The relationship between prolonged cerebral oxygen desaturation and postoperative outcome in patients undergoing coronary artery bypass grafting

58 patients who underwent on-pump coronary artery bypass graft surgery were evaluated for changes in regional cerebral oxygen saturation (rSO2) measured by near infrared spectroscopy (NIRS). If rSO2 during the operation fell to more than 20% under the baseline, standardized interventions were undertaken to maintain rSO2. Despite those interventions, in some cases we observed inability to maintain rSO2 above this threshold. Therefore we divided patients in two subgroups: 1. without prolonged rSO2 desaturation; 2. with prolonged rSO2 desaturation (area under the curve >150 min% for rSO2<20% of baseline and >50 min% for rSO2<50% of absolute value). The data were analyzed to determine whether there were major differences in outcome of these two groups. 18 out of 58 patients (31%) had prolonged rSO2 desaturation during operation. There was significantly higher number of diabetic patients in group with prolonged rSO2 desaturation (p=0.02). Intraoperative data revealed significantly more blood consumption during cardiopulmonary bypass (p=0.007) and the need for inotropes (p=0.04) in desaturation group. Three patients in prolonged desaturation group and no one in another group had stroke, coma or stupor (p=0.03). Logistic regression analysis revealed diabetes mellitus and age as predictors for prolonged rSO2 desaturation. We concluded that prolonged intraoperative rSO2 desaturation is significantly associated with worse neurological outcome in patients - nonresponders to standardized interventions for prevention of rSO2 desaturation.

Immeasurable levels of serum phosphate--an unidentified cause of respiratory failure in a diabetic patient

We report a case of immeasurable levels of serum phosphate in a patient with juvenile type Diabetes mellitus and diabetic ketoacidosis who developed respiratory failure. A 27-year-old female with juvenile type insulin-dependent Diabetes mellitus was admitted because of suspected acute mediastinitis and respiratory failure, probably, among other responsible factors, caused and complicated by undetectable levels of serum phosphate. The serum phosphate concentration three days after aggressive treatment was only 0.2 mmol/L. Furthermore, a significant improvement in weakness and lethargy was observed. To the best of our knowledge, this is the first described case of immeasurable levels of serum phosphate. In patients with Diabetes mellitus, serum phosphate concentrations should be routinely checked in order to avoid additional complications.

Stairs climbing test with pulse oximetry as predictor of early postoperative complications in functionally impaired patients with lung cancer and elective lung surgery: prospective trial of consecutive series of patients

AIM

To test the predictive value of stairs climbing test for the development of postoperative complications in lung cancer patients with forced expiratory volume in one second (FEV1)<2 L, selected for an elective lung surgery.

METHODS

The prospective study was conducted in 101 consecutive patients with an FEV1<2 L selected for elective lung surgery for lung cancer. Preoperative examination included medical history and physical examination, lung function testing, electrocardiography, laboratory testing, and chest radiography. All patients underwent stairs climbing with pulse oximetry before the operation with the number of steps climbed and the time to complete the test recorded. Oxygen saturation and pulse rate were measured every 20 steps. Data on postoperative complications including oxygen use, prolonged mechanical ventilation, and early postoperative mortality were collected.

RESULTS

Eighty-seven of 101 patients (86%) had at least one postoperative complication. The type of surgery was significantly associated with postoperative complications (25.5% patients with lobectomy had no early postoperative complications), while age, gender, smoking status, postoperative oxygenation, and artificial ventilation were not. There were more postoperative complications in more extensive and serious types of surgery (P<0.001). The stairs climbing test produced a significant decrease in oxygen saturation (-1%) and increase in pulse rate (by 10/min) for every 20 steps climbed. The stairs climbing test was predictive for postoperative complications only in lobectomy group, with the best predictive parameter being the quotient of oxygen saturation after 40 steps and test duration (positive likelihood ratio [LR], 2.4; 95% confidence interval [CI], 1.71-3.38; negative LR, 0.53; 95% CI, 0.38-0.76). In patients with other types of surgery the only significant predictive parameter for incident severe postoperative complications was the number of days on artificial ventilation (P=0.006).

CONCLUSION

Stairs climbing test should be done in routine clinical practice as a standard test for risk assessment and prediction of the development of postoperative complications in lung cancer patients selected for elective surgery (lobectomy). Comparative to spirometry, it detects serious disorders in oxygen transport that are a baseline for a later development of cardiopulmonary postoperative complications and mortality in this subgroup of patients.

