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Three Part Question

In [patients with cardiac arrest after cardiac surgery] is [external cardiac massage or internal massage] better in generating optimal [cardiac index and coronary perfusion]?

Clinical Scenario

A 52 year old patient 36-hours after mitral valve repair and grafts arrests with an asystolic ECG. He had been on increasing doses of adrenaline and a TOE had shown a poor LV but no tamponade. After 2-minutes of external cardiac massage and 1mg of adrenaline you elect to perform an emergency re-sternotomy with the intention of putting the patient back on bypass. Once commencing internal massage you are surprised at the significantly better arterial pressure that you are able to achieve performing internal massage.

Search Strategy

Medline 1950-Oct 2007 using the OVID interface.
[open chest.mp OR internal cardiac.mp OR resuscitative thoracotomy.mp OR open heart.mp ] AND [CPR.mp OR exp Cardiopulmonary resuscitation/ or massage.mp]
EMBASE 1980–Oct 2007 using the OVID interface.
[open chest.mp OR internal cardiac.mp OR resuscitative thoracotomy.mp OR open heart.mp ] AND [CPR.mp OR exp resuscitation/ or massage.mp]
The Cochrane database for systematic reviews and central register of controlled trials was searched using the term 'open chest', or 'internal cardiac' or CPR.

Search Outcome

263 papers were found in Medline, 256 in EMBASE and 8 articles in the Cochrane library . Of these, 22 were felt to be relevant and 15 were tabulated

