Is there a correlation between time of delivery and newborn cord pH?

Purpose: Since more senior and attending physicians work in labor wards during morning shifts, we expect a better delivery outcome during that time period.

Materials and methods: A retrospective study was conducted between 1/2005 and 12/2014. Records of 56 428 singleton deliveries from a tertiary hospital in which cord blood pH was routinely measured at birth were analyzed. Time of birth was divided into shifts: 7 AM–3?PM (morning shift), 3?PM–11?PM (afternoon shift), and 11?PM–7 AM (night shift). Additional stratification compared weekdays and weekend deliveries.

Results: 19?601, 18?429, and 18?398 neonates were born during morning, afternoon, and night shifts, respectively. There was no significant difference in maternal age, neonatal weight, or mean 5-min Apgar score among the three shift periods. Furthermore, there was no correlation between shift time of delivery and newborn acidosis with respect to cord pH less than 7 (0.1% in each time periods, p?=?0.67). Despite the above, instrumental deliveries and cesarean sections were more common in the morning shift compared to the afternoon and night shift, respectively (p?=?0.001 each).

Conclusions: Although shift time of delivery was found to be related to mode of delivery it was not related to either 5-min Apgar score or newborn acidosis as reflected by cord pH.     

Adherence to Daily Oral TDF/FTC for PrEP in Community Health Center Populations: The Sustainable Health Center Implementation PrEP Pilot (SHIPP) Study

AIDS and Behavior - The prevention effectiveness of oral preexposure prophylaxis (PrEP) is highly dependent on medication adherence but no validated longer term PrEP adherence measures are readily...     

Left lower lobe ventilation is reduced in patients with cardiomegaly in the supine but not the prone position

To determine the effect of the heart on regional ventilation, Krypton-81m (81mKr) tomographic (SPECT) ventilation scans were recorded in seven patients with cardiomegaly and four normal subjects in the supine and prone positions. All patients had a cardiothoracic ratio of greater than 0.50 and clear lung fields radiographically. Using standard gamma camera tomographic reconstruction techniques, images of transaxial slices were obtained during a 360 degree rotation around the thorax of the subject breathing the radioactive gas 81mKr. The transaxial images, acquired over 10 min were aligned in each posture at the level of the cardiac apex, mid-heart, and aortic arch and were matched in relation to a radioactive marker on the chest wall and to anatomic landmarks. A horizontal line (gravity independent and parallel to the couch) was drawn on the transaxial section through the dorsal regions of the right and left lung. Counts per resolution element (12 to 15 mm) were plotted along this line and the ratios of the peak values in right and left lung compared. These ratios represent differences in regional ventilation per unit lung volume. In controls the mean left-to-right (L/R) peak count ratio varied from 0.91 to 1.00 at the three levels (range: 0.76 to 1.04); there were no significant differences between supine and prone. In patients with cardiomegaly the mean (+/- SEM) L/R peak count ratio at cardiac apex, mid-heart, and aortic arch was 0.46 (+/- 0.08), 0.55 (+/- 0.07), and 0.89 (+/- 0.08) when supine and 1.04 (+/- 0.07), 1.05 (+/- 0.05), and 1.08 (+/- 0.07) when prone, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)     

ACTH and corticosterone secretion in rats following removal of the neurointermediate lobe of the pituitary gland

Surgical removal of the neurointermediate lobe of the pituitary gland (NIL-X) in the rat resulted in two abnormalities in ACTH secretion: (1) plasma ACTH and corticosterone levels were elevated in the morning and over a 24-hour period compared with levels in control (NIL-C) rats, and (2) although NIL-X and NIL-C rats had acute increases in plasma ACTH and corticosterone of equal magnitude after interoceptive stimuli (hemorrhage, surgery), NIL-X rats demonstrated markedly smaller elevations in plasma levels of these hormones after neurotropic stimuli (noise, novel environment). This subnormal adrenocortical response of NIL-X rats was not due to an impairment in perception of a neurotropic stimulus; these rats had normal latencies to paw licking and to jumping off a heated surface, yet smaller increases in plasma corticosterone after the stimulus. The impairment in ACTH response was not related to stimulus intensity, as NIL-X and NIL-C rats had equal ACTH and corticosterone secretion during both low and high levels of insulin-induced hypoglycemia. NIL-X rats demonstrated a significant elevation in daily water intake, although hematocrit, plasma Na+, K+, osmolality and protein were normal. Significant diurnal rhythms in plasma corticosterone levels and in water intake were maintained as well. The elevated morning plasma ACTH levels, the blunted hormone increases after noise, and the increase in water intake persisted in NIL-X rats 2 months after surgery. These data indicate that removal of the NIL results in (1) chronic elevations in basal ACTH and corticosterone secretion, and (2) chronic impairment in adrenocortical responses to neurotropic stimuli, but not to interoceptive stimuli. The deficit is not due to impaired perceptual capacity nor to the intensity of the stimulus.     

