Outcomes of abdominal aortic aneurysm repairs: Endovascular vs open surgical repairs.

BACKGROUND: Operative mortality after endovascular aneurysm repair (EVAR) has been reported as lower than open surgical repair (OSR) for abdominal aortic aneurysm (AAA) in randomized controlled trials. However, many cohort studies have demonstrated similar mortality rates for both procedures. We compared operative mortality between EVAR and OSR, at our institution. METHODS: All AAA operations from 2012 to 2017 were reviewed, and baseline characteristics were collected. Outcomes included 30-day mortality, operative data, complications, length of hospital stay (LOS), costs, re-intervention, and survival rates were compared. A multivariable analysis with unbalanced characteristics was performed. RESULTS: We had a total of 162 patients, 100 having OSR and 62 for EVAR. The EVAR group was older, with higher ASA classification. Thirty-day mortality rate did not significantly differ (0/100 for OSR and 2/62 (3%) for EVAR; p = 0.145), while the EVAR group had less blood loss, shorter operative times, and LOS, but higher re-intervention rates (adjusted hazard ratio 6.4 (95%CI: 1.4, 26.8)). Survival rates did not significantly differ between the groups. EVAR cost approximately 1-million yen more. CONCLUSIONS: OSR had low 30-day mortality rate in selected low-risk patients whereas EVAR had less blood loss, shorter operative times, LOS and could be done in high-risk patients with low 30-day mortality but with higher re-intervention rate.

Preventive Effects of Sustainable and Developmental Perioperative Oral Management Using the "Oral Triage" System on Postoperative Pneumonia after Cancer Surgery.

Perioperative oral management is widely recognized in the healthcare system of Japan. Conventionally, the surgeon refers patients with oral problems to a dental or oral surgery clinic in the hospital. However, frequent in-house referrals were found to increase the number of incoming patients resulting in unsustainable situations due to an insufficient workforce. In 2011, the Center for Perioperative Medicine was established at our hospital to function as a management gateway for patients scheduled to undergo surgery under general anesthesia. The "oral triage" system, wherein a dental hygienist conducts an oral screening to select patients who need preoperative oral hygiene and functional management, was established in 2012. A total of 37,557 patients who underwent surgery at our hospital from April 2010 to March 2019 (two years before and seven years after introducing the system) were evaluated in this study. The sustainability and effectiveness of introducing the system were examined in 7715 cancer surgery patients. An oral management intervention rate of 20% and a significant decrease in the incidence of postoperative pneumonia (aOR = 0.50, p = 0.03) indicated that this system could be useful as a sustainable and developmental oral management strategy to manage surgical patients with minimal human resources.

A novel method of vein cuff creation for below-knee femoropopliteal bypass with a prosthetic graft.

Vein cuff anastomosis is beneficial in cases in which a prosthetic graft is anastomosed to a small and thickened peripheral artery. Various types of vein cuff are currently in use, although their design is insufficient when a size discrepancy exists between the two vessels and the angle of anastomosis requires adjustment. We report a case of a patient who underwent below-knee femoropopliteal bypass using a new design of vein cuff (boat-form vein cuff) that increases the ease of cuff creation and enables surgeons to adjust the anastomotic size and angle.

Mitral valve replacement and trans-mitral myectomy for a child with Noonan syndrome accompanied by hypertrophic obstructive cardiomyopathy.

A 4-year-old boy with Noonan syndrome accompanied by hypertrophic obstructive cardiomyopathy presented with refractory heart failure owing to severe left ventricular outflow obstruction and mitral regurgitation. He underwent mitral valve replacement and trans-mitral myectomy. The pathology of the resected myocardium was consistent with hypertrophic cardiomyopathy, and the mitral valve leaflets were severely degenerated. Compared with a control patient who is a non-syndromic 4-year-old boy with hypertrophic obstructive cardiomyopathy, mitral pathology was much more severe in Noonan syndrome. Regarding trans-mitral myectomy, residual pressure gradient at the mid-ventricular level made us think about more aggressive muscle resection with various approaches.

Glucose metabolism changes during the development and progression of oral tongue squamous cell carcinomas.

