Hidden blood loss during perioperative period and the influential factors after surgery of thoracolumbar burst fracture: A retrospective case series

Hidden blood loss in three different endoscopic spinal procedures for lumbar disc herniation

Purpose

This study compared hidden blood loss (HBL) among three different endoscopic spinal procedures and investigated its risk factors.

Patients and methods

This single-centre retrospective analysis collected data from consecutive hospitalized patients with single-segment lumbar disc herniation (LDH) undergoing unilateral biportal endoscopic discectomy (UBE), percutaneous endoscopic transforaminal discectomy (PETD), or percutaneous endoscopic interlaminar discectomy (PEID) from December 2020 to October 2022. HBL was calculated using Nadler's and Gross's formulas. The authors used Pearson's or Spearman's correlation analysis to explore the relationship between patient characteristics and HBL. Multivariate linear regression analysis was used to identify independent risk factors for HBL.

Results

In total, 122 consecutive patients (68 females and 54 males) were enroled in this study. The average HBL was 381.87±218.01 ml in the UBE group, 252.05±118.44 ml in the PETD group and 229.63±143.9 ml in the PEID group (P<0.05). Pearson's or Spearman's correlation analysis showed that operative time, preoperative haemoglobin, preoperative haematocrit, and preoperative Albumin (ALB) were correlated with HBL in the UBE group, while sex, age, operative time, postoperative ALB, and patients' blood volume (PBV) were related to HBL in the PETD group (P<0.05). Operative time and preoperative activated partial thromboplastin time were related to HBL in the PEID group (P<0.05). Multiple linear regression analysis showed a positive correlation between HBL and operative time in all three groups (P<0.001, P<0.001, P<0.05).

Conclusion

HBL was higher in the UBE group than in the PETD and PEID groups, and operative time may be a common risk factor for the three groups.

Application of supervised machine learning algorithms to predict the risk of hidden blood loss during the perioperative period in thoracolumbar burst fracture patients complicated with neurological compromise

Background

Machine learning (ML) is a type of artificial intelligence (AI) and has been utilized in clinical research and practice to construct high-performing prediction models. Hidden blood loss (HBL) is prevalent during the perioperative period of spinal treatment and might result in a poor prognosis. The aim of this study was to develop a ML-based model for identifying perioperative HBL-related risk factors in patients with thoracolumbar burst fracture (TBF).

Methods

In this study, single-central TBF patients were chosen. The medical information on patients, including clinical characteristics, laboratory indicators, and surgery-related parameters, was extracted. After comparing various ML model algorithms, we selected the best model with high performance. The model was validated using the internal validation set before performing recursive feature elimination (RFE) to determine the importance of HBL-related risk factors. The area under the receiver operating characteristic (AUC) curve, accuracy (ACC), sensitivity, and specificity were reported as critical model measures for evaluating predictive performance.

Results

In this study, 62 (38.5%) of the 161 TBF patients were positive for HBL. There was a significant statistical difference in age, body mass index (BMI), diabetes, hypertension, Beta (percentage of vertebral restoration), duration of operation, and other pre-operative laboratory indicators between the HBL-positive and HBL-negative groups. Nine ML-based models were built and validated, with the Random Forest model having the greatest AUC in both the training set (0.905) and internal validation set (0.864). Furthermore, following RFE, age, duration of operation, Beta, pre-operative fibrinogen (Fib), and activated partial thromboplastin time (APTT) were identified as the five main important risk factors in patients with TBF during the perioperative period.

Conclusion

In this study, we built and validated ML algorithms for an individualized prediction of HBL-related risk factors in the perioperative period of TBF. The importance of HBL-related risk factors could be determined, which contributes to clinicians' decision-making and improves perioperative management.

