Hidden blood loss in anterior lumbar interbody fusion (ALIF) surgery

Lumbar Fusions in Patients with Sickle Cell Disease: A Propensity-Matched Analysis of Postoperative Complications

OBJECTIVE

The present study compares postoperative outcomes between patients with and without sickle cell disease (SCD) undergoing 1-to 3-level lumbar spinal fusion for degenerative pathologies.

METHODS

Patients who underwent 1-to 3-level lumbar spinal fusion for degenerative pathologies from 2010 to 2021 were identified using the PearlDiver database. Patients were separated into 1) SCD and 2) non-SCD groups and were propensity-matched 1:1 for age, sex, Elixhauser Comorbidity Index, surgical approach, and various comorbidities. Complications were separately analyzed by single- and multilevel procedures using chi-squared and Mann-Whitney U testing.

RESULTS

Propensity-score matching identified 1934 SCD and non-SCD patients who underwent single-level fusion and 2094 SCD and non-SCD patients who underwent multilevel fusion. Across single-level fusions, those with SCD had a significantly higher risk of neurovascular compromise (P < 0.001), venous thromboembolism (P = 0.004), pneumonia (P = 0.032), urinary tract infections (P = 0.001), and greater postoperative opioid usage out to 12 months (P = 0.018). Across multilevel fusions, SCD carried higher risk for neurovascular compromise (P < 0.001), pneumonia (P = 0.010), and urinary tract infections (P < 0.001). All SCD patients had significantly higher opioid use at 1 month (P = 0.001) and at 6 months (P = 0.009) postoperatively.

CONCLUSIONS

Patients with SCD undergoing lumbar spinal fusion demonstrate higher risks for coagulopathic, ischemic, and infectious-related complications, as well as long-term postoperative opioid use. Awareness of the unique complication profile in SCD patients may help guide surgeons in refining perioperative management strategies to optimize outcomes in patients with SCD.

Prognostic Factors for Outcome of Fusion Surgery in Patients With Chronic Low Back Pain - A Systematic Review

STUDY DESIGN

Systematic review.

OBJECTIVE

This systematic review aims to identify prognostic factors, encompassing biomedical and psychosocial variables, linked to outcome of fusion surgery for chronic low back pain (CLBP) in single or two-level lumbar degenerative spinal disorders. Identifying these factors is crucial for decision making and therefore long-term treatment outcome.

METHODS

A systematic search (PROSPERO ID: CRD4202018927) from January 2010 to October 2022 was conducted, utilizing Medline, Embase, and the Cochrane Database of Systematic Reviews (CDSR, CENTRAL). Prognostic factors associated with various outcomes, including functional status, back and leg pain, health-related quality of life, complications, return to work, and analgesic use, were assessed. Risk of bias was determined using QUIPS, and the quality of evidence was evaluated using GRADE approach.

RESULTS

Of the 9852 initially screened studies, eleven studies (n = 16,482) were included in the analysis. In total, 161 associations were identified, with 67 prognostic factors showing statistical significance (P < 0.05). Thirty associations were supported by two or more studies, and only eight associations were eligible for meta-analyses: female gender remained statistically significant associated with decreased postoperative back pain, but negatively associated with complication rates and functional status, and smoking with increased postoperative back pain.

CONCLUSION

Only female gender and smoking were consistently associated with outcome of fusion for CLBP. Most of the included studies exhibited low to moderate methodological quality, which may explain the relatively weak associations identified for the assessed prognostic factors.

Effect of Tranexamic Acid on Hidden Blood Loss in Percutaneous Endoscopic Transforaminal Lumbar Interbody Fusion: A Retrospective Study

Purpose

Percutaneous endoscopic transforaminal lumbar interbody fusion (PE-TLIF) has become one of the most popular minimally invasive surgeries today. However, the issue of hidden blood loss (HBL) in this surgery has received little attention. This study aims to examine the HBL in PE-TLIF surgery and the effect of tranexamic acid (TXA) on blood loss.

Methods

In our research, We conducted a retrospective analysis of 300 patients who underwent PE-TLIF from September 2019 to August 2023. They were divided into 2 groups based on whether they received intravenous TXA injection before surgery. The variables compared included: demographic data, pre-and postoperative hemoglobin (HB), hematocrit (HCT), platelets (PLT), red blood cells (RBC), total blood loss (TBL), visible blood loss (VBL), HBL, operation time, postoperative hospital stay, inflammatory markers, coagulation parameters, and adverse events.

Results

Regarding demographic characteristics, besides the operation time, no significant differences were observed between the two groups. Compared with the control group, the TXA group showed a significant reduction trend in TBL, HBL, and VBL (P < 0.05). On the first day after surgery, there were significant differences in prothrombin (PT), activated partial thromboplastin time (APTT), and D-dimer (D-D) levels between the two groups. Similarly, HCT also found similar results on the third day after surgery. No adverse events occurred in either group.

Conclusion

Research has found that there is a significant amount of HBL in patients undergoing PE-TLIF. Intravenous injection of TXA can safely and effectively reduce perioperative HBL and VBL. Additionally, compared to the control group, the TXA group shows a significant reduction in operation time.

Hidden Blood Loss and Its Risk Factors for Oblique Lumbar Interbody Fusion

(1) Background: The amount of blood loss during oblique lumber interbody fusion (OLIF) surgery is often underestimated and may contribute to adverse postoperative outcomes. This study aims to evaluate hidden blood loss (HBL) in patients who underwent OLIF for degenerative lumbar spine disease and to analyze its risk factors. (2) Methods: The medical records of 179 patients who underwent OLIF surgery from 2015 to 2022 were reviewed. The HBL and total blood loss (TBL) were estimated using the Gross formula. Pearson correlation, Spearman correlation, and multivariate linear regression analyses were used to investigate risk factors for HBL. (3) Results: The mean HBL was 675.2 mL, and the mean hemoglobin loss was 1.7 g/dL during OLIF surgery. In the multivariate linear regression analysis, TBL (p < 0.001), estimated blood loss (p < 0.001), and pedicle screw fixation type (p = 0.039) were identified as independent risk factors of HBL. (4) Conclusions: The OLIF is associated with substantial perioperative HBL, for which we identified risk factors of TBL, EBL, and pedicle screw fixation type. Notably, OLIF with percutaneous pedicle screw fixation resulted in greater HBL than stand-alone OLIF or OLIF with open pedicle screw fixation.

"Early Efficacy and Safety of Unilateral Biportal Endoscopic Lumbar Interbody Fusion Versus Minimal Invasive in the Treatment of Lumbar Degenerative Diseases"

STUDY DESIGN

This was a retrospective cohort study.

OBJECTIVE

To compare the early clinical efficacy and radiologic outcomes between unilateral biportal endoscopic lumbar interbody fusion (ULIF) and minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF).

