Hypoalbuminaemia in the perioperative period: clinical significance and management options

The combined risk predictive power of frailty and hypoalbuminemia in free tissue flap reconstruction: A cohort study of 34,571 patients from the NSQIP database

INTRODUCTION

Significant morbidity and mortality are hallmarks of the functional decline seen in physically frail patients. The modified frailty index 5 (mFI-5) represents a risk predictor score that has been validated as a comorbidity-based scale in surgery. Serum albumin levels of <3.5 g/dL (hypoalbuminemia) have also been implicated with poor postoperative outcomes. However, the association between these two parameters remains to be investigated. We aimed to elucidate the interdependence of preoperative albumin levels and frailty, as evaluated by the mFI-5 score, and its reliability to prognosticate postoperative results in free flap reconstruction (FFR).

METHODS

We conducted a multicenter, retrospective cohort study and accessed the ACS National Surgical Quality Improvement Program (ACS-NSQIP) from 2008 to 2021. We identified all adult patients (≥18 years of age) who underwent a FFR. We extracted perioperative data and lab values including albumin. Multivariable linear and logistic regression analyses were performed to identify independent risk predictors. Main outcomes involved mortality, length of hospital stay, reoperation, medical and surgical complications, and discharge destination within the 30-day postoperative period.

RESULTS

A total of 34,571 patients were included in the study, with an average age of 53.9 years (standard deviation [SD] 12.2) and an average body mass index (BMI) of 28.8 (SD 6.1). Of these patients, 7484 were male (21.6%), whereas 22,363 (64.7%) had no frailty (mFI = 0). Additionally, 9466 patients had a frailty score of 1 (27.4%), 2505 had a score of 2 (7.2%), 226 had a score of 3 (0.7%), and 11 had a score of 4 or higher (0.0%). Albumin levels were available for 16,250 patients (47.0%), and among them, 1334 (8.2%) had hypoalbuminemia. Regression analyses showed that higher mFI scores were independent predictors of any, surgical, and medical complications, as well as increased rates of reoperations, unplanned readmissions, and prolonged hospital stays. Hypoalbuminemia independently predicted any, surgical, and medical complications, and higher mortality, reoperation, and longer hospital stay. When both frailty and albumin levels (mFI-5 and albumin) were considered together, this combined assessment was found to be a more accurate predictor of all major outcomes (any, medical and surgical complications, mortality, and reoperation). Further, our analysis identified a weak negative correlation between serum albumin levels and mFI scores (Spearman R: -.1; p < .0001).

CONCLUSION

In conclusion, this cohort study highlights the association of hypoalbuminemia with adverse postoperative outcomes, including those not directly related to frailty. Simultaneously, higher mFI scores independently predicted outcomes not associated with hypoalbuminemia. Stemming from these findings, we recommend considering both serum albumin levels and frailty in patients receiving FFR. This perioperative algorithm may help provide more individualized planning including multidisciplinary care and pre and posthabilitation.

Can Preoperative Laboratory Values Predict Short-term Postoperative Complications and Health Utilization in Patients Undergoing Cranioplasty?

BACKGROUND

Low hematocrit, low albumin, and high creatinine levels have been associated with postoperative morbidity. The present study intends to analyze the effects of preoperative laboratories on medical complications and postoperative health resource utilization in patients undergoing cranioplasty.

METHODS

Using data from the American College of Surgeons National Surgical Quality Improvement Program, demographic, clinical, and intraoperative characteristics were collected for each patient who had recorded albumin, hematocrit, or creatinine laboratory values within 90 days of the index cranioplasty. Outcomes analyzed were ≥1 medical complication, ≥1 wound complication, unplanned reoperation, 30-day readmission, and extended hospital stay (>30 d). Outcomes significant on bivariate analyses were evaluated using multivariate logistic regression. Significant outcomes on multivariate analyses were analyzed using receiver operating characteristic curves and Mann-Whitney U tests.

RESULTS

The 3 separate cohorts included 1349 patients with albumin, 2201 patients with hematocrit, and 2182 patients with creatinine levels. Upon multivariate analysis, increases in albumin and hematocrit were independently associated with decreased odds of medical complications and extended length of stay. Increases in creatinine were independently associated with increased odds of medical complications. Discriminative cutoff values were identified for albumin and hematocrit.

CONCLUSIONS

Preoperative laboratory values were independent predictors of medical complications and health utilization following cranioplasty in this study. Surgical teams can use these findings to optimize preoperative risk stratification.