Substantially High Hidden Blood Loss in Oblique Lateral Interbody Fusion: Retrospective Case Series

Background and Objectives: Measured blood loss frequently underestimates true blood loss; this discrepancy is called hidden blood loss (HBL). The purpose of the present study was to measure HBL in oblique lateral interbody fusion (OLIF). Materials and Methods: Patients who underwent two-stage OLIF at our institute from September 2017 to September 2021 were retrospectively reviewed. Total blood loss (TBL) and HBL were calculated using the gross formula. The age, sex, body mass index (BMI), operation time, measured blood loss, the number of fused segments, hematocrit (HCT), anticoagulant or platelet medication, blood transfusion, days of hospitalization, pre-/postoperative Japanese Orthopedic Association (JOA) score, and JOA recovery rate were compared. Results: A total of thirteen patients were included in the study. The average age, BMI, number of fused segments, operation time, estimated blood loss, and blood transfusion were 69.5 years, 23.3, 2.5, 250 min, 122 mL, and 230 mL, respectively. Five patients received anticoagulant or platelet therapy. Days of hospitalization, pre-/postoperative JOA score, and JOA recovery rate were 14.9 ± 5.1, 19.9 ± 2.7, and 18.0 ± 43.4%, respectively. The TBL and HBL were 688 and 797 mL, respectively. Stepwise multiple regression analysis revealed that younger age (p = 0.01), female sex (p = 0.01), and number of fused segments (p = 0.02) were significantly associated with higher HBL. Conclusions: The HBL in OLIF was 797 mL, which was more than other previously reported procedures. Therefore, OLIF may not be less invasive in terms of HBL. Blood loss after surgery should be considered, especially when patients are younger, are female, and have a greater number of fused segments.

Hidden blood loss in extreme lateral interbody fusion for adult spinal deformity

BACKGROUND

Extreme lateral interbody fusion (XLIF) is often used with posterior spinal fixation (PSF) to treat adult spinal deformity (ASD). However, the amount of intraoperative blood loss (IBL) reported for XLIF may underestimate the total blood loss (TBL). The objective of this study was to determine the total perioperative blood loss in XLIF for ASD.

METHODS

We assessed 30 consecutive ASD patients with Schwab-SRS type L (mean age: 68.7 ± 8.2 years; mean follow-up 2.0 ± 1.3 years) who were treated by multilevel XLIF (mean, 2.5 ± 0.6 levels) followed by PSF after 3-5 days. We calculated the TBL after XLIF by the Gross equation, by hemoglobin (Hb) balance, and by the Orthopedic Surgery Transfusion Hemoglobin European Overview (OSTHEO) formula. We defined hidden blood loss (HBL) as the difference between the TBL and IBL. Pearson correlation, Spearman correlation, and multiple logistic regression analysis were performed to investigate the risk factors related to HBL.

RESULTS

Post-XLIF blood tests showed a significant decrease in the Hb (from 11.8 ± 1.1 mg/dl to 10.6 ± 1.1 mg/dl) and hematocrit (from 36.0 ± 3.2% to 32.5 ± 3.2%). Although the mean IBL was relatively small (33 ± 52 mL), we calculated the TBL as 291 ± 171 mL (Gross equation) and the HBL as 258 ± 168 mL by Gross equation, which was 8 times greater than the IBL on average. There was no difference in the results obtained using the three methods. Multiple logistic regression analysis indicated preoperative lumber lordosis was the risk factor of high HBL (Odds ratio = 1.085, 95%CI: 1.006-1.170, p = 0.035).

CONCLUSIONS

The HBL in XLIF was 8 times greater than the IBL. During the perioperative course of correction and fusion surgery for ASD with XLIF, surgeons need to pay attention not to underestimate the TBL.

