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John C Morrison

Publications and source records attributed to John C Morrison.

At least 55 records · Page 3Linked to original sources
PubMed2004

Infectious necrosis with dehiscence of the uterine repair complicating cesarean delivery: a review.

UNLABELLED: The authors summarize current knowledge about infectious uterine incisional necrosis/dehiscence, an uncommon but serious complication of cesarean delivery. A MEDLINE search of the literature from 1966 to the present did not identify any previous review of this entity. From case reports, small case series, and textbook descriptions, the evidence regarding the definition of the disorder, its prevalence, etiology, pathogenesis, diagnosis, prognosis, and management is presented. The paucity of reports in the modern literature indicate the need for further studies to more precisely characterize this entity for cross-study comparisons and aggregation to provide clearer management guidelines, especially as it regards diagnosis, and the safety of conservative surgery in well-selected cases. TARGET AUDIENCE: Obstetricians & Gynecologists, Family Physicians. LEARNING OBJECTIVES: After completion of this article, the reader should be able to define the condition infectious uterine incisional necrosis, and to outline potential management options.

Cesarean Section↗
PubMed2004

Does the frequency of outpatient visits in addition to the regularly scheduled prenatal visits identify a poor pregnancy outcome?

Do extra outpatient visits, in addition to regularly scheduled visits, identify a pregnancy at risk of an adverse outcome? This prospective investigation analysed additional outpatient visits, by low-risk obstetric patients. One hundred and sixty-two women were evaluated with one to two additional visits and 66 had three or more visits. Antepartum and intrapartum pregnancy complications between groups was similar suggesting that frequency of additional visits does not identify a pregnancy at risk for an adverse outcome.

Adolescent↗
PubMed2004

Microarray analysis of changes in mRNA levels in the rat retina after experimental elevation of intraocular pressure.

PURPOSE: The goal of this study was to identify altered patterns of retinal mRNA expression after experimental elevation of intraocular pressure (IOP) in a rat glaucoma model. METHODS: Brown Norway rats (N = 16) received unilateral episcleral vein injection of hypertonic saline to elevate IOP. IOP was monitored daily by handheld tonometer, and retinas were collected 8 days and 5 weeks after surgery. Comparison of mRNA levels between experimental and fellow retinas was made using gene microarrays (rat U34A rat arrays; Affymetrix, Santa Clara, CA). Semiquantitative RT-PCR was used to confirm selected results from array analysis and to compare with alterations after optic nerve transection. RESULTS: IOP elevation for 5 weeks resulted in reproducible changes in levels of 81 mRNAs. Of these, 74 increased, whereas only 7 decreased. The expression levels of 27 of these same messages were changed after 8 days of IOP elevation. In addition, four other genes demonstrated altered expression after the shorter period of elevated IOP exposure. Approximately half of the mRNAs with altered expression were associated with either neuroinflammatory responses or apoptosis. For 25 of the selected functionally relevant messages altered by array analysis, the alterations were confirmed by semiquantitative RT-PCR. The levels of 24 of 25 selected messages were also changed after optic nerve transection. CONCLUSIONS: The activation of glia and the complement system after IOP elevation, which is similar to that described in several neurodegenerative diseases and after optic nerve transection, suggests that this rat glaucoma model could be used to evaluate the neuroprotective potential of therapeutic agents that target these processes.

Animals↗
PubMed2004

Selective ganglion cell functional loss in rats with experimental glaucoma.

