It’s been 12 years since we gave you a review of the researchcomparing suction with simple gravity drainage for postoperativelung surgery patients, so it’s clearly time for an update. We’vereviewed 20 articles; 6 are reviews of the literature and 14 arestudies comparing suction and gravity drainage.Set the Ground Rules

It’s challenging to compare these research studies because“water seal” or “gravity” drainage doesn’t necessarily mean thechest drain was never connected to suction. In many studies, therandomization to suction or no suction occurs the morning of POD1 after overnight suction. In other studies, patients do not use suc-tion during the day but do at night.1 For ease of discussion, we willuse “suction” to mean the chest drain is connected to an externalvacuum source that applies a negative pressure of -10 cmH2O ormore in the pleural space. “Gravity” means the drain is not con-nected to external vacuum. Remember, though, if you go back tothese original sources, you’ll need to examine each one carefullyto learn that study’s terms.When is a Pneumothorax not a Pneumothorax?

In older studies, the main assessment was whether there wasa pneumothorax on CXR. Treatment was based on routine CXRexams, even if the patient was asymptomatic.2-5 But researchersare now suggesting the area without lung markings on CXR is notnecessarily a pneumothorax, but instead, a “fixed pleural spacedeficit.”6,7 Most lung resections are done on patients with preexist-ing lung disease, and the lack of elasticity or compliance of theremaining lung, chest wall, and/or diaphragm may prevent theremaining lung tissue from expanding to fill the space left after theresection.6,8 Or, the CXR may be reflecting atelectasis and partiallung collapse as a result of sputum retention in the small airwayspostoperatively.8 Either way, pleural suction is not going to resolvethe deficit.4,7,8 More recently, studies report CXR are only done ifthe patient’s condition worsens. If the patient is newly hypoxic,short of breath or developing subcutaneous emphysema, suctionis applied to the chest drain regardless of CXR results.6,9

Another researcher suggests that suction delays healing bydrawing air from the lung through an actual or potential opening(between staples) in the parenchyma that prevents approximationof the parenchymal wound edges and limits primary wound heal-ing.10 And a group of Japanese surgeons suggests the increasedfluid drainage from pleural tubes with suction results from pleuralirritation, not “better drainage” of existing postop fluids.5

As recently as 2001, a leading researcher had to use a compli-cated study protocol because his institutional review board wouldnot let him put patients on gravity drainage without a period of suc-tion first – they considered the practice unethical because of a“preconceived notion that a pneumothorax with an air leak wasbad.”2,11 Fortunately, we have overcome that hurdle today.

Examining the ResearchNine studies directly compared suction and gravity.1,3,8-10,12-15

While they had a variety of study designs, they did look at com-mon outcomes, including the duration of chest tube, duration of airleak, hospital length of stay, and whether or not there was a “pro-longed air leak” (number of days defined by the author). Of thenine, four placed all patients on suction before randomizing.1,9,14,15

Only one study found statistically significant outcomes in favorof suction;1 these surgeons use an alternating suction protocol inwhich patients “on suction” are disconnected during the day andonly receiving suction overnight, so the “suction” patients wereactually on gravity drainage more than half the time. Three studiesfound no statistically significant differences between thegroups,8,12,14 and one was limited to the number of patients withprolonged air leaks, and then only found a difference (in favor ofgravity) when patients who had lobectomy or segmentectomy(n=396) were pulled out of the whole group (n=500; p=0.05).9

While not all studies measured each outcome, in the remainingfour studies3,10,13,15 shorter duration of chest tube, shorter durationof air leak, shorter length of stay, and fewer patients with prolongedair leak (PAL) all favored the gravity drainage group with (statisti-cal significance).Literature Reviews

Three of the six literature reviews extracted data and performedmeta-analysis.16-18 All three reviewed five common stud-ies,2,3,8,11,14 and each included one other study.12,15,19 There wasno difference detected between suction and gravity for duration ofair leak, incidence of prolonged air leak, duration of chest tube(s),and hospital length of stay. A review of the literature on treatingpneumothorax concluded clinical objectives can be accomplishedwith either needle aspiration or tube drainage via gravity.20

Finally are two “state of the art” reviews.7,21 One examined theeffect of suction on prolonged air leak and concluded that no stud-ies were in favor of suction, two found no difference, and four werein favor of gravity drainage.21 In the other, the author states, “[grav-ity drainage was] not only safe for air leaks but also seemedsuperior to suction at stopping leaks in patients who maintained …pleural apposition.” “Patients who had their tubes placed on waterseal … instead of wall suction … were more likely to have theirleak stop.” In summary, “randomized studies have shown thatplacing chest tubes to water seal … is superior to suction and bet-ter at stopping air leaks when a pneumothorax does not occurwhen patients are placed to water seal [however]; a pneumotho-rax itself is not an indication for suction because many patientshave a fixed pleural space deficit.”7

