Bilateral diaphragmatic paralysis following topical cardiac hypothermia

Topical cardiac hypothermia has been shown to be a safe and effective means of providing protection for the ischemic myocardium during aortic cross-clamping. We report herein two cases of postoperative bilateral diaphragmatic paralysis which we believe resulted from hypothermic injury to the phrenic nerves. After open-heart surgery, both patients experienced prolonged weaning from assisted ventilation and severe orthopnea. Return of normal diaphragmatic and phrenic nerve function was demonstrated in one patient ten months after surgery. Failure to correctly interpret the respiratory failure and orthopnea led to confusion and erroneous types of therapy. Awareness of this complication should lead to improved care and postoperative management of patients.     

Recovery after unilateral phrenic injury associated with coronary artery revascularization

Hemidiaphragmatic paralysis occurs in some patients following CAB surgery, possibly related to an intraoperative stretch or cold-induced phrenic injury. To determine the time and extent of recovery of phrenic nerve function, we studied five patients with left phrenic paresis or paralysis after CAB. The FVC, FEV1, Pmax and PEmax pressures, latency of conduction and amplitude of CDAP with phrenic nerve stimulation, and diaphragmatic excursion during fluoroscopy were measured for 12 months after CAB. Left phrenic paralysis was substantiated in four of five patients, and paresis was present in the other patient. Recovery of the left phrenic nerve occurred in all patients, complete in one and partial in four, but was delayed and continued for up to 12 months. We conclude that phrenic nerve recovery is delayed after CAB-associated injury and may be incomplete up to 14 months later, in keeping with rates of regeneration of other peripheral nerves.     

Etiology and prevention of topical cardiac hypothermia-induced phrenic nerve injury and left lower lobe atelectasis during cardiac surgery

Left hemidiaphragm elevation is frequently noted following cardiac surgery employing topical hypothermia. We speculate that contact of the left phrenic nerve with ice causes nerve injury, resulting in left hemidiaphragm paresis or paralysis and left lower lobe atelectasis. Left diaphragm elevation was noted on postoperative chest x-ray examination of 36 of 60 (60 percent) consecutive patients in whom topical cooling of the heart with a cold slush solution was administered prior to use of a cardiac insulation pad (CIP, Shiley Laboratories, Irvine, California). Following the use of the CIP in a similar group of 60 consecutive patients, only five (8 percent) showed evidence of diaphragmatic elevation. The difference in the incidence of diaphragmatic elevation between these two groups is statistically significant (p less than 0.001). A comparison of postoperative left lower lobe atelectasis prior to the use of the CIP was also statistically significant (p less than 0.001). There was no significant difference in the aortic cross-clamp time or the volume of intraaortic cardioplegia used in these two groups. The use of topical cardiac hypothermia has been shown to protect the myocardium. Phrenic nerve injury secondary to the use of ice in this method has been documented. The use of a cold solution without ice chips or slush, or the insertion of a CIP prior to the use of topical cardiac hypothermia (when ice chips or slush are used) decreases the exposure of the phrenic nerve to cold injury and decreases the incidence of paresis of the left diaphragm and resultant atelectasis.     

Phrenic nerve injury during coronary artery bypass

After coronary artery bypass, some patients have diaphragmatic elevation, usually on the left side. To test our hypothesis that this phenomenon is due to phrenic nerve injury resulting from either 1) dissection of the proximal portion of the left internal mammary artery or 2) topical cooling of the heart with icy slush, we performed the following 2-part study. First, we reviewed our hospital records of 99 coronary artery bypass patients, 55 of whom had received left internal mammary artery grafts and 44 of whom had undergone saphenous vein grafting; the results showed no significant difference between the rates of left-sided diaphragmatic paralysis in the 2 groups (47% versus 41%, respectively). Next, we performed a prospective, randomized study in 100 consecutive patients, using a cardiac insulation pad to protect the left phrenic nerve in 58 patients and using no protective pad in 42 patients. At the time of hospital discharge, left-sided diaphragmatic elevation was seen in 6 (10.3%) of the 58 patients in whom insulation had been used and in 19 (45.2%) of the 42 patients whose phrenic nerve had been unprotected (p < 0.001). We conclude that cooling of the left phrenic nerve with icy slush in the pericardial cavity causes left-sided diaphragmatic paralysis and that the frequency of this injury can be reduced if a cardiac insulation pad is placed between the nerve and the icy slush.     

