Clinical review: Critical illness polyneuropathy and myopathy

Critical illness polyneuropathy (CIP) and myopathy (CIM) are major complications of severe critical illness and its management. CIP/CIM prolongs weaning from mechanical ventilation and physical rehabilitation since both limb and respiratory muscles can be affected. Among many risk factors implicated, sepsis, systemic inflammatory response syndrome, and multiple organ failure appear to play a crucial role in CIP/CIM. This review focuses on epidemiology, diagnostic challenges, the current understanding of pathophysiology, risk factors, important clinical consequences, and potential interventions to reduce the incidence of CIP/CIM. CIP/CIM is associated with increased hospital and intensive care unit (ICU) stays and increased mortality rates. Recently, it was shown in a single centre that intensive insulin therapy significantly reduced the electrophysiological incidence of CIP/CIM and the need for prolonged mechanical ventilation in patients in a medical or surgical ICU for at least 1 week. The electrophysiological diagnosis was limited by the fact that muscle membrane inexcitability was not detected. These results have yet to be confirmed in a larger patient population. One of the main risks of this therapy is hypoglycemia. Also, conflicting evidence concerning the neuromuscular effects of corticosteroids exists. A systematic review of the available literature on the optimal approach for preventing CIP/CIM seems warranted

Functional recovery of diaphragm paralysis: A long-term follow-up study

SummaryBackgroundLong-term functional outcome of diaphragm paralysis is largely unknown.MethodsA retrospective study was conducted in 23 consecutive patients (21 males, 56±9 years) with uni- or bilateral diaphragm paralysis to examine whether functional respiratory recovery can be predicted from the compound motor action potential (CMAP) of the diaphragm at the time of diagnosis. Pulmonary function and CMAP were evaluated at baseline and at follow-up. CMAP amplitude and latency were recorded by surface electromyography with percutaneous electrical stimulation of the phrenic nerve. Patients were followed for (median) 15 months up to 131 months (range 5–131). Functional respiratory recovery was defined as an increase in forced vital capacity >400ml.ResultsFunctional recovery occurred in 43% of the patients after 12 months (10 out of 23) and in 52% after 24 months (12 out of 23). Type and etiology of paralysis did not influence recovery. CMAP, anthropometric characteristics and baseline pulmonary function did not predict functional respiratory recovery. Whether respiratory muscle training improved pulmonary function is uncertain. Moreover, it did not result in a greater percentage functional respiratory recovery. Relapse after an initial improvement was observed in 26% of the patients.ConclusionsThe present study indicates that functional recovery of diaphragm paralysis is difficult to predict and may occur years after the onset of the paralysis

Intensive insulin therapy in mixed medical/surgical intensive care units.Benefit vs. harm