Suction not Required?None of these researchers recommends suction for all patients

following lung surgery. Typical recommendations include: “Webelieve minimizing duration of suction has resulted in decreasedduration of air leak and number of patients with PAL,”10 and “rou-tine application of… suction … is not necessary after lobectomy…

Suction or Gravity? Revisited

Clinical Update is edited by Patricia Carroll, MS, RN-BC, CEN, RRT, andsupported by an educational grant from Atrium Medical Corporation.

Spring 2014

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Spring 2014

In the LiteratureImplementation Science for EBPThe current issue of Orthopaedic Nursing provides a useful summa-ry explaining how nurses can use the principles of implementationscience (IS) to facilitate the change process necessary to provideup-to-date, evidence-based care at the bedside. The authors relatetheir experience changing practice related to identifying and manag-ing delirium. The IS model allowed them to identify barriers andshortcomings and how to correct them. Source: Powrie SL, et al: Using implementation science to facilitate evidence-based practice changes to promote optimal outcomes for orthopaedic patients.Orthopaedic Nursing 2014;33(2):109-114. PubMed Citation

But We Didn’t Know!A group of Georgia nurses conducted a national survey to identifyfactors that influenced nurses’ adoption of AACN’s evidence-basedguidelines on tube feeding placement verification. Only 55% of the370 respondents were aware of the guidelines, and only 29% fol-lowed the four practices supported. Nurses with BSN or higher weretwice as likely to comply, and the guideline characteristics of observ-ability (the innovation is visible to others) and trialability (nurses couldtry out the innovation) enhanced adoption. This research will helpnurses design more effective EBP implementation plans.Source: Bourgault AM: Factors influencing critical care nurses’ adoption of theAACN practice alert on verification of feeding tube placement. American Journalof Critical Care 2014;23(2):134-143. PubMed Citation

EBP Unintended Consequences?Colorado nurses highlight a potentially serious “translation” problemin the current Journal of Emergency Nursing. To enhance safety formedication dosing, the hospitals focused on ensuring that all weightswere in kilograms. Part of the process was removing scales thatmeasured pounds and ounces. While all children were weighed, low-risk adults were asked their weight, which was always in pounds. Theelectronic medical record only accepted kilogram weights. The nextchallenge was that parents couldn’t understand how much their childweighed. The nurse would convert the weight to pounds for the fam-ily, which introduced the potential error that the nurse wouldremember and record the weight in pounds rather than kg. To solvethe problem, conversion cards were created and placed with thescales. The nurses circle the weight in kg and give it to the parent whocan see the conversion factor. This report is a terrific reminder that“simple” changes can still be filled with potential hidden dangers.Source: Stone-Griffith S, et al: Unintended practice consequences of applying evi-dence-based change. Journal of Emergency Nursing 2014;40(2):190-192.PubMed Citation

We’re pleased to announce that Managing ChestDrainage, our 2.0 credit online continuing educationactivity is back! The monograph is fully updated with aversion optimized for mobile or tablet use, and if youdon’t finish the activity in one sitting, you can log backin and complete when you like, on any device. Onceyou register, you can log in to your profile for a recordof your activity, and if you need another certificate, youcan print it at any time. We’re working on building alibrary of CE activities for you this year. Simply click onthe link at www.AtriumU.com.

It is of no help in persistent air leaks when the lung is expanded …[and] we advocate no use of routine suction in patients undergoinglobectomy.”8 Other authors state, “the water seal method … [is] asafe and effective method for treating postoperative air leaks.”5“Although the majority of physicians favored … suction when apatient has an air leak after lung resection … water seal is superi-or,”6 and “We have adopted a policy … of not adding suction …unless it is specifically judged to be indicated.”11 Two researcherspoint out that reducing routine suction also eases nursing work-load.3,11

Marshall and colleagues sum it up best, “The data presentedhere, combined with previously reported data … provide com-pelling evidence that placing chest tubes on suction routinely afterpulmonary resection is counterproductive.”3

Sources1. Brunelli A, A Sabbatini, F Xiume, et al.: Alternate suction reduces prolonged air leak after pulmonary

lobectomy: a randomized comparison versus water seal. Ann Thorac Surg 2005;80(3):1052-1055.PubMed Citation

