By X. Kliff. University of Baltimore. 2018.
Persistent pulmonary hypertension – pulmonary hypertension and vascular hyperreactivity with resultant right to left shunting and cyanosis discount fluticasone 250 mcg otc; associated with cardiac anomalies purchase 100mcg fluticasone with mastercard, respiratory distress syndrome, meconium aspiration syndrome, diaphragmatic hernia, and group B streptococcal sepsis. Gastroesophageal reflux – involuntary movement of stomach contents into the esophagus; physiologic reflux is found in all newborns; pathologic reflux can result in failure to thrive, recurrent respiratory problems/aspiration, bronchospasm, and apnea, irritability, esophagitis, ulceration and gastrointestinal bleeding. Jaundice – hyperbilirubinemia from increased bilirubin load and poor hepatic conjugation/unconjugated, physiologic/ or abnormalities of bilirubin production, metabolism, or excretion/non-physiologic/. Hypoglycemia – blood sugar less than 40 mg/100ml, characterized by lethargy, hypotonia, tremors, apnea, and seizures. Premedication The primary goals of premedication in children are to facilitate a smooth separation from the parents and to ease the induction of anesthesia. Other effects that may be achieved by premedication include: Amnesia Anxiolysis Prevention of physiologic stress Reduction of total anesthetic requirements Decreased probability of aspiration Vagolysis Decreased salivation and secretions Antiemesis Analgesia Children greater than 10 months usually receive midazolam 0. The circuits used for pediatrics were traditionally designed specifically to decrease the resistance to breathing by eliminating valves; decrease the amount of dead space in the circuit; and in the case of the Bain circuit, decrease the amount of heat loss by having a coaxial circuit with warm exhaled gas surrounding and warming the fresh gas flow. Airways: To determine whether an oral airway is the proper size, hold the airway beside the patient’s face with the top of the airway beside the mouth. It is less bulky, allowing laryngoscopy to be performed while cricoid pressure is applied with the fifth finger of the same hand. In general straight blades/Miller/ are used in infants to facilitate picking up the elongated epiglottis and exposing the vocal cords. Endotracheal tubes: small-diameter endotracheal tubes increase airway resistance and work of breathing. The anesthesiologist should calculate ideal tube size and have available one size larger and one size smaller. Ultimately the proper tube size is confirmed by the ability to generate positive pressure greater than 30 cm H2O and by the presence of a leak at less than 20 cm H2O. It is caused most often by inadequate depth of anesthesia with sensory stimulation /secretions, manipulation of airway, surgical stimulation/. Treatment includes removal of stimulus, 100% oxygen, continuous positive pressure by mask, and muscle relaxants. Usually laryngospasm will break under positive pressure but on the rare occasion that this fails, only a very small dose of succinylcholine is required for relaxation of the vocal cords, which are quite sensitive to muscle relaxation. While 1-2 mg/kg maybe required for complete relaxation, only one tenth of this will generally relax the vocal cords. Blood pressure monitoring: Cuff size can be determined using the following criteria: cuff bladder width should be approximately 40% of the arm circumference; bladder length should be 90 to 100% of the arm circumference. Invasive monitoring ( intraarterial catheters); Smaller catheters provide greater accuracy in monitoring, but larger are more practical for blood sampling. The consequences of thermal stress include cerebral and cardiac depression, increased oxygen demand, acidosis, hypoxia, and intracardiac shunt reversal. Use of the oximeter is particularly important in pediatrics because of the greater tendency of the infant to develop rapid desaturation and hypoxemia. The goal of neonatal oxygen monitoring is to maintain saturation in the low 90s to minimize risks of oxygen toxicity. In infants, two probes/preductal (right ear or right arm) and postductal (left arm or either leg) will reflect the amount of right to left shunting occurring. Also, while a patient may become noticeably cyanotic when