Kevin J. Gibbons

Pneumonia: incidence, risk factors, and outcome in injured patients.

One hundred thirty (44.2%) of 294 patients hospitalized for trauma and admitted to the Surgical Intensive Care Unit for mechanical ventilation developed hospital-acquired bacterial pneumonia. The predominant pathogens isolated were gram-negative enteric bacilli (72%), but there was not an increase in mortality associated with gram-negative pneumonia compared with similar patients without pneumonia. Of the seven admission risk factors univariately associated with the development of acquired bacterial pneumonia, only emergent intubation (p less than 0.001), head injury (p less than 0.001), hypotension on admission (p less than 0.001), blunt trauma as the mechanism of injury (p less than 0.001), and Injury Severity Score (p less than 0.001) remained significant after stepwise logistic regression. Not surprisingly, as mechanical ventilation is continued, the probability of pneumonia emerging increases. The consequences of hospital-acquired bacterial pneumonia are a significant seven-, five-, and two-fold increase in mechanically ventilated days, intensive care, and hospital stay, respectively. We conclude that the incidence of hospital-acquired pneumonia in injured patients admitted to the ICU for mechanical ventilation occurs in nearly half the patients, is associated with specific risk factors, and significantly increases morbidity but does not increase mortality.

Acute Ischemic Stroke and Infections

We present an overview of multiple infections in relation to acute ischemic stroke and the therapeutic options available. Conditions that are a direct cause of stroke (infectious endocarditis, meningoencephalitides, and human immunodeficiency virus infection), the pathophysiologic mechanism responsible for stroke, and treatment dilemmas are presented. Independently or in conjunction with conventional risk factors, chronic and acute infections can trigger an acute ischemic stroke through an accelerated process of atherosclerosis and immunohematologic alterations. Acute ischemic stroke has a negative impact on the antibacterial immune response, leading to stroke-induced immunodepression and infections, the most common poststroke medical complications. Poststroke infections are independent predictors of poor outcome. Antibiotic trials for poststroke infection prevention are reviewed. Although antibiotic prophylaxis is not the standard of care in acute stroke, current guidelines support prompt treatment of stroke-related infections.

Thrombolysis of the cervical internal carotid artery before balloon angioplasty and stent placement: report of two cases.

The application of endovascular techniques to the treatment of cervical carotid artery bifurcation atherosclerosis has been delayed because of the fear of causing embolic events while traversing the diseased portion of the artery with an angioplasty balloon catheter. Symptomatic carotid arteries often contain fresh or partially digested intraluminal thrombus. Before we cross certain carotid bifurcation lesions with angioplasty catheters, we deliver 100,000 to 200,000 units of urokinase in an attempt to digest loose thrombus. We have witnessed changes in the angiographic appearance of the diseased portion of the vessel after urokinase treatment, such as widening of the lumen, that suggest clot lysis. We present two patients who had symptomatic internal carotid artery stenosis. Angiography showed irregular narrowing of the internal carotid artery origin. One patient was selected for angioplasty instead of carotid endarterectomy because of severe cardiac risk factors. The other patient had major angiographic risk factors manifested by poor collateral circulation. The angiographic findings and history of transient ischemic attacks led us to suspect the presence of soft, loose plaque debris or thrombus in both cases. Therefore, we performed thrombolysis with urokinase before angioplasty. Repeat angiography showed widening of the arterial lumen and smoothing of the plaque profile. Subsequent angioplasty and stent placement were uneventful. Intraarterial thrombolysis can produce a change in the angiographic appearance of symptomatic atherosclerotic lesions of the cervical carotid artery bifurcation. Digestion of intralesional thrombus may provide a safer environment for deployment of endovascular remodeling devices by decreasing the likelihood of embolic phenomena. We believe thrombolysis should be done before angioplasty in select patients.

