Home About us Editorial board Search Ahead of print Current issue Archives Submit article Instructions Subscribe Contacts Login 
  • Users Online:416
  • Home
  • Print this page
  • Email this page

 Table of Contents  
Year : 2021  |  Volume : 35  |  Issue : 3  |  Page : 235-239

Effect of high altitude on the incidence of postdural puncture headache in young males: A 5-year restrospective study

1 Department of Anesthesiology and Critical Care, Army Hospital (Research and Referral), New Delhi, India
2 Department of Surgery, Military Hospital Kargil, Srinagar, Jammu and Kashmir, India

Date of Submission18-Apr-2021
Date of Decision16-Aug-2021
Date of Acceptance24-Aug-2021
Date of Web Publication29-Dec-2021

Correspondence Address:
Dr. Indranill Sikdar
Department of Anesthesiology and Critical Care, Army Hospital (Research and Referral), New Delhi
Login to access the Email id

Source of Support: None, Conflict of Interest: None

DOI: 10.4103/ijpn.ijpn_36_21

Rights and Permissions

Background: Postdural puncture headache (PDPH) is a serious and debilitating complication and a major cause of postoperative morbidity occurring after spinal anesthesia (SA) or inadvertent dural puncture after epidural anesthesia. The understanding of pathophysiology of PDPH has improved over the last few decades and its occurrence is now on decrease with use of better techniques and smaller gauge needles. Over the past several years, many of the risk factors attributable to PDPH have been identified and studied extensively, but only few studies have evaluated the effect of increasing altitude on the occurrence of PDPH. As a significant proportion of population undergo surgery in such elevations, we retrospectively evaluated the effect of high altitude on the incidence of PDPH following SA. Materials and Methods: This study was conducted at a single center, retrospective observational study in the high altitude and cold climate region, for a period of 5 years. The data collected were evaluated for the occurrence of PDPH. Results: The total number of cases undergoing surgery under SA in our center was 440 over a period of 5 years. The cumulative incidence of PDPH in this cohort was 6.6%. The incidence was 7.15% and 5.56% with use of 26G and 27G Quincke needle, respectively, which is higher than that observed in the low-lying areas. Conclusions: The incidence of PDPH is higher in patients undergoing surgery under SA at high altitude.

Keywords: Cerebrospinal fluid leak, high altitude, postdural puncture headache, spinal anesthesia

How to cite this article:
Parikh B, Pande T, Dua A, Sikdar I. Effect of high altitude on the incidence of postdural puncture headache in young males: A 5-year restrospective study. Indian J Pain 2021;35:235-9

How to cite this URL:
Parikh B, Pande T, Dua A, Sikdar I. Effect of high altitude on the incidence of postdural puncture headache in young males: A 5-year restrospective study. Indian J Pain [serial online] 2021 [cited 2022 Sep 30];35:235-9. Available from: https://www.indianjpain.org/text.asp?2021/35/3/235/334100

