Diagnosis Of Acute Mountain Sickness Research Articles

Matrix metalloproteinase-9 and substance-P as predictors for early-stage diagnosis of acute mountain sickness

IntroductionAlthough acute mountain sickness (AMS) can be a life-threatening condition, early diagnosis is difficult due to vague and non-specific symptoms. The aim of this study is to investigate biochemical markers that can detect high-altitude diseases in advance. Eight different biomarkers (BNP, HIF-1α, NGAL, MMP-3, MMP-9, SESN2, substance P (SP), and U-II) were studied, and their relationship with AMS was investigated. MethodsOf the 84 mountaineers who participated in the mountaineering training organized by the Turkish Mountaineering Federation in the Rize Kaçkar Mountains in 2018, 52 volunteered to participate in the study. Twelve hours after the participants reached an altitude of 2200 m (exposed to moderate hypoxia), their vital parameters were measured, and blood samples were taken for biochemistry tests. Vital signs and Lake Louise (LL) AMS scores were recorded every 24 h during the following 72 h. The participants were divided into two groups according to their LL scores: those with AMS and those without (AMS+ and AMS −), and the vital parameters and biomarker levels of both groups were compared and evaluated. ResultsOf the volunteers participating in the study, 35 (67.3%) were male and 17 (32.7%) were female, although there was no gender difference in terms of susceptibility to AMS. Among the investigated markers in the AMS + group, MMP-9 and SP were statistically significantly higher (p = 0.037 and p = 0.038, respectively). There were no statistical differences between AMS− and AMS+ groups with regard to heart rate, oxygen saturation, and systolic and diastolic blood pressure values (p = 0.507, p = 0.929, p = 0.955, p = 0.572, respectively). ConclusionThere were significant differences between the AMS− and AMS+ groups in terms of MMP-9 and SP. However, differences in physical indexes between the groups were not statistically significant. This could provide objective indexes for scanning and screening individuals susceptible to AMS in the early stages of rapid ascending.

Evaluation of the Lake Louise Score for Acute Mountain Sickness and Its 2018 Version in a Cohort of 484 Trekkers at High Altitude.

Richalet, Jean-Paul, Chantal Julia, and François J. Lhuissier. Evaluation of the Lake Louise Score for acute mountain sickness and its 2018 version in a cohort of 484 trekkers at high altitude. High Alt Med Biol. 22:353-361, 2021. Background: The Lake Louise Score (LLS) is widely used in field studies and chamber studies for the diagnosis of Acute Mountain Sickness (AMS). This score aggregates symptoms that are nonspecific: headache, gastrointestinal symptoms, fatigue, dizziness and sleep disturbance can be due to a variety of causes unrelated to altitude hypoxia. The objectives of this study were to (1) reevaluate the need for a headache score >0 for the diagnosis of AMS, (2) evaluate the role of sleep disturbances, in relation with other symptoms, (3) evaluate the significance of dizziness. Materials and Methods: We analyzed LLS from 484 trekkers at high altitude. Among them, 212 suffered from moderate AMS (mAMS: 3 ≤ LLS < 6) and 115 from severe AMS (sAMS: LLS ≥ 6). Results: Cluster analysis of AMS revealed three main groups presenting the following symptoms: Group 1 includes 254 subjects who had less than 2 symptoms; Group 2 includes 137 subjects who had fatigue, sleep disturbance, and headache, corresponding to mAMS; Group 3 includes 93 subjects who had headache, fatigue, dizziness and sleep disturbance, corresponding to sAMS. A headache score of zero was found in 25% of mAMS and 5% of sAMS subjects. Only the absence of headache associated with the absence of fatigue was specific of absence of sAMS. In subjects with a dizziness score > 1, end-tidal partial pressure of carbon dioxide during a hypoxic exercise test was lower than that in subjects with a dizziness score < 2. Subjects with high ventilatory response to hypoxia may develop dizziness with high altitude exposure. Conclusion: (1) An isolated headache score > 0 should not be mandatory to define AMS, (2) sleep disruption contributes to the diagnosis of AMS, (3) gastrointestinal symptoms and dizziness are weaker contributors to the LLS, (4) dizziness might be linked to a hyperresponsiveness to hypoxia and not to AMS itself.