Intensywne leczenie insuliną (IIT) poprawia rokowanie u pacjentów w stanie krytycznym długotrwale leczonych na oddziale intensywnej terapii (ICU), natomiast dotychczas nie określono potencjalnych zagrożeń i optymalnego stężenia glikemii. Aby wyjaśnić te wątpliwości, wykorzystano odpowiednią populację dwóch randomizowanych, kontrolowanych badań klinicznych. Niezależnie od ilości glukozy podawanej drogą parenteralną, IIT zmniejszało śmiertelność z 23,6% do 20,4% w grupie intention to treat (n = 2748; p = 0,04) oraz z 37,9% do 30,1% w grupie pacjentów leczonych długotrwale (n = 1389; p = 0,002); nie stwierdzono natomiast istotnej statystycznie różnicy wśród osób leczonych krótkotrwale (8,9% vs. 10,4%; n = 1359; p = 0,4). W porównaniu z glikemią 110-150 mg/dl śmiertelność była znacznie wyższa przy glikemii powyżej 150 mg/dl [wskaźnik ryzyka: 1,38% (95% CI: 1,10-1,75); p = 0,007] i niższa przy glikemii poniżej 110 mg/dl [0,77 (0,61-0,96); p = 0,02]. Jedynie u chorych na cukrzycę (n = 407) nie wykazano poprawy śmiertelności po IIT. Zapobieganie uszkodzeniu nerek i polineuropatia stanów krytycznych stwarzają konieczność utrzymywania stężenia glukozy w ciągu dnia ściśle poniżej 110 mg/dl, co z kolei wiąże się z najwyższym ryzykiem hipoglikemii. W okresie 24 godzin po hipoglikemii zmarło 3 pacjentów leczonych konwencjonalnie i 1 leczony intensywną insulinoterapią (p = 0,0004), bez różnicy w ogólnej śmiertelności szpitalnej. U pacjentów wypisanych z oddziału intensywnej terapii, u których obserwowano hipoglikemię, nie występowały nowe problemy neurologiczne. Stwierdzono, że IIT zmniejsza śmiertelność u wszystkich pacjentów na oddziałach intensywnej terapii zarówno chirurgicznych, jak i internistycznych, z wyjątkiem chorych na cukrzycę, nie powodując istotnych zagrożeń. Docelowe wartości glikemii poniżej 110 mg/dl okazały się najbardziej korzystne w odniesieniu do śmiertelności, ale wiązały się również z największym ryzykiem hipoglikemii.Intensive insulin therapy (IIT) improves the outcome of prolonged critically ill patients, but concerns remain regarding potential harm and the optimal blood glucose level. These questions were addressed using the pooled dataset of two randomized controlled trials. Independent of parenteral glucose load, IIT reduced mortality from 23.6% to 20.4% in the intention-to-treat group (n = 2,748; p = 0.04) and from 37.9% to 30.1% among long stayers (n = = 1.389; p = 0.002), with no difference among short stayers (8.9% vs. 10.4%; n = 1,359; p = 0.4). Compared with blood glucose of 110&#8211;150 mg/dl, mortality was higher with blood glucose > 150 mg/dl [odds ratio 1.38 (95% CI 1.10-1.75); p = 0.007] and lower with < 110 mg/dl [0.77 (0.61-0.96); p = 0.02]. Only patients with diabetes (n = 407) showed no survival benefit of IIT. Prevention of kidney injury and critical illness polyneuropathy required blood glucose strictly < 110 mg/day, but this level carried the highest risk of hypoglycemia. Within 24 h of hypoglycemia, three patients in the conventional and one in the IIT group died (p = 0.0004) without difference in hospital mortality. No new neurological problems occurred in survivors who experienced hypoglycemia in intensive care units (ICUs). We conclude that IIT reduces mortality of all medical/surgical ICU patients, except those with a prior history of diabetes, and does not cause harm. A blood glucose target < 110 mg/day was most effective but also carried the highest risk of hypoglycemia

The Presence of Fowler's Syndrome Predicts Successful Long-Term Outcome of Sacral Nerve Stimulation in Women with Urinary Retention

OBJECTIVES: Sacral nerve stimulation (SNS) is an effective treatment for women with urinary retention. Some women present specific electromyography abnormalities of the external urethral sphincter (Fowler's syndrome). The aim of this study was to evaluate whether Fowler's syndrome and psychologic preimplant screening could be predictive factors for long-term success of SNS in women with urinary retention. METHODS: All patients underwent electrophysiologic and urodynamic studies and voiding charts. A validated psychologic screening questionnaire was used. Women with successful temporary stimulation, received a definitive implant (Interstim Medtronic). They were followed prospectively every 6 months. Failure was defined as recurrent retention needing intermittent or permanent catheterisation. RESULTS: Sixty-two women were implanted, 30 with Fowler's syndrome, 32 with idiopathic retention. In those with Fowler's syndrome, 26.6% screened positive for somatisation, as did 43.8% in the idiopathic group (not significant [ns]). Screening for depression was positive in 30% and 18.8%, respectively (ns). There was no correlation with outcome. Twenty-eight patients failed: 9 with Fowler's syndromes, 19 without (p=0.04). Kaplan-Meier analysis showed that patients with Fowler's syndrome benefitted significantly longer from SNS (log-rank test, p=0.005). CONCLUSIONS: The presence of Fowler's syndrome is a positive predictive factor for SNS in female urinary retention. Idiopathic urinary retention patients can benefit as well, but the success might be less predictable. Preimplant psychologic screening, using the Patient Health Questionnaire, does not correlate with long-term outcome of SNS in this population.status: publishe

Inflammatory Neuropathy of the Lumbosacral Plexus following Periacetabular Osteotomy

Introduction. During periacetabular osteotomy (PAO), the sciatic, femoral, and obturator nerves are at risk. Most frequently nerve lesions can be attributed to a mechanical cause; however, in the absence of a clear mechanical cause surgeons are faced with a diagnostic problem and in many cases no diagnosis will be established. We report a case of inflammatory neuropathy of the lumbosacral plexus following a PAO. Case Presentation. A 31-year-old female developed weakness of ankle and knee flexion and extension 6 months after a PAO. Electrophysiological studies revealed damage to the obturator, femoral, and sciatic nerve consistent with an inflammatory lumbosacral plexopathy. MRI of the lumbosacral plexus was normal. The patient was treated with multimodal pain therapy and prolonged physiotherapy; nevertheless, symptoms worsened over time. At 2-year follow-up, there were no signs of recovery. Discussion. Inflammatory neuropathy of the lumbosacral plexus is a potential cause of pain and weakness after ipsilateral orthopaedic procedures. It should be distinguished from more frequently encountered mechanical causes of postsurgical neuropathy based on clinical suspicion, electrophysiological studies, MRI, and nerve biopsy. It is important that the orthopaedic community is aware of this complication since there is some evidence that early recognition and initiation of immunosuppressive therapy can lead to improved clinical outcome

