My opinion

By Dr. Deepak Gupta
Corresponding Author Dr. Deepak Gupta
Wayne State University, - United States of America 48201
Submitting Author Dr. Deepak Gupta

Incentive Spirometry, Combined Spinal Epidural, Laryngeal Mask Airway, Endotracheal Tube Cuff Pressure, Loss Of Resistance Epidural Space

Gupta D. Anecdotes: Postoperative-Incentive-Spirometry, CSE-Introducer-Needle, Triangulated-LMA-Circuit-Support, Cuff-Pressure-Self-Deflating-Syringe, No-Injection-of-Air-Technique. WebmedCentral ANAESTHESIA 2020;11(2):WMC005603

This is an open-access article distributed under the terms of the Creative Commons Attribution License(CC-BY), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Submitted on: 18 Feb 2020 05:00:22 PM GMT
Published on: 26 Feb 2020 10:22:53 AM GMT


The author is indebted to his teachers who all taught him about anesthesiology over the years especially Vitaly D. Soskin, MD, PhD and Elie J. Chidiac, MD.

My Opinion

Everyone has their own anecdotes. The following clinical vignettes are my anecdotes. Some of them were inspired by my teachers while some of them were inspired by my students. Some of them were inspired by my kin while some of them have originated de novo. Altogether, these anecdotes seemed worth sharing with my peers and therefore, here they are.


First anecdote:


I have always appreciated that how wonderfully incentive spirometry has had helped my near and dear ones to increase their pulmonary capacities. Therefore, if people at homes can gain with the institution of incentive spirometry in their regular days, the patients at hospitals must definitely benefit in their postoperative pulmonary recovery with as needed institution of postoperative incentive spirometry. Although it may not be universally indicated for all postoperative patients [1-3], it may sometimes help when indicated in particular patients’ pathophysiology to ensure healthcare providers’ confidence in pulmonary recovery of those particular patients back to their preoperative baselines especially when such patients are being discharged with their incentive spirometers in tow to their homes so that they can continue their pulmonary recovery at home baselines after having initiated towards it in the recovery areas inside the hospitals.


Second anecdote:


Spinal anesthesia needles are becoming thinner and thinner in gauge for our patients’ comfort while our patients’ intrathecal spaces are getting deeper and deeper to access during the ongoing global obesity epidemic [4-8]. Spinal spaces gain further depths when pregnancy-induced weight gains further make it difficult to impossible to palpate or locate surface markers to appropriately guide spinal anesthesia needles’ access [9-10]. Even though spinal introducer needles allow the introduction of thinner spinal anesthesia needles across them, it becomes impossible to walk-off the bony interference with thin spinal anesthesia needles especially when spinous processes, laminas, transverse processes or even pedicles are encountered at extreme depths during the spinal anesthesia needle access in obese pregnant patients. To avoid starting from the scratch by withdrawing the spinal anesthesia needles back inside the spinal introducer needles and renegotiating the spinal introducer needles’ angles despite failing in multiple attempts to aim the spinal anesthesia needles towards extreme depths of intrathecal spaces, combined spinal epidural (CSE) needle sets can be used wherein thicker epidural needles act as longer spinal introducer needles with clear end-points being inside patients’ epidural spaces as compared to regular shorter spinal introducer needles remaining confined to undefined depths of subcutaneous tissues [11]. Moreover, it becomes easier to walk-off the bony interferences when encountered by the thicker epidural needles walking-off towards intrathecal spaces surrounded by bony spinous processes, laminas, transverse processes and pedicles. When the primary aim becomes to provide dense spinal anesthesia with no intention to leave epidural catheters in situ if CSE needle sets are being used as mentioned above, CSE-needle induced inadvertent large-hole dural punctures’ incidence may be avoided by prematurely testing for intrathecal spaces’ access with thinner spinal anesthesia needles through thicker epidural needles even when the thicker epidural needles may have given in false loss-of-resistance because even though the epidural needle may be located shallower than the needles truly located inside epidural spaces, they may still be much more appropriately located by being much more deeper than regular shorter spinal introducer needles.          