P4370Doppler echocardiography, RV Strain and 3D RV Imaging in diagnosis of Acute mountain sickness

Abstract Introduction Right Ventricular (RV) strain and 3D RV ejection fraction sensitivity and specificity has made it a practical and reliable test to detect Acute mountain sickness. All previous studies have been done mainly using M Mode and 2D Echo. Hence it was conceived that 3D Echocardiography would be a better option. Regardless of the type of Acute Mountain Sickness (AMS), the echocardiographic evidence is always the same: Severe Pulmonary hypertension. The visual analysis of these abnormalities requires a trained operator. This operator-dependence has promoted the search for a semiautomatic method to reduce limitations of Echocardiography and improve test accuracy Purpose The purpose was to study AMS by 3D Echocardiography Methods and results Two dimensional echocardiography with RV strain analysis by speckle tracking echocardiography along with 3D RV ejection fraction was done in nine patients with AMS who were tourists on unplanned, unacclimatized assent to Pangong lake, situated near Leh-Ladakh in the Himalayas, approximately at the height of 4350 meters above sea level and six highlanders, living in Leh-Ladakh. Figure 1A shows the map of the Pangong Lake, B. Shows features of Acute Pulmonary Edema in the Chest X-ray from a patient with AMS, C. Shows the TAPSE (Tricuspid Annular Plane Systolic Excursion) D. Shows the Speckle tracking derived RV Free Wall strain (From a software made for LV) and E: Methodology to derive 3D RV Ejection Fraction. 3D Echocardiographic Equipment with LV strain (which was modified to derive RV Free wall strain) and 3D RV Ejection Fraction software was used for acquisition of images and offline analysis was done. TAPSE, FAC, RV Free wall strain and 3D RV EF were consistently lower in patients with AMS than in persons living in high altitude (High landers). TR peak gradient, RV EDV index, RV ESV index were elevated in AMS patients compared to High landers. Table 1. Table 1 Age Sex M/F 3D RV EF% TAPSE (mm) FAC TRP E/e' RVFW Strain RV EDVI (ml/m2) RV ESVI (ml/m2) AMS (9) 40.2±2.3 5/4 36±3.2 16±1.7 38.2±2.7 49.2±7.6 5.4±1.2 14±1.9 55±3.7 35±2.4 High Landers (6) 53.6±3.7 5/1 45±2.3 20±2.7 46.9±4.7 26.52±6.7 7±1.7 28±2.2 52±4.1 29±2.8 RV: Right Ventricle; EF: Ejection Fraction; TAPSE: Tricuspid Annular Plane Systolic Excursion; FAC: Fractional Area Change; TRP: Tricuspid Regurgitation Peak gradient; E: Mitral E Velocity; e' Medial mitral Tissue doppler e velocity; FW: Free Wall; EDVI: End Diastolic Volume Index; ESV: End systolic volume index. Figure 1 Conclusion Strain or myocardial deformation analysis based on two-dimensional (2D) speckle tracking and 3D RV ejection fraction is feasible even in the remote altitudes apart from standard M Mode and Doppler measurements and allow accurate quantification in analysis of acute mountain sickness.

P616RV Strain and 3D RV imaging in diagnosis of acute mountain sickness

Abstract Introduction Right Ventricular (RV) strain and 3D RV ejection fraction sensitivity and specificity has made it a practical and reliable test to detect Acute mountain sickness. All previous studies have been done mainly using M Mode and 2D Echo. Hence it was conceived that 3D Echocardiography would be a better option. Regardless of the type of Acute Mountain Sickness (AMS), the echocardiographic evidence is always the same: Severe Pulmonary hypertension. The visual analysis of these abnormalities requires a trained operator. This operator-dependence has promoted the search for a semiautomatic method to reduce limitations of Echocardiography and improve test accuracy Purpose The purpose was to study AMS by 3D Echocardiography Methods and results Two dimensional echocardiography with RV strain analysis by speckle tracking echocardiography along with 3D RV ejection fraction was done in nine patients with AMS who were tourists on unplanned, unacclimatized assent to Pangong lake, situated near Leh-Ladakh in the Himalayas, approximately at the height of 4350 meters above sea level and six highlanders, living in Leh-Ladakh. Figure 1A shows the map of the Pangong Lake, B. Shows features of Acute Pulmonary Edema in the Chest X-ray from a patient with AMS, C. Shows the TAPSE (Tricuspid Annular Plane Systolic Excursion) D. Shows the Speckle tracking derived RV Free Wall strain (From a software made for LV) and E: Methodology to derive 3D RV Ejection Fraction. 3D Echocardiographic Equipment with LV strain (which was modified to derive RV Free wall strain) and 3D RV Ejection Fraction software was used for acquisition of images and offline analysis was done. TAPSE, FAC, RV Free wall strain, RV EDV index, RV ESV index and 3D RV EF were consistently lower in patients with AMS than in persons living in high altitude (High landers) Table 1 Results Age Sex M/F Diabetes/ Hypertension TAPSE (mm) FAC RVFW Strain % RV EDVI (ml/m2) RV ESVI (ml/m2) 3D RV EF % AMS (9) 40.2±2.3 5/4 1/2 16±1.7 38.2±2.7 14±1.9 55±3.7 35±2.4 36±3.2 High-Landers (6) 53.6±3.7 5/1 1/1 20±2.7 46.9±4.7 28±2.2 52±4.1 29±2.8 45±2.3 Fig 1 Conclusion Strain or myocardial deformation analysis based on two-dimensional (2D) speckle tracking and 3D RV ejection fraction is feasible even in the remote altitudes and allow accurate quantification which has resulted in a growing interest to introduce this new technique in analysis of acute mountain sickness.