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
ILCOR consensus on science, 2005, Worldwide	International Liaison Committee on Resuscitation Advanced Life Support Task force recommendation	(Level 4, excellent, positive) Systematic review of cohort studies, case series and animal studies	Consensus on science	2 human studies after cardiac surgery and 2 out of hospital arrest have been published. The observed benefits of open-chest cardiac massage included improved coronary perfusion pressure and increased return of spontaneous circulation. Evidence from animal studies indicates that open-chest CPR produces greater survival rates, perfusion pressures, and organ blood flow than closed chest CPR
			Treatment recommendations	Open-chest CPR should be considered for patients with cardiac arrest in the early post-operative phase after cardiothoracic surgery or when the chest or abdomen is already open.
			Class of recommendation	Class IIb: Acceptable and useful, fair evidence
Anthi et al, 1998, Greece	29 patients with cardiac arrest within 24 hours of cardiac surgery. Closed chest CPR initiated, if no ROSC after 3 to 5 minutes, open chest CPR commenced.	(level 4, good, positive) Consecutive Cohort Study	Incidence of ROSC and survival	Closed chest CPR successful in 13 patients. Of remaining 16, open chest CPR was successful in 14. Four patients did not survive to discharge. At one year, 20/23 patients were alive. Overall causes were myocardial infarction (14), cardiac tamponade (5), graft malfunction (3) and unknown (7).	This study does not directly compare the usefulness of closed chest CPR versus open chest CPR.
Pottle et al, 2002, UK	72 post cardiac surgery patients undergoing OCCC.	(Level 4, good, positive) Consecutive cohort study	Outcome	Initial survival was 33/72 (46%). Only 12/72 (17%) survived to discharge. No patients receiving OCCC outside HDU survived.	No direct comparison of CCCC and OCCC
Takino 1993, Japan	95 patients with non-traumatic out-of-hospital cardiac arrest, 26 patients had open chest CPR after failed closed chest CPR.	(Level 4, fair, positive) Controlled Cohort Study.	Return of Spontaneous Circulation	Closed Chest CPR 21/89 patients (30%). Open Chest CPR 15/26 patients (58%).	Not randomised. Authors felt numbers were too low for statistical analysis.
			Hospital discharge	Closed Chest CPR 1/89 patients (1%). Open Chest CPR 3/26 patients (12%)
			Timing of chest opening	Tendency to improved outcomes if chest opened within 5 minutes.
Hachimi-Idrissi et al, 1997, Belgium	33 patients with out-of-hospital cardiac arrest, undergoing open-chest-CPR after failure of closed chest CPR. These 33 patients are collected out of a series of 2212 patients on their database.	(Level 5, fair, positive) Case Series	ROSC and survival	ROSC was achieved in 13 patients. Two of these survived to hospital discharge.	Very selected cases. Only 2 survivors.
Del Guercio et al, 1965, USA	11 human subjects with in hospital cardiac arrest.	(Level 5, fair, positive) Case-Series	Cardiac index.	Closed Chest CPR 0.61 l/min/m2. Open Chest CPR 1.31 l/min/m2	Not randomised. Old study
			Circulation time	Closed Chest CPR 43.8 secs. Open Chest CPR 88.5 secs p<0.01
Calinas-Correia et al, 2001, UK	7 patients who had non traumatic cardiac arrest out-of-hospital. Once entering hospital Open chest CPR performed by one physician	(Level 5, poor , neutral.) Case-series	Oxygenation	pO2 was physiological or supra-physiological in all patients
			Acid base balance	This was not corrected in these patients
			Survival	3 attained spontaneous circulation but no survivors
Geehr et al, 1986, USA	49 patients with out of hospital cardiac arrest, randomised to CCCC or OCCC.	Letter about an RCT (unknown level of evidence)	Survival	Three patients in each group were resuscitated and admitted to hospital. No patient in either group survived to discharge.	Letter format only, no published study details
Benson et al, 2005, USA	12 dogs with induced ventricular fibrillation. After five minutes of non-intervention, subjects randomised to receive 15 mins of closed chest CPR or 15 mins of open chest CPR. Defibrillation was then attempted and resuscitation continued.	(Level 6, excellent, positive) An experimental animal study – randomised controlled trial	Dog survival	Open Chest CPR All 5 dogs survived and neurologically normal at 72 hours Closed Chest CPR 3/7 dogs survived but one had ataxia and the other 2 had severe neurological deficits
			Coronary perfusion pressure	Open Chest CPR 38.2mmHg. Closed chest CPR 20.3mmHg
Rubertsson et al, 2005, Sweden	ILCOR worksheet titled : Open chest CPR improves outcome when compared with standard closed-chest CPR. 22 articles included after full systematic review [Sanders]	(Level 4, excellent, positive) Systematic review of cohort studies, case series and animal studies	Level of evidence	Class IIb : Acceptable and useful, fair evidence
			Recommendation	Open-chest CPR results in greater perfusion pressures and systemic, organ blood flows and survival and may be indicated in cases of circulatory arrest in the early postoperative phase after cardiothoracic surgery or when the chest or abdomen is already open (transdiaphragmal approach) for example in trauma surgery Open-chest CPR may also be necessary in victims of avalanche accidents with cardiac arrest and deep hypothermia since external thoracic compressions are not efficient due to stiff thoracic cage
			Quality and direction of studies	18 level 6 papers, 1 level 5, 2 level 4 and a level 3 study of which 4 were human studies, were found all in support of the hypothesis.
Sanders et al, 1984, USA	10 dogs in ventricular fibrillation. Closed Chest CPR for 15 minutes Dogs with coronary perfusion pressure below 30mmHg had thoracotomy and internal massage for 3 minutes. Closed chest massage in the others All dogs defibrillated at 20 mins	(Level 6, good, positive) An experimental animal study.	Successful resuscitation and survival to 20 minutes, aortic and right atrial pressure	Open Chest CPR 4/5 dogs resuscitated Closed Chest CPR No survivors Significant differences in arterial or coronary pressure.	Very small numbers in each group.
Kern et al, 1987, USA	28 mongrel dogs put into ventricular fibrillation. All had 15 mins of regular CPR, then randomised to closed or open chest CPR for a further 2 minutes followed by Defibrillation.	(Level 6, excellent, positive) Experimental animal study	Aortic pressure	Open Chest CPR 112/70. Closed Chest CPR 48/25, p<0.001
			Coronary perfusion	Open Chest CPR 65mmHg. Closed Chest CPR 19mmHg P<0.001
			Return of spontaneous circulation	Open Chest CPR 14/14 dogs. Closed Chest CPR 5/14 dogs P<0.05
			24 hour survival	Open Chest CPR 12/14 dogs. Closed Chest CPR 4/14 dogs P<0.05
Kern et al, 1991, USA	Twenty mongrel dogs. Ten animals underwent 20 mins of VF and were then randomised into open or closed chest CPR. The other 10 animals all underwent open chest CPR.. In half of these, this was instituted after 10 mins of VF, in the other half, after 40 mins.	(Level 6, good, positive) Experimental Animal Study	Survival	Open Chest CPR after 10 minutes 5/5 dogs. Open Chest CPR after 20 mins 5/5 dogs. Open Chest CPR after 40 mins 0/5 dogs. Closed Chest CPR 1/5 dogs
			Physiological variables	OCCC produced significantly better coronary perfusion and aortic pressures. These values were also significantly better in the OCCC 20 min group in comparison with the 40 min group.
Mackay et al, 2004, UK	79 post cardiac surgery patients who underwent chest reopening during cardiac arrest	(Level 4, excellent, positive) Consecutive cohort study	ROSC and survival to discharge	Overall survival to discharge was 20/79 (25%). Survival was more likely if arrest occurred within 24 hours of surgery (39% vs 13% p=0.02) and with chest reopening within 10 min of arrest (48% vs 12% p<0.001). No patients arresting on ward survived	No direct comparison

