Saudi Journal of Anaesthesia

CASE REPORT
Year
: 2023  |  Volume : 17  |  Issue : 1  |  Page : 110--112

The lumbar subcutaneous fat gradient in spinal anesthesia seen for morbidly obese patient with pre-procedure ultrasonography – A case report


Hiroki Nakamura, Shuhei Hisago, Shunsuke Ishitsuka 
 Department of Anesthesiology, Tsuchiura Kyodo Hospital, Tsuchiura, Ibaraki, Japan

Correspondence Address:
Hiroki Nakamura
Department of Anesthesiology, Tsuchiura Kyodo Hospital, 4-1-1 Otsuno, Tsuchiura, Ibaraki 300-0028
Japan

Abstract

It has been reported that pre-procedure ultrasonography rises the success rate of spinal anesthesia in obese patients. In this article, we performed spinal anesthesia for morbidly obese patient with pre-procedure ultrasonography. And recognizing the lumbar subcutaneous fat gradient in morbidly obese patient was the key to success. A cesarean section was scheduled for a primigravida in her 30 s with BMI 61 kg/m2. The lumbar spine was not palpable. Pre-procedure ultrasonography revealed lumbar subcutaneous tissue getting thicker caudally in the sagittal view. Considering this fact, we adjusted the puncture site and succeeded. Postoperative complications were not observed. The pre-procedure ultrasonography is effective even in morbidly obese patients. It is important to recognize the lumbar subcutaneous fat gradient, the so-called back fat slope, for spinal anesthesia in obese patients.



How to cite this article:
Nakamura H, Hisago S, Ishitsuka S. The lumbar subcutaneous fat gradient in spinal anesthesia seen for morbidly obese patient with pre-procedure ultrasonography – A case report.Saudi J Anaesth 2023;17:110-112


How to cite this URL:
Nakamura H, Hisago S, Ishitsuka S. The lumbar subcutaneous fat gradient in spinal anesthesia seen for morbidly obese patient with pre-procedure ultrasonography – A case report. Saudi J Anaesth [serial online] 2023 [cited 2023 Mar 22 ];17:110-112
Available from: https://www.saudija.org/text.asp?2023/17/1/110/364875


Full Text



 Introduction



Spinous process palpation is difficult in morbidly obese patient which makes spinal anesthesia tricky.[1] In recent years, it has been reported that the success rate of spinal anesthesia in obese patients is increased with pre-procedure ultrasonography.[2] A case report of lumbar puncture using pre-insertion ultrasound in morbidly obese patient more than BMI 50 was reported.[3] Here, we successfully performed spinal anesthesia by revealing the lumbar subcutaneous fat gradient with pre-procedure ultrasound in BMI 61 parturient.

 Case History



A cesarean section was scheduled for a primigravida in her 30s with BMI 61 kg/m2 at 40 weeks 5 days due to cephalopelvic disproportion. The patient's height, weight were 167 cm, 170.2 kg. Her type 2 diabetes mellitus was controlled with insulin. On physical examination, her lumbar spine was not palpable. Other examinations were unremarkable. After entering the operating room, a sitting position was assumed by her [Figure 1]. Sacrum and the 3rd to 5th lumbar spinous process were detected with ultrasound convex probe (SONIMAGE HS2, KONICA MINOLTA) and the middle line and spinous process were marked [Figure 2]. The distance to subarachnoid space was speculated to about 80–90 mm referencing a transverse view. Thus, a lumbar puncture with a 23–25 G and 11-mm type P, FD (Hakko, Japan) was started. After several times of trials, we used ultrasound again and identified the space between lumbar spinous process and lumbar subcutaneous tissue getting thicker caudally in the sagittal view [Figure 3]. This indicated that the lumbar vertebrae and the skin are not parallel. We adjusted puncture angle toward the cephalic side [From dotted arrow to double line arrow in [Figure 4]]. As a result, a back flow of clear cerebrospinal fluid was confirmed at the depth of 95 mm. The patient did not have abnormal sensation in her lower limbs during procedure. 10.5 mg of 0.5% hyperbaric marcaine, 10 μg of fentanyl, and 100 μg of morphine was administered. The loss of cold sensation on the right and left, less than the 4th thoracic vertebral level was confirmed. The operation was finished without problems and there were no postoperative complications. Written informed consent was obtained from the patient for the publication of this case report and accompanying images.{Figure 1}{Figure 2}{Figure 3}{Figure 4}