Risk predictions of hospital-acquired pressure injury in the intensive care unit based on a machine learning algorithm

Pressure injury (PI), or local damage to soft tissues and skin caused by prolonged pressure, remains controversial in the medical world. Patients in intensive care units (ICUs) were frequently reported to suffer PIs, with a heavy burden on their life and expenditures. Machine learning (ML) is a Section of artificial intelligence (AI) that has emerged in nursing practice and is increasingly used for diagnosis, complications, prognosis, and recurrence prediction. This study aims to investigate hospital-acquired PI (HAPI) risk predictions in ICU based on a ML algorithm by R programming language analysis. The former evidence was gathered through PRISMA guidelines. The logical analysis was applied via an R programming language. ML algorithms based on usage rate included logistic regression (LR), Random Forest (RF), Distributed tree (DT), Artificial neural networks (ANN), SVM (Support Vector Machine), Batch normalisation (BN), GB (Gradient Boosting), expectation-maximisation (EM), Adaptive Boosting (AdaBoost), and Extreme Gradient Boosting (XGBoost). Six cases were related to risk predictions of HAPI in the ICU based on an ML algorithm from seven obtained studies, and one study was associated with the Detection of PI risk. Also, the most estimated risksSerum Albumin, Lack of Activity, mechanical ventilation (MV), partial pressure of oxygen (PaO2), Surgery, Cardiovascular adequacy, ICU stay, Vasopressor, Consciousness, Skin integrity, Recovery Unit, insulin and oral antidiabetic (INS&OAD), Complete blood count (CBC), acute physiology and chronic health evaluation (APACHE) II score, Spontaneous bacterial peritonitis (SBP), Steroid, Demineralized Bone Matrix (DBM), Braden score, Faecal incontinence, Serum Creatinine (SCr) and age. In sum, HAPI prediction and PI risk detection are two significant areas for using ML in PI analysis. Also, the current data showed that the ML algorithm, including LR and RF, could be regarded as the practical platform for developing AI tools for diagnosing, prognosis, and treating PI in hospital units, especially ICU.

Retrospective study on the factors influencing the severity of pressure injuries among intensive care unit patients

AIMS AND OBJECTIVES

This study investigated the factors of pressure injuries in patients in intensive care units (ICU).

BACKGROUND

Pressure injuries among patients in ICUs can be prevented by the early assessment of risk factors and taking appropriate preventative measures.

DESIGN

A retrospective study.

METHODS

ICU patients who suffered from pressure injuries between January 2016 and August 2018 at a hospital in Taiwan were selected. Patient medical histories and data associated with pressure injuries and medical treatment were collected from electronic medical records. A total of 256 patients were included in our analysis. The study adhered to the STROBE checklist.

RESULTS

A multivariate model of multinomial logistic regression analysis indicated that when compared to Stage 1 pressure injuries, Stage 2-4 pressure injuries were associated with albumin levels. Patients with lower albumin levels were at greater odds of Stage 2-4 pressure injuries than Stage 1 pressure injuries. In addition, when compared to unstageable pressure injuries or deep tissue injuries, Stage 1 pressure injuries were associated with the use of fentanyl and haemoglobin levels. Patients using fentanyl were more likely to suffer from unstageable pressure injuries, and those with lower haemoglobin levels were more likely to suffer from unstageable pressure injuries or deep tissue injuries.

CONCLUSION

When patients were simultaneously on ventilators and taking midazolam or fentanyl, the incidence of pressure injuries with greater severity became higher. Furthermore, ICU patients with lower albumin and haemoglobin levels were more likely to suffer from pressure injuries of greater severity.

RELEVANCE TO CLINICAL PRACTICE

For critically ill patients on ventilators, it is recommended to devise a means of assessing each patient daily as well as systematically reduce their dosage of midazolam or fentanyl. Furthermore, regularly monitoring albumin and haemoglobin levels to understand their nutritional status is necessary.

Analysis of influencing factors of serum total protein and serum calcium content in plasma donors

Background and objectives

The adverse effects of plasma donation on the body has lowered the odds of donation. The aim of this study was to investigate the prevalence of abnormal serum calcium and total serum protein related to plasma donation, identify the influencing factors, and come up with suggestions to make plasma donation safer.

Methods

Donors from 10 plasmapheresis centers in five provinces of China participated in this study. Serum samples were collected before donation. Serum calcium was measured by arsenazo III colorimetry, and the biuret method was used for total serum protein assay. An automatic biochemical analyzer was used to conduct serum calcium and total serum protein tests.

Results

The mean serum calcium was 2.3 ± 0.15 mmol/L and total serum protein was 67.75 ± 6.02 g/L. The proportions of plasma donors whose serum calcium and total serum protein were lower than normal were 20.55% (815/3,966) and 27.99% (1,111/3,969), respectively. There were significant differences in mean serum calcium and total serum protein of plasma donors with different plasma donation frequencies, gender, age, regions, and body mass index (BMI), (all p < 0.05). Logistic regression analysis revealed that donation frequencies, age, BMI and regions were significantly associated with a higher risk of low serum calcium level, and donation frequencies, gender, age and regions were significant determinants factors of odds of abnormal total serum protein.