Previous studies have revealed several genes involved in the carcinogenesis of oral cancer. However, the detailed mechanisms underlying this process are poorly understood. Previously, we established a database cataloging the transcriptional progression profile of oral carcinogenesis and identified several candidate genes with continuously increasing or decreasing expression, which specifically promote the transition of oral premalignant lesions to invasive carcinomas. In this study, using our microarray database, we attempted to determine significant genes that may contribute to metabolic alterations during oral carcinogenesis. After performing a literature survey, we focused on 15 candidate genes associated with glucose metabolism changes, particularly the tri-carboxylic acid cycle, and investigated the mRNA-expression status of these genes with our database. Only the solute carrier family 2 member 1 gene (also known as GLUT1), showed significantly increased mRNA expression during oral tumorigenesis. Immunohistochemical analysis confirmed that GLUT1 protein expression significantly increased during oral carcinogenesis. In addition, tumors with high expression of this protein significantly correlated with nodal status (P=0.002). Kaplan-Meier survival curves clearly demonstrated the adverse impact of high GLUT1 protein expression on disease-free survival (P=0.004). GLUT1 mRNA and protein expression increased in the order of normal mucosal tissues, epithelial dysplastic lesions and invasive carcinomas. Therefore, metabolic alterations, especially in glucose metabolism, occurred at the very early stage of development of oral malignancies. In addition, GLUT1 played a significant role in oral cancer, acquiring a malignant phenotype.

Characterizing Genetic Transitions of Copy Number Alterations and Allelic Imbalances in Oral Tongue Carcinoma Metastasis.

Primary tumor (PT) heterogeneity can significantly affect the genetic profile of clones at metastatic sites. To understand the mechanisms underlying metastasis, we compared the genetic profile of paired PT and metastatic lymph node (MLN) samples obtained from patients with oral tongue squamous cell carcinoma (OTSCC). Large-scale genetic profiling was performed on paired PT-MLN samples obtained from 10 OTSCC patients using high-density single-nucleotide polymorphism microarrays. We compared the genetic profile of PT and MLN OTSCC samples to identify common and specific copy number alterations and copy-neutral loss-of-heterozygosity (CN-LOH). Unsupervised hierarchical clustering analysis indicated that 8 of the 10 PT-MLN sample pairs formed clusters, indicating that the primary and metastatic tumors were composed of predominantly genetically similar tumor cells. In 6 of the 10 pairs, 8q11.21, 8q12.2-3, and 8q21.3 gains, and 22q11.23 loss were detected in both the PT and MLN. In addition, 16p11.2 CN-LOH was identified in 9 of the 10 pairs. Conversely, 20q11.2 gain was only observed in the MLNs of 5 of the 10 sample pairs, indicating that genes in this chromosomal region may play a significant role in OTSCC lymph node metastasis. To confirm this, we investigated the expression of two candidate 20q11.2 genes in a separate patient cohort. The expression of one of these genes, E2F1, was significantly increased during the process of metastasis. This study indicates that additional genetic changes, such as 20q11.2 gain, which encodes the E2F1 gene, can be acquired through clonal evolution, and may be required for the metastatic process. © 2016 Wiley Periodicals, Inc.

Prognostic factors affecting early colectomy in patients with moderate to severe ulcerative colitis treated with calcineurin inhibitors.

Calcineurin inhibitors (CNIs) such as cyclosporine A (CSA) and tacrolimus (FK506) are often used as a second-line drug for steroid-refractory or steroid-dependent patients with ulcerative colitis (UC). The aim of the present study was to determine the prognostic factors for early colectomy. A total of 85 hospitalized patients with UC (CSA, 50 patients; FK506, 35 patients) were enrolled. Colectomy carried out within 60 days of starting CNI therapy was defined as 'early colectomy'. To assess the prognostic factors affecting early colectomy, clinical practical variables, including the Onodera-prognostic nutritional index (O-PNI): 10xAlb+0.005× (total lymphocyte count), were analyzed. The results demonstrated that the significant factors predicting early colectomy were i) disease severity, ii) immunomodulator-naïve history, iii) lower serum hematocrit, iv) lower serum albumin and v) lower O-PNI. In addition, the significant factors predicting overall colectomy were as follows: i) C7-HRP positivity and ii) >10,000 mg of prednisolone used prior to the initiation of CNI treatment. The combination of hematocrit and O-PNI enhanced the prediction of early colectomy. Clinical variables such as hematocrit and O-PNI were the significant factors predicting colectomy. These results may be used as a guide to predict the outcome of patients with UC in clinical settings.

