Psychiatric complications of cardiac surgery postoperative delirium syndrome

Diagnostic accuracy of the "4 A's Test" delirium screening tool for the postoperative cardiac surgery ward

BACKGROUND

Delirium is prevalent and underdetected among cardiac surgery patients on the postoperative ward. This study aimed to validate the 4 A's Test delirium screening tool and evaluate its accuracy both when used by research assistants and when subsequently implemented by nursing staff on the ward.

METHODS

This single-center, prospective observational study evaluated the performance of the 4 A's Test administered by research assistants (phase 1) and nursing staff (phase 2). Assessments were undertaken during the patients' first 3 postoperative days on the postcardiac surgery ward along with previous routine nurse-led Confusion Assessment Method assessments. These index tests were compared with a reference standard diagnosis of delirium based on Diagnostic and Statistical Manual of Mental Disorders 5th Edition criteria. Surveys regarding delirium screening were administered to nurses pre- and postimplementation of the 4 A's Test in phase 2 of the study.

RESULTS

In phase 1, a total of 137 patients were enrolled, of whom 24.8% experienced delirium on the postoperative cardiac ward. The 4 A's Test had a sensitivity of 85% (95% confidence interval, 73-93) and a specificity of 90% (95% confidence interval, 85-93) compared with the reference standard. The nurse-assessed Confusion Assessment Method had a sensitivity of 23% (95% confidence interval, 13-37) and specificity of 100% (95% confidence interval, 99-100). In phase 2, nurses (n = 51) screened 179 patients for delirium using the 4 A's Test. Compared with the reference rater, the 4 A's Test had a sensitivity of 58% (95% confidence interval, 28-85) and specificity of 94% (95% confidence interval, 85-98). Postimplementation, 64% of nurses thought that the 4 A's Test improved their confidence in delirium detection, and 76% of nurses would consider routine 4 A's Test use.

CONCLUSIONS

The 4 A's Test demonstrated moderate sensitivity and high specificity to detect delirium in a real-world setting after cardiac surgery on the postoperative ward. A modified model of use with less frequent administration, along with increased engagement of the postoperative team, is recommended to improve early delirium detection on the cardiac surgery postoperative ward.

Delirium and depression in cardiac surgery: A comprehensive review of risk factors, pathophysiology, and management

BACKGROUND

Mental health and wellbeing continue to gain more attention as they are inextricably associated with clinical outcomes, particularly quality of life. Many medical ailments and major surgeries affect patients' mental health, including depression and delirium.

AIMS

The objective of this manuscript was to comprehensively review and critically examine the literature pertaining to cardiac surgery, depression, and delirium.

METHODS

This is a narrative review article. We performed our search analysis by using the following key words: "Cardiac Surgery", "Depression", "Delirium", "Clinical outcomes", and "Mental Health". Search analysis was done on MedLine PubMed, accessing indexed peer-reviewed publications.

RESULTS

Cardiac Surgery is a life-altering intervention indicated to improve morbidity and mortality in patients with cardiovascular diseases. Psychiatric conditions before and after cardiac surgery worsen patient prognosis and increase mortality rate. Specifically, preoperative depression increases postoperative depression and is associated with impaired functional status, slow physical recovery, and an increased readmission rate.

DISCUSSION

Although the exact pathophysiology between depression and cardiovascular disease (CVD) is unknown, several pathways have been implicated. Unmanaged depression can also lead to other psychological conditions such as delirium. Like depression, the exact association between delirium and CVD is not well understood, but believed to be multifactorial.

CONCLUSION

Herein, we provide a comprehensive review of the links between depression, delirium, and cardiovascular surgery. We critically examine the current data that pertains to the pathophysiology of these debilitating mental health issues in the context of cardiac surgery. Finally, we summarize the various treatment options available for managing depression and delirium in the cardiac surgery patient population.