SUMMARY OF BACKGROUND DATA

Along with the continuous development of endoscopic technology, the early safety and effectiveness of ULIF technology are still unknown.

MATERIALS AND METHODS

This retrospective study included 61 patients who underwent fusion surgery through ULIF or MIS-TLIF in 2021. Twenty-nine patients underwent ULIF (group A), and 32 underwent MIS-TLIF (group B). Fusion rate, bone graft volume, hidden blood loss (HBL), C-reactive protein level, operative time, Oswestry Disability Index , Visual Analog Scale score, and MacNab criteria were assessed in both groups.

RESULTS

The Visual Analog Scale score for back pain in the early postoperative period was significantly lower in group A than in group B ( P <0.05). All other clinical scores showed improvement, with no significant difference between the 2 groups ( P >0.05). There was no statistically significant difference in postoperative C-reactive protein levels and fusion rates between the 2 groups ( P >0.05). However, HBL was higher and operative time was longer in group A than in group B ( P <0.05). Most importantly, there were no statistically significant differences between groups A and B in fusion rate, length of stay and bone graft volume ( P >0.05). No serious surgical complications occurred in our study.

CONCLUSIONS

ULIF is a new option for lumbar fusion. Despite the drawbacks of longer operation time and higher HBL, ULIF may be a viable alternative to MIS-TLIF as technology advances.

Comparison of surgical invasiveness, hidden blood loss, and clinical outcome between unilateral biportal endoscopic and minimally invasive transforaminal lumbar interbody fusion for lumbar degenerative disease: a retrospective cohort study

BACKGROUND

Currently, hidden blood loss (HBL) has been paid more and more attention by spine surgeons. Simultaneously, it has been the effort of spine surgeons to explore more advantages of minimally invasive surgery. More and more articles have compared unilateral biportal endoscopic lumbar interbody fusion (BE-LIF) and minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF). But so far, there is no HBL comparison between BE-LIF and MIS-TLIF. This study aims to compare the surgical invasiveness, hidden blood loss, and clinical outcome of BE-LIF and MIS-TLIF and to provide insight regarding minimally invasive surgery for lumbar degenerative disease (LDD).

METHODS

We enrolled 103 eligible patients with LDD who underwent BE-LIF (n = 46) and MIS-TLIF (n = 57) during August 2020-March 2021. We collected data, including demographics, perioperative haematocrit, operative and postoperative hospital times, serum creatine kinase (CK) and C-reactive protein (CRP) levels, and hospitalization costs. Total and hidden blood loss was calculated. Clinical outcomes were assessed using a visual analogue scale (VAS) score for back and leg pain, Oswestry Disability Index (ODI), modified MacNab criteria, fusion rate, and complications.

RESULTS

Basic demographics and surgical data were comparable. The CRP and CK levels were generally lower in the BE-LIF than in the MIS-TLIF group, especially CRP levels on postoperative day (POD) three and CK levels on POD one. True total blood loss, postoperative blood loss, and hidden blood loss were significantly reduced in the BE-LIF group compared with the MIS-TLIF group. Postoperative hospital times was statistically significantly shorter in the BE-LIF group. The VAS pain and ODI scores improved in both groups. At three days and one month, the VAS lower back pain scores were significantly better after BE-LIF. Clinical outcomes did not otherwise differ between groups.

CONCLUSIONS

Compared with MIS-TLIF, BE-LIF has similar medium and short-term clinical outcomes. However, it is better regarding surgical trauma, early lower back pain, total and hidden blood loss, and recovery time. BE-LIF is an adequate option for selected LDD.

Blood loss in laparoscopic distal pancreatectomy could be underestimated

BACKGROUND

Previous studies have reported that laparoscopic distal pancreatectomy (LDP) has an advantage in reducing blood loss over open distal pancreatectomy (ODP). This study was performed to investigate whether blood loss is truly reduced in LDP.

METHODS

A total of 113 patients undergoing DP from 2014 to 2022 were classified into Open and LDP groups and compared by statistical analysis. Estimated blood loss (EBL) was calculated from the perioperative changes in the hematocrit, hemoglobin, or red blood cell volume, and actual blood loss (ABL) was taken from the operative record.

RESULTS

ABL was significantly lower in the LDP than ODP group (50[5-1350] vs 335 [5-1950] ml, P < .01). However, there were no significant differences in EBL calculated from the hematocrit (406 [66-1990] vs 540 [23-1490] ml, P = .14), hemoglobin, or red blood cell volume. EBL showed more linear correlations with ABL in the ODP group (r = 0.64-0.73) than in the LDP group (r = 0.52-0.57). In the multivariate analysis for ABL, ODP (P = .02) and operative time (P < .01) were significant factors. In contrast, no significant factors were found for EBL.

CONCLUSIONS

Intraoperative blood loss may be underestimated in LDP, and a new evaluation method needs to be established.

Hidden blood loss of minimally invasive hybrid lumbar interbody fusion: an analysis of influencing factors

BACKGROUND

Lumbar interbody fusion(LIF) is the leading way to treat Lumbar Degenerative Diseases(LDD). At present, there is a lack of research on the influencing factors of hidden blood loss in minimally invasive hybrid lumbar interbody fusion. This study comprehensively explores the definite factors affecting the hidden blood loss in minimally invasive hybrid lumbar interbody fusion.

MATERIALS AND METHODS

One hundred patients with Lumbar degenerative diseases who underwent minimally invasive hybrid lumbar interbody fusion in our center were included. Demographics, laboratory data, surgical data, and radiographic data were collected. The Gross equation and Sehat equation were used to calculate the estimated value of hidden blood loss. Multi-factor linear regression analysis was used to determine the influencing factors of hidden blood loss.

RESULT

We reviewed and collected 100 patients who underwent minimally invasive hybrid approach, mean age 65 ± 10 years, male: female 37:63; 17 patients of diabetes and 83 patients of non-diabetes; Total blood loss was 645.59 ± 376.37 ml, hidden blood loss was 421.39 ± 337.45 ml, the hidden blood loss percentage was 57 ± 26%. Results from the multi-factorial linear regression model: Diabetes (p < 0.05), hypertension (p < 0.05), psoas thickness (p < 0.05) and dorsal extensor group thickness (p < 0.05) were potential risk factors for postoperative hidden blood loss.

CONCLUSION

Although minimally invasive hybrid approach is minimally invasive surgery, there is still a significant amount of hidden blood loss. There is a greater risk of blood loss in diabetes, hypertension and preoperative MRI assessment of thickness of the psoas, thickness of the dorsal extensor group.