the sat drops below 90%, there is no level of hypercarbia that is reliably clinically evident. Factors that increase West’s Zone I of the lungs (where alveolar pressure surpasses arterial pressure) will increase gradient. Such factors include hypovolemia (decreasing arterial pressure) and increased mean airway pressure (increasing alveolar pressure). Infants will not display head lift or respond to commands, even with full return of neuromuscular function. The facial nerve is not recommended as the orbicularis oculi muscle is more resistant to blockade and if one successfully blocks this muscle, the patient’s neuromuscular blockade may be unreversible. Also, direct muscle stimulation in this area may result in the administration of excessive amounts of relaxant. Small-gauge catheters are available for venous cannulation: 24G, 22G; a 25 or 27-gauge for very small premature infants. It will be much easier to administer medications and remove air from the intravenous system by using a separate stopcock and attaching it to a plain piece of extension tubing. Extensions for intravenous systems are particularly advisable as intravenous access is sometimes obtained in lower extremities. Fluids, electrolytes and transfusion therapy Preterm and small infants have a relatively high percentage of total body water/85% in a preterm and 75% in a full-term infant/. Generally either lactated Ringer’s or normal saline is used for routine intraoperative fluid administration. Glycogen stores in the neonatal liver are limited and are rapidly depleted within the first few hours of life. Preterm infants may be hypoglycemic without demonstrable symptoms, necessitating close monitoring of blood glucose levels. Hypoglycemia is defined in full-term infants as a serum glucose concentration less than 30mg/100ml in the first day of life or less than 40 mg/100ml in the second day of life.
The H274Y mutation in the influenza A/H1N1 neu- raminidase active site following oseltamivir phosphate treatment leave virus severely compromised both in vitro and in vivo discount fluticasone 250mcg line. Oral oseltamivir improves pulmonary function and reduces exacerbation frequency for influenza-infected children with asthma buy fluticasone 250 mcg on line. Impact of oseltamivir treatment on influenza-related lower respiratory tract complications and hospitalizations. Factors influencing the effectiveness of oseltamivir and amantadine for the treatment of influenza: a multicenter study from Japan of the 2002-2003 influenza season. Transmission of H7N7 avian influenza A virus to human beings during a large outbreak in commercial poultry farms in the Netherlands. A multicentre, randomized, controlled trial of oseltamivir in the treatment of influenza in a high-risk Chinese population. Adverse effects of amantadine and oseltamivir used during respiratory outbreaks in a center for developmentally disabled adults. Neuraminidase sequence analysis and susceptibilities of influenza virus clinical isolates to zanamivir and oseltamivir. Pharmacokinetics and dosage recommendations for an oseltamivir oral suspension for the treatment of influenza in children. Long-term use of oseltamivir for the pro- phylaxis of influenza in a vaccinated frail older population. Economic evaluation of osel- tamivir phosphate for postexposure prophylaxis of influenza in long-term care facilities. Management of influenza in adults older than 65 years of age: cost-effectiveness of rapid testing and antiviral therapy. Influenza treat- ment with neuraminidase inhibitors Cost-effectiveness and cost-utility in healthy adults in the United Kingdom. Lack of effect of moderate hepatic impairment on the pharmacokinetics of oral oseltamivir and its metabolite oseltamivir carboxylate. Efficacy and safety of the oral neuramini- dase inhibitor oseltamivir in treating acute influenza: a randomized controlled trial. Effectiveness of oseltamivir in preventing influ- enza in household contacts: a randomized controlled trial. Neuraminidase inhibitor-resistant influenza viruses may differ substantially in fitness and transmissibility. Virulence may determine the neces- sary duration and dosage of oseltamivir treatment for highly pathogenic A/Vietnam/1203/04 influenza virus in mice. M2 inhibitors block the ion