Spectrum of coronary arterial spasm. Clinical, angiographic and myocardial metabolic experience in 29 cases

A relationship of coronary arterial spasm to variant angina pectoris, subendocardial ischemia, major ventricular arrhythmias and myocardial infarction has been demonstrated. In 29 patients, spasm was angiographically observed in normal-appearing coronary arteries (7 patients) as well as superimposed on various degrees of coronary atherosclerotic obstruction (22 patients). All patients experienced an atypical anginal syndrome; 16 patients also experienced typical exertional angina. Coronary spasm appeared to be a major contributory factor in eight occurrences of myocardial infarction and in 11 incidents of ventricular tachycardia, ventricular fibrillation and heart block.

Coronary spasm in the 29 cases was distributed in the following fashion: left main trunk, 6 cases; right main trunk, 12 cases; proximal left anterior descending artery, 13 cases; proximal circumflex artery, 1 case; distal left anterior descending artery, 1 case; and distal circumflex artery, 2 cases. In 5 cases coronary spasm was noted at multiple sites.

In contrast to findings in patients manifesting only typical exertional angina, the hemodynamic findings during spasm were those of a hypodynamic state. Left ventricular systolic pressure decreased from 138.9 ± 6.0 (mean ± standard error of the mean) to 113.2 ± 6.2 mm Hg; left ventricular end-diastolic pressure did not change significantly. Myocardial lactate extraction during spasm was invariably markedly reduced: −53.19 percent ± 15.44 (P < 0.001). However, the effect of coronary sinus pacing on myocardial lactate extraction was not significantly abnormal: +15.74 percent ± 6.66.

The respective roles of medical and surgical intervention are uncertain. Only 3 patients had a completely satisfactory pharmacologic response to nitrates alone or in combination with propranolol, and the condition of 5 others was partially improved; the remaining 21 patients were judged intractable to medical management. Coronary bypass surgery was performed as the ultimate recourse in 18 patients. However, short-term results reveal that only nine (50 percent) showed improvement, four (22 percent) had myocardial infarction during or after surgery and four (22 percent) died.

These studies confirm that coronary arterial spasm is a definite pathogenetic factor in a variety of acute myocardial ischemic syndromes. The incidence and full clinical significance of this functional disorder remain to be determined.     

Effect of the sympathetic nervous system on limb circulation and metabolism during exercise in patients with heart failure

During exercise in patients with heart failure, activation of sympathetic vasoconstrictor nerves may impair vasodilation in active skeletal muscle and thereby interfere with skeletal muscle blood flow. To investigate this hypothesis, we examined the effect of acute alpha-adrenergic blockade with systemic administration of prazosin (10 patients) or regional administration of phentolamine (eight patients) on blood flow, vascular resistance, oxygen consumption (VO2), and lactate release in the leg during maximal bicycle exercise in patients with heart failure. During control exercise, systemic VO2 increased to 12.6 +/- 4.3 ml/min/kg (normal greater than 20 to 25 ml/min/kg), leg blood flow to 2.8 +/- 1.8 liters/min, and leg lactate release to 362 +/- 256 mg/min. Prazosin decreased systemic vascular resistance (12.5 +/- 3.2 to 9.7 +/- 2.5 units; p less than .003) and mean arterial pressure (101 +/- 20 to 87 +/- 22 mm Hg; p less than .002) at maximal exercise, supporting the presence of substantial sympathetic vasoconstrictor nerve activity. Prazosin also decreased leg resistance during exercise. However, the magnitude of leg blood flow, leg oxygen extraction, and leg VO2 during exercise were unchanged, suggesting that vasodilation in the leg was produced by an autoregulatory response to the drop in blood pressure rather than by blockade of sympathetic vasoconstriction. Maximal systemic VO2 and leg lactate release were also not improved. Regional blockade with phentolamine did not substantially drop the arterial blood pressure and had no effect on vasodilation, blood flow, VO2, and lactate release in the leg during exercise. These data suggest that during exercise in patients with heart failure, the sympathetic nervous system helps to sustain arterial blood pressure and that this beneficial effect is not associated with adverse effects on blood flow to working skeletal muscle.     

Epicardial activation of the human ventricle: Effects of left ventricular hypertrophy

To determine the effects of left ventricular hypertrophy on eplcardlal activation of the human heart, Intraoperative eplcardlal mapping of 40 to 66 points was performed In 10 patients undergoing aortic valve replacement. Mean calculated left ventricular mass was 364 ± 98 g. All patients had normal left ventricular contraction. Earliest eplcardlal activation occurred In the anterior right ventricle In all patients. In 9 patients, it was the only eplcardlal breakthrough point. One patient had a single Inferior left ventricular breakthrough point. Eplcardlal activation spread from the right ventricle towards the left ventricle in both the anterior and inferior direction. Latest eplcardlal activation occurred at the base of the left ventricle In 9 patients and the base of the right ventricle In 1.When compared with patients with coronary artery disease, normal ventricular contraction, and no left ventricular hypertrophy, patients with hypertrophy had fewer left ventricular breakthrough points (p <0.001) and were more likely to have latest activation at the left ventricular base (p <0.001).We conclude that left ventricular hypertrophy Is associated with marked changes In the pattern of epicardlal activation. These changes may reflect delay In spread from endocardium due to the increased wall thickness.