Comment(s)

The International Liaison Committee on Resuscitation which comprehensively reviewed 276 topics in resuscitation with 281 experts in the field in 2005 looked at the issue of open versus closed chest cardiac massage, and provided a systematic review on the topic as part of their worksheet review process. They found 4 human studies, with 2 in cardiac surgery and 2 in out-of-hospital cardiac arrest and 18 animal studies. They report that there are observed benefits of open-chest-cardiac massage including improved coronary perfusion pressure and increased return of spontaneous circulation in humans and better survival rates, and organ blood flow as compared to closed-chest CPR. They recommend that open-chest-CPR should be considered for patients for cardiac arrest in the early postoperative phase after cardiothoracic surgery or when the chest or abdomen is already open(Class IIb). The two human studies after cardiac surgery referred to were by Anthi and Pottle. Anthi provided a report of 29 patients who arrested less than 24 hours after cardiac surgery. 45% were resuscitated with closed-chest-CPR and 48% with open-chest-CPR after 2-5minutes of closed-chest massage had failed. Pottle reported 72 patients who had open-chest-CPR after cardiac surgery, of whom 46% regained spontaneous circulation. Of the other 2-human studies, Boczar studied 10-patients brought into hospital with a witnessed cardiac arrest. After 5-minutes of closed-chest-CPR they were declared unsalvageable and entered into the study. A left lateral thoracotomy was performed without opening the pericardium and internal massage commenced. The mean coronary perfusion pressure rose from 7.3mmHg to 32mmHg, the compression-phase pressure gradient rose from 6.2mmHg to 32.6mmHg and 3-patients obtained a spontaneous circulation. They remind us that Paradis in JAMA reported that 15mmHg of coronary perfusion is required in humans to obtain a return of spontaneous circulation, this was achieved in all Boczar's patients during open-chest-CPR. Paradis also reported 3-patients who had open-chest-CPR after failed closed-chest-CPR and 2-survived, one with no neurological deficit. Takino compared 26-patients who had open-chest-CPR after witnessed out-of-hospital cardiac arrest with 69 who just had closed-chest-CPR. 58% of patients had spontaneous return of circulation with open-chest-CPR compared with 30% with closed-chest-CPR. There were 3 open-chest long-term survivors compared to only one closed-chest survivor. A third human study rejected by ILCOR was by Hachimi-Idrissi. They found 33 patients who had open-chest-CPR after failed closed-chest-CPR in their database of 2212 out-of-hospital arrest patients. 13 had spontaneous return of circulation but only 2 survived. We identified 3 additional human studies. Del Guercio in 1965 showed significant improvements in physiological variables with open-chest-CPR in 11-patients with in-hospital arrest. The cardiac index was 0.6 l/min/m2 with closed-chest-CPR but was 1.3 l/min/m2 with open-chest-CPR. The circulation time decreased from 89 seconds to 44 seconds. Calinas-Correia reported 7-patients who underwent open-chest CPR but with no survivors. Geehr in a letter reported in the NEJM that they had performed an RCT of 49 patients with an out-of-hospital arrest and found 3-survivors in the open-chest-CPR group, and 3 in the closed-chest-CPR group. Of the animal studies Benson induced VF in 12-dogs and after 5-minutes of no intervention randomized the dogs to either open or closed-chest-massage for 15-minutes. All open-chest-CPR dogs survived without neurological deficit but only 3/7 dogs survived after closed-chest-CPR and 2 had severe neurological deficit. The coronary perfusion pressure was double in the open-chest-CPR group. Sanders showed that open-chest-CPR allowed 4/5 dog survivors compared to none in their closed-chest group. Kern showed that resuscitation and survival were significantly improved with open cardiac massage in 29 dogs and reiterated these findings in 1991, adding that resuscitation was significantly improved if chest opening was instituted sooner. Raessler in 63-mongrel dogs showed that open-chest-CPR had a coronary perfusion pressure of 64mmHg compared to 21mmHg for closed-chest massage. Rubertsson showed significant improvements in cardiac index and coronary perfusion pressure in 35-pigs.