2-18F-fluoro-2-deoxyglucose positron emission tomography in delirium

Delirium is a common, serious, yet poorly understood syndrome. Growing evidence suggests cerebral metabolism is fundamentally disturbed; however, it has not been investigated using 2-¹⁸F-fluoro-2-deoxyglucose (FDG) positron emission tomography (PET) in delirium. This prospective study thus explored FDG PET patterns of cerebral glucose metabolism in older inpatients with delirium. A particular emphasis was on the posterior cingulate cortex (PCC), a key region for attention, which is a central feature of delirium. Delirium scans were compared with post-delirium scans using visual analysis and semi-quantitative analysis with NeuroQ; 13 participants (8 female, median 84 y) were scanned during delirium, and 6 scanned again after resolution. On visual analysis, cortical hypometabolism was evident in all participants during delirium (13/13), and improved with delirium resolution (6/6). Using NeuroQ, glucose metabolism was higher post-delirium in the whole brain and bilateral PCC compared to during delirium ( p < 0.05). Greater metabolism in both PCCs correlated with better performance on a neuropsychological test of attention, the WAIS-IV Digit Span Test forwards, and with shorter delirium duration. This research found widespread, reversible cortical hypometabolism during delirium and PCC hypometabolism was associated with inattention during delirium.

The Effect of Treatment of Anemia with Blood Transfusion on Delirium: A Systematic Review

OBJECTIVES

Treating the precipitating factors of delirium is the mainstay of the prevention and treatment of delirium. We aim to investigate the role of anemia and blood transfusion within the multicomponent prevention and treatment strategy of delirium.

DESIGN

Systematic review.

SETTING

We included cohort studies or Randomized Controlled Trials (RCTs) that considered blood transfusion as treatment for delirium or risk factor, and had delirium as outcome.

PARTICIPANTS

Hospitalized patients above 55 years old.

MEASUREMENTS

We searched MEDLINE from 1946 through November 2014. Quality assessment and data extraction were performed systematically.

RESULTS

We included 23 studies (n = 29,471). The majority of the studies (n = 22) had a limited quality and for one study quality was uncertain. Two studies evaluated the association between transfusion strategy and postoperative delirium and found no association. Twenty-one studies investigated blood transfusion as a risk factor for delirium. In four of the 21 studies it could be assumed that delirium occurred after transfusion. One of these studies stated that transfusion was a significant risk factor for subsequent delirium (odds ratio (OR) = 3.68, 95% confidence interval (CI) = 1.32-10.94). The other three studies found no association between transfusion and delirium. In the remaining 17 studies, it was not clear whether delirium occurred before or after transfusion, so no conclusion could be drawn on the role of transfusion in delirium development.

CONCLUSION

The majority of the included studies was not suited to answer the research question properly as the time course of the beginning of delirium as to transfusion was lacking. Our review shows that there is no good quality evidence available for blood transfusion to be a risk factor for delirium or to be a preventive or treatment option.

Detection, Prevention, and Management of Delirium in the Critically Ill Cardiac Patient and Patients Who Undergo Cardiac Procedures

Delirium is an acute change in cognitive functioning, characterized by inattention and associated with alterations in awareness and fluctuation in arousal, disorganized thinking, or altered level that preferentially affects older adult patients. In the acutely ill cardiac patient, the incidence of delirium has been reported as high as 73%, depending on the type and sensitivity of delirium assessment. Cardiac patients with delirium experience higher rates of in-hospital and longer-term mortality and are at risk for progressive cognitive impairment, loss of functional independence, and increased hospitalization costs. As such, delirium represents an undesirable outcome in cardiac patients. Care improvements such as identifying risk of delirium at time of admission or in the preoperative setting; training cardiologist, surgeons, anaesthesiologists and nurses to screen for delirium; implementing delirium prevention programs; and developing standardized delirium treatment protocols might reduce the incidence of delirium and its associated morbidity.

Association of pre-operative brain pathology with post-operative delirium in a cohort of non-small cell lung cancer patients undergoing surgical resection

OBJECTIVE

Post-operative delirium is associated with pre-operative cognitive difficulties and diminished functional independence, both of which suggest that brain pathology may be present in affected individuals prior to surgery. Currently, there are few studies that have examined imaging correlates of post-operative delirium. To our knowledge, none have examined the association of delirium with existing structural pathology in pre-operative cancer patients. Here, we present a novel, retrospective strategy to assess pre-operative structural brain pathology and its association with post-operative delirium. Standard of care structural magnetic resonance imaging (MRIs) from a cohort of surgical candidates prior to surgery were analyzed for white matter hyperintensities and cerebral atrophy.

METHODS

We identified 23 non-small cell lung cancer patients with no evidence of metastases in the brain pre-operatively, through retrospective chart review, who met criteria for post-operative delirium within 4 days of surgery. 24 age- and gender-matched control subjects were identified for comparison to the delirium sample. T1 and fluid-attenuated inversion recovery sequences were collected from standard of care pre-operative MRI screening and assessed for white matter pathology and atrophy.

