Akash J. Patel, Ahilan Sivaganesan, Robert J. Bollo, Alison Brayton, Thomas G. Luerssen, and Andrew Jea
Recent attempts to control health care costs focus on reducing or eliminating payments for complications, hospital-acquired conditions, and provider preventable conditions, with payment restrictions applied uniformly. A patient's preexisting comorbidities likely influence the perioperative complication incidence. This relationship has not previously been examined in pediatric neurosurgery.
The authors conducted a retrospective assessment of prospectively collected relevant patient comorbidities and morbidity and mortality events at a large pediatric neurosurgical unit over a 5-year period. The authors examined the impact of specific comorbidities and the cumulative effect of multiple comorbidities on complication incidence.
A total of 1990 patients underwent 3195 procedures at the authors' institution during the 5-year study period. Overall, 396 complications were analyzed; 298 patients (15.0%) experienced at least one complication. One or more comorbidities were present in 45.9% of patients. Renal comorbidities were clearly associated with the increased incidence of complications (p = 0.02), and they were specifically associated with infection (p = 0.006). Neurological comorbidities had a borderline association with complications (p = 0.05), and they were specifically associated with death (p = 0.037). A patient's having more comorbidities did not correlate with an increased risk of a perioperative complication (p = 0.8275).
The complication incidence in pediatric neurosurgery is variable and may be influenced by the type of neurosurgical procedure and patient-related factors. While patient-related factors beyond the control of the provider can significantly impact complications and hospital-acquired conditions in pediatric neurosurgery, an increasing number of comorbidities do not correlate with an increased risk of complications per patient.
Deshdeepak Sahni, Andrew Jea, Javier A. Mata, Daniela C. Marcano, Ahilan Sivaganesan, Jacob M. Berlin, Claudio E. Tatsui, Zhengzong Sun, Thomas G. Luerssen, Shiyun Meng, Thomas A. Kent, and James M. Tour
Graphene possesses unique electrical, physical, and chemical properties that may offer significant potential as a bioscaffold for neuronal regeneration after spinal cord injury. The purpose of this investigation was to establish the in vitro biocompatibility of pristine graphene for interface with primary rat cortical neurons.
Graphene films were prepared by chemical vapor deposition on a copper foil catalytic substrate and subsequent apposition on bare Permanox plastic polymer dishes. Rat neuronal cell culture was grown on graphene-coated surfaces, and cell growth and attachment were compared with those on uncoated and poly-d-lysine (PDL)-coated controls; the latter surface is highly favorable for neuronal attachment and growth. Live/dead cell analysis was conducted with flow cytometry using ethidium homodimer-1 and calcein AM dyes. Lactate dehydrogenase (LDH) levels—indicative of cytotoxicity—were measured as markers of cell death. Phase contrast microscopy of active cell culture was conducted to assess neuronal attachment and morphology.
Statistically significant differences in the percentage of live or dead neurons were noted between graphene and PDL surfaces, as well as between the PDL-coated and bare surfaces, but there was little difference in cell viability between graphene-coated and bare surfaces. There were significantly lower LDH levels in the graphene-coated samples compared with the uncoated ones, indicating that graphene was not more cytotoxic than the bare control surface. According to phase contrast microscopy, neurons attached to the graphene-coated surface and were able to elaborate long, neuritic processes suggestive of normal neuronal metabolism and morphology.
Further use of graphene as a bioscaffold will require surface modification that enhances hydrophilicity to increase cellular attachment and growth. Graphene is a nanomaterial that is biocompatible with neurons and may have significant biomedical applications.
Daniel H. Fulkerson, Ahilan Sivaganesan, Jason D. Hill, John R. Edwards, Mohammadali M. Shoja, Joel C. Boaz, and Andrew Jea
The physiological reaction of CSF white blood cells (WBCs) over the course of treating a shunt infection is undefined. The authors speculated that the CSF WBC count varies with different infecting organisms in peak level and differential percentage of polymorphonuclear (PMN) leukocytes, lymphocytes, monocytes, and eosinophils. The authors hope to identify clinically useful trends in the progression of CSF WBCs by analyzing a large group of patients with successfully treated shunt infections.
The authors reviewed 105 successfully treated cases of shunt infections at Riley Hospital for Children. The study dates ranged from 2000 to 2004; this represented a period prior to the routine use of antibiotic-impregnated shunt catheters. They analyzed the following organisms: coagulase-negative staphylococci, Staphylococcus aureus, Propionibacterium acnes, Streptococcal species, and gram-negative organisms. The initial CSF sample at diagnosis was analyzed, as were levels over 14 days of treatment. Model fitting was performed to generate curves for the expected progression of the WBC counts and the differential PMN leukocytes, lymphocyte, monocyte, and eosinophil percentages.
Gram-negative organisms resulted in a higher initial (p = 0.03) and peak WBC count with a greater differential of PMN leukocytes compared with other organisms. Propionibacterium acnes infections were associated with a significantly lower WBC count and PMN leukocytes percentage (p = 0.02) and higher eosinophil percentage (p = 0.002) than other organisms. The pattern progression of the CSF WBC count and differential percentages was consistent for all infections. There was an initial predominance of PMN leukocytes, followed by a delayed peak of lymphocytes, monocytes, and eosinophils over a 14-day course. All values trended toward zero over the treatment course.
The initial and peak levels of CSF WBCs vary with the infecting organisms. The CSF cell counts showed a predictable pattern during the treatment of shunt infection. These trends may be useful to the physician in clinical decision making, although there is a wide range of variability.