Modified Hidden Blood Loss Based on Drainage in Posterior Surgery on Lumbar Stenosis Syndrome with Rheumatoid Arthritis

OBJECTIVE

Publications on hidden blood loss (HBL) after posterior lumbar interbody fusion (PLIF) for lumbar spine stenosis syndrome (LSS) have been reported, but the modified HBL (mHBL) was different from HBL obtained by classical formula and there are few studies on lumbar spine hemorrhage with rheumatoid arthritis (RA). Therefore, the aim of our study is to respectively evaluate the importance of hidden blood loss (HBL) and modified HBL (mHBL) after posterior lumbar interbody fusion (PLIF) in patients diagnosed with LSS and RA, to explore the correlation between RA activity and HBL as well as mHBL.

METHODS

A total of 61 patients (nine males and 52 females) diagnosed with LSS and RA who underwent PLIF were included. Data contained demographics, RA-related parameters such as duration of RA, Steinbrocker classification (used to evaluated RA activity), the disease-modifying anti-rheumatic drugs (DMARDs), osteoporosis and total knee arthroplasty; operation and hemorrhage parameters. Then HBL and mHBL were calculated by Gross formula and modified formula, respectively. Subgroup analysis on HBL and mHBL was performed based on gender, age (≤60 years and ˃60 years), different number of surgical segments (single segment, double segment, and ≥3 segments), and taking DMARDs or not. ANOVA analysis was performed on HBL and mHBL in different surgery segment number and Steinbrocker classification of RA. Independent sample t-test was used in comparison of gender and age, as well as in comparison between HBL and mHBL based on whether the patient took DMARDs or not. Furthermore, paired t-test was used to compare the volume between HBL and mHBL.

RESULTS

The mean age and duration of RA was 65.2 ± 9.3 years and 14.3 ± 10.7 years, respectively. There were 13 grade I cases, 34 grade II cases, and 14 grade III cases as assessed by Steinbrocker classification and the most common anti-RA drugs were DMARDs (57.4%). The mean intraoperative bleeding, drainage, and blood loss in drainage (DBL) was 453.3 ± 377.8 mL, 489.1 ± 253.8 mL, and 304.6 ± 156.3 mL, respectively. There was no difference on HBL and mHBL in gender. HBL and mHBL was larger in patients over 60 years (P = 0.040 and P = 0.023). There were differences in intraoperative blood loss, drainage, and DBL based on different number of segments but not in HBL and mHBL, or on Steinbrocker classification. DBL was lower in DMARDs group than non-drugged group (P = 0.03), while HBL and mHBL were both of no significance. The comparison of HBL and mHBL showed statistical difference (P < 0.001), suggesting that mHBL volume is larger than HBL.

CONCLUSIONS

Patients diagnosed as LSS with RA have amounts of HBL or mHBL after PLIF. HBL or mHBL is not associated with RA activity, which may not increase in RA patients compared with common ones. Taking DMARDs may reduce postoperative DBL. The fact that mHBL is larger than HBL provides an all-round basis for measuring factual HBL.

Development and validation of a nomogram for prediction of the risk of positive hidden blood loss in the perioperative period of single-level thoracolumbar burst fracture

BACKGROUND

This study aimed to develop and validate an individualized nomogram to predict the risk of positive hidden blood loss (HBL) in patients with single-level thoracolumbar burst fracture (TBF) during the perioperative period.

METHODS

We conducted a retrospective investigation including 150 consecutive patients with TBL, and the corresponding patient data was extracted from March 2013 to March 2019. The independent risk factors for positive HBL were screened using univariate and multivariate logistic regression analyses. According to published literature and clinical experience, a series of variables were selected to develop a nomogram prediction model for positive HBL. The area under the receiver operating characteristic curves (AUC), C-index, calibration plot, and decision curve analysis (DCA) were used to evaluate the performance of the prediction model. Bootstrapping validation was performed to evaluate the performance of the model.

RESULTS

Among the 150 consecutive patients, 62 patients were positive for HBL (38.0%). The multivariate logistic regression analysis showed that the six risk factors of age, length of surgical incision, duration of operation, percentage of vertebral height restoration (P1%), preoperative total cholesterol, and preoperative fibrinogen were independent risk factors of positive HBL. The C-index was 0.831 (95% CI 0.740-0.889) and 0.845 in bootstrapping validation, respectively. The calibration curve showed that the predicted probability of the model was consistent with the actual probability. Decision curve analysis (DCA) showed that the nomogram had clinical utility.

