Does pleurotomy during internal mammary artery harvest increase post-operative pulmonary complications?

Date First Published:
May 3, 2005
Last Updated:
May 16, 2005
Report by:
Mark Wheatcroft, Vivek Shrivastava, Brian Nyawo, Anthony Rostron, Specialist Registrars in Cardiothoracic Surgery (Cardiovascular Research Unit, Sheffield University, Department of Cardiothoracic Surgery, James Cook University Hospital, Freeman Hospital, Newcastle)
Search checked by:
Joel Dunning, Cardiovascular Research Unit, Sheffield University, Department of Cardiothoracic Surgery, James Cook University Hospital, Freeman Hospital, Newcastle
Three-Part Question:
Does [pleurotomy] during [IMA harvest] increase the incidence of [post-operative pulmonary complications]?
Clinical Scenario:
You are a first year cardiothoracic registrar who is starting to work for a consultant surgeon who always prefers the pleura to remain intact whilst harvesting the internal mammary artery (IMA). The surgeon avoids pleurotomy to reduce pulmonary complications after cardiac surgery, but you wonder whether there is any evidence in the literature to support this practice
Search Strategy:
Medline 1966-Oct 2004 using the OVID interface.
Search Details:
[cardiac surgery.mp OR CABG.mp OR coronary art$ bypass graft$.mp OR cardiopulmonary bypass.mp OR exp cardiovascular surgical procedures/ OR heart surgery.mp OR LIMA.mp] AND [exp Pleura/ OR Pleura$.mp OR extrapleur$.mp OR pleurotomy.mp]
Outcome:
One hundred and fifty-four papers were found of which 19 were relevant. Eleven papers were discounted as they did not compare IMA harvest with intact pleura versus IMA harvest with open pleura, and thus did not directly address the question. There were no meta-analyses on this topic. Three RCTs were identified and the remainder were all cohort studies with small sample/population sizes. These are presented in the table
Relevant Paper(s):
Study Title Patient Group Study type (level of evidence) Outcomes Key results Study Weaknesses
Opening the pleura during internal mammary artery harvesting: advantages and disadvantages. Ali IM, Lau P, Kinley CE, Sanalla A. 1998 Canada 280 patients for elective coronary revascularization using IMA
Group I (n=30) pleura intact
Group II (n=50) pleurotomy
Single centre PRCT (level 1b) Pleural effusion on days 0 and 3 Group I 7/130. Group II 30/150 P<0.001 No effusions required tapping
5 group II patients required opening for tamponade
Preop FEV1 <80% excluded
Significant pneumonia or atelectasis defined as need for antibiotic therapy or ventilatory support
Postoperative bleeding 4% in both groups
Significant pneumonia or atelectasis None in both groups
Hospital stay Group I 6-10 days. Group II 6-10 days. No significant difference
Effect of internal thoracic artery preparation on blood loss, lung function and pain. Wimmer-Greinecker G, Yosseef-Hakimi M, Rinne T, Buhl R, Matheis G, Martens S, Westphal K, Moritz A. 1999 Germany 112 patients for coronary revascularization
Group A (n=57) pleurotomy
Group B (n=55) pleura intact
Single centre PRCT (level 1b) Blood loss Group A 608±58 ml. Group B 470±48 ml P=0.027
Lung function Greater reduction in FEV1 (Group A 76.0%±1.6 vs Group B 83.2%±1.6; p=0.002). FEV1/FVC (Group A 0.771±0.021 vs Group B 0.832±0.02; P=0.003)
Pleural effusion and atelectasis Effusion A=52.6%, B=23.6% (P=0.002). Atelectasis A=42.1%, B=20% (P=0.015)
Extrapleural takedown of the internal mammary artery as a pedicle. Noera G, Pensa PM, Guelfi P, Biagi B, Lodi R, Carbone C. 1991 Italy 433 CABG with IMA
Group 1: Open pleura
Group 2: Extrapleural takedown with pleura intact
Single centre PRCT (level 1b) Transfusion requirements Significantly lower transfusion rate in group 2
Postop effusions, elevated hemidiaphragm Lower but not significant rates of effusion and elevated hemidiaphragm in group 2 vs 1
Respiratory dysfunction after coronary artery bypass grafting and employing bilateral internal mammary arteries: the influence of the intact pleura. Bonnacchi M, Prifti E, Giunti G, Salica A, Frati G, Sani G. 2001 Italy 299 elective patients undergoing coronary revascularization
