The value of transcranial Doppler sonography with a transorbital approach in the confirmation of cerebral circulatory arrest.

OBJECTIVE: Transcranial Doppler sonography (TCD) provides accurate confirmation of cerebral circulatory arrest (CCA) in brain death (BD), but is not feasible in patients with absent temporal bone windows. We added the transorbital approach in the TCD protocol for the diagnosis of CCA and compared findings with angiography. Furthermore, we evaluated whether reporting the angiographic and sonographic confirmation of CCA to relatives of brain-dead patients improves their comprehension and satisfaction with the medical information. PATIENTS AND METHODS: Eighty-two clinically brain-dead patients underwent 4-vessel angiography, TCD of the basilar and middle cerebral arteries, and transorbital Doppler sonography (TOD) of the internal carotid arteries. Relatives were randomly allocated to 41 in whom BD was presented as a clinical diagnosis (group A) and to 41 in whom BD was presented as a clinical diagnosis confirmed by TCD and angiography (group B). Comprehension and satisfaction of the relatives were assessed using an interview and a questionnaire. RESULTS: Both angiography and TCD verified CCA in all cases (k = 1). In 11 patients with failure of the transtemporal approach, CCA was confirmed by the transorbital recordings. The addition of TOD enabled 15.5% more cases of CCA to be diagnosed by TCD. Group B exhibited improved comprehension and satisfaction rates (P < .05). CONCLUSIONS: The addition of TOD increases the efficacy of TCD in confirming CCA in BD. Reporting confirmation of CCA to families of brain-dead patients may improve their comprehension and satisfaction with the provided medical information.

Cardiovascular ultrasound in detecting central venous catheter thrombosis in the intensive care unit: splenectomy and antiphospholipid syndrome.

Venous thrombosis of the upper extremities is becoming increasingly prevalent in the intensive care unit as a result of chronic in-dwelling central venous catheters. We report two rare cases in which combined transoesophageal echocardiography and vascular ultrasound examination aided in the identification of catheter-related thrombosis in two patients suffering from splenectomy-induced thrombocytosis and antiphospholipid syndrome respectively.

Candidemia in immunocompromised and immunocompetent critically ill patients: a prospective comparative study.

The purpose of this study was to compare the risk factors, clinical manifestations, and outcome of candidemia in immunocompromised (IC) and nonimmunocompromised (NIC) critically ill patients. Data were collected prospectively over a 2-year period (02/2000-01/2002) from patients in a 25-bed, medical-surgical intensive care unit (ICU). Eligible for participation in this study were patients who developed candidemia during their ICU stay. Patients under antifungal therapy and with a confirmed systemic fungal infection prior to the diagnosis of candidemia were excluded. Cultures of blood, urine, and stool were performed for all patients in the study, and all patients underwent endoscopy/biopsy of the esophagus for detection of Candida. Smears and/or scrapings of oropharyngeal and esophageal lesions were examined for hyphae and/or pseudohyphae and were also cultured for yeasts. During the study period, 1,627 patients were hospitalized in the ICU, 57% for primary medical reasons and 43% for surgical reasons. After application of the study's inclusion and exclusion criteria, 24 patients with candidemia (9 IC and 15 NIC) were analyzed. Total parenteral nutrition was more common in IC than in NIC patients (9/9 [100%] vs 8/15 [53%], p = 0.02). Oropharyngeal candidiasis was detected in 5 of 9 (55.5%) IC patients and in 1 of 15 (6.5%) NIC patients (p = 0.015). Esophageal candidiasis was also more common in IC than in NIC patients (4/9 [44%] vs 0/15 [0%], p = 0.012). Among the 9 IC patients, all except 2 died, resulting in a crude mortality of 78%; among the 15 NIC patients, 9 died, resulting in a crude mortality of 60% (p > 0.05). Autopsy was performed in two IC and in six NIC patients, with disseminated candidiasis found in one IC patient. Oropharyngeal and esophageal candidiasis are frequent in IC patients with candidemia. In contrast, this coexistence is rare in NIC critically ill patients with Candida bloodstream infections. A high mortality was noted in both IC and NIC critically ill patients with candidemia.

Candiduria in critically ill patients: an early candidemia marker when coupled with multiple blood specimens PCR assays?