The Smell of Hypoxia: using an electronic nose at altitude and proof of concept of its role in the prediction and diagnosis of acute mountain sickness.

† Electronic nose (e‐nose) devices may be used to identify volatile organic compounds (VOCs) in exhaled breath. VOCs generated via metabolic processes are candidate biomarkers of (patho)physiological pathways. We explored the feasibility of using an e‐nose to generate human “breathprints” at high altitude. Furthermore, we explored the hypothesis that pathophysiological processes involved in the development of acute mountain sickness (AMS) would manifest as altered VOC profiles. Breath analysis was performed on Sherpa and lowlander trekkers at high altitude (3500 m). The Lake Louise Scoring (LLS) system was used to diagnose AMS. Raw data were reduced by principal component (PC) analysis (PCA). Cross validated linear discriminant analysis (CV‐LDA) and receiver‐operating characteristic area under curve (ROC‐AUC) assessed discriminative function. Breathprints suitable for analysis were obtained from 58% (37/64) of samples. PCA showed significant differences between breathprints from participants with, and without, AMS; CV‐LDA showed correct classification of 83.8%, ROC‐AUC 0.86; PC 1 correlated with AMS severity. There were significant differences between breathprints of participants who remained AMS negative and those whom later developed AMS (CV‐LDA 68.8%, ROC‐AUC 0.76). PCA demonstrated discrimination between Sherpas and lowlanders (CV‐LDA 89.2%, ROC‐AUC 0.936). This study demonstrated the feasibility of breath analysis for VOCs using an e‐nose at high altitude. Furthermore, it provided proof‐of‐concept data supporting e‐nose utility as an objective tool in the prediction and diagnosis of AMS. E‐nose technology may have substantial utility both in altitude medicine and under other circumstances where (mal)adaptation to hypoxia may be important (e.g., critically ill patients).

Exploration of Acute Phase Proteins and Inflammatory Cytokines in Early Stage Diagnosis of Acute Mountain Sickness.

Early diagnosis of acute mountain sickness (AMS) is currently based on personal appreciation of the severity of symptoms. A more objective method to diagnose AMS is required. Inflammatory cytokines and acute phase proteins have been reported to be different at high altitude. A total of 104 male soldiers rapidly ascending from Beijing (20-60 m) to Germu, Qinghai (3200 m), were divided into AMS group and non-AMS group according to the Lake Louis Score system. Blood pressure, pulse rate, and oxygen saturation were measured. Forty-nine blood samples were collected before and on the 3rd day after ascending to the high altitude. Serum haptoglobin (Hp), transferrin (Tf), and complement C3 were detected by immune scattered nephelometry, whereas serum interleukin-1beta (IL-1β), IL-6, and tumor necrosis factor-α (TNF-α) were detected by chemical luminescence immunity analyzer. The sensitivity, specificity, and receiver operating characteristic curve were evaluated. Youden index with the maximum value was used to determine cutoff values of each parameter. Logistic regression was performed to determine the diagnostic efficiency of combination of three cytokines. Differences of physical indexes between AMS group and non-AMS group were of no statistical significance. In AMS group, serum Tf significantly increased while Hp decreased when compared with non-AMS group. Serum IL-1β, IL-6, and TNF-α were higher in the AMS group than in the non-AMS group. The cutoff values for Tf, Hp, IL-1β, IL-6, and TNF-α were 263.5 mg/dL, 119.35 mg/dL, 6.2 pg/mL, 15.05 pg/mL, and 18.35 pg/mL, respectively. Area under the curve (AUC) of combining three cytokines together was higher than AUC of each cytokine separately. Acute phase proteins and inflammatory cytokines (IL-1β, IL-6, and TNF-α) show significant changes between the AMS group and the non-AMS group. Combination of inflammatory cytokines or acute phase proteins improves the specificity for diagnosis of AMS. This might provide objective indexes for scanning and screening individuals susceptible to AMS in the early stage of rapid ascending.

Objective Versus Self-Reported Sleep Quality at High Altitude.

