High-altitude pulmonary oedema: Newer treatment modalities for an age-old problem

Background & objectives: High-altitude pulmonary oedema (HAPE) continues to challenge the healthcare providers at remote, resource-constrained settings. High-altitude terrain itself precludes convenience of resources. This study was conducted to evaluate the rise in peripheral capillary saturation of oxygen (SpO2) by the use of a partial rebreathing mask (PRM) in comparison to Hudson's mask among patients with HAPE. Methods: This was a single-centre, randomized crossover study to determine the efficiency of PRM in comparison to Hudson's mask. A total of 88 patients with HAPE referred to a secondary healthcare facility at an altitude of 11,500 feet from January to October 2013 were studied. A crossover after adequate wash-out on both modalities was conducted for first two days of hospital admission. All patients with HAPE were managed with bed rest and stand-alone oxygen supplementation with no adjuvant pharmacotherapy. Results: The mean SpO2on ambient air on arrival was 66.92�.8 per cent for all patients with HAPE. Higher SpO2values were achieved with PRM in comparison to Hudson's mask on day one (86.08�15 vs. 77.23�09%) and day two (89.94�96 vs. 83.39�93%). The difference was more pronounced on day one as compared to day two. Interpretation & conclusions: Mean SpO2values were found to be significantly higher among HAPE patients using PRM compared to those on Hudson's mask. Further studies to understand the translation of this incremental response in SpO2to clinical benefits (recovery times, mortality rates and hospital stay) need to be undertaken.

Changes in corneal thickness in patients with high-altitude pulmonary edema after systemic oxygen therapy

Purpose: High-altitude pulmonary edema (HAPO) is an acute medical emergency occurring typically in lowlanders, who ascend rapidly to heights of 3000 m or more. It presents with marked dyspnea on exertion, fatigue with minimal-to-moderate effort, prolonged recovery time, and dry cough with manifestations of cyanosis, tachycardia, tachypnea, and temperature which generally does not increase beyond 38.5°C. The condition may be fatal if not treated in time with supplemental oxygen or hyperbaric oxygen or rapid descent to lower altitude. There is paucity in literature on changes in corneal thickness in HAPO. The effect of continued oxygen therapy on corneal thickness has also not been studied in detail. Hence, this study was conducted at high altitude among physician-confirmed HAPO cases. Methods: A case–control study was conducted at an altitude of 11,400 feet. Cases were patients suffering from HAPO and controls were patients admitted in hospital for low back pain, fractures, and minor surgical procedures. Central corneal thickness (CCT) was measured with an ultrasound pachymeter on day 1 of hospitalization and every day of hospital stay. Systemic oxygen concentration was also measured daily. Results: There was no statistically significant difference in corneal thickness between two groups at the onset of illness, but a significant decrease in CCT was found in both right and left eyes in HAPO cases when oxygen levels were increased by giving supplemental oxygen. Hierarchical modeling showed a decrease in 1.3 ?m in CCT with one unit increase in oxygen mmHg in cases. Conclusion: The findings of statistically insignificant difference in CCT between HAPO cases and controls and a decrease in CCT in HAPO cases on being treated with systemic oxygenation are points to ponder about.

Pleomorphic adenoma of a subconjunctival ectopic lacrimal gland.

This report describes a case of pleomorphic adenoma of an ectopic lacrimal gland arising subconjunctivally in the lateral fornix in a 13-year-old girl. The tumor was removed surgically in toto with the capsule. This is probably the first reported case.

Comparative role of proteins in transport of HCH-isomers in desert locust, Schistocerca gregaria Forskal and bovines.

The studies on binding of hexachlorocyclohexane (HCH) with carrier proteins were carried out to establish the role of proteins in the transport of insecticides in insects. Sephadex G-200 column chromatography resolved haemolymph of adult male desert locust, Schistocerca gregaria into three major protein peaks. There was significant binding of gamma-HCH with first protein peak (F1). Two classes of binding sites were observed on first protein peak for gamma-HCH. However low level of binding was observed with the third protein peak (F3) of the haemolymph. Bindings of HCH-isomers (alpha, beta and gamma) with bovine serum albumin (BSA) were not related to their water solubilities. Moderate to low affinities (1.4 -1.84 x 10(6) M(-1)) of HCH-isomers for BSA were observed. The present studies showed that more HCH binds to haemolymph lipoprotein of locust as compared to BSA. This indicates a significant role of haemolymph proteins in the transport of insecticides in insects.

Insecticide interaction with carrier and neuroproteins.

Binding of alpha-, beta-, gamma-hexachlorocyclohexane, p,p'-DDT and p,p'-DDE with bovine serum albumin (BSA) and locust brain homogenate was studied. Binding affinities of pesticides were higher for the locust brain homogenates than for BSA. Results of uptake by isolated locust brain revealed higher uptake of gamma-HCH than alpha-HCH. gamma-HCH uptake was also higher from locust haemolymph than either from BSA or from buffer.

Isolation and characterization of the haemolymph lipoprotein of desert locust, Schistocerca gregaria Forskal.

A yellow lipoprotein was isolated and purified from haemolymph of desert locust, Schistocerca gregaria Forskal, by precipitation at low ionic concentration and by gel filtration. Sephadex G-200 resolved haemolymph into five protein peaks. First peak was of lipoprotein with molecular weight of 501,000 +/- 7000 (n = 3) and on electrophoresis, it separated into three bands. Maximum lipids from lipoprotein could be extracted with chloroform: methanol solvent system and were 52% by weight.