Microvascular surgical anatomy of the vertebrobasilar junction

OBJECTIVE We examined the pertinent microvascular anatomy of 28 formalin-fixed brains to develop anatomic guidelines for aneurysm surgery in the region of the vertebrobasilar junction. METHODS Using a surgical microscope, the outer diameters were observed for the following main arteries: vertebral, basilar, posteroinferior cerebellar, and anteroinferior cerebellar. The number of lower brain stem perforating arteries was examined in relation to their course. The distance between the arteries and their perforators was measured with respect to anatomic landmarks. RESULTS The anatomy of the main arteries was characteristically variable, whereas the anatomy of the perforators was constant, particularly in terms of their numbers and points of penetration into the brain substance. The four major points of entry were the lateral medullary area just caudal to the posterior olivary sulcus, the posterior olivary sulcus, the small lateral fossa at the superior olivary groove, and the foramen cecum. Each of these areas coincides with the origin of common vertebrobasilar aneurysms. CONCLUSION The anatomy of the main arteries was variable. In contrast, the perforators penetrated the adjoining brain stem at specific locations, regardless of the caliber of the main artery. Despite a small vertebral artery or its major branches, perforators penetrating the brain are significant and may effect the outcome of aneurysm surgery or endovascular procedures.

Lumbar discectomy: use of an epidural morphine sponge for postoperative pain control.

A technique for extended ambulatory epidural pain control after lumbar discectomy is described; preliminary results with 45 patients are reported; and alternative methods of narcotic analgesia are reviewed. In this technique, an absorbable gelatin sponge (Gelfoam, Upjohn Co., Kalamazoo, MI) is contoured to the laminotomy defect, placed in methylprednisolone acetate (40-80 mg), and then injected with 2 to 4 mg of preservative-free morphine (a small needle was used to fill the sponge). The sponge is placed over the defect before closure. A review of office and hospital records was conducted. The series consisted of 33 men and 12 women (mean age, 39 yr; range, 24-57 yr); records showed narcotic use in 34 patients (parenteral in 3) and work-related injuries in 14 patients. Thirty-three patients were ambulatory postoperatively on the day of surgery; all were ambulatory by postoperative day (POD) 1. On the day of surgery, 18 patients did not require any postoperative analgesics; on POD 1, 22 patients did not require analgesics. Six patients received parenteral narcotics; four received one dose only, and two had two or more doses. Thirty-one patients were discharged from the hospital on POD 1, and 10 were discharged POD 2. The other patients were discharged from the hospital on POD 3 (three patients) or POD 4 (one patient). When they were discharged, all patients received a limited supply of acetaminophen with codeine for pain control at home. After discharge, phone follow-up (at 1 week) and office follow-ups (at 3-5 weeks) revealed only one patient with more than mild discomfort. Three patients required one-time bladder catheterization, and one patient had presumed discitis 1 month postoperatively. In a control group who had undergone surgery 3 months previously, the average day of discharge had been POD 3.07; no control patient had been discharged on POD 1, and only 20% had been discharged on POD 2. This method provides effective, safe, and extended analgesia after lumbar discectomy.

Spinal leptomeningeal hemangioblastomatosis in von Hippel-Lindau disease: magnetic resonance and pathological findings.

A 55–year–old man with von Hippel–Lindau disease presented with quadriparesis. Muitiple enhancing cervical and thoracic spinal masses were seen on magnetic resonance imaging (MRI). A rim of diffuse, nodular enhancement linking all of the discrete masses was apparent on the surface of the cervical and thoracic regions of the cord. Surgical exploration revealed multiple extramedullary–intradural and intramedullary masses, extending to and infiltrating the cord; the leptomeninges contained numerous small tumor seeds at several levels. The excised spinal masses were diagnosed as capillary hemangioblastomas, which infiltrated the pia mater. Diffuse, intense, spinal leptomeningeal enhancement on MRI associated with multiple hemangioblastomas has not been previously reported and may be referred to as spinal “leptomeningeal hemangioblastomatosis.”

CT perfusion cerebral blood flow imaging in neurological critical care

Computed tomography (CT) perfusion imaging is a technique for the measurement of cerebral blood flow, cerebral blood volume, and time-to-peak or mean transit time. The technique involves the administration of a single-bolus dose of iodinated contrast material, followed by spiral CT imaging during the passage of the contrast bolus through the cerebral vasculature. CT perfusion is a fast and inexpensive brain imaging modality for use in the management of patients with various neurological disorders, ranging from acute stroke to subarachnoid hemorrhage. This article reviews the technique of CT perfusion and presents several illustrative cases in which this imaging modality was used effectively in the critical care of patients with neurological disorders.

Submaximal angioplasty and staged stenting for severe posterior circulation intracranial stenosis: a technique in evolution.