CONCLUSION

Overall, we explored the relationship between the positive HBL requirement and predictors. The individualized prediction model for patients with single-level TBF can accurately assess the risk of positive HBL and facilitate clinical decision making. However, external validation will be needed in the future.

Perioperative Hidden Blood Loss in Elderly Cervical Spondylosis Patients With Anterior Cervical Discectomy Fusion and Influencing Factors

Introduction:

To analyze the perioperative hidden blood loss (HBL) and its influencing factors in elderly cervical spondylosis patients treated with anterior cervical discectomy fusion (ACDF).

Materials and Methods:

From January 2017 to December 2018, 128 elderly cervical spondylosis patients (age > 65 y) treated with ACDF were selected. The patients’ height, weight, duration of symptoms, previous medical history and other basic information were routinely recorded. The hemoglobin (Hb), hematocrit (Hct) and blood coagulation function preoperative and the next day postoperative were recorded. The operation time, surgical bleeding, ASA classification, fixation method, total drainage and the time for extraction of drainage tube were recorded. The total blood loss (TBL) was calculated according to the Gross’s formula, and HBL was calculated based on TBL, total drainage and surgical bleeding. The statistical analysis of HBL was performed, and then influential factors were further analyzed by multivariate linear regression analysis and t test.

Results:

The mean surgical bleeding was 102.70 ± 46.78 mL and HBL was 487.98 ± 255.96 mL. HBL accounted for 67.61 ± 5.20% of TBL. According to the multiple linear regression analysis, the gender (P = 0.047), operation time (P = 0.000), fixation method (P = 0.014) and international normalized ratio (INR) (P = 0.003) influenced the amount of HBL. Body mass index (BMI) (P = 0.624), hypertension (P = 0.977), diabetes (P = 0.528), blood type (P = 0.577), ASA classification (P = 0.711), duration of symptoms (P = 0.661), preoperative cobb angle (P = 0.152), number of surgical level (P = 0.709), intramedullary hyperintensity (P = 0.967), drainage time (P = 0.294), postoperative drainage volume (P = 0.599), prothrombin time (PT) (P = 0.674), activated partial thromboplastin time (APTT) (P = 0.544) and thrombin time (TT) (P = 0.680) had no correlation with the amount of HBL.

Conclusions:

There was obvious HBL during the perioperative period of ACDF in elderly cervical spondylosis patients. The male patients, longer operation time, fusion with titanium plate and cage and high INR were independent risk factors for HBL.

Perioperative Hidden Blood Loss in Elderly Osteoporotic Vertebral Compression Fracture Patients With Percutaneous Vertebroplasty and Influencing Factors

Introduction

To analyze perioperative hidden blood loss (HBL) and its influencing factors in elderly patients with osteoporotic vertebral compression fracture (OVCF) treated with percutaneous vertebroplasty (PVP).

Materials and Methods

From January 2016 to December 2018, 103 elderly patients with OVCF (age > 85 years) treated with PVP were selected. The patient's height, weight, duration of symptoms, previous medical history and other basic information were recorded. The hemoglobin (Hb) and hematocrit (Hct) immediately after admission and the next day postoperative were recorded. The operation time, surgical bleeding, Kummell's disease, vertebral height preoperative and postoperative, and bone cement leakage was recorded. The total blood loss (TBL) was calculated according to Gross's formula, and HBL was calculated based on the TBL and surgical bleeding. The influential factors were analyzed by multivariate linear regression analysis and single factor correlation analysis.