PURPOSE: To characterize retinal functional consequences of elevated intraocular pressure (IOP) in a rat model of experimental glaucoma. METHODS: Unilateral elevation of IOP was produced by hypertonic saline injection into an episcleral vein in 20 adult male Brown-Norway rats. IOP was measured in both eyes of awake animals four to five times per week. After 5 weeks, animals were dark adapted overnight (>12 hours) and full-field electroretinograms (ERGs) were obtained simultaneously from both eyes. Scotopic ERG stimuli were brief white flashes (-6.64-2.72 log cd-s/m(2)). Photopic responses were also obtained (0.97-2.72 log cd-s/m(2)) after 15 minutes of light adaptation (150 cd/m(2)). Eyes were processed the following day for histologic evaluation by light microscopy, including masked determination of optic nerve injury grade (ONIG; 1, normal; 5, severe, diffuse damage). RESULTS: Among experimental eyes, the group average IOP (+/-SD) was 34.5 +/- 4.1 mm Hg, whereas the average for control eyes was 28.1 +/- 0.5 mm Hg (t = 7.1, P < 0.0001). The average ONIG for experimental and control eye groups, respectively, was 3.4 +/- 1.7 and 1.0 +/- 0.02 (t = 6.3, P < 0.0001). The ONIG increased with mean IOP in experimental eyes (r(2) = 0.78, P < 0.0001) and was unrelated to mean IOP in control eyes (r(2) = 0.09, P = 0.18). In experimental eyes with relatively mild IOP elevation (mean IOP < 31 mm Hg) and no structural (histologic) damage to the optic nerve evident by light microscopy (ONIG = 1.1 +/- 0.2, n = 5), there was a selective reduction of the positive scotopic threshold response (pSTR; P < 0.001), whereas other ERG components remained unaltered. In four of the five eyes, pSTR amplitude was reduced by more than 50%, whereas all five had normal scotopic a-wave, b-wave, and OP amplitudes. Eyes with mean IOP of more than 35 mm Hg had reduced a-wave, b-wave, and oscillatory potential (OP) amplitudes. CONCLUSIONS: As demonstrated by prior studies, selective loss of the pSTR is indicative of selective retinal ganglion cell (RGC) injury. In this rat model of experimental glaucoma, selective RGC functional injury occurred before the onset of structural damage, as assessed by light microscopy of optic nerve tissue. The highest IOP levels resulted in nonselective functional loss. Thus, in rodent models of experimental glaucoma, lower levels of chronically elevated IOP may be more relevant to human primary chronic glaucoma.

Animals↗
PubMed2004

Diagnosis of postpartum infections: clinical criteria are better than laboratory parameter.

BACKGROUND: Physiologic increases in the leukocyte count and segmental neutrophil percentage during pregnancy alter the ability of these indices to predict infection. METHODS: Women with cesarean deliveries were assessed by leukocyte counts and segmented neutrophil percentage as well as clinical signs to detect postoperative infection. RESULTS: In 157 consecutive patients undergoing cesarean deliveries there was a significant physiologic increase between the preoperative and postoperative leukocyte count (12.4 +/- 3.9/uL vs. 14.8 +/- 3.4/uL, P < 0.001). The leukocyte count after delivery did not discriminate whether or not the patient would develop a postpartum infection or have significant hyperpyrexia. CONCLUSION: Due to physiologic changes associated with pregnancy, the leukocyte count and segmented neutrophil percentage do not predict infection. Therefore clinical findings are most important in diagnosing postpartum infections.

Adult↗
PubMed2004

Acute colonic pseudo-obstruction following cesarean delivery.

Acute colonic pseudo-obstruction remains an uncommon complication in obstetric practice, but when it occurs, it is most frequently noted after cesarean delivery. Acute colonic pseudo-obstruction is characterized by the findings consistent with large bowel obstruction in the absence of a demonstrable mechanical cause as noted in this case report. We report the occurrence of acute colonic pseudo-obstruction post-cesarean delivery in which prompt recognition of impending cecal perforation allowed appropriate management by tube cecostomy. Although acute colonic pseudo-obstruction is uncommon, it is important that obstetric practitioners recognize this clinical entity as the potentially fatal consequences of cecal perforation can be prevented by tube cecostomy.

Acute Disease↗
PubMed2003

Positron emission tomography scanning in essential blepharospasm.

PURPOSE: To localize in the brain using positron emission tomography neuroimaging with (18)fluorodeoxyglucose [PET ((18)FDG)] differences in glucose metabolism between patients with essential blepharospasm (EB) and controls. DESIGN: Prospective case-control study. METHODS: Positron emission tomography neuroimaging with (18)fluorodeoxyglucose was performed in 11 patients with EB and 11 controls matched for age and gender. Global analysis of images was used to localize differences in glucose metabolism between groups. RESULTS: Multiple cortical and subcortical abnormalities were observed in EB patients in comparison with controls. Cortical areas with the largest and most significant clusters of increased glucose uptake were the inferior frontal gyri, right posterior cingulate gyrus, left middle occipital gyrus, fusiform gyrus of the right temporal lobe, and left anterior cingulate gyrus. Cortical areas with the largest and most significant clusters of decreased glucose uptake were the inferior frontal gyri, ventral to the area of increased glucose metabolism. Subcortical abnormalities, consisting of increased glucose uptake, involved the right caudate and consisting of decreased glucose uptake, involved the left inferior cerebellar hemisphere and thalamus. CONCLUSIONS: Global analysis of positron emission tomography neuroimaging with (18)fluorodeoxyglucose neuroimaging in EB patients in comparison with controls demonstrates a pattern of abnormalities involving several cortical and subcortical areas that control blinking, including the inferior frontal lobe, caudate, thalamus, and cerebellum.

