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M Nusbaum

Publications and source records attributed to M Nusbaum.

At least 19 recordsLinked to original sources
PubMed1998

Predicting surgical outcome using Bayesian analysis.

Surgical outcome analysis is best performed using Bayesian statistics. The ability of this type of analysis to take into consideration multiple parameters affecting surgical outcome is a marked improvement over single-condition probabilities that ignore the many degrees of freedom in the dynamics of a surgical intervention. To illustrate the power of a Bayesian analysis a surgical population of 1017 patients undergoing cholecystectomy, colon resection, and appendectomy was developed. Each patient was assigned to a mutually exclusive outcome group (D1, survival; D2, survival with complications; D3, nonsurvival). A priori outcome probabilities for the population were D1 = 0.917, D2 = 0.066, and D3 = 0.017. A conditional probability matrix (CPM) was then developed for 59 patient parameters (Sj) that may have affected outcome. The CPM contained the conditional probability that a parameter was present given the known outcome P(Sj/Di). Once the CPM was matured Bayesian analysis allowed one to predict the surgical outcome given any set or combination of patient parameters P(Di/Sj). Posterior probabilities generated by the Bayes analysis allowed one to investigate the effect of a single parameter or any group of parameters on outcome. Criterion based validity testing based on comparison of Bayesian outcomes versus the surgeons perception of outcomes for computer simulated surgery on 15 artificial patients suggests that this type of analysis provides insightful and educational data to the operating surgeons (V-mortality = 0.547, SEE = 24.46; V-morbidity = 0.319, SEE = 25.86). Objective outcome analysis or surgical peer review cannot be fairly accomplished unless the statistical methodology takes into consideration all of the parameters affecting outcome. This study concludes that Bayes Theorem provides the ideal statistical framework for performing an outcome analysis that considers the many parameters affecting the results of a surgical intervention.

Adolescent↗
PubMed1998

Manometric measurement of anal canal resting tone: comparison of a rectosphincteric balloon probe with a water-perfused catheter assembly.

The purpose of this study was to compare the manometric measurements of a rectosphincteric balloon probe with a water-perfused catheter assembly on anal canal resting tone. Ten normal subjects (9 males, 1 female; mean age: 32 years; range 27-46 years) underwent station pull-through (0.5 cm/3 sec) beginning in the rectum with a water-perfused catheter assembly and a rectosphincteric balloon probe. Both the probe and the catheter were 5 mm in diameter. Three catheter side ports were perfused at 1 ml/min, and the rectal balloon was inflated with 5 ml of air. Measurements were taken on the same day in a counterbalanced manner. Data were analyzed on a computerized system. Mean (+/-SEM) values with the balloon were 82.3 (+/-8.9) mm Hg and 97.1 (+/-9.3) mm Hg with the catheter. These values were not significantly different (P=0.22). A significant order effect (P=0.04) was found where the first measure (101.3+/-10.2 mm Hg) was higher than the second measure (78.1+/-6.6 mm Hg), which was controlled for in the experimental design. A rectosphincteric balloon probe can accurately measure the resting tone of the anal canal compared to a water-perfused catheter assembly. Caution should be used when measuring anal canal resting tone early in an anorectal manometry assessment.

Adult↗
PubMed1991

[Sustained release verapamil in essential hypertension].

The efficacy of sustained release verapamil (Ikapress) was investigated in 237 hypertensive patients of both sexes in a multicenter trial in family practice. There were 4 groups: patients without previous treatment and those treated with nifedipine, with atenolol, or with a combination of drugs. After 4-7 days of washout, all those with diastolic pressures of 95 mm Hg or above received once daily 240 mg of verapamil for 8 weeks. 27 cases had to be withdrawn because of adverse effects: weakness in 10, constipation in 6, rash in 4, impotence in 3, and in 4, other reasons. In 177 blood pressure was brought under control after 4 weeks of treatment. An additional 33 were controlled after 4 weeks of 360 mg of sustained release verapamil. Response to treatment was similar in the 4 trial groups. Mean systolic and diastolic pressures fell 19 and 16 mm Hg, respectively, and mean pulse rate decreased by 5 beats/min. Constipation was the only side-effect reported by those who completed the trial. However, there was a significant reduction in initial scores for headache, dizziness, numbness and edema after 8 weeks of verapamil and all indices of quality of life were significantly improved. These included scores for general well-being, physical fitness, social activity, job fitness, sexual activity, sleep, concentration and mood. Scores for daytime sleepiness and fatigue also decreased significantly. Thus, sustained-release verapamil in a daily dose of 240-360 mg was shown to be an effective antihypertensive. It had few adverse effects and gave considerable improvement in quality of life.

Blood Pressure↗
PubMed1989

Mucinous cystadenoma: pitfalls of differential diagnosis.