Anderson, Paul J., Christina M. Wood-Wentz, Kent R. Bailey, and Bruce D. Johnson. Objective versus self-reported sleep quality at high altitude. High Alt Med Biol. 24:144-148, 2023. Background: Previous studies have found little relationship between polysomnography and a diagnosis of acute mountain sickness (AMS) using the Lake Louise Symptom Questionnaire (LLSQ). The correlation between sleep question responses on the LLSQ and polysomnography results has not been explored. We compared LLSQ sleep responses and polysomnography data from our previous study of workers rapidly transported to the South Pole. Methods: Sixty-three subjects completed a 3-hour flight from sea level to the South Pole (3200 m, 9800 ft). Participants completed limited overnight polysomnography on their first night and completed LLSQ upon awakening. We compared polysomnography results at the South Pole with sleep question responses on the LLSQ to assess their degree of correspondence. Results: Twenty-two (30%) individuals reported no sleep problems whereas 20 (32%) reported some problems and 20 (33%) individuals reported poor sleep and 1 reported no sleep (n = 1). Median sleep efficiency was (94%) among response groups and mean overnight oxygen saturation was 81%. Median apnea hypopnea index (AHI; events/hour) was 10.2 in those who reported no problems sleeping, 5.1 in those reporting some problems sleeping, and 13.7 in those who reported poor sleep. These differences were not statistically significant. Conclusion: Self-reported sleep quality varied but there were no associated significant differences in sleep efficiency, overnight oxygen saturation, nor AHI. Studies that explore the role of objective sleep quality in the development of AMS should remove the sleep question on the LLSQ from AMS scoring algorithms.

Differences Between the "Chinese AMS Score" and the Lake Louise Score in the Diagnosis of Acute Mountain Sickness.

The Chinese AMS score (CAS) is used in clinical medicine and research to diagnosis acute mountain sickness (AMS). However, the Lake Louise Score (LLS) is the well-accepted standard for diagnosing AMS. The difference between the CAS and LLS questionnaires is that the CAS considers more nonspecific symptoms. The aim of the present study was to evaluate differences in AMS prevalence according to the LLS and CAS criteria. We surveyed 58 males who traveled from Chongqing (300 m) to Lhasa (3658 m) via the Qinghai-Tibet train. Cases of AMS were diagnosed using LLS and CAS questionnaires in a few railway stations at different evaluation areas along the road. We subsequently evaluated discrepancies in values related to the prevalence of AMS determined using the 2 types of questionnaires (CAS and LLS). The prevalence of CAS-diagnosed AMS indicated that the percentage of AMS cases among the 58 young men was 29.3% in Golmud, 60.3% in Tanggula, 63.8% in Lhasa, 22.4% on the first day after arrival in Lhasa, 27.6% on the second day, 24.1% on the third day, and 12.1% on the fourth day. The prevalence of LLS-diagnosed AMS in Golmud was 10.3%, 38% in Lhasa, and 6.9% on day 1, the prevalence in each station was lower than that as assessed by the CAS. Our experimental data indicate that AMS diagnoses ascertained using the CAS indicate a higher AMS prevalence than those ascertained using the LLS. Through statistical analysis, the CAS seems capable of effectively diagnosing AMS as validated by LLS (sensitivity 61.8%, specificity 92.7%).

Optic Nerve Sheath Diameter Increase on Ascent to High Altitude: Correlation With Acute Mountain Sickness.

Elevated optic nerve sheath diameter on sonography is known to correlate with increased intracranial pressure and is observed in acute mountain sickness. This study aimed to determine whether optic nerve sheath diameter changes on ascent to high altitude are associated with acute mountain sickness incidence. Eighty-six healthy adults enrolled at 1240 m (4100 ft), drove to 3545 m (11,700 ft) and then hiked to and slept at 3810 m (12,500 ft). Lake Louise Questionnaire scores and optic nerve sheath diameter measurements were taken before, the evening of, and the morning after ascent. The incidence of acute mountain sickness was 55.8%, with a mean Lake Louise Questionnaire score ± SD of 3.81 ± 2.5. The mean maximum optic nerve sheath diameter increased on ascent from 5.58 ± 0.79 to 6.13 ± 0.73 mm, a difference of 0.91 ± 0.55 mm (P = .09). Optic nerve sheath diameter increased at high altitude regardless of acute mountain sickness diagnosis; however, compared to baseline values, we observed a significant increase in diameter only in those with a diagnosis of acute mountain sickness (0.57 ± 0.77 versus 0.21 ± 0.76 mm; P = .04). This change from baseline, or Δ optic nerve sheath diameter, was associated with twice the odds of developing acute mountain sickness (95% confidence interval, 1.08-3.93). The mean optic nerve sheath diameter increased on ascent to high altitude compared to baseline values, but not to a statistically significant degree. The magnitude of the observed Δ optic nerve sheath diameter was positively associated with acute mountain sickness diagnosis. No such significant association was found between acute mountain sickness and diameter elevation above standard cutoff values, limiting the utility of sonography as a diagnostic tool.

GW24-e0522 Incidence of acute mountain sickness in young adults at 3200 meters-comparison of the Lake Louise scoring and Chinese scoring systems

ObjectivesThe purpose of this study was to compare two scoring systems used for diagnosis of acute mountain sickness (AMS): Lake Louise Scoring (AMS-LLS) and Chinese Scoring System (AMS-CSS).Methods339 healthy young...

