Correspondence / American Journal of Emergency Medicine 37 (2019) 762–793

Novel method of infant chest compression. Does the arrangement of the thumbs matter??

Dear Editor,

769

Following the discussion [1-3] on a novel technique for chest com- pression in infants and newborns (nTTT), described in the American Journal of Emergency Medicine [4], we decided to examine whether the angle of chest compression in accordance with the technique affected the basic quality parameters of resuscitation. Infant chest compression with nTTT is described as follows: “the ‘new two-thumb technique’ (nTTT) of chest compressions in an infant consists in using two thumbs directed at the angle of 90? to the chest while closing the fingers of both hands in a fist” [5]. Observing the discussion on nTTT, we paid special at- tention to the angle of thumbs in relation to the chest wall. The main ad- vantage of the new technique is that the alignment of thumbs with the arms increases the compressive force exerted on the chest, which in the case of the two-finger technique mainly depends on the muscle strength of the fingers and the whole hand. We therefore decided to compare the basic chest Compression quality parameters during infant resuscitation.

After receiving an approval by the Institutional Review Board of the Polish Society of Disaster Medicine (approval no.: IRB N 12.07.2018), we performed a cross-over randomized manikin study in a group of 36 paramedics. Each participant received information about the study and voluntarily agreed to participate. The subjects were to perform single-rescuer 2-min cardiopulmonary resuscitation with the use of an ALS Baby trainer manikin (Laerdal Medical, Stavanger, Norway) simulating a 3-month-old infant. In order to allow comparison with previous studies, the manikin was placed on a high adjustable hospital stretcher at the level of the Iliac crest of each rescuer for standardization. The resuscitation was performed in accordance with the current pediatric basic life support Resuscitation guidelines (15:2 chest compression to ventilation rate with the recommended 100-120 chest compressions per minute). The study involved 2 scenarios; the participants were randomly assigned to performing resuscitation with both scenarios in a randomly assigned order with a 20-min break before applying the other CPR technique. Scenario A consisted in implementing the correct nTTT chest compression technique with two thumbs directed at the angle of 90? to the chest while closing the fingers of both hands in a fist. Scenario B included a modified nTTT technique with two thumbs directed at the angle of 45? instead of 90? (Fig. 1). We evaluated chest compression depth, chest compression rate, percentage of compressions with correct depth, percentage of chest compressions with the recommended rate, and percentage of complete chest relaxation. The data were analyzed with the Statistica software

v.12 (StatSoft Inc., Tulsa, USA). The Research Randomizer software (www.randomizer.org) was used for randomization. The median depth (mm) of chest compression was 39 (37-40) in scenario A and 36 (35-39) in Scenario B (p = 0,009), and the percentage of compres- sions with correct depth (%) achieved equaled 79 (59-86) vs 64 (57-81) (p = 0.018) in scenarios A and B, respectively. The chest com- pression rate (compressions per minute) turned out 116 (110-122) vs 113 (103-126) (p = NS), and the percentage with the recommended rate (%) was 92 (83-94) vs 93 (80-92) (p = 0,031) in scenarios A and B, respectively. The percentage of complete chest relaxation (%) was 99 (98-100) in scenario A and 94 (83-97) in scenario B (p = 0,047). In our study, the median chest compression depth was better that with the modified incorrect nTTT and almost achieved the recom- mended 40 mm. The same appeared with the percentage of compres- sions with correct depth and percentage of complete chest relaxation. Our preliminary results indicate that the angle at which the rescuer

? Source of support: No sources of financial and material support to be declared.

Fig. 1. New infant chest compression technique: two thumbs directed at the angle of 45?

(A) instead of 90? (B).

directs the thumbs to the chest is important in nTTT and can influence the results. Our results suggest that when comparing nTTT with other techniques, including the 2-finger technique (TFT) recommended for lone rescuer and the 2-thumb-encircling hands technique (TTHT), it is very important to ascertain that the correct nTTT chest compression technique with 2 thumbs directed at the angle of 90? to the chest while closing the fingers of both hands in a fist is used; otherwise it can impede the results.

Kurt Ruetzler

Department of Outcomes Research, Anesthesiology Institute, Cleveland

Clinic, Cleveland, USA Department of General Anesthesiology, Anesthesiology Institute, Cleveland

Clinic, Cleveland, USA

Jacek Smereka

Department of Emergency Medical Service, Wroclaw Medical University,

Wroclaw, Poland

Lukasz Szarpak

Faculty of Medicine, Lazarski University, Warsaw, Poland

770 Correspondence / American Journal of Emergency Medicine 37 (2019) 762–793

Michael Czekajlo

Hunter Holmes McGuire VA Medical Center, Department of Surgery,

Richmond, United States Corresponding author at: Hunter Holmes McGuire VA Medical Center, Department of Surgery, 1201 Broad Rock Blvd, Richmond, VA 23249,

United States.

E-mail address: [email protected].

