Factors associated with favorable response to hyperbaric oxygen therapy among patients presenting with iatrogenic cerebral arterial gas embolism.

BACKGROUND: Iatrogenic cerebral arterial gas embolism (CAGE) is an uncommon but potentially a fatal condition. Hyperbaric oxygen (HBO2) therapy is the only definitive treatment for patients with CAGE presenting with acute neurologic deficits. METHODS: We reviewed medical records and neuroimaging of consecutive CAGE patients treated with HBO2 at a state referral hyperbaric facility over a 22-year period. We analyzed the effect of demographics, source of intra-arterial gas, signs and symptoms, results of imaging studies, time between event and HBO2 treatment, and response to HBO2 treatment in 36 consecutive patients. Favorable outcome was defined by complete resolution or improvement of CAGE signs and symptoms at 24 h after HBO2 treatment. Unfavorable outcome was defined by unchanged or worsened neurologic signs and symptoms or in hospital death. RESULTS: A total of 26 (72%) of the 36 patients had favorable outcome. Patients with favorable outcome were younger compared to those with unfavorable outcome (mean age [years, SD] 44.7 ± 17.8 vs. 58.1 ± 24.1, p = 0.08). Cardiopulmonary symptoms were significantly more common in CAGE related to venous source of gas compared to arterial source (p = 0.024) but did not influence the rate of favorable outcomes. Adjusted multivariate analysis demonstrated that time from event to HBO2 ≤ 6 h (positively) and the presence of infarct/edema on head computerized tomography (CT)/magnetic resonance imaging (MRI) before HBO2 (negatively) were independent predictors of favorable outcome at 24 h after HBO2 treatment [odds ratio (OR) 9.08 confidence interval (CI) (1.13-72.69), p = 0.0376, and (OR) 0.034 (CI) (0.002-0.58), p = 0.0200, respectively]. Two of the 36 patients were treated with thrombolytics because of acute focal deficits and suspected ischemia-one with intravenous and the second with intra-arterial thrombolysis. The latter patient developed fatal intracerebral hemorrhage. CONCLUSIONS: A high proportion of CAGE patients treated with HBO2 had favorable outcomes. Time-to-HBO2 ≤ 6 h increased the odds of favorable outcome, whereas the presence of infarct/edema on CT/MRI scan before HBO2 reduced the odds of a favorable outcome. Timely diagnosis and differentiation from thrombo-embolic ischemic events appears to be an important determinant of successful HBO2 treatment.

Should children be SCUBA diving?: Cerebral arterial gas embolism in a swimming pool.

Cerebral arterial gas embolism (CAGE) is a well-known serious complication of self-contained breathing apparatus (SCUBA) diving. Most serious complications of SCUBA diving occur in adults because most of SCUBA divers are adults. However, young age is an independent risk factor for injury in SCUBA diving and shallow-water SCUBA diving is the riskiest environment for CAGE. We present a case of a 10-year-old boy who developed CAGE while taking SCUBA diving lessons in a university swimming pool. This case illustrates the potential danger of SCUBA diving for children who lack understanding of the physics of diving as well as the often unappreciated risk of shallow-water SCUBA diving. Our intent is to educate providers of primary care to children, so that they may appropriately advise parents about SCUBA diving, and to educate providers of emergency care to children, so that they will recognize this uncommon but serious emergency condition.

Hyperbaric oxygen for treatment of problem wounds.

Hyperbaric oxygen treatment has seen a resurgence of interest in recent years, with more academic medical centers building facilities and more physicians becoming board-certified in undersea and hyperbaric medicine.The reason for the growing interest is better understanding of the role of hypoxia in wound healing and an appreciation for the role of HBOT in reversing tissue hypoxia and enhancing the healing process.This has resulted in a number of new evidence-based indications for HBOT. This article describes the role of HBOT in wound healing and how it specifically applies to treatment of delayed radiation injury, one of the conditions for which it is commonly used.

Bisphosphonate-related osteonecrosis of the jaw: clinical features, risk factors, management, and treatment outcomes of 26 patients.

