Relationship of abdominal circumference and trunk length with spinal anesthesia level in the term parturient

Relationship of Abdominal Circumference and Trunk Length With Spinal Anesthesia Block Height in Geriatric Patients Undergoing Transurethral Resection of Prostate

INTRODUCTION

Spinal anesthesia is commonly used for various surgical procedures. Prediction of spinal anesthesia block height is always a challenging task for anesthetists. Higher than desired levels of spinal anesthesia blocks are associated with serious side effects, while inadequate block height does not provide satisfactory surgical anesthesia. In this study, we observed the relationship between the ratio of trunk length (TL) and square of the abdominal circumference (AC²) and spinal anesthesia sensory block height in geriatric patients undergoing transurethral resection of the prostate (TURP).

MATERIAL & METHODS

This is a cross-sectional study conducted at the Aga Khan University Hospital Karachi, Pakistan, on geriatric patients undergoing TURP under spinal anesthesia. Forty-three elderly patients (American Society of Anaesthesiology level I-III) between 60 and 80 years were recruited for the study. In hospital wards, trunk length (TL) and abdominal circumference were recorded before the procedure. In the operating rooms, spinal anesthesia was performed at L3-L4 intervertebral space with 0.5% hyperbaric bupivacaine 10mg (2mls). Block height was measured by the placement of ice pads at different dermatomes. Spearman rank correlation coefficient was used to analyze the physical parameters (TL/AC²) and spinal anesthesia block height.  Results: The ratio of trunk length and square of the abdominal circumference (TL/AC²) correlates with spinal anesthesia block height in geriatric patients, where the spearman rank correlation coefficient was r =-0.284 with p = 0.015.

CONCLUSION

The ratio of the long axis (TL) and transection area of the abdomen (AC²), which coincides with (TL/AC²), correlated with spinal anesthesia sensory block height. Hence, elderly patients with a low TL/AC² ratio will have higher block height after spinal anesthesia.

The impact of height on the spread of spinal anesthesia and stress response in parturients undergoing caesarean section: a prospective observational study

Background

The spread of spinal anesthesia was influenced by many factors, and the effect of body height on spinal anesthesia is still arguable. This study aimed to explore the impact of height on the spread of spinal anesthesia and the stress response in parturients.

Methods

A total of ninety-seven parturients were allocated into two groups according to their height: the shorter group (body height was shorter than 158 cm) and taller group (body height was taller than 165 cm). Spinal anesthesia was performed with the same amount of 12 mg plain ropivacaine in mothers of different heights. The primary outcome of the study was the success or failure of the spinal anesthesia. The secondary outcomes of the study were stress response, time to T6 sensory level, the incidence of hypotension, the satisfaction of abdominal muscle relaxation and patient VAS scores.

Results

The rate of successful spinal anesthesia in the shorter group was significantly higher than that in the taller group (p = 0.02). The increase of maternal cortisol level in the shorter group was lower than that in the taller group at skin closure (p = 0.001). The incidence of hypotension (p = 0.013), time to T6 sensory block (p = 0.005), the quality of abdominal muscle relaxation (p <  0.001), and VAS values in stretching abdominal muscles and uterine exteriorization (p <  0.001) in the shorter group were significantly different from those in the taller group. Multivariate analysis showed that vertebral column length (p <  0.001), abdominal girth (p = 0.022), amniotic fluid index (p = 0.022) were significantly associated with successful spinal anesthesia.

Conclusions

It’s difficult to use a single factor to predict the spread of spinal anesthesia. Patient’s vertebral column length, amniotic fluid index and abdominal girth were the high determinant factors for predicting the spread of spinal anesthesia.

Trials registration

ChiCTR-ROC-17012030 (Chictr.org.cn), registered on 18/07/2017.

Relationship between Abdominal Circumference and Incidence of Hypotension during Cesarean Section under Spinal Anesthesia

Background

Enlarged uterus can compress the inferior vena cava and cause hypotension when lying supine. Previous studies have shown a positive association between the abdominal circumference and size of the uterus. Therefore, the aim of this study was to evaluate the relationship between abdominal circumference and incidence of hypotension during cesarean section under spinal anesthesia.