Conclusions

Donation frequencies, gender, age, regions, and BMI showed different effects on serum calcium and total serum protein. More attention should be paid to the age, donation frequency and region of plasma donors to reduce the probability of low serum calcium and low total serum protein.

The Association between Serum Albumin and Post-Operative Outcomes among Patients Undergoing Common Surgical Procedures: An Analysis of a Multi-Specialty Surgical Cohort from the National Surgical Quality Improvement Program (NSQIP)

While studies have demonstrated an association between preoperative hypoalbuminemia and adverse clinical outcomes, the optimal serum albumin threshold for risk-stratification in the broader surgical population remains poorly defined. We sought define the optimal threshold of preoperative serum albumin concentration for risk-stratification of adverse post-operative outcomes. Using the American College of Surgeons National Surgical Quality Improvement Program Database, we identified 842,672 patients that had undergone a common surgical procedure in one of eight surgical specialties. An optimal serum albumin concentration threshold for risk-stratification was determined using receiver-operating characteristic analysis. Multivariable logistic regression analysis was used to evaluate the odds of adverse surgical events; a priori defined subgroup analyses were performed. A serum albumin threshold of 3.4 g/dL optimally predicted adverse surgical outcomes in the broader cohort. After multivariable analysis, patients with hypoalbuminemia had increased odds of death within 30 days of surgery (odds ratio [OR] 2.01, 95% confidence interval [CI] 1.94–2.08). Hypoalbuminemia was associated with greater odds of primary adverse events among patients with disseminated cancer (OR 2.03, 95% CI 1.88–2.20) compared to patients without disseminated cancer (OR 1.47, 95% CI 1.44–1.51). The standard clinical threshold for hypoalbuminemia is the optimal threshold for preoperative risk assessment.

Risk Factors for Postoperative Pneumonia in the Elderly Following Hip Fracture Surgery: A Systematic Review and Meta-Analysis

Introduction: Pneumonia is a serious complication following hip fracture surgery in older people. However, the prevalence and risk factors of postoperative pneumonia (POP) are not well-established. This study identified pre- and peri-operative factors associated with the development of POP following hip fracture surgery. Methods: We searched the Cochrane library, PubMed, and Embase databases for relevant articles published up to June 2021. Studies involving older patients who underwent hip fracture surgery were considered if they detailed the demographic or surgical characteristics of the participants. For all analyses, the pooled odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated. Results: A total of 24 studies (288819 participants) were included. The overall prevalence of POP following hip fracture surgery was 5.0%. There were 36 risk factors for POP, and the meta-analysis included the five most common: delayed surgery (OR: 1.84, 95% CI: 1.29-2.63), low serum albumin (OR: 2.34, 95% CI: .82-6.73), chronic respiratory diseases (OR: 2.42, 95% CI: 1.82-3.24), increased age (OR: 1.25, 95% CI:1.11-1.40), and male sex (OR: 2.22, 95% CI: 2.00-2.47). Conclusions: The prevalence of POP was 5.0% following hip fracture surgery in the elderly. Older age, male sex, chronic respiratory diseases, delayed surgery, and low serum albumin were significant risk factors. Clinicians treating hip fracture patients must remain be aware of these risk factors.

The risk factors and predictive nomogram of human albumin infusion during the perioperative period of posterior lumbar interbody fusion: a study based on 2015-2020 data from a local hospital

BACKGROUND

Perioperative hypoalbuminemia of the posterior lumbar interbody fusion (PLIF) can increase the risk of infection of the incision site, and it is challenging to accurately predict perioperative hypoproteinemia. The objective of this study was to create a clinical predictive nomogram and validate its accuracy by finding the independent risk factors for perioperative hypoalbuminemia of PLIF.

METHODS

The patients who underwent PLIF at the Affiliated Hospital of Qingdao University between January 2015 and December 2020 were selected in this study. Besides, variables such as age, gender, BMI, current and past medical history, indications for surgery, surgery-related information, and results of preoperative blood routine tests were also collected from each patient. These patients were divided into injection group and non-injection group according to whether they were injected with human albumin. And they were also divided into training group and validation group, with the ratio of 4:1. Univariate and multivariate logistic regression analyses were performed in the training group to find the independent risk factors. The nomogram was developed based on these independent predictors. In addition, the area under the curve (AUC), the calibration curve and the decision curve analysis (DCA) were drawn in the training and validation groups to evaluate the prediction, calibration and clinical validity of the model. Finally, the nomograms in the training and validation groups and the receiver operating characteristic (ROC) curves of each independent risk factor were drawn to analyze the performance of this model.