Analysis of preincisional and postincisional treatment with alpha2-adrenoreceptor agonist clonidine regarding analgesic consumption and hemodynamic stability in surgical patients

Preemptive analgesia aims to prevent the sensitization of central nervous system, hence the development of pathologic pain after tissular injury. The aim of the study was to assess the effect of preincisional clonidine treatment on analgesic consumption and hemodynamic stability compared to clonidine administered at the end of the operation and control group. Ninety-one patients undergoing elective colorectal surgery were randomly assigned to four groups: peroral clonidine before operation, epidural clonidine before operation, epidural clonidine at the end of operation, and epidural saline before operation as a control group. After the operation, patient-controlled analgesia with epidural morphine was instituted. Analgesic consumption, blood pressure and heart rate were obtained at 1, 2, 6 and 24 h postoperatively, and the cumulative consumption of analgesics was assessed at the end of the study period. Significant differences (p < 0.05) in postoperative systolic blood pressure, with highest hemodynamic stability was observed at 1 h and 6 h in the group of patients administered epidural clonidine before operation. In this group of patients we found significant reduction in analgesic consumption during the study period (p < 0.05), compared to other groups. The cumulative consumption of analgesics assessed at the end of the study period was significantly reduced (p < 0.05) in the group of patients administered epidural clonidine before operation (8.40 +/- 3.74, respectively) as compared with the peroral clonidine before operation (16.79 +/- 5.75, respectively), epidural clonidine at the end of the operation (11.11 +/- 4.24, respectively) and control group of patients (18.00 +/- 6.45, respectively). Preincisional administration of epidural clonidine was associated with a significantly lower analgesic use, lower cumulative analgesic consumption and greater hemodynamic stability, in comparison with other groups.

[Fast track surgery--enhanced multimodal rehabilitation after surgery]

Despite constant improvements in surgical technique and perioperative care which led to significant reductions in mortality and morbidity after general surgery, complication rates after major abdominal surgery still reach 15-40%. The main cause of postoperative complications (not linked to surgical technique itself) is the perioperative stress reaction potentiated by pain, inadequate perioperative fluid management, immobilisation and hypothermia. Multimodal rehabilitation of surgical patients represents the practical application of advances in surgery, anaesthesiology and postoperative rehabilitation with the aim of reducing perioperative stressors and facilitating an early return of the patient to his/her preoperative functional status. Besides discussing various aspects of multimodal rehabilitation, the authors present their own first experiences with its introduction into everyday clinical practice.

Chronic obstructive pulmonary disease and weaning of difficult-to-wean patients from mechanical ventilation: randomized prospective study

AIM

To compare T-tube and pressure support ventilation (PSV) as two methods of mechanical ventilation weaning of patients with chronic obstructive pulmonary disease (COPD) after failed extubation.

METHODS

A prospective randomized trial carried out at the multidisciplinary intensive care unit (ICU) over 2 years included 136 patients with COPD who required mechanical ventilation longer than 24 hours. The patients who could be weaned from mechanical ventilation were randomized to either a T-tube or PSV 2-hour spontaneous breathing trial. The patients in whom 2-hour trial was successful were extubated and excluded from further research. Patients in whom 2-hour trial failed had mechanical ventilation reinstated and underwent the same weaning procedure after 24 hours in case they fulfilled the weaning criteria. The weaning outcome was assessed according to the following parameters: extubation success, mechanical ventilation duration, time spent in ICU, reintubation rate, and mortality rate.

RESULTS

Two-hour trial failed in 31 patients in T-tube and 32 patients in PSV group, of whom 17 and 23, respectively, were successfully extubated (P<0.001, chi(2)test). Mechanical ventilation lasted significantly longer in T-tube than in PSV group (187 hours vs 163 hours, respectively, P<0.001, Mann-Whitney test). Also, patients in T-tube group spent significantly more time in ICU than patients in PVS group (241 hours [interquartile range 211-268] vs 210 hours [211-268], respectively, P<0.001, Mann-Whitney test). Reintubation was required in 8 and 6 patients in T-tube and PVS group, respectively, and death occurred in 4 and 2 patients, respectively, during ICU stay.

CONCLUSION

Patients with COPD who failed the 2-hour spontaneous breathing trial had more favorable outcome when PVS rather than T-tube method was used for weaning from mechanical ventilation.

