Development and external validation of a predictive model for prolonged length of hospital stay in elderly patients undergoing lumbar fusion surgery: comparison of three predictive models.

PURPOSE: This study aimed to develop a predictive model for prolonged length of hospital stay (pLOS) in elderly patients undergoing lumbar fusion surgery, utilizing multivariate logistic regression, single classification and regression tree (hereafter, "classification tree") and random forest machine-learning algorithms. METHODS: This study was a retrospective review of a prospective Geriatric Lumbar Disease Database. The primary outcome measure was pLOS, which was defined as the LOS greater than the 75th percentile. All patients were grouped as pLOS group and non-pLOS. Three models (including logistic regression, single-classification tree and random forest algorithms) for predicting pLOS were developed using training dataset and internal validation using testing dataset. Finally, online tool based on our model was developed to assess its validity in the clinical setting (external validation). RESULTS: The development set included 1025 patients (mean [SD] age, 72.8 [5.6] years; 632 [61.7%] female), and the external validation set included 175 patients (73.2 [5.9] years; 97[55.4%] female). Multivariate logistic analyses revealed that older age (odds ratio [OR] 1.06, p < 0.001), higher BMI (OR 1.08, p = 0.002), number of fused segments (OR 1.41, p < 0.001), longer operative time (OR 1.02, p < 0.001), and diabetes (OR 1.05, p = 0.046) were independent risk factors for pLOS in elderly patients undergoing lumbar fusion surgery. The single-classification tree revealed that operative time ≥ 232 min, delayed ambulation, and BMI ≥ 30 kg/m2 as particularly influential predictors for pLOS. A random forest model was developed using the remaining 14 variables. Intraoperative EBL, operative time, delayed ambulation, age, number of fused segments, BMI, and RBC count were the most significant variables in the final model. The predictive ability of our three models was comparable, with no significant differences in AUC (0.73 vs. 0.71 vs. 0.70, respectively). The logistic regression model had a higher net benefit for clinical intervention than the other models. The nomogram was developed, and the C-index of external validation for PLOS was 0.69 (95% CI, 0.65-0.76). CONCLUSION: This investigation produced three predictive models for pLOS in elderly patients undergoing lumbar fusion surgery. The predictive ability of our three models was comparable. Logistic regression model had a higher net benefit for clinical intervention than the other models. Our predictive model could inform physicians about elderly patients with a high risk of pLOS after surgery.

Physicians' knowledge, attitude, and prescribing behavior regarding stress ulcer prophylaxis in China: a multi-center study.

BACKGROUND: Perioperative patients are at risk of developing stress ulcers (SU), which can cause clinically important bleeding. Stress ulcer prophylaxis (SUP) is widely applied to the patients in Intensive care unit (ICU) as well as the general ward, so it may lead to overmedication. However, there have been no surveys regarding SUP knowledge or prescribing habits. OBJECTIVE: Our study assessed the knowledge, attitudes, and prescribing behavior of the surgeons toward perioperative patients regarding SUP and determined factors associated with low knowledge and high level of prescribing behaviors. METHODS: We performed a cross-sectional survey using questionnaires, randomly sampling 1266 surgeons on their current SUP practices. RESULTS: Proton pump inhibitors for SUP were used the most (94%); 43% used lansoprazole. Guideline awareness was inconsistent; the most familiar guideline was the National Medical Journal of China, and 46% were unaware of any guidelines. The predictors of low knowledge score regarding SUP in multivariable analysis were the hospital grade (p = 0.000), the type of hospital (p = 0.044), attendance at continuing education programs (p = 0.037), the awareness of clinical practice guidelines (CPGs) for SUP (p = 0.000). Twenty-one percent of physicians were high prescribers. High prescribing behavior was associated with hospital grade(p = 0.000), education level(p = 0.010) and attendance at continuing education programs (p = 0.000). CONCLUSION: We found that most surgeons used SUP, primarily proton pump inhibitors. However, surgeons knew little about the SUP guidelines, which may lead to insufficient SUP knowledge and overmedication. In addition, hospital grade, the type of hospital and attendance at continuing education programs may also affect the low knowledge of SUP. Hospital grade, education level and attendance at continuing education programs may affect high prescribing behavior.

Comparative short-term outcomes of enhanced recovery after surgery (ERAS) program and non-ERAS traditional care in elderly patients undergoing lumbar arthrodesis: a retrospective study.

BACKGROUND: Enhanced recovery after surgery (ERAS) program is an evidence-based improvement over non-ERAS traditional care. The aim of the present study was to analyze the safety, feasibility, and efficacy of an ERAS program in patients over 70 years undergoing lumbar arthrodesis by comparison with non-ERAS traditional care. METHODS: During January 2018 to December 2018, patients enrolled received non-ERAS traditional care, while the ERAS program was implemented from January to December 2019. Demographic characteristics, comorbidities, surgical data and postoperative recovery parameters were collected from all patients. Postoperative pain scores were evaluated by visual analog scales (VAS). The clinical outcomes were length of stay (LOS), postoperative complications and postoperative pain scores. Compliance results were also collected. RESULT: A total of 127 patients were enrolled, including 67 patients in the non-ERAS traditional care group and 60 patients in the ERAS group. The demographic characteristics and comorbidities of the two groups showed no significant differences. The LOS of patients treated with ERAS program (13.6 ± 4.0 days) was significantly less than that of patients treated with non-ERAS traditional care (15.6 ± 3.9 days) (p = 0.034). Complication rate was 8.3% in the ERAS group versus 20.9% in the non-ERAS traditional care group (p = 0.048). VAS (back) in the ERAS group was significantly lower on postoperative day (POD) 1 and POD2. Postoperative recovery parameters were improved in the ERAS group. The overall compliance with the ERAS program was 94%. CONCLUSIONS: Based on our results, ERAS program is safer and more effective for elderly patients over 70 undergoing lumbar arthrodesis than non-ERAS traditional care.