2. Cerfolio RJ, C Bass, CR Katholi: Prospective randomized trial compares suction versus water sealfor air leaks. Ann Thorac Surg 2001;71(5):1613-1617. PubMed Citation

3. Marshall MB, ME Deeb, JI Bleier, et al.: Suction vs water seal after pulmonary resection: a random-ized prospective study. Chest 2002;121(3):831-835. PubMed Citation FREE FULL TEXT

4. Sakamoto T, W Nishio, M Okada, et al.: Management of air leak after pulmonary resection. Jpn JThorac Cardiovasc Surg 2004;52(6):292-295. PubMed Citation

5. Okamoto J, T Okamoto, Y Fukuyama, et al.: The use of a water seal to manage air leaks after a pul-monary lobectomy: a retrospective study. Ann Thorac Cardiovasc Surg 2006;12(4):242-244.PubMed Citation FREE FULL TEXT

6. Cerfolio RJ, AS Bryant, S Singh, CS Bass, AA Bartolucci: The management of chest tubes inpatients with a pneumothorax and an air leak after pulmonary resection. Chest 2005;128(2):816-820. PubMed Citation FREE FULL TEXT

7. Cerfolio RJ, AS Bryant: The management of chest tubes after pulmonary resection. Thorac SurgClin 2010;20(3):399-405. PubMed Citation

8. Prokakis C, EN Koletsis, E Apostolakis, et al.: Routine suction of intercostal drains is not necessaryafter lobectomy: a prospective randomized trial. World J Surg 2008;32(11):2336-2342. PubMedCitation

9. Leo F, L Duranti, L Girelli, et al.: Does external pleural suction reduce prolonged air leak after lungresection? Results from the AirINTrial after 500 randomized cases. Ann Thorac Surg2013;96(4):1234-1239. PubMed Citation

10. Bertholet JW, JJ Joosten, ME Keemers-Gels, FJ van den Wildenberg, WB Barendregt: Chest tubemanagement following pulmonary lobectomy: change of protocol results in fewer air leaks. InteractCardiovasc Thorac Surg 2011;12(1):28-31. PubMed Citation FREE FULL TEXT

11. Alphonso N, C Tan, M Utley, et al.: A prospective randomized controlled trial of suction versus non-suction to the under-water seal drains following lung resection. Eur J Cardiothorac Surg2005;27(3):391-394. PubMed Citation

12. Brunelli A, M Salati, C Pompili, M Refai, A Sabbatini: Regulated tailored suction vs regulated seal: aprospective randomized trial on air leak duration. Eur J Cardiothorac Surg 2013;43(5):899-904.PubMed Citation

13. Antanavicius G, J Lamb, P Papasavas, P Caushaj: Initial chest tube management after pulmonaryresection. Am Surg 2005;71(5):416-419. PubMed Citation

14. Brunelli A, M Monteverde, A Borri, et al.: Comparison of water seal and suction after pulmonarylobectomy: a prospective, randomized trial. Ann Thorac Surg 2004;77(6):1932-1937; discussion1937. PubMed Citation

15. Ayed AK: Suction versus water seal after thoracoscopy for primary spontaneous pneumothorax:prospective randomized study. Ann Thorac Surg 2003;75(5):1593-1596. PubMed Citation

16. Deng B, Q Tan, Y Zhao, R Wang, Y Jiang: Suction or non-suction to the underwater seal drains fol-lowing pulmonary operation: meta-analysis of randomised controlled trials. Eur J Cardiothorac Surg2010;38:210-215. PubMed Citation FREE FULL TEXT

17. Coughlin SM, HM Emmerton-Coughlin, R Malthaner: Management of chest tubes after pulmonaryresection: a systematic review and meta-analysis. Can J Surg 2012;55(4):264-270. PubMedCitation FREE FULL TEXT

18.Qiu T, Y Shen, MZ Wang, et al.: External suction versus water seal after selective pulmonary resec-tion for lung neoplasm: a systematic review. PLoS One 2013;8(7):e68087. PubMed Citation FREEFULL TEXT

19. Kakhki AD, M Pooya, S Pejhan, et al.: Effect of chest tube suction on air-leak following lung resec-tion. Tanaffos 2006;5(1):37-43.

20. Kaneda H, T Nakano, Y Taniguchi, et al.: Three-step management of pneumothorax: time for a re-think on initial management. Interact Cardiovasc Thorac Surg 2013;16(2):186-192. PubMedCitation FREE FULL TEXT

21. Sanni A, A Critchley, J Dunning: Should chest drains be put on suction or not following pulmonarylobectomy? Interact Cardiovasc Thorac Surg 2006;5(3):275-278. PubMed Citation FREE FULLTEXT

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