RESULTS

We found significant differences in white matter pathology between groups with the delirium group exhibiting significantly greater white matter pathology than the non-delirium group. Measure of cerebral atrophy demonstrated no significant difference between the delirium and non-delirium group.

CONCLUSIONS

In this preliminary study utilizing standard of care pre-operative brain MRIs for assessment of structural risk factors to delirium, we found white matter pathology to be a significant risk factor in post-operative delirium. Limitations and implications for further investigation are discussed.

The incidence and consequences of mental disturbances in elderly patients post cardiac surgery--a comparison with younger patients

BACKGROUND

Limited data exist about the incidence and consequences of mental confusion following open heart surgery in different age groups. Likewise, little is known about preoperative predictors of mental confusion.

METHODS

Two-hundred consecutive patients, aged > or =75 years (Group 1), and 400 procedure- and gender-matched younger patients (Group 2) who underwent coronary or valvular surgery were included in a prospective study. The relation between postoperative mental confusion, mortality, morbidity, and quality of life was studied.

RESULTS

Mental confusion was present in 11.8% Group 2 and 22.6% Group 1 patients. The incidence was higher after valvular surgery. Preoperative risk factors in Group 1 patients were diabetes mellitus, a history of heart failure, weak carotid pulsations, and repeat surgery. Late mortality, after a median follow-up duration of 31 months, was significantly worse in patients who were confused, which was related to the underlying disease. Recovery of quality of life was clearly diminished in elderly patients with confusion in contrast to younger patients.

CONCLUSION

Postoperative mental confusion has a high incidence in the elderly population and is associated with a diminished quality of life.

Incidence and risk factors of acute postoperative delirium in geriatric neurosurgical patients

OBJECTIVE

Postoperative delirium (POD) is characterized by an acute change in cognitive function and can result in longer hospital stays, higher morbidity rates, and more frequent discharges to long-term care facilities. In this study, we investigated the incidence and risk factors of POD in 224 patients older than 70 years of age, who had undergone a neurosurgical operation in the last two years.

METHODS

Data related to preoperative factors (male gender, >70 years, previous dementia or delirium, alcohol abuse, serum levels of sodium, potassium and glucose, and co morbidities), perioperative factors (type of surgery and anesthesia, and duration of surgery) and postoperative data (length of stay in recovery room, severity of pain and use of opioid analgesics) were retrospectively collected and statistically analyzed.

RESULTS

POD appeared in 48 patients (21.4%) by postoperative day 3. When we excluded 26 patients with previous dementia or delirium, 17 spontaneously recovered by postoperative day 14, while 5 patients recovered by postoperative 2 months with medication, among 22 patients with newly developed POD. The univariate risk factors for POD included previously dementic or delirious patients, abnormal preoperative serum glucose level, pre-existent diabetes, the use of local anesthesia for the operation, longer operation time (>3.2 hr) or recovery room stay (>90 min), and severe pain (VAS>6.8) requiring opioid treatment (p<0.05). Backward regression analysis revealed that previously dementic patients with diabetes, the operation being performed under local anesthesia, and severe postoperative pain treated with opioids were independent risk factors for POD.

CONCLUSION

Our study shows that control of blood glucose levels and management of pain during local anesthesia and in the immediate postoperative period can reduce unexpected POD and help preventing unexpected medicolegal problems and economic burdens.

Pre-operative mild cognitive dysfunction predicts risk for post-operative delirium after elective cardiac surgery

BACKGROUND AND AIMS

To identify pre-operative risk factors for delirium in patients undergoing elective cardiac surgery, using clearly defined diagnostic criteria for delirium, and a thorough clinical assessment.

METHODS

The incidence of post-operative delirium in 107 patients >or=60 years undergoing elective cardiac surgery was calculated. None of the patients included suffered from dementia. Pre-operative cognitive function in all patients was assessed using the Mini Mental State Examination (MMSE) and post-operative delirium was diagnosed using the Confusion Assessment Method (CAM). Post-operative clinical and cognitive assessments were carried out for all patients.

RESULTS

Twenty-five patients (23.4%) developed delirium post-operatively. Clinical parameters, including age, gender, co-morbidities, medications, and peri-operative parameters, were similar in patients with and without post-operative delirium. Patients with pre-operative subjective memory complaints and lower MMSE scores, undergoing valve operation or valve + coronary artery bypass grafting (CABG), exhibited an increased risk of developing post-operative delirium. Additionally, delirious patients had a significant decline in post-operative MMSE score compared with the non-delirious ones.