Diaphragmatic paralysis following cervical chiropractic manipulation: case report and review

This case report documents an uncommon cause of bilateral diaphragmatic paralysis resulting from phrenic nerve injury during cervical chiropractic manipulation. Several months after the initial injury, our patient remains short of breath and has difficulty breathing in the supine position. Other causes of diaphragmatic paralysis and phrenic nerve injury are reviewed.     

Diaphragmatic paralysis in young children: A literature review

Diaphragmatic paralysis (DP) is a rare cause of respiratory distress in young children. In the first years of life, the main cause is phrenic nerve injury after cardiothoracic surgery or obstetrical trauma. DP usually presents as respiratory distress. Asymmetrical thorax elevation, difficulty weaning from mechanical ventilation, pulmonary atelectasis, and repeated pulmonary infections are other suggestive signs or complications. DP is usually suspected on chest X‐ray showing abnormal hemidiaphragm elevation. Although fluoroscopy was considered the gold standard for DP confirmation, it has gradually been replaced by ultrasound, which can be done at the bedside. Some electrophysiological tools may be useful for a better characterization of phrenic nerve injury and chance of recovery. The management of DP is mainly based on clinical severity. In mild asymptomatic cases, DP may only require close monitoring. In more severe cases, adequate ventilatory support and/or surgical diaphragmatic plication may be needed. Electrophysiological tools may help clinicians assess the ideal timing for diaphragmatic plication.     

Diaphragmatic dysfunction after open heart surgery: treatment with a rocking bed

Of 1225 patients undergoing open heart surgery over an 18-month period, 13 had diaphragmatic dysfunction due to phrenic nerve injury; 11 of these had internal mammary artery grafting. Nine had diaphragmatic dysfunction on the same side as the internal mammary artery graft side (7 bilateral and 2 unilateral) as determined by fluoroscopy during phrenic nerve stimulation. Although topical cardiac hypothermia has been the prevailing mechanism for diaphragmatic dysfunction due to phrenic nerve injury after open-heart surgery, dissection of the internal mammary artery with electrocautery, traction, or vascular compromise to the phrenic nerve, or a combination, could be additional factors. Rocking bed ventilation was instituted to facilitate passive diaphragmatic movement and airway decannulation and was continued at home until the phrenic nerve or nerves recovered. These patients were followed up clinically and with serial measurements of vital capacity, respiratory muscle strength, phrenic nerve latency, and fluoroscopy to determine recovery rate. Phrenic nerve recovery occurred from 4 to 27 months after surgery. This recovery was heralded by the patients' ability to assume the supine position without dyspnea when use of the rocking bed was discontinued. Unilateral diaphragmatic recovery was sufficient for the restoration of symptom-free supine posture.     