The high-temperature requirement factor A3 (HtrA3) is associated with acquisition of the invasive phenotype in oral squamous cell carcinoma cells.

OBJECTIVES: Previous studies have identified several genes involved in the carcinogenesis of oral cancer; however, the detailed mechanisms underlying this process have not been elucidated. Previously, we established a database of the transcriptional progression profile of oral carcinogenesis and identified 15 candidate genes with continuously increasing or decreasing expression (Sumino et al., 2013). MATERIALS AND METHODS: In the present study, using this database, we attempted to identify genes that may specifically contribute to progression from oral dysplastic lesions to invasive tumours. RESULTS: We identified 4 candidate genes. Using a literature survey, we narrowed down the candidates and focused on the high-temperature requirement factor A3 (HtrA3). Quantitative real-time reverse transcription polymerase chain reaction and immunohistochemical analysis confirmed that HtrA3 expression significantly increased during this process. In addition, high HtrA3 expression was significantly associated with decreased disease-free survival (P=0.045) and overall survival (P=0.003). Multivariate Cox proportional hazards analysis found that high HtrA3 expression significantly correlated with overall survival (P=0.018). CONCLUSION: The findings of this study demonstrated that the HtrA3 is likely to be associated with the acquisition of the invasive phenotype in oral squamous cell carcinoma cells and may be a potential prognostic marker for oral cancer.

The successful management of respiratory complications with long-term, low-dose macrolide administration in pediatric heart transplant recipients.

We report three pediatric heart transplant (HTx) patients whose respiratory symptoms were successfully controlled with long-term, low-dose macrolide administration (clarithromycin: CAM; approximately 2.5 mg/kg bid). The first case was an 18-year-old boy who underwent HTx at the age of three for dilated cardiomyopathy (DCM). Beginning at age 5, he had repeated fevers and respiratory symptoms. He was diagnosed with chronic sinusitis at age 11 and sinobronchial syndrome with mild bronchiectasis at age 14. Administration of long-term, low-dose CAM and otolaryngeal topical therapy led to significant improvement of his symptoms. The second case was a 7-year-old boy who underwent HTx for DCM at age one. Starting at age 4, he had repeated fevers and cough due to atelectasis and pneumonia. As antibiotics and respiratory physical therapy proved ineffective, he received long-term, low-dose CAM, resulting in successful control of his atelectasis and recurrent pneumonia. The third case was a 13-year-old boy who underwent HTx at age 6 for DCM. He had chronic sinusitis starting at age 7, and was diagnosed with obstructive sleep apnea syndrome at age 10. Adenotonsillectomy and continuous positive airway pressure support therapy were indicated. At age 13, long-term, lowdose CAM administration was started following mycoplasma infection. In all three cases, the levels of calcineurin inhibitors (cyclosporine and tacrolimus) and everolimus were kept in the optimal range with careful drug monitoring. Longterm, low-dose macrolide administration effectively prevents and treats respiratory complications in pediatric HTx patients as long as attention is paid to potential drug interactions.

Gene expression changes in initiation and progression of oral squamous cell carcinomas revealed by laser microdissection and oligonucleotide microarray analysis.