Results

The mean surgical bleeding was 11.83 ± 5.37 mL, and HBL was 306.19 ± 185.92 mL, with a statistically significant difference (P = 0.000). According to the multiple linear regression analysis, the duration of symptoms (P = 0.030), number of fracture segments (P = 0.016), operation time (P = 0.004), loss of vertebral height (P = 0.026), recovery of vertebral height (P = 0.004), Kummell's disease (P = 0.040) and cement leakage (P = 0.004) were correlated with an increased amount of HBL. Sex (P = 0.077), body mass index (BMI) (P = 0.486), hypertension (P = 0.734), diabetes (P = 0.769), fracture level (P = 0.518) and surgical bleeding (P = 0.821) had no correlation with the amount of HBL.

Conclusions

There was obvious HBL during the perioperative period of PVP in elderly patients with OVCF. A fresh fracture, multi-segment vertebral fracture, longer operation time, presence of Kummell's disease, loss of vertebral height, recovery of vertebral height and cement leakage the increased perioperative HBL during PVP.

The influence of topical use of tranexamic acid in reducing blood loss on early operation for thoracolumbar burst fracture: a randomized double-blinded controlled study

Purpose

To investigate the safety and efficacy of topical use of tranexamic acid (TXA) on early operation for thoracolumbar burst fracture (TBF).

Methods

Patients with acute TBF requiring early decompression were prospectively collected. The enrolled patients were randomly assigned to TXA and control group, in which wound surface was soaked with TXA or the same volume of normal saline for 5 min after wound incision, respectively. The total blood loss (TBL), intraoperative blood loss (IBL), postoperative blood loss (PBL), hemoglobin (HGB) levels on preoperatively (pre-op) and postoperatively, and amount of allogenic blood transfusion were recorded. Furthermore, the general information was also compared between groups.

Results

There were 39 and 37 patients enrolled in TXA and control group for final analysis. The demographics data showed no significant difference between groups (P > 0.05), but operation time and IBL were significantly decreased in TXA group (P < 0.05). Further analysis showed that HGB level was significantly higher in the TXA group at POD1, while the TBL and PBL were significantly less than those in the control group (P < 0.05), but similar to HBL (P > 0.05). The postoperative ambulation time, removal time of drainage tube, length of hospital stay, and blood transfusion rate were also significantly less in TXA group (P < 0.05). At the final follow-up, no neurological deteriorations and no TXA-related complications were observed in both groups.

Conclusion

This RCT first demonstrated that topical TXA usage after wound incision could effectively reduce IBL without increasing risk of complications, beneficial to enhanced recovery after early operation for TBF.

Electronic supplementary material

The online version of this article (10.1007/s00586-020-06626-x) contains supplementary material, which is available to authorized users.

Postoperative Blood Loss Including Hidden Blood Loss in Early and Late Surgery Using Percutaneous Pedicle Screws for Traumatic Thoracolumbar Fracture

Introduction

Some reports revealed that hidden blood loss (HBL) during surgery for traumatic thoracolumbar fracture cannot be ignored, even when using a percutaneous approach. Using percutaneous pedicle screws (PPS) for traumatic thoracolumbar fracture, this study aimed to compare estimate blood loss (EBL), including HBL, between early and late fixation.

Methods

This investigation was a retrospective study. In the present study, data from 39 patients who underwent posterior spinal stabilization using PPS for single-level thoracolumbar fracture have been included. We divided the patients into an early group (group E) (n=20) in whom surgery was conducted within 3 days of fracture and a late group (group L) (n=19) in whom surgery was conducted more than 3 days after fracture. We evaluated hemoglobin (Hb) on the day of injury, and 1, 3 or 4, and 7 days after surgery, EBL, HBL, and transfusion requirement.

Results

Hb on day 1 (group E: 12.2±1.7 g/dL, group L: 12.3±1.6 g/dL) was significantly less than that on the injured day (group E: 14.2±1.7 g/dL, group L: 13.9±1.7 g/dL) in both groups. The values of Hb and EBL were not significantly different at any time between the two groups. HBL (group E: 487±266 mL, group L: 386±305 mL) was not significantly different between the two groups. No patients required transfusion in either group.

