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A Maslow

Publications and source records attributed to A Maslow.

11 recordsLinked to original sources
PubMed2001

Monitoring end-tidal carbon dioxide during weaning from cardiopulmonary bypass in patients without significant lung disease.

End-tidal carbon dioxide tension (PETCO(2)) changes with fluctuations in cardiac output (CO). We compared PETCO(2) to pulmonary artery blood flow (PAQt) during weaning from cardiopulmonary bypass (CPB) in normothermic patients without significant pulmonary disease. Fifteen consecutive adult cardiac surgical patients were prospectively studied during and shortly after weaning from CPB. Before separation from CPB, PETCO(2) and PAQt were measured, the latter by transesophageal Doppler echocardiography. At the time of measurements patients were normothermic, and ventilated at 6 breaths/min with tidal volumes of 10 mL/kg. After separation from CPB, thermodilution cardiac output (TDCO) was measured in addition to PAQt and PETCO(2). Regression and bias analyses were used to compare PETCO(2), PAQt, and TDCO. Seventy measurements were recorded; 31 before separation from CPB and 39 after separation from CPB. A good correlation was seen between PAQt and PETCO(2) (r = 0.88) and between TDCO and PAQt (r = 0.93; mean bias 0.03 L/min; SD 0.52 L/min). The regression analysis of PAQt on PETCO(2) showed greater variability at PETCO(2) levels > 34 mm Hg (n = 22; r = 0.14). Increases in PETCO(2) plateaued at this level, although PAQt continued to increase. When PETCO(2) was more than 30 mm Hg, all PAQt and TDCO values were >4.0 L/min (>2.0 L/min/m(2)). When PETCO(2) exceeded 34 mm Hg, all values of PAQt, and 28/29 values of TDCO were more than 5 L/min (>2.5 L/min/m(2)). One patient had TDCO of 4.69 L/min (2.39 L/min/m(2)). In normothermic patients without significant pulmonary disease, PETCO(2) is a useful index of PAQt during separation from CPB. Under the clinical settings in this study, a PETCO(2) greater than 30 mm Hg was invariably associated with a CO more than 4.0 L/min or a cardiac index >2.0 L/min/m(2).

Aged↗
PubMed2000

A comparison of antagonism of rocuronium-induced neuromuscular blockade during sevoflurane and isoflurane anaesthesia.

Volatile anaesthetic agents potentiate neuromuscular blocking agents and retard their rate of reversal. We hypothesised that there was a difference in the rate of reversal of rocuronium-induced neuromuscular blockade based on the selection of inhalation agent. Thirty-eight patients undergoing elective surgical procedures received either sevoflurane or isoflurane, by random allocation. Neuromuscular blockade was induced using rocuronium 0.6 mg.kg-1 followed by continuous intravenous infusion to maintain 90% suppression of the single twitch response. Upon completion of surgery, the rocuronium infusion was discontinued, neostigmine 50 microg.kg-1 and glycopyrrolate 10 microg.kg-1 were administered. Times from reversal to T1 = 25, 50 and 60% and train-of-four ratio = 0.6 were recorded. The mean (SD) times to train-of-four ratio = 0.6 in the isoflurane and sevoflurane groups were 327 (132) and 351 (127) s, respectively. The mean (SD) times to single twitch response T1 = 25, 50 and 60% in the isoflurane group were 81 (33), 161 (59) and 245 (84) s, respectively, and in the sevoflurane group were 95 (35), 203 (88) and 252 (127) s, respectively. It is concluded that reversal of rocuronium-induced neuromuscular blockade is similar during isoflurane and sevoflurane anaesthesia.

Adult↗
PubMed1997

Minimally invasive direct coronary artery bypass: our experience with 32 patients.

From January 1996 to May 1997, minimally invasive direct coronary artery bypass (MIDCAB) through a small anterior thoracotomy without cardiopulmonary bypass was completed in 31 of 32 patients (Male: Female=1.9:1, mean age=64.6 years, 11 (34.4%)>70 years). Twenty, five, and seven patients had one, two, and three vessel disease respectively. Twelve patients presented with unstable angina, seven had prior myocardial infarction, one had a pre-operative intra-aortic balloon pump, and four had prior coronary artery bypass grafting (CABG). Eight were diabetic, five had chronic obstructive pulmonary disease, and one was morbidly obese. Our newly developed coronary artery immobilizing and occluding device facilitated the coronary anastomosis. There were no post-procedure deaths, no peri-operative myocardial infarctions, and no strokes. One patient required intra-operative conversion to conventional CABG for an intramyocardial target vessel. Two patients had conversion after post-operative angiogram demonstrated incorrect target identification and early graft occlusion. Four patients had limited access graft revision (two kinks, one graft injury, and one haemorrhage). Thirty-one of the 32 patients were followed from 0.5 to 16 months and 30 reported no post-operative cardiac events (one required PTCA to another vessel). We conclude that MIDCAB is safe and effective.