Diaphragmatic paralysis in children: A review of 11 cases

We reviewed 11 pediatric cases of diaphragmatic paralysis related to nonspinal-cord injury which were managed in our Intensive Care Unit over the past 10 years. Three cases were secondary to birth trauma, 7 followed surgical procedures for congenital heart disease, and 1 occurred in association with injuries sustained in a motor vehicle accident. The paralysis was bilateral in 8 children. The diagnosis was initially suspected on clinical grounds because of respiratory distress, impossibility of weaning from the ventilator, and paradoxical abdominal respiratory movements. Confirmatory investigations included chest radiography, which revealed elevation of the affected hemidiaphragm, fluoroscopy and ultrasound, both of which demonstrated diminished diaphragmatic movement. Electromyography exhibited a failure of diaphragmatic response to phrenic nerve stimulation in 8 patients. All patients were mechanically ventilated: tracheostomy was required in 5 patients. Physiotherapy was considered a beneficial adjuvant measure. Diaphragmatic plication was attempted without success in 3 children. Seven children recovered without sequelae: Partial respiratory autonomy was achieved after an average of 2.6 months, complete autonomy after an average of 5.4 months. Two patients developed chronic lung disease; one of them remains unresponsive, and one child died following accidental extubation. We conclude that the diagnosis of diaphragmatic paralysis is predominantly clinical, and that the outcome of patients treated by adequate endotracheal mechanical ventilation is usually favorable. Pediatr Pulmonol. 1994;18:187–193. © 1994 Wiley-Liss, Inc.     

Electrophysiologic evaluation of phrenic nerves in severe respiratory insufficiency requiring mechanical ventilation

Diaphragmatic paralysis in patients with respiratory insufficiency compounds the problems in the management. In the presence of lower lobe atelectasis, pleural effusion, or a patient's poor respiratory effort, fluoroscopic examination is often not a reliable way to diagnose diaphragmatic paralysis. We observed that transcutaneous phrenic nerve stimulation in the neck and recording the diaphragmatic potentials from electrodes placed on the lower part of the chest is a simple, reliable, and noninvasive technique to diagnose diaphragmatic dysfunction at the bedside in critically ill patients. In 14 postoperative patients and one with cervical spinal cord injury with respiratory failure, we found ten patients who showed phrenic nerve dysfunction. Besides diagnostic utility, the electrophysiologic evaluation of phrenic-diaphragmatic function provides critical information needed for therapy.     

Diagnosis of Abnormal Diaphragm Motion after Cardiothoracic Surgery: Ultrasound Performed by a Cardiac Intensivist vs. Fluoroscopy

Objectives. Abnormal diaphragmatic motion secondary to phrenic nerve injury is not uncommon after pediatric cardiothoracic surgery. Fluoroscopy is the most frequent method of diagnosis but it carries risks associated with transportation of critically ill children and exposure to ionizing radiation. Ultrasonography, a reliable diagnostic method in adults, eliminates both concerns. Since most cardiac intensivists are trained in echocardiography, we tested the hypothesis that chest ultrasound performed by a cardiac intensivist is faster than fluoroscopy, and is highly accurate in predicting fluoroscopy results, therefore serving as an equally useful diagnostic test. Design. Prospective study in consecutive pediatric patients with suspected abnormal diaphragmatic motion after cardiothoracic surgery. All patients underwent fluoroscopy and ultrasound study of the diaphragm. Ultrasound was performed by a pediatric cardiac intensivist and a trainee. Kappa statistic was calculated to assess concordance between both ultrasound readings. Sensitivity, specificity, and positive and negative predictive values (PPV and NPV) were calculated to assess accuracy of each ultrasound test in predicting fluoroscopy results. Results. Twenty-five patients with median age 3 months (12 days–11 years) and median weight of 3.8 kg (2.5–29 kg) were included. The ultrasound diagnosis of the cardiac intensivist was perfectly accurate (100% sensitivity, specificity, and PPV and NPV) in predicting fluoroscopy results. The ultrasound performed by the trainee achieved 85.7% sensitivity, 94.4% NPV, and 100% specificity relative to fluoroscopy. The interoperator reliability of chest ultrasound was 0.89 (95% confidence interval 0.69–1). Delay between clinical suspicion and the diagnostic tests was 15 minutes (5 minutes–2.5 hours) for ultrasound and 17 hours (60 minutes–82 hours) for fluoroscopy (P < 0.001). Conclusions. Chest ultrasound performed by cardiac intensivists allows for an early and accurate diagnosis of abnormal diaphragmatic motion, as evidenced by their ability to predict fluoroscopy findings in pediatric cardiothoracic patients. Training in ultrasound-guided assessment of diaphragmatic motion should be reinforced during pediatric cardiac intensive care fellowship.     