Hidden blood loss and its influencing factors after minimally invasive percutaneous transpedicular screw fixation in thoracolumbar fracture

Background

Minimally invasive percutaneous transpedicular screw fixation (MIPTSF) is generally accepted as a minimally invasive treatment for thoracolumbar fracture. However, hidden blood loss (HBL) caused by this procedure is usually disregarded. This study aimed to investigate the amount of HBL and its influencing factors after MIPTSF in thoracolumbar fracture.

Methods

Between October 2017 and December 2020, a total of 146 patients (106 males and 40 females, age range 21–59 years) were retrospectively examined, and their clinical and radiological data were recorded and analyzed. The Pearson or Spearman correlation analysis was used to investigate an association between patient’s characteristics and HBL. Multivariate linear regression analysis was performed to elucidate the related clinical or radiological factors of HBL.

Results

A substantial amount of HBL (164.00 ± 112.02 ml, 40.65% of total blood loss (TBL)) occurred after transpedicular screw internal fixation. Multivariate linear regression analysis revealed that HBL was positively associated with TBL (p < .001), percentage of vertebral height loss (VHL) (p < .001), percentage of vertebral height restoration (VHR) (p < .001), numbers of fractured vertebrae (P = .013), and numbers of fixed vertebral segments (P = .002).

Conclusion

A large amount of HBL was incurred in patients undergoing MIPTSF in thoracolumbar fracture. More importantly, TBL, percentage of VHL, percentage of VHR, the numbers of fractured vertebrae and fixed vertebral segments were independent risk factors for HBL.

Hidden blood loss in adolescent idiopathic scoliosis surgery

INTRODUCTION

Posterior spinal fusions (PSF) for adolescent idiopathic scoliosis (AIS) have higher blood loss than other pediatric orthopedic surgeries. There is a paucity of literature estimating the hidden blood loss (HBL) in patients with AIS undergoing PSF. The purpose of this study was to compare intraoperative and postoperative estimated blood loss (EBL) in patients undergoing PSF for AIS to determine HBL.

HYPOTHESIS

With contemporary blood loss prevention strategies, HBL will be higher than intraoperative EBL.

MATERIAL AND METHODS

Over a 3-year period, 67 patients with preoperative and postoperative hemoglobin (Hgb) measurements undergoing PSF for AIS were evaluated. Intraoperative EBL was estimated using a volumetric method and recorded by a perfusionist managing a cell saver machine. Total perioperative EBL was estimated using the validated formula: EBL=weight (kg)×age sex factor×(preoperative Hgb - postoperative Hgb)/preoperative Hgb. HBL was calculated as the total perioperative EBL minus the intraoperative EBL.

RESULTS

Calculated total EBL was higher than intraoperative EBL (771±256mL vs. 110±115mL, p<0.001). Mean HBL after wound closure was 660±400mL. Patients 14 years or greater (p=0.03), with a BMI≥25kg/m²(p=0.02) and with surgical times over 3.5hours (p=0.05) had increased HBL. Multivariate analysis determined BMI≥25kg/m² (OR 9.91; CI, 1.01-104.26; p=0.05) was associated with increased HBL. Allogenic blood transfusion was rare (4%) and associated with increased HBL (897±112mL vs. 540±402mL, p=0.05).

DISCUSSION

For patients undergoing PSF for AIS there is more HBL after wound closure than intraoperative blood loss. This HBL is higher in older patients who undergo longer operations and have a BMI≥25kg/m².

LEVEL OF EVIDENCE

IV; retrospective cohort study.

Quantification and influencing factors of perioperative hidden blood loss in patients undergoing laparoscopic ovarian cystectomy for benign ovarian tumours

This retrospective, monocentric study quantified hidden blood loss (HBL) and investigated its influencing factors in benign ovarian tumour patients undergoing laparoscopic ovarian cystectomy. Data from 153 patients who underwent laparoscopic ovarian cystectomy were retrospectively reviewed. HBL was calculated using the formula derived from 'Nadler' and 'Cross'. Pearson correlation was carried out to measure the association between HBL and potential risk factors. The average HBL was 280.22 ± 168.42 mL, accounting for 84.13 ± 19.20% of total blood loss (TBL) (347.48 ± 179.05 mL), which was a change of almost fourteen-fold relative to median visible blood loss [20.00 mL (10.00 mL, 57.5 mL)]. Surgical time, number of excisional tumours and preoperative albumin values were risk factors for HBL. HBL represents a large proportion more than 80% of TBL in patients undergoing laparoscopic ovarian cystectomy. Collectively, HBL is helpful for estimating intraoperative blood loss and better guidance of haemostatic agents, which reduces postoperative complications and expedites postoperative recovery. Additionally, the estimation of HBL also contributes to the summary, reflection and improvement of surgical technique.IMPACT STATEMENTWhat is already known on this subject? There has been a growing number of surgical patients with perioperative anaemia, which appears to be inconsistent with measured levels of visible intraoperative blood loss and postoperative drainage. This substantial but easily underestimated blood loss is known as hidden blood loss. To date, no published articles have evaluated HBL and its related risk factors in benign ovarian tumour patients undergoing laparoscopic ovarian cystectomy.What the results of this study add? HBL accounts for a large amount of TBL in laparoscopy for benign ovarian tumours. Surgical time, number of excisional tumours and preoperative albumin values are risk factors for HBL.What the implications are of these findings for clinical practice and/or further research? The management of HBL is important for the administration of perioperative blooding loss. In this context, HBL can be applied to estimate intraoperative blood loss and be better guidance of haemostatic agents to reduce postoperative complications and hasten postoperative rehabilitation. Additionally, the estimation of HBL also contributes to the summary, reflection and improvement of surgical technique.

Comparison of hidden blood loss and clinical efficacy of percutaneous endoscopic transforaminal lumbar interbody fusion and minimally invasive transforaminal lumbar interbody fusion

Purpose

Hidden blood loss (HBL) is a growing area of interest for spinal surgeons. Simultaneously, spine surgeons’ pursuit of minimally invasive spine surgery has never ceased, as evidenced by the increasing number of articles comparing percutaneous endoscopic transforaminal lumbar interbody fusion (Endo-TLIF) and minimally invasive transforaminal lumbar interbody fusion (Mis-TLIF). However, there has been no comparison of HBL between Endo-TLIF and Mis-TLIF. This study aimed to compare HBL, visible blood loss (VBL), and total blood loss (TBL) following Endo-TLIF and Mis-TLIF and evaluate the clinical significance of these procedures.

Methods

Between October 2017 and October 2019, 370 patients underwent lumbar interbody fusion at our institution and were followed up for at least 24 months. Our study included 41 Endo-TLIF and 43 Mis-TLIF cases. We recorded each patient’s age, height, weight, and haematocrit and calculated the TBL, which was used to indirectly obtain the HBL. Additionally, we compared the clinical outcomes of these two groups, including visual analogue scores for the lumbar spine and leg (VAS-Back; VAS-Leg), Oswestry Disability Index (ODI), Japanese Orthopaedic Association (JOA) scores, disease type, operative segment, and intervertebral fusion and complication rates.

