Lessons from rhinology and facial plastic surgery clinical negligence claims in England 2013-2018.

OBJECTIVE: This study reviewed all rhinology clinical negligence claims in the National Health Service in England between 2013 and 2018. METHOD: All clinical negligence claims held by National Health Service Resolution relating to rhinology in England between 1 April 2013 and 1 April 2018 were reviewed. RESULTS: There were 171 rhinology related claims with a total estimated potential cost of £13.6 million. There were 119 closed claims (70 per cent) with a total cost of £2.3 million, of which 55 claims resulted in payment of damages. Over three quarters of all rhinology claims were associated with surgery (n = 132). Claims associated with endoscopic sinus surgery had the highest mean cost per claim (£172 978). Unnecessary pain (33.9 per cent) and unnecessary operation (28.1 per cent) were the most commonly cited patient injuries. CONCLUSION: Patient education and consent have been highlighted as key areas for improvement from this review of rhinology related clinical negligence claims. A shift in clinical practice towards shared decision making could reduce litigation in rhinology.

The internal nasal valve: a validated grading system and operative guide.

PURPOSE: Nasal obstruction is a highly subjective and commonly reported symptom. The internal nasal valve (INV) is the rate limiting step to nasal airflow. A static INV grading score was devised with regard to visibility of the middle turbinate. METHODS: A prospective study of all patients who underwent primary external functional septorhinoplasty in 2017 for nasal obstruction. All patients' INV score was assessed pre- and postoperatively in a blinded and independent fashion by surgeons of varying seniority. RESULTS: Twenty-eight patients were studied, with mean age 30.9 years and follow-up 18.8 weeks. Inter-rater and test-retest reliability of INV grading were excellent, with Cronbach's alpha 0.936 and 0.920, respectively. There was also statistically significant improvement in both subjective and objective postoperative outcome measures including nasal inspiratory peak flows. CONCLUSIONS: We demonstrate a novel, easy to interpret, clinically valuable grading system of the static internal nasal valve that is reliable and reproducible.

Peak nasal inspiratory flow correlates with quality of life in functional endoscopic sinus surgery.

OBJECTIVES: Whilst nasal function and airflow improve subjectively following functional endoscopic sinus surgery (FESS), a clinically useful and objective tool for quantifying such improvement is lacking. The peak nasal inspiratory flow (PNIF) metre offers convenient and objective measures of nasal patency. However, it has not yet been established whether changes in PNIF after surgery reflect changes in subjective disease burden. In this study we aimed to determine whether changes in PNIF correlate with commonly used subjective symptom and quality of life outcome measures following FESS for chronic rhinosinusitis (CRS). DESIGN: Prospective cohort. SETTING: Royal National Throat Nose and Ear Hospital. PARTICIPANTS: Thirty-seven patients undergoing FESS for CRS, with or without polyps (21 male, mean age 48.8). MAIN OUTCOME MEASURES: PNIF, "SNOT-22", "NOSE" and "VAS" questionnaires were performed before and after surgery. RESULTS: In all patients, there was a strong negative correlation between change in PNIF and change in "SNOT-22" score following surgery (Pearson r=-.64, P<.0001). Strong negative correlations were also seen during subgroup analysis of patients with and without polyps (r=-.57, P=.006 and r=-.67, P=.005, respectively). Change in PNIF correlated significantly with change in "NOSE" score following surgery in all patients and those without polyps (r=-.54, P=.0005 and r=-.68, P=.003). There were no significant correlations between PNIF and VAS (nasal obstruction). CONCLUSIONS: Changes in PNIF after FESS appear to best reflect improvements in quality of life in CRS as measured using the "SNOT-22" questionnaire.

Outcomes in endoscopic sinus surgery: olfaction, nose scale and quality of life in a prospective cohort study.