A prospective comparative study of the MNA-SF and GNRI nutritional screening tools in predicting infectious complications among elderly patients over 70 years undergoing posterior lumbar arthrodesis.

Malnutrition is a risk factor for postoperative infectious complications of elderly patients undergoing posterior lumbar arthrodesis. At present, there is no gold standard for nutrition screening tools. We analyzed the value of predicting infectious complications among elderly patients over 70 years undergoing posterior lumbar arthrodesis by comparing the MNA-SF and GNRI. Demographic data, anthropometric measurements, serum albumin, surgical data and the occurrence of infectious complications and LOS were collected. Mini Nutritional Assessment short form (MNA-SF), Geriatric Nutritional Risk Index (GNRI) were performed within 24 h before surgery. Multivariable logistic regression analyses were used to identify predictors of infectious complications. The discriminatory performances of GNRI and MNA-SF scores for the occurrence of infectious complications were determined by receiver operating characteristic curves (ROC) analyses and the area under the curve (AUC). The study included 252 patients with a median age of 76.82 ± 6.41 years (range 70-84 years), and 142 patients (56.3%) were female. There were no significant differences in infectious complications (p = 0.236) and LOS (p = 0.580) among different GNRI categories. 27.3% malnourished patients evaluated by the MNA-SF suffered from infectious complications and 10.1% patients at risk of malnourished had infectious complications. Those patients had statistically significant higher prevalence of infectious complications (p = 0.002) and longer LOS (p = 0.023) than well-nourished patients. Multivariable analysis revealed that preoperative malnutrition and at risk of malnourished by the MNA-SF was significantly associated with infections. The area under the curve (AUC) of MNA-SF was 0.754, which was significantly high than AUC of GNRI (0.623) (Delong's test, p = 0.033). This study demonstrated that MNA-SF is a simple and effective tool for predicting the risk of infectious complications in elderly patients undergoing posterior lumbar arthrodesis.

Impact of Compliance with an Enhanced Recovery After Surgery Program on the Outcomes Among Elderly Patients Undergoing Lumbar Fusion Surgery.

BACKGROUND AND AIM: The benefits of the enhanced recovery after surgery (ERAS) program to elderly patients have not been evaluated in lumbar fusion surgery. Compliance with the ERAS program is associated with prognosis. There is currently no adequate assessment about the importance of the individual components of ERAS program in lumbar fusion surgery. The aim of the study was to analyze the effect of compliance with our ERAS program and the relative importance of the individual ERAS program components among elderly patients undergoing lumbar fusion surgery. METHODS: A retrospective case-review study was conducted from March 2018 to March 2020. The ERAS program for lumbar fusion surgery at our department was implemented. Overall compliance was found to be 92.9%, and this was used as a cutoff for dividing patients into higher compliance and lower compliance groups. Patient characteristics and clinical outcomes were compared between groups. RESULTS: The overall compliance rate was 92.9%, distributing 91 patients into the higher compliance group and 169 patients into the lower compliance group. Patients with higher compliance were younger (p=0.045). The length of stay (LOS) of patients with higher compliance was significantly shorter than that of patients with lower compliance. Patients with higher compliance had significantly fewer complications (p=0.031). A multivariate analysis showed that surgical time (p=0.029), lower compliance (p=0.034), and early oral feeding (p=0.026) were predictors of any postoperative complications. On multivariate analysis, the following items remained correlated with prolonged LOS (LOS≥12 days): older age (p=0.010), lower compliance (p<0.0001), early ambulation (p=0.018), and stick to discharge criteria (p=0.040). CONCLUSION: Low compliance with ERAS program among elderly patients undergoing lumbar fusion surgery was associated with a higher incidence of complications and prolonged LOS. The failure of early oral feeding was associated with increased complications, and the failure of early ambulation or sticking to discharge criteria was significantly more influential on prolonged LOS.

Role of BKCa in Stretch-Induced Relaxation of Colonic Smooth Muscle.

Stretch-induced relaxation has not been clearly identified in gastrointestinal tract. The present study is to explore the role of large conductance calcium-activated potassium channels (BKCa) in stretch-induced relaxation of colon. The expression and currents of BKCa were detected and the basal muscle tone and contraction amplitude of colonic smooth muscle strips were measured. The expression of BKCa in colon is higher than other GI segments (P < 0.05). The density of BKCa currents was very high in colonic smooth muscle cells (SMCs). BKCa in rat colonic SMCs were sensitive to stretch. The relaxation response of colonic SM strips to stretch was attenuated by charybdotoxin (ChTX), a nonspecific BKCa blocker (P < 0.05). After blocking enteric nervous activities by tetrodotoxin (TTX), the stretch-induced relaxation did not change (P > 0.05). Still, ChTX and iberiotoxin (IbTX, a specific BKCa blocker) attenuated the relaxation of the colonic muscle strips enduring stretch (P < 0.05). These results suggest stretch-activation of BKCa in SMCs was involved in the stretch-induced relaxation of colon. Our study highlights the role of mechanosensitive ion channels in SMCs in colon motility regulation and their physiological and pathophysiological significance is worth further study.