RESULTS

A total of 2482 patients who met our criteria were recruited in this study and 256 (10.31%) patients were injected with human albumin perioperatively. There were 1985 people in the training group and 497 in the validation group. Multivariate logistic regression analysis revealed 5 independent risk factors, including old age, accompanying T2DM, level of preoperative albumin, amount of intraoperative blood loss and fusion stage. We drew nomograms. The AUC of the nomograms in the training group and the validation group were 0.807, 95% CI 0.774-0.840 and 0.859, 95% CI 0.797-0.920, respectively. The calibration curve shows consistency between the prediction and observation results. DCA showed a high net benefit from using nomograms to predict the risk of perioperative injection of human albumin. The AUCs of nomograms in the training and the validation groups were significantly higher than those of five independent risk factors mentioned above (P < 0.001), suggesting that the model is strongly predictive.

CONCLUSION

Preoperative low protein, operative stage ≥ 3, a relatively large amount of intraoperative blood loss, old age and history of diabetes were independent predictors of albumin infusion after PLIF. A predictive model for the risk of albumin injection during the perioperative period of PLIF was created using the above 5 predictors, and then validated. The model can be used to assess the risk of albumin injection in patients during the perioperative period of PLIF. The model is highly predictive, so it can be clinically applied to reduce the incidence of perioperative hypoalbuminemia.

Effect of Vibrotherapy on Body Fatness, Blood Parameters and Fibrinogen Concentration in Elderly Men

Elderly people need activities that will positively contribute to a satisfactory process of getting older. Vibration training uses mechanical stimulus of a vibrational character that, similarly to other forms of physical activity, affects metabolic processes and conditions of health. The aim of this work was to assess the influence of thirty vibration treatments on body fatness, hematologic and rheologic indexes of blood, and proteinogram and fibrinogen concentration in elderly men’s blood. The study included twenty-one males, aged 60–70 years (mean age 65.3 ± 2.7), who were randomly assigned into a vibrotherapy group (VG) and took part in interventions on mattresses generating oscillatory-cycloid vibrations, and a control group (CG), without interventions. In all patients the following assessments were performed twice: an assessment of body fatness using the bioimpedance method, a complete blood count with a hematology analyzer, and erythrocyte aggregation by a laser-optical rotational cell analyzer; whereas, total plasma protein and fibrinogen values were established, respectively, by biuret and spectrophotometric methods. In order to compare the impact of vibrotherapy on changes in the analyzed variables, analysis of variance (ANOVA) or the Wilcoxon test were used. After applying thirty vibration treatments in the VG, a significant decrease in body fatness parameters was confirmed: BM (∆BM: −2.7 ± 2.0; p = 0.002), BMI (∆BMI: −0.9 ± 0.7; p = 0.002), BF (∆BF: −2.5 ± 2.5; p = 0.013), and %BF (∆%BF: −2.0 ± 2.7; p = 0.041), as well as in RBC (∆RBC: −0.1 ± 0.1; p = 0.035). However, changes in erythrocyte aggregation and proteinogram were not confirmed. It was found that after thirty treatments with VG, a significant decrease of fibrinogen level took place (∆ = −0.3 ± 0.3, p = 0.005). Application of thirty vibrotherapy treatments positively affected body fatness parameters and fibrinogen concentrations in the examined. However, further research should include a greater number of participants.

Perioperative Albumin Supplementation is Associated With Decreased Risk of Complications Following Microvascular Head and Neck Reconstruction

PURPOSE

Studies have demonstrated that low serum albumin levels are associated with a high postoperative complication rate after microvascular free flap reconstruction. The aim of this study was to investigate whether perioperative albumin supplementation reduced the postoperative complications of microvascular free flap reconstruction in oral and maxillofacial tumor resections.

PATIENTS AND METHODS

Patients who underwent microvascular free flap reconstruction during oral and maxillofacial tumor resections from January 2012 to December 2017 were enrolled in this retrospective study. The predictor variable was perioperative albumin supplementation. The primary outcome variables were surgery-associated postoperative complications, including local and systemic complications. The secondary outcome variables were the total duration of hospital stay, postoperative ICU admission rate, duration of ICU stay, and mortality during hospitalization.

RESULTS

In total, 315 patients met the criteria. Patients with serum albumin supplementation showed a lower rate of surgery-associated local complications (6.5 vs 21.6%) with an adjusted odds ratio (OR) of 0.24 (95% confidence interval (CI), 0.12 to 0.49, P < .001). The average postoperative hospital stay was significantly shortened for patients with albumin supplementation (12.56 ± 4.23 vs 15.34 ± 5.24 days, P < .001). However, albumin supplementation had no effect on systemic complications.

CONCLUSIONS

The results of this study suggest that perioperative albumin supplementation is associated with a decreased risk of local complications, shortened hospital stay, and decreased need for crystalloid infusion in patients who underwent oral and maxillofacial tumor resections with microvascular free flap reconstruction.