Anxiety correlates with somatic symptoms and sleep status at high altitudes

High altitude exposure results in many physical and psychological discomforts, with anxiety and sleep disturbances being the most common ones. This cross-sectional study was performed to explore the relationship between anxiety, somatic symptoms, and sleep status at high altitude. A sample of 426 young males between 18 and 24years old ascended from low-level land to 3600m, where they acclimated for 40days, before ascending to 4400m. Questionnaires including the Louise Lake Score (LLS, for diagnosis of acute mountain sickness [AMS]), the Self-rating Anxiety Scale (SAS), the Epworth Sleepiness Scale (ESS), and the Athens Insomnia Scale (AIS) were administered immediately before departure from 3600m (40th day) and the day after arrival at 4400m (20days after the first data collection). Physiological parameters were also measured. We observed that 49 of 426 and 51 of 329 people were diagnosed with anxiety according to SAS at 3600 and 4400m, respectively. Physical symptoms were more severe in subjects with anxiety, and the severity of anxiety was significantly positively correlated to the severity of insomnia and increased heart rate (HR). Overall, these data indicate that after 40days acclimatization in 3600m, anxious persons have more severe somatic symptoms. When ascending to higher altitudes, these individuals are more likely to develop AMS, show more severe symptoms, and are prone to insomnia and more serious daytime sleepiness. Insomnia and elevated HR are indicators of anxiety severity.

Incidence of acute mountain sickness in young adults at 3200 meters: comparison of the Lake Louise Scoring and Chinese Scoring Systems

The purpose of this study was to compare two scoring systems used for the diagnosis of acute mountain sickness (AMS): the Lake Louise Scoring (AMS-LLS) and the Chinese Scoring Systems (AMS-CSS). In total, 339 healthy young adult volunteers residing at sea level ascended to 3200 m by train and bus over a total journey time of 48 h. All subjects ascended in the same manner and were divided into three groups that were assessed after one (N = 88), two (N = 91), and three (N = 160) nights, respectively, at altitude. The overall incidence of AMS was 17.11% (N = 58) and 29.79% (N = 101) according to the AMS-LLS and AMS-CSS, respectively. Two participants (0.59%) experienced high-altitude pulmonary edema. Both scoring systems showed the highest incidence of AMS after the second night at high altitude. The AMS-CSS and AMS-LLS scores were significantly correlated (Pearson's r = 0.820, P < 0.001). The AMS-CSS identified all AMS subjects diagnosed by the AMS-LLS, and an additional 43 subjects. The dominant symptoms were reduced exercise tolerance (61.7%), fatigue (49.0%), dizziness (28.9%), chest distress (28.3%), and headache (27.4%). Compared with the AMS-LLS, the sensitivity, specificity, and positive and negative predictive values of the AMS-CSS were 100, 84.7, 57.43, and 100%, respectively. There was no relationship between oxygen saturation levels and AMS scores at 3200 m. In summary, the AMS-CSS was similar to AMS-LLS, except that it resulted in more positive diagnoses, and headache did not play a large diagnostic role.

Evaluation of the Balance Error Scoring System (BESS) in the Diagnosis of Acute Mountain Sickness at 4380 m

Ascent to altitude is associated with a decrease in balance; however, the effect of acute mountain sickness (AMS) status on balance is variable depending on the test used and the altitude at which the test is performed. Here, we report preliminary findings on the relationship between the balance error scoring system (BESS) and AMS at the 2010 Janai Purnima festival at Gosainkunda, Nepal (4380 m). All subjects (n=37) completed a shortened BESS test (mBESS) while a subset completed the full BESS test (n=27). Pulse oximetry was used to measure heart rate and oxygen saturation, and blood pressure was measured by sphygmomanometer. Balance test scores (BESS and mBESS) and physiological measurements were compared between groups with AMS (AMS⁺) and without AMS (AMS⁻). Receiver-operator characteristic (ROC) curves were used to compare the abilities of the BESS and mBESS tests to correctly identify the AMS status of subjects. The AMS⁺ group had significantly higher Lake Louise scores than the AMS⁻ group (mean=4.0 (standard deviation=1.3) vs. 0.3 (0.6), p<0.001). The AMS⁺ group also scored significantly higher on both the mBESS (6.6 (3.5) vs. 2.7 (1.7) errors, p=0.018) and the BESS tests (19.2 (8.8) vs. 10.4 (6.0) errors, p=0.001) compared to the AMS⁻ group, indicating inferior balance in the AMS⁺ group. The area under the ROC curve was significantly greater for the BESS test (0.895) compared to the mBESS test (0.690, p=0.02), implying that the full BESS test more accurately identified a subject's AMS status. Additional studies are needed to determine if BESS could be a useful adjunct to the clinical diagnosis of AMS.