Group I (n=80) skeletonized IMA, intact pleura
Group II (n=179) pedicled IMA, open pleura
Group III (n=30), skeletonized IMA, open pleura
Cohort study (level 2b) Mechanical ventilation time Significantly longer in groups II (6.2±2.9 h) and III (6.0±1.1 h) vs I (5.4± 1.2 h); P<0.018, P<0.02 respectively EF <30% excluded
12 in group I with repair of pleura
Decision to skeletonize IMA based on surgeon's experience
If there were small breaches of the pleura these were repaired and included in group I
Analysis only for surviving patients; 2 died in group I, 7 in II, 1 in III
Pmax >20 cm H2O Significant difference in group II (3.2±1 h) vs I (2.3±0.6 h) P=0.001
Prolonged ventilation (>24 h) Significant difference in group II (16/179) vs I (1/80) P=0.03
Pleural effusion Significant difference in group II (31/186) vs I (5/82) P=0.011
Thoracocentesis Significant differences in groups II (31/179) and III (7/30) vs I (5/80) (P=0.027, P<0.027, respectively)
Atelectasis during ICU Significant difference in group II (37/179) vs I (6/80) P<0.013
Intensive care stay Group I 1.03±0.5 d. Group II 1.4±0.7 d. Group III 1.35±0.4 d. I vs II P=0.005. I vs III P=0.002
Pulmonary complications following myocardial revascularization with the internal mammary graft. Landymore RW and Howell F. 1990 Canada 106 patients
Group 1: 39 valve/SVG
Group 2: 34 IMA + pleurotomy
Group 3: 33 IMA pleurae intact
Cohort study (level 3b) Diaphragmatic elevation a) prior to discharge 1-21%; 2-77%; 3-24% No statistical analysis
Diaphragmatic elevation b) at three months 1-5%; 2-47%; 3-6%
Pleural effusions a) prior to discharge 1-26%; 2-91%; 3-58%
Pleural effusions b) at three months 1-3%; 2-15%; 3-0%
Study of pulmonary function after CABG with pleurotomy. Tomita S, Sakata R, Umebayasi Y, Miyata A, Terai H, Ueyama K, Uezu T. 1994 Japan 99 elective CABG
Group 1: 45 BIMA + pleurotomy
Group 2: 45 IMA + pleurotomy
Group 3: 9 IMA/SVG no pleurotomy
Cohort study (level 3b) PFTs and CXR post op No CXR differences between 3 groups. All patients had significant reductions in PFTs but no differences between groups
Effect of pleurotomy on pulmonary function after coronary artery bypass grafting with internal mammary artery. Rolla G, Fogliati P, Bucca C, Brussino L, Di Rosa E, Di Summa M, Comoglio C, Malara D, Ottino GM. 1994 Italy 57 IMA patients
Group 1: 32 with pleurotomy
Group 2: 25 pleurae intact
Cohort study (level 3b) Atelectasis on POD 2&6 CXRs 1–22% & 29%; 2–19% & 19% Not significant Small study. No clinical data.
Data described as a percentage of preop value.
There was no significant difference in preop values between the two groups.
Pleural Effusion on POD 2&6 CXRs 1–74% & 48%; 2–52% & 38%; Not significant
Raised hemidiaphragm on POD 6 CXRs 1–18.5%; 2–14%; Not significant
PFTs 2 months postop VC: 1–86.8±1.97; 2–93.6±1.65; P=0.05. FEV1: 1–84.6±1.82; 2–90.9±1.41 P=0.02
A prospective study on clinical outcome following pleurotomy during cardiac surgery. Lim E, Callaghan C, Motalleb-Zadeh R, Wallard M, Misra N, Ali A, Halstead JC, Tsui S. 2002 UK 206 elective patients
Group I Routine or incidental pleurotomy (n=164)
Group II Pleura intact (n=38)
Cohort study (level 3b) Left lung atelectasis Significantly higher in pleurotomy group (67.7%) vs intact pleura (45.2%) P=0.007. Heterogeneous group
No randomization
Small intact pleura group
Effusion Pleura intact 46%. Pleura open 43%. P=0.66
Hospital stay 9 days both groups
Author Commentary:
The majority of relevant studies assessed the effect of pleurotomy on post-operative lung function, ventilatory requirements and radiographic changes. Only three studies considered the effect of pleurotomy on clinical outcome [Norea, Lim and Ali et al]. In addition, the lengths of post-operative follow-up varied extensively from 30 min to 3 months. We identified three PRCTs that compared IMA plus pleurotomy to IMA without pleurotomy.