channel formed by the M2 protein that spans the viral membrane (Hay 1985, Sugrue 1991). Thereafter, acidification of the endocytotic vesicles is required for the dissociation of the M1 protein from the ribonucleoprotein com- plexes. The drug is effective against all influenza A subtypes that have previously caused disease in humans (H1N1, H2N2 and H3N2), but not against influenza B virus, because the M2 protein is unique to influenza A viruses. Rimantadine is not active against the avian flu subtype H5N1 strains that have recently caused disease in hu- mans (Li 2004). For both the prevention and treatment of influenza A, rimantadine has a comparable efficacy to amantadine but a lower potential for causing adverse effects (Stephenson 2001, Jefferson 2004). The development of neutralising antibodies to influenza strains seems not to be af- fected by rimantadine. However, the presence of IgA in nasal secretions was sig- nificantly diminished in one study (Clover 1991). A recently published study revealed an alarming increase in the incidence of aman- tadine-resistant and rimantadine-resistant H3N2 influenza A viruses over the past decade. In a recently published study, which assessed more than 7,000 influenza A viruses obtained worldwide from 1994 to 2005, drug resistance against amantadine and rimantadine increased from 0. Viruses collected in 2004 from South Korea, Taiwan, Hong Kong, and China show drug-resistance fre- quencies of 15 %, 23 %, 70 %, and 74 %, respectively. Some authors have sug- gested that the use of amantadine and rimantadine should be discouraged (Jefferson 2006). The single dose elimination half-life is about 30 hours in both adults (Hayden 1985) and children (Anderson 1987). Following oral administration, ri- mantadine is extensively metabolised in the liver and less than 25 % of the dose is excreted unchanged in the urine. However, a study on the safety and efficacy of prophylactic long-term use in nursing homes showed no statistically significant differences in the frequencies of gastrointestinal or central nervous system symptoms between treat- ment and placebo groups (Monto 1995). Rimantadine 209 Rarely, seizures may develop in patients with a history of seizures, who are not re- ceiving anticonvulsant medication. The safety and pharmacokinetics of rimantadine in renal and hepatic insufficiency have only been evaluated after single-dose administration. Because of the potential for accumulation of rimantadine and its metabolites in plasma, caution should be exercised when treating patients with renal or hepatic insufficiency. Likewise, rimantadine should not be administered to nursing mothers because of the adverse effects noted in the offspring of rats treated with rimantadine during the nursing period. Comparative studies indicate that rimantadine is better tolerated than amantadine at equivalent doses (Jefferson 2004).
While family studies should control for strain differences fluticasone 100mcg discount, the small effects of multiple genes would only be found if very large numbers of families were studied buy discount fluticasone 250mcg line, and the most important genes may vary from family to family. To further complicate the analysis, the concor- dance rate in twin studies was, at most, about 50 % – so identical genes may not yield identical results at least half the time. Given the differences in the strain virulence and exposure within a population, and the genetic heterogeneity and apparent incomplete penetrance of the responsible genes, it should not be surprising that it is difficult to obtain clear, reproducible associations with specific alleles, even those that may have moderate effects. While documenting or quantifying exposure to the bacillus, or strain virulence, may be difficult, their roles in pathogenesis are obvious. In contrast, environmental influences are not only difficult to document and quantify (Lienhardt 2001), but their effects have not been well studied and are poorly understood. He compared two groups of infected rabbits: five animals were free to roam outdoors with ample food, while another five were kept in dark cages with minimal food. The reasons for the difference - poor nutrition (Chan 1996, Dubos 1952), crowded liv- ing conditions, or emotional stress (Stansfeld 