  Introduction Top

High altitude is defined differently by different authors with few considering 1500 m and above as high altitude.[1],[2] However, most authors consider only altitudes above 2500 m significant enough to cause considerable physiological changes.[3] High altitude is associated with physiological changes in the body primarily to adapt the body to low oxygen levels and decreasing atmospheric pressure. These significantly affect the human body, especially the cardiopulmonary, hematological, and nervous systems and many studies have enunciated the same. Over the years, internal development and the population explosion has resulted in the inhabitation of remote locations, especially higher altitudes. This has resulted in a greater number of people being exposed to surgery and anesthesia in these extreme locations. Anesthetic management of any patient involves major physiological changes in the body, which needs to be carefully and diligently managed, which is even more challenging in extremes of altitudes. In high altitude, central neuraxial blockade (CNB) in the form of spinal anesthesia (SA) or combined spinal epidural analgesia (CSE) is commonly performed procedure and preferred over general anesthesia (GA) as it has minimum effect on hypobaric hypoxia-associated ventilatory changes.[4] However, CNBs are not devoid of complications, of which postdural puncture headache (PDPH) is the most common.[5] Better understanding of the pathophysiology and improved techniques and needles have helped reduce the incidence over the last few decades. The incidence of PDPH described in literature varies from 0.1% to 36%, implying that a multitude of factors affects the incidence.[6],[7] A recent systemic review and network meta-analysis reported an overall PDPH incidence of 11% when conventional (cutting) needles was used.[8] Numerous studies have studied the mechanism of PDPH, but studies relating to high altitude and its effect on CNBs are scarce. Since cerebrospinal fluid (CSF) leakage is key pathogenesis implicated in the development of PDPH, it is likely that a hypobaric environment and its associated physiological adaptations would influence its occurrence and outcomes This retrospective observational study was carried to study the effect of high altitude on the incidence of PDPH in patients undergoing surgery under SA.

  Materials and Methods Top

Retrospective data of all cases done under SA at a peripheral hospital located at 9600 ft between January 2015 and December 2019 were collected. As the study was retrospective, informed consent for the study was waived off by the committee. All the patients undergoing surgical intervention under SA were included in this study. All the patients were administered SA in L3–L4 or L4–L5 space in sitting position with 26G or 27G Quincke cutting spinal needle. SA was provided with hyperbaric bupivacaine 0.5%. Records were searched for anesthesia consults in the postoperative period. The primary outcome recorded was complaints of headaches reported by patients. The duration of headache, location, associated symptoms, severity, number of attempts, and type of surgical procedure were also analyzed.

Lybecker classification of severity for PDPH was used to classify PDPH as mild moderate and severe:

  1. Mild PDPH

    • Postural headache with slight restriction of daily activities
    • Not bedridden
    • No associated symptoms.

  2. Moderate PDPH

    • Postural headache with significant restriction of daily activities
    • Bedridden part of the day
    • Associated symptoms may or may not be present.

  3. Severe PDPH

    • Postural headache with complete restriction of daily activities
    • Bedridden all day
    • Associated symptoms present (photophobia, diplopia, tinnitus, nausea, vomiting)

All patients had been monitored and discharged on the 7–10th postoperative day as per the hospital policy. The incidence of these complications was calculated and compared with the incidence described in the literature. Patients who were converted to GA were excluded from this study.

Statistical analysis

Distribution of the continuous data was tested with the Kolmogorov–Smirnov one-sample test. Continuous variables with a normal distribution were expressed as mean ± standard deviation. Dichotomous data were expressed as numbers and percentages. For continuous variables, t-test was used for comparing two groups. Chi-square/Fisher's exact test was used for the categorical variables. Statistical analysis was performed using SPSS software (IBM SPSS Statistics 21, Chicago, IL, USA). P < 0.01 was considered statistically significant.

  Results Top

Over a span of 5 years, 572 patients underwent surgery under SA, out of which the data for 132 patients were incomplete and could not be analyzed. 440 patients received SA for various surgical procedures. Among them, in 279 patients, 26G Quincke spinal needle was used, and in the remaining 161, 27G Quincke spinal needle was used. The preoperative characteristics of the patients, duration of surgery, and PDPH incidence are presented in [Table 1].
Table 1: Patient characteristics and surgical duration

Click here to view

A total of 29 patients out of 440 (6.6%) experienced symptoms of PDPH. Of these 29 patients, 20 (7.16%) patients belonged to 26G spinal needle group and 9 patients (5.56%) to 27G spinal needle group. On carrying out the Chi-square test to compare the effect of the size of the needle on PDPH, the difference was not statistically significant (P > 0.01) [Table 2].
Table 2: Patients developing postdural puncture headache on using 26G and 27G needle