Adult↗
PubMed2003

Current status of home uterine activity monitoring.

A comprehensive evidence-based review of the clinical data leads to the conclusion that if patients at high risk for preterm birth (eg, prior preterm birth because of preterm labor, twins and higher-order multiple gestation, women who have preterm labor during the current pregnancy tocolyzed effectively) use the comprehensive system of HUAM correctly (ie, daily nursing care and twice-daily monitoring) with appropriate alarm rates and sensitive monitors, the incidence of early diagnosis of preterm labor, effective prolongation of pregnancy with fewer preterm births, and a reduction in neonatal morbidity is always demonstrated when the study group is compared with a control group consisting of women receiving standard care available to obstetricians in the United States. The authors expect that there will always be arguments regarding whether the monitor or the nurse contributes most to preterm birth reduction. Even when the alerts of detected contractions or patient-reported symptoms are sounded, the issue of prompt and effective medical intervention will always be hotly debated. The appropriate research design that tests HUAM while allowing various diagnostic and treatment modalities that physicians employ around the United States must be individualized. Physicians must make the decision, based on the evidence, regarding whether or not this system would benefit their patients. While investigators argue about research designs and statistical analyses, physicians simply want the best outcomes for their patients, which is what women and the whole of society also want. Based on the available evidence, it is clear that when the comprehensive system of HUAM is used appropriately in the right patients, everyone benefits.

Cardiotocography↗
PubMed2003

Evaluation of a rat model of preeclampsia for HELLP syndrome characteristics.

OBJECTIVE: To determine whether a rat model of preeclampsia includes features consistent with HELLP (hemolysis, elevated liver enzymes, low platelets) syndrome. METHODS: Preeclampsia was induced experimentally in timed-pregnant Sprague-Dawley rats using the reduced uterine perfusion pressure (RUPP) model. On day 14 of gestation, silver clips were placed around the aorta below the renal arteries and on the left and right uterine arcade at the ovarian artery. All animals were chronically instrumented to determine conscious blood pressure and to obtain blood samples for analysis of complete blood count, platelet count, liver function tests, uric acid, creatinine, and albumin. Blood samples were collected and animals sacrificed on day 19 of gestation, at which time placental and pup weight were obtained. A control group was analyzed similarly. Statistical analysis was performed with the Student t test. RESULTS: The RUPP model animals (n = 8), when compared with the normotensive controls (n = 9), did not show a statistically significant difference in hemoglobin, platelets, liver function tests, uric acid, creatinine, or albumin, although the mean arterial pressure was higher (mean +/- SD 131.9 +/- 17.1 mmHg versus 104.0 +/- 14.0 mmHg, respectively; P = .003) and pup number was lower (RUPP 6.6 +/- 2.4 versus control 13.8 +/- 2.3, P < .001). CONCLUSION: Although decreased uteroplacental perfusion induces changes similar to symptoms of preeclampsia, the RUPP rat model does not appear to express features of HELLP syndrome.

Animals↗
PubMed2003

Predictability of intrapartum and neonatal outcomes with the amniotic fluid volume distribution: a reassessment using the amniotic fluid index, single deepest pocket, and a dye-determined amniotic fluid volume.

OBJECTIVE: The purpose of this study was to establish whether ultrasound-estimated or dye-determined amniotic fluid distribution (upper compared with lower quadrant) is predictive of perinatal outcome. STUDY DESIGN: Amniotic fluid distribution as measured by the amniotic fluid index, single deepest pocket, and dye-determined volumes was ascertained and correlated with intrapartum and neonatal outcomes. RESULTS: Between January 1997 and January 2001, 135 women (70 upper-greater and 65 lower-greater) participated in this prospective observational study. The sum of the amniotic fluid index (P =.309), single deepest pocket (P =.168), and dye-determined amniotic fluid volume (P =.368) for the upper-greater compared with the lower-greater groups were similar. Decelerations in labor (P =.597), late decelerations (P =.999), cesarean deliveries for fetal distress (P =.413), and umbilical cord pH < 7.2 were similar (P =.647) CONCLUSION: Ultrasound-estimated and dye-determined amniotic fluid volumes are similar between upper-greater and lower-greater groups, and intrapartum/neonatal outcomes are not affected by the amniotic fluid distribution.