Methods

The study cohort comprised women undergoing cesarean section under spinal anesthesia. Patients were divided into two groups according to the median abdominal circumference (<101 cm and ≥101 cm). Hypotension was defined as a systolic blood pressure of <90 mmHg or mean arterial pressure of <65 mmHg. The primary outcome of this study was the relationship between the incidence of hypotension and the abdominal circumference after spinal anesthesia in term pregnant women.

Results

The study cohort comprised 100 women. The incidence of hypotension did not differ between the groups (71.42% in the smaller vs. 78.43% in the larger abdominal circumference group, p=0.419). However, the decrease in mean arterial pressure and its percentage decrease from baseline were greater in the larger than in the smaller abdominal circumference group (change in mean arterial pressure: 28.33 mmHg (18.66-33.67) in the smaller vs. 36.67 mmHg (23.34-43.34) in the larger abdominal circumference group, p=0.004; percentage decrease: 31.41% (22.74-39.22) in the smaller vs. 38.47% (28.00-44.81) in the larger abdominal circumference group, p=0.022).

Conclusions

Large abdominal circumference in pregnancy is associated with greater decreases in mean arterial pressure from baseline. However, the incidence of hypotension defined by standard criteria did not differ between larger and smaller abdominal circumference groups.

The influence of Body Roundness Index on sensorial block level of spinal anaesthesia for elective caesarean section: an observational study

In this prospective trial, we investigate the effectiveness of maternal Body Roundness Index in predicting the spread of spinal anaesthesia and vasopressor requirement in parturients receiving spinal anaesthesia during the elective caesarean section. We prospectively enrolled 175 parturients. Spinal anaesthesia performed with 10 mg 0.5% hyperbaric bupivacaine at the L3-L4 intervertebral space and the optimal cut-off points of the BRI evaluated as 6.59 by receiver operating characteristic analysis calculating area under the curve. Parturients were divided into two groups with BRI <6.59 and BRI ≥6.59 for analyses. Multivariate logistic regression analysis was used to test for a relationship between variables and maximum sensory block level and vasopressor requirement. BRI was found as an independent risk factor associated with maximum sensory block level (OR = 1.378, 95% CI: 1.125-1.687, p = 0.002). Hypotension and bradycardia events after spinal anaesthesia was not associated with BRI and other variables. The present study indicates that BRI was a practical tool to predict spinal drug distribution in term parturients undergoing caesarean delivery.Impact statementWhat is already known on this subject? Spinal anaesthesia is a commonly used anaesthetic technique for the caesarean section. However, the spinal drug distribution is highly unpredictable. Anthropometric variables may predict the intrathecal drug distribution in parturients. Body Roundness Index (BRI) captures body circumference regarding height to predict body fat percentage, consider the shape of the human body as an ellipse. An ellipsoid body shape might affect the spread of spinal anaesthesia.What do the results of this study add? Our results show that the BRI was as an independent risk factor associated with maximum sensory block level in term parturients undergoing caesarean delivery.What are the implications of these findings for future clinical practice and/or further research? A future study would present the possibility to design a formula for the exact amount of local anaesthetic to be used in spinal anaesthesia with the aid of maternal BRI.

The effects of uterine size with or without abdominal obesity on spinal block level and vasopressor requirement in elective cesarean section: a prospective observational study

Background/aim

Hypotension is a serious complication caused by spinal anesthesia that places both the mother and fetus at increased risk. We aimed to investigate the effects of uterine size with or without abdominal obesity on sensory block level of pregnant women receiving spinal anesthesia.

Materials and methods

This study included 125 term parturients who underwent cesarean section. Motor and sensory block characteristics, the distance between the symphysis pubis and the fundus (SPF), the distance between the symphysis pubis and the xiphoid (SPX), newborn and placental weights, adverse effects, and doses of ephedrine were recorded.