Third anecdote:


Laryngeal mask airways (LMAs) are secured centrally in the midline inside patients’ oro-laryngopharynx. When the anesthesia circuits are connected to them from one side or the other side of the operating tables, there seems to be inadvertent drags on LMAs potentially risking the well-sealed LMAs cuffs to move away from their central positions covering patients’ laryngeal openings into inadequate-seal positions on one side or the other side inside patients’ laryngopharynx. To limit maladjusted movements of LMAs’ cuffs [12-13], the internal-central-midline positions of LMAs may be externally ensured and supported by triangulating the anesthesia circuits towards the patients’ chest wherein patients’ chests act as the caudal bases of the schematic equilateral triangles with inspiratory and expiratory limbs of anesthesia circuits acting as the other two adjacent sides of the schematic equilateral triangles and Y-pieces of anesthesia circuits acting as the cranial apexes/vertexes of the schematic equilateral triangles. After encountering patients’ chests completing the schematic equilateral triangles, the remaining lengths of the inspiratory limbs and the expiratory limbs of anesthesia circuits can make U-turns at patients’ chests to move around the both sides of patients’ heads to be finally anchored onto the anesthesia circuits’ breathing tubes’ holding and supporting tube trees centrally situated at operating tables’ head ends just cranial to patients’ heads.


Fourth anecdote:


Just like the previous anecdote, this anecdote has been my teachers’ teachings which I have been trying to follow to-a-t [14-16]. Compared to places where cuff pressure gauges/manometers are readily available to quantitatively measure and to periodically correct the endotracheal tube cuff pressures, the places where such instruments are not readily available can qualitatively protect against overinflated endotracheal tube cuffs by leaving the cuff inflating syringes connected to the pilot balloons for few moments after inflating endotracheal tube cuffs so that these syringes can act as self-deflators of extra air getting instilled into the endotracheal tube cuffs whereby extra air can automatically find its way back into the attached syringes because the luer-locks of the syringes may be momentarily allowing the bypassing of pilot balloons’ one-way valves not only during the inflation of endotracheal tube cuffs but also during self-deflation of overinflated endotracheal tube cuffs to potentially normalize as much as possible the cuff-volumes and cuff-pressures in the endotracheal tube cuffs depending on individual patients’ tracheas’ sizes.  


Final anecdote (at least for now):


Finally, it took me sometime to self-realize and understand and promulgate after observing uniquely successful teachers and uniquely successful students that while teaching loss-of-resistance techniques for recognizing epidural spaces during epidural needle accesses and combined spinal-epidural needle accesses, it may have to become mandatory to go back to the original constant pressure methods wherein the loss of resistance is just that loss of resistance and nothing like injection of substance especially not injection of air [17-22]. It takes sometime to appreciate the subtle loss of resistance and over time the level of appreciation improves with the number of procedures. However, the injections of air or even injections of saline do not serve any purposes in regarding to confirming the initially appreciated loss of resistance except making them (injected air and/or saline) problematic for post-procedure safety of the patients (by leaving injected air where it’s not needed physiologically and may be even pathological for the patients) and true successes of the epidural accesses (if solution dripping out of epidural needles can be confused to be just the injected saline when it may actually be the inadvertent dural puncture related cerebrospinal fluid). Instead of injections of air or saline to confirm the initially felt loss of resistance, the epidural needles may be withdrawn a few millimeters posteriorly towards the entry site and thereafter epidural spaces may be re-accessed with the second or may be even third time confirmatory appreciations of subtle losses of resistance. 


Summarily, these may be my anecdotes but like my inspirations from my kin, my students and my teachers, these anecdotes may inspire others to consider and develop their own anecdotes to validate for appropriateness and thereafter share the appropriate anecdotes with their peers, students and teachers.


