Postural dysautonomia in response to head-up tilt in a military pilot aspirant: Aeromedical considerations

Intolerance to orthostasis encompasses a group of responses on assumption of upright posture. One such response is postural dysautonomia. One of the types of postural dysautonomia is postural orthostatic tachycardia syndrome, which is characterised by an increase in heart rate of more than 30 bpm without hypotension along with other features of dysautonomia on attaining an erect posture, either actively or passively. This paper brings out a case of postural dysautonomia in a pilot aspirant in response to Head-up tilt (HUT) test. A 23-year-old female military pilot aspirant reported for evaluation of Syncope and Air Sickness. She gave a history of solitary episode of loss of consciousness on ground while preparing for an early morning sortie. She was diagnosed with a case of neurocardiogenic syncope and was put back to flying training. Subsequently, after about 2 months, she developed features of air sickness while flying and also could not tolerate preliminary motion sickness desensitisation at her unit. A thorough medical evaluation failed to reveal any neurocardiological abnormality. Before commencing the air sickness desensitisation protocol at the Institute of Aerospace Medicine, she was subjected to HUT during which she developed signs and symptoms suggestive of postural dysautonomia. A test retest assessment with repeat HUT and passive standing test revealed similar responses.

A simulation study to compare physiological responses to hypoxia and exercise between anaemic subjects and healthy controls

Objectives: Military flying is a complex task and requires high level of physical fitness of aviators. Various aviation stressors such as acceleratory force, hypoxia, cold weather conditions and decompression sickness place enormous stress on human physiological systems of the aviators. Individuals with Hb <13 g/dL (males) are being placed in the lower medical category which makes them unfit to fly. The present study was undertaken to assess the implication of low haemoglobin (Hb) on exercise capacity and hypoxia tolerance. Materials and Methods: Twenty-five individuals with anaemia and 15 healthy controls participated in the study. The participants were subjected to normobaric hypoxia (NH) equivalent to an altitude of 15,000 feet. Different physiological parameters such as heart rate (HR), systolic and diastolic blood pressure (SBP and DBP), respiratory rate (fR) and arterial oxygen saturation (SpO2) were measured during NH. Participants also performed maximal aerobic capacity (V?O2 max) and maximal anaerobic capacity test in bicycle ergometer. Results: HR, SBP, DBP and fR in anaemic subjects were higher than healthy controls during NH, whereas SpO2 in anaemic subjects was lower as compared to healthy controls. Anaemic individuals had a lower VO2 max than their healthy counterparts. Critical power and anaerobic work capacity were lower in anaemic subjects than healthy controls. Conclusion: There is a deterioration in exercise capacity and hypoxia tolerance in individuals with low Hb levels. Adequate precaution should be exercised for permitting military aviators to fly with low Hb level.

Clonal clusters and virulence factors of methicillin-resistant Staphylococcus Aureus: Evidence for community-acquired methicillin-resistant Staphylococcus Aureus infiltration into hospital settings in Chennai, South India

Background and Objective: Staphylococcus aureus is one of the major pathogens of nosocomial infections as wells as community-acquired (CA) infections worldwide. So far, large-scale comprehensive molecular and epidemiological characterisation of S. aureus from very diverse settings has not been carried out in India. The objective of this study is to evaluate the molecular, epidemiological and virulence characteristics of S. aureus in both community and hospital settings in Chennai, southern India. Methods: S. aureus isolates were obtained from four different groups (a) healthy individuals from closed community settings, (b) inpatients from hospitals, (c) outpatients from hospitals, representing isolates of hospital–community interface and (d) HIV-infected patients to define isolates associated with the immunocompromised. Antibiotic susceptibility testing, multiplex polymerase chain reactions for detection of virulence and resistance determinants, molecular typing including Staphylococcal cassette chromosome mec (SCCmec) and agr typing, were carried out. Sequencing-based typing was done using spa and multilocus sequence typing (MLST) methods. Clonal complexes (CC) of hospital and CA methicillin-resistant S. aureus (MRSA) were identified and compared for virulence and resistance. Results and Conclusion: A total of 769 isolates of S. aureus isolates were studied. The prevalence of MRSA was found to be 7.17%, 81.67%, 58.33% and 22.85% for groups a, b, c and d, respectively. Of the four SCCmec types (I, III, IV and V) detected, SCCmec V was found to be predominant. Panton-Valentine leucocidin toxin genes were detected among MRSA isolates harbouring SCCmec IV and V. A total of 78 spa types were detected, t657 being the most prevalent. 13 MLST types belonging to 9 CC were detected. CC1 (ST-772, ST-1) and CC8 (ST238, ST368 and ST1208) were found to be predominant among MRSA. CA-MRSA isolates with SCCmec IV and V were isolated from all study groups including hospitalised patients and were found to be similar by molecular tools. This shows that CA MRSA has probably infiltrated into the hospital settings.