CONCLUSIONS

The main pre-operative risk factors for post-operative delirium after elective cardiac operations were subjective memory complaints, mild cognitive impairment, and type of cardiac surgery, such as valve procedures. This study suggests that cognitive evaluation should be included in pre-operative assessment.

Delirium in vascular surgery

Delirium is common in many surgical settings. Patients undergoing elective vascular surgery may be at particular risk of developing delirium, and may have modifiable aetiological factors that can be addressed by pre-operative interventions. We decided to review the literature regarding the incidence and aetiology of delirium in elective vascular surgical patients.

METHODS

We searched medical databases, journals and bibliographies to identify relevant studies. We used predetermined quality criteria for appraisal of the quality of incidence and aetiological studies.

RESULTS

Four studies were identified as relevant to the review. The incidence of delirium ranged from 29.1% to 39.2%. The significant aetiological factors identified were age, pre-operative cognitive impairment, depressive symptoms, inter-operative blood transfusion and previous amputation.

CONCLUSIONS

Delirium is common in people undergoing elective vascular surgery. Further research is required to examine the effect on outcome of delirium, and the effect of psychiatric and geriatric medicine interventions in this setting.

Cerebral perfusion changes in older delirious patients using 99mTc HMPAO SPECT

BACKGROUND

Prior studies describe variable cerebral blood flow changes in delirium. This study aims to investigate cerebral blood flow changes in older hospitalized patients with delirium, the population in which most cases of delirium occur.

METHODS

Participants included hospitalized general medical patients aged 65 years and older with documented delirium and no relevant medical conditions or preexisting abnormalities on neuroimaging prospectively studied using 99mTc HMPAO single photon emission computed tomography (SPECT) scans obtained during and after resolution of delirium. Twenty-two patients enrolled in the study, of whom six completed both scans. All participants underwent neuropsychological assessment immediately prior to SPECT scanning. SPECT images were compared across all participants during delirium; for patients completing paired scans, within-patient comparisons were made.

RESULTS

Visual assessment of SPECT scans revealed perfusion abnormalities in frontal (5 participants) or parietal regions (6 participants); scans were normal in 11 participants (50%). Region-of-interest analysis identified reduced blood flow (p <.01) in the left inferior frontal, right temporal, right occipital, and pontine regions. Analysis of paired scans revealed reversible abnormalities in three participants (p <.001), with decreased right parietal perfusion in two participants and increased left parietal perfusion in one participant.

CONCLUSIONS

The results of this study of a small group of general medical patients are suggestive that frontal or parietal cerebral perfusion abnormalities occur in delirium, and these findings need to be confirmed by future, larger studies. These results may help to improve basic understanding of delirium pathophysiology, to identify long-term changes, and to evaluate response to treatment over time.

The role of neuroimaging in elucidating delirium pathophysiology

Understanding of delirium pathogenesis remains limited despite improved diagnosis, and elucidation of risk factors and prognosis. Major advances in neuroimaging offer the possibility of probing the mechanisms and networks involved in delirium and hence improving understanding of this often devastating syndrome. This review describes the current literature of imaging studies in delirium and related conditions, introduces some of the newer capabilities of neuroimaging with magnetic resonance imaging, positron emission tomography, and single photon emission computed tomography, and discusses how these techniques may be applied to the study of delirium. Despite considerable challenges in patient recruitment, study design, intersubject variability, and scanner and contrast agent availability, imaging offers great potential for the identification and clarification of pathogenic mechanisms of delirium and its long-term sequelae.

Pathophysiology of postoperative delirium: Systemic inflammation as a response to surgical trauma causes diffuse microcirculatory impairment

Postoperative delirium represents a serious complication after major surgery. Patients suffer from anxiety, hallucinations and delusions, and have higher postoperative morbidity and mortality. Generally, the role of acetylcholine deficiency in delirium pathophysiology is widely accepted. How this pathologic state evolves in the postoperative period is the topic of this paper. Systemic inflammation as a response to surgical trauma causes diffuse microcirculatory impairment. The most relevant pathologies include leukocyte adhesion to vessel lining, endothelial cell swelling, perivascular oedema, narrowing of capillar diameters, and lowered functional capillary density. These morphological changes lead to a decrease of nutritive perfusion and to longer diffusion distance for oxygen. Because acetylcholine synthesis is especially sensitive to low oxygen tension, symptoms of its deficiency readily develop. Therapeutic tools to modulate excessive inflammation are available, therefore new strategies of delirium treatment should be implemented in clinical praxis, as well as in preventive measures.