Background Rates of Acute Mountain Sickness-Like Symptoms at Low Altitude in Adolescents Using Lake Louise Score

To record the incidence of symptoms consistent with a diagnosis of acute mountain sickness (AMS), using the Lake Louise questionnaire, in adolescents hiking at low altitude. The study was carried out on a cohort of 123 adolescents during a 3-day trip on Dartmoor, UK, at an altitude of less than 500 m. The incidence of symptoms experienced was measured using the Lake Louise questionnaire, which was completed twice daily by each participant. An episode consistent with AMS, but in the low altitude setting, was defined as a score of 3 or more on the Lake Louise questionnaire in the presence of a headache. There were 59 boys and 64 girls in the study with an average age of 16.7 years. The response rate was 100%. A total of 59 episodes of scores consistent with AMS was recorded during the 3-day period. Forty-two of these episodes were reported by girls (71%). AMS scores between 3 and 8 were recorded, and the daily incidence rates of scores consistent with AMS but at low altitude were between 7.3% and 11.3%. This study shows that adolescents at low altitude reported a background incidence of symptoms that at high altitude would lead to a diagnosis of AMS.

Pro: Headache Should Be a Required Symptom for the Diagnosis of Acute Mountain Sickness

The diagnosis of acute mountain sickness (AMS) continues to pose problems to altitude sojourners, physicians, and researchers because of its subjective nature relying essentially on a subject’s appreciation of the presence and severity of symptoms (Roach and Kayser, 2007). Even though AMS is characterized by an ensemble of symptoms (Hackett and Roach, 2001), headache has been recognized as its key symptom at least since Ravenhill’s description in 1911 (Ravenhill, 1913). He described the experiences of ‘‘a majority of newcomers . . . . wake up the next morning with a severe frontal headache . . . . . any attempt at exertion increases the headache, which is nearly always confined to the frontal region.’’ This central role of headache was codified in the current version of the Lake Louise Questionnaire (Roach et al., 1993) that states that a ‘‘diagnosis of AMS is based on a recent gain in altitude, at least several hours at the new altitude, and the presence of headache and at least one of the following symptoms: gastrointestinal upset (anorexia, nausea or vomiting), fatigue or weakness, dizziness or lightheadedness and difficulty sleeping.’’ All surveys of AMS identify headache as the predominant and most prevalent symptom. Singh et al. (1969) noted from a survey of 1925 soldiers rapidly transported to high altitude that ‘‘Headache was not only the commonest but also the most persistent symptom.’’ In a study of 146 trekkers with AMS, Hackett et al. observed the following predominance of headache compared to other symptoms: headache (96%), insomnia (70%), anorexia (38%), nausea (35%), dizziness (27%), excessive breathlessness on exertion or at rest (25%), headache unrelieved by analgesics (26%), reduced urine (19%), marked lassitude (13%), vomiting (14%), incoordination (11%) (Hackett et al 1976). And finally, in a large survey at moderate altitudes, Honigman et al. confirmed the importance of headache in AMS with 62% of 3158 conference attendees reporting moderate to severe headache, and the next most common complaint being sleep disturbance at 31%, and anorexia at 11% and vomiting at only 3% (Honigman et al., 1993). Thus it seems clear that for AMS the cardinal symptom is headache in all studies, in all populations, and at a wide range of altitudes. Our position is that from a research perspective there are important advantages to defining AMS as a collection of symptoms that includes, always, a headache. The same is obviously not true for clinical management of altitude illness. This contrast between the needs for research versus best practice in clinical care forms the basis of our stance. In spite of several decades of sustained research efforts, the basic pathophysiology of AMS still remains elusive. We believe that a focus on high altitude headache will help unravel the puzzle of the pathophysiology of AMS. By stipulating for research purposes that headache be included in the definition of AMS, scientists seek to increase signal-to-noise ratio in AMS subjective symptom reporting. Unfortunately, subjective perception and reporting of symptoms is currently the only way to diagnose and quantify AMS. An example of excess noise is that without obligatory headache, a research subject who had a very bad night sleep and is dizzy at the time of completing the questionnaire could have a ‘‘severe’’ AMS score. Yet we know from several studies that poor sleep at altitude is not necessarily related directly to AMS. And dizziness can be secondary to hypoxemia, or to hypohydration, a common, non-AMS-related phenomenon at high altitude. Similarly, nausea and vomiting can be associated with the onset of AMS, or secondary to a bad headache of any cause, especially migraine, and in the field can also be secondary to gastrointestinal infection. Thus, obligatory presence of headache in the research scoring of AMS symptoms serves an important role by increasing the likelihood that the central symptom of AMS, first reported so clearly by Ravenhill, remains the focus of research studies. It should be noted that

Con: Headache Should not Be a Required Symptom for the Diagnosis of Acute Mountain Sickness