[Anesthesia and perioperative management of patients with resection for esophageal carcinoma]

The current approach to the anesthetic procedure and postoperative intensive therapy after esophageal resection for esophageal carcinoma, as well as characteristic perioperative pathophysiological events are presented. The contributory factors of severe postsurgical morbidity are considered too. Esophagectomy is an extented procedure which includes laparotomy, thoracotomy and often cervicotomy, and carries a great surgical stress with a huge fluid shift. It is mostly performed in the aged population with a certain co-morbidity: malnutrition, compromized immune status, respiratory and cardiovascular diseases. Standardization of esophageal resection and reconstructive techniques together with the optimal perioperative management significantly reduce operative mortality. Preoperatively, the patients' nutritive, respiratory and cardiac status should be improved. Intraoperatively, beside adequate depth of anesthesia which enables the optimal metabolic response to surgical stress, the invasive hemodynamic monitoring with insertion of pulmonary artery catheter is of great importance. The aim is to ensure adequate tissue perfusion and oxygenation avoiding pulmonary overhydration at the same time. Postoperatively, important role has epidural analgesia, allowing proper breathing and coughing and routine usage of fiberbronchoscopy for clearance of pulmonary secretion. After resection there are several conditions which contribute to cough and swallow disturbances: bilateral vagotomy, the absence of upper and lower esophageal sphincters, transient aperistalsis of the substitute, sometimes a transient vocal cord paresis. All of these make patients prone to regurgitation and aspiration of duodenal and gastric juice. Currently, the pulmonary complications are the leading problems after this procedure, so their prevention and early treatment are the key tasks for the clinicians.

The use of a World Health Organization Transfusion Basic Information Sheet to evaluate transfusion practice in Croatia

BACKGROUND AND OBJECTIVES

To assess the feasibility of using the World Health Organization (WHO) Transfusion Basic Information Sheet as a bedside tool for data collection and assessing transfusion practice.

MATERIALS AND METHODS

A prospective 6-month audit of all transfusion episodes using the tool.

RESULTS

Eight hundred and twenty-two forms were completed, capturing data on 59.7% of transfusion episodes. Completion of data fields was > 80%, except for the clinician's transfusion targets that were documented in only 58.5% of cases. Twenty per cent of patients received single red cell unit transfusions.

CONCLUSIONS

The Basic Information Sheet can be incorporated into bedside clinical practice. We have identified the need to encourage clinicians to determine and document their transfusion targets before prescribing blood components.

Hyperbaric oxygenation combined with streptokinase for treatment of arterial thromboembolism of the lower leg

Thromboembolic occlusion of peripheral arteries is a common problem in patients referred to vascular surgery departments. Standard treatments include catheter aspiration techniques, use of fibrinolytic agents and surgical thrombendarterectomy. Recent reports have described the use of hyperbaric oxygen therapy in patients with limb ischemia, yet their main focus has been on patients with chronic disorders. We present the case of a 74-year-old woman with atrial fibrillation and acute thromboembolic occlusion of the posterior tibial artery. The patient presented with severe pain in the right calf, unresponsive to non-opioid parenteral analgesia and accompanied by coldness, numbness and partial motor palsy of the right foot. After 60 minutes of oxygenation in a hyperbaric chamber with a pressure of 2.2 bar, the pain receded, although without signs of restored blood flow in the occluded artery. After fibrinolytic therapy with streptokinase, patency of the posterior tibial artery was verified by return of palpable pulsations and color Doppler ultrasonography. By combining hyperbaric oxygenation and streptokinase in the treatment of lower-leg arterial thromboembolism we achieved regression of ischemic pain, prolongation of the survival time of tissues compromised by ischemia and resolved the cause of the ischemia. We believe the use of this therapeutic strategy in selected cases of peripheral arterial thromboembolism is justified.

Comparison of pressure support and T-tube weaning from mechanical ventilation: randomized prospective study

AIM

To compare T-tube and pressure support ventilation (PSV) as two methods of weaning patients from mechanical ventilation.

METHODS

A randomized prospective study included 260 patients who received mechanical ventilation for more than 48 h, and who were admitted to the intensive care unit (ICU) at Dr. Josip Bencevic General Hospital in Slavonski Brod, between August 1999 and October 2000. After fulfilling the clinical criteria for weaning, the patients were randomly assigned to a 2-h trial of spontaneous breathing either with a T-tube system (n=110) or PSV of 8 cm H2O (n=150). The patients who fulfilled weaning criteria at the end of the 2-h trial were extubated. If any signs of poor procedure tolerance were observed during the 2-h trial, the mechanical ventilation was reinstituted. In such patients, the same weaning procedure was repeated after 24 h, or when the patient's clinical condition permitted. Two methods of weaning were compared according to the patient's clinical characteristics, objective parameters, and procedure outcome.