Sphenoid sinus mucocele with blindness: a rare presentation.

Isolated sphenoid sinus mucocele is a rare entity. Here we report a case of isolated sphenoid sinus mucocele in a 9 years old girl presenting with unilateral blindness and without any sinonasal complaints. C.T. scan revealed an isolated sphenoid sinus mucocele which was managed endoscopically. A brief review of literature is also included.

Myiasis infestation in postoperative mastoid cavity.

This is a case report of myiasis in modified radical mastoidectomy cavity in a 48 years old male presented in the Department of ENT and Head and Neck Surgery, T.U.Teaching Hospital, Katmandu, Nepal. Around 50 maggots were removed from his mastoid cavity. Patient was managed with turpentine oil and antibiotics which was given to prevent secondary infection. Literature search revealed only one case report of Myiasis infestation in a postoperative mastoid cavity.

OK-432: an effective sclerosing agent for the treatment of lymphangiomas of head and neck.

OBJECTIVE: The basic objective of this study was to find out the efficacy of OK-432 for the conservative treatment of lymphangiomas of head and neck regions at the Department of ENT-Head & Neck Surgery of Tribhuvan University Teaching Hospital (TUTH), Kathmandu, Nepal. METHODS: It was a hospital based prospective, cross-sectional, case series, conducted among the patients suffering from different lymphangiomas of head and neck regions and treated with intra-lesional injection of OK-432, from March, 2005 to September 2006. Altogether eleven patients were enrolled in this modality of treatment out of which one patient was excluded from the study, which was treated surgically due to very ugly scar at the site of lesion resulting from previous surgery for the same. The data were analyzed by using simple mathematical tools like percentage and frequency. RESULTS: Out of ten patients treated with intralesional injection of OK-432, absolute response, i.e. total resolution of swelling was found in nine patients (90%) after the first dose. Remaining one patient also responded well on the treatment but some residual swelling was in situ for which second dose was given. After the second dose it was also totally resolved. In this way we achieved 100% response after the second dose of OK-432. CONCLUSION: The results of this study so far indicate that OK-432 is an effective and safe tool for the treatment of lymphangioma of head and neck region. As the procedure can be done in an out patient department, without hospitalization and has got minimal side effects, it can be proposed as the first line treatment of lymphangiomas of head and neck.

Hearing results after myringoplasty.

BACKGROUND: Myringoplasty is one of the various surgical techniques for the management of chronic supurative otitis media of tubotympanic type (CSOM-TT). The presence of a perforation of tympanic membrane with intermittent discharge and hearing loss of conductive nature are the indications of myringoplasty. It is a beneficial procedure done for closing tympanic membrane perforation and improving hearing. OBJECTIVE: The aim of this study was to assess hearing improvement after myringoplasty within ten weeks following surgery. MATERIAL AND METHODS: The study population consisted of 50 patients who were suffering from CSOM-TT. Preoperative and postoperative examinations of the patients were conducted clinically as well as audiologically. Pre and postoperative air-bone (A-B) gap were calculated by taking the averages of bone conduction and air conduction at the frequencies of 500, 1000 and 2000 Hz. Myringoplasty was performed with underlay technique under local anaesthesia by either permeatal or endaural approach. Temporal muscle fascia was used as grafting material for reconstruction of the tympanic membrane. RESULTS: Preoperatively, air-bone gap of 30 db or more was observed in 39 (76%) patients whereas post operatively A-B gap of 30 db or more was observed in only one patient. Using hearings gain exceeding 15 dB as the criterion, thirty-nine (78%) patients had their hearing gain exceeding 15 dB. Using postoperative A-B gap within 20 dB as the criterion, 42 (84%) patients had their A-B gap within 20 dB. CONCLUSION: Myringoplasty is a beneficial procedure for hearing improvement. Using the proportion of patients with a postoperative A-B gap of 30 dB as the criterion, in this study, 98% of patients achieved their A-B gap closer within 30 dB. Using hearing gain exceeding 15 dB as the criterion, 78% patient had their hearing gain exceeding 15 dB.

Distribution of malignancies in head and neck regions and their management.