BACKGROUND/AIMS: Can repeated blood PCR assays in critically ill patients with culture-confirmed candiduria help in the early detection of candidemia? METHODOLOGY: Urine samples were obtained on the day of admission and if negative were repeated on the 5th ICU day. Upon laboratory confirmation of candiduria, preemptive antifungal therapy was commenced. Whole blood samples were tested simultaneously with conventional cultures and PCR repeated twice weekly for two weeks. RESULTS: In ICU patients with candiduria, preemptive antifungal therapy resulted in candiduria clearance and clinical improvement in 94% of them. Candida DNAemia (detected in 64 out of 136 repeated PCR assays) persisted for 1 or 2 weeks in a significant number of patients. Even after multiple positive PCR assays from each individual candiduric patient, the specificity and positive predictive value of the assay in the early detection of candidemia were low (negative predictive value was 100%). No differences were detected on demographics among patients with or without candiduria. The correlations (PCR with culture) with kappa test presented a poor agreement (K = 0.103, Kmin= -0679, Kmax = 0.103). CONCLUSIONS: PCR in the blood should not be used in early diagnosis of (but it could help in excluding) candidemia, in ICU patients with candiduria.

Post-surgical meningitis due to multiresistant Acinetobacter baumannii. Effective treatment with intravenous and/or intraventricular colistin and therapeutic dilemmas.

Post-surgical meningitis and/or ventriculitis caused by Gram-negative bacteria may be difficult to treat due to the emergence of multiresistant strains. Two patients with multiresistant Acinetobacter baumannii central nervous system infection, successfully treated with either intravenous and/or intraventricular colistin are presented. Unresolved issues such as dose and duration of intraventricular colistin are discussed.

In vitro binding of lidocaine to liver tissue under the influence of propranolol: another mechanism of interaction?

The co-administration of lidocaine and propranolol leads to significant drug-drug interactions. Beta-blockers decrease liver perfusion and inhibit the activity of hepatic microsomal lidocaine metabolizing enzymes of the P450_2D subfamily. Hence, there is a resulting reduction in the hepatic breakdown of lidocaine and an increase in its serum concentrations. In this study the ability of propranolol to displace lidocaine from its binding sites in liver tissue has been examined through an in vitro model. Rat liver slices were incubated together with propranolol and/or lidocaine in human serum and the percentage of the bound fraction of lidocaine in the experimental mixture was assessed. The present results indicate that propranolol significantly decreases the binding process of lidocaine in liver tissue. This effect develops only when blood is used as incubation medium and the incubation period lasts 60 min. In conclusion, propranolol can displace lidocaine from liver proteins and therefore the co-administration of the two drugs may increase the free fraction of lidocaine excreted by the liver. However, this result arises from an in virro model and thus further investigation is needed.

Transorbital sonographic monitoring of optic nerve diameter in patients with severe brain injury.

OBJECTIVE: We investigated whether alterations in the optic nerve diameter (OND) correlated with brain computed tomography (CT) imaging results among patients with brain injury and whether monitoring of OND could predict brain death. PATIENTS AND METHODS: We enrolled 54 patients with brain injury (Glasgow Coma Scale < 8) and 53 controls. OND measurements were performed 3 mm posterior to the papillae by means of transorbital sonography. The severity of the injury was classified according to a semiquantitative CT neuroimaging scale (1 to 4). All patients underwent 3 repeated evaluations of OND combined with synchronous CT scans. RESULTS: Twenty-two patients progressed to brain death, while 32 patients showed gradual clinical improvement. Upon admission, the patients showed significantly increased OND (4.84 +/- 1.2 mm) compared with the controls (3.49 +/- 1.1 mm; P < .001). The median intraobserver variation of OND was 0.2 mm (95% confidence intervals [CI]: 0.1-0.7). The median interobserver variation of OND was 0.3 mm (95% CI: 0.1-0.9). Alterations in the OND were significantly correlated with the neuroimaging scale on 3 repeated evaluations: r = .65, r = .70, and r = .73 (all P < .001). An OND greater than 5.9 mm (specificity = 65% and sensitivity = 74%; P < .01) and a 2.5 mm increased OND between repeated measurements (specificity = 70% and sensitivity = 81%; P < .01) were associated with a poor prognosis. CONCLUSIONS: Alterations in OND strongly correlated with neuroimaging results among patients with brain injury. However, monitoring of OND exhibited a low predictive value for brain death.