Conclusions

EBL in early fixation using PPS for traumatic thoracolumbar fracture is not significantly different compared with that in late surgery from days 1 to 7 postoperatively. Early fixation using PPS for traumatic thoracolumbar fracture does not result in negative outcomes any more than those in late surgery in terms of blood loss.

Hidden blood loss and its possible risk factors in minimally invasive transforaminal lumbar interbody fusion

Background

With respect to spinal surgeries, elucidating absolute and relative amount of hidden blood loss (HBL) is of great importance in order to avoid aforementioned potential complications. To evaluate HBL and its possible risk factors among patients undergoing minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) for lumbar degenerative diseases.

Methods

Between June 2018 and March 2019, 137 consecutive patients with lumbar degenerative disease, who underwent operation with MIS-TLIF technique, were enrolled in this study. The patient’s demographic characteristics and blood loss-related parameters were collected, respectively. The Pearson or Spearman correlation analysis was used to investigate an association between patient’s characteristics and HBL. Multivariate linear regression analysis was used to confirm independent risk factors of HBL.

Results

A total of 137 patients (86 males and 51 females, age range 19–78 years) were reviewed in our hospital. A substantial amount of HBL (488.4 ± 294.0 ml, 52.5% of TBL) occurred after MIS-TLIF. Multivariate linear regression showed that the age, muscle thickness, the Patients’ Society of Anesthesiologists (ASA) classification, patient’s blood volume (PBV), total blood loss (TBL), postoperative (i.e., day 2 or 3) hematocrit (Hct), Hct loss, and fibrinogen level were independent risk factors for HBL (P1 = 0.000, P2 = 0.002, P3 = 0.006, P4 = 0.002, P5 = 0.003, P6 = 0.048, P7 = 0.004, P8 = 0.000).

Conclusion

A large amount of HBL was incurred in patients undergoing MIS-TLIF. More importantly, the age, muscle thickness, ASA classification, PBV, TBL, postoperative Hct, Hct loss, and fibrinogen level were independent risk factors for HBL in MIS-TLIF. HBL and its risk factors should be paid more attention to during the perioperative period.

Posterior Vertebrectomy via the Unilateral Pedicle or Bilateral Pedicle Approach in the Treatment of Lumber Burst Fracture with Neurological Deficits: A Comparative Retrospective Cohort Study

BACKGROUND Posterior vertebrectomy with bilateral pedicle approach (BPA) is widely applied in lumber burst fracture (LBF). However, some disadvantages exist, such as a prolonged operation time, extensive soft tissue injury, and excessive blood loss. Posterior vertebrectomy with unilateral pedicle approach (UPA) is a novel technique for decompression of spinal canal. Thus, we explored the potential of UPA to achieve better outcomes than BPA. MATERIAL AND METHODS Of 47 patients who underwent posterior vertebrectomy for LBF, 23 patients were treated with UPA and 24 patients were treated with BPA. Clinical and radiographical outcomes were assessed with a follow-up of more than 24 months. Patients were evaluated before and after surgery according to the following parameter: duration of operation (DO), blood loss volume (BLV), the kyphotic angle (KA), the ratio of the height of anterior vertebral edge, the ratio of the sagittal injury, visual analog scale (VAS), Oswestry Disability Index (ODI), and Frankel scores. RESULTS The follow-up time ranged from 24 to 37 months (average 26.4 months). The UPA group had significantly decreased DO and BLV (P<0.05). The 2 cohorts showed similar performance at 6 months (P>0.05), 12 months (P>0.05), and 24 months (P>0.05) post-surgery, in terms of parameters including KA, the ratio of the vertebral anterior, the ratio of sagittal damage, Frankel scores, ODI, and VAS. CONCLUSIONS UPA and BPA had a similar clinical performance for LBF. However, the shorter DO and lower BLV achieved in the UPA cohort suggested UPA is a better alternative for LBF.