Cystic neoplasms of the pancreas often are difficult to differentiate from pseudocysts. It has been proposed that a history of clinical pancreatitis, elevated serum pancreatic enzymes, elevated cyst fluid amylase, and a communication with the pancreatic duct suggest the diagnosis of a pseudocyst. We report the case of a young woman who presented with a cystic mass in the pancreas and was thought to have a pseudocyst because of the above; at surgery, a mucinous cystadenoma was documented. The pitfalls of differentiating neoplastic cysts of the pancreas from pseudocysts are discussed.

Amylases↗
PubMed1989

Hepatoportal arteriovenous fistula treated with detachable balloon embolotherapy.

Hepatic artery to portal vain fistulas were first reported in 1892. Symptoms of portal hypertension usually occur within weeks to months, once the fistula develops. Various attempts at surgical occlusion and embolization, with varying results, have been reported. This report is of a 33-yr-old woman who, 23 yrs after an automobile accident, was admitted with ascites and diagnosed as having a right hepatic artery-to-portal vein fistula (RHAPVF), which was successfully occluded via detachable balloon embolic therapy. The ascites resolved within 3 days of the embolotherapy, and subsequent follow-up revealed no recurrence of ascites during the next 18 months.

Adult↗
PubMed1988

The energy costs of surgery as measured by the doubly labeled water (2H218O) method.

Energy expenditure before and after surgery was determined in seven patients by the doubly labeled water (2H218O) method (DLW). The values were compared with values obtained by respiratory gas exchange by means of a metabolic measuring cart (MMC). Patients were maintained on total parenteral nutrition before and after trauma. The principal finding was an increase in the rate of CO2 production of 11.9 +/- 5.0% after surgery. This corresponds to a 267 +/- increase in energy expenditure (p less than 0.05). No trauma-associated change in energy expenditure was found with the MMC. The correlation of preoperative values from MMC and DLW was not statistically significant (r = 0.25), nor was the correlation of MMC and the Harris-Benedict equation, but the correlation of DLW with Harris-Benedict equation was statistically significant (r = 0.73, p less than 0.05). We suggest that the discrepancy is because the DLW method measures the cumulative energy expenditure over a period, whereas the MMC gives a "spot" measurement.

Adolescent↗
PubMed1983

Whole-body protein turnover in metabolically stressed patients and patients with cancer as measured with [15N] glycine.

The whole-body protein synthesis rate (PSR) was measured in 5 control patients (group I) and 38 patients in various clinical states (group II). A single pulse of [15N]glycine was given and the PSR calculated from the 15N enrichment in the urinary ammonia excreted over the next 10 hr. The patients' results fell into three separate groups: group IIa patients were nonstressed and had uneventful recoveries (3.1 +/- 0.6 g prot./kg/day), their PSRs were the same as the control group I, (3.1 +/- 1.0 g prot./kg/day); group IIb patients were stressed, had higher PSRs (6.3 +/- 0.9 g prot./kg/day), one of whom died, and the rest had more complications than group IIa; group IIc patients had very high PSRs (15.4 +/- 6.1 g prot./kg/day), all of whom were seriously ill, and 8 out 12 died; Data are +/- 1 SD. The PSR correlated with the serum glutamate oxaloacetate transferase (SGOT, P less than 0.01). We concluded: (i) [15N]glycine cannot be used to measure the PSR in patients with evidence of liver disease; the results are best interpreted in terms of glycine metabolism; (ii) the "apparent" PSR correlated with clinical status; and (iii) an elevated PSR in a patient with a malignancy is not necessarily due to protein metabolism by the tumor.

Adolescent↗
PubMed1981

Ovulatory dysfunction in patients with endometriosis.

The incidence of ovulatory dysfunction (anovulation, oligo-ovulation, and luteal phase defect) in 103 patients with endometriosis and infertility was found to be 27.2%. Ovulatory dysfunction was found to occur at a slightly higher age group than the patients with normal ovulatory pattern (p less than 0.02). Prior use of oral steroidal contraceptives does not increase the incidence of ovulatory dysfunction. In addition, there is no correlation between the duration of infertility, and te incidence of ovulatory dysfunction in this group of patients with endometriosis. This report suggests an association between endometriosis and ovulatory dysfunction in some patients, which adds to the etiology of their infertility. It is also suggested that the diagnosis of endometriosis should be suspected in cases of unexplained infertility, even if the pelvic examination does not have any positive objective findings.

Adolescent↗
PubMed1974

Nonocclusive mesenteric vascular insufficiency.

A case of nonocclusive mesenteric vascular insufficiency in a patient with congestive heart failure on digitalis and with arrhythmia is presented. The preoperative diagnosis was made through mesenteric arteriography. A course of treatment was followed which we believe prevented intestinal gangrene. This regimen includes measures to increase cardiac output, local pharmacologic agents to induce mesenteric vasodilatation, antibiotics, and oxygen. The viability of the intra-abdominal organs was demonstrated by laparotomy.

Angiography↗