OBJECTIVES: To determine the efficacy of endoscopic sinus surgery (ESS) on olfactory function in chronic rhinosinusitis patients with nasal polyps (CRSwNP) and without nasal polyps (CRSsNP) and to compare the nasal obstruction and symptom evaluation (NOSE) scale before and after surgery. DESIGN: A prospective cohort study SETTING: Royal National Throat and Nose and Ear Hospital, London UK. PARTICIPANTS: One hundred and thirteen patients with CRS; 60 CRSwNP and 53 CRSsNP. OUTCOME MEASUREMENTS: Olfaction was measured using both the University of Pennsylvania Smell Investigation Test (UPSIT) and the 'sense of smell' visual analogue scale (VAS). The NOSE scale, the sinonasal outcome test (SNOT 22) and the Lund-Kennedy (LK) surgeon reported scores were also measured pre- and postoperatively at 6 months. RESULTS: The UPSIT psychophysical measurement significantly improved following ESS in the CRSwNP subgroup as did the patients perceived VAS sense of smell. However, in the CRSsNP subgroup, the improved VAS and UPSIT measurements were not significant. The NOSE, SNOT 22 and LK scores all improved significantly. The olfactory improvement as measured by the UPSIT correlated to the SNOT-22, but a correlation between the NOSE score and UPSIT was not found. CONCLUSIONS: Endoscopic sinus surgery significantly improved the patient's perceived and measured sense of smell in the CRSwNP subgroup which is the most surgically responsive CRS subgroup. Additionally, improved olfaction in the CRSwNP subgroup is most likely to improve the patient's quality of life. Endoscopic sinus surgery significantly improved the NOSE scale in both CRS subgroups at 6 months following surgery.

The outcome of septorhinoplasty surgery on olfactory function.

OBJECTIVES: To assess olfactory outcomes in patients undergoing septorhinoplasty surgery in our unit. DESIGN: Prospective cohort study. SETTING: The Royal National Throat Nose and Ear Hospital, London. PARTICIPANTS: Forty-three patients undergoing functional septorhinoplasty (Males = 26; mean age = 34.1 ± 12.2) were recruited into the study. MAIN OUTCOME MEASURES: The primary outcome of olfactory function was assessed using 'Sniffin sticks'. Our secondary outcomes were assessment of patient quality of life using the disease specific Sino-nasal Outcome Test-23 questionnaire (SNOT-23) and a visual analogue scale for sense of smell. These measures were repeated at 12 weeks post operatively. RESULTS: There was a significant change in the Sniffin' sticks score post-operatively (8.3 versus 9.6; P < 0.001). The SNOT-23 score also showed a significant improvement post-operatively (53.5 versus 40.4; P < 0.001). A significant improvement was not found in the smell/taste question (question 21) of the SNOT-23 questionnaire as well as the visual analogue scale for sense of smell. A difference in olfactory outcome was not found between open versus closed approaches, primary versus revision surgery and traumatic versus non traumatic cases. CONCLUSIONS: The results show a measured significant improvement in olfaction following functional Septorhinoplasty but not a subjective improvement in the patients perception of their sense of smell and hence not a clinically significant difference. The reasons for the measured improvement are not clear and are likely to be multifactorial.

The need for an objective measure in septorhinoplasty surgery: are we any closer to finding an answer?

OBJECTIVES: To assess the reliability of nasal inspiratory peak flow (NIPF) in providing a clinically accurate objective measure following functional septorhinoplasty by comparing it to the validated disease-specific quality-of-life questionnaire, SNOT-22. Studies so far have demonstrated poor correlation between bilateral NIPF and symptom-specific nasal questionnaires following septorhinoplasty. DESIGN: To perform a prospective comparative analysis between NIPF and the validated disease-specific quality-of-life questionnaire SNOT-22 and to determine whether a correlation exists following septorhinoplasty surgery. SETTING: The Royal National Throat Nose and Ear Hospital, London. PARTICIPANTS: A total of 122 patients (78 males, 44 females; mean age 33.5 ± 12.2 years) were recruited from the senior authors rhinology clinic and underwent functional septorhinoplasty surgery. MAIN OUTCOME MEASURES: Preoperative and postoperative nasal inspiratory peak flow (NIPF) measurements were performed in addition to the completion of three subjective quality-of-life and symptom assessment tool questionnaires; Sinonasal Outcome Test 22 (SNOT-22), Nasal Obstruction Symptom Evaluation (NOSE) and Visual Analogue Scale (VAS: 0-10). RESULTS: The mean preoperative NIPF was 88.2 L/min, and the postoperative value was 101.6 L/min and showed a significant improvement following surgery (P = 0.0064). The mean total SNOT-22 score improved significantly from 48.6 to 26.6 (P < 0.0001); the NOSE score from 14.1 to 6.6 (P < 0.0001); and the Visual Analogue Scale (VAS) blockage score from 6.9 to 3.2 (P < 0.0001). All individual domains assessed showed improvements postoperatively, but no correlation was found between the NIPF and SNOT-22 score. Equally, we did not find a correlation between NIPF and the symptom-specific NOSE questionnaire and the nasal blockage domain on the Visual Analogue Scale (VAS) scale. CONCLUSION: We have demonstrated that NIPF does not correlate with the SNOT-22 disease-specific questionnaire, although both outcomes significantly improve postoperatively. At present, we are still lacking a clinically accurate objective measure of nasal function for the evaluation of patients undergoing septorhinoplasty surgery.