EMG IN SYMPTOMATIC LUMBOSACRAL TARLOV CYST PATIENTS WITH UNEXPLAINED CHRONIC COMPLEX PERINEAL, PELVIC AND/OR SACROISCHIALGIC PAIN SYNDROMES

Introduction Tarlov cysts (TC) are usually considered asymptomatic and therefore overlooked as a possible cause of sacral and sciatic pain, urogenital and bowel problems. This is especially true for smaller cysts. Controversy remains regarding their clinical importance. Because of this underdiagnosed condition, patients often suffer for several years from unrecognized chronic neuropathic pain and neurological disorders. Purpose To report on the presence of lumbosacral TC cysts in unexplained complex chronic pain syndromes (CCPS) and to document the TC as the cause of nerve damage in these patients, using EMG of the lumbosacral myotomes. Methods In an outpatient clinic of physical medicine, for patients consulting for musculoskeletal disorders, 17 patients with longstanding unexplained and intractable CCPS of the perineum, pelvis, sacrum, coccyx, lower back and/or the legs were found to harbor Tarlov cysts on MRI. Other causes of chronic pain were ruled out. EMG of the lumbosacral myotomes was performed by an expert senior neurophysiologist in order to document nerve damage in these patients, including L5, S1, and S2 (tibial nerve innervated intrinsic foot muscles) and S3S4 (external anal sphincter). Results All of the patients harbored more than one TC. Nerve conduction studies showed sural nerve abnormalities in 33.3%, delayed S1 Hoffmann-reflex latencies in 12% and ano-anal reflex abnormalities in 60%. Needle EMG showed neurogenic abnormalities in myotomes L5 (87.5%), S1 (18.8%), S2 (64.3%) and S3S4 (81.3%). All patients had abnormalities in the S2 or S3,S4 myotomes, or in both. Discussion and conclusion In patients with CCPS, the presence of TC should be taken into consideration. A needle-EMG of both the tibial nerve innervated intrinsic foot muscles and the external anal sphincter was able to document sacral nerve root damage in all of these patients. EMG for pelvic, perineal or radicular pain should include a needle EMG of these myotomes.status: publishe

Interventions for preventing critical illness polyneuropathy and critical illness myopathy

BACKGROUND: Critical illness polyneuro-and/or myopathy (CIP/CIM) is an important and frequent complication in the intensive care unit (ICU), causing delayed weaning from mechanical ventilation. It may increase ICU stay and mortality. OBJECTIVES: To examine the ability of any intervention to prevent the occurrence of CIP/CIM. SEARCH STRATEGY: We searched the Cochrane Neuromuscular Disease Group Trials Register (October 2007), MEDLINE (January 1950 to April 2008), EMBASE (January 1980 to October 2007), checked bibliographies and contacted trial authors and experts in the field. SELECTION CRITERIA: All randomised controlled trials (RCTs), examining the effect of any intervention on the incidence of CIP/CIM in adult medical or surgical ICU patients. The primary outcome measure was the incidence of CIP/CIM after at least seven days in ICU, based on electrophysiological or clinical examination. DATA COLLECTION AND ANALYSIS: Two authors independently extracted the data. MAIN RESULTS: Three out of nine identified trials, provided data on our primary outcome measure. Two trials examined the effects of intensive insulin therapy versus conventional insulin therapy. Eight hundred and twenty-five out of 2748 patients randomised, were included in the analysis. The incidence of CIP/CIM was significantly reduced with intensive insulin therapy in the population screened for CIP/CIM (relative risk (RR) 0.65, 95% confidence interval (CI) 0.55 to 0.78) and in the total population randomised (RR 0.60, 95% CI 0.49 to 0.74). Duration of mechanical ventilation, duration of ICU stay and 180-day mortality but not 30-day mortality, were significantly reduced with intensive insulin therapy, in both the total and the screened population. Intensive insulin therapy significantly increased hypoglycaemic events and recurrent hypoglycaemia. Death within 24 hours of the hypoglycaemic event was not different between groups. The third trial examined the effects of corticosteroids versus placebo in 180 patients with prolonged acute respiratory distress syndrome. No significant effect of corticosteroids on CIP/CIM was found (RR 1.09, 95% CI 0.53 to 2.26). No effect on 180-day mortality, new serious infections and glycaemia at day seven was found. A trend towards fewer episodes of pneumonia and reduction of new events of shock was shown. AUTHORS' CONCLUSIONS: Substantial evidence shows that intensive insulin therapy reduces the incidence of CIP/CIM, the duration of mechanical ventilation, duration of ICU stay and 180-day mortality. There was a significant associated increase in hypoglycaemia. Further research needs to identify the clinical impact of this and strategies need to be developed to reduce the risk of hypoglycaemia. Limited evidence shows no significant effect of corticosteroids on the incidence of CIP/CIM, or on any of the other secondary outcome measures, except for a significant reduction of new episodes of shock. Strict diagnostic criteria for the purpose of research should be defined. Other interventions should be investigated in randomised controlled trials.status: publishe