AbstractIntroduction: Severe medically refractory intracranial stenosis portends a grave prognosis. Recent advances in stent technology have enabled clinicians to treat these lesions. Evidence in the coronary literature suggests that stenting without predilation angioplasty is as safe and effective as stenting immediately preceded by predilation angioplasty for the treatment of severely stenotic lesions. Because of marked differences in vessel histology and differences in the sensitivity of the cerebral and coronary vascular beds to embolic insult, direct stenting of severe intracranial stenoses may be more prone to neurological complications than a conventional or staged stenting procedure. Methods: We reviewed our clinical experience with conventional, direct, and staged stenting for high-grade stenoses involving the posterior intracranial circulation. We also reviewed the literature and experimental data supporting the rationale for staged stenting. Results: In our experience, no permanent neurological morbidity was identified in four patients treated with a staged approach. In contrast, one of three patients with conventional stenting of the basilar artery and two of four patients treated with direct basilar stenting had permanent neurological sequelae. Conclusion: For patients with high-grade posterior circulation intracranial stenoses involving the perforator-rich zones of the basilar artery, staged stenting may reduce procedure-related morbidity. A staged approach allows for plaque stabilization resulting from postangioplasty fibrosis, which may protect patients from “snowplowing,” embolic shower of debris, or dissection. Further clinical, in vivo, and histological investigation is warranted.

A technique for rigid fixation of methyl methacrylate cranioplasty: the vault-locking method.

BACKGROUND Current treatment of difficult to reach lesions of the central nervous system favors extensive bone removal for improved visualization and access with minimal brain retraction. Particularly in the posterior fossa, bone is often removed piecemeal, and a standard craniotomy flap is not always available for simple reattachment. Cranioplasty with methyl methacrylate is used to provide cosmesis and neural protection. A method for the fixation of methyl methacrylate cranioplasty is described, and the results of technique application in 30 patients during a 14-month period are reported. METHODS A series of notches are burred in the cancellous margin of the surrounding cranium, preserving the inner and outer tables. Methyl methacrylate is applied to the defect. Overflow of methyl methacrylate into the notches assures solid fixation. The resultant construct resembles the locking mechanism of a bank vault. No mesh, wire, or miniplates are required. Prolene buttresses may be placed through the outer table of the notches to identify their location, should removal of the plasty be required. Removal of the outer table over the notches facilitates rapid removal. RESULTS Solid plasty and good cosmesis occurred in all patients. There were no infections or complications related to this technique. CONCLUSIONS Firm fixation, molding and hardening in situ, and technical ease are potential advantages over established methods of cranioplasty.

Mandatory Change From Surgical Skull Caps to Bouffant Caps Among Operating Room Personnel Does Not Reduce Surgical Site Infections in Class I Surgical Cases: A Single-Center Experience With More Than 15 000 Patients

BACKGROUND Surgical site infections (SSIs) are noteworthy and costly complications. New recommendations from a national organization have urged the elimination of traditional surgeons caps (surgical skull caps) and mandated the use of bouffant caps to prevent SSIs. OBJECTIVE To report SSI rates for >15 000 class I (clean) surgical procedures 13 mo before and 13 mo after surgical skull caps were banned at a single site with 25 operating rooms. METHODS SSI data were acquired from hospital infection control monthly summary reports from January 2014 to March 2016. Based on a change in hospital policy mandating obligatory use of bouffant caps since February 2015, data were categorized into nonbouffant and bouffant groups. Monthly and cumulative infection rates for 13 mo before (7513 patients) and 13 mo after (8446 patients) the policy implementation were collected and analyzed for the groups, respectively. RESULTS An overall increase of 0.07% (0.77%-0.84%) in the cumulative rate of SSI in all class I operating room cases and of 0.03% (0.79%-0.82%) in the cumulative rate of SSI in all spinal procedures was noted. However, neither increase reached statistical significance (P > .05). The cumulative rate of SSI in neurosurgery craniotomy/craniectomy cases decreased from 0.95% to 0.75%; this was also not statistically significant (P = 1.00). CONCLUSION National efforts at improving healthcare performance are laudable but need to be evidence based. Guidelines, especially when applied in a mandatory fashion, should be assessed for effectiveness. In this large, single-center series of patients undergoing class I surgical procedures, elimination of the traditional surgeons cap did not reduce infection rates.