Results

Endo-TLIF had significantly lower HBL, VBL, and TBL values than Mis-TLIF (P < 0.05 for all). Although Endo-TLIF contained significantly less HBL than Mis-TLIF, the HBL to TBL ratio was statistically greater in Endo-TLIF (91%) than in Mis-TLIF (87%). Concerning clinical outcomes, VAS-Back, VAS-Leg, ODI, JOA, and Endo-TLIF demonstrated greater improvement rates than Mis-TLIF one week post-operatively. However, at the final follow-up, VAS-Back, VAS-Leg, ODI, and JOA scores all demonstrated a trend toward sustained improvement, with no statistically significant between-procedure difference. There were no statistically significant between-procedure differences in disease type, surgical segment, and complication or fusion rates.

Conclusion

Endo-TLIF significantly reduced HBL, VBL, and TBL compared to Mis-TLIF and improved short-term clinical outcomes; however, long-term clinical outcomes and fusion rates remained comparable between the two groups, as did the incidence of peri-operative complications.

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.

Anterior lumbar interbody fusion: single institutional review of complications and associated variables

BACKGROUND CONTEXT

As more patients undergo anterior lumbar interbody fusion (ALIF) procedures and more devices are created for that purpose, it is important to understand the complications that can arise and the variables that mitigate risk for major and minor complications.

PURPOSE

To assess complication rates after ALIF with or without posterior instrumentation and variables associated with increased likelihood of postoperative complications. We aim to provide this data as benchmarking to improve patient safety and surgical care.

STUDY DESIGN

A single-center retrospective cohort study.

PATIENT SAMPLE

All adult patients who underwent ALIF between 2017 and 2019 was performed OUTCOME MEASURES: Post-operative major and minor complications were evaluated.

METHODS

Complications were recorded and presented as percentages. Patient demographics, perioperative, and postoperative data were also collected and analyzed between patients who had no complications and those that had any complication. Subgroup analysis of surgical complications were performed by nonparametric Chi-square tests. Continuous variables were compared using Mann-Whitney U tests.

RESULTS

Ninty-five of three hundred sixty-two (26.2%) of patients experienced a minor or major complication. Among the most common complications found were surgical site infections (5.8%), neurological complications (4.1%), vascular complications (3.6%), and urinary tract infections (3.3%). Patients undergoing ALIF alone with post-operative complications had higher mean age, higher BMI, higher ASA status, and experienced higher estimated blood loss. Patients undergoing ALIF and posterior instrumentation with post-operative complications were more likely to have diabetes and had a higher ASA status. Patients with any complications from both groups had longer length of stay, discharge to a non-home setting and were more likely to be readmitted or return to the operating room.

CONCLUSION

Our study reveals variables associated with complications at our institution, including age of the patient, BMI, and ASA status leading to higher complications and greater LOS, higher readmission rates, and disposition to skilled facilities.

Adjunctive Topical Tranexamic Acid for Blood Salvage Does Not Reduce Postoperative Blood Loss Compared with Placebo in Patients Who Undergo Palliative Decompressive Spinal Metastasis Surgery: A Randomized Controlled Trial

STUDY DESIGN

Randomized controlled trial.

OBJECTIVE

To evaluate the efficacy of adjunctive topical tranexamic acid (tTXA) in reducing postoperative blood loss and packed red cell (PRC) transfusion in patients who underwent palliative decompressive spinal metastasis surgery for malignant epidural spinal cord compression.

SUMMARY OF BACKGROUND DATA

Palliative decompressive spinal metastasis surgery is associated with massive postoperative blood loss and increased transfusion rate. tTXA reduces blood loss in traumatic or degenerative spinal surgery; however, the role of topical TXA in decompressive spinal metastasis surgery remains controversial.

METHOD

A total of 65 patients who underwent palliative decompressive thoracolumbar spinal metastasis surgery were included in this study. In 33 patients, 1 g of tTXA (20 mL) was soaked in an absorbable gelatin sponge and placed lateral to the decompressive site. The remaining 32 patients in the control group received the same procedures with normal saline at the same volume, instead of TXA. All of the patients received standard 1 g intravenous TXA, just before initiating the operation. The primary outcome was postoperative blood loss, and the secondary outcomes were postoperative PRC transfusion and complications.

RESULTS

No differences were found in postoperative blood loss between tTXA and placebo group (P50 778 mL [IQR 347, 1,122 mL] versus P50 490 mL [IQR 295, 920 mL]; P = 0.238). The number of patients requiring postoperative PRC transfusion were quite similar in tTXA and placebo groups (PRC transfusion in 15 patients [45.45%] versus 16 patients [50%]; P = 0.585). No complications related to TXA and absorbable gelatin sponge were observed.

CONCLUSION

We do not recommend tTXA as an adjunctive treatment for patients undergoing decompressive spinal metastasis surgery since it does not provide additional benefit to prophylactic intravenous TXA in postoperative blood loss and transfusion rate.Level of Evidence: 2.

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.

Is there a variance in complication types associated with ALIF approaches? A systematic review

Purpose

Anterior lumbar interbody fusion (ALIF) is a well-established alternative to posterior-based interbody fusion techniques, with approach variations, such as retroperitoneal, transperitoneal, open, and laparoscopic well described. Variable rates of complications for each approach have been enumerated in the literature. The purpose of this study was to elucidate the comparative rates of complications across approach type.

Methods

A systematic review of search databases PubMed, Google Scholar, and OVID Medline was made to identify studies related to complication-associated ALIF. PRISMA guidelines were utilised for this review. Meta-analysis was used to compare intraoperative and postoperative complications with ALIF for each approach.

Results

A total of 4575 studies were identified, with 5728 patients across 31 studies included for review following application of inclusion and exclusion criteria. Meta-analysis demonstrated the transperitoneal approach resulted in higher rates of retrograde ejaculation (RE) (p < 0.001; CI = 0.05–0.21) and overall rates of complications (p = 0.05; CI = 0.00–0.23). Rates of RE were higher at the L5/S1 intervertebral level. Rates of vessel injury were not significantly higher in either approach method (p = 0.89; CI =  − 0.04–0.07). Rates of visceral injury did not appear to be related to approach method. Laparoscopic approaches resulted in shorter inpatient stays (p = 0.01).

Conclusion

Despite the transperitoneal approach being comparatively underpowered, its use appears to result in a significantly higher rate of intraoperative and postoperative complications, although confounders including use of bone morphogenetic protein (BMP) and spinal level should be considered. Laparoscopic approaches resulted in shorter hospital stays; however, its steep learning curve and longer operative time have deterred surgeons from its widespread adaptation.