High Altitude Medicine & BiologyVol. 12, No. 1 PRO and CON edited by Erik R. SwensonCon: Headache Should not Be a Required Symptom for the Diagnosis of Acute Mountain SicknessJohn B. WestJohn B. WestSearch for more papers by this authorPublished Online:31 Mar 2011https://doi.org/10.1089/ham.2010.1068AboutSectionsView articleView Full TextPDF/EPUB ToolsPermissionsDownload CitationsTrack CitationsAdd to favorites Back To Publication ShareShare onFacebookTwitterLinked InRedditEmail View articleFiguresReferencesRelatedDetailsCited ByEvaluation of the Lake Louise Score for Acute Mountain Sickness and Its 2018 Version in a Cohort of 484 Trekkers at High Altitude Jean-Paul Richalet, Chantal Julia, and François J. Lhuissier13 December 2021 | High Altitude Medicine & Biology, Vol. 22, No. 4Akute HöhenkrankheitCharacteristics of Headache and Relationship to Acute Mountain Sickness at 4559 Meters Michael Schneider and Peter Bärtsch21 December 2018 | High Altitude Medicine & Biology, Vol. 19, No. 4The influence of hypoxia and prolonged exercise on attentional performance at high and extreme altitudes: A pilot study3 October 2018 | PLOS ONE, Vol. 13, No. 10Isolated psychosis during exposure to very high and extreme altitude – characterisation of a new medical entity5 December 2017 | Psychological Medicine, Vol. 48, No. 11Exploration of Acute Phase Proteins and Inflammatory Cytokines in Early Stage Diagnosis of Acute Mountain Sickness Chi Wang, Hui Jiang, Jinyan Duan, Jingwen Chen, Qi Wang, Xiaoting Liu, and Chengbin Wang1 June 2018 | High Altitude Medicine & Biology, Vol. 19, No. 2The 2018 Lake Louise Acute Mountain Sickness Score Robert C. Roach, Peter H. Hackett, Oswald Oelz, Peter Bärtsch, Andrew M. Luks, Martin J. MacInnis, J. Kenneth Baillie, , Eric Achatz, Edi Albert, Jon S. Andrews, James D. Anholm, Mohammad Zahid Ashraf, Paul Auerbach, Buddha Basnyat, Beth A. Beidleman, R.R. Berendsen, Marc Moritz Berger, Konrad E. Bloch, Hermann Brugger, Annalisa Cogo, Ricardo Gonzalez Costa, Andrew Cumpstey, Allen Cymerman, Tadej Debevec, Catriona Duncan, David Dubowitz, Angela Fago, Michael Furian, Matt Gaidica, Prosenjit Ganguli, Michael P.W. Grocott, Debra Hammer, David Hall, David Hillebrandt, Matthias Peter Hilty, Gigugu Himashree, Benjamin Honigman, Ned Gilbert-Kawai, Bengt Kayser, Linda Keyes, Michael Koehle, Samantha Kohli, Arlena Kuenzel, Benjamin D. Levine, Mona Lichtblau, Jamie Macdonald, Monika Brodmann Maeder, Marco Maggiorini, Daniel Martin, Shigeru Masuyama, John McCall, Scott McIntosh, Gregoire Millet, Fernando Moraga, Craig Mounsey, Stephen R. Muza, Samuel Oliver, Qadar Pasha, Ryan Paterson, Lara Phillips, Aurélien Pichon, Philipp A. Pickerodt, Matiram Pun, Manjari Rain, Drummond Rennie, Ge Ri-Li, Steven Roy, Samuel Verges, Tatiana Batalha Cunha dos Santos, Robert B. Schoene, Otto D. Schoch, Surinderpal Singh, Talant Sooronbaev, Craig D. Steinback, Mike Stembridge, Glenn Stewart, Tsering Stobdan, Giacomo Strapazzon, Andrew W. Subudhi, Erik Swenson, A. A. Roger Thompson, Martha Tissot van Patot, Rosie Twomey, Silvia Ulrich, Nicolas Voituron, Dale R. Wagner, Shih-hao Wang, John B. West, Matt Wilkes, Gabriel Willmann, Michael Yaron, and Ken Zafren1 March 2018 | High Altitude Medicine & Biology, Vol. 19, No. 1Wearable physiological sensors and real-time algorithms for detection of acute mountain sicknessJournal of Applied Physiology, Vol. 124, No. 3Does This Patient Have Acute Mountain Sickness?JAMA, Vol. 318, No. 18Physiological and psychological factors associated with onset of high-altitude headache in Chinese men upon acute high-altitude exposure at 3700 m5 May 2016 | Cephalalgia, Vol. 37, No. 4Acute high-altitude sickness31 January 2017 | European Respiratory Review, Vol. 26, No. 143Subjective assessment of acute mountain sickness: investigating the relationship between the Lake Louise Self-Report, a visual analogue scale and psychological well-being scales22 September 2016 | SpringerPlus, Vol. 5, No. 1Drug Use and Misuse in the Mountains: A UIAA MedCom Consensus Guide for Medical Professionals Enrico Donegani, Peter Paal, Thomas Küpper, Urs Hefti, Buddha Basnyat, Anna Carceller, Pierre Bouzat, Rianne van der Spek, and David Hillebrandt1 September 2016 | High Altitude Medicine & Biology, Vol. 17, No. 3Acute Mountain Sickness Symptoms Depend on Normobaric versus Hypobaric HypoxiaBioMed Research International, Vol. 2016High AltitudeAkute Höhenkrankheit (AMS)20 May 2015Network Analysis Reveals Distinct Clinical Syndromes Underlying Acute Mountain Sickness22 January 2014 | PLoS ONE, Vol. 9, No. 1Acute Mountain Sickness and High Altitude Cerebral Oedema9 November 2013Altitude Sickness in Climbers and Efficacy of NSAIDs Trial (ASCENT): Randomized, Controlled Trial of Ibuprofen Versus Placebo for Prevention of Altitude IllnessWilderness & Environmental Medicine, Vol. 23, No. 4Does Ibuprofen Prevent Acute Mountain Sickness?Wilderness & Environmental Medicine, Vol. 23, No. 4Acute Mountain Sickness without Headache at Low Altitude1 November 2012 | JRSM Short Reports, Vol. 3, No. 11Short-term intermittent hypoxia reduces the severity of acute mountain sickness1 August 2012 | Scandinavian Journal of Medicine & Science in Sports, Vol. 22, No. 5 Volume 12Issue 1Apr 2011 InformationCopyright 2011, Mary Ann Liebert, Inc.To cite this article:John B. West.Con: Headache Should not Be a Required Symptom for the Diagnosis of Acute Mountain Sickness.High Altitude Medicine & Biology.Apr 2011.23-25.http://doi.org/10.1089/ham.2010.1068Published in Volume: 12 Issue 1: March 31, 2011PDF download