An Unusual Case of Cardiac Tamponade Secondary to an Elevated Right Hemidiaphragm

Diaphragmatic eventration in old age is a rare phenomenon. Typically, it is thought to originate as a result of failure of development of the muscles of the diaphragm. Less commonly, it can occur secondary to acquired conditions resulting from spinal cord or phrenic nerve injury and is only detected incidentally when the patient presents with dyspnea, chest infection, or cardiac compression symptoms. Herein, we report a case of right diaphragmatic paralysis in a 58-year-old man with a presentation of marked elevation of the right hemidiaphragm and ascites causing a picture compatible with cardiac tamponade.     

Can lung volumes and capacities be used as an outcome measure for phrenic nerve recovery after cardiac surgeries?

Phrenic nerve is the main nerve drive to the diaphragm and its injury is a well-known complication following cardiac surgeries. It results in diaphragmatic dysfunction with reduction in lung volumes and capacities. This study aimed to evaluate the objectivity of lung volumes and capacities as an outcome measure for the prognosis of phrenic nerve recovery after cardiac surgeries. In this prospective experimental study, patients were recruited from Cardio-Thoracic Surgery Department, Educational-Hospital of College of Medicine, Cairo University. They were 11 patients with right phrenic nerve injury and 14 patients with left injury. On the basis of receiving low-level laser irradiation, they were divided into irradiated group and non-irradiated group. Measures of phrenic nerve latency, lung volumes and capacities were taken pre and post-operative and at 3-months follow up. After 3 months of low-level laser therapy, the irradiated group showed marked improvement in the phrenic nerve recovery. On the other hand, vital capacity and forced expiratory volume in the first second were the only lung capacity and volume that showed improvement consequent with the recovery of right phrenic nerve (P value <0.001 for both). Furthermore, forced vital capacity was the single lung capacity that showed significant statistical improvement in patients with recovered left phrenic nerve injury (P value <0.001). Study concluded that lung volumes and capacities cannot be used as an objective outcome measure for recovery of phrenic nerve injury after cardiac surgeries.     

Interest of Ultrasonographic Assessment of Diaphragmatic Function in Cardiac Rehabilitation Center: A Case Report

Diaphragmatic paresis is a rare but recognized complication of atrial fibrillation ablation.A 59-year-old woman experiencing dyspnea in supine position and for minimal effort was admitted in a cardiac rehabilitation center. One month before, she was referred to a cardiac center to ablation of paroxysmal atrial fibrillation. After the procedure, the patient developed respiratory failure attributed to aspiration pneumonia and requiring mechanical ventilation.At admission in the rehabilitation center, M-mode ultrasonography reported an absence of movement of the right hemidiaphragm during quiet breathing and a paradoxical movement during voluntary sniffing.Chest ultrasonography can be useful to detect diaphragmatic dysfunction in patients suffering from dyspnea, at admission in a cardiac rehabilitation center. Its use should be envisaged more frequently.Diaphragmatic paresis is a rare but recognized complication of atrial fibrillation ablation. In a multicenter study,¹ this complication has been assessed around 0.48% (from 0.37% to 1.6%, in function of the medical institution). The phrenic nerve is injured during the procedure through the vessels or atria wall. Right phrenic nerve can be damaged during right superior pulmonary vein or superior cava vein disconnection. Furthermore, ablation at the left atrial appendage can injured left phrenic nerve. Depending on ablation procedure, nerve dysfunction can be related to electrical current or thermal lesions.² We report a case of right diaphragmatic paralysis after atrial fibrillation ablation. Respiratory troubles were attributed to pneumonia. Diagnosis was performed using chest ultrasonography upon admission to the rehabilitation center. This case has not been published and supported the usefulness of ultrasonography in rehabilitation center.     