A retrospective, cross sectional, series of cases were currently studied in the department of ENT-Head & Neck Surgery of Tribhuvan University Teaching Hospital (TUTH) Kathmandu, Nepal to find out the distribution of different malignancies in head and neck regions and to identify their treatment modalities during the period of one year from January 2003 to December 2003. Altogether 159 new cases of histopathologically/cytopathologically confirmed malignancies of head and neck regions and their treatment modalities were analyzed. Out of 159 cases, malignancies of larynx (41), pharynx (31) and oral cavity (30) were found to be the commonest head and neck malignancies where as malignancies of ear (1), and salivary glands (4) were found to be the least common. Likewise surgery with or without radiotherapy and/or chemotherapy was found to be the commonest treatment modality. Of the 159 cases seven were occult primary. As the laryngo-pharyngo-oral malignancies are the commonest malignancies and surgery with or without radiotherapy and/or chemotherapy the commonest treatment modalities for these head and neck malignancies. A well equipped head and neck unit is needed at TUTH along with proposed radiotherapy and medical oncology support for better management of these malignancies.

Lipoblastoma in head and neck--a rare childhood tumour.

Lipoblastoma is an uncommon benign mesenchymal tumour that occurs primarily in children younger than 3 yrs of age. Despite the lesions being benign, great difficulty can be encountered in its management because of its tendency to invade the different fascial planes. A rare case of huge lipoblastoma diagnosed in a 22 months old child, involving various spaces of face and skull base has been reported. This huge tumour was completely and successfully removed through cheek incision without any postoperative complications.

Energy cost and cardiorespiratory changes during the practice of Surya Namaskar.

Surya Namaskar (SN), a group of Yogic exercise consists of a set of twelve postures which is practiced by some of the yoga practitioners. The present study was undertaken to observe critically the energy cost and different cardiorespiratory changes during the practice of SN. Twenty-one male volunteers from the Indian Army practiced selected Yogic exercises for six days in a week for three months duration. The Yogic practice schedule consisted of Hatha Yogic Asanas (28 min), Pranayama (10.5 min) and Meditation (5 min). In the Yogic practice schedule 1st they practiced Kapal Bhathi (breathing maneuvers) for 2 min then Yogamudra (yogic postural exercise) for 2 min, after that they took rest until oxygen consumption and heart rate (HR) came to resting value. Subsequently subjects performed SN for 3 min 40 seconds on an average. After three months of training at the beginning of the fourth month subjects performed entire Yogic practice schedule in the laboratory as they practiced during their training session and experiments were carried out. Their pulmonary ventilation, carbondioxide output, Oxygen consumption, HR and other cardiorespiratory parameters were measured during the actual practice of SN. Oxygen consumption was highest in the eighth posture (1.22+/-0.073 1 min(-1)) and lowest in the first posture (0.35+/-0.02 1 min(-1)). Total energy cost throughout the practice of SN was 13.91 kcal and at an average of 3.79 kcal/min. During its practice highest HR was 101+/-13.5 b.p.m. As an aerobic exercise SN seemed to be ideal as it involves both static stretching and slow dynamic component of exercise with optimal stress on the cardiorespiratory system.

Aerobic capacity & perceived exertion after practice of Hatha yogic exercises.

BACKGROUND & OBJECTIVES: Reports on the effect of yogic exercises on aerobic capacity are few. There is also no literature available on the effect of yogic exercise on perceived exertion (PE) after maximal exercise. In this study the effect of training in Hatha yogic exercises on aerobic capacity and PE after maximal exercise was observed. METHODS: Forty men from the Indian army (aged 19-23 yr) were administered maximal exercise on a bicycle ergometer in a graded work load protocol. The oxygen consumption, carbon dioxide output, pulmonary ventilation, respiratory rate, heart rate (HR) etc., at maximal exercise and PE score immediately thereafter were recorded. The subjects were divided into two equal groups. Twelve subjects dropped out during the course of study. One group (yoga, n = 17) practiced Hatha yogic exercises for 1 h every morning (6 days in a week) for six months. The other group (PT, n = 11) underwent conventional physical exercise training during the same period. Both groups participated daily in different games for 1 h in the afternoon. In the 7th month, tests for maximal oxygen consumption (VO2Max) and PE were repeated on both groups of subjects. RESULTS: Absolute value of VO2Max increased significantly (P < 0.05) in the yoga group after 6 months of training. The PE score after maximal exercise decreased significantly (P < 0.001) in the yoga group after 6 months but the PT group showed no change. INTERPRETATION & CONCLUSION: The practice of Hatha yogic exercises along with games helps to improve aerobic capacity like the practice of conventional exercises (PT) along with games. The yoga group performed better than the PT group in terms of lower PE after exhaustive exercise.