 Discussion



Obese patients are found to be difficult to intubate.[4] Furthermore, unexpected difficult intubation can occur in over 136 kg parturient.[5] In this case, mother and fetus are not in a state of urgency. Therefore, spinal anesthesia was chosen primarily. Morbid obesity can make spinal anesthesia difficult and also increases the number of punctures required for effective anesthesia.[1] Pre-procedure ultrasonography enables us to identify the interspace for needle placement and also estimate the depth of the subarachnoid space in patients whose anatomic landmarks are difficult to palpate. The success rate of spinal anesthesia in obese patient therefore rises with this pre-scanning.[2] Although there are only a few case reports of spinal anesthesia with pre-insertion ultrasound in morbidly obese patient, Morimoto et al.[3] reports that they have succeeded in lumbar puncture with pre-scanning in BMI 50 woman. In our case, detecting subcutaneous fat tissue getting thick to caudal was the key to success. Mahmoudi et al.[6] reported that the distance between the skin and the spinal canal, between the 3rd and 4th, 4th and 5th lumbar vertebrae, and 5th lumbar vertebrae and 1st sacral vertebrae is proportional to BMI and increases as it goes caudally. In our case, [Figure 3] shows that the distance between the lumbar vertebrae and the skin increased caudally which suggests that the lumbar vertebrae and the skin are not parallel when the patient is seen from the side, but oblique caudally and spreads out [Figure 4]. If the puncture is done at right angle to the skin [dotted arrow in [Figure 4]], the needle will not pass through. Therefore, the adjusted puncture angle toward the cephalic side [double line arrow in [Figure 4]], was considered successful. Several studies have shown that ultrasonography can help with spinal anesthesia in patients with difficult anatomy such as severe obesity, lumbar scoliosis, ankylosing spondylitis, and post-lumbar spine surgery.[7] However, there have been few reports on the anatomical changes in lumbar subcutaneous fat, and no reports were found of these changes being noted on pre-procedure ultrasonography. We call this structure the back fat slope. It is important to recognize the back fat slope and perform lumbar puncture even when using the landmark method without pre-procedure ultrasonography. In this study, we were not able to perform MRI or CT imaging, and the detailed anatomy is unknown. In addition, ultrasound-guided spinal anesthesia was difficult so the actual puncture angle could not be verified. Further research is required. In this case, spinal anesthesia was successfully achieved, and the pre-procedure ultrasonography is seemingly effective even in morbidly obese patients. In addition, it is necessary to recognize the subcutaneous fat gradient in the lumbar region, that is, the back fat slope for spinal anesthesia in obese patients.

Declaration of patient consent

The authors certify that they have obtained all appropriate patient consent forms. In the form, the patient has given her consent for her images and other clinical information to be reported in the journal. The patient understands that her name and initials will not be published and due efforts will be made to conceal identity, but anonymity cannot be guaranteed.

Acknowledgments

I would like to thank the medical staff at Tsuchiura Kyodo Hospital.

Key messages

The lumbar subcutaneous fat gradient is important to succeed spinal anesthesia in obese patients.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.

References

1An X, Zhao Y, Zhang Y, Yang Q, Wang Y, Cheng W, et al. Risk assessment of morbidly obese parturient in cesarean section delivery: A prospective, cohort, single-center study. Medicine (Baltimore) 2017;96:e8265.
2Li M, Ni X, Xu Z, Shen F, Song Y, Li Q, et al. Ultrasound-assisted technology versus the conventional landmark location method in spinal anesthesia for cesarean delivery in obese parturients: A randomized controlled trial. Anesth Analg 2019;129:155-61.
3Morimoto Y, Ihara Y, Shimamoto Y, Shiramoto H. Use of ultrasound for spinal anesthesia in a super morbidly obese patient. J Clin Anesth 2017;36:88-9.
4Saasouh W, Laffey K, Turan A, Avitsian R, Zura A, You J, et al. Degree of obesity is not associated with more than one intubation attempt: A large center experience. Br J Anaesth 2018;120:1110-6.
5Hood DD, Dewan DM. Anesthetic and obstetric outcome in morbidly obese parturients. Anesthesiology 1993;79:1210-8.
6Mahmoudi K, Joon Y, Kihira S, Goldstein J, Garvey KL, Platt S, et al. Body mass index correlates with skin to spinal canal distance: A large retrospective single-center study. J Neuroimaging 2020;30:896-900.
7Yoo S, Kim Y, Park SK, Ji SH, Kim JT. Ultrasonography for lumbar neuraxial block. Anesth Pain Med (Seoul) 2020;15:397-408.