Introduction
The beauty of the mountains is ‘breathtaking’. They astound us not only with their grandiosity but also by drowning us through uneven pulmonary vasoconstriction. [1] High Altitude Pulmonary Edema (HAPE) does not reveal itself immediately because the pathophysiological changes begin early but progress through clinically silent phases. [2] It usually takes 2 to 5 days and an altitude above 3000m to manifest into its fullest form. [3, 4, 5, 6]. The mountain Gods consider haste as a sign of disrespect. A careless attempt to compete against time makes it difficult to escape their wrath of acute mountain sickness and HAPE. Over-exertion and ascending with respiratory tract infection further increase the chances of suffering. [7, 8]
The clinical features of HAPE share a close resemblance with pneumonia: cough (mostly productive), shortness of breath, fatigue, tachypnea, tachycardia, mild fever, and crepitation. Unfortunately, the locations where HAPE is initially recognized are usually extremely resource-limited: where clues from history and clinical examination form the backbone for making an accurate diagnosis. HAPE and pneumonia are comparable to monozygotic twins, where one takes the blame for another’s mischief. Diagnosis becomes more difficult when they both co-exist or are preceded by an upper respiratory tract infection. Ascent profile, duration of altitude exposure, and a previous history of HAPE provide major clues for a diagnosis favoring HAPE. However, in some rare cases of delayed onset HAPE, where the patient develops symptoms after staying at a particularly high altitude for more than 5 days, diagnosis of HAPE becomes a formidable task as alternative diagnoses must also be considered and ruled out.
Oxygenation is the cornerstone for the treatment of HAPE. This can be achieved either through increasing the pressure of inspired air (descent or Gamow bag) or through ventilation (preferably non-invasive). [8, 9, 10, 11] Temporary management with supplemental oxygen until the patient is stable enough to bear the exertion of descent by foot has been in practice in the Himalayan Rescue Association Aid Post. Over the years, this approach has been successful in the aid post. Here we present three unique cases of HAPE that do not show consistency with their usual natural history. We made the diagnosis based on clinical and ultrasonographic parameters using Point of Care Ultrasound (POCUS) (Butterfly iQ)
Clinical Case 1 (Delayed onset HAPE):
A 41 years male with a history of HAPE 13 years back had ascended from Lukla (2860m) to Everest Base Camp (5364 m) within a span of 4 days and had been residing in the Everest Base Camp. On the 11th day at the base camp, he started having shortness of breath, which lasted for 2 days before presenting to HRA Aid Post, Pheriche. A day after the onset of shortness of breath; he started having a productive cough with no fever or chest pain. He had no hypertension or prior medical illness and was not under any medications. The COVID-19 vaccine doses were uptodate as per recommendation but previous vaccination history could not be recalled. On examination, the patient was able to walk into the clinic and was well oriented to time, place and person. There were no signs of respiratory distress. A faint “gurgling” sound from the chest was audible without a stethoscope. His peripheral oxygen saturation was 53%, heart rate was 108min-1 and axillary temperature was 98.4 degrees Fahrenheit. His blood pressure was 125/80 mm Hg. There was no parasternal heave, pedal edema, hepatomegaly or elevation of JVP. Vocal fremitus was normal bilaterally. A dull percussion note was observed from the 5th intercostal space onwards anteriorly on the right side and from the 4th intercostal space onwards anteriorly on the left side. Auscultation revealed equal air entry along with inspiratory crackles and broncho-vesicular breath sounds in all the chest segments bilaterally. Heart sounds were normal. Ultrasonography of the lungs did not reveal any pleural collections, the lung sliding was normal. However, multiple B-lines with absent A-lines were seen in the anterior and lateral segments, most prominent in the anteroinferior and inferolateral segments. (Figure 1) The patient was given Nifedipine SR 20mg along with oxygen from an oxygen concentrator at 10 Lmin-1 for 3 hours, following which he got evacuated to a well-facilitated center. During his stay, his oxygen saturation improved from 53% to 91%. The patient apparently improved with treatment in a hospital for 4 days but could not be contacted following descent.