Analysis of Hidden Blood Loss and its Risk Factors in Oblique Lateral Interbody Fusion Surgery

STUDY DESIGN

This was a retrospective study.

OBJECTIVE

The objective of this study was to evaluate the volume of hidden blood loss (HBL) and analyze its influential factors in single level oblique lateral interbody fusion (OLIF) surgery.

SUMMARY OF BACKGROUND DATA

OLIF is a minimally invasive spine surgery and is increasingly used to treat lumbar degenerative disk diseases. It is generally believed that there is less bleeding during OLIF. However, HBL during the perioperative period is commonly ignored.

MATERIALS AND METHODS

From January 2018 to December 2019, a total of 70 patients underwent single level OLIF surgery were retrospectively reviewed. The values of preoperative and postoperative hematocrit (Hct) were recorded to reckon HBL in accordance with Gross formula. The influential factors included sex, age, height, weight, body mass index, hypertension, diabetes mellitus, American Society of Anesthesiologists classification, disease etiology, surgery type, operative time, surgical corridor distance, psoas cross-sectional area, thickness of abdominal wall soft tissue, coagulation panel value, platelet count, values of Hct and hemoglobin, and intraoperative blood loss. Independent sample t test, Pearson correlation, Spearman correlation, and multivariate linear regression analysis were performed to investigate the risk factors related to HBL.

RESULTS

The average volume of HBL was 809 mL and the average hemoglobin loss was 27.1 g/L in OLIF procedure. Multiple linear regression analysis revealed that thickness of abdominal wall soft tissue was the independent risk factor for HBL (P=0.008). Whereas age (P=0.414), activated partial thromboplastin time (P=0.314), preoperative value of Hct (P=0.854), disease etiology (P=0.362), operative time (P=0.389), and intraoperative blood loss (P=0.912) were not statistically associated with HBL.

CONCLUSIONS

HBL was substantial and the average volume of HBL was 809 mL in single level OLIF surgery. The thickness of abdominal wall soft tissue was the risk factor of HBL. Accurate assessment of HBL can prevent perioperative complications and ensure patients' safety.

Retroperitoneal Fibrosis After Spinal Surgery: A Report of 2 Cases

CASE

Retroperitoneal fibrosis (RPF) is a rare chronic fibroinflammatory disorder with typically unknown etiology (i.e., idiopathic). However, several causes have been identified, including retroperitoneal injury or inflammation. In this study, we describe 2 patients who developed RPF complicated by hydroureteronephrosis after (combined) anterior lower interbody fusion (ALIF) and posterior spine fusion. We also reviewed 6 additional cases from the literature of suspected RPF development after spinal surgery. In these cumulative 8 cases, ALIF was the common denominator.

CONCLUSION

RPF may develop after ALIF and should be considered a potential longer term complication of this procedure.

Analysis of risk factors for perioperative hidden blood loss in unilateral biportal endoscopic spine surgery: a retrospective multicenter study

Background

Hidden blood loss (HBL) represents an important complication of unilateral biportal endoscopic (UBE) spine surgery. This study aimed to evaluate HBL and its possible risk factors among patients undergoing UBE surgery for lumbar degenerative diseases.

Methods

This multicentric retrospective study was conducted in 3 different medical centers between July 2020 and April 2021. Data of patients who underwent UBE surgery were extracted by electronic medical record system. The patient’s demographic characteristics and blood loss-related parameters were recorded. We calculated the amount of HBL and explored the association between patient’s characteristics and HBL using Pearson or Spearman correlation analysis. Multivariate linear regression analysis was conducted to identify independent risk factors of HBL.

Results

A total of 136 patients (55 females and 81 males, age range 43 to 74 years) were included in this study. A substantial amount of HBL (469.5 ± 195.3 ml, 57.6% of TBL, total blood loss) occurred following UBE surgery. Multiple linear regression analysis indicated that the risk factors of HBL were as follows: age (P = 0.000), number of fusion levels (P = 0.015), American Society of Anesthesiologists (ASA) classification (P = 0.046), surgery time (P = 0.017), patient’s blood volume (PBV, P = 0.026), total blood loss (TBL, P = 0.001), postoperative (i.e., day 2 or 3) hematocrit (Hct, P = 0.034), Hct loss (P = 0.005), and fibrinogen (P = 0.028).

Conclusions

A certain amount of HBL occurs in UBE surgery and cannot be ignored in daily clinical practice. The age, number of fusion levels, ASA classification, surgery time, PBV, TBL, postoperative Hct, Hct loss, and fibrinogen are independent risk factors for HBL.

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.

Analysis of risk factors for perioperative hidden blood loss in patients undergoing transforaminal lumbar interbody fusion

Objective

This study was performed to analyze the correlation between perioperative hidden blood loss (HBL) and the general condition of patients undergoing transforaminal lumbar interbody fusion (TLIF).

Methods

We retrospectively analyzed patients who underwent TLIF from July 2017 to July 2019 in our hospital. Sex, age, body mass index, underlying diseases, American Society of Anesthesiologists classification, coagulation function, preoperative and postoperative hemoglobin level and hematocrit, surgery time, fusion level, intraoperative blood loss, and drainage volume were recorded. Postoperative complications were also recorded. The amount of HBL was calculated, and its correlation with related variables was analyzed.

Results

The mean surgery time was 153.32 ± 54.86 minutes. The total perioperative blood loss was 789.22 ± 499.68 mL, including HBL of 315.69 ± 199.87 mL. Pearson correlation analysis showed statistically significant differences in HBL according to the body mass index, hypertension, fibrinogen, surgery time, and fusion level. Multiple linear regression analysis indicated that the surgery time and fusion level were independent risk factors for HBL.

Conclusions

A certain amount of HBL occurs in TLIF surgery and cannot be ignored in daily clinical work. The operation time and surgery level are independent risk factors for HBL.

Total and hidden blood loss between open posterior lumbar interbody fusion and transforaminal lumbar interbody fusion by Wiltse approach

The purpose of this study was to calculate and compare the volume of hidden blood loss (HBL) and perioperative blood loss between open posterior lumbar interbody fusion (PLIF) and transforaminal lumbar interbody fusion (TLIF) by Wiltse approach.We retrospectively analyzed 143 patients between March 2017 and December 2017, they were randomly divided into PLIF group and TLIF group. The following information were collected on admission: patient's age, gender, height, weight, body mass index (BMI), surgery levels, surgical time, duration time, disorder type, intraoperative bleeding, wound drainage, visual analog scale (VAS) scores, neurological complications, transfusion rate. Preoperative and postoperative hematocrit (Hct) were recorded in order to calculate total blood loss (TBL) according to Gross's formula. To calculate each patient's HBL, chi-square test and Student's t test were used to analyze data.Patients in PLIF had a mean TBL of 1144 ± 356 mL, and the mean HBL was 486 ± 203 mL, 43.9 ± 16.2% of the TBL. While patients in TLIF, the mean TBL was 952 ± 303 mL, and the mean HBL was 421 ± 178 mL, 44.7 ± 17.0% of the TBL. Hence, there was significant difference in TBL and HBL between 2 groups, respectively (P = .000, P = .044). However, there was no difference in the ratio of the HBL between 2 groups (P = .797).The volume of HBL is lower in open TLIF by Wiltse approach than that in PLIF, which may be a large proportion of TBL in posterior lumbar fusion surgery. Comprehensive understanding of HBL can contribute to keep patient safety and better to rehabilitation in perioperative.