Adult↗
PubMed1997

The acquisition of herpes simplex virus during pregnancy.

BACKGROUND: The acquisition of genital herpes during pregnancy has been associated with spontaneous abortion, prematurity, and congenital and neonatal herpes. The frequency of seroconversion, maternal symptoms of the disease, and the timing of its greatest effect on the outcome of pregnancy have not been systematically studied. METHODS: We studied 7046 pregnant women whom serologic tests showed to be at risk for herpes simplex virus (HSV) infection. Serum samples obtained at the first prenatal visit, at approximately 16 and 24 weeks, and during labor were tested for antibodies to HSV types 1 and 2 (HSV-1 and HSV-2) by the Western blot assay, and the results were correlated with the occurrence of antenatal genital infections. RESULTS: Ninety-four of the women became seropositive for HSV; 34 of the 94 women (36 percent) had symptoms consistent with herpes infection. Women who were initially seronegative for both HSV-1 and HSV-2 had an estimated chance of seroconversion for either virus of 3.7 percent; those who were initially seropositive only for HSV-1 had an estimated chance of HSV-2 seroconversion of 1.7 percent; and those who were initially HSV-2-seropositive had an estimated chance of zero for acquiring HSV-1 infection. Among the 60 of the 94 pregnancies for which the time of acquisition of HSV infection was known, 30 percent of the infections occurred in the first trimester, 30 percent in the second, and 40 percent in the third. HSV seroconversion completed by the time of labor was not associated with an increase in neonatal morbidity or with any cases of congenital herpes infection. However, among the infants born to nine women who acquired genital HSV infection shortly before labor, neonatal HSV infection occurred in four infants, of whom one died. CONCLUSIONS: Two percent or more of susceptible women acquire HSV infection during pregnancy. Acquisition of infection with seroconversion completed before labor does not appear to affect the outcome of pregnancy, but infection acquired near the time of labor is associated with neonatal herpes and perinatal morbidity.

Adult↗
PubMed1996

Pulsed wave Doppler measurement of cardiac output from the right ventricular outflow tract.

Doppler ultrasound can be used to measure cardiac output (CO). Intraoperative Doppler cardiac output (DCO) by transesophageal echocardiography (TEE) has been studied using blood flow velocity from the left ventricular outflow tract (LVOT), the mitral valve (MV), and the main pulmonary artery (MPA). The purpose of this study was to compare DCO, measured from a relatively new TEE view of the right ventricular outflow tract (RVOT), with thermodilution cardiac output (TDCO). We also compared changes in DCO from the RVOT to changes in TDCO. A 5.0/3.7 MHz multiplane TEE probe was placed in 45 adult cardiac surgical patients undergoing general anesthesia. Patients were excluded if there was greater than mild tricuspid valve insufficiency. From the transgastric view, at approximately 110-140 degrees, the RVOT was imaged. DCO was calculated from 1) the time-velocity integral (TVI) using pulse wave (PW) Doppler, 2) the area of the RVOT (measured in early systole using the diameter (pi(D/2)2) of the RVOT at the level of the PW Doppler sample volume), and 3) the heart rate. Simultaneous TDCO was performed by a separate examiner. The RVOT was imaged satisfactorily in 84% of patients (38/45). The mean bias between DCO and TDCO was -0.01 L/min (2 SD +/- 0.45 L/min; n = 38). There was good correlation between DCO and TDCO (R2 = 0.97). Changes in TDCO and changes in DCO were compared in 15 patients. The mean bias between changes in DCO and changes in TDCO was 0.04 L/min (2 SD +/- 0.66 L/min). Analysis of the changes in DCO and TDCO showed good correlation (R2 = 0.96). We conclude that there is a good correlation between DCO measured from the RVOT and TDCO. This technique permits cardiac output measurement without the necessity of placing a pulmonary artery catheter, and it also provides a method of evaluating RVOT blood flow.

Adult↗
PubMedDate not supplied

Transabdominal amnioinfusion in preterm pregnancies complicated by fetal growth restriction, oligohydramnios and umbilical cord compression.

Fetal growth restriction with oligohydramnios occurring in the preterm gestation is associated with significant fetal morbidity and mortality. We investigated the possibility that transabdominal amnioinfusion might relieve acute cord compression and allow prolongation of gestation long enough to administer corticosteroids. Four patients with fetal growth restriction, oligohydramnios and evidence of significant cord compression with otherwise reassuring fetal heart rate testing underwent transabdominal amnioinfusion. Pregnancy was prolonged 22, 38, 10 and 9 days, and cord compression was relieved in all cases. One patient showed findings consistent with reversal of chronic hypoxemia with stabilization of amniotic fluid index measurements in the normal range and normalization of fetal growth. Transabdominal amnioinfusion may be useful as an adjunctive technique to prolong pregnancy in preterm gestations with fetal growth restriction, oligohydramnios and evidence of umbilical cord compression.

Adrenal Cortex Hormones↗