Oral carcinogenesis is a complex process involving multiple genes. However, the genetic changes involved in this process are not apparent in identical oral squamous cell carcinomas (OSCCs). According to pathological characteristics, samples of normal tissue, oral dysplastic lesions (ODLs), and invasive cancers were obtained from identical OSCCs using laser microdissection (LMD). Large-scale gene expression profiling was carried out on 33 samples derived from 11 OSCCs. We analyzed genes differentially expressed in normal tissues vs. ODLs and in ODLs vs. invasive tumors and identified 15 candidate genes with continuously increasing or decreasing expression during oral carcinogenesis. One of these genes, ISG15, was chosen for further characterization. Real-time quantitative reverse transcription-polymerase chain reaction and immunohistochemical analysis confirmed that ISG15 expression consistently increased during oral tumorigenesis. An ISG15 high-expression level was significantly associated with poor prognosis (p = 0.027). In addition, patients with high-expression tumors had a poorer 5-year survival rate than patients with low expression levels (p = 0.019). In conclusion, we identified 15 genes with continuously increasing or decreasing expression during oral carcinogenesis. One of these, ISG15, is likely to be associated with both dysgenesis and tumorigenesis and may be a potential prognostic marker for oral cancer.

Loss of NKX3-1 as a potential marker for an increased risk of occult lymph node metastasis and poor prognosis in oral squamous cell carcinoma.

The prognosis of oral squamous cell carcinoma (OSCC) is significantly dependent on the existence of cervical lymph node metastasis (LNM), with the overall survival rate being much lower in patients with LNM. Primary causes and molecular mechanisms of LNM are still largely unclear. We hypothesized that factors related with cancer progress and/or prognosis in OSCC are revealed by genome-wide investigation of DNA copy number aberrations (CNAs). In order to find biomarkers for occult LNM of OSCC, we comprehensively investigated genomic DNAs from 60 OSCC patients using Affymetrix mapping arrays and statistically analyzed correlations between CNAs of genes and the presence of occult LNM in the patients. The genome-wide CNA study indicated significant correlations between the presence of occult LNM and CNAs of certain genes. Through a literature survey, we narrowed down the candidates and focused on loss of NKX3-1, which is a homeodomain-containing transcription factor. NKX3-1 is known as a tumor suppressor gene in prostate cancer but has never been reported in OSCC. Quantitative RT-PCR and immunohistochemistry (IHC) analyses also showed significantly lower expression of NKX3-1 in the cases with occult LNM, which was further validated by IHC analysis in independent cases. The survival analyses indicated that NKX3-1 loss is a significant risk factor to decrease the disease-free survival (DFS) and the overall survival (OS) rates. This is the first time that the significant association of NKX3-1 loss and occult LNM was indicated in OSCC. The present results suggest that loss of NKX3-1 may be a potential biomarker for occult LNM of OSCC.

EGFR gene copy number alteration is a better prognostic indicator than protein overexpression in oral tongue squamous cell carcinomas.

Although epidermal growth factor receptor (EGFR) is particularly important in the pathogenesis of head and neck squamous cell carcinomas (HNSCCs), conflicting data have been reported on the correlation between EGFR copy number and survival and the association between EGFR copy number and protein expression. Anatomical site of the tumour in HNSCCs may likely contribute to the discordance of the above points as EGFR expression may differ between the sub-sites of HNSCCs. Thus, in this study, we focused on oral tongue squamous cell carcinomas (OTSCCs). To investigate the association between EGFR copy number alteration and overexpression and to determine which is the more reliable prognostic indicator, Fluorescence in situ hybridisation (FISH) and immunohistochemical staining (IHC) were performed at a single institution on samples from 89 patients with OTSCCs undergoing surgery as the primary treatment modality. Thirty-two (36%) of 89 cases demonstrated an EGFR copy number alteration. EGFR protein expression was found in all 89 cases, of which 82.0% showed overexpression. No significant correlation was found between gene copy number and protein overexpression. Gene copy number alteration was significantly associated with reduced disease-free survival (P=0.048) and overall survival (P=0.001). Multivariate Cox proportional hazards analysis demonstrated that EGFR copy number increase was significantly correlated with overall survival (P=0.001). EGFR copy number status is a more reliable indicator than protein overexpression of the survival rate in OTSCCs. FISH analysis of the EGFR status is useful in predicting poor prognosis in OTSCCs.

Prognostic utility of chromosomal instability detected by fluorescence in situ hybridization in fine-needle aspirates from oral squamous cell carcinomas.