2002) - and the mechanism of their effects on the immune system, are unclear. Before the war, in 1913, the rates were 118 and 142/100,000 for Bel- gium and the Netherlands, respectively, but by 1918, the rates had increased to 245 and 204/100,000 (Rich 1951). It may be difficult to separate these factors however, because deteriorating and traumatic social conditions are often accompanied by a collapse of the healthcare system. Given that susceptibility seems to be determined by a complex interplay of strain virulence, intensity of exposure and environmental factors, as well as human genetic composition, would it be feasible or advisable to target vaccines, prophylaxis, treatment, or control efforts based on the genetic composition of individuals, families or ethnic groups, instead of simply improving control programs (and socioeconomic status, although more difficult) for the entire population? Might it be more efficient and less costly simply to concentrate on diagnosing and effectively treating cases, and using extra funds for contact tracing? In light of the continuing presence of multi-drug resistant strains (Raviglione 2006), and the difficulties in finding and bringing new drugs and vac- cines into clinical use, further investigation in the field may be justified, despite the relatively disappointing results obtained so far. Acknowledgements: The author thanks Laurent Abel and Luis Quintana-Murci for enlight- ening discussions, Peter Taylor, Zulay Layrisse, Mercedes Fernandes, Angel Villasmil, Gustavo López, Warwick Britton, Joanne Flynn, Stewart Cole and Marisa Gonzatti for critical readings, and especially Pedro Alzari and Stewart Cole for many valuable discus- sions, as well as training, support and encouragement. Toll-like receptor 4 expression is required to control chronic Mycobacterium tuberculosis infection in mice. No association between interferon- gamma receptor-1 gene polymorphism and pulmonary tuberculosis in a Gambian population sample. Tuberculosis and chronic hepatitis B virus infection in Africans and variation in the vitamin D receptor gene. Assessment of the interleukin 1 gene cluster and other candidate gene polymorphisms in host susceptibility to tuberculosis. Mannose binding protein deficiency is not associated with malaria, hepatitis B carriage nor tuberculosis in Africans. Toll-like receptor 2 Arg677Trp polymorphism is associated with susceptibility to tuberculosis in Tunisian pa- tients. Genetics of host resistance and susceptibility to intramacrophage patho- gens: a study of multicase families of tuberculosis, leprosy and leishmaniasis in north- eastern Brazil. Vitamin D receptor polymorphisms and susceptibility to tuberculosis in West Africa: a case-control and family study. The host resistance locus sst1 controls innate immunity to Listeria monocytogenes infection in immunodeficient mice. Tuberculosis in sub-Saharan Africa: a regional assessment of the impact of the human immunodeficiency virus and National Tuberculosis Control Program quality. Fine mapping of a putative tuberculosis- susceptibility locus on chromosome 15q11-13 in African families. Interferon-gamma gene (T874A and G2109A) polymorphisms are associated with microscopy-positive tuberculosis. Gene dosage determines the negative effects of polymorphic alleles of the P2X7 receptor on adenosine triphosphate-mediated killing of mycobacteria by human macrophages. Large-scale candidate gene study of tuberculo- sis susceptibility in the Karonga district of northern Malawi. A functional promoter polymor- phism in monocyte chemoattractant protein-1 is associated with increased susceptibility to pulmonary tuberculosis. Surfactant protein genetic marker alleles identify a subgroup of tuberculosis in a Mexican population. The molecular epidemiology of tuberculosis in New York City: the importance of nosocomial transmission and labo- ratory error. A polymorphism in Toll-interleukin 1 receptor domain containing adaptor protein is associated with susceptibility to meningeal tuber- culosis. Cytokine gene polymorphisms in Colombian patients with different clinical presentations of tuberculosis. Risk factors for transmission of Mycobacte- rium tuberculosis in a primary school outbreak: lack of racial difference in susceptibility to infection.