Click here to view

The earliest presentation of headache was within 8 h of the surgery. The mean number of days for onset of symptoms was 1.27 ± 0.45 days. The average duration of headache was 72 ± 0.8 h. 72.4% of patients with PDPH (n = 21) reported headache in occipitofrontal region with 82.7% (n = 24) reporting postural aggravation of headache. As described in [Figure 1], 19 patients reported mild PDPH, 8 reported moderate PDPH, and 2 patients reported severe PDPH. In our study, we observed no cases of photophobia, vertigo, tinnitus, or paresthesia in the scalp. There were no differences between the groups with respect to age, weight, ASA grading and duration, and PDPH.
Figure 1: Severity of headache

Click here to view

  Discussion Top

PDPH earlier called as postlumbar puncture headache is defined as headache occurring within 5 days of lumbar puncture caused by CSF leak through the dural puncture. The headache is usually of a dull, throbbing nature with a fronto-occipital distribution, usually aggravated by sitting or standing, and is reduced by lying down.[9] It is accompanied by neck stiffness and/or subjective hearing symptoms with spontaneous recovery within 2 weeks or after sealing the leak with autologous epidural blood patch.[10]

Needle, gender, and age

The incidence of PDPH is influenced by numerous factors, namely age, sex, size of the needle, type of needle, direction of needle, and number of attempts.[11] In the early era, the incidence of PDPH was an alarming 66%, which could be largely attributed to large bore of the needle with cutting tip.[5] With better understanding of the anatomy of dural fibers and the pathophysiology of PDPH, the needle sizes were reduced and tip modified. This led to decreased incidence of PDPH to the current estimate of about <10%.[11]

It is known that cutting needles have a higher incidence of PDPH when compared with atraumatic needles.[12],[13],[14] In two recent systemic reviews, one by Nath et al. reported an overall incidence of PDPH for conventional cutting needle as 11% for needles >20G and an incidence of 3.3% for >26G needles, whereas Zhang et al. reported a cumulative incidence of 6.4% with no subgroup analysis.[8],[15] It is pertinent to note that the above meta-analysis reported an incidence with needles ranging from 20G to 29G Quincke. Our study reported a cumulative incidence of 6.6% patients while using only 26G and 27G Quincke needle. Further analysis revealed that the incidences were 7.16% (20 patients in 279) and 5.56% (9 patients in 161) among patients who were given SA using 26 and 27 G Quincke, respectively.

The observed incidence of PDPH for 26G and 27 G cutting needle has been reported variedly by different authors with Turnbull et al. quoting an incidence of 0.3%–20% and 1.5%–5.6% respectively; however, their data were based on very few studies which were two to three decades old.[16] Most recent studies have reported a far lesser incidence of PDPH than that of our study.[17],[18],[19],[20],[21],[22],[23],[24],[25],[26],[27] However, few studies reported higher incidence when compared to our data; notably, a recent systemic review and network meta-analysis by Maranhao et al. reported an incidence of 7.85% for 26G and 4.01% in 27G cutting needle.[28],[29],[30]

All these studies were conducted at normal altitude and barometric pressures, had mixed gender patients of varying age groups. It is a known fact that the incidence of PDPH is higher in the younger age group with 2–3 times higher female preponderance.[12],[31],[32],[33],[34],[35],[36] In comparison, our study included only young males who underwent surgery under SA in high altitude with reported outcome.


PDPH is usually self-limiting and can be managed conservatively with rest, hydration, and analgesics resulting in good recovery in most patients.[8] Invasive measures like an epidural blood patch with autologous blood with the intent to seal the dural defect have a high success rate, but are reserved as a rescue measure for the most severe cases.

In our study, out of 29 cases of PDPH, 65.51% of cases had only mild PDPH with no additional symptoms, 27.58% had moderate PDPH associated with significant restriction of daily activities and nausea, and 6.89% were having severe PDPH associated with complete restriction of daily activities and nausea and vomiting. All our patients were managed conservatively with no case requiring an epidural blood patch.