BACKGROUND: Although chromosomal instability (CIN) has been detected in many kinds of human malignancies by means of various methods, there is no practical assessment for small clinical specimens. In this study, we evaluated CIN in fine-needle aspiration (FNA) biopsied oral squamous cell carcinomas (SCCs) using fluorescence in situ hybridization (FISH) analysis, and investigated its prognostic significance. METHODS: To evaluate CIN status of tumors, FISH with genomic probes for the centromeres of chromosomes 7, 9, and 11 was performed on specimens obtained by FNA from 77 patients with primary oral SCCs. RESULTS: High-grade CIN (CIN3) was observed in 11.7% (9/77) of patients with oral SCCs and was associated significantly with reduced disease-free survival (p = .008) and overall survival (p = .003). Multivariate Cox proportional hazards analysis showed that CIN status was significantly correlated with disease-free survival (p = .035) and overall survival (p = .041). CONCLUSION: Analysis of CIN status using FISH on FNA biopsy specimens may be useful in predicting of recurrence and poor prognosis in patients with oral SCCs.

The comparative effects of sevoflurane versus isoflurane on cerebrovascular carbon dioxide reactivity in patients with previous stroke.

PURPOSE: The use of volatile anesthetics is reportedly related to altered cerebrovascular carbon dioxide (CO2) reactivity. We examined the comparative effects of sevoflurane versus isoflurane on cerebrovascular CO2 reactivity in patients with previous stroke. METHODS: Twenty-four patients with previous stroke and 20 patients without previous stroke (serving as controls) were studied. Anesthesia was maintained with either end-tidal 1.0 minimum alveolar concentration (MAC) sevoflurane or 1.0 MAC isoflurane in 33% oxygen and 67% nitrous oxide. A 2.5-MHz pulsed transcranial Doppler (TCD) probe was attached to the patient's head at the right or left temporal window for continuous measurement of mean blood flow velocity in the middle cerebral artery (Vmca). After establishing baseline values of Vmca and cardiovascular hemodynamics, we increased end-tidal CO2 by decreasing the ventilatory frequency by 2-5 breaths x min(-1). RESULTS: We found that values for absolute and relative CO2 reactivity in the sevoflurane groups were lower than those in the isoflurane groups (absolute CO2 reactivity in the sevoflurane groups: control, 3.3 +/- 0.4*; previous stroke, 3.4 +/- 0.4*; absolute CO2 reactivity in the isoflurane groups: control, 4.2 +/- 0.3; previous stroke, 4.5 +/- 0.4, cm x s(-1) x mmHg(-1); *P < 0.05 compared with isoflurane group). There were no significant differences in the values for absolute and relative CO2 reactivity between the controls and the previous-stroke patients within each of the sevoflurane and isoflurane groups. CONCLUSION: Our findings suggest that, in patients with previous stroke, cerebrovascular CO2 reactivity under sevoflurane anesthesia was lower than that under isoflurane anesthesia.

Fluorescence in situ hybridization for detecting genomic alterations of cyclin D1 and p16 in oral squamous cell carcinomas.

BACKGROUND: Cyclin D1 (CCND1) and p16 alterations have been detected in oral squamous cell carcinomas (SCCs), suggesting that abnormalities of these genes may play an important role in the genesis or progression of oral SCCs and serve as independent prognostic indicators. The detection of CCND1 and p16 aberrations using a simple and sensitive method would be valuable for the development of effective treatment modalities for oral cancer. The objective of the current study was to determine whether CCND1 numerical aberrations and p16 deletions in oral SCCs detected by fluorescence in situ hybridization (FISH) have any impact on clinical outcome. METHODS: Using genomic DNA probes for CCND1 and p16, FISH was performed on specimens that were obtained by fine-needle aspiration (FNA) from 57 primary oral SCCs. RESULTS: The CCND1 numerical aberration was observed in 28 of 57 patients (49%) with oral SCCs and was associated significantly with reduced disease-free survival (P = .0004) and overall survival (P = .0179). Conversely, p16 deletion was detected in 22 of 57 patients (39%). The disease-free and overall survival rates for patients with p16 deletion were lower than those among patients without the p16 deletion, although the difference just failed to reach statistical significance (P = .0516 and P = .1878, respectively). The p16 deletion in the presence of the CCND1 numerical aberration conferred significantly worse disease-free survival (P = .0002) and overall survival (P = .0153). CONCLUSIONS: Although the CCND1 numerical aberration was a good predictor of aggressive tumors, recurrence, and poor prognosis in patients with oral SCCs, the authors were able to identify subgroups of patients that had early disease recurrence and a poor prognosis more efficiently by assessment of p16 deletion in addition to CCND1 genetic status using FISH on FNA biopsy samples compared with the analysis of either alteration alone.