Spontaneous recovery of diaphragmatic strength in unilateral diaphragmatic paralysis

The aim of the present study was to evaluate diaphragmatic strength in patients with unilateral diaphragmatic paralysis and to determine whether patients with recent diaphragm paralysis develop lower inspiratory pressure than patients with longstanding diaphragmatic paralysis. Twenty patients (16 men and 4 women, 62+/-12 years) and six control subjects were included (4 men and 2 women, 53+/-15 years) in the study. Esophageal pressure during sharp sniff (Pes,sniff), bilateral cervical phrenic nerve magnetic stimulation (Pes,cms) and unilateral phrenic nerve stimulation (Pes,ums) (in nine patients) were measured. Sixteen patients presented right diaphragmatic paralysis and four, left diaphragmatic paralysis. Pes,sniff was higher in control subjects than in patients with diaphragmatic paralysis (respectively 110+/-22 cmH2O and 82+/-24 cmH2O, P<0.05). There was no difference in Pes,cms between patients with diaphragmatic paralysis and control subjects (14+/-7 cmH2O vs. 16+/-4 cmH2O; ns). Pes,ums after stimulation of the affected phrenic nerve was less than 4 cmH2O, was 8+/-2 cmH2O after stimulation of the intact phrenic nerve and was correlated to Pes,cms (R=0.87, P<0.01). There was a positive correlation between Pes,cms, Pes,ums of the intact hemidiaphragm, Pes,sniff and the time from the onset of symptoms and the diaphragmatic explorations (respectively R=0.86, P<0.0001; R=0.72, P<0.05; R=0.48, P<0.05). In conclusion, diaphragmatic strength after unilateral diaphragmatic paralysis seems to improve with time.     

A case of left diaphragmatic eventration treated by thoracoscopic plication]

A 59-year-old woman was admitted to our hospital because of left diaphragmatic eventration due to a left phrenic nerve injury following surgery for recurrent thyroid cancer. She underwent plication by thoracoscopic surgery followed by marked expansion of the left lung and improvement of pulmonary function and dyspnea on exercise. Thoracoscopic plication for diaphragmatic eventration is a useful minimally invasive surgical technique.     

Phrenic nerve injury in infants and children undergoing cardiac surgery.

Fifty infants and 50 children less than 15 years undergoing palliative or corrective cardiac surgery in the Brompton Hospital between March and October 1988 had direct percutaneous stimulation of the phrenic nerve before and after operation. Ten patients, six under 1 year of age and four over, developed unilateral phrenic nerve injury. In those aged less than 1 year recovery after operation was prolonged because their diaphragmatic palsy made it difficult to wean them from the ventilator. Older children had symptoms but their rate of recovery did not seem to be affected by the phrenic nerve injury. Phrenic nerve damage was no more frequent after a lateral thoracotomy than after a median sternotomy. There was no significant association with the type of operation performed, the experience of the surgeon, the use of bypass or topical ice, the duration of bypass, circulatory arrest or aortic cross clamping, or the age of the patient at the time of operation. In patients who had cardiopulmonary bypass the risk of injury was significantly higher in those who had undergone previous operation. The 10% frequency of phrenic nerve injury determined in this prospective study was higher than that seen in earlier retrospective reports. Direct percutaneous stimulation of the phrenic nerve can be used at the bedside in infants and children to facilitate early and accurate diagnosis of phrenic nerve palsy, and the results may influence early management.     