RESULTS

Eighty (73%) patients in the T-tube group and 120 (80%) patients in PSV group successfully completed the 2-h trial and were extubated. Thirty patients in the T-tube group and 30 in the PSV group had weaning difficulties. Total length of additional mechanical ventilation and total length of stay at ICU were significantly shorter in patients undergoing PSV weaning (p<0.001 for all, Man-Whitney test). For the patients with weaning difficulties and Acute Physiology and Chronic Health Evaluation (APACHE) II score >20 on admission, PSV was the superior method of weaning according to rate of successful extubation, time of weaning from mechanical ventilation, total time of mechanical ventilation, and length of ICU stay (p<0.001 for all, Man-Whitney test).

CONCLUSION

In patients with weaning difficulties, PSV with 8 cm H(2)O was more successful weaning method than T-tube.

[Comparison between the rubber Carlens tube and the polyvinylchloride Robertshaw tube for endobronchial intubation]

The aims of the study were to compare prospectively two double-lumen endobronchial tubes (DLTs): red rubber Carlens and left polyvinylchloride Robertshaw DLT with regard to difficulties in intubation and complications during one-lung ventilation. Sixty-two adult patients were randomly intubated with Carlens tube (31 patients) or Robertshaw tube (31 patients). Correct placement of DLTs was assessed using clinical signs and in some patients in the Robertshaw group fiberoptic bronchoscope was used. In the group intubated with the Carlens tube there were significantly more difficulties in passing the tube through the larynx (4 out of 31 patients), compared with the Robertshaw group (not a single patient). There was no difference in the number of patients with difficulties in placing the tube in the left main bronchus; however, the nature of the problem was more complex with the Carlens tube. The frequency of all the complications as well as the occurrence of the most common complications--hypoxemia and increased peak airway pressure, was not different between the groups. In both groups hypoxemia was related to the right side of the operation. Fiberoptic bronchoscope was used in 18 out of 31 patients intubated with the Robertshaw tube. Its use was not correlated with decreased incidence of complications compared to intubation in which tube position was assessed by clinical signs only.

Bronchopulmonary sequestration and dextrocardia

Bronchopulmonary sequestration (BPS) is usually a rare congenital anomaly, which is most frequently extralobar or intralobar. The case of a patient with positional congenital anomaly--dextrocardia (situs thoracalis inversus) and intrapulmonary sequestration (IPS) is presented. Clinical and radiological characteristics of EPS and IPS are discussed, and new combinations of congenital anomalies with bronchopulmonary sequestration are described, dextrocardia and intrapulmonary sequestration. The importance of the algorithm of diagnostic examinations is emphasized, from detection of bronchopulmonary sequestration on the chest roentgenogram to establishing a definite diagnosis by means of angiography.

Effect of neuroleptanaesthesia on VA/Q distribution and pulmonary shunt

The authors studied changes in the ventilation-perfusion ratio and pulmonary shunt in the course of pulmonary surgery in relation to their presurgery values. The study was conducted at the Jordanovac University Department for Thoracal Surgery in Zagreb, examining 35 patients in whom, owing to pulmonary carcinoma, thoracotomy and pulmonary resection were performed. Relevant data were obtained concerning hypoxemia, its incidence, and its intensity in the patients examined. The results obtained have shown that in the presurgery period all the patients had an elevation of pulmonary shunt and an increased ratio of ventilation and blood flow, leading to mild hypoxemia. During the operation, the fall of the pulmonary shunt amounted to 8%; it was smaller after the ligature (bronchi, artery, and vein of the respective lung or its part) than at the end of the surgery (P < 0.001), whereas the ventilation-perfusion ratio fell more markedly after ligature (P < 0.001) than at the end of the operation. The authors conclude that, by knowing the ventilation-perfusion ratio and pulmonary shunt in the presurgical period, it is not possible to predict the changes of these parameters in the course of surgery. This is of special importance, because hypoxemia, occurring as a result of changes in the ventilation-perfusion ratio and pulmonary shunt, seriously endangers the patient's fate during surgery.