Analysis of hidden blood loss and its influential factors in myomectomy

OBJECTIVE

This study was performed to quantify hidden blood loss (HBL) and explore its influential factors in myomectomy.

METHODS

Two hundred nine patients who underwent myomectomy by laparotomy or laparoscopy from 1 January 2017 to 31 December 2018 were analyzed. Each patient's estimated blood volume and total blood loss (TBL) were calculated by the Nadler formula and Gross formula, respectively. The HBL was calculated by subtracting the visible blood loss (VBL) from the TBL. A multivariate linear stepwise analysis was applied to identify the influential factors of HBL in myomectomy.

RESULTS

The mean perioperative VBL and estimated TBL during myomectomy were 137.81 ±104.43 and 492.24 ± 225.00 mL, respectively. The mean HBL was 354.39 ± 177.69 mL, which accounted for 71.52% ± 15.75% of the TBL and was two to three times higher than the VBL. The duration of surgery, number of removed leiomyomas, and location of removed leiomyomas were independent risk factors for HBL in myomectomy.

CONCLUSIONS

HBL accounted for a significant percentage of TBL in myomectomy. A full understanding of the HBL in perioperative blood management may improve patients' postoperative rehabilitation.

Hidden blood loss and the influencing factors after laparoscopic cholecystectomy

BACKGROUND

A small amount of bleeding usually occurs during laparoscopic cholecystectomy (LC), but the occurrence of perioperative hidden blood loss (HBL) is ignored. So our objective is to investigate the amount of HBL and find out the influential factors in LC.

METHODS

From January 2017 to May 2019, 139 patients scheduled for LC were enrolled in the study. The data of patients' sex, age, height, weight, body mass index (BMI), form of gallbladder bed, gallbladder status, hypertension, diabetes, liver cirrhosis, drainage volume and operation time were recorded. The patients' height, weight and preoperative and postoperative haematocrit and haemoglobin were recorded and applied to the Gross formula to determine the amount of blood loss. The data of sex, age, BMI, hypertension, diabetes, gallbladder status, liver cirrhosis and operation time were analysed by multivariate linear regression analysis. One-way analysis of variance was performed to find out the relative correlation between HBL and the type of gallbladder bed.

RESULTS

The HBL was 259.3 ± 188.5 mL. On the basis of multivariate linear regression analysis and analysis of variance, the gallbladder bed, hypertension and the operation time are influential factors of HBL in patients with LC. However, sex, age, BMI, gallbladder status, liver cirrhosis and diabetes are not significantly correlated with HBL.

CONCLUSIONS

HBL should not be overlooked during the perioperative period of LC, especially in patients with hypertension, gallbladder bed >50% gallbladder surface or operation time >60 min.

Blood Loss of Posterior Lumbar Interbody Fusion on Lumbar Stenosis in Patients With Rheumatoid Arthritis: A Case-Control Study

STUDY DESIGN

Case-control study.

OBJECTIVE

To compare intraoperative bleeding, drainage, and hidden blood loss (HBL) of posterior lumbar interbody fusion (PLIF) on lumbar spinal stenosis (LSS) in patients with rheumatoid arthritis (RA) and non-RA and identify the risk factors of HBL with RA.

SUMMARY OF BACKGROUND DATA

Exploration on PLIF on LSS and HBL has been reported before while the comparison on total blood loss (TBL), especially HBL of PLIF or PLF on LSS between patients with RA and without RA has not been studied.

METHODS

Sixty-one patients diagnosed LSS with RA (RA group) and 87 matched patients without RA (NRA group) were enrolled and demographic characteristics, RA-related parameters, operation and blood loss information were extracted. Intraoperative blood loss, drainage, and HBL were primary outcomes and secondary measures included operation time, hematocrit (Hct) and hemoglobin (Hb), the number of anemia and blood transfusion.

RESULTS

There was no statistical difference in total blood loss (TBL), intraoperative blood loss, and postoperative drainage while HBL and the proportion of HBL in TBL were lower in NRA group (P < 0.001 and P = 0.012, respectively). Stratified analysis based on the number of surgical levels suggested HBL and the proportion of HBL in NRA group was superior in long-segment surgery (>2 segments). The secondary outcomes showed the change of Hct was lower in NRA group (P = 0.021) but not the reduction of Hb. In addition, there was no significant difference in neoformative and grade-aggravated anemia, as well as the number of allogeneic blood transfusion and operation time showed Steinbroker classification, disease-modifying anti-rheumatic drugs (DMARDs), hange of Hb and allogeneic blood transfusion were risk factors for HBL with RA.

CONCLUSION

There was no difference in TBL, intraoperative bleeding, and operation time, but HBL were higher in RA patients particularly in long-segmental operation. Steinbroker classification, DMARDs, the change of Hb, and allogeneic blood transfusion were independent risk factors for HBL in RA patients.

LEVEL OF EVIDENCE

3.

Hidden blood loss and its possible risk factors in cervical open-door laminoplasty

Objectives

To evaluate hidden blood loss (HBL) and its possible risk factors among patients following expansive open-door laminoplasty (EOLP) for multilevel, cervical spondylotic myelopathy.

Methods

This was a retrospective analysis of data from patients over 18 years of age who underwent posterior cervical EOLP (from C3-C6) in our department from January 2017 to July 2018. HBL was calculated by deducting the observed perioperative blood loss from the calculated total blood loss (TBL) based on the fall in haematocrit level.

Results

45 patients (35 men and 10 women) were identified. Mean ± SD HBL was 337.2 ± 187.8 ml, which was 46.8% of the total perioperative blood loss (705.2 ± 269.6 ml). Twenty-three patients developed postoperative anaemia. Posterior cervical soft tissue was positively correlated with both TBL and hidden blood loss (HBL) and hypertension was positively correlated with TBL.

Conclusions

HBL following cervical EOLP was significant and should be recognised as a detrimental factor to patient safety during the perioperative period, especially in patients with thick posterior cervical soft tissue.