7 August 2018

https://doi.org/10.1016/j.ajem.2018.08.030

References

1. Rodriguez-Ruiz E, Guerra Martin V, Abelairas-Gomez C, Sampedro Vidal F, Gomez Gonzalez C, Barcala-Furelos R, et al. A new chest compression technique in infants. Med Int 2018;pii: S0210-5691(18). https://doi.org/10.1016/j.medin.2018.04.010 30154-2. [Epub ahead of print].
2. Oh JH. What is the best chest compression technique for infant cardiopulmonary re- suscitation? Am J Emerg Med 2017;35(5):794-5.
3. Smereka J, Szarpak L, Smereka A, Leung S, Ruetzler K. New method of infant

   chest compression. Authors response. Am J Emerg Med 2017;35(5):795. https://doi.org/10.1016/j.ajem.2016.12.068 (Epub 2016 Dec 29. No abstract available).

   Smereka J, Szarpak L, Smereka A, Leung S, Ruetzler K. Evaluation of new Two-thumb chest compression technique for infant CPR performed by novice physicians. A ran- domized, crossover, manikin trial. Am J Emerg Med 2017;35(4):604-9. https://doi. org/10.1016/j.ajem.2016.12.045 [Epub 2016 Dec 19].

4. Smereka J, Szarpak L, Smereka A, Leung S, Ruetzler K. Evaluation of new two-thumb chest compression technique for infant CPR performed by novice physicians. A ran- domized, crossover, manikin trial. Am J Emerg Med 2017;35(4):604-9. https://doi. org/10.1016/j.ajem.2016.12.045 [Epub 2016 Dec 19].

   Diabetes mellitus and hypoglycemia as a complication of Intravenous insulin to treat hyperkalemia in the ED

   We read with interest the article by Scott NL et al. “Hypoglyce- mia as a complication of intravenous insulin to treat hyperkalemia in the emergency department” that have been published in the American Journal of Emergency Medicine [1]. This interesting retro- spective study reports on the rate of hypoglycemia following intra- venous insulin treatment for hyperkalemia in the emergency department setting and furthermore describes which variables were independently associated with this outcome: Lower glucose level prior to insulin administration, higher doses of administrated insulin and lower doses of administered 50%dextrose were inde- pendently associated with hypoglycemia in the multivariate analy- sis. Age, history of diabetes, and history renal failure were not independently associated.

   The authors of the study have collected and analyzed a large amount of data, leading to interesting debate. Nevertheless, we would like to ad- dress them one question that may contribute to further, more detailed discussion of the issue.

   The authors as well as in several other studies [2,3], involved di- abetes mellitus into the analysis as one disease. But diabetes mellitus is a group of metabolic diseases resulting from various pathogenic defects which may be treated by different ways and therefore a risk of hypoglycemia may differ between individual patients.

   Based on our clinical experience we can speculate that the highest risk of hypoglycemia after insulin administration due to treatment of hyperkalemia is associated with type 1 diabetes

   patients. The main reasons for our believe are 1) these patients are at higher risk of hypoglycemia due to insulin treatment itself simply said due to failure to clear circulating insulin during hypoglycaemia (this may probably explain 4% of patients experiencing hypoglycemia without i.v. insulin administration mentioned in the study) and hyperkalemia related insulin dose may interfere with previously injected insulin by a patient;

   2) lower glucose threshold for release of counterregulatory hor- mones; and (4) loss of normal pancreatic alpha cell responses

   [4]; 3) impaired awareness of hypoglycaemia which may be pres- ent in 30% and even more patients [4-6], 4) usually good insulin sensitivity [4] (making them more sensitive to even smaller doses of insulin, moreover if they are added to their regular daily doses).

   Therefore we believe that it would be interesting to analyze this group of patients to evaluate the risk of hypoglycemia related to hyperkalemia treatment with insulin separately. Because above mentioned disorders 1-3 are also to some extent presented in type 2 diabetes patients [4,7], those treated with insulin or sulphonylurea derivates could also be an interesting focus on analysis.

   We, with great respect, suggest taking these comments into the ac- count and also consider them, if the continuation of the study is planned.

   Funding

   This article was supported by Ministry of Health, Czech Republic Grant No. 00064203 – conceptual development of re- search organization, Motol University Hospital, Prague, Czech Republic.

   Conflict of interest statement

   The authors do not have any conflicts of interest to declare.

   Acknowledgments

   Special thanks to Rob Smith for language editing.

   Jan Broz, MD Department of Internal Medicine, Second Faculty of Medicine, Charles University, V Uvalu 84, 150 00 Prague, Czech Republic Corresponding author: Dep Int Med, Second Faculty of Medicine, Charles University, V Uvalu 84, 150 00 Prague, Czech Republic.

   E-mail address: [email protected].

   Jana Urbanova, MD, PhD Ludmila Brunerova, MD, PhD

   Second Department of Internal Medicine, Center for Research of Diabetes, Metabolism and Nutrition, Third Faculty of Medicine, Charles University, University Hospital Kralovske Vinohrady, Ruska 97, 106 00 Prague,

   Czech Republic

   Marisa Nunes Department of Internal Medicine, Second Faculty of Medicine, Charles University, V Uvalu 84, 150 00 Prague, Czech Republic

   5 August 2018

   https://doi.org/10.1016/j.ajem.2018.08.032