Preoperative predictors of delirium after cardiac surgery: a preliminary study

Preoperative risk factors of postoperative delirium were evaluated in 260 patients admitted for open heart surgery. The incidence of delirium was 11.5%. Independent predictors included cognitive impairment, atrial fibrillation, a history of peripheral vascular disease major depression and advanced age. Aforementioned factors might be helpful in predicting delirium following cardiac surgery.

The role of oxidative stress in postoperative delirium

AIM

This study aimed to determine a marker that predicts delirium using preoperative oxidative processes in patients undergoing cardiopulmonary bypass surgery.

METHOD

Twelve of the 50 patients included in the study showed signs of delirium during postoperative follow-up. The Delirium Rating Scale was used in patients with delirium according to DSM-IV-TR in the postoperative period. Venous blood samples were obtained from the patients the day before and the day after the surgery to determine plasma antioxidant enzyme levels.

RESULTS

While there were no differences in preoperative superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and malondialdehyde (MDA) levels in both groups, catalase (CAT) levels were significantly lower in the delirium group. Postoperative SOD and MDA levels were also higher in the delirium group, while the GSH-Px levels were found to be lower when compared with those during the preoperative period. In the nondelirium group, the postoperative MDA and GSH-Px levels were found to be lower than preoperative levels, and postoperative SOD levels were found to be higher than preoperative levels. CAT levels were lower in the delirium group when the pre- and postoperative levels were compared in both groups. The postoperative levels of SOD, GSH-Px and CAT in the nondelirium group and MDA in the delirium group were significantly higher than preoperative levels.

CONCLUSION

Patients with low preoperative CAT levels appeared to be more susceptible to delirium than patients with higher CAT levels.

Cognitive function after anaesthesia in the elderly

Despite advances in peri operative care, a significant percentage of elderly patients experience transient post operative delirium and/or long-term post-operative cognitive dysfunction (POCD). This chapter reviews the aetiology, clinical features, preventive strategies and treatment of these syndromes. Pre-operative, intra-operative, and post-operative risk factors for delirium and POCD following cardiac and non-cardiac surgery are discussed. It is most likely that the aetiology of delirium and POCD is multifactorial and may include factors such as age, decreased pre-operative cognitive function, general health status and, possibly, intra-operative events. Currently there is no single therapy that can be recommended for treating post-operative cognitive deterioration. Primary prevention of delirium and POCD is probably the most effective treatment strategy. Several large clinical trials show the effectiveness of multicomponent intervention protocols that are designed to target well-documented risk factors in order to reduce the incidence of post-operative delirium and, possibly, POCD in the elderly.

Regional cerebral blood flow in delirium patients

The purpose of the present paper was to determine the possible mechanism of delirium by using xenon-enhanced computed tomography to measure the regional cerebral blood flow (rCBF) of the patients both during delirium and after improvement from delirium. The rCBF measurements of the frontal, temporal and occipital cortex during delirium ranged from 31.4 to 39.6 mL/100 g per min; the rCBF of the thalamus and basal ganglia ranged from 47.5 to 52.4 mL/100 g per min. After recovery from delirium the rCBF of both areas returned to normal. The findings that reduced rCBF during delirium becomes normal once delirium improves suggest that a possible cause of delirium may be the cerebral hypoperfusion.

Delirium after coronary bypass surgery evaluated by the organic brain syndrome protocol

OBJECTIVE

The aim was to evaluate symptoms of delirium from a psychogeriatric perspective occurring postoperative to coronary bypass surgery.

DESIGN

Patients, > or = 60 years, scheduled for coronary bypass surgery (n = 52) were enrolled in a prospective descriptive study. The patients were evaluated before and several times after surgery by the Organic Brain Syndrome scale, and delirium was diagnosed according to psychiatric codes.

RESULTS

Of the 52 patients, 23% presented delirium. These patients were older than the control group, 73.5 +/- 4.2 and 69.3 +/- 5.9 years, respectively (mean +/- SD, p < 0.01), and had more frequently a history of previous stroke (p < 0.05). Emotional delirium was seen in 83%, hyperactive delirium in about 40%, and 25% were classified to have a psychotic delirium. A major finding was a 58% frequency of hallucinations and illusions among patients with delirium, and a similar rate among those without delirium.