Adult↗
PubMed2003

Continuous subcutaneous terbutaline administration prolongs pregnancy after recurrent preterm labor.

OBJECTIVE: This study was undertaken to study the effectiveness of continuous subcutaneous terbutaline (SQT) in the home after recurrent preterm labor (RPTL). STUDY DESIGN: Women with RPTL at less than 32 weeks' gestation were treated with continuous SQT administered in the home compared with matched control patients. RESULTS: Fifteen SQT patients were compared with 45 women (3:1) treated with no tocolytic therapy after hospitalization. Gestational age at delivery more than 37 weeks (53% vs 4%), percentage delivered at less than 32 weeks (0% vs 47%), overall and pregnancy prolongation (49.8 +/- 19.2 days vs 24.5 +/- 12.8 days) were all significantly better in the study group (P <.001). The total number of maternal hospital days (9.8 +/- 2.1 vs 15.9 +/- 7.4, P <.0001), duration of NICU stay (1.9 +/- 4.9 vs 19.8 +/- 29.3 days, P <.001), and total cost for newborn care (6,995 +/- 14,822 US dollars vs 62,033 +/- 89,978 US dollars, P <.002) favored the study patients. For every dollar spent on SQT, there was a savings of 4.67 US dollars in newborn hospital costs for control patients. CONCLUSION: In this small study, the use of SQT significantly prolongs pregnancy, decreases serious neonatal complications, and reduces the duration of hospitalization for both mother and infant, as well as neonatal costs.

Adult↗
PubMed2003

Vaginal birth after cesarean section versus elective repeat cesarean delivery: Weight-based outcomes.

OBJECTIVE: The study was undertaken to compare infectious morbidity and trial of labor (TOL) success stratified by weight in women. STUDY DESIGN: Vaginal birth after cesarean section (VBAC) candidates were divided into groups based on prepregnancy weight: group I, 70 (<200 pounds); group II, 70 (200-300 pounds); and group III, 69 (>300 pounds). RESULTS: The TOL success rate was 81.8% in group I compared with 57.1% in group II and 13.3% in group III (P =.001). The overall infectious morbidity was significantly greater in the obese women 39% (P =.001) compared with the average women at 11.4% and the lean women at 5.7%. CONCLUSION: Infectious morbidity is increased and VBAC success is reduced in patients who weigh more than 300 pounds.

Adult↗
PubMed2003

Maternal and perinatal complications with uterine rupture in 142,075 patients who attempted vaginal birth after cesarean delivery: A review of the literature.

OBJECTIVE: The purpose of this study was to determine the rate of uterine rupture and its complications as the result of trial of labor after previous cesarean delivery. STUDY DESIGN: PubMed was searched from 1989 to 2001, with the terms "VBAC, uterine rupture," "trial of labor, uterine rupture," "cesarean delivery, uterine rupture," and "scarred uterus, rupture." For inclusion, reports had to contain data from at least 100 patients with trials of labor that included a description of adverse outcomes. Duplicate reporting from a single institution was excluded. Odds ratios and 95% CIs were calculated. RESULTS: Seventy-two of the 361 articles (20%) that were identified met the inclusion criteria. A 6.2 per 1000 trial of labor rate of uterine rupture (total=880 uterine ruptures in 142,075 trials of labor) was determined. For every 1000 trials of labor the uterine rupture-related complication rate was 1.8 for packed red blood cell transfusion, 1.5 for pathologic fetal acidosis (cord pH<7.00), 0.9 for hysterectomy, 0.8 for genitourinary injury, 0.4 for perinatal death, and 0.02 for maternal death. The perinatal mortality rate was significantly lower among studies from the United States versus other countries (0.3 vs 0.6; odds ratio, 0.50; 95% CI, 0.26-0.94) and in series that exceeded 1000 patients (0.2 vs 1.7; odds ratio, 7.34; 95% CI, 3.94-13.69). CONCLUSION: Although relatively uncommon, uterine rupture is associated with several adverse outcomes, depending on the time of the publication and the site and size of the population that was studied.

