Risk factors for postoperative complications in preterm infants with surgical necrotizing enterocolitis and associated outcomes.

BACKGROUND: We aim to determine clinical risk factors for postoperative complications in preterm infants with surgical necrotizing enterocolitis (NEC) or spontaneous intestinal perforation (SIP). METHODS: A retrospective cohort study of preterm infants with surgical NEC or SIP to compare clinical factors between those with and without postoperative complications. RESULTS: 78/109 (71.5%) infants had any complication following surgical NEC. Adhesions (20/35, 57.1%) and wound infection (6/35, 17.1%) were the most common single surgical complications. Patients with a single surgical complication (35/66, 53%) were significantly less likely to be exposed to antenatal steroids, more frequently had a jejunostomy, needed a central line longer, and had a longer length of stay than those without any surgical complication. Infants with > 1 surgical complication (43/71, 60.5%) included mainly females, and had AKI more frequently at NEC onset, lower weight z-scores and lower weight for length z- scores at 36 weeks PMA than those without any complications.On multinomial logistic regression, antenatal steroids exposure (OR 0.23 [CI 0.06, 0.84]; p = 0.027) was independently associated with lower risk and jejunostomy 4.81 (1.29, 17.9) was independently associated with higher risk of developing a single complication. AKI following disease onset (OR 5.33 (1.38, 20.6), P = 0.015) was independently associated with > 1 complication in surgical NEC/SIP infants. CONCLUSION: Infants with postoperative complications following surgical NEC were more likely to be female, have additional morbidities, and demonstrate growth failure at 36 weeks PMA than those without surgical complications. There was no difference in mortality between those with and without surgical complications.

Clinical determinants of intestinal failure and death in preterm infants with surgical necrotizing enterocolitis.

OBJECTIVE: We sought to investigate the clinical determinants of intestinal failure and death in preterm infants with surgical NEC. METHODS: Retrospective comparison of clinical information between Group A = intestinal failure (Parenteral nutrition (PN) >90 days) and death and Group B = survivors and with PN dependence < 90 days in preterm infants with surgical NEC. RESULTS: Group A (n = 99/143) had a lower mean gestational age (26.4 weeks [SD3.5] vs. 29.4 [SD 3.5]; p = 0.013), lower birth weight (873 gm [SD 427g] vs. 1425 gm [894g]; p = <0.001), later age of NEC onset (22 days [SD20] vs. 16 days [SD 17]; p = 0.128), received surgery later (276 hours [SD 544] vs. 117 hours [SD 267]; p = 0.032), had cholestasis, received dopamine (80.6% vs. 58.5%; p = 0.010) more frequently and had longer postoperative ileus time (19.8 days [SD 15.4] vs. 11.8 days [SD 6.5]; p = <0.001) and reached full feeds later (93 days [SD 45] vs. 44 [SD 22]; p = <0.001) than Group B.On multivariate logistic regression, higher birth weight was associated with lower risk (OR 0.35, 95% CI 0.15-0.82; p = 0.016) of TPN > 90 days or death. Longer length of bowel resected (OR 1.76, 95% CI 1.02-3.02; p = 0.039) and longer postoperative ileus (OR 2.87, 95% CI 1.26-6.53; p = 0.011) were also independently associated with TPN >90days or death adjusted for gestational age and antenatal steroid treatment. CONCLUSION: In preterm infants with surgical NEC, clinical factors such as lower birth weight, longer bowel loss, and postoperative ileus days were significantly and independently associated with TPN >90 days or death.

Mechanical work accounts for most of the energetic cost in human running.

The metabolic cost of human running is not well explained, in part because the amount of work performed actively by muscles is largely unknown. Series elastic tissues such as tendon can save energy by performing work passively, but there are few direct measurements of the active versus passive contributions to work in running. There are, however, indirect biomechanical measures that can help estimate the relative contributions to overall metabolic cost. We developed a simple cost estimate for muscle work in humans running (N = 8) at moderate speeds (2.2-4.6 m/s) based on measured joint mechanics and passive dissipation from soft tissue deformations. We found that even if 50% of the work observed at the lower extremity joints is performed passively, active muscle work still accounts for 76% of the net energetic cost. Up to 24% of this cost compensates for the energy lost in soft tissue deformations. The estimated cost of active work may be adjusted based on assumptions of multi-articular energy transfer, elasticity, and muscle efficiency, but even conservative assumptions yield active work costs of at least 60%. Passive elasticity can reduce the active work of running, but muscle work still explains most of the overall energetic cost.