Phases of fluid management and the roles of human albumin solution in perioperative and critically ill patients

OBJECTIVE

Positive fluid balance is common among critically ill patients and leads to worse outcomes, particularly in sepsis, acute respiratory distress syndrome, and acute kidney injury. Restrictive fluid infusion and active removal of accumulated fluid are being studied as approaches to prevent and treat fluid overload. Use of human albumin solutions has been investigated in different phases of restrictive fluid resuscitation, and this narrative literature review was undertaken to evaluate hypoalbuminemia and the roles of human serum albumin with respect to hypovolemia and its management.

METHODS

PubMed/EMBASE search terms were: "resuscitation," "fluids," "fluid therapy," "fluid balance," "plasma volume," "colloids," "crystalloids," "albumin," "hypoalbuminemia," "starch," "saline," "balanced salt solution," "gelatin," "goal-directed therapy" (English-language, pre-January 2020). Additional papers were identified by manual searching of reference lists.

RESULTS

Restrictive fluid administration, plus early vasopressor use, may reduce fluid balance, but in some cases fluid overload cannot be entirely avoided. Deresuscitation, with fluid actively removed through diuretics or ultrafiltration, reduces duration of mechanical ventilation and intensive care unit stay. Combining hyperoncotic human albumin solution with diuretics increases hemodynamic stability and diuresis. Hyperoncotic albumin corrects hypoalbuminemia and raises colloid osmotic pressure, limiting edema formation and potentially improving endothelial function. Serum levels of albumin relative to C-reactive protein and lactate may predict which patients will benefit most from albumin therapy.

CONCLUSIONS

Hyperoncotic human albumin solution facilitates restrictive fluid therapy and the effectiveness of deresuscitative measures. Current evidence is mostly from observational studies, and more randomized trials are needed to better establish a personalized approach to fluid management.

Perioperative Risk Factors for Radial Forearm-Free Flap Complications

PURPOSE

To determine perioperative risk factors predicted complications in elderly Chinese patients undergoing oral and maxillofacial reconstruction with radial forearm free flaps (RFFF).

PATIENTS AND METHODS

The authors implemented a retrospective study and enrolled a sample of patients at least 65-year old who underwent resection of oral and maxillofacial tumors and RFFF reconstruction from January 2011 to June 2018. Predictor variables were divided into: demographic variables (gender, age, weight, comorbidities, history of smoking, radiotherapy history, primary lesions); hemodynamic (preoperative and postoperative hemoglobin and albumin level, blood loss, blood transfusion, urine output (mL), and rate (mL/kg/h), and infusion rates for crystalloids and colloids (mL/kg/h, and volumes given intraoperatively and postoperatively for 24 hours); anesthetic and surgical (American Society of Anesthesiologists classification, visual analogue score, duration of tourniquet, and operation). The primary outcome was the presence of postoperative complications (yes/no), and secondary outcome was types of complications (medical and surgical). All the variables were analyzed by univariate and multivariable analysis and statistical significance was set at a P < 0.05 RESULTS:: The study sample was composed of 118 patients with a mean age of 72 years. There were 15 complications, of which 9 were surgical and 6 medical. Risk factors were: postoperative hypoproteinemia, crystal in 24 hours, and hypertension combined with diabetes.

CONCLUSIONS

Although reconstruction with a RFFF is a common and safe treatment for elderly patients with oral and maxillofacial tumors, postoperative hypoproteinemia, crystal in 24 hours, and hypertension combined with diabetes are potential predictors of postoperative complications.

Preoperative Serum Albumin Level As A Predictor Of Postoperative Pneumonia After Femoral Neck Fracture Surgery In A Geriatric Population

Purpose

Femoral neck fracture usually occurs in the geriatric population. Postoperative pneumonia (POP) is known to be devastated, and it is the most frequent complication among patients receiving surgical treatment for femoral neck fractures. However, whether patients who have hypoalbuminaemia are susceptible to the development of POP is a serious concern, although it has not been investigated. We attempted to investigate the association between newly developed POP and hypoalbuminaemia and to identify whether hypoalbuminaemia is an independent risk factor for POP after femoral neck fracture in geriatric population.

Patients and methods

We retrospectively reviewed the records from the first 30 days after surgery of patients who were ≥65 years of age and who had a femoral neck fracture treated with surgery between January 2018 and December 2018 at the Honghui Hospital, Xi’an Jiaotong University. Patients were divided into two groups based on whether they did or did not experience POP, and their clinical characteristics were compared. Binomial logistic regression was used to identify potential risk factors of POP by analysing demographic factors, preoperative comorbidities, laboratory results, and surgical factors.