Variations in paranasal sinus anatomy: implications for the pathophysiology of chronic rhinosinusitis and safety of endoscopic sinus surgery.

OBJECTIVES: To study the radiologic anatomy of the paranasal sinuses in patients with and without chronic rhinosinusitis to assess whether anatomic variations are associated with disease pathology, and to identify those variants that may impact operative safety. SETTING: Tertiary referral otolaryngology unit. MAIN OUTCOME MEASURES: Incidence and nature of anatomic variants with potential impact on operative safety, and the presence or absence of sinus mucosal disease and its correlation with anatomic variants with a potential impact on mucociliary clearance. METHODS: We reviewed 278 computed tomographic scans from patients with rhinosinusitis symptoms to investigate anatomic variations that may predispose to sinusitis or impact on operative safety. The incidence of variants with potential impact on sinus drainage was compared between patients with and without sinus mucosal disease with logistic regression. RESULTS: A closed osteomeatal complex was identified in 148 patients (53%), followed by concha bullosa in 98 patients (35%). Closed osteomeatal complex and nasal polyposis were independent risk factors for sinus mucosal disease. Anatomic variants with a potential impact on operative safety included anterior clinoid process pneumatization (18%), infraorbital ethmoid cell (12%), sphenomaxillary plate (11%), and supraorbital recess (6%). In 92% of patients, the level difference between the roof of the ethmoid cavity and the cribriform plate was Keros I. CONCLUSIONS: Bony anatomic variants do not increase the risk of sinus mucosal disease. However, anatomic variants with a potential impact on operative safety occur frequently and need to be specifically sought as part of preoperative evaluation.

Prophylactic vs postoperative antibiotic use in complex septorhinoplasty surgery: a prospective, randomized, single-blind trial comparing efficacy.

OBJECTIVE: To compare the efficacy of prophylactic vs postoperative antibiotic use in complex septorhinoplasty and strengthen the evidence base for antibiotic use in nasal surgery. DESIGN: A randomized, prospective, single-blinded trial. One hundred sixty-four patients requiring complex septorhinoplasty surgery were recruited sequentially from the waiting lists of the 2 senior authors. Power was calculated at 80% at the 5% significance level. Patients randomized to the prophylactic arm of the study received three 1200-mg intravenous doses of amoxicillin-clavulanate, given at induction of anesthesia and at 6 and 12 hours postoperatively. Patients in the postoperative antibiotic arm received a 7-day course of 375 mg of amoxicillin-clavulanate 3 times a day. Patients allergic to penicillin were given erythromycin. Clinical and microbiological evidence of infection on the 10th postoperative day was categorized as either minor (vestibulitis) or major (nasal or septal cellulitis, septal abscess, secondary hemorrhage, or donor-site infection) infections. RESULTS: At follow-up, 6 (7%) of 82 patients in the prophylactic arm and 9 (11%) of 82 of patients in the postoperative arm showed evidence of infection. Most (80%) of infections were minor. There was no significant difference in infection rates between the prophylactic and postoperative arms on chi2 analysis (P = .42). All 164 patients completed the study on an intention-to-treat basis. CONCLUSION: We recommend the use of prophylactic antibiotics rather than empirical postoperative antibiotics for patients undergoing complex septorhinoplasty.

A prospective randomized controlled trial evaluating alcohol on loudness perception in cochlear implant users.