Clinical Bottom Line

Over 18 good quality animal studies have consistently demonstrated the superiority of open chest cardiac massage, with the cardiac index and coronary perfusion pressures often more than doubling. There are fewer human studies but they have shown that closed-chest-massage generates a cardiac index of around 0.6 which rises to 1.3 l/min/m2 or more with open-chest-CPR, accompanied by even bigger improvements in coronary perfusion pressure. ILCOR recommends prompt conversion to open-chest-cardiac massage in patients shortly post-cardiac surgery, and we would support this intervention if simple resuscitative efforts such as defibrillation, pacing or atropine fail, in order to significantly improve the quality of cardiopulmonary resuscitation.

References

1. International Liaison Committee on Resuscitation., International Liaison Committee on Resuscitation. 2005 International Consensus on Cardiopulmonary Resuscitation and Emergency Cardiovascular Care Science with Treatment Recommendations. Part 4: Advanced life support. [601 refs]. Resuscitation 2005;67(2-3):213-47.
2. Anthi A, Tzelepis GE, Alivizatos P et al. Unexpected cardiac arrest after cardiac surgery: incidence, predisposing causes, and outcome of open chest cardiopulmonary resuscitation.[see comment]. Chest 1998;113(1):15-9.
3. Pottle A, Bullock I, Thomas J et al. Survival to discharge following open chest cardiac compression (OCCC). A 4-year retrospective audit in a cardiothoracic specialist centre--Royal Brompton and Harefield NHS Trust, United Kingdom. Resuscitation 2002;52(3):269-72.
4. Boczar ME, Howard MA, Rivers EP et al. A technique revisited: hemodynamic comparison of closed- and open-chest cardiac massage during human cardiopulmonary resuscitation. Crit Care Med 1995;23(3):498-503.
5. Paradis NA, Martin GB, Rivers EP. Coronary perfusion pressure and the return of spontaneous circulation in human cardiopulmonary resuscitation. JAMA 1990;263:1105-13.
6. Paradis NA, Martin GB, Rivers EP. Use of open chest cardiopulmonary resuscitation after failure of standard closed chest CPR: illustrative cases. Resuscitation 1992;24(1):61-71.
7. Takino M, Okada Y. The optimum timing of resuscitative thoracotomy for non-traumatic out-of-hospital cardiac arrest. Resuscitation 1993;26(1):69-74.
8. Hachimi-Idrissi S, Leeman J, Hubloue Y et al. Open chest cardiopulmonary resuscitation in out-of-hospital cardiac arrest. Resuscitation 1997;35(2):151-6.
9. Del Guercio LR, Feins NR, Cohn JD et al. Comparison of blood flow during external and internal cardiac massage in man. Circulation 1965;31:SUPPL-80.
10. Calinas-Correia J, Phair I. Physiological variables during open chest cardiopulmonary resuscitation: results from a small series.[see comment]. J Accid Emerg Med 2000;17(3):201-4.
11. Geehr EC, Lewis FR, Auerbach PS. Failure of open-heart massage to improve survival after prehospital nontraumatic cardiac arrest. N Engl J Med 1986;314(18):1189-90.
12. Benson DM, O'Neil B, Kakish E et al. Open-chest CPR improves survival and neurologic outcome following cardiac arrest. Resuscitation 2005;64(2):209-17.
13. Sanders AB, Kern KB, Ewy GA. Time limitations for open-chest cardiopulmonary resuscitation from cardiac arrest. Crit Care Med 1985;13(11):897-8.
14. Kern KB, Sanders AB, Badylak SF. Long-term survival with open-chest cardiac massage after ineffective closed-chest compression in a canine preparation. Circulation 1987;75(2):498-503.
15. Raessler KL, Kem KB. Aortic and right atrial systolic pressures during cardiopulmonary resuscitation : a potential indicator of the mechanism of blood flow. Am Heart J 1988;115(5):1021-9.
16. Rubertsson S, Grenvik A. Blood flow and perfusion pressure during open-chest versus closed-chest cardiopulmonary resuscitation in pigs. Crit Care Med 1995;23(4):715-25.
17. Sanders AB, Kern KB, Ewy GA et al. Improved resuscitation from cardiac arrest with open-chest massage. Ann Emerg Med 1984;13(9 Pt 1):672-5.
18. Kern KB, Sanders AB, Ewy GA. Open-chest cardiac massage after closed-chest compression in a canine model: when to intervene. Resuscitation 1987;15(1):51-7.
19. Kern KB, Sanders AB, Janas W et al. Limitations of open-chest cardiac massage after prolonged, untreated cardiac arrest in dogs. Ann Emerg Med 1991;20(7):761-7.
20. Mackay JH, Powell SJ, Osgathorp J et al. Six-year prospective audit of chest reopening after cardiac arrest. Eur J Cardiothorac Surg 2002;22(3):421-5.
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