Owing to the remote location and poor connectivity, a longer inpatient management was preferred for most postsurgical cases with the usual discharge time ranging between 7 and 10 days after the suture removal. This institutional policy may have ensured better nursing care and compliance to conservative measures leading to favorable outcomes, thus restricting the need for more aggressive management.

Confounding factor: High altitude

High altitude itself is known to cause headache due to primary intracranial hypotension or hypoliquorrhoeic headache. Hyperventilation caused by hypoxia leads to intracranial dehydration, cerebral and retinal venous vasodilatation, and brain engorgement.[37],[38],[39] This may be complicated by intentional dural puncture procedures like SA/CSE. Few case reports and studies have discussed effects of high altitude on anesthesia management and even fewer focused on its effects on SA and PDPH. Being a retrospective study the incidences of prior headaches before the administration of SA could not be taken into consideration.

High altitude induces physiological alterations in the human body in response to hypobaric hypoxia. These changes lead to cerebral vasodilatation and increased CSF pressure and volume. Along with low atmospheric pressure, this may be the cause of increased incidence of PDPH in high altitudes.[40] In a landmark study, Singh et al. invasively studied CSF pressure and observed that CSF pressures increased by about 6–20 cm H2O compared to the baseline values, although all these patients were having symptoms of acute mountain sickness (AMS). Consequently, they concluded that CSF pressure regulatory mechanism is impaired with rapid altitude changes.[41]

In 1964, Safar studied in detail the effects of high altitude on human physiology and its implication on anesthesia. He reported a very high incidence of PDPH at higher altitudes, though at that time, the use of large bore 22G spinal needles was common and could have been a confounding factor.[42] Incidental induction and aggravation of PDPH has been reported in patients who had a history of air travel following a lumbar puncture indicating the association of PDPH and high altitude.[43],[44] During air travel, irrespective of flying altitudes the cabin pressures are regularized to maximum pressures which are equivalent to atmospheric pressures of 2438mts (8000ft), which qualifies as high altitude.[45] These patients reportedly had headache soon after takeoff which improved after landing. They speculated that sudden decompression due to take off would have altered the pressure gradient between dural and barometric pressures sufficient enough to exacerbate PDPH.

In a prospective, multicentric study by Arslan et al., it was observed that PDPH occurs more frequently in high-altitude region when compared to low-lying areas. They reported an incidence almost 30%, which was significant higher when compared with a low altitude group.[46] Similarly, Aksoy et al. reported a PDPH incidence of 7.14% in moderately high altitude.[47] Surprisingly, both these studies were carried out at a modest elevation of 1890 mts (6200 ft), which is not known to cause significant physiological changes, though symptoms of AMS have been reported at altitudes <2400 m. In comparison, our study was carried out at an altitude of about 2900 mts (9500 ft) in male patients with a mean age of 33.45 ± 8.8 years.


There are several limitations to this study, besides being a single-center retrospective study, all the confounding variables could not be considered due to its retrospective nature. SA was administered by different anesthesiologists over the period of 5 years, which was the period of study. Pain perception and evaluation is subjective, so the results may have not been reflected correctly. Since the CSF pressures were not measured by invasive methods, this hypothesis requires to be objectively proven. A multicentric prospective controlled trial in the high altitudes may yield better results and help in better understanding of PDPH in such areas.

  Conclusions Top

This maiden study in a peripheral hospital at high altitude suggests an increased incidence of PDPH among young male patients, possibly due to CSF leak during a state of chronic hypoxia. The use of finer gauge needles has reduced the incidence, frequency, duration, and severity of PDPH. It is suggested that they be used routinely in high altitude areas where the risk of PDPH is apparently higher. Since high altitude physiological changes are primarily associated with a state of chronic hypoxia, intervention in the form of perioperative oxygen administration could be studied to ascertain its correlation with incidence of PDPH. Further randomized controlled trials are needed to establish the effects the high altitude on incidence of PDPH.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.