Results

A total of 720 patients were included in the analysis, and 54 patients experienced POP. The incidence of POP after surgical treatment for a femoral neck fracture in this geriatric population was 7.5%. In addition, patients with POP had significantly longer hospital stays than patients without POP. The binary logistic regression analysis revealed that preoperative hypoalbuminaemia [odds ratio =5.187, 95% confidence interval (CI): 2.561–10.506, P<0.0001], COPD (OR =3.819, 95% CI: 1.247–11.701, P=0.019), prior stroke (OR =3.107, 95% CI: 1.470–6.568, P=0.003) and the time from injury to surgery (OR =1.076, 95% CI: 1.034–1.119, P<0.0001) were predominant and independent risk factors associated with POP after femoral neck fracture in this geriatric population.

Conclusion

The current study revealed that among a geriatric population admitted for femoral neck fracture surgery, preoperative hypoalbuminaemia was a predictor of POP, followed by COPD, prior stroke and the time from injury to surgery. Thus, patients who undergo femoral neck fracture surgery and have preoperative hypoalbuminaemia should receive additional monitoring and perioperative care.

Preoperative serum albumin is associated with intra-abdominal infection following major hepatectomy

Background

Major hepatectomy is a complex surgical procedure with high morbidity. Intra‐abdominal infection (IAI) is common following hepatectomy and affects treatment outcomes. This study was performed to investigate perioperative factors and determine whether the preoperative serum albumin level is associated with IAI following major hepatectomy.

Methods

From January 2008 to December 2018, 268 patients underwent major hepatectomy. We retrospectively analyzed demographic data and preoperative and perioperative variables. IAI was defined as organ/space surgical site infection. Risk factors for IAI were analyzed by logistic regression analysis.

Results

In total, 268 patients were evaluated. IAI was observed in 38 patients (14.6%). The mortality rate in the IAI group was 15.7%. Multivariate logistic analysis confirmed that the serum albumin level (odds ratio 0.91; 95% confidence interval 0.84–0.97; P = 0.03) and operative duration (odds ratio 1.50; 95% confidence interval 1.18–1.91; P < 0.01) were independent factors associated with IAI. A logistic model using the serum albumin level and operative duration to estimate the probability of IAI was analyzed. The area under the receiver operating characteristic curve for predicting IAI was 0.78.

Conclusion

The serum albumin level and operative duration were independent factors predicting IAI following major hepatectomy.

Correlation of serum albumin and prognostic nutritional index with outcomes following pancreaticoduodenectomy

BACKGROUND

Pancreaticoduodenectomy (PD) is a complex surgical procedure with a high morbidity rate. The serious complications are major risk factors for poor long-term surgical outcome. Studies have reported an association between early postoperative prognostic nutritional index (PNI) and prediction of severe complications after abdominal surgery. However, there have been no studies on the use of early postoperative PNI for predicting serious complications following PD.

AIM

To analyze the risk factors and early postoperative PNI for predicting severe complications following PD.

METHODS

We retrospectively analyzed 238 patients who underwent PD at our hospital between January 2007 and December 2017. The postoperative complications were classified according to the Dindo-Clavien classification. Grade III-V postoperative complications were classified as serious. The risk factors for serious complications were analyzed by univariate analysis and multivariate logistic regression analysis.

RESULTS

Overall complications were detected in 157 of 238 patients (65.9%) who underwent PD. The grade III-V complication rate was 26.47% (63/238 patients). The mortality rate was 3.7% (9/238 patients). Multivariate logistic regression analysis revealed that preoperative serum albumin [odds ratio (OR): 0.883, 95% confidence interval (CI): 0.80-0.96; P < 0.01] and PNI on postoperative day 3 < 40.5 (OR: 2.77, 95%CI: 1.21-6.38, P < 0.05) were independent factors associated with grade III-V postoperative complications.

CONCLUSION

Perioperative albumin is an important factor associated with serious complications following PD. Low early postoperative PNI (< 40.5) is a predictor for serious complications.

Identification of Independent Risk Factors for Complications: A Retrospective Analysis of 163 Fibular Free Flaps for Mandibulofacial Reconstruction

PURPOSE

Fibular free flap transfer is a powerful tool available to the reconstructive surgeon when treating oral and maxillofacial defects, but complications still occasionally occur and predictive analysis focusing on this specific flap is limited in terms of risk factors for complication. The purpose of this study was to identify key variables associated with complications in patients undergoing fibular free flap transfer.

PATIENTS AND METHODS

The data of 163 consecutive patients who underwent fibular free flap surgery at the Department of Oral and Maxillofacial Surgery, Sun Yat-Sen Memorial Hospital of Sun Yat-Sen University, between 2012 and 2015 were reviewed retrospectively. Patient demographic data, laboratory data, surgical data, and fluid infusion-related data that may have an influence on free flap outcomes were recorded. Univariate and multivariate logistic regression analyses were used to identify relevant risk factors.