Results

Sensory block level and ephedrine dose were significantly correlated with the SPX and the combined newborn and placenta weights (P < 0.05). The incidence of hypotension was related to the SPX and the combined newborn and placenta weight (P < 0.05). There was no correlation between the SPF and sensory block level or ephedrine dose. The sensory block level was higher for patients who had greater SPX values and higher combined newborn and placenta weights. The incidence of hypotension and the ephedrine dose were also higher in these subjects.

Conclusion

SPX values and combined newborn and placenta weights are more predictive of sensory block level than SPF values in parturients receiving spinal anesthesia.

Correlation of Symphysiofundal Height and Abdominal Girth with the Incidence of Hypotension in Cesarean Section Under Spinal Anesthesia using Bupivacaine with Fentanyl as Adjuvant: A Clinical Study

Background and Aims:

A decreased lumbosacral subarachnoid space volume is a major factor in cephalad intrathecal spread of local anesthetic in term parturients due to compressive effect of the gravid uterus. The aim of this study was to assess the relationship of symphysiofundal height (SFH) and abdominal girth (AG) with the incidence of hypotension and the highest level of sensory blockade.

Settings and Design:

This study was a prospective observational study.

Materials and Methods:

Ninety parturients under the American Society of Anesthesiologists physical status class II within the age range of 20–30 years, weighing between 60 and 65 kg, and height between 150 and 155 cm were studied, and the SFH and AG of all parturients had been measured just before spinal anesthesia. Hyperbaric bupivacaine 9 mg with 12.5 μg intrathecal fentanyl was administered for subarachnoid block. The incidence of hypotension and the highest level of sensory block were assessed.

Statistical Analysis:

Correlation analysis (Spearman's rank test) was applied to analyze the data, and P < 0.05 was considered to be statistically significant.

Results:

The incidence of hypotension was higher with increasing SFH (16.9% with SFH of 30–35 cm, 78.37% with SFH of 36–40 cm; correlation coefficient ρ =0.338) and with increasing AG (5.3% with AG between 85 and 89 cm, 35.7% with AG 90–94 cm, 62.8% with AG 95–99 cm; ρ =0.341), and both were statistically significant (P < 0.001). There was a statistically significant correlation between increasing SFH and maximum sensory block achieved (ρ =0.157, P < 0.001). There was increased level of sensory blockade with increased AG but was not statistically significant (ρ =0.011, P = 0.32).

Conclusion:

In term parturients undergoing cesarean section under spinal anesthesia, the SFH has a significant positive correlation with the incidence of hypotension and ascent of spinal anesthesia. AG also has a positive correlation with the incidence of hypotension but is not significant with the ascent of spinal anesthesia.

Correlation between Weight of the Baby and the Level of Sensory Blockade in Spinal Anaesthesia for Caesarean Section: An Observational Study

Background

The spread of local anaesthetics during spinal anaesthesia is affected by various factors and can be unpredictable especially in parturients undergoing caesarean section. Factors like abdominal girth, symphysis fundal height etc have to studied to know their impact on level of sensory blockade. We hypothesized a study to find any correlation between weight of the baby and the level of sensory blockade.

Methods

46 parturients posted for elective caesarean section belonging to American Society of Anaesthesiologists (ASA) physical status 1 and 2 were included in the study. Maternal height and weight were noted down before entering operation theatre. All patients were instituted subarachnoid block with 2 cc of 0.5% of hyperbaric bupivacaine in sitting position. Level of sensory blockade was assessed with pin prick along midline of the patient every min till 5^th minute and 5 minutes till 15^th minute. The birth weight of baby was recorded soon after delivery.

Results

The weight of the baby and height of the mother were correlated with the sensory blockade of T4. The number of babies weighing more than 3.5 kgs were 3 in our study out of which 2 babies were associated with maximum sensory blockade at 15^th minute. It amounts to 66.7% when compared with 14.7% in babies weighing 2.5 to 3.5 kgs which is suggestive of significance ('P' value of 0.093).

Conclusion

There is no statistically significant correlation between weight of the baby and the level of sensory blockade.