AIM: The aim of this study was to determine the effects of alcohol on the psychophysical responses in patients with cochlear implants. This has not been previously studied. It was also hoped to provide information that could suggest possible sites of action of the known effects of alcohol on the auditory pathway. DESIGN: A prospective randomized placebo-controlled trial, with full ethical approval. PARTICIPANTS: Eight successful cochlear implant users were selected, of whom two had bilateral implants which were tested separately. In total 10 cochlear implants were tested. INTERVENTION: Alcohol was given in the form of vodka (50% alcohol, 1 mL/kg body weight) with 500 mL of orange and cranberry juice. The placebo control was given in the form of 500 mL of orange and cranberry juice alone. OUTCOME MEASUREMENT: The 'comfort level' (C level) was recorded before, and 1 h after alcohol or placebo ingestion for each patient's cochlear implant. Blood alcohol concentration was determined prior to alcohol or placebo consumption and then repeated after 45, 60, 90 and 180 min. RESULTS: The mean blood alcohol concentration 1 h after ingestion was 50 mg/dL. In the 'alcohol' arm the mean electrical unit increase in the C level was 19.9 with a standard deviation of 2.2. In the control arm the mean change in C level was 0.10 with a standard deviation of 0.3. CONCLUSIONS: In this first prospective randomized control study of the effect of alcohol on sound perception in cochlear implant users, alcohol significantly increased the upper end of the dynamic range (C levels) in comparison with placebo (P = <0.0001 using paired t-test analysis). This effect is likely to be the result of change in the auditory pathways proximal to the cochlea.

Gold weight implants in the management of lagophthalmos in facial palsy.

The otolaryngologist plays an essential role in the diagnosis and management of a facial palsy. We present one of the largest cohort prospective studies in the UK of 22 patients with gold weight implants, including ancillary oculoplastic techniques, and their outcomes. Facial paralysis places the eye at risk and protection and lubrication of the eye is paramount in the management of these patients. If recovery of facial function is likely to be delayed or negligible, gold weight loading of the upper lid has been shown to be effective in providing a dynamic solution to lagophthalmos. Following surgery, complete eye closure was possible in the upright position in 18 patients (82%). Two patients had their weights removed secondary to infection (9%). At long-term follow up, four patients judged their vision to have deteriorated (29%). Two of these, after investigation by the ophthalmologists, were found to have pressure astigmatism and removal corrected the visual problems. Overall patient satisfaction with the procedure is high and all reported improvement in eye closure following the operation. An algorithm for the management of the eye in patients with facial palsy is outlined.

Evaluation of hearing thresholds in 3-month-old children with a cleft palate: the basis for a selective policy for ventilation tube insertion at time of palate repair.

Hearing thresholds in children with a cleft palate prior to cleft palate repair are not widely documented, and audiological criteria for short-term ventilation tube insertion do not exist. The aims of this prospective study are to estimate hearing thresholds in 40 children with a cleft palate by 3-month developmental age with auditory brainstem responses (ABRs) under natural sleep and to estimate a hearing threshold guideline for short-term ventilation tube insertion. Our results show a wide range of air conduction hearing thresholds using click ABRs (2-4 Hz), which ranged from 25 to 102 dBnHL in the left ear and from 25 to 80 dBnHL in the right ear with means of 53 and 49 and standard deviations of 17 and 13 respectively. The bone conduction thresholds ranged from 0 to 55 dBnHL with a mean of 26 and a standard deviation of 13. Eighty-three per cent of children had flat, type B, on high-frequency tympanograms, indicative of middle ear effusion. Thirty per cent of the infants had a cleft palate associated with a known syndrome. Currently, it is the authors' practice to use short-term ventilation tubes on a selective basis at the time of cleft palate repair when there is a conductive hearing loss of more than 55 dBnHL in the better ear as determined by ABR with type B high-frequency tympanograms. This threshold level takes into account electrophysiological and auditory pathway maturation discrepancies. With this as the guideline, between 28% and 35% of the children in this study would be eligible for surgery. This criterion still requires further validation.

Management of lateral cystic swellings of the neck, in the over 40s' age group.

We present a series of three case reports of patients over the age of 40 with cystic swellings in the lateral neck. Clinically they masqueraded as branchial cysts, but subsequently were diagnosed as being squamous cell carcinoma cystic lymph node metastasis arising from an occult tonsillar primary. Currently there is an absence of national guidelines for the treatment of lateral neck cysts in the over 40s' age group that subsequently prove to be cystic metastases from occult tonsillar primaries. This disease process is more common than thought, with up to 80 per cent of so-called branchial cysts in the over 40s' age group being malignant. We recommend that patients over the age of 40 presenting with lateral cystic swellings in the neck should have a high suspicion of malignancy and require a panendoscopy, ipsilateral tonsillectomy and blind biopsies of Waldeyer's ring. This avoids inadvertent excision of a possible cystic lymph node metastasis. If the panendoscopy histology proves to be benign, then proceed to excision of the cyst with frozen section analysis of it. If this confirms it to be benign then that is all that is necessary; if the frozen section is however positive for carcinoma then the surgeon can proceed at that time to a formal neck dissection and therefore avoid a further procedure. In the event of an occult tonsillar malignancy, excision of the cyst as part of a neck dissection with post-operative radiotherapy is recommended. It is our aim to treat a cystic lymph node metastasis as you would a solid lymph node metastasis.