Pulse Oximetry in the Diagnosis of Acute Mountain Sickness

Acute mountain sickness (AMS) is a common condition in individuals who travel to altitudes over 2000 m. While AMS is an important public health problem, no measurements can reliably support or predict the diagnosis with any degree of confidence. We therefore set out to study whether pulse oximetry data are associated with AMS. We studied 169 subjects who had recently arrived by foot at 3080 m. Subjects completed a demographic survey, which collected data on ascent profiles and AMS symptoms. Resting arterial oxygen saturation and pulse rate were then measured using finger pulse oximetry. Forty-six subjects (27%) had AMS, using the Lake Louise score. Only pulse rate was significantly associated with the presence of AMS (OR: 1.4; 95% CI, 1.1 to 1.9; p < 0.05, backwards stepwise logistical regression). A trend showed worse AMS diagnoses were associated with higher mean pulse rates (p < 0.05, ANOVA linear weighted analysis). While some previous studies have shown an association between decreased oxygen saturation and acute mountain sickness at altitude, our results did not demonstrate such an association. The utility of pulse oximetry remains limited in the diagnosis of AMS. We recommend further study to determine the possible utility of pulse rate in the diagnosis and prediction of AMS.

Pulse Oximetry in the Diagnosis of Acute Mountain Sickness

Pulse Oximetry in the Diagnosis of Acute Mountain Sickness

Hysterical Conversion Disorder in a Young Girl at Moderate Altitude

Case report A 10-year-old girl hiked with other members of her group to a summit at a height of 2400 m in Switzerland. They left in the morning from their residence altitude of 600 m, were dropped off with a 4-wheel-drive car at a shelter at 1400 m, and started to hike from this point. During the ascent and after 2 hours of walking, the young girl complained of a headache and a sensation of oppression, but she reached the top together with the rest of the group. The group spent 1 hour having lunch on the summit. After lunch, her headache and her sensation of being unable to take a deep breath were exacerbated, and she became ataxic and unable to stand up; yet she did not lose consciousness. She was carried by several adults and brought down to a shelter at 1400 m after a lapse of 3 hours without improvement of her symptoms. The accompanying adults were in a hurry, and a call for help was sent out. The medical team arrived within 20 minutes by helicopter due to the inaccessibility of the shelter. The helicopter’s physician noticed that the patient was conscious, with no sensory or motor deficiency; the pupils and osteotendinous reflexes were normal. She presented dyskinetic movement of both arms and slight dysarthria, and she spoke in a hushed voice; she was completely unable to stand up (falling backward with exaggerated movements) and also had a tendency to somnolence. Arterial pressure, heart rate, respiratory rate, temperature, and oxygen saturation were all normal, yet her intense headache and her sensation of being unable to get enough air were persistent symptoms. Quite strikingly, she appeared to be completely indifferent and did not ask for any explanations about her clinical condition. She did not report any medical history. At the shelter, oxygen was administered, and an intravenous line was inserted. She was thereafter transported to the