesthesiologists. Two-hundred-thirty-four women receiving epidural analgesia during labor were studied. The distance from skin to the epidural space was measured with Portex disposable epidural needle marked at 1 cm intervals. The mean distance was found to be 4.18 cm. There was no correlation between distance from skin to the epidural space and height, hut was signifieant correlation with weight(p<0.001). The epidural depths were identified most frequently at 3 to 4 cm deep and 84.2% of total cases were less than 5 cm deep. This study suggests that, if the epidural space has not been identified within a depth of 6 cm, redirection or reinsertion of the needle should be considered.

A Study on the Distance from the Skin to the Lumbar Epidural Space in Korean Obstetric Population / 대한마취과학회지

The distance from the skin to the lumbar epidural space was measured in 87 women undergoing cesarean section(C/S) and 36 patients undergoing total abdominal hysterectomy(TAH) to compare with the C/S group. The patients age, height, most recent antenatal or preopertive weight, and shoe size were obtained before measuring the epidural depth. The PI(ponderal index) was caculated by dividing weight(kg) by height(m). In patients undergoing total hysterectomy, the mean distance was found to be 4.42 cm, which correlated with weight and PI (p<0.05), but height and shoe size had no significant effect on this distance. In women undergoing cesarean section, the mean distance was found to be 4.48 cm which had no correlation with any other measurements.

A Study on the Distance from the Skin to the Lumbar Epidural Space in Korean Obstetric Population / 대한마취과학회지

The distance from the skin to the lumbar epidural space was measured in 87 women undergoing cesarean section(C/S) and 36 patients undergoing total abdominal hysterectomy(TAH) to compare with the C/S group. The patients age, height, most recent antenatal or preopertive weight, and shoe size were obtained before measuring the epidural depth. The PI(ponderal index) was caculated by dividing weight(kg) by height(m). In patients undergoing total hysterectomy, the mean distance was found to be 4.42 cm, which correlated with weight and PI (p<0.05), but height and shoe size had no significant effect on this distance. In women undergoing cesarean section, the mean distance was found to be 4.48 cm which had no correlation with any other measurements.