Stepping onto the unknown: reflexes of the foot and ankle while stepping with perturbed perceptions of terrain.

Unanticipated variations in terrain can destabilize the body. The foot is the primary interface with the ground and we know that cutaneous reflexes provide important sensory feedback. However, little is known about the contribution of stretch reflexes from the muscles within the foot to upright stability. We used intramuscular electromyography measurements of the foot muscles flexor digitorum brevis (FDB) and abductor hallucis (AH) to show for the first time how their short-latency stretch reflex response (SLR) may play an important role in responding to stepping perturbations. The SLR of FDB and AH was highest for downwards steps and lowest for upwards steps, with the response amplitude for level and compliant steps in between. When the type of terrain was unknown or unexpected to the participant, the SLR of AH and the ankle muscle soleus tended to decrease. We found significant relationships between the contact kinematics and forces of the leg and the SLR, but a person's expectation still had significant effects even after accounting for these relationships. Motor control models of short-latency body stabilization should not only include local muscle dynamics, but also predictions of terrain based on higher level information such as from vision or memory.

Soft tissues store and return mechanical energy in human running.

During human running, softer parts of the body may deform under load and dissipate mechanical energy. Although tissues such as the heel pad have been characterized individually, the aggregate work performed by all soft tissues during running is unknown. We therefore estimated the work performed by soft tissues (N=8 healthy adults) at running speeds ranging 2-5 m s(-1), computed as the difference between joint work performed on rigid segments, and whole-body estimates of work performed on the (non-rigid) body center of mass (COM) and peripheral to the COM. Soft tissues performed aggregate negative work, with magnitude increasing linearly with speed. The amount was about -19 J per stance phase at a nominal 3 m s(-1), accounting for more than 25% of stance phase negative work performed by the entire body. Fluctuations in soft tissue mechanical power over time resembled a damped oscillation starting at ground contact, with peak negative power comparable to that for the knee joint (about -500 W). Even the positive work from soft tissue rebound was significant, about 13 J per stance phase (about 17% of the positive work of the entire body). Assuming that the net dissipative work is offset by an equal amount of active, positive muscle work performed at 25% efficiency, soft tissue dissipation could account for about 29% of the net metabolic expenditure for running at 5 m s(-1). During running, soft tissue deformations dissipate mechanical energy that must be offset by active muscle work at non-negligible metabolic cost.

A revolution in the making.

PIP: This paper reports on issues related to the Program of Action agreed upon by member countries at the 1994 UN International Conference on Population and Development held in Cairo, Egypt. It presents comments about the role of women in reproductive health excerpted from conversations with international theologians and activists. Ethical issues raised in these conversations centered around the rights of women in population and development--particularly in the area of reproductive health. The Cairo Program of Action called upon all governments to promote the empowerment of women and responsibility in men with respect to efforts to eliminate sex discrimination. The documentation produced at the Cairo conference is useful in campaigns aimed at alerting the government about the issues of the rights of women in empowerment, reproductive rights and health, and the development of the strength of nongovernmental organizations. Priority areas for the implementation of the Cairo principles were identified. The increasing impact of women in the international sphere, which began to become visible at the Cairo Conference, was seen by these activists as a significant development.^ieng

Suspected myocardial contusion. Triage and indications for monitoring.

Although many different tests are used to diagnose myocardial contusion, the clinical implications of the diagnosis are unclear. This makes it difficult to decide which patients require admission to a monitored bed. During 16 months, 3010 patients with blunt trauma were reviewed for evidence of sequelae attributable to myocardial contusion. None of 2204 admissions to unmonitored beds had evidence of serious arrhythmias or heart failure. No patient who died after admission had myocardial contusion at autopsy. Of the 644 admissions to monitored beds, 95 had workups for suspected contusion. Heart failure not obvious on admission did not occur and there were only four arrhythmias that required treatment. Conduction abnormalities on admission electrocardiogram predicted serious arrhythmias. Echocardiography and creatine phosphokinase isoenzyme levels, although frequently positive, did not predict morbidity. Clinically significant myocardial contusions are rare. Patients who will develop life-threatening complications from blunt cardiac injury can be identified in an emergency room setting.

Ankylosing hyperostosis of the spine: case report.

Ankylosing hyperostosis of the spine is described as osteophytic spurs or anterior osseous bridges with thickening of the corresponding vertebral cortex. The ossification includes the ligamentum longitudinale anterius and the peripheral part of the disc. Our patient had minor complaints but at the time of consultation was symptomatic.