RESULTS

A total of 163 fibular free flaps were transferred for mandibulofacial reconstruction in 163 patients with a mean age of 50.9 years. Postoperative complications developed in 33 (20.2%). Multivariate analysis showed that free flap complications were significantly associated with radiotherapy history (odds ratio [OR], 5.12; P = .001), postoperative anemia (OR, 1.048; P = .041), postoperative hypoalbuminemia (OR, 0.844; P = .002), and prolonged operative time (OR, 1.005; P = .004).

CONCLUSIONS

Radiotherapy history, decreased postoperative hemoglobin and albumin levels, and prolonged operative time are potential predictors of postoperative complications after fibular free flap reconstruction for mandibulofacial defects.

Hypoalbuminemia and Clinical Outcomes: What is the Mechanism behind the Relationship?

Albumin has a number of important physiologic functions, which include maintaining oncotic pressure, transporting various agents (fatty acids, bile acids, cholesterol, metal ions, and drugs), scavenging free oxygen radicals, acting as an antioxidant, and exerting an antiplatelet effect. Hypoalbuminemia in adults, defined by an intravascular albumin level of <3.5 g/dL, is associated with poor postoperative outcomes in patients undergoing surgical intervention. Although the relationship of hypoalbuminemia and poor surgical outcome has been known for many years, the pathophysiology behind the relationship is unclear. Three theoretical constructs might explain this relationship. First, albumin might serve as a nutritional marker, such that hypoalbuminemia represents poor nutritional status in patients who go on to experience poor postoperative outcomes. Second, albumin has its own pharmacologic characteristics as an antioxidant or transporter, and therefore, the lack of albumin might result in a deficiency of those functions, resulting in poor postoperative outcomes. Or third, albumin is known to be a negative acute phase protein, and as such hypoalbuminemia might represent an increased inflammatory status of the patient, potentially leading to poor outcomes. A thorough review of the literature reveals the fallacy of these arguments and fails to show a direct cause and effect between low albumin levels per se and adverse outcomes. Interventions designed solely to correct preoperative hypoalbuminemia, in particular intravenous albumin infusion, do little to change the patient's course of hospitalization. While surgeons may use albumin levels on admission for their prognostic value, they should avoid therapeutic strategies whose main endpoint is correction of this abnormality.

Colorectal preOperative Surgical Score (CrOSS) for mortality in major colorectal surgery

BACKGROUND

Colorectal surgery carries a significant mortality risk, with reported rates of 1-6% for elective surgery and up to 22% in the emergency setting. Both clinicians and patients will benefit from being able to predict the likelihood of death before surgery. Recently, we have described and validated two risk stratification models for colorectal surgery, the Barwon Health 2012 and Association Française de Chirurgie models. However, these models are not suitable for assessment at patient's bedside. The purpose of this study is to develop a simplified preoperative model capable of predicting mortality following colorectal surgery.

METHODS

The new model is termed Colorectal preOperative Surgical Score (CrOSS). The development and internal validation of CrOSS was performed using a prospectively maintained colorectal database. External validation was performed using retrospective data. Univariate and multivariate analyses were performed in model development. Calibration and discrimination were used for model validation.

RESULTS

There were 474 and 389 consecutive colorectal surgeries at Geelong Hospital and Western Hospital. Overall mortality rates were 5.16% and 1.03%, respectively. Significant predictors for mortality were as follows: age ≥70, urgent operation, albumin ≤30 g/L and congestive heart failure (receiver operating characteristic (ROC) = 0.870, calibration P-value = 0.937). The predicted risk of mortality was stratified according to the risk profile of 0.39-66.51%. When validated externally, CrOSS predicted mortality accurately (ROC = 0.847, calibration P-value = 0.199).

CONCLUSIONS

A robust and simple preoperative model has been created to risk-stratify patients for colorectal surgery. This was successfully validated at another tertiary hospital.

Influence of intensive care treatment on the protein binding of sufentanil and hydromorphone during pain therapy in postoperative cardiac surgery patients

BACKGROUND

Our objective was to evaluate the effect of intensive care treatment on the protein binding of sufentanil and hydromorphone in cardiac surgery patients during postoperative analgesia using a target-controlled infusion (TCI) and patient-controlled analgesia (PCA).

METHODS

Fifty adult patients were enrolled in this prospective randomized study; of which, 49 completed the study (age range 40-81 yr). Sufentanil was administered as an analgesic intraoperatively, and hydromorphone was dosed after operation with TCI and PCA until 8 a.m. on the first postoperative day. Arterial plasma samples were collected for drug and protein concentration measurements up to 24 h after cardiac surgery. Corresponding patient data were collected from the electronic patient data system. After explorative data analysis with principal component analysis, multivariate regression analysis and non-linear mixed effects modelling was used to study the effect of treatment on protein binding.