Female↗
PubMed2003

Clinical and sonographic estimations of uterine weight.

Over a 36 month period, all hysterectomies with clinical assessment, sonographic measurement of uterine length and estimated uterine weight were reviewed. Accuracy of these methods was ascertained by: 1) mean error, 2) mean standardized error, and 3) percentage of estimates within 10% of the actual weight. Among 210 hysterectomies, the mean (+/- standard deviation) of uterine weight was 514.9 gm +/- 647.0 gm (range 54-6700 gm) with 135 specimens (64.3%) being 500 gm and 75 > 500 gm. The receiver-operating curves for clinical assessment (0.82 +/- 0.03), uterine length (0.87 +/- 0.03) and Linear Regression Equation (0.82 +/- 0.04) are not significantly different (P > 0.05), having similar abilities to differentiate uterine weight. The clinical estimate of uterine weight is as accurate as ultrasound in determining a uterus weighing > 500 gm but all three methods poorly predict actual uterine weight.

Adult↗
PubMed2003

Uterine incisional necrosis complicating cesarean section.

OBJECTIVE: To establish the clinical features of patients with necrosis of the uterine incision after cesarean delivery because of the paucity of modern reports in the literature. STUDY DESIGN: Over a 4-year period, the records of 6 patients with this complication were reviewed. RESULTS: Three patients presented within 48-72 hours of delivery with clinical features very similar to those of bowel perforation. One patient had fascial dehiscence on day 5 after delivery. Two cases presented 2 and 6 weeks after delivery with postpartum hemorrhage without peritoneal findings. Diagnosis was not made prior to surgery in any case. All patients recovered after hysterectomy. CONCLUSION: While the major risks with this uncommon but important complication are serious infectious morbidity and mortality, in our patients these risks were avoided but at the cost of hysterectomy in a group of young women of low parity. More data in the future might establish a basis for rational management, possibly including conservative surgery in selected cases.

Adolescent↗
PubMed2002

Cervical ripening and induction of labor with misoprostol, dinoprostone gel, and a Foley catheter: a randomized trial of 3 techniques.

OBJECTIVE: The purpose of this study was to compare the efficacy of 3 different techniques of cervical ripening and induction. STUDY DESIGN: Patients who required cervical ripening and induction were randomized to one of 3 groups: (1) supracervical Foley catheter and intravaginal dinoprostone gel, (2) supracervical Foley catheter and 100 microg oral doses of misoprostol, or (3) serial 100-microg oral doses of misoprostol. Intravenous oxytocin was administered when a protraction disorder of labor was identified. RESULTS: There were 339 women randomized. There was no significant difference in the time from first intervention to delivery in the 3 groups (P =.546). In each group, a similar percentage of women required oxytocin (P =.103). The rates of cesarean delivery were equivalent among the groups (P =.722). Rates of tachysystole were high but statistically equivalent among the 3 groups. There were no significant differences in Apgar scores or umbilical artery pH. CONCLUSION: Oral 100 microg serial doses of misoprostol, with or without the use of a supracervical Foley catheter, were equivalent to the use of a supracervical Foley catheter and serial 4-mg doses of dinoprostone gel for cervical ripening and the induction of labor.

Adult↗
PubMed2002

Subcutaneous stitch closure versus subcutaneous drain to prevent wound disruption after cesarean delivery: a randomized clinical trial.

OBJECTIVE: The purpose of this study was to compare a subcutaneous stitch closure and subcutaneous drain placement for the risk of wound disruption after cesarean delivery. STUDY DESIGN: This was a prospective randomized clinical trial that evaluated subcutaneous stitch closure, placement of a subcutaneous drain, or no closure for subsequent wound disruption risk in women with subcutaneous depth at >or=2 cm. RESULTS: The maternal demographics and intrapartum risk factors for postoperative wound disruptions were similar among the 964 study subjects, who were divided into 3 groups. Wound disruptions that required opening of the wound, irrigation, debridement, packing, and/or secondary delayed closure occurred in 9.7% of the women with no closure, 10.4% of the women in the stitch closure group, and 10.3% of the women in the closed drain group (P =.834). CONCLUSION: There appears to be no difference in the subsequent risk of wound complications when no closure of the subcutaneous tissue layers occurs versus suture closure or a closed drainage system.

Adult↗