Departments of Radiology, Mayo Clinic, Rochester, MN 55905, USA.
J Neurosurg Spine. 2013 Mar;18(3):280-8. doi: 10.3171/2012.12.SPINE12300. Epub 2013 Jan 29.
The presence of a "July effect," where the influx of new residents and fellows at teaching hospitals every July may negatively affect patient care and outcomes, is widely debated. The authors used the Nationwide Inpatient Sample (NIS) to identify all cases of spinal surgery and examine outcomes among patients who underwent surgery in July compared with those who underwent surgery in other months.
Spinal surgery hospitalizations from 2001 to 2008 were identified in the NIS by extracting relevant ICD-9 codes. Rates of in-hospital mortality, discharge to a long-term care facility, and postoperative complications were compared between admission months and between teaching and nonteaching hospitals using the Wilcoxon rank-sum test, Fisher exact test, and multivariate regression analysis.
Compared with patients admitted in other months, patients who were admitted to teaching hospitals in July for spinal surgery showed a similar likelihood of in-hospital mortality (OR 0.94 [95% CI 0.78-1.11], p = 0.46), reaction to implanted device/instrumentation (OR 0.88 [95% CI 0.77-1.02], p = 0.09), and postoperative wound dehiscence (OR 1.12 [95% CI 0.94-1.33], p = 0.25). A significantly higher likelihood of discharge to a long-term care facility (OR 1.03 [95% CI 1.00-1.07], p = 0.0467) and postoperative infection (OR 1.11 [95% CI 1.05-1.17], p = 0.0341) was observed in teaching hospitals in July compared with other months; however, incidence rates were similar regardless of admission month. Higher-risk patients (Charlson score ≥ 2) admitted to teaching hospitals in July had a similar likelihood of all outcomes regardless of admission month.
This study of nationwide hospitalizations demonstrates that the influx of new residents and fellows in July has a negligible effect on periprocedural outcomes following spinal surgery.
教学医院每年 7 月新居民和研究员的涌入可能对患者护理和结果产生负面影响，这一“7 月效应”广泛存在争议。作者使用全国住院患者样本（NIS）确定所有脊柱手术病例，并比较 7 月手术患者与其他月份手术患者的结果。
通过提取相关 ICD-9 代码，从 NIS 中确定 2001 年至 2008 年脊柱手术住院患者。使用 Wilcoxon 秩和检验、Fisher 确切检验和多变量回归分析比较入院月份和教学医院与非教学医院之间的住院死亡率、转至长期护理机构以及术后并发症的发生率。
与其他月份入院的患者相比，7 月在教学医院接受脊柱手术的患者的院内死亡率（OR 0.94[95%CI 0.78-1.11]，p=0.46）、对植入器械的反应（OR 0.88[95%CI 0.77-1.02]，p=0.09）和术后伤口裂开（OR 1.12[95%CI 0.94-1.33]，p=0.25）的可能性相似。与其他月份相比，7 月在教学医院的患者更有可能转至长期护理机构（OR 1.03[95%CI 1.00-1.07]，p=0.0467）和术后感染（OR 1.11[95%CI 1.05-1.17]，p=0.0341），但无论入院月份如何，发生率相似。无论入院月份如何，7 月入住教学医院的高风险患者（Charlson 评分≥2）所有结局的可能性相似。
这项全国范围内的住院患者研究表明，7 月新居民和研究员的涌入对脊柱手术后围手术期结果几乎没有影响。