RESULTS

Data of 35 patients were analysed. The median protein binding of sufentanil and hydromorphone was 88.4% (IQ range 85.7-90.5%) and 11.6% (IQ range 9.5-14.3%), respectively. Free fraction of sufentanil increased towards the end of the study period, whereas hydromorphone free fraction remained nearly constant. The total sufentanil concentration and volume balance were identified as significant covariates for the protein binding of sufentanil. For the protein binding of hydromorphone, no significant covariate effects were found.

CONCLUSIONS

Sufentanil protein binding was significantly dependent on changes in the total drug concentration and volume balance addressing the importance of adequate dosing and fluid-guided therapy. Hydromorphone protein binding was nearly constant throughout the study period.

CLINICAL TRIAL REGISTRATION

EudraCT 2011-003648-31 and ClinicalTrials.gov: NCT01490268.

Distribution of serum total protein in elderly Chinese

The serum total protein levels of the elderly possibly decrease gradually with aging. However, serum total protein levels are not suitable as a uniform reference standard for the elderly at different ages and genders. Thus, we investigated the total serum protein distribution in different gender and age groups of 11,453 elderly individuals aged ≥60 years and without liver or renal disease from Lianyungang, Jiangsu, China. The total protein levels (TPL) of these individuals exhibited normal distribution (Z = 1.206, P = 0.109), whereas the reference range (95% CI) was 54.1 g/L to 82.3 g/L. TPL was higher in females than in males for those aged between 60 and 75 years, whereas no significant difference was observed for those aged between 80 and 95 years. TPL was negatively correlated with age in males (r = −0.1342, P<0.05), females (r = −0.304, P<0.05), and the total group (r = −0.2136, P<0.05). TPL also decreased with aging and showed a faster rate in women than in men. These results indicated that an appropriate range of serum total protein based on age and gender differences should be used for clinical applications.

Evaluation of albumin structural modifications through cobalt-albumin binding (CAB) assay

Human serum albumin (HSA) is the most abundant protein in the human body. HSA injections prepared by fractionating human blood have mainly covered the demand for albumin to treat hypoalbuminemia, the state of low concentration of albumin in blood. HSA in solution may exist in various forms such as monomers, oligomers, polymers, or as mixtures, and its conformational change and/or aggregation may occur easily. Considering these characteristics, there is a great chance of modification and polymer formation during the preparation processes of albumin products, especially injections. The albumin cobalt binding (ACB) test reported by Bar-Or et al. was originally designed to detect ischemia modified albumin (IMA), which contains the modified HSA N-terminal sequence by cleavage of the last two amino acids. In this study, we developed a cobalt albumin binding (CAB) assay to correct the flaws of the ACB test with improving the sensitivity and precision. The newly developed CAB assay easily detects albumin configuration alterations and may be able to be used in developing a quality control method for albumin and its pharmaceutical formulations including albumin injections.

Albumin administration prevents the onset of pressure ulcers in intensive care unit patients

Pressure ulcers (PUs) are a common problem in critically ill patients admitted to the intensive care units (ICUs) and they account for more than 70% of patients with low serum albumin at admission. The aim of this study was to test the efficacy of intravenous administration of albumin in patients with low serum albumin < 3·3 g/dl. In a 1-year period, a total of 73 patients were admitted to the ICU (males 45, 61·64% and females 28, 38·36%); of these, 21 patients were admitted with hypoalbuminaemia (serum albumin < 3·3 g/dl) and randomised into two groups: 11 patients were treated with 25 g intravenous albumin for the first 3 days within the first week of ICU stay (group A) and 10 patients did not receive albumin (group B). Three patients (27·27%) showed the onset of PUs in group A, whereas seven patients (70%) showed the onset of PUs within the first 7 days of stay in group B. Moreover, ulcers of group B were more severe than those of group A. This study shows that intravenous administration of albumin reduces the onset of PUs in patients admitted to the ICU and in some cases it also reduces the risk of progression to advanced stages of PUs.

Low serum albumin level as an independent risk factor for the onset of pressure ulcers in intensive care unit patients

Critically ill patients are at high risk of developing pressure ulcers (PUs) and patients who develop PUs remain significantly longer in the intensive care unit (ICU) with significantly increased morbidity and mortality. Therefore, the identification of patients at truly increased risk is important. The aim of this study was to examine the association of low serum albumin present at admission in ICU patients with the onset of PUs. We conducted a retrospective cohort study on 610 patients who were admitted to intensive care unit. Level of serum albumin and other biochemical indices, recorded at the time of admission, were collected. We collected information about PU occurrence after admission and conducted a statistical analysis with biomarkers at ICU admission and during hospital stay. The incidence of PU in the ICUs was 31% and about 70% of patients with PUs had hypoalbuminemia at admission. The lowest values of serum albumin in patients with PUs were directly proportional to the severity of ulcers. In this study, we found a close association between serum albumin and PUs. In fact serum albumin was negatively correlated with PU and may be considered one of the independent determinants of PU occurrence in patients admitted to ICUs.