Jugular bulb oxyhemoglobin desaturation, S100beta, and neurologic and cognitive outcomes after coronary artery surgery.

UNLABELLED: We reported that a decline in cognitive performance 3 mo after coronary artery bypass grafting surgery is associated with palpable aortic atheroma, but not postoperative jugular bulb oxyhemoglobin saturation (SjO2) <50%. However, the effect of SjO2 on clinical neurologic findings is not known. S100beta is a possible surrogate biochemical marker of brain injury, and we report here the scored clinical neurologic findings in 98 patients from our previous study in relation to SjO2, cognitive performance, aortic atheroma, and S100beta. Patients underwent a scored neurologic examination and cognitive assessment the day before and 3 mo after coronary artery bypass grafting surgery. Intraoperatively, intermittent blood sampling was performed, and postoperatively, the area under the curve describing SjO2 <50% in relation to time was calculated from continuous jugular bulb reflectance oximetry. Palpation was used to assess the ascending aorta for the presence of atheroma. The jugular bulb concentration of S100beta was measured 6 h after completion of surgery. The neurologic score 3 mo after surgery did not correlate with either intra- or postoperative SjO2 (r = 0.111, P = 0.278; and r = -0.074, P = 0.467, respectively). The main determinant of neurologic score at 3 mo was the preoperative neurologic score (r(2) = 0.63, P < 0.001), whereas palpable atheroma of the ascending aorta made a small but significant contribution (r(2) = 0.034, P = 0.004). Neurologic and cognitive scores correlated before surgery (r = 0.226, P = 0.022) and at 3 mo after surgery (r = 0.348, P < 0.001). A preoperative neurologic deficit of two or more had a small but significant negative effect on cognitive performance at 3 mo (standardized beta = -0.097, P = 0.018). There was a significant univariate correlation between S100beta and the 3-mo neurologic score (r = -0.232, P < 0.05), but not a multivariate correlation (beta = -0.090, P = 0.156). IMPLICATIONS: Intraoperative jugular bulb oxyhemoglobin saturation (SjO2) and postoperative SjO2 <50% do not have an important influence on long-term neurologic outcome after coronary artery bypass graft surgery. Subtle preoperative neurology is associated with long-term cognitive decline, and aortic atheroma is a risk factor for both cognitive and neurologic decline.

Cerebral hypoperfusion in immediate postoperative period following coronary artery bypass grafting, heart valve, and abdominal aortic surgery.

Perioperative levels of jugular bulb oxyhaemoglobin saturation (Sj(O(2))) and lactate concentration (Lj), and postoperative duration of Sj(O(2))<50% were compared between patients undergoing coronary artery bypass grafting (CABG) (n=86), heart valve (n=14) and abdominal aortic (n=16) surgery. Radial artery and jugular bulb blood samples were aspirated after induction of anaesthesia, during re-warming on cardiopulmonary bypass (CPB) (36 degrees C), on arrival in the intensive care unit (ICU) and, subsequently, at 1, 2 and 6 h after ICU admission. Most patients having heart surgery were hypocapnic at 36 degrees C on CPB. Following CABG and heart valve surgery, many patients were hypocapnic whereas after abdominal aortic surgery, most were hypercapnic. During CPB and postoperatively, Sj(O(2)) and Lj were significantly correlated to Pa(CO(2)) and the arterial concentration of lactate (La) respectively (P<0.05). After correction for arterial carbon dioxide tension (Pa(CO(2))) and La, there were no significant changes in Sj(O(2)) or Lj on CPB. Postoperatively, having corrected for Pa(CO(2)), there were significant effects on Sj(O(2)) over all groups as a result of time from surgery (P<0.001) and its interaction with operation type (P<0.001). Following correction for La, there were no postoperative effects on Lj. No significant differences (P=0.2) in duration of Sj(O(2))<50% existed between patients undergoing CABG (1054 (82) min), abdominal aortic (893 (113) min) and heart valve (1073 (91) min) surgery. The lack of significant reciprocal effects on Lj combined with the frequency of hypocapnia and strong influence of Pa(CO(2))()on Sj(O(2)), suggest that Sj(O(2))<50% during CPB and after cardiac surgery represents hypoperfusion as a consequence of hypocapnia rather than cerebral ischaemia.