The commonest cause of intracerebral haemorrhage is hypertension purchase fluticasone 250 mcg mastercard, but other causes should be considered including underlying structural abnormalities (e generic fluticasone 500 mcg on line. The 30-day mortality is higher in deep haemorrhages than lobar, and increases with increasing volume of bleed. Patients with cerebellar haematoma are at particular risk of deterioration, specifically direct compression of the brain stem and cerebellum, and hydrocephalus. The surgical evacuation of haematoma has been used in selected patients and recently subjected to randomised controlled trial. The clinical question is which patients with primary intracerebral haemorrhage should be referred for surgical evacuation. Patients were admitted to the trial if the neurosurgeon felt there was equipoise regarding the benefits of either treatment. Patients were eligible if the haematoma was greater than 10 cu cm and the interval between stroke and start of treatment was less than 48 hours. Only univariate analyses were reported and this combined with the small sample size limits the generalisability of these results. None of the endoscopically treated patients were reported to have died from a surgically related complication. At 6 months, the mortality rate was significantly lower in the surgically treated patients compared with those treated medically (42 vs 70%; p<0. In this study, 25% of the patients who were randomised for conservative therapy later went on to have surgery. There were no papers identified in the evidence review which specifically addressed hydrocephalus in association with intracerebral haemorrhage. There was no strong evidence on which to set an age threshold above which surgery should not be considered. The consensus of the group was that previously fit patients with a lobar haemorrhage with hydrocephalus, or those who are deteriorating neurologically where draining of the haematoma might improve outcome should be referred for surgery. However, the consensus was that patients with cerebellar haematoma should be carefully and regularly monitored for changes in neurological status that might indicate the development of coning or hydrocephalus by specialists in neurosurgical or stroke care. R58 People with intracranial haemorrhage should be monitored by specialists in neurosurgical or stroke care for deterioration in function and referred immediately for brain imaging when necessary. R59 Previously fit people should be considered for surgical intervention following primary intracranial haemorrhage if they have hydrocephalus. It has a mortality rate of 80%192 and usually presents within 2–5 days of stroke onset. There have been a number of reports of benefit from decompressive hemicraniectomy, but concerns remain as to the benefits in terms of both survival and good clinical outcome. Neurosurgeons in many centres have been reluctant to operate partly because of their experiences of hemicraniectomy in other conditions. Poor outcomes may be related to late referral of patients when surgery is performed after brain damage has become irreversible. Timely referral is vital to ensure that intervention takes place before damage is irreversible. The clinical question is which patients with malignant middle cerebral artery infarction should be referred for surgery. Data were included only for patients aged 18 to 60 years treated within 48 hours of randomisation. Level 1++ One systematic review (12 retrospective and prospective case series) (N=138 (129 plus nine patients added from the authors’ own institution) reported a pooled analysis of the outcomes associated with decompressive surgery. A dictomotimised outcome score was used with a good outcome defined as functional independence or mild to moderate disability and a poor outcome as severe disability or death. The mortality rate was also significantly higher after surgery in patients older than 50 years compared with those 50 years or less. The consensus of the group was that those patients identified in the pooled analysis 111 Stroke study194 should be referred for decompressive hemicraniectomy. The evidence base supports the use of decompressive hemicraniectomy up to the age of 60. The meta-analysis showed that there is a significant increase in morbidity in patients over 50 years old, which suggests added caution is needed in selecting patients over 50 years for hemicraniectomy. It should be noted that the evidence relates only to patients under the age of 60 years; this condition is not seen in older people probably because with the inevitable loss of brain volume with age, there is additional intracranial space to accommodate oedema with cerebral infarction. The data from a large non-randomised series suggested that outcome is substantially improved if treatment is initiated within 24 hours of stroke onset as compared to longer time windows for treatment. The pooled analysis took into account patients referred up to 45 hours, but the consensus of the group was that the prospective studies suggest that earlier referral is associated with better outcome. It is vital that patients at risk of malignant middle cerebral artery infarction are identified early, undergo careful, regular neurological monitoring by specialists in stroke or neurosurgical care, and deteriorating patients are referred immediately to a neurosurgical centre. R62 People who are referred for decompressive hemicraniectomy should be monitored by appropriately trained professionals, skilled in neurological assessment. Does modified-release dipyridamole or clopidogrel with aspirin improve outcome compared with aspirin alone when administered early after acute ischaemic stroke? How safe and effective is very early mobilisation delivered by appropriately trained professionals after stroke?