Electromyographic Abnormalities Associated with Symptomatic Sacral Tarlov Cysts

Tarlov, or perineural cysts (TC) are commonly overlooked as a cause of sacroischialgia and urogenital and bowel problems. TC can be seen on MRI, but are often considered asymptomatic. This is especially true for smaller cysts. Moreover, there are only few diagnostic characteristics that can be used to confirm that the cysts are the cause of the symptoms. As a consequence, a lot of controversy remains regarding the clinical importance of TC. Because of this underdiagnosed condition, patients often suffer for several years from unrecognized chronic neuropathic pain and neurological conditions. In this paper, case reports of three patients with giant and smaller symptomatic sacral cysts are presented, in which electromyographic testing was performed in order to demonstrate nerve damage. We conclude that electromyography of the sacral nerve roots can be a reasonable tool for the diagnosis of symptomatic TC, as well as for the differentiation from other pathological entities causing sacroischialgia. Moreover, using electromyography it was also documented that smaller cysts of less than 1 cm can cause nerve damage. Therefore incidence of symptomatic TC may be higher than initially thought.status: publishe

EMG IN SYMPTOMATIC LUMBOSACRAL TARLOV CYST PATIENTS WITH UNEXPLAINED CHRONIC COMPLEX PERINEAL, PELVIC AND/OR SACROISCHIALGIC PAIN SYNDROMES

Tarlov cysts (TC) are usually considered asymptomatic and therefore overlooked as a possible cause of sacral and sciatic pain, urogenital and bowel problems. This is especially true for smaller cysts. Controversy remains regarding their clinical importance. Because of this underdiagnosed condition, patients often suffer for several years from unrecognized chronic neuropathic pain and neurological disorders. Purpose To report on the presence of lumbosacral TC cysts in unexplained complex chronic pain syndromes (CCPS) and to document the TC as the cause of nerve damage in these patients, using EMG of the lumbosacral myotomes. Methods In an outpatient clinic of physical medicine, for patients consulting for musculoskeletal disorders, 17 patients with longstanding unexplained and intractable CCPS of the perineum, pelvis, sacrum, coccyx, lower back and/or the legs were found to harbor Tarlov cysts on MRI. Other causes of chronic pain were ruled out. EMG of the lumbosacral myotomes was performed by an expert senior neurophysiologist in order to document nerve damage in these patients, including L5, S1, and S2 (tibial nerve innervated intrinsic foot muscles) and S3S4 (external anal sphincter). Results All of the patients harbored more than one TC. Nerve conduction studies showed sural nerve abnormalities in 33.3%, delayed S1 Hoffmann-reflex latencies in 12% and ano-anal reflex abnormalities in 60%. Needle EMG showed neurogenic abnormalities in myotomes L5 (87.5%), S1 (18.8%), S2 (64.3%) and S3S4 (81.3%). All patients had abnormalities in the S2 or S3,S4 myotomes, or in both. Discussion and conclusion In patients with CCPS, the presence of TC should be taken into consideration. A needle-EMG of both the tibial nerve innervated intrinsic foot muscles and the external anal sphincter was able to document sacral nerve root damage in all of these patients. EMG for pelvic, perineal or radicular pain should include a needle EMG of these myotomes.status: publishe

Interventions for preventing critical illness polyneuropathy and critical illness myopathy

Critical illness polyneuropathy or myopathy (CIP/CIM) is a frequent complication in the intensive care unit (ICU) and is associated with prolonged mechanical ventilation, longer ICU stay and increased mortality. This is an interim update of a review first published in 2009 (Hermans 2009). It has been updated to October 2011, with further potentially eligible studies from a December 2013 search characterised as awaiting assessment.status: publishe