  1. Tyson AF, Kendig CE, Mabedi C, Cairns BA, Charles AG. The effect of incentive spirometry on postoperative pulmonary function following laparotomy: a randomized clinical trial. JAMA Surg. 2015 Mar 1;150(3):229-36. doi: 10.1001/jamasurg.2014.1846.
  2. do Nascimento Junior P, Módolo NS, Andrade S, Guimarães MM, Braz LG, El Dib R. Incentive spirometry for prevention of postoperative pulmonary complications in upper abdominal surgery. Cochrane Database Syst Rev. 2014 Feb 8;(2):CD006058. doi: 10.1002/14651858.CD006058.pub3.
  3. Armstrong CO. Post-op incentive spirometry: Why, when, & how. Nursing. 2017 Jun;47(6):54-57. doi: 10.1097/01.NURSE.0000516223.16649.02.
  4. Fama' F, Linard C, Bierlaire D, Gioffre'-Florio M, Fusciardi J, Laffon M. Influence of needle diameter on spinal anaesthesia puncture failures for caesarean section: A prospective, randomised, experimental study. Anaesth Crit Care Pain Med. 2015 Oct;34(5):277-80. doi: 10.1016/j.accpm.2015.05.005.
  5. Herbstman CH, Jaffee JB, Tuman KJ, Newman LM. An in vivo evaluation of four spinal needles used for the combined spinal-epidural technique. Anesth Analg. 1998 Mar;86(3):520-2.
  6. Ravi KK, Kaul TK, Kathuria S, Gupta S, Khurana S. Distance from Skin to Epidural Space: Correlation with Body Mass Index (BMI). J Anaesthesiol Clin Pharmacol. 2011 Jan;27(1):39-42.
  7. Adegboye MB, Bolaji BO, Ibraheem GH. The Correlation Between Body Mass Index On The Length From Skin To Lumbar Epidural Space In Nigerian Adults. J West Afr Coll Surg. 2017 Jan-Mar;7(1):113-127.
  8. Zobel EH, Hansen TW, Rossing P, von Scholten BJ. Global Changes in Food Supply and the Obesity Epidemic. Curr Obes Rep. 2016 Dec;5(4):449-455.
  9. American College of Obstetricians and Gynecologists. ACOG Committee opinion no. 548: weight gain during pregnancy. Obstet Gynecol. 2013 Jan;121(1):210-2. doi: http://10.1097/01.AOG.0000425668.87506.4c.
  10. American College of Obstetricians and Gynecologists. ACOG Committee opinion no. 549: obesity in pregnancy. Obstet Gynecol. 2013 Jan;121(1):213-7. doi: http://10.1097/01.AOG.0000425667.10377.60.
  11. Ahn WS, Bahk JH, Lim YJ, Kim YC. The effect of introducer gauge, design and bevel direction on the deflection of spinal needles. Anaesthesia. 2002 Oct;57(10):1007-11.
  12. Kim J, Kim JY, Kim WO, Kil HK. An ultrasound evaluation of laryngeal mask airway position in pediatric patients: an observational study. Anesth Analg. 2015 Feb;120(2):427-32. doi: 10.1213/ANE.0000000000000551.
  13. Van Zundert AA, Kumar CM, Van Zundert TC. Malpositioning of supraglottic airway devices: preventive and corrective strategies. Br J Anaesth. 2016 May;116(5):579-82. doi: 10.1093/bja/aew104.
  14. Annoni R, Pires-Neto RC. Ineffectiveness of using the pressure relief valve technique during cuff inflation. Rev Bras Ter Intensiva. 2014 Oct-Dec;26(4):367-72. doi: 10.5935/0103-507X.20140056.
  15. Mac Murdo SD, Buffington CW. Brand and size matter when choosing a syringe to relieve pressure in a tracheal tube cuff. Anesth Analg. 2004 Nov;99(5):1445-9.
  16. Somri M, Fradis M, Malatskey S, Vaida S, Gaitini L. Simple on-line endotracheal cuff pressure relief valve. Ann Otol Rhinol Laryngol. 2002 Feb;111(2):190-2.
  17. Dogliotti AM. Research and Clinical Observations on Spinal Anesthesia: With Special Reference to the Peridural Technique. Current Researches in Anesthesia & Analgesia. 1933 Mar-Apr;12(2):59-65.
  18. Duffy BL. Pain during epidural analgesia. Anaesthesia. 1984 Sep;39(9):941. doi: 10.1111/j.1365-2044.1984.tb06608.x
  19. Shah JL. Unexplained pain during epidural analgesia. Anaesthesia. 1984 Aug;39(8):844. doi: 10.1111/j.1365-2044.1984.tb06561.x
  20. Saberski LR, Kondamuri S, Osinubi OY. Identification of the epidural space: is loss of resistance to air a safe technique? A review of the complications related to the use of air. Reg Anesth. 1997 Jan-Feb;22(1):3-15.
  21. Antibas PL, do Nascimento Junior P, Braz LG, Vitor Pereira Doles J, Módolo NS, El Dib R. Air versus saline in the loss of resistance technique for identification of the epidural space. Cochrane Database Syst Rev. 2014 Jul 18;(7):CD008938. doi: 10.1002/14651858.CD008938.pub2.
  22. Carvalho LP, Agarwal A, Kashiwagi FT, Corrêa I, Pereira JE, El Dib R. Commonly-used versus less commonly-used methods in the loss of resistance technique for identification of the epidural space: A systematic review and meta-analysis of randomized controlled trials. J Clin Anesth. 2017 May;38:41-51. doi: 10.1016/j.jclinane.2017.01.017.

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