  References Top

Gabry AL, Ledoux X, Mozziconaci M, Martin C. High altitude pulmonary oedema at moderate altitude (<2400m; 7870ft): A series of 52 patients. Chest 2003;123:49-53.  Back to cited text no. 1
Paralikar SJ, Paralikar JH. High-altitude medicine. Indian J Occup Environ Med 2010;14:6-12.  Back to cited text no. 2
[PUBMED]  [Full text]  
Moore LG, Niermeyer S, Zamudio S. Human adaptation to high altitude: Regional and life-cycle perspectives. Am J Phys Anthropol 1998;Suppl 27:25-64.  Back to cited text no. 3
Leissner KB, Mahmood FU. Physiology and pathophysiology at high altitude: Considerations for the anesthesiologist. J Anesth 2009;23:543-53.  Back to cited text no. 4
Wulf HF. The centennial of spinal anesthesia. Anesthesiology 1998;89:500-6.  Back to cited text no. 5
Kuntz KM, Kokmen E, Stevens JC, Miller P, Offord KP, Ho MM. Post-lumbar puncture headaches: Experience in 501 consecutive procedures. Neurology 1992;42:1884-7.  Back to cited text no. 6
Vilming ST, Kloster R. Post-lumbar puncture headache: Clinical features and suggestions for diagnostic criteria. Cephalalgia 1997;17:778-84.  Back to cited text no. 7
Nath S, Koziarz A, Badhiwala JH, Alhazzani W, Jaeschke R, Sharma S, et al. Atraumatic versus conventional lumbar puncture needles: A systematic review and meta-analysis. Lancet 2018;391:1197-204.  Back to cited text no. 8
Headache Classification Committee of the International Headache Society (IHS). The international classification of headache disorders, 3rd edition (beta version). Cephalalgia 2013;33:629-808.  Back to cited text no. 9
Lybecker H, Djernes M, Schmidt JF. Postdural puncture headache (PDPH): Onset, duration, severity, and associated symptoms. An analysis of 75 consecutive patients with PDPH. Acta Anaesthesiol Scand 1995;39:605-12.  Back to cited text no. 10
Vandam LD, Dripps RD. Long-term follow-up of patients who received 10,098 spinal anesthetics; syndrome of decreased intracranial pressure (headache and ocular and auditory difficulties). J Am Med Assoc 1956;161:586-91.  Back to cited text no. 11
Xu H, Liu Y, Song W, Kan S, Liu F, Zhang D, et al. Comparison of cutting and pencil-point spinal needle in spinal anesthesia regarding postdural puncture headache: A meta-analysis. Medicine (Baltimore) 2017;96:e6527.  Back to cited text no. 12
Buettner J, Wresch KP, Klose R. Post dural puncture headache: Comparison of 25-gauge Whitacre and Quincke needles. Reg Anesth 1993;18:166-9.  Back to cited text no. 13
Arevalo-Rodriguez I, Muñoz L, Godoy-Casasbuenas N, Ciapponi A, Arevalo JJ, Boogaard S, et al. Needle gauge and tip designs for preventing post-dural puncture headache (PDPH). Cochrane Database Syst Rev 2017;4:CD010807.  Back to cited text no. 14
Zhang D, Chen L, Chen X, Wang X, Li Y, Ning G, et al. Lower incidence of postdural puncture headache using whitacre spinal needles after spinal anesthesia: A meta-analysis. Headache 2016;56:501-10.  Back to cited text no. 15
Turnbull DK, Shepherd DB. Post-dural puncture headache: pathogenesis, prevention and treatment. Br J Anaesth 2003;91:718-29.  Back to cited text no. 16
Kang SB, Goodnough DE, Lee YK, Olson RA, Borshoff JA, Furlano MM, et al. Comparison of 26- and 27-G needles for spinal anesthesia for ambulatory surgery patients. Anesthesiology 1992;76:734-8.  Back to cited text no. 17
Corbey MP, Berg P, Quaynor H. Classification and severity of post dural puncture headache. Comparison of 26-gauge and 27-gauge Quincke needle for spinal anaesthesia in day-care surgery in patients under 45 years. Anaesthesia 1993;48:776-81.  Back to cited text no. 18
Malhotra SK, Iyer BA, Gupta AK, Raghunathan M, Nakra D. Spinal analgesia and auditory functions: A comparison of two sizes of Quincke needle. Minerva Anestesiol 2007;73:395-9.  Back to cited text no. 19
González Santillan JM, Cedillo Maguey A, Cárdenas Jurado J, Gómez Ortiz I, Cortés Rosas NE. Post puncture headache in young ambulatory patients, comparing two different kinds of spinal anesthesia needles for lower limb surgery. Rev Mex Anestesiol 2000;23:161-6.  Back to cited text no. 20
Tarkkila P, Huhtala J, Salminen U. Difficulties in spinal needle use. Insertion characteristics and failure rates associated with 25-, 27- and 29-gauge Quincke-type spinal needles. Anaesthesia 1994;49:723-5.  Back to cited text no. 21
Brattebø G, Wisborg T, Rodt SA, Røste I. Is the pencil point spinal needle a better choice in younger patients? A comparison of 24G Sprotte with 27G Quincke needles in an unselected group of general surgical patients below 46 years of age. Acta Anaesthesiol Scand 1995;39:535-8.  Back to cited text no. 22
Schultz AM, Ulbing S, Kaider A, Lehofer F. Postdural puncture headache and back pain after spinal anesthesia with 27-gauge Quincke and 26-gauge Atraucan needles. Reg Anesth 1996;21:461-4.  Back to cited text no. 23
Puolakka R, Jokinen M, Pitkanen MT, Rosenberg PH. Comparison of post-anesthetic sequelae after clinical use of 27 gauge cutting and non-cutting spinal needles. Reg Anesth 1997;22:521-6.  Back to cited text no. 24
de Diego Fernández R, Tisner Madrid ML, Cabrerizo Torrente P, Sanjoaquín Mur T. Comparison of two 27-G-caliber needles for spinal anesthesia. Study of 1,555 patients. Rev Esp Anestesiol Reanim 2003;50:182-7.  Back to cited text no. 25
Santanen U, Rautoma P, Luurila H, Erkola O, Pere P. Comparison of 27-gauge (0.41-mm) Whitacre and Quincke spinal needles with respect to post-dural puncture headache and non-dural puncture headache. Acta Anaesthesiol Scand 2004;48:474-9.  Back to cited text no. 26
Srivastava V, Jindal P, Sharma JP. Study of post dural puncture headache with 27G Quincke and Whitacre needles in obstetrics/non obstetrics patients. Middle East J Anaesthesiol 2010;20:709-17.  Back to cited text no. 27
Pirbudak L, Ozcan HI, Tumturk P. Postdural puncture headache: Incidence and predisposing factors in a university hospital. J Turk Soc Algol 2019;31:1-8.  Back to cited text no. 28
Chaudhry M, Ahmad R, Qureshi Z. Postdural puncture headache comparative study between 25 guage pencil point needle and 25 gauge quincky needle. Pak J Med Health Sci 2011;5:50-4.  Back to cited text no. 29
Maranhao B, Liu M, Palanisamy A, Monks DT, Singh PM. The association between post-dural puncture headache and needle type during spinal anaesthesia: A systematic review and network meta-analysis. Anaesthesia 2021;76:1098-110.  Back to cited text no. 30
Amorim JA, Gomes de Barros MV, Valença MM. Post-dural (post-lumbar) puncture headache: Risk factors and clinical features. Cephalalgia 2012;32:916-23.  Back to cited text no. 31
Castrillo A, Tabernero C, García-Olmos LM, Gil C, Gutiérrez R, Zamora MI, et al. Postdural puncture headache: Impact of needle type, a randomized trial. Spine J 2015;15:1571-6.  Back to cited text no. 32
Alstadhaug KB, Odeh F, Baloch FK, Berg DH, Salvesen R. Post-lumbar puncture headache. Tidsskr Nor Laegeforen 2012;132:818-21.  Back to cited text no. 33
Reid JA, Thorburn J. Headache after spinal anaesthesia. Br J Anaesth 1991;67:674-7.  Back to cited text no. 34
Lynch J, Krings-Ernst I, Strick K, Topalidis K, Schaaf H, Fiebig M, et al. Use of 25 guage whitacre needle to reduce the incidence of postdural puncture headache. Br J Anaesth 1991;67:690-3.  Back to cited text no. 35
Wu CL, Rowlingson AJ, Cohen SR, Michaels RK, Courpas GE, Joe EM, et al. Gender and post-dural puncture headache. Anesthesiology 2006;105:613-8.  Back to cited text no. 36
Wilson MH, Davagnanam I, Holland G, Dattani RS, Tamm A, Hirani SP, et al. Cerebral venous system and anatomical predisposition to high-altitude headache. Ann Neurol 2013;73:381-9.  Back to cited text no. 37
Calbet JA. Chronic hypoxia increases blood pressure and noradrenaline spillover in healthy humans. J Physiol 2003;551:379-86.  Back to cited text no. 38
Batsis JA, Phy MP. Intracranial hypotension: Aggravation of headache at high altitude. Headache 2005;45:380-4.  Back to cited text no. 39
Senay LC Jr., Tolbert DL. Effect of arginine vasopressin, acetazolamide, and angiotensin II on CSF pressure at simulated altitude. Aviat Space Environ Med 1984;55:370-6.  Back to cited text no. 40
Singh I, Khanna PK, Srivastava MC, Lal M, Roy SB, Subramanyam CS. Acute mountain sickness. N Engl J Med 1969;280:175-84.  Back to cited text no. 41
Safar P, Tenicela R. High altitude physiology in relation to anesthesia and inhalation therapy. Anesthesiology 1964;25:515-31.  Back to cited text no. 42
Panadero A, Bravo P, García-Pedrajas F. Postdural puncture headache and air travel after spinal anesthesia with a 24-gauge Sprotte needle. Reg Anesth 1995;20:463-4.  Back to cited text no. 43
Porhomayon J, Zadeii G, Yarahamadi A, Nader ND. A case of prolonged delayed postdural puncture headache in a patient with multiple sclerosis exacerbated by air travel. Case Rep Anesthesiol 2013;2013:253218.  Back to cited text no. 44
Brundrett G. Comfort and health in commercial aircraft: A literature review. J R Soc Promot Health 2001;121:29-37.  Back to cited text no. 45
Arslan Z, Kutanis D, Ozkan AR, Aslan M, Erturk E. The Effect of Geographic Altitude on Frequency of Postdural Puncture Headache. Prospective Multicentric Study. J Clin Anesth Manag 2016;1(5).  Back to cited text no. 46
Aksoy M, Ince I, Ahıskalıoglu A, Karaca O, Bayar F, Erdem AF. Spinal anaesthesia at low and moderately high altitudes: A comparison of anaesthetic parameters and hemodynamic changes. BMC Anesthesiol 2015;15:123.  Back to cited text no. 47


  [Figure 1]

  [Table 1], [Table 2]


Similar in PUBMED
   Search Pubmed for
   Search in Google Scholar for
 Related articles
Access Statistics
Email Alert *
Add to My List *
* Registration required (free)

  In this article
Materials and Me...
Article Figures
Article Tables

 Article Access Statistics
    PDF Downloaded78    
    Comments [Add]    

Recommend this journal