Intra-abdominal pressure, vertebral column length, and spread of spinal anesthesia in parturients undergoing cesarean section: An observational study

Background

In parturients with increased physiologically intra-abdominal pressure (IAP) and a short stature, a greater cephalad spread of spinal anesthesia is often observed after a fixed amount of plain bupivacaine is administered. Therefore, we designed this prospective study to test whether IAP and vertebral column length (VCL) were predictors of spinal spread in parturients undergoing a cesarean section.

Methods

A total of 113 parturients, all undergoing elective cesarean sections with single-shot spinal anesthesia, were enrolled. The L3-L4 interspace was entered, and 2 mL of 0.5% plain bupivacaine was injected into the subarachnoid space. Upon loss of temperature sensation at the T4 level, IAP was measured through a bladder catheter while the patient was in the supine position with a 10°left lateral tilt. Parturient demographic variables, including age, height, weight, IAP, and VCL were recorded. Linear regressions and multiple regressions were performed to analyze the relationships between parturient variables and the spread of spinal anesthesia.

Results

A total of 109 parturients were included in the analysis. Linear regression analysis showed a significant univariate correlation of height, weight, body mass index (BMI), IAP, and VCL with cephalad spread (all P< 0.004). Multiple linear regression analysis showed that IAP and VCL were the key determinants of spinal spread (both P < 0.0001), where as exclusion of age, weight, and height did not change the result (all P> 0.209).

Conclusions

Our data indicated that IAP and VCL were significant predictors of intrathecal spread of plain bupivacaine, and there was a positive association between IAP and abdominal girth in term parturients.

Abdominal girth and vertebral column length aid in predicting intrathecal hyperbaric bupivacaine dose for elective cesarean section

Currently, there is no consensus on how to determine the optimal dose of intrathecal bupivacaine for an individual undergoing an elective cesarean section. In this study, we developed a regression equation between intrathecal 0.5% hyperbaric bupivacaine volume and abdominal girth and vertebral column length, to determine a suitable block level (T5) for elective cesarean section patients.In phase I, we analyzed 374 parturients undergoing an elective cesarean section that received a suitable dose of intrathecal 0.5% hyperbaric bupivacaine after a combined spinal-epidural (CSE) was performed at the L3/4 interspace. Parturients with T5 blockade to pinprick were selected for establishing the regression equation between 0.5% hyperbaric bupivacaine volume and vertebral column length and abdominal girth. Six parturient and neonatal variables, intrathecal 0.5% hyperbaric bupivacaine volume, and spinal anesthesia spread were recorded. Bivariate line correlation analyses, multiple line regression analyses, and 2-tailed t tests or chi-square test were performed, as appropriate. In phase II, another 200 parturients with CSE for elective cesarean section were enrolled to verify the accuracy of the regression equation.In phase I, a total of 143 parturients were selected to establish the following regression equation: YT5 = 0.074X1 - 0.022X2 - 0.017 (YT5 = 0.5% hyperbaric bupivacaine volume for T5 block level; X1 = vertebral column length; and X2 = abdominal girth). In phase II, a total of 189 participants were enrolled in the study to verify the accuracy of the regression equation, and 155 parturients with T5 blockade were deemed eligible, which accounted for 82.01% of all participants.This study evaluated parturients with T5 blockade to pinprick after a CSE for elective cesarean section to establish a regression equation between parturient vertebral column length and abdominal girth and 0.5% hyperbaric intrathecal bupivacaine volume. This equation can accurately predict the suitable intrathecal hyperbaric bupivacaine dose for elective cesarean section.

Abdominal girth, vertebral column length and spread of intrathecal hyperbaric bupivacaine in the term parturient

BACKGROUND

We aimed to test whether abdominal girth and vertebral column length were predictors of spinal hyperbaric bupivacaine spread in term parturients.

METHODS

A total of 128 parturients having elective caesarean section under spinal anaesthesia were enrolled. Combined spinal-epidural anaesthesia was performed at the L3/4 interspace, confirmed by ultrasonography. Two mL of 0.5% hyperbaric bupivacaine was injected intrathecally and spinal spread assessed at three-minute intervals. If loss of discrimination of pinprick sensation at the T6 level was not obtained within 15min after injection, 5mL of 2% lidocaine was administered epidurally. Correlation and multiple linear regression were used to analyse the relationship between patient variables, including age, height, weight, abdominal girth, vertebral column length and neonatal biparietal diameter, and the spread of spinal anaesthesia.