Clinical Case 2 (Early onset HAPE):
A 29 years lowlander male had been working as a porter in Namche for 2months, shifting loads up and down from Namche(3400m) to Pangboche(3800m). During a particular trip from
Namche, while he was carrying a heavy load from Pangboche (where he stayed a night on the way) to Thukla; at around 4500m, he started having persistent cough and shortness of breath that persisted on rest. He had no fever. His cough was frequently productive with ”watery-bubbly sputum”. As he was severely short of breath, he spent the night inside a cave. He descended to the clinic after no improvement of symptoms the next morning. Upon arrival, the patient was well oriented but was having labored breathing and using accessory muscles. There was fatigue without headache, nausea or dizziness. No symptoms suggestive of pneumonia or upper respiratory tract infection were present prior to decompensation. 3years ago, he suffered from HAPE at Amolapcha base (5000 m) and was treated in Lukla for a week. He had no hypertension or any other medical conditions. The COVID-19 vaccine doses were uptodate as per recommendation but previous vaccination history could not be recalled. His heart rate was 105 min-1, blood pressure was 122/86 mm Hg, respiratory rate was 32 min-1, oxygen saturation at room air was 67% and the oral temperature was 99.1 degrees Fahrenheit. There was no pedal edema, parasternal heave or hepatomegaly. Vocal fremitus was normal. Auscultation revealed inspiratory crepitations in the infra-axillary regions bilaterally. USG revealed multiple comet tail signs on the inferior axillary regions bilaterally, which were more prominent on the right side. (Figure 2) The B-lines in other segments were not as prominent. There was no consolidation. Oral Nifedipine SR 20mg three times a day was started along with O2 from an oxygen concentrator at 10L min-1 via facemask. The treatment improved SpO2 to 98% within 15 minutes. His oxygen saturation was maintained at 93% from oxygen at 3L min-1. Cough remitted and shortness of breath resolved the next morning. His saturation in room air was 91% at rest and 88% following a short walk. He was advised to descend while continuing Nifedipine for 3 days. However, his descent happened only after he somehow managed to deliver the goods up to Thukla.
Clinical Case 3 (Unilateral HAPE):
A 32 years female presented to the clinic with a cough for 8 days. The productive cough started at 2800m in Phakding and was associated with fever. Initial symptoms got resolved after 7 days of Amoxicillin. However, there was some remnant intermittent dry cough. At Lobuche (4800m) she started having persistent coughs with “watery” sputum. Persistent cough brought her to the high-altitude clinic at 4200m. She had shortness of breath during descent but no shortness of breath at rest or lying down. She had no fever, chest pain or palpitation. She had a mild generalized headache at Lobuche, which resolved following descent. Her appetite was normal; she had no nausea, vomiting or dizziness. She had been taking acetazolamide along with chlorpheniramine-bromhexine cough syrup prior to her arrival at the clinic. She had no significant medical history. Vaccination status was up-to-date. There was no history of altitude-related illness in her only altitude trip to 4200m. The patient was able to walk comfortably to the clinic. Her heart rate was 115, oxygen saturation was 77%, respiratory rate was 16 min-1, blood pressure was 126/82 and oral temperature was 98.8 degrees Fahrenheit. There were no signs of respiratory distress or pedal edema. The apex beat was palpable on the 5th intercostal space in the midclavicular line. There was no parasternal heave. Vocal fremitus was normal in all segments. Heart sounds were normal. There was equal air entry with broncho-vesicular sounds in all segments of both lungs except the right inferior regions that had late coarse inspiratory crackles, which persisted until the early expiratory phase. Chest ultrasonography revealed no pericardial or pleural collection. Lung sliding was normal bilaterally. Left-sided chest ultrasonography revealed multiple A-lines with no signs of consolidation. However, Right-sided chest ultrasonography revealed A-lines along with multiple moderately interspaced B-lines (7-8) on the inferior segment, but no signs of consolidation. The superior segments revealed A-lines with few B-lines (5-6) (Figure 3). Dexamethasone 8mg was given immediately; followed by Nifedipine SR 20 mg, three times a day and tablet Dexamethasone 4mg four times a day. The oxygen concentrator provided oxygen at 6L min-1 via a simple facemask. Within 30 minutes of treatment, her oxygen saturation improved to 93% and her heart rate to 102 min-1. Her cough was relieved 2 hours after starting the treatment. She received treatment in the clinic for 12 hours. Following overnight treatment, her cough remitted while saturation improved to 85% on room air. However, there were persistent late inspiratory crackles, albeit of lesser duration and intensity. On repeat ultrasonography, there were 2 B-lines in the left inferior chest fields. (Figure 4) There was no immediate rescue available, so she had to stay for another day at the same altitude without oxygen. She was then discharged on 2 more doses of Dexamethasone and Nifedipine 20 mg three times per day until descent and was asked to stay very close to the treatment facility. She descended the day after the discharge. Upon further contact, she stated that had no cough or difficulty breathing and had a sound sleep on the night after her discharge.