Effects of antihypertensive medication on left ventricular function during electroconvulsive therapy: study with transthoracic echocardiography.

STUDY OBJECTIVE: To characterize the effects of antihypertensive medications on cardiac function using transthoracic echocardiography during electroconvulsive therapy (ECT). STUDY DESIGN: Randomized, double-blind study set at a university hospital. PATIENTS: 30 American Society of Anesthesiologists (ASA) physical status I and II patients undergoing ECT. INTERVENTIONS: Patients were given thiopental sodium (two mg/kg) and succinylcholine (one mg/kg), and mask ventilation was initiated with 100% oxygen before bilateral ECT. Patients received a bolus injection of one of several different antihypertensive medications: 0.08 mg/kg alprenolol, 0.01 mg/kg nitroglycerin, 0.02 mg/kg nicardipine, or saline immediately after anesthesia induction and before electrical shock. MEASUREMENTS: Cardiac function was examined through transthoracic echocardiography before anesthesia induction, throughout the ECT procedure, and for 10 minutes after the seizure. MAIN RESULTS: Electrical shock resulted in a significant change in fractional area change when compared with the awake condition. Further fractional area change at one minute after ECT was significantly higher in patients who received nicardipine than in the other groups (means +/- SD): control group, 43% +/- 10%; nitroglycerin group, 46% +/- 8%; nicardipine group, 65% +/- 6% (P < 0.05 vs the other three groups); and alprenolol group, 51% +/- 7%. Systolic blood pressure/end-systolic area-end-diastolic area at one minute after the electrical shock was higher in the control, nitroglycerin, and alprenolol groups but not in the nicardipine group when compared with the awake condition (means +/- SD): control group, 39 +/- 8 mmHg/cm(2) (P < 0.05 vs the other three groups); nitroglycerin group, 32 +/- 9 mmHg/cm(2); nicardipine group, 29 +/- 7 mmHg/cm(2); alprenolol group, 31 +/- 6 mmHg/cm(2). CONCLUSIONS: Specific antihypertensive drugs produced different hemodynamic effects during ECT. Our data suggest that alprenolol was the most appropriate agent for minimization of changes in heart rate and transthoracic echocardiographic variables after ECT.

The comparative effects of sevoflurane versus isoflurane on cerebrovascular carbon dioxide reactivity in patients with diabetes mellitus.

The use of volatile anesthetics has been reported to alter cerebrovascular carbon dioxide (CO2) reactivity. We examined the comparative effects of sevoflurane versus isoflurane on cerebrovascular CO2 reactivity in 40 patients with diabetes mellitus. Anesthesia was maintained with either 1.0 minimum alveolar anesthetic concentration of sevoflurane or 1.0 minimum alveolar anesthetic concentration of isoflurane in 33% oxygen and 67% nitrous oxide. A 2.5-MHz pulsed transcranial Doppler probe was attached to the patient's head at the right temporal window for continuous measurement of mean blood flow velocity in the middle cerebral artery. After establishing baseline middle cerebral artery velocity values and cardiovascular hemodynamics, we increased end-tidal CO2 by decreasing ventilatory frequency by 2-5 breaths/min and repeated the measurements. These were then used to calculate absolute and relative CO2 reactivity. Absolute CO2 reactivity was less in insulin-treated patients with either sevoflurane or isoflurane compared with those patients on oral antidiabetic drugs or dietary therapy (sevoflurane group: diet = 2.6 +/- 0.6; oral antidiabetic drug = 2.5 +/- 0.8; insulin = 1.6 +/- 0.8*; isoflurane group: diet = 3.3 +/- i0.7; oral antidiabetic drug = 3.4 +/- 0.7; insulin = 1.9 +/- 0.7* cm.s(-1).mm Hg(-1); *P < 0.05, respectively). Relative CO2 reactivity showed a similar pattern in the diet-controlled and oral antidiabetic groups, absolute and relative CO2 reactivities were lower with sevoflurane versus isoflurane. Hence, we conclude that cerebrovascular CO2 reactivity in insulin-dependent patients is impaired under both sevoflurane and isoflurane anesthesia.