Possible underestimation of blood loss during laparoscopic hepatectomy

Background

Previous studies have documented potential advantages of laparoscopic hepatectomy in decreasing blood loss compared with open surgery. This study aimed to compare intraoperative blood loss estimated using four different methods in open versus laparoscopic hepatectomy.

Methods

Patients undergoing liver resection between 2014 and 2017 were evaluated prospectively, differentiating between the laparoscopic and open approach. Groups were compared using univariable and multivariable analyses. Intraoperative blood loss was estimated using three formulas based on the postoperative decreases in haematocrit, haemoglobin or red blood cell volume, and using the conventional method of the sum of suction fluid amounts and gauze weight. In addition, blood loss per hepatic transection area was calculated to compare groups.

Results

Some 125 patients who underwent hepatectomy were selected, including 56 open hepatectomies and 69 laparoscopic liver resections. Intraoperative blood loss per hepatic transection area estimated by the conventional method was significantly less in the laparoscopic than the open group (3·6 (range 0·2-50·0) versus 6·6 (1·2-82·5) ml/cm² respectively; P < 0·001). In contrast, there were no significant differences between groups in blood loss estimated based on the decrease in haematocrit (12·9 (0-65·2) versus 8·1 (0-123·7) ml/cm²; P = 0·818), haemoglobin or red blood cell volume. Blood loss estimation using three formulas showed significant linear correlations with the blood loss estimated by the conventional method in the open group (r _s = 0·758 to 0·762), but not in the laparoscopic group (r _s = -0·019 to 0·031).

Conclusion

The conventional method of calculating blood loss in laparoscopic hepatectomy can underestimate losses.

Gynecologists May Underestimate the Amount of Blood Loss during Total Laparoscopic Hysterectomy

Background

We considered the possibility of underestimation of the amount of bleeding during laparoscopic surgery, and we investigated comparing the amount of bleeding between laparoscopic surgery and open surgery by considering the concentration of hemoglobin before and after surgery as indicators.

Methods

The following procedures were included: A, surgery for ovarian tumor; B, myomectomy; and C, hysterectomy either by laparoscopic surgery or open surgery. Patients who underwent the above procedures in between January 1, 2010, and December 31, 2017, were enrolled. We identified 1749 cases (A: 90, B: 105, and C: 325 of open surgery and A: 667, B: 437, and C: 125 of laparoscopic surgery). We considered the sum as an estimation of blood loss during surgery and the change in the value of hemoglobin in laboratory testing one day before and after surgery.

Results

During laparoscopic surgery, the measurements of blood loss included the following: A: 59.8 ml; B: 168.6 ml; and C: 206.8 ml. During open surgery, measurements of blood loss included the following: A: 130.7 ml; B: 236.7 ml; and C; 280.9 ml. The reduction of hemoglobin after surgery compared with that before surgery was less in laparoscopic surgery than that in open surgery in A and B; however, this reduction was not significantly different in C.

Conclusion

Our results suggest that the estimation of the bleeding in A and B was appropriate; however, the estimation might be underestimated in C during laparoscopic surgery.

Hidden Blood Loss in Posterior Lumbar Fusion Surgery: An Analysis of Risk Factors

STUDY DESIGN

Descriptive study.

OBJECTIVES

This study aimed to evaluate the hidden blood loss (HBL) of patients who underwent lumbar fusion surgery for degenerative spine and to analyze its risk factors.

SUMMARY OF BACKGROUND DATA

When planning transfusion strategies, blood loss calculation is important. However, in clinical practice, spine surgeons usually ignore the possibility that a large amount of HBL may occur after lumbar fusion surgery.

MATERIALS AND METHODS

We studied the patients who underwent posterior lumbar fusion (PLF) surgery for degenerative spine from 2014 to 2015 in one institution. The patient's demographics, comorbid conditions, coagulation panel value, surgical time, number of levels fused, American Society of Anesthesiologists (ASA) classification, cell saver, preoperative hematocrit level, preoperative hemoglobin level, and postoperative complications were collected retrospectively. Pearson correlation analyses were used to find an association between patient characteristics and HBL. Multivariate linear analysis was used to determine independent risk factors of HBL.

RESULTS

We reviewed 169 consecutive patients who underwent PLF surgery for degenerative spine in one institution. The mean amount of HBL was 588 mL, which was 39% of the total blood loss. On the basis of the model of multiple linear regression analysis, the multilevel fusion (P=0.001), surgical time (P=0.034), and fibrinogen level (P=0.027) were independent risk factors that contributed to HBL, but age of 60 years or above (P=0.110), postoperative complications (P=0.278), and cell saver were not (P=0.739).

CONCLUSIONS

We conclude that a large amount of HBL may occur in patients who underwent PLF surgery for degenerative spine. In addition, significant hidden loss may have a correlation with postoperative mortality. Multilevel fused, surgical time, and fibrinogen level should be paid close attention when considering strategies of fluid infusion and blood transfusion.

Hidden blood loss and its influencing factors after percutaneous kyphoplasty surgery: A retrospective study

Percutaneous kyphoplasty (PKP) surgery is generally accepted as a minimally invasive treatment for osteoporotic vertebral compression fractures (OVCFs). However, hidden blood loss (HBL) caused by this procedure is usually disregarded. This study aimed to investigate the amount of HBL and its influencing factors after PKP surgery.A total of 160 patients were retrospectively examined from January 2014 to January 2016, and their clinical and radiological data were recorded and analyzed. Preoperative and postoperative hematocrit (Hct) and hemoglobin (Hb) levels were also documented. HBL was calculated using Gross formula. Different factors, including gender, age, bone mineral density (BMD), number of fracture levels, hypertension, diabetes mellitus, operative time, percentage of vertebral height loss, percentage of vertebral height restoration, and cement leakage, were examined. Multivariate linear regression analysis was performed to elucidate the related clinical or radiological factors of HBL.A total of 122 patients with 169 levels were eligible for inclusion in the study. The mean HBL was 279 ± 120 mL, and the postoperative Hb loss was 8.2 ± 3.9 g/L. Multivariate linear regression analysis revealed that HBL was positively associated with operative time (P = .000), percentage of vertebral height loss (P = .037), and percentage of vertebral height restoration (P = .000). By contrast, HBL was not associated with gender (P = .874), age (P = .148), BMD (P = .134), number of fracture levels (P = .079), hypertension (P = .259), diabetes mellitus (P = .495), and cement leakage (P = .975). The postoperative incidence of anemia significantly increased by 39.3% compared with that of the preoperative incidence (χ = 21.432, P = .000).For patients with OVCFs, the amount of HBL after PKP is much larger than that observed perioperatively. Operative time, percentage of vertebral height loss, and percentage of vertebral height restoration are influencing factors of HBL.