CONCLUSION

Delirium is common after cardiac surgery in particular in older patients, but is often under-diagnosed. Hallucinations were common in both delirious and non-delirious patients.

Transient advanced mental impairment: an underappreciated morbidity after aortic surgery

OBJECTIVES

To determine the incidence, risk factors, and associated morbidity of transient advanced mental impairment (TAMI) after aortic surgery.

METHODS

We retrospectively studied the charts of 188 consecutive patients undergoing elective aortic reconstruction during a recent 6-year period at a university hospital. All patients were lucid on admission and nonintubated at the time of evaluation at least 2 days after operation. TAMI was defined as disorientation or confusion on 2 or more postoperative days. Preoperative, intraoperative, and postoperative clinical variables were examined statistically for associations with TAMI.

RESULTS

Fifty-three patients (28%) had development of TAMI 3.9 plus minus 2.8 days after operation. Stepwise logistic regression analysis selected the following independent predictors for TAMI: age >65 years (odds ratio [OR], 7.9; 95% confidence interval [CI], 2.7 to 23.7), American Society of Anesthesiology physical status classification >3 (OR, 2.8; 95% CI, 1.3 to 5.9), diabetes mellitus (OR, 3.4; 95% CI, 1.2 to 9.8), old myocardial infarction (OR, 2.4; 95% CI, 1.1 to 5.3), and hypertension (OR, 2.3; 95% CI, 1.0 to 5.3). Alcohol consumption was not significantly associated with TAMI. In the postoperative period, patients with TAMI were more likely to have hypoxia (P <.001), a need for reintubation (P <.001), pneumonia (P <.001), congestive heart failure (P =.003), and kidney failure (P =.05). In addition, patients with TAMI had a longer duration of endotracheal intubation (3.7 plus minus 7.8 vs 0.6 plus minus 1.2 days, P <.001), stay in the intensive care unit (8.9 plus minus 9 vs 3.9 plus minus 2 days, P <.001), and postoperative hospital stay (14.8 plus minus 11 vs 9.2 plus minus 5 days, P <.001) than patients without TAMI. Twenty (38%) patients with TAMI were discharged to intermediate-care facilities, compared with 11 (8%) patients without TAMI (P <.001). Postoperative variables conferring the largest relative risks for development of TAMI included oxygen saturation less than 92% (5.4), the need for reintubation (3.3), congestive heart failure (3.3), and pneumonia (3.2). TAMI, conversely, conferred the largest relative risks for development of postoperative congestive heart failure (15.3), the need for reintubation (9.3), pneumonia (7.1), and the need for ICU readmission (3.8).

CONCLUSIONS

These data show that TAMI is prevalent among patients undergoing aortic reconstruction and is associated with dramatically increased morbidity and postoperative hospitalization rates.

Functional evaluations for pulmonary resection for lung cancer in octogenarians. Investigation from postoperative complications

We have reviewed the records of our twenty-four patients aged 80 years or older who underwent lung resections for bronchogenic carcinoma between 1983 and 1997 in our department. Eighteen patients were male and six were female. Adenocarcinoma was the histology in more than half of the cases (13 patients), along with 8 squamous cell carcinoma, 2 large cell carcinoma, and one small cell lung carcinoma. More than single lobectomy was performed in each patient. Unilateral pulmonary occlusion tests were employed in patients with impairment in pulmonary functions. Every patient, who underwent the unilateral pulmonary occlusion test, was certified that the total pulmonary vascular resistance index during unilateral pulmonary arterial occlusion test was less than 700 dyne.sec.cm-5.m2. Postoperative cardiovascular complications, such as paroxysmal atrial tachycardia, premature atrial contraction, premature ventricular contraction or atrial fibrillation, were seen in 10 patients. Postoperative respiratory complications, namely, sputa retention, retained secretions or atelectasis, were seen in 7 patients. The extent of dissection of mediastinal lymph node was not correlated to the postoperative pulmonary complications. However, the incidence of arrhythmias in the patients who received R2 mediastinal lymphnode dissection was much higher than in those who received R1 or R0 dissection. Complete blood counts and serum biochemical analysis performed at about three weeks after operations revealed leukocytosis and increases in levels of serum transaminase. These phenomena in leukocytosis and increases in the levels of serum transaminase in these patients were similar to those in younger patients. There was no operative death. We conclude that some patients over 80 years are candidates for lung resection after careful preoperative cardiopulmonary evaluation.