Cognition after coronary artery surgery is not related to postoperative jugular bulb oxyhemoglobin desaturation.

During the early postoperative period after coronary artery bypass grafting (CABG) surgery, many patients experience jugular bulb oxyhemoglobin desaturation (SjO(2) < 50%). We sought to determine whether SjO(2) during cardiopulmonary bypass and the early postoperative period influenced long-term cognitive performance after CABG surgery. One hundred two patients completed a battery of cognitive tests the day before and 3 mo after CABG surgery. A General Cognitive Score was generated from these tests as an overall measure of cognitive function. Intraoperatively, SjO(2) was determined by intermittent blood sampling, and postoperatively, the area under the curve of SjO(2) < 50% and time was calculated from continuous reflectance oximetry. No significant correlations between cognitive performance and either intra- or postoperative SjO(2) were found. Preoperative cognitive performance was the main determinant of cognition at 3 mo (r(2) = 0.83, P<0.001), and palpable atheroma of the ascending aorta made a small, but significant, contribution to a decline in cognition (r(2) = 0.018, P = 0.001).

Continuous monitoring of jugular bulb oxyhaemoglobin saturation using the Edslab dual lumen oximetry catheter during and after cardiac surgery.

Fibreoptic jugular bulb oximetry has been validated for use in the care of severely head-injured patients. We compared bench and fibreoptic methods of measuring jugular bulb oxyhaemoglobin saturation (SjO2) in 33 patients undergoing cardiac surgery both during cardiopulmonary bypass (CPB) and in the early postoperative period. After insertion of a fibreoptic reflectance oximetry catheter into the jugular bulb, it was calibrated against a bench oximeter. Comparisons were made while on CPB (n = 60) and in the postoperative period for up to 18 h (n = 215). There was negligible bias throughout. There were wide limits of agreements (mean difference +/- 2SD) between the two methods during operation (-20.29% to 18.05%), whereas after operation the limits of agreement were far narrower (-6.39% and 7.45%). Measurement of SjO2 by the fibreoptic method compared poorly with bench oximetry during CPB but there was good agreement between the two methods in the early postoperative period.

Aerobic, anaerobic and combination estimates of cerebral hypoperfusion during and after cardiac surgery.

We studied 15 patients undergoing cardiac surgery involving hypothermic cardiopulmonary bypass (CPB). Cerebral arteriovenous difference in oxygen content (AVDO2) was significantly less during CPB and for up to 18 h after operation compared with pre-CPB values (P < 0.05). There were no significant changes in mean jugular bulb oxyhaemoglobin saturation (SjvO2), cerebral arteriovenous difference in lactate content or lactate-oxygen index (LOI). SjVO2 and arterial carbon dioxide tension (PaCO2) (P = 0.005) were positively correlated as were AVDO2 and haemoglobin concentration (P = 0.012). AVDO2 and PaCO2 (P = 0.007) were negatively correlated as were LOI and arterial oxyhaemoglobin saturation (P = 0.037). There were no significant correlations between mean arterial pressure and any of the variables. SjVO2 and AVDO2 may require correction for changes in PaCO2 and haemoglobin concentration before relating these variables to cerebral outcome.

Jugular venous desaturation following cardiac surgery.

Twenty-two patients undergoing coronary artery bypass surgery underwent postoperative measurement and recording of jugular venous oxyhaemoglobin saturation (SjO2) with desaturation defined as a value of less than 50% for 5 min or longer. Fifteen of the 22 patients monitored experienced desaturations. An average of four episodes were experienced by those 15 patients (range 1-14). The mean duration of a single episode was 46 (range 5-212) min whilst mean total duration of desaturation was 175 (range 5-570) min. The mean duration of desaturation in the 15 patients, expressed as a percentage of monitored time, was 21.1% (range 0.58%-61.96%). SjO2 desaturation, possibly indicating cerebral hypoperfusion, occurs in the early post-operative period following cardiac surgery.