Hidden Blood Loss in Anterior Cervical Fusion Surgery: An Analysis of Risk Factors

STUDY DESIGN

A retrospective study.

OBJECTIVES

Anterior cervical fusion surgery is widely used procedure in cervical spondylosis. When considering the blood reinfusion strategies of cervical fusion surgery, the amount of blood loss is one of the key elements. We usually calculate the blood loss according to the surgical bleeding plus the postoperative drainage; however, this method ignores the possibility that there may be hidden blood loss (HBL).

METHODS

We performed a retrospective study to determine the risk factors for HBL in patients who underwent anterior cervical fusion surgery for degenerative spine from 2013 to 2016. The Pearson correlation, Spearman correlation, and multivariate liner analysis were used to find association between patient characteristics and HBL.

RESULTS

A total of 107 consecutive patients who underwent anterior cervical fusion surgery for degenerative spine in our hospital were reviewed. The amount of HBL was 261 mL, or 50% of the total blood loss. According to the model of multiple linear regression analysis, patient sex (P = 0.028) and American Society of Anesthesiologists physical status classification (P = 0.029) were independent risk factors contributing to HBL, but preoperative hematocrit was not (P = 0.741).

CONCLUSIONS

We concluded that sex and American Society of Anesthesiologists physical status classification were independent risk factors of HBL in anterior cervical fusion surgery. In addition, there was a high proportion of HBL in anterior cervical fusion. When considering the strategies of transfusion, we should pay attention to the risk factors for HBL.

Topical use of tranexamic acid can effectively decrease hidden blood loss during posterior lumbar spinal fusion surgery: A retrospective study

In spinal fusion surgery, total blood loss (TBL) is composed of visible blood loss from the surgical field and wound drainage, and hidden blood loss (HBL). Until now, no published studies exist reporting the effect of topical use of tranexamic acid (tTXA) on HBL in patients undergoing posterior lumbar spinal fusion surgery. This study aimed to explore the effect of tTXA on HBL during primary posterior lumbar spinal fusion surgery. Between September 2014 and September 2016, 100 adult patients (age > 18 years) with lumbar disc herniation or lumbar spinal stenosis undergoing primary posterior lumbar instrumented spinal fusions at 1 institution were divided into tTXA and control groups. The primary outcome was HBL. Secondary outcomes include TBL, intraoperative blood loss (IBL), postoperative blood loss (PBL), hemoglobin (HGB) levels on preoperative (Pre-op) and postoperatively (days 1-3, POD1, POD2, POD3, respectively), and amount of allogeneic blood transfusion. Complications occurring perioperatively until hospitalization discharge were also collected. In the tTXA group (n = 50 patients), wound surface was soaked with TXA (1 g in 100 mL saline solution) for 5 minutes before wound closure. For the control group (n = 50 patients), wound surface was soaked with the same volume of normal saline. There were no significant differences in demographics, surgical traits between the 2 groups. There were no significant differences in IBL or perioperative blood transfusion requirements between the 2 groups. However, in the tTXA group, TBL, PBL, and HBL were significantly lower than those in the control group (550 ± 268 vs 833 ± 298 mL, 53.5 ± 43.9 vs 136.7 ± 87.9 mL, 356.7 ± 254.8 vs 501.1 ± 216.9 mL, P < .001, respectively). HGB levels were significantly higher in the tTXA group (P < .001) on POD1 and had a slower decline on POD2 and POD3 than the control group. No complications associated with TXA were observed. From these data, we conclude that tTXA can effectively reduce HBL, without significant complications in adult patients undergoing posterior lumbar spinal fusion surgery.

Comparison of the Total and Hidden Blood Loss in Patients Undergoing Open and Minimally Invasive Transforaminal Lumbar Interbody Fusion

PURPOSE

This study examined the volume of hidden blood loss (HBL) and compared perioperative blood loss between minimally invasive transforaminal lumbar interbody fusion (MI-TLIF) and open transforaminal lumbar interbody fusion (O-TLIF).

METHODS

Forty-eight patients who were treated with MI-TLIF and 59 patients treated with O-TLIF were enrolled in this study. Patients' height, weight, and preoperative and postoperative hematocrit (Hct) were recorded and used to calculate total blood loss (TBL) according to the Gross formula. Each patient's HBL was calculated. The data were further analyzed by the Student t test and the χ² test.

RESULTS

The visible blood loss (VBL) was 186 ± 95 mL in the MI-TLIF; however, the HBL (423 ± 233 mL; 66.5 ± 16.1% of TBL) was twice the VBL. The VBL in the O-TLIF group was 471 ± 147 mL, and the HBL was 271 ± 223 mL (31.3 ± 23.9% of TBL). Although TBL in MI-TLIF (602 ± 251 mL) was less than in O-TLIF (742 ± 275 mL), the HBL was significantly higher (P < 0.01). No difference in postoperative blood loss was observed between the 2 groups. Seven and 10 patients had preoperative anemia in the MI-TLIF group and the O-TLIF group, respectively, and 32 and 45 postoperatively.

CONCLUSION

HBL is seriously underestimated and accounts for a large percentage of TBL in both MI-TLIF and O-TLIF. A correct understanding of HBL can ensure patient safety and improve postoperative rehabilitation.

The further exploration of hidden blood loss in posterior lumbar fusion surgery

PURPOSE

Hidden blood loss (HBL) plays an important role in lumbar fusion surgery. However, there was huge computation error when calculating hidden loss in previous studies because they regarded the volume of drainage as postoperative blood loss. We should not ignore the fact that the composition of drainage varies from person to person and also with time-lapse after operation. The purpose of this study was to demonstrate a more accurate HBL calculation formula by comparing it with previous formula and to address the importance of HBL in patients undergoing posterior lumbar fusion surgeries.

METHODS

For each patient, the HBL was calculated by previous formula and our recommendable formula. We compared the result of HBL calculated by two different methods. At the same time, we explored the HBL in patients undergoing posterior lumbar fusion surgeries with various levels.

RESULTS

In our study, the average total blood loss was 771ml. The mean intraoperative blood loss was 268ml, and the total volume of post-operative drainage is 276ml. The mean hidden loss of 90 patients calculated with previous method was 227ml and 29.4% of total loss. When taking change of drainage HCT into account, the mean hidden loss calculated with our recommendable method was 362.8ml and 47% of total loss. The results were significantly different (P<0.01). There was no significant difference in the percentage of the HBL between patients with single or multiple surgical levels.

CONCLUSIONS

There is often a substantial unmeasured blood loss in lumbar fusion surgeries. However, the component of drainage changed radically with time, we should take the true blood contained in drainage into considerations when calculating the HBL.

LEVEL OF EVIDENCE

Our research is a case-control study and the level of proof is III.