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±10.8 per cent for all patients with HAPE. Higher SpO2values were achieved with PRM in comparison to Hudson's mask on day one (86.08±5.15 vs. 77.23±9.09%) and day two (89.94±2.96 vs. 83.39±5.93%). 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.

Anthropometric evaluation of school-going native highlanders (4-19 years of age) from the Leh-Ladakh region in India.

BACKGROUND: The native population of the Ladakh region faces the unique challenges of a high-altitude environment with distinct physiological adaptations in comparison with lowlanders. However, no comprehensive data on standard anthropometric parameters for the school-going children in this populace is available. OBJECTIVES: We aimed to study the various anthropometric parameters in the school-going native highlander population and computed measures of central tendency. The nutritional status of the community was also be determined by comparing with World Health Organization (WHO) scores for height for age (HFA), weight for age (WFA) and body mass index (BMI) for age. DESIGN: A cross-sectional, descriptive study was devised to assess the anthropometric parameters. We measured height, weight, mid-upper circumference (MUAC), triceps skinfold (TSF) thickness, sub-scapular skinfold (SSF) thickness, waist, hip and abdominal circumference. Statistical analysis was conducted to determine the mean [±2 standard deviation (SD)], median, range, minimum and maximum. The z-scores for HFA, WFA and BMI for age was computed using WHO reference data. SUBJECTS: A total of 346 school-going native highlander children (4-19 years of age) were studied. RESULTS: Among the study population, the mean height was 141.17 ± 39.08 cm, the mean weight was 38.27 ± 25.40 kg. The gender difference in height, MUAC, sub-scapular skinfold (SSF) thickness, TSF thickness and the abdominal circumference was found to be statistically significant. Of the subjects 23.46% were stunted (i.e. HFA below -2 SD of the WHO standard) and 7.01% were underweight (WFA below -2 SD of the WHO standard). CONCLUSION: The nutritional status of the Ladakhi population was assessed by comparison with the WHO reference data. Nomograms for anthropometric data in school-going children (4-19 years of age) of Ladakh were created. These can be used for further studies and planning targeted intervention strategies on this geographically isolated and evolutionary distinct highland population.

Comparison of Optic Nerve Sheath Diameter between both eyes: A Bedside Ultrasonography Approach.

CONTEXT: Optic nerve sheath diameter (ONSD) has long been accepted as a reliable proxy of intracranial pressure especially in critical care and bedside settings. The present consensus is to measure ONSD in both eyes and take average value, which is cumbersome and a potential cause of discomfort to the patient. AIM: We aim to compare the values of ONSD of the right and left eye in a random sample as measured by bedside ocular ultrasonography (USG) in Indian adults. SETTINGS AND DESIGN: This was a prospective study conducted from September 2012 to March 2013 in the Department of Internal Medicine of a tertiary care hospital situated at moderate high altitude (11,500 ft) in India. MATERIALS AND METHODS: Patients admitted with high altitude pulmonary edema (HAPE) were recruited by convenience sampling. The ONSD of both eyes were measured 3 mm behind the globe using a 7.5 MHz linear probe on the closed eyelids of supine subjects. STATISTICAL ANALYSIS: Analysis was done using SPSS 17.0. RESULTS: A total of 47 patients of HAPE were recruited to the study with daily ONSD recording of both eyes during the admission period. The mean ONSD of the left eye was 4.60 (standard deviation [SD] = 0.71) whereas the mean ONSD of right eye 4.59 (SD = 0.72). The ONSD of the right eye and left eye was strongly correlated (correlation coefficient = 0.98 with P < 0.0001). The mean difference in the ONSD of both eyes (right-left) was -0.0044 (SD = 0.11) which was not statistically significant (P = 0.533). CONCLUSION: Our results suggest that the difference in ONSD of both eyes is not statistically significant in disease or health. This study also suggests that the ONSD of either eye can be predicted by the other eye recordings. Based on these findings, it can be suggested that during ocular USG for routine bedside/research purposes it is sufficient to measure ONSD of any of the one eye to save time and avoid discomfort to the patient.

Managing High-Altitude Pulmonary Edema with Oxygen Alone: Results of a Randomized Controlled Trial.

Yanamandra, Uday, Velu Nair, Surinderpal Singh, Amul Gupta, Deepak Mulajkar, Sushma Yanamandra, Konchok Norgais, Ruchira Mukherjee, Vikrant Singh, Srinivasa A. Bhattachar, Sagarika Patyal, and Rajan Grewal. High-altitude pulmonary edema management: Is anything other than oxygen required? Results of a randomized controlled trial. High Alt Med Biol. 17:294-299, 2016.-Treatment strategies for management of high-altitude pulmonary edema (HAPE) are mainly based on the observational studies with only two randomized controlled trials, thus the practice is very heterogeneous and individualized as per the choice of treating physician. To compare the response to different modalities of therapy in patients with HAPE in a randomized controlled manner. We conducted an open-label, randomized noninferiority trial to compare three modalities of therapy (Therapy 1: supplemental O2 with oral dexamethasone 8 mg q8 hours [n = 42], Therapy 2: supplemental O2 with sustained release oral nifedipine 20 mg q8 hours [n = 41], and Therapy 3: only supplemental O2 [n = 50]). Bed rest was mandated in all patients. The study was conducted in a cohort of previously healthy young lowlander males at an altitude of 3500 m. Baseline characteristics of the patients were comparable in the study arms. Complete response was defined as clinical and radiological resolution of features of HAPE, no oxygen dependency, a normal 6-minute walk test (6MWT) on 2 consecutive days, and normal two-dimensional echocardiography. Results were compared by analysis of variance using SPSS version 16.0. There was no statistical difference in duration of therapy to complete response between the three groups (Therapy 1: 8.1 ± 4.0 days, Therapy 2: 6.7 ± 3.9 days, Therapy 3: 6.8 ± 3.2 days; p = 0.15). There were no deaths in any of the groups. We conclude that oxygen and bed rest alone are adequate therapy for HAPE and that adjuvant pharmacotherapy with either dexamethasone or nifedipine does not hasten recovery.