RESULTS

Two parturients were excluded. Significant univariate correlation with spinal spread existed for height, weight, abdominal girth and vertebral column length (r=-0.446, 0.201, 0.372, P<0.711, respectively, all P<0.05). Multiple linear regression analysis showed that parturients' abdominal girth and vertebral column length were the key determinants of spinal spread (both P<0.0001). The adjusted R² was 0.742 for the regression equation between abdominal girth, vertebral column length and height of block.

CONCLUSION

Parturient abdominal girth and vertebral column length have significant predictive value in determining the cephalad spread of spinal anaesthesia with hyperbaric bupivacaine in term parturients.

Effect of Concentration on Median Effective Dose (ED50) for Motor Block of Intrathecal Plain Bupivacaine in Elderly Patients

Background

The aim of the study was to determine the median effective dose (ED₅₀) for motor block of various concentrations of intrathecally administered plain bupivacaine.

Material/Methods

Between 2011 and 2013, 64 patients aged ≥70 years, undergoing transurethral, or lower limb surgery with combined spinal and epidural anesthesia in a single hospital were enrolled. The patients were randomized into 3 groups to receive intrathecal 0.75% bupivacaine (Group 1), 0.375% bupivacaine (Group 2) or 0.25% bupivacaine (Group 3). Spinal anesthesia was achieved using injections of up-and-down doses of 0.75%, 0.375%, or 0.25% plain bupivacaine. The first patient in each group received 7.5 mg bupivacaine, and the testing interval was set at 0.75 mg. The efficacy of motor block in both legs was determined using a modified Bromage and a hip motor function scale. The ED₅₀ for motor block was estimated according to the Dixon’s up-and-down method.

Results

The ED₅₀ for motor block of bupivacaine was 6.10 (95% CI 5.58–6.66) mg in Group 1, 6.04 (95% CI 5.82–6.28) mg in Group 2, and 5.43 (95% CI 5.19–5.67) mg in Group 3. There were significant differences in the ED₅₀ for motor block among the groups (P=0.008).

Conclusions

The ED₅₀ doses for motor block with 3 bupivacaine concentrations were significantly different in elderly patients; the ED₅₀ dose of 0.75% bupivacaine being significantly higher than that of 0.25% bupivacaine.

Abdominal circumference but not the degree of lumbar flexion affects the accuracy of lumbar interspace identification by Tuffier's line palpation method: an observational study

Background

Lumbar puncture for spinal or epidural anesthesia is commonly performed by palpating bony landmarks, but identification of the desired intervertebral level is often inaccurate. It is unclear whether such inaccuracy is related to patient factors, such as body mass index and degree of lumbar flexion. We hypothesized that overweight patients and patients with less of an ability to hyperflex their lumbar spines are prone to inaccurate lumbar spinous intervertebral level identification.

Methods

52 adult volunteers were included in this study. 7 anesthesiologists with different years of experience identified and marked subjects’ levels of the iliac crests, then marked the presumed interspaces. Lumbar X-ray was then performed with metal markers, and actual radiographic findings were identified and compared to the initial markings.

Results

Patients with larger abdominal circumferences (mean (SD), 94.0(12.1) cm), higher body mass indices (25.9(3.9) kg/m²), and aged between 50 and 70 years old had lumbar interspaces that were higher than the presumed level; patients with smaller abdominal circumferences (82.8(13.5) cm) and lower body mass indices (21.6(4.1) kg/m²) had intervertebral levels that were lower than the presumed level. Cobb’s angle, indicating the degree of lumbar flexion, did not affect the accuracy obtained.

Conclusions

Patients’ abdominal circumference, body mass index, and age are factors that may impact the accuracy of lumbar level identification. Tuffier’s line, as identified by palpation, does not seem to be a reliable landmark for proper lumbar interspace identification in all cases.