PURPOSE: To report the clinical features, risk factors, management, and treatment outcomes of nitrogen-containing bisphosphonate (n-BIS)-related osteonecrosis of the jaw (BRONJ). PATIENTS AND METHODS: Patients with suspected BRONJ were referred to the School of Dentistry for evaluation and treatment. RESULTS: A total of 26 patients (9 men and 17 women, mean age 64 years) were diagnosed with BRONJ. Of the 26 patients, 23 had received n-BIS therapy for cancer and 3 for osteoporosis. BRONJ lesions were noted more frequently in the mandible and in the posterior sextants. Of the 26 patients, 16 had developed BRONJ after dentoalveolar procedures, and 10 had developed it spontaneously. The mean interval to development of BRONJ was shorter in the patients with cancer receiving intravenous n-BIS than in the patients with osteoporosis receiving oral n-BIS (37.1 versus 77.7 months, P = .02). Using the American Association of Oral and Maxillofacial Surgeons staging system, 2 patients were diagnosed with stage I lesions, 19 with stage II, and 5 with stage III lesions. The initial management of BRONJ was nonsurgical, with debridement performed at subsequent visits, if needed. The BRONJ lesions healed completely in 4 patients, healed partially in 8, remained stable in 7, and progressed in 7. The spontaneous lesions responded favorably to BRONJ management compared with lesions that developed after dentoalveolar procedures (P = .01). No significant difference was found in response to BRONJ management between patients who had continued or discontinued n-BIS therapy after the BRONJ diagnosis (P = .54). CONCLUSIONS: Long-term n-BIS therapy and recent dental procedures are consistent findings in patients with BRONJ. Spontaneous BRONJ lesions respond favorably to current BRONJ treatment strategies.

Cardiovascular manifestations of moderate to severe carbon monoxide poisoning.

OBJECTIVES: We describe the cardiovascular manifestations of carbon monoxide (CO) poisoning. BACKGROUND: Carbon monoxide poisoning is a common cause of toxicologic morbidity and mortality. Although the neurologic sequelae of CO poisoning have been well described, the cardiovascular consequences are limited to isolated case reports. METHODS: We reviewed the cardiovascular manifestations of 230 consecutive patients treated for moderate to severe CO poisoning in the hyperbaric oxygen chamber at Hennepin County Medical Center (HCMC), a regional center for treatment of CO poisoning. RESULTS: The mean age was 47.2 years with 72% men. Ischemic electrocardiogram (ECG) changes were present in 30% of patients, whereas only 16% had a normal ECG. Cardiac biomarkers (creatine kinase-MB fraction or troponin I) were elevated in 35% of patients. In-hospital mortality was 5%. CONCLUSIONS: Cardiovascular sequelae of CO poisoning are frequent, with myocardial injury assessed by biomarkers or ECG in 37% of patients. Patients admitted to the hospital with CO poisoning should have a baseline ECG and serial cardiac biomarkers.

Myocardial injury and long-term mortality following moderate to severe carbon monoxide poisoning.

CONTEXT: Carbon monoxide (CO) poisoning is a common cause of toxicological morbidity and mortality. Myocardial injury is a frequent consequence of moderate to severe CO poisoning. While the in-hospital mortality for these patients is low, the long-term outcome of myocardial injury in this setting is unknown. OBJECTIVE: To determine the association between myocardial injury and long-term mortality in patients following moderate to severe CO poisoning. DESIGN, SETTING, AND PARTICIPANTS: Prospective cohort study of 230 consecutive adult patients treated for moderate to severe CO poisoning with hyperbaric oxygen and admitted to the Hennepin County Medical Center, a regional center for treatment of CO poisoning, between January 1, 1994, and January 1, 2002. Follow-up was through November 11, 2005. MAIN OUTCOME MEASURE: All-cause mortality. RESULTS: Myocardial injury (cardiac troponin I level > or =0.7 ng/mL or creatine kinase-MB level > or =5.0 ng/mL and/or diagnostic electrocardiogram changes) occurred in 85 (37%) of 230 patients. At a median follow-up of 7.6 years (range: in-hospital only to 11.8 years), there were 54 deaths (24%). Twelve of those deaths (5%) occurred in the hospital as a result of a combination of burn injury and anoxic brain injury (n = 8) or cardiac arrest and anoxic brain injury (n = 4). Among the 85 patients who sustained myocardial injury from CO poisoning, 32 (38%) eventually died compared with 22 (15%) of 145 patients who did not sustain myocardial injury (adjusted hazard ratio, 2.1; 95% confidence interval, 1.2-3.7; P = .009). CONCLUSION: Myocardial injury occurs frequently in patients hospitalized for moderate to severe CO poisoning and is a significant predictor of mortality.

Hyperbaric oxygen therapy: a meeting place for medicine and dentistry.

The hyperbaric medicine facility at Hennepin County Medical Center has been serving patients from throughout the region for more than 40 years. Some of these patients have head and neck cancer and are suffering delayed complications of radiation therapy. Such patients are often referred by dentists, oral surgeons, and otolaryngologists. This article summarizes outcomes for patients who have received hyperbaric oxygen therapy for 3 conditions: soft-tissue radiation injury before undergoing dental extractions, osteoradionecrosis, and soft-tissue radiation injury prior to receiving dental implants in the irradiated area.