Differential effects of propofol on cerebrovascular carbon dioxide reactivity in elderly versus young subjects.

STUDY OBJECTIVE: To examine the age-related difference between elderly and young patients in the effect of propofol on cerebrovascular carbon dioxide (CO(2)) reactivity. DESIGN: Prospective controlled study. SETTING: University hospital. PATIENTS: Elderly (older than 70 years, n = 13) and young patients (younger than 25 years, n = 13) scheduled for elective orthopedic surgery. INTERVENTIONS: After induction of anesthesia, a 2.5-MHz pulsed transcranial Doppler probe was attached to the patient's head at the right temporal window, from which mean blood flow velocity of the middle cerebral artery was measured continuously. MEASUREMENTS: After obtaining baseline values of velocity of the middle cerebral artery, arterial blood gases, and cardiovascular hemodynamics, end-tidal CO(2) was decreased by increasing the ventilatory frequency by 2 to 5 breaths per minute. Measurements were repeated when end-tidal CO(2) decreased and remained stable for 5 to 10 minutes. Cerebrovascular CO(2) reactivity, at propofol doses of 5 and 10 mg/kg/h, was measured. MAIN RESULTS: No significant differences were observed between the 2 groups in baseline absolute and relative CO(2) reactivity. However, there were significant differences between the 2 groups in absolute or relative CO(2) reactivity at a propofol dosage of 5 mg/kg/h. (Absolute CO(2) reactivity in young patients: 2.1 +/- 0.8 cm/s/mm Hg; elderly: 1.6 +/- 0.4* cm/s/mm Hg. Relative CO(2) reactivity in young patients: 7.4% +/- 1.6%/mm Hg; in the elderly: 6.5% +/- 0.9%*/mm Hg; unpaired t test, *P < .05). In contrast, there were no significant differences between the 2 groups in terms of absolute or relative CO(2) reactivity at a propofol dosage of 10 mg/kg/h. CONCLUSIONS: Cerebrovascular CO(2) reactivity in elderly patients was lower than that in young patients at a propofol dosage of 5 mg/kg/h.

Cerebrovascular carbon dioxide reactivity with propofol anesthesia in patients with previous stroke.

STUDY OBJECTIVE: To examine whether patients with previous stroke have impaired cerebrovascular carbon dioxide (CO2) reactivity when receiving propofol anesthesia. DESIGN: Prospective, controlled study. SETTING: University hospital. PATIENTS: 34 consecutive patients, 17 of whom had previous stroke and were scheduled for elective cardiac surgery, and 17 control age-matched patients without previous stroke who were also scheduled for cardiac surgery. INTERVENTIONS: Anesthesia was induced and a 2.5-MHz pulsed transcranial Doppler probe was attached to the patient's head at the right temporal window. Mean blood flow velocity of the middle cerebral artery (Vmca) was measured continuously. MEASUREMENTS: After establishing baseline Vmca, arterial blood gases and cardiovascular hemodynamic values, partial pressure of end-tidal CO2 (PETCO2) was increased by changing the ventilatory frequency by 2 to 5 breaths/min. The measurements were repeated when PETCO2 increased and remained stable for 5 to 10 minutes. MAIN RESULTS: Values for absolute CO2 reactivity in the control patients and in those with previous stroke were 2.6 +/- 0.5 and 2.9 +/- 0.7 cm/sec/mmHg, respectively, a nonsignificant difference in these values. Values for relative CO2 reactivity in control patients and in patients with previous stroke were 6.4 +/- 1.4 and 6.1 +/- 1.4%/mmHg, respectively, with no significant difference noted. CONCLUSIONS: Cerebrovascular CO2 reactivity in patients with previous stroke is normal during propofol anesthesia.