The largest PRCT was conducted by Noera et al, the only significant outcome being greater transfusion requirements in the pleurotomy group, although they did find that the rate of pleural effusion and raised left hemidiaphragm was greater albeit not significant in the same group. This study is further supported by Ali et al and Wimmer-Greinecker et al. In the study undertaken by Ali et al., they found that the pleurotomy group had significantly more pleural effusions but that this did not result in more thoracocenteses. Pleurotomy also safe-guarded against the development of cardiac tamponade, with 5 in the closed group but none in the open pleura group. Another clinically relevant outcome was that hospital stay was not different between the two groups.


Lim et al assessed post operative chest radiology and length of stay in a heterogeneous group that comprised 138 CABG, 39 valve replacements and 29 CABG + valve replacement. Patients were divided into those with pleurotomy(n=164) and those without (n=42). The pleurotomy group had significantly more atelectasis (67.7% vs. 45.2%, P<0.007) but there was no difference in rates of consolidation, effusion or length of stay.


In a relatively small study, Rolla et al recruited 57 patients all of whom had an IMA conduit, therefore blinding chest radiograph reporting. The two groups were of similar size, 32 with pleurotomy, 25 without. There was no difference in post-op chest radiograph on day 2 or 6 and all patients were found to have significantly worse PFTs persisting at 2 months post operation.

Tomita et al divided 99 elective CABG cases into 45 BIMA + pleurotomy, 45 IMA + pleurotomy and 9 IMA/SVG only with no pleurotomy and studied PFTs and post-operative chest radiograph changes. There were no differences between groups with all patients suffering significant reductions in PFTs.
Bottom Line:
All patients undergoing cardiac surgery suffer a significant deterioration in Pulmonary Function tests and chest radiograph appearance post-operatively. Pleurotomy seems to compound this with increased rates of atelectasis and pleural effusions, although no impact on clinical outcome or length of hospital stay has been demonstrated.
References:
  1. Ali IM, Lau P, Kinley CE, Sanalla A.. Opening the pleura during internal mammary artery harvesting: advantages and disadvantages.
  2. Wimmer-Greinecker G, Yosseef-Hakimi M, Rinne T, Buhl R, Matheis G, Martens S, Westphal K, Moritz A.. Effect of internal thoracic artery preparation on blood loss, lung function and pain.
  3. Noera G, Pensa PM, Guelfi P, Biagi B, Lodi R, Carbone C.. Extrapleural takedown of the internal mammary artery as a pedicle.
  4. Bonnacchi M, Prifti E, Giunti G, Salica A, Frati G, Sani G.. Respiratory dysfunction after coronary artery bypass grafting and employing bilateral internal mammary arteries: the influence of the intact pleura.
  5. Landymore RW and Howell F.. Pulmonary complications following myocardial revascularization with the internal mammary graft.
  6. Tomita S, Sakata R, Umebayasi Y, Miyata A, Terai H, Ueyama K, Uezu T.. Study of pulmonary function after CABG with pleurotomy.
  7. Rolla G, Fogliati P, Bucca C, Brussino L, Di Rosa E, Di Summa M, Comoglio C, Malara D, Ottino GM.. Effect of pleurotomy on pulmonary function after coronary artery bypass grafting with internal mammary artery.
  8. Lim E, Callaghan C, Motalleb-Zadeh R, Wallard M, Misra N, Ali A, Halstead JC, Tsui S.. A prospective study on clinical outcome following pleurotomy during cardiac surgery.