Phrenic nerve injury in infants and children undergoing cardiac surgery

Fifty infants and 50 children less than 15 years undergoing palliative or corrective cardiac surgery in the Brompton Hospital between March and October 1988 had direct percutaneous stimulation of the phrenic nerve before and after operation. Ten patients, six under 1 year of age and four over, developed unilateral phrenic nerve injury. In those aged less than 1 year recovery after operation was prolonged because their diaphragmatic palsy made it difficult to wean them from the ventilator. Older children had symptoms but their rate of recovery did not seem to be affected by the phrenic nerve injury. Phrenic nerve damage was no more frequent after a lateral thoracotomy than after a median sternotomy. There was no significant association with the type of operation performed, the experience of the surgeon, the use of bypass or topical ice, the duration of bypass, circulatory arrest or aortic cross clamping, or the age of the patient at the time of operation. In patients who had cardiopulmonary bypass the risk of injury was significantly higher in those who had undergone previous operation. The 10% frequency of phrenic nerve injury determined in this prospective study was higher than that seen in earlier retrospective reports. Direct percutaneous stimulation of the phrenic nerve can be used at the bedside in infants and children to facilitate early and accurate diagnosis of phrenic nerve palsy, and the results may influence early management.     

Necrotizing fasciitis involving the chest and abdominal wall caused by Raoultella planticola

Background

Dengue is considered one of the most common mosquito borne illnesses in the world. Although its clinical course is usually uneventful, complications have rarely been known to arise. These include neurological manifestations such as neuropathies.

Case presentation

We report a middle aged patient from urban Sri Lanka who developed diaphragmatic paralysis secondary to phrenic neuropathy a month after recovering from dengue fever. He was managed conservatively and made a full recovery subsequently.

Conclusion

Isolated phrenic nerve palsy causing diaphragmatic paralysis should be considered a recognized complication of Dengue fever. A patient usually gains full recovery with conservative management.     

Atypical presentation of bilateral phrenic nerve palsy and its unusual recovery after coronary artery bypass grafting

Bilateral phrenic nerve paralysis after coronary artery bypass surgery in a 47-year-old female patient is reported. This became evident on the 5th post-extubation day and mimicked acute coronary syndrome and led to difficulty in diagnosis. The patient required re-intubation and mechanical ventilation for only 6 days. The diagnosis of clinical and radiological abnormalities suggestive of bilateral phrenic nerve dysfunction was assisted by fluoroscopy, measurement of needle electromyography, and phrenic nerve motor conduction studies. The patient was followed up postoperatively for 14 weeks with complete regression of the neuropathy one month after surgery. An awareness of this complication should lead to improved care and successful postoperative management of patients.     

Diaphragmatic weakness and paralysis

Diaphragmatic weakness implies a decrease in the strength of the diaphragm. Diaphragmatic paralysis is an extreme form of diaphragmatic weakness. Diaphragmatic paralysis is an uncommon clinical problem while diaphragmatic weakness, although uncommon, is probably frequently unrecognized because appropriate tests to detect its presence are not performed. Weakness of the diaphragm can result from abnormalities at any site along its neuromuscular axis, although it most frequently arises from diseases in the phrenic nerves or from myopathies affecting the diaphragm itself. Presence of diaphragmatic weakness may be suspected from the complaint of dyspnea (particularly on exertion) or orthopnea; the presence of rapid, shallow breathing or, more importantly, paradoxical inward motion of the abdomen during inspiration on physical examination; a restrictive pattern on lung function testing; an elevated hemidiaphragm on chest radiograph; paradoxical upward movement of 1 hemidiaphragm during fluoroscopic imaging; or reductions in maximal static inspiratory pressure. The diagnosis of diaphragmatic weakness is confirmed, however, by a reduction in maximal static transdiaphragmatic pressure (Pdimax). The diagnosis of diaphragmatic paralysis is confirmed by the absence of a compound diaphragm action potential on phrenic nerve stimulation. There are many causes of diaphragmatic weakness and paralysis. In this review we outline an approach we have found useful in attempting to determine a specific cause. Most frequently the cause is either a phrenic neuropathy or diaphragmatic myopathy. Often the neuropathy or myopathy affects other nerves or muscles that can be more easily investigated to determine the specific pathologic basis, and, by association, it is